Asymptomatic Plasmodium Infections in Children in Low Malaria Transmission Setting, Southwestern Uganda(1).

PubMed

Roh, Michelle E; Oyet, Caesar; Orikiriza, Patrick; Wade, Martina; Kiwanuka, Gertrude N; Mwanga-Amumpaire, Juliet; Parikh, Sunil; Boum, Yap

2016-08-01

A survey of asymptomatic children in Uganda showed Plasmodium malariae and P. falciparum parasites in 45% and 55% of microscopy-positive samples, respectively. Although 36% of microscopy-positive samples were negative by rapid diagnostic test, 75% showed P. malariae or P. ovale parasites by PCR, indicating that routine diagnostic testing misses many non-P. falciparum malarial infections.

Evaluation of 9 rapid diagnostic tests for screening HIV infection, in Lomé, Togo.

PubMed

Dagnra, A Y; Dossim, S; Salou, M; Nyasenu, T; Ali-Edje, K; Ouro-Médeli, A; Doufan, M; Ehlan, A; Prince-David, M

2014-12-01

HIV rapid diagnostic tests (RDT) could be greatly contributive for a universal access to HIV diagnosis. However, according to the WHO, these tests need to be assessed before they can be used in routine. We assessed 9 RDT in routine clinical use between 2009 and 2013. The sensitivity and specificity observed for 7 tests were≥99% and≥98%, respectively: FIRST RESPONSE HIV1-2-O PMC Medical, India, GENIE Fast HIV 1-2 and GENIE™ III HIV(1/2) Bio-Rad, France, HIV TRI-DOT+Ag;J. Mitra, INDIA; SD BIOLINE HIV(1/2) 3.0 and SD BIOLINE HIV/SYPHILIS DUO Standard Diagnostic, Korea; and VIKIA HIV(1/2); BioMérieux, France. Two tests had performances inferior to WHO recommendations: INSTI HIV1/2 Biolytical Canada; sensitivity=97.8% and HEXAGON HIV HUMAN GmbH Germany; specificity=94.8%. Seven of 9 RDT had excellent performances. Nevertheless, they can be used only after training staff, and taking into account national algorithm for their safe use. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Summary of Part 75 Administrative Processes: Table 1

EPA Pesticide Factsheets

Learn how to submit your initial certification, recertification, monitoring plans, routine quality assurance tests, diagnostic tests and DAHS verifications, low mass emissions units and other notification requirements. Table 1, initial certification.

Diagnostic triage and the role of natriuretic peptide testing and echocardiography for suspected heart failure: an appropriateness ratings evaluation by UK GPs

PubMed Central

Campbell, Stephen M; Fuat, Ahmet; Summerton, Nick; Lancaster, Neil; Hobbs, FD Richard

2011-01-01

Background Some UK GPs are acquiring access to natriuretic peptide (NP) testing or echocardiography as diagnostic tests for heart failure. This study developed appropriateness ratings for the diagnostic application of these tests in routine general practice. Aim To develop appropriateness ratings for the diagnostic application of NP testing or echocardiography for heart failure in general practice. Design and setting An appropriateness ratings evaluation in UK general practice. Method Four presenting symptoms (cough, bilateral ankle swelling, dyspnoea, fatigue), three levels of risk of cardiovascular disease (low, intermediate, high), and dichotomous categorisations of cardiovascular/chest examination and electrocardiogram result, were used to create 540 appropriateness scenarios for patients in whom NP testing or echocardiography might be considered. These were rated by a 10-person expert panel, consisting of GPs and GPs with specialist interests in cardiology, in a two-round RAND Appropriateness Method. Results Onward referral for NP testing or echocardiography was rated as an appropriate next step in 217 (40.2%) of the 540 scenarios; in 194 (35.9%) it was rated inappropriate. The ratings also show where NP testing or echocardiography were ranked as equivalent next steps and when one test was seen as the more appropriate than the other. Conclusion NP testing should be the routine test for suspected heart failure where referral for diagnostic testing is considered appropriate. An abnormal electrocardiogram status makes referral to echocardiography an accompanying, or more appropriate, next step alongside NP testing, especially in the presence of dyspnoea. Abnormal NP testing should subsequently be followed up with referral for echocardiography. PMID:21722451

The potential of high resolution melting analysis (hrma) to streamline, facilitate and enrich routine diagnostics in medical microbiology.

PubMed

Ruskova, Lenka; Raclavsky, Vladislav

2011-09-01

Routine medical microbiology diagnostics relies on conventional cultivation followed by phenotypic techniques for identification of pathogenic bacteria and fungi. This is not only due to tradition and economy but also because it provides pure culture needed for antibiotic susceptibility testing. This review focuses on the potential of High Resolution Melting Analysis (HRMA) of double-stranded DNA for future routine medical microbiology. Search of MEDLINE database for publications showing the advantages of HRMA in routine medical microbiology for identification, strain typing and further characterization of pathogenic bacteria and fungi in particular. The results show increasing numbers of newly-developed and more tailor-made assays in this field. For microbiologists unfamiliar with technical aspects of HRMA, we also provide insight into the technique from the perspective of microbial characterization. We can anticipate that the routine availability of HRMA in medical microbiology laboratories will provide a strong stimulus to this field. This is already envisioned by the growing number of medical microbiology applications published recently. The speed, power, convenience and cost effectiveness of this technology virtually predestine that it will advance genetic characterization of microbes and streamline, facilitate and enrich diagnostics in routine medical microbiology without interfering with the proven advantages of conventional cultivation.

Practical issues in implementing whole-genome-sequencing in routine diagnostic microbiology.

PubMed

Rossen, J W A; Friedrich, A W; Moran-Gilad, J

2018-04-01

Next generation sequencing (NGS) is increasingly being used in clinical microbiology. Like every new technology adopted in microbiology, the integration of NGS into clinical and routine workflows must be carefully managed. To review the practical aspects of implementing bacterial whole genome sequencing (WGS) in routine diagnostic laboratories. Review of the literature and expert opinion. In this review, we discuss when and how to integrate whole genome sequencing (WGS) in the routine workflow of the clinical laboratory. In addition, as the microbiology laboratories have to adhere to various national and international regulations and criteria for their accreditation, we deliberate on quality control issues for using WGS in microbiology, including the importance of proficiency testing. Furthermore, the current and future place of this technology in the diagnostic hierarchy of microbiology is described as well as the necessity of maintaining backwards compatibility with already established methods. Finally, we speculate on the question of whether WGS can entirely replace routine microbiology in the future and the tension between the fact that most sequencers are designed to process multiple samples in parallel whereas for optimal diagnosis a one-by-one processing of the samples is preferred. Special reference is made to the cost and turnaround time of WGS in diagnostic laboratories. Further development is required to improve the workflow for WGS, in particular to shorten the turnaround time, reduce costs, and streamline downstream data analyses. Only when these processes reach maturity will reliance on WGS for routine patient management and infection control management become feasible, enabling the transformation of clinical microbiology into a genome-based and personalized diagnostic field. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

A clinical perspective on the 2016 WHO brain tumor classification and routine molecular diagnostics.

PubMed

van den Bent, Martin J; Weller, Michael; Wen, Patrick Y; Kros, Johan M; Aldape, Ken; Chang, Susan

2017-05-01

The 2007 World Health Organization (WHO) classification of brain tumors did not use molecular abnormalities as diagnostic criteria. Studies have shown that genotyping allows a better prognostic classification of diffuse glioma with improved treatment selection. This has resulted in a major revision of the WHO classification, which is now for adult diffuse glioma centered around isocitrate dehydrogenase (IDH) and 1p/19q diagnostics. This revised classification is reviewed with a focus on adult brain tumors, and includes a recommendation of genes of which routine testing is clinically useful. Apart from assessment of IDH mutational status including sequencing of R132H-immunohistochemistry negative cases and testing for 1p/19q, several other markers can be considered for routine testing, including assessment of copy number alterations of chromosome 7 and 10 and of TERT promoter, BRAF, and H3F3A mutations. For "glioblastoma, IDH mutated" the term "astrocytoma grade IV" could be considered. It should be considered to treat IDH wild-type grades II and III diffuse glioma with polysomy of chromosome 7 and loss of 10q as glioblastoma. New developments must be more quickly translated into further revised diagnostic categories. Quality control and rapid integration of molecular findings into the final diagnosis and the communication of the final diagnosis to clinicians require systematic attention. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Challenges in Routine Implementation and Quality Control of Rapid Diagnostic Tests for Malaria–Rufiji District, Tanzania

PubMed Central

McMorrow, Meredith L.; Masanja, M. Irene; Abdulla, Salim M. K.; Kahigwa, Elizeus; Kachur, S. Patrick

2018-01-01

Rapid diagnostic tests (RDTs) represent an alternative to microscopy for malaria diagnosis and have shown high sensitivity and specificity in a variety of study settings. Current World Health Organization (WHO) guidelines for quality control of RDTs provide detailed instructions on pre-field testing, but offer little guidance for quality assurance once RDTs are deployed in health facilities. From September 2006 to April 2007, we introduced a histidine-rich protein II (HRP2)-based RDT (Paracheck) for suspected malaria cases five years of age and older in nine health facilities in Rufiji District, Tanzania, to assess sensitivity and specificity of RDTs in routine use at rural health facilities. Thick blood smears were collected for all patients tested with RDTs and stained and read by laboratory personnel in each facility. Thick smears were subsequently reviewed by a reference microscopist to determine RDT sensitivity and specificity. In all nine health facilities, there were significant problems with the quality of staining and microscopy. Sensitivity and specificity of RDTs were difficult to assess given the poor quality of routine blood smear staining. Mean operational sensitivity of RDTs based on reference microscopy was 64.8%, but varied greatly by health facility, range 18.8–85.9%. Sensitivity of RDTs increased with increasing parasite density. Specificity remained high at 87.8% despite relatively poor slide quality. Institution of quality control of RDTs based on poor quality blood smear staining may impede reliable measurement of sensitivity and specificity and undermine confidence in the new diagnostic. There is an urgent need for the development of alternative quality control procedures for rapid diagnostic tests that can be performed at the facility level. PMID:18784230

Parallel recovery in a trilingual speaker: the use of the Bilingual Aphasia Test as a diagnostic complement to the Comprehensive Aphasia Test

PubMed Central

GREEN, DAVID W.; RUFFLE, LOUISE; GROGAN, ALICE; ALI, NILUFA; RAMSDEN, SUE; SCHOFIELD, TOM; LEFF, ALEX P.; CRINION, JENNY; PRICE, CATHY J.

2011-01-01

We illustrate the value of the Bilingual Aphasia Test in the diagnostic assessment of a trilingual speaker post-stroke living in England for whom English was a non-native language. The Comprehensive Aphasia Test is routinely used to assess patients in English but only in combination with the Bilingual Aphasia Test is it possible and practical to provide a fuller picture of the language impairment. We describe our test selection and the assessment it allows us to make. PMID:21453044

Simpler score of routine laboratory tests predicts liver fibrosis in patients with chronic hepatitis B.

PubMed

Zhou, Kun; Gao, Chun-Fang; Zhao, Yun-Peng; Liu, Hai-Lin; Zheng, Rui-Dan; Xian, Jian-Chun; Xu, Hong-Tao; Mao, Yi-Min; Zeng, Min-De; Lu, Lun-Gen

2010-09-01

In recent years, a great interest has been dedicated to the development of noninvasive predictive models to substitute liver biopsy for fibrosis assessment and follow-up. Our aim was to provide a simpler model consisting of routine laboratory markers for predicting liver fibrosis in patients chronically infected with hepatitis B virus (HBV) in order to optimize their clinical management. Liver fibrosis was staged in 386 chronic HBV carriers who underwent liver biopsy and routine laboratory testing. Correlations between routine laboratory markers and fibrosis stage were statistically assessed. After logistic regression analysis, a novel predictive model was constructed. This S index was validated in an independent cohort of 146 chronic HBV carriers in comparison to the SLFG model, Fibrometer, Hepascore, Hui model, Forns score and APRI using receiver operating characteristic (ROC) curves. The diagnostic values of each marker panels were better than single routine laboratory markers. The S index consisting of gamma-glutamyltransferase (GGT), platelets (PLT) and albumin (ALB) (S-index: 1000 x GGT/(PLT x ALB(2))) had a higher diagnostic accuracy in predicting degree of fibrosis than any other mathematical model tested. The areas under the ROC curves (AUROC) were 0.812 and 0.890 for predicting significant fibrosis and cirrhosis in the validation cohort, respectively. The S index, a simpler mathematical model consisting of routine laboratory markers predicts significant fibrosis and cirrhosis in patients with chronic HBV infection with a high degree of accuracy, potentially decreasing the need for liver biopsy.

Molecular allergy diagnostics using multiplex assays: methodological and practical considerations for use in research and clinical routine: Part 21 of the Series Molecular Allergology.

PubMed

Jakob, Thilo; Forstenlechner, Peter; Matricardi, Paolo; Kleine-Tebbe, Jörg

The availability of single allergens and their use in microarray technology enables the simultaneous determination of specific IgE (sIgE) to a multitude of different allergens (> 100) in a multiplex procedure requiring only minute amounts of serum. This allows extensive individual sensitization profiles to be determined from a single analysis. Combined with a patient's medical history, these profiles simplify identification of cross-reactivity; permit a more accurate estimation of the risk of severe reactions; and enable the indication for specific immunotherapy to be more precisely established, particularly in cases of polysensitization. Strictly speaking, a multiplex assay is not a single test, but instead more than 100 simultaneous tests. This places considerable demands on the production, quality assurance, and interpretation of data. The following chapter describes the multiplex test systems currently available and discusses their characteristics. Performance data are presented and the sIgE values obtained from multiplex and singleplex assays are compared. Finally, the advantages and limitations of molecular allergy diagnostics using multiplex assays in clinical routine are discussed, and innovative possibilities for clinical research are described. The multiplex diagnostic tests available for clinical routine have now become well established. The interpretation of test results is demanding, particularly since all individual results need to be checked for their plausibility and clinical relevance on the basis of previous history (patient history, clinical symptoms, challenge test results). There is still room for improvement in certain areas, for example with respect to the overall test sensitivity of the method, as well as the availability and quality of particular allergens. The current test systems are just the beginning of a continuous development that will influence and most likely change clinical allergology in the coming years.

Rapid extraction of virus-contaminated hemocytes from oysters

USDA-ARS?s Scientific Manuscript database

Rapid viral detection methods are necessary to employ diagnostic testing for viral contamination in shellfish to prevent and control foodborne illness. Current shellfish viral RNA extraction methods, which are time-consuming and not applicable for routine monitoring, require the testing of whole or ...

Nucleic acid-based diagnostics for infectious diseases in public health affairs.

PubMed

Yu, Albert Cheung-Hoi; Vatcher, Greg; Yue, Xin; Dong, Yan; Li, Mao Hua; Tam, Patrick H K; Tsang, Parker Y L; Wong, April K Y; Hui, Michael H K; Yang, Bin; Tang, Hao; Lau, Lok-Ting

2012-06-01

Infectious diseases, mostly caused by bacteria and viruses but also a result of fungal and parasitic infection, have been one of the most important public health concerns throughout human history. The first step in combating these pathogens is to get a timely and accurate diagnosis at an affordable cost. Many kinds of diagnostics have been developed, such as pathogen culture, biochemical tests and serological tests, to help detect and fight against the causative agents of diseases. However, these diagnostic tests are generally unsatisfactory because they are not particularly sensitive and specific and are unable to deliver speedy results. Nucleic acid-based diagnostics, detecting pathogens through the identification of their genomic sequences, have shown promise to overcome the above limitations and become more widely adopted in clinical tests. Here we review some of the most popular nucleic acid-based diagnostics and focus on their adaptability and applicability to routine clinical usage. We also compare and contrast the characteristics of different types of nucleic acid-based diagnostics.

Diagnostic accuracy of routine blood examinations and CSF lactate level for post-neurosurgical bacterial meningitis.

PubMed

Zhang, Yang; Xiao, Xiong; Zhang, Junting; Gao, Zhixian; Ji, Nan; Zhang, Liwei

2017-06-01

To evaluate the diagnostic accuracy of routine blood examinations and Cerebrospinal Fluid (CSF) lactate level for Post-neurosurgical Bacterial Meningitis (PBM) at a large sample-size of post-neurosurgical patients. The diagnostic accuracies of routine blood examinations and CSF lactate level to distinguish between PAM and PBM were evaluated with the values of the Area Under the Curve of the Receiver Operating Characteristic (AUC -ROC ) by retrospectively analyzing the datasets of post-neurosurgical patients in the clinical information databases. The diagnostic accuracy of routine blood examinations was relatively low (AUC -ROC <0.7). The CSF lactate level achieved rather high diagnostic accuracy (AUC -ROC =0.891; CI 95%, 0.852-0.922). The variables of patient age, operation duration, surgical diagnosis and postoperative days (the interval days between the neurosurgery and examinations) were shown to affect the diagnostic accuracy of these examinations. The variables were integrated with routine blood examinations and CSF lactate level by Fisher discriminant analysis to improve their diagnostic accuracy. As a result, the diagnostic accuracy of blood examinations and CSF lactate level was significantly improved with an AUC -ROC value=0.760 (CI 95%, 0.737-0.782) and 0.921 (CI 95%, 0.887-0.948) respectively. The PBM diagnostic accuracy of routine blood examinations was relatively low, whereas the accuracy of CSF lactate level was high. Some variables that are involved in the incidence of PBM can also affect the diagnostic accuracy for PBM. Taking into account the effects of these variables significantly improves the diagnostic accuracies of routine blood examinations and CSF lactate level. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

New diagnostics for latent and active tuberculosis: state of the art and future prospects.

PubMed

Pai, Madhukar; O'Brien, Richard

2008-10-01

Tuberculosis (TB) continues to be the world's most important infectious cause of morbidity and mortality among adults. Nearly 9 million people develop TB disease each year, and an estimated 1.6 million die from the disease. Despite this enormous global burden, case detection rates are low, posing serious hurdles for TB control. Conventional TB diagnosis continues to rely on antiquated tests such as sputum smear microscopy, culture, tuberculin skin test, and chest radiography. These tests have several limitations and perform poorly in populations affected by the HIV epidemic. Conventional tests for detection of drug resistance are time consuming, tedious, and inaccessible in most settings. In this review, we describe recent advances in the diagnosis of latent and active TB, and detection of drug resistance. Although the perfect test will not be ready for large-scale roll-out and integration into routine TB care services for some time, substantial progress has been made in expanding the TB diagnostic product pipeline. With the resurgence of interest in the development of new tools for TB control, and the recent influx of funding and political support, it is likely that the next few years will see the introduction of new diagnostic tools into routine TB control programs.

Comparison of Biotinylated Monoclonal and Polyclonal Antibodies in an Evaluation of a Direct Rapid Immunohistochemical Test for the Routine Diagnosis of Rabies in Southern Africa

PubMed Central

Coetzer, Andre; Sabeta, Claude T.; Markotter, Wanda; Rupprecht, Charles E.; Nel, Louis H.

2014-01-01

The major etiological agent of rabies, rabies virus (RABV), accounts for tens of thousands of human deaths per annum. The majority of these deaths are associated with rabies cycles in dogs in resource-limited countries of Africa and Asia. Although routine rabies diagnosis plays an integral role in disease surveillance and management, the application of the currently recommended direct fluorescent antibody (DFA) test in countries on the African and Asian continents remains quite limited. A novel diagnostic assay, the direct rapid immunohistochemical test (dRIT), has been reported to have a diagnostic sensitivity and specificity equal to that of the DFA test while offering advantages in cost, time and interpretation. Prior studies used the dRIT utilized monoclonal antibody (MAb) cocktails. The objective of this study was to test the hypothesis that a biotinylated polyclonal antibody (PAb) preparation, applied in the dRIT protocol, would yield equal or improved results compared to the use of dRIT with MAbs. We also wanted to compare the PAb dRIT with the DFA test, utilizing the same PAb preparation with a fluorescent label. The PAb dRIT had a diagnostic sensitivity and specificity of 100%, which was shown to be marginally higher than the diagnostic efficacy observed for the PAb DFA test. The classical dRIT, relying on two-biotinylated MAbs, was applied to the same panel of samples and a reduced diagnostic sensitivity (83.50% and 90.78% respectively) was observed. Antigenic typing of the false negative samples indicated all of these to be mongoose RABV variants. Our results provided evidence that a dRIT with alternative antibody preparations, conjugated to a biotin moiety, has a diagnostic efficacy equal to that of a DFA relying on the same antibody and that the antibody preparation should be optimized for virus variants specific to the geographical area of focus. PMID:25254652

Comparison of biotinylated monoclonal and polyclonal antibodies in an evaluation of a direct rapid immunohistochemical test for the routine diagnosis of rabies in southern Africa.

PubMed

Coetzer, Andre; Sabeta, Claude T; Markotter, Wanda; Rupprecht, Charles E; Nel, Louis H

2014-09-01

The major etiological agent of rabies, rabies virus (RABV), accounts for tens of thousands of human deaths per annum. The majority of these deaths are associated with rabies cycles in dogs in resource-limited countries of Africa and Asia. Although routine rabies diagnosis plays an integral role in disease surveillance and management, the application of the currently recommended direct fluorescent antibody (DFA) test in countries on the African and Asian continents remains quite limited. A novel diagnostic assay, the direct rapid immunohistochemical test (dRIT), has been reported to have a diagnostic sensitivity and specificity equal to that of the DFA test while offering advantages in cost, time and interpretation. Prior studies used the dRIT utilized monoclonal antibody (MAb) cocktails. The objective of this study was to test the hypothesis that a biotinylated polyclonal antibody (PAb) preparation, applied in the dRIT protocol, would yield equal or improved results compared to the use of dRIT with MAbs. We also wanted to compare the PAb dRIT with the DFA test, utilizing the same PAb preparation with a fluorescent label. The PAb dRIT had a diagnostic sensitivity and specificity of 100%, which was shown to be marginally higher than the diagnostic efficacy observed for the PAb DFA test. The classical dRIT, relying on two-biotinylated MAbs, was applied to the same panel of samples and a reduced diagnostic sensitivity (83.50% and 90.78% respectively) was observed. Antigenic typing of the false negative samples indicated all of these to be mongoose RABV variants. Our results provided evidence that a dRIT with alternative antibody preparations, conjugated to a biotin moiety, has a diagnostic efficacy equal to that of a DFA relying on the same antibody and that the antibody preparation should be optimized for virus variants specific to the geographical area of focus.

Heavy Metal Pad Shielding during Fluoroscopic Interventions

PubMed Central

Dromi, Sergio; Wood, Bradford J.; Oberoi, Jay; Neeman, Ziv

2008-01-01

Significant direct and scatter radiation doses to patient and physician may result from routine interventional radiology practice. A lead-free disposable tungsten antimony shielding pad was tested in phantom patients during simulated diagnostic angiography procedures. Although the exact risk of low doses of ionizing radiation is unknown, dramatic dose reductions can be seen with routine use of this simple, sterile pad made from lightweighttungsten antimony material. PMID:16868175

Impact of target organ damage assessment in the evaluation of global risk in patients with essential hypertension.

PubMed

Viazzi, Francesca; Leoncini, Giovanna; Parodi, Denise; Ratto, Elena; Vettoretti, Simone; Vaccaro, Valentina; Parodi, Angelica; Falqui, Valeria; Tomolillo, Cinzia; Deferrari, Giacomo; Pontremoli, Roberto

2005-03-01

Accurate assessment of cardiovascular risk is a key step toward optimizing the treatment of hypertensive patients. We analyzed the impact and cost-effectiveness of routine, thorough assessment of target organ damage (TOD) in evaluating risk profile in hypertension. A total of 380 never-treated patients with essential hypertension underwent routine work-up plus evaluation of albuminuria and ultrasonography of cardiac and vascular structures. The impact of these tests on risk stratification, as indicated by European Society of Hypertension-European Society of Cardiology guidelines, was assessed in light of their cost and sensitivity. The combined use of all of these tests greatly improved the detection of TOD, therefore leading to the identification of a higher percentage of patients who were at high/very high risk, as compared with those who were detected by routine clinical work-up (73% instead of 42%; P < 0.0001). Different signs of TOD only partly cluster within the same subgroup of patients; thus, all three tests should be performed to maximize the sensitivity of the evaluation process. The diagnostic algorithm yielding the lowest cost per detected case of TOD is the search for microalbuminuria, followed by echocardiography and then carotid ultrasonography. Adopting lower cut-off values to define microalbuminuria allows us to optimize further the cost-effectiveness of diagnostic algorithms. In conclusion, because of its low cost and widespread availability, measuring albuminuria is an attractive and cost-effective screening test that is especially suitable as the first step in the large-scale diagnostic work-up of hypertensive patients.

NGS of Virus-Derived Small RNAs as a Diagnostic Method Used to Determine Viromes of Hungarian Vineyards

PubMed Central

Czotter, Nikoletta; Molnar, Janos; Szabó, Emese; Demian, Emese; Kontra, Levente; Baksa, Ivett; Szittya, Gyorgy; Kocsis, Laszlo; Deak, Tamas; Bisztray, Gyorgy; Tusnady, Gabor E.; Burgyan, Jozsef; Varallyay, Eva

2018-01-01

As virus diseases cannot be controlled by traditional plant protection methods, the risk of their spread have to be minimized on vegetatively propagated plants, such as grapevine. Metagenomic approaches used for virus diagnostics offer a unique opportunity to reveal the presence of all viral pathogens in the investigated plant, which is why their application can reduce the risk of using infected material for a new plantation. Here we used a special branch, deep sequencing of virus-derived small RNAs, of this high-throughput method for virus diagnostics, and determined viromes of vineyards in Hungary. With NGS of virus-derived small RNAs we could detect not only the viruses tested routinely, but also new ones, which had never been described in Hungary before. Virus presence did not correlate with the age of the plantation, moreover phylogenetic analysis of the identified virus isolates suggests that infections are mostly caused by the use of infected propagating material. Our results, validated by other molecular methods, raised further questions to be answered before this method can be introduced as a routine, reliable test for grapevine virus diagnostics. PMID:25741336

Diagnostic accuracy of two multiplex real-time polymerase chain reaction assays for the diagnosis of meningitis in children in a resource-limited setting.

PubMed

Khumalo, Jermaine; Nicol, Mark; Hardie, Diana; Muloiwa, Rudzani; Mteshana, Phindile; Bamford, Colleen

2017-01-01

Accurate etiological diagnosis of meningitis is important, but difficult in resource-limited settings due to prior administration of antibiotics and lack of viral diagnostics. We aimed to develop and validate 2 real-time multiplex PCR (RT-PCR) assays for the detection of common causes of community-acquired bacterial and viral meningitis in South African children. We developed 2 multiplex RT- PCRs for detection of S. pneumoniae, N. meningitidis, H. influenzae, enteroviruses, mumps virus and herpes simplex virus. We tested residual CSF samples from children presenting to a local paediatric hospital over a one-year period, whose CSF showed an abnormal cell count. Results were compared with routine diagnostic tests and the final discharge diagnosis. We calculated accuracy of the bacterial RT-PCR assay compared to CSF culture and using World Health Organisation definitions of laboratory-confirmed bacterial meningitis. From 292 samples, bacterial DNA was detected in 12 (4.1%) and viral nucleic acids in 94 (32%). Compared to CSF culture, the sensitivity and specificity of the bacterial RT-PCR was 100% and 97.2% with complete agreement in organism identification. None of the cases positive by viral RT-PCR had a bacterial cause confirmed on CSF culture. Only 9/90 (10%) of patients diagnosed clinically as bacterial meningitis or partially treated bacterial meningitis tested positive with the bacterial RT-PCR. In this population the use of 2 multiplex RT-PCRs targeting 6 common pathogens gave promising results. If introduced into routine diagnostic testing, these multiplex RT-PCR assays would supplement other diagnostic tests, and have the potential to limit unnecessary antibiotic therapy and hospitalisation.

Diagnostic accuracy of two multiplex real-time polymerase chain reaction assays for the diagnosis of meningitis in children in a resource-limited setting

PubMed Central

Khumalo, Jermaine; Nicol, Mark; Hardie, Diana; Muloiwa, Rudzani; Mteshana, Phindile

2017-01-01

Introduction Accurate etiological diagnosis of meningitis is important, but difficult in resource-limited settings due to prior administration of antibiotics and lack of viral diagnostics. We aimed to develop and validate 2 real-time multiplex PCR (RT-PCR) assays for the detection of common causes of community-acquired bacterial and viral meningitis in South African children. Methods We developed 2 multiplex RT- PCRs for detection of S. pneumoniae, N. meningitidis, H. influenzae, enteroviruses, mumps virus and herpes simplex virus. We tested residual CSF samples from children presenting to a local paediatric hospital over a one-year period, whose CSF showed an abnormal cell count. Results were compared with routine diagnostic tests and the final discharge diagnosis. We calculated accuracy of the bacterial RT-PCR assay compared to CSF culture and using World Health Organisation definitions of laboratory-confirmed bacterial meningitis. Results From 292 samples, bacterial DNA was detected in 12 (4.1%) and viral nucleic acids in 94 (32%). Compared to CSF culture, the sensitivity and specificity of the bacterial RT-PCR was 100% and 97.2% with complete agreement in organism identification. None of the cases positive by viral RT-PCR had a bacterial cause confirmed on CSF culture. Only 9/90 (10%) of patients diagnosed clinically as bacterial meningitis or partially treated bacterial meningitis tested positive with the bacterial RT-PCR. Discussion In this population the use of 2 multiplex RT-PCRs targeting 6 common pathogens gave promising results. If introduced into routine diagnostic testing, these multiplex RT-PCR assays would supplement other diagnostic tests, and have the potential to limit unnecessary antibiotic therapy and hospitalisation. PMID:28346504

Routine opt-out rapid HIV screening and detection of HIV infection in emergency department patients.

PubMed

Haukoos, Jason S; Hopkins, Emily; Conroy, Amy A; Silverman, Morgan; Byyny, Richard L; Eisert, Sheri; Thrun, Mark W; Wilson, Michael L; Hutchinson, Angela B; Forsyth, Jessica; Johnson, Steven C; Heffelfinger, James D

2010-07-21

The Centers for Disease Control and Prevention (CDC) recommends routine (nontargeted) opt-out HIV screening in health care settings, including emergency departments (EDs), where the prevalence of undiagnosed infection is 0.1% or greater. The utility of this approach in EDs remains unknown. To determine whether nontargeted opt-out rapid HIV screening in the ED was associated with identification of more patients with newly diagnosed HIV infection than physician-directed diagnostic rapid HIV testing. Quasi-experimental equivalent time-samples design in an urban public safety-net hospital with an approximate annual ED census of 55,000 patient visits. Patients were 16 years or older and capable of providing consent for rapid HIV testing. Nontargeted opt-out rapid HIV screening and physician-directed diagnostic rapid HIV testing alternated in sequential 4-month time intervals between April 15, 2007, and April 15, 2009. Number of patients with newly identified HIV infection and the association between nontargeted opt-out rapid HIV screening and identification of HIV infection. In the opt-out phase, of 28,043 eligible ED patients, 6933 patients (25%) completed HIV testing (6702 patients were screened; 231 patients were diagnostically tested). Ten of 6702 patients (0.15%; 95% CI, 0.07%-0.27%) who did not decline HIV screening in the opt-out phase had new HIV diagnoses, and 5 of 231 patients (2.2%; 95% CI, 0.7%-5.0%) who were diagnostically tested during the opt-out phase had new HIV diagnoses. In the diagnostic phase, of 29,925 eligible patients, 243 (0.8%) completed HIV testing. Of these, 4 patients (1.6%; 95% CI, 0.5%-4.2%) had new diagnoses. The prevalence of new HIV diagnoses in the opt-out phase (including those diagnostically tested) and in the diagnostic phase was 15 in 28,043 (0.05%; 95% CI, 0.03%-0.09%) and 4 in 29,925 (0.01%; 95% CI, 0.004%-0.03%), respectively. Nontargeted opt-out HIV screening was independently associated with new HIV diagnoses (risk ratio, 3.6; 95% CI, 1.2-10.8) when adjusting for patient demographics, insurance status, and whether diagnostic testing was performed in the opt-out phase. The median CD4 cell count for those with new HIV diagnoses in the opt-out phase (including those diagnostically tested) and in the diagnostic phase was 69/microL (IQR, 17-430) and 13/microL (IQR, 11-15) , respectively (P = .02). Nontargeted opt-out rapid HIV screening in the ED, vs diagnostic testing, was associated with identification of a modestly increased number of patients with new HIV diagnoses, most of whom were identified late in the course of disease.

Survey of six rose viruses in a rose virus collection

USDA-ARS?s Scientific Manuscript database

More than 25 viruses have been reported to infect roses. As part of the routine diagnostic testing at Foundation Plant Services, roses are tested for viruses by biological, serological, and molecular assays. Over the past 18 years, we identified approximately 600 roses that were worth maintaining as...

Comparing Phytophthora ramorum diagnostic protocols for the national Sudden Oak death stream monitoring program

Treesearch

W. Sutton; E.M. Hansen; P. Reeser; A. Kanaskie

2008-01-01

Oregon was a participant in the pilot test of the national stream monitoring protocol for SOD. We routinely and continuously monitor about 50 streams in and near the SOD quarantine area in southwest Oregon using foliage baits. For the national protocol, we added six additional streams beyond the area of known infestation, and compared results from different diagnostic...

Evaluation of Targeted Next-Generation Sequencing for Detection of Bovine Pathogens in Clinical Samples.

PubMed

Anis, Eman; Hawkins, Ian K; Ilha, Marcia R S; Woldemeskel, Moges W; Saliki, Jeremiah T; Wilkes, Rebecca P

2018-07-01

The laboratory diagnosis of infectious diseases, especially those caused by mixed infections, is challenging. Routinely, it requires submission of multiple samples to separate laboratories. Advances in next-generation sequencing (NGS) have provided the opportunity for development of a comprehensive method to identify infectious agents. This study describes the use of target-specific primers for PCR-mediated amplification with the NGS technology in which pathogen genomic regions of interest are enriched and selectively sequenced from clinical samples. In the study, 198 primers were designed to target 43 common bovine and small-ruminant bacterial, fungal, viral, and parasitic pathogens, and a bioinformatics tool was specifically constructed for the detection of targeted pathogens. The primers were confirmed to detect the intended pathogens by testing reference strains and isolates. The method was then validated using 60 clinical samples (including tissues, feces, and milk) that were also tested with other routine diagnostic techniques. The detection limits of the targeted NGS method were evaluated using 10 representative pathogens that were also tested by quantitative PCR (qPCR), and the NGS method was able to detect the organisms from samples with qPCR threshold cycle ( C T ) values in the 30s. The method was successful for the detection of multiple pathogens in the clinical samples, including some additional pathogens missed by the routine techniques because the specific tests needed for the particular organisms were not performed. The results demonstrate the feasibility of the approach and indicate that it is possible to incorporate NGS as a diagnostic tool in a cost-effective manner into a veterinary diagnostic laboratory. Copyright © 2018 Anis et al.

Performance of two strategies for urgent ANCA and anti-GBM analysis in vasculitis.

PubMed

de Joode, Anoek A E; Roozendaal, Caroline; van der Leij, Marcel J; Bungener, Laura B; Sanders, Jan Stephan F; Stegeman, Coen A

2014-02-01

In anti-neutrophil cytoplasmic antibodies (ANCA) associated small vessel vasculitis (AAV), rapid testing for ANCA and anti-glomerular basement membrane (GBM) antibodies may be beneficial for therapeutic purpose. We analysed the diagnostic performance of two rapid ANCA and anti-GBM test methods in 260 patients with suspected AAV. Between January 2004 and November 2010, we analysed 260 samples by qualitative Dotblot (Biomedical Diagnostics); retrospective analysis followed with directly coated highly sensitive automated Phadia ELiA and ELiA anti-GBM. Results were related to the final clinical diagnosis and compared with routine capture ELISA. Seventy-four patients had a final diagnosis of AAV (n=62) or anti-GBM disease (n=12). Both Dotblot and ELiA detected all 12 cases of anti-GBM disease; 2 false positive results were found. Dotblot detected ANCA in 56 of 62 AAV patients (sensitivity 90%, NPV 97%), and showed 5 false positives (specificity 97%, PPV 90%). The Phadia ELiA anti-PR3(s) or anti-MPO(s) was positive in 57 of 62 AAV patients (sensitivity 92%, NPV 97%), and had 5 false positives (specificity 97%, PPV 88%). Routine capture ELISA was equally accurate (sensitivity 94%, specificity 97%, PPV 88%, NPV 98%). The Dotblot and Phadia ELiA on anti-GBM, anti-PR3(s) and anti-MPO(s) performed excellently; results were almost identical to routine ELISA. When suspicion of AAV or anti-GBM disease is high and diagnosis is urgently needed, both tests are very powerful for rapid serological diagnosis. Further studies have to confirm the test performances in samples routinely presented for ANCA testing and in follow-up of positive patients. Copyright © 2013 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Expanding Access to Malaria Diagnosis through Retail Shops in Western Kenya: What Do Shop Workers Think?

PubMed

Rusk, Andria; Goodman, Catherine; Naanyu, Violet; Koech, Beatrice; Obala, Andrew; O'Meara, Wendy Prudhomme

2013-01-01

Background. The common symptoms of malaria reduce the specificity of clinical diagnosis. Presumptive treatment is conventional but can lead to overdiagnosis of malaria, delay of appropriate treatment, overprescription of antimalarials, and drug resistance. Routine use of diagnostic tests can address many of these concerns. Though treatment is often procured from retailers, there is low availability of rapid diagnostic tests for malaria (MRDTs), a simple, inexpensive, and accurate diagnostic solution. We know little about the challenges to expanding access to diagnostics through these outlets. Methods. To understand the perceptions of the benefits and challenges to selling rapid diagnostic tests for malaria, we conducted focus group discussions with antimalarial retailers who serve the residents of the Webuye Health and Demographic Surveillance Site in western Kenya. Results. Medicine retailers perceived MRDTs to be beneficial to their customers and businesses but also included cost, fear of the tests, risks of self-treatment, and regulatory concerns among the challenges to using and selling MRDTs. Conclusion. MRDTs represent a viable approach to increase access to malaria diagnostic testing. Medicine retailers are eager for MRDTs to be made available to them. However, certain challenges remain to implementation in retail outlets and should be addressed in advance.

The Effect of Mycobacterium avium Complex Infections on Routine Mycobacterium bovis Diagnostic Tests

PubMed Central

Barry, Claire; Corbett, David; Bakker, Douwe; Andersen, Peter; McNair, Jim; Strain, Sam

2011-01-01

Bovine tuberculosis (bTB) is diagnosed in naturally infected populations exposed to a wide variety of other pathogens. This study describes the cell-mediated immune responses of cattle exposed to Mycobacterium avium subspecies paratuberculosis (Map) and Mycobacterium avium subspecies avium with particular reference to routine antefmortem Mycobacterium bovis diagnostic tests. The IFN-γ released in response to stimulated blood was found to peak later in the Map-exposed group and was more sustained when compared to the Maa-exposed group. There was a very close correlation between the responses to the purified protein derivatives (PPD) used for stimulation (PPDa, PPDb, and PPDj) with PPDa and PPDj most closely correlated. On occasion, in the Map-infected cattle, PPDb-biased responses were seen compared to PPDa suggesting that some Map-infected cattle could be misclassified as M. bovis infected using this test with these reagents. This bias was not seen when PPDj was used. SICCT results were consistent with the respective infections and all calves would have been classed skin test negative. PMID:21772961

Automated measurement of carbohydrate-deficient transferrin using the Bio-Rad %CDT by the HPLC test on a Variant HPLC system: evaluation and comparison with other routine procedures.

PubMed

Schellenberg, François; Mennetrey, Louise; Girre, Catherine; Nalpas, Bertrand; Pagès, Jean Christophe

2008-01-01

In this study, we evaluated the new %CDT by the HPLC method (Bio-Rad, Germany) on a Varianttrade mark HPLC system (Bio-Rad), checked the correlation with well-known methods and calculated the diagnostic value of the test. Intra-run and day-to-day precision values were calculated for samples with extreme serum transferrin concentrations, high trisialotransferrin and interfering conditions (haemolysed, lactescent and icteric samples). The method was compared with two routine procedures, the %CDT TIA (Bio-Rad, Hercules, CA, USA) and the Capillarystrade mark CDT (Sebia, France). A total of 350 clinical sera samples were used for a case-control study. Precision values were better in high CDT and medium CDT pools than in low CDT pools. The serum transferrin concentration had no effect on CDT measurement, except in samples with serum transferrin <1 g/L. Haemolysis was the only interfering situation. The method showed high correlation (r(2) > 0.95) with the two other methods (%CDT TIA and CZE %CDT). The global predictive value of the test was >0.90 at 1.9% cut-off. These results demonstrate that the %CDT by the HPLC test is suitable for CDT routine measurement; the results from the high-throughput Varianttrade mark system are well correlated with other methods and are of high diagnostic value.

Development of life prediction capabilities for liquid propellant rocket engines. Post-fire diagnostic system for the SSME system architecture study

NASA Technical Reports Server (NTRS)

Gage, Mark; Dehoff, Ronald

1991-01-01

This system architecture task (1) analyzed the current process used to make an assessment of engine and component health after each test or flight firing of an SSME, (2) developed an approach and a specific set of objectives and requirements for automated diagnostics during post fire health assessment, and (3) listed and described the software applications required to implement this system. The diagnostic system described is a distributed system with a database management system to store diagnostic information and test data, a CAE package for visual data analysis and preparation of plots of hot-fire data, a set of procedural applications for routine anomaly detection, and an expert system for the advanced anomaly detection and evaluation.

Specific Immunodiffusion Test for Blastomycosis

PubMed Central

Kaufman, Leo; McLaughlin, David W.; Clark, Maxine J.; Blumer, Sharon

1973-01-01

A specific immunodiffusion test for blastomycosis has been developed. The test permitted the detection of approximately 80% of 113 proven cases of blastomycosis. Two diagnostically important precipitins designated A and B were frequently recognized in patients with blastomycosis. Routine use of reference sera containing the A and B precipitins in immunodiffusion tests would permit the specific diagnosis of blastomycosis without the need for parallel tests with coccidioidin and histoplasmin. Images PMID:4201639

Diagnostic impact of routine Lyme serology in recent-onset arthritis: results from the ESPOIR cohort

PubMed Central

Guellec, Dewi; Narbonne, Valérie; Cornec, Divi; Marhadour, Thierry; Varache, Sophie; Dougados, Maxime; Daurès, Jean Pierre; Jousse-Joulin, Sandrine; Devauchelle-Pensec, Valérie; Saraux, Alain

2016-01-01

Objectives Lyme disease may be considered by rheumatologists in patients with recent-onset arthritis, even in the absence of suggestive symptoms. The aim of this study was to determine the diagnostic impact of routine Lyme serology in a French cohort of patients with recent-onset arthritis affecting at least 2 joints. Methods We performed an ancillary study of a French prospective multicentre cohort established to monitor clinical, biological and radiographic data in patients with inflammatory arthritis in at least 2 joints, lasting for 6 weeks to 6 months. Borrelia IgM and IgG antibodies were sought routinely at baseline, using ELISA tests, independently from the physician's strategy for detecting a spirochetal infection. We recorded the proportion of patients with a final diagnosis of Lyme arthritis and evaluated the diagnostic performance of Lyme serology in this particular context. The clinical and biological characteristics of patients according to the Lyme serology results were analysed. Results Of 810 patients, 657 (81.1%) were negative for IgM and IgG antibodies, 91 (11.2%) had only IgM antibodies, 49 (6%) had only IgG antibodies, and 13 (1.6%) had IgG and IgM antibodies. Thus, 7.6% had IgG positivity, consistent with exposure to Borrelia infection. IgG positivity was significantly more prevalent in the North and North-East regions of France (χ2=14.6, p<0.001). No patients received a definite diagnosis of Lyme arthritis. Conclusions This study does not support routine Lyme serological testing in patients with recent-onset inflammatory arthritis affecting more than 1 joint. PMID:26819751

(13)C breath tests in personalized medicine: fiction or reality?

PubMed

Modak, Anil S

2009-11-01

The concept of personalized medicine is gathering momentum as various biomarkers are being discovered and developed to lead to genotype and phenotype diagnostic tests, which will enable physicians to individualize therapy. Noninvasive, rapid (13)C breath tests have the potential to serve as clinically significant diagnostic tools, especially for evaluating the enzyme activity of polymorphic enzymes. This would enable physicians to rapidly identify responders/nonresponders to various drugs primarily metabolized by these enzymes prior to initiation of therapy. With the information on enzyme activity, the physician can prescribe the right drug, at the right dose, at the right time, to the right individual, for the right clinical outcome. However, the promise of the era of personalized medicine, including the novel (13)C breath tests, will have to overcome several regulatory, business and financial hurdles for diagnostic tests to become part of routine mainstream clinical practice over the next decade.

Diagnostic grand rounds: a new teaching concept to train diagnostic reasoning.

PubMed

Stieger, Stefan; Praschinger, Andrea; Kletter, Kurt; Kainberger, Franz

2011-06-01

Diagnostic reasoning is a core skill in teaching and learning in undergraduate curricula. Diagnostic grand rounds (DGRs) as a subform of grand rounds are intended to train the students' skills in the selection of appropriate tests and in the interpretation of test results. The aim of this study was to test DGRs for their ability to improve diagnostic reasoning by using a pre-post-test design. During one winter term, all 398 fifth-year students (36.1% male, 63.9% female) solved 23 clinical cases presented in 8 DGRs. In an online questionnaire, a Diagnostic Thinking Inventory (DTI) with 41 items was evaluated for flexibility in thinking and structure of knowledge in memory. Results were correlated with those from a summative multiple-choice knowledge test and of the learning objectives in a logbook. The students' DTI scores in the post-test were significantly higher than those reported in the pre-test. DTI scores at either testing time did not correlate with medical knowledge as assessed by a multiple-choice knowledge test. Abilities acquired during clinical clerkships as documented in a logbook could only account for a small proportion of the increase in the flexibility subscale score. This effect still remained significant after accounting for potential confounders. Establishing DGRs proofed to be an effective way of successfully improving both students' diagnostic reasoning and the ability to select the appropriate test method in routine clinical practice. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

Evaluation of selected clinical and diagnostic parameters in girls with anorexia nervosa (I).

PubMed

Nogal, Paweł; Pniewska-Siark, Barbara; Lewiński, Andrzej

2008-08-01

Body weight loss in patients with anorexia nervosa (AN) is accompanied by a number of hormonal and metabolic disorders. The scope and intensity of these disorders may have a considerable influence on the prognosis in this disease. The goal of the study was an evaluation of selected diagnostic examinations in comparison with clinical data of female patients with AN. Retrospective studies involved eighty-seven (87) patients with AN. On therapy commencement, routine laboratory tests (full blood cell count, serum concentrations of sodium, potassium, glucose, cholesterol, triglycerides, total calcium, phosphates, total protein and the urea) and hormonal tests (TSH, TSH, FT4, FT3, E2, T, cortisol measured at 8(00), 17(00) and 24(00), LH and FSH in stimulation test with GnRH) were performed in each patient. Correlations were determined between clinical data and the measured hormone concentrations. In the studied girls, the mean values of routine laboratory tests, performed at the beginning of the therapy, were within the normal ranges (except hypernatremia). The mean concentrations of LH, FSH and FT4 were below reference values; the mean concentration of cortisol considerably exceeded the standard range. Statistically significant relations were demonstrated between BMI values and the concentrations of LH, E2 and cortisol. Body weigh loss is not significantly reflected by abnormal results of routinely performed laboratory tests. Hypogonadotropic hypogonadism and hypercortisolemia are the most characteristic hormonal symptoms in girls with AN.

Evaluation of a PfHRP2 and a pLDH-based Rapid Diagnostic Test for the Diagnosis of Severe Malaria in 2 Populations of African Children

PubMed Central

Hendriksen, Ilse C. E.; Mtove, George; Pedro, Alínia José; Gomes, Ermelinda; Silamut, Kamolrat; Lee, Sue J.; Mwambuli, Abraham; Gesase, Samwel; Reyburn, Hugh; Day, Nicholas P. J.; White, Nicholas J.; von Seidlein, Lorenz

2011-01-01

Background. Rapid diagnostic tests (RDTs) now play an important role in the diagnosis of falciparum malaria in many countries where the disease is endemic. Although these tests have been extensively evaluated in uncomplicated falciparum malaria, reliable data on their performance for diagnosing potentially lethal severe malaria is lacking. Methods. We compared a Plasmodium falciparum histidine-rich-protein2 (PfHRP2)–based RDT and a Plasmodium lactate dehydrogenase (pLDH)–based RDT with routine microscopy of a peripheral blood slide and expert microscopy as a reference standard for the diagnosis of severe malaria in 1898 children who presented with severe febrile illness at 2 centers in Mozambique and Tanzania. Results. The overall sensitivity, specificity, positive predictive value, and negative predictive values of the PfHRP2-based test were 94.0%, 70.9%, 85.4%, and 86.8%, respectively, and for the pLDH-based test, the values were 88.0%, 88.3%, 93.2%, and 80.3%, respectively. At parasite counts <1000 parasites/μL (n = 173), sensitivity of the pLDH-based test was low (45.7%), compared with that of the PfHRP2-based test (69.9%). Both RDTs performed better than did the routine slide reading in a clinical laboratory as assessed in 1 of the centers. Conclusion. The evaluated PfHRP2-based RDT is an acceptable alternative to routine microscopy for diagnosing severe malaria in African children and performed better than did the evaluated pLDH-based RDT. PMID:21467015

Toward theragnostics.

PubMed

Pene, Frédéric; Courtine, Emilie; Cariou, Alain; Mira, Jean-Paul

2009-01-01

Theragnostics is a treatment strategy that combines therapeutics with diagnostics. It associates both a diagnostic test that identifies patients most likely to be helped or harmed by a new medication, and targeted drug therapy based on the test results. Bioinformatics, genomics, proteomics, and functional genomics are molecular biology tools essential for the progress of molecular theragnostics. These tools generate the genetic and protein information required for the development of diagnostic assays. Theragnostics includes a wide range of subjects, including personalized medicine, pharmacogenomics, and molecular imaging to develop efficient new targeted therapies with adequate benefit/risk to patients and a better molecular understanding of how to optimize drug selection. Furthermore, theragnostics aims to monitor the response to the treatment, to increase drug efficacy and safety. In addition, theragnostics could eliminate the unnecessary treatment of patients for whom therapy is not appropriate, resulting in significant drug cost savings for the healthcare system. However, the introduction of theragnostic tests into routine health care requires both a demonstration of cost-effectiveness and the availability of appropriate accessible testing systems. This review reports validation studies in oncology and infectious diseases that have demonstrated the benefits of such approach in well-defined subpopulations of patients, moving the field from the drug development process toward clinical practice and routine application. Theragnostics may change the usual business model of pharmaceutical companies from the classic blockbuster model toward targeted therapies.

Rapid diagnostic test for G6PD deficiency in Plasmodium vivax-infected men: a budget impact analysis based in Brazilian Amazon.

PubMed

Peixoto, Henry Maia; Brito, Marcelo Augusto Mota; Romero, Gustavo Adolfo Sierra; Monteiro, Wuelton Marcelo; de Lacerda, Marcus Vinícius Guimarães; de Oliveira, Maria Regina Fernandes

2017-01-01

The aim of this study was to estimate the incremental budget impact (IBI) of a rapid diagnostic test to detect G6PDd in male patients infected with Plasmodium vivax in the Brazilian Amazon, as compared with the routine protocol recommended in Brazil which does not include G6PDd testing. The budget impact analysis was performed from the perspective of the Brazilian health system, in the Brazilian Amazon for the years 2013, 2014 and 2015. The analysis used a decision model to compare two scenarios: the first consisting of the routine recommended in Brazil which does not include prior diagnosis of dG6PD, and the second based on the use of RDT CareStart™ G6PD (CS-G6PD) in all male subjects diagnosed with vivax malaria. The expected implementation of the diagnostic test was 30% in the first year, 70% the second year and 100% in the third year. The analysis identified negative IBIs which were progressively smaller in the 3 years evaluated. The sensitivity analysis showed that the uncertainties associated with the analytical model did not significantly affect the results. A strategy based on the use of CS-G6PD would result in better use of public resources in the Brazilian Amazon. © 2016 John Wiley & Sons Ltd.

Rational case management of malaria with a rapid diagnostic test, Paracheck Pf®, in antenatal health care in Bangui, Central African Republic.

PubMed

Manirakiza, Alexandre; Serdouma, Eugène; Heredeïbona, Luc Salva; Djalle, Djibrine; Madji, Nestor; Moyen, Methode; Soula, Georges; Le Faou, Alain; Delmont, Jean

2012-06-26

Both treatment and prevention strategies are recommended by the World Health Organization for the control of malaria during pregnancy in tropical areas. The aim of this study was to assess use of a rapid diagnostic test for prompt management of malaria in pregnancy in Bangui, Central African Republic. A cohort of 76 pregnant women was screened systematically for malaria with ParacheckPf® at each antenatal visit. The usefulness of the method was analysed by comparing the number of malaria episodes requiring treatment in the cohort with the number of prescriptions received by another group of pregnant women followed-up in routine antenatal care. In the cohort group, the proportion of positive ParacheckPf® episodes during antenatal clinics visits was 13.8%, while episodes of antimalarial prescriptions in the group which was followed-up routinely by antenatal personnel was estimated at 26.3%. Hence, the relative risk of the cohort for being prescribed an antimalarial drug was 0.53. Therefore, the attributable fraction of presumptive treatment avoided by systematic screening with ParacheckPf® was 47%. Use of a rapid diagnostic test is useful, affordable and easy for adequate treatment of malaria in pregnant women. More powerful studies of the usefulness of introducing the test into antenatal care are needed in all heath centres in the country and in other tropical areas.

Examination of Routine Practice Patterns in the Hospital Information Data Warehouse: Use of OLAP and Rough Set Analysis with Clinician Feedback

PubMed Central

Grant, Andrew; Grant, Gwyneth; Gagné, Jean; Blanchette, Carl; Comeau, Émilie; Brodeur, Guillaume; Dionne, Jonathon; Ayite, Alphonse; Synak, Piotr; Wroblewski, Jakub; Apanowitz, Cas

2001-01-01

The patient centred electronic patient record enables retrospective analysis of practice patterns as one means to assist clinicians adjust and improve their practice. An interrogation of the data-warehouse linking test use to Diagnostic Related Group (DRG) of one years data of the Sherbrooke University Hospital showed that one-third of patients used two-thirds of these diagnostic tests. Using RoughSets analysis, zones of repeated tests were demonstrated where results remained within stable limits. It was concluded that 30% of fluid and electrolyte testing was probably unnecessary. These findings led to an endorsement of changing the test request formats in the hospital information system from profiles to individual tests requiring justification.

Immunodiagnosis of toxocarosis in humans: evaluation of a new enzyme-linked immunosorbent assay kit.

PubMed Central

Jacquier, P; Gottstein, B; Stingelin, Y; Eckert, J

1991-01-01

Excretory/secretory (E/S) antigen derived from second-stage larvae of Toxocara canis maintained in defined medium in vitro has been well established worldwide for the immunodiagnosis of human toxocarosis by enzyme-linked immunosorbent assay. Such an enzyme-linked immunosorbent assay, based on the detection of human anti-T. canis (E/S antigen) serum immunoglobulin G, has recently been commercialized by Biokema-Affinity Products (Crissier-Lausanne, Switzerland). This commercial test kit was evaluated with regard to its application in a routine diagnostic laboratory and the reliability of the results. Of 78 patients with suspected clinical toxocarosis, 71 had anti-T. canis antibodies (positive serological result) corresponding to a diagnostic sensitivity of 91%; 14% of serum samples (n = 199) from patients with protozoan or with helminthic infections also showed positive reactions mainly related to infections with Trichinella, Strongyloides, and Fasciola species. An epidemiological study with 1,000 serum samples from randomly selected healthy blood donors and children in Switzerland demonstrated a seroprevalence of 2.7%. The test kit under evaluation had an overall diagnostic sensitivity of 91% and a relative specificity of 86%, the latter being related to some protozoan and helminthic infections. Because of the scarcity of such infections, potential cross-reactivity does not play a major role under the conditions found in the middle part of Europe. In conclusion, the application of the test kit provided for use in this study can be recommended for routine diagnostic use. PMID:1774303

Diagnostic accuracy, incremental yield and prognostic value of Determine TB-LAM for routine diagnostic testing for tuberculosis in HIV-infected patients requiring acute hospital admission in South Africa: a prospective cohort.

PubMed

Lawn, Stephen D; Kerkhoff, Andrew D; Burton, Rosie; Schutz, Charlotte; Boulle, Andrew; Vogt, Monica; Gupta-Wright, Ankur; Nicol, Mark P; Meintjes, Graeme

2017-03-21

We previously reported that one-third of HIV-positive adults requiring medical admission to a South African district hospital had laboratory-confirmed tuberculosis (TB) and that almost two-thirds of cases could be rapidly diagnosed using Xpert MTB/RIF-testing of concentrated urine samples obtained on the first day of admission. Implementation of urine-based, routine, point-of-care TB screening is an attractive intervention that might be facilitated by use of a simple, low-cost diagnostic tool, such as the Determine TB-LAM lateral-flow rapid test for HIV-associated TB. Sputum, urine and blood samples were systematically obtained from unselected HIV-positive adults within 24 hours of admission to a South African township hospital. Additional clinical samples were obtained during hospitalization as clinically indicated. TB was defined by the detection of Mycobacterium tuberculosis in any sample using Xpert MTB/RIF or liquid culture. The diagnostic yield, accuracy and prognostic value of urine-lipoarabinomannan (LAM) testing were determined, but urine-LAM results did not inform treatment decisions. Consecutive HIV-positive adult acute medical admissions not already receiving TB treatment (n = 427) were enrolled regardless of clinical presentation or symptoms. TB was diagnosed in 139 patients (TB prevalence 32.6%; median CD4 count 80 cells/μL). In the first 24 hours of admission, sputum (spot and/or induced) samples were obtained from 37.0% of patients and urine samples from 99.5% of patients (P < 0.001). The diagnostic yields from these specimens were 19.4% (n = 27/139) for sputum-microscopy, 26.6% (n = 37/139) for sputum-Xpert, 38.1% (n = 53/139) for urine-LAM and 52.5% (n = 73/139) for sputum-Xpert/urine-LAM combined (P < 0.01). Corresponding yields among patients with CD4 counts <100 cells/μL were 18.9%, 24.3%, 55.4% and 63.5%, respectively (P < 0.01). The diagnostic yield of urine-LAM was unrelated to respiratory symptoms, and LAM assay specificity (using a grade-2 cut-off) was 98.9% (274/277; 95% confidence interval [CI] 96.9-99.8). Among TB cases, positive urine-LAM status was strongly associated with mortality at 90 days (adjusted hazard ratio 4.20; 95% CI 1.50-11.75). Routine testing for TB in newly admitted HIV-positive adults using Determine TB-LAM to test urine provides major incremental diagnostic yield with very high specificity when used in combination with sputum testing and has important utility among those without respiratory TB symptoms and/or unable to produce sputum. The assay also rapidly identifies individuals with a poor prognosis.

[Comparison of thromboelastography and routine coagulation tests for evaluation of blood coagulation function in patients].

PubMed

Chen, Guan-Yi; Ou Yang, Xi-Lin; Wu, Jing-Hui; Wang, Li-Hua; Yang, Jin-Hua; Gu, Li-Nan; Lu, Zhu-Jie; Zhao, Xiao-Zi

2015-04-01

To investigate the correlation and consistency between thromboelastography(TEG) and routine coagulation tests, and to evaluate the value of the two methods in determining the blood coagulation of patients. The TEG, routine coagulation tests and platelet counts of 182 patients from the Intensive Care Unit(ICU) and Department of Gastroenterology in our hospital from January to September 2014 were performed and analyzed retrospectively for their correlation, Kappa identity test analysis and chi-square test, and the diagnostic sensitivity and specificity of both methods in the patients with bleeding were evaluated. The TEG R time and PT, R time and APTT showed a linear dependence (P<0.01). The relationship between the TEG K value, α-Angle, MA and Fibrinogen showed a linear dependence (P<0.001). And the relationship between the TEG K value, α-Angle, MA and the platelet count were in a linear dependent way (P<0.001). The Kappa values of the TEG R time with PT and APTT were 0.038 (P>0.05) and 0.061 (P>0.05), respectively. The chi-square test values of the TEG R time with PT and APTT were 35.309 (P<0.001) and 15.848 (P<0.001), respectively. The Fibrinogen and the TEG K value, α-Angle, MA value had statistical significance (P<0.001), with a Kappa value of 0.323, 0.288 and 0.427, respectively. The chi-square test values between Fibrinogen and the TEG K value, α-Angle, MA value were not statistically significant, with X2=1.091 (P=0.296), X2=1.361 (P=0.243), X2=0.108 (P=0.742). The Kappa values of the platelet count and the TEG K value, α-Angle, MA value were 0.379, 0.208 and 0.352, respectively, which were also statistically significant difference (P<0.001). The chi-square test values between the platelet count and the TEG K value, α-Angle, MA value showed a statistically significant difference (P<0.001), with X2=37.5, X2=37.23, X2=26.630. The diagnostic sensitivity of the two methods for the patients with bleeding was less than 50%. There was a significant correlation between some TEG parameters and routine coagulation tests, but the consistency is weak. Moreover, the diagnostic sensitivity of two methods in the patients with bleeding is low. It was concluded that the TEG cannot replace the conventional coagulation tests, and the preferable method remains uncertain which could reflect the risk of bleeding.

Diagnosis of Neisseria gonorrhoeae Using Molecular Beacon

PubMed Central

Patel, Achchhe Lal; Sonkar, Subash Chandra; Kumari, Indu; Saluja, Daman

2015-01-01

Neisseria gonorrhoeae is an important sexually transmitted diseases (STD) causing pathogen worldwide. Due to absence of an affordable diagnostic assay, routine screening of gonococcal infection becomes impossible in developing countries where infection rates are maximum. Treatment is given on the basis of symptoms alone which leads to spread of infection. Thus, development of a rapid, sensitive, specific, and PCR based visual diagnostic assay suitable for developing countries, required for better disease management, is aimed at in present study. Endocervical swabs were collected from patients visiting gynecology department of various hospitals in Delhi. In-house PCR based assay was developed and modified to visual assay using molecular beacon for end-point detection. It was evaluated against Roche AMPLICOR NG kit and rmp gene. Specificity of beacon was confirmed by competition experiments. Diagnostic test was 98.21% specific and 99.59% sensitive whereas negative and positive predicted value were 99.40% and 98.78%, respectively. We also observed that twice the concentration (2X) of premix was stable at 4°C for 4 months and dry swab samples gave concordant results with that of wet swabs. These features make the test best suitable for routine diagnosis of genital infections in developing countries. PMID:25802857

K(3)EDTA Vacuum Tubes Validation for Routine Hematological Testing.

PubMed

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Poli, Giovanni; Solero, Giovanni Pietro; Picheth, Geraldo; Guidi, Gian Cesare

2012-01-01

Background and Objective. Some in vitro diagnostic devices (e.g, blood collection vacuum tubes and syringes for blood analyses) are not validated before the quality laboratory managers decide to start using or to change the brand. Frequently, the laboratory or hospital managers select the vacuum tubes for blood collection based on cost considerations or on relevance of a brand. The aim of this study was to validate two dry K(3)EDTA vacuum tubes of different brands for routine hematological testing. Methods. Blood specimens from 100 volunteers in two different K(3)EDTA vacuum tubes were collected by a single, expert phlebotomist. The routine hematological testing was done on Advia 2120i hematology system. The significance of the differences between samples was assessed by paired Student's t-test after checking for normality. The level of statistical significance was set at P < 0.05. Results and Conclusions. Different brand's tubes evaluated can represent a clinically relevant source of variations only on mean platelet volume (MPV) and platelet distribution width (PDW). Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according to him/her technical or economical reasons for routine hematological tests.

K3EDTA Vacuum Tubes Validation for Routine Hematological Testing

PubMed Central

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Poli, Giovanni; Solero, Giovanni Pietro; Picheth, Geraldo; Guidi, Gian Cesare

2012-01-01

Background and Objective. Some in vitro diagnostic devices (e.g, blood collection vacuum tubes and syringes for blood analyses) are not validated before the quality laboratory managers decide to start using or to change the brand. Frequently, the laboratory or hospital managers select the vacuum tubes for blood collection based on cost considerations or on relevance of a brand. The aim of this study was to validate two dry K3EDTA vacuum tubes of different brands for routine hematological testing. Methods. Blood specimens from 100 volunteers in two different K3EDTA vacuum tubes were collected by a single, expert phlebotomist. The routine hematological testing was done on Advia 2120i hematology system. The significance of the differences between samples was assessed by paired Student's t-test after checking for normality. The level of statistical significance was set at P < 0.05. Results and Conclusions. Different brand's tubes evaluated can represent a clinically relevant source of variations only on mean platelet volume (MPV) and platelet distribution width (PDW). Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according to him/her technical or economical reasons for routine hematological tests. PMID:22888448

Cost-Effectiveness of One-Time Hepatitis C Screening Strategies Among Adolescents and Young Adults in Primary Care Settings.

PubMed

Assoumou, Sabrina A; Tasillo, Abriana; Leff, Jared A; Schackman, Bruce R; Drainoni, Mari-Lynn; Horsburgh, C Robert; Barry, M Anita; Regis, Craig; Kim, Arthur Y; Marshall, Alison; Saxena, Sheel; Smith, Peter C; Linas, Benjamin P

2018-01-18

High hepatitis C virus (HCV) rates have been reported in young people who inject drugs (PWID). We evaluated the clinical benefit and cost-effectiveness of testing among youth seen in communities with a high overall number of reported HCV cases. We developed a decision analytic model to project quality-adjusted life years (QALYs), costs (2016 US$), and incremental cost-effectiveness ratios (ICERs) of 9 strategies for 1-time testing among 15- to 30-year-olds seen at urban community health centers. Strategies differed in 3 ways: targeted vs routine testing, rapid finger stick vs standard venipuncture, and ordered by physician vs by counselor/tester using standing orders. We performed deterministic and probabilistic sensitivity analyses (PSA) to evaluate uncertainty. Compared to targeted risk-based testing (current standard of care), routine testing increased the lifetime medical cost by $80 and discounted QALYs by 0.0013 per person. Across all strategies, rapid testing provided higher QALYs at a lower cost per QALY gained and was always preferred. Counselor-initiated routine rapid testing was associated with an ICER of $71000/QALY gained. Results were sensitive to offer and result receipt rates. Counselor-initiated routine rapid testing was cost-effective (ICER <$100000/QALY) unless the prevalence of PWID was <0.59%, HCV prevalence among PWID was <16%, reinfection rate was >26 cases per 100 person-years, or reflex confirmatory testing followed all reactive venipuncture diagnostics. In PSA, routine rapid testing was the optimal strategy in 90% of simulations. Routine rapid HCV testing among 15- to 30-year-olds may be cost-effective when the prevalence of PWID is >0.59%. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

A clinical evaluation of placental growth factor in routine practice in high-risk women presenting with suspected pre-eclampsia and/or fetal growth restriction.

PubMed

Ormesher, L; Johnstone, E D; Shawkat, E; Dempsey, A; Chmiel, C; Ingram, E; Higgins, L E; Myers, J E

2018-03-13

To evaluate the use of plasma Placental Growth Factor (PlGF), recommended by the recent NICE guidance, in women with suspected pre-eclampsia (PE) and/or fetal growth restriction (FGR). Non-randomised prospective clinical evaluation study in high-risk antenatal clinics in a tertiary maternity unit. PlGF testing was performed in addition to routine clinical assessment in 260 women >20 weeks' gestation with chronic disease (hypertension, renal disease ± diabetes) with a change in maternal condition or in women with suspected FGR to determine the impact on clinical management. Results were revealed and standardised care pathways followed. Outcome of pregnancies with a low PlGF (<12 pg/ml and 13-100 pg/ml), impact on clinical service and the diagnostic accuracy of alternative PlGF cut-offs. 206/260 (79.2%) women had an adverse outcome (PE/birthweight < 10th centile/preterm birth). In our cohort, a low PlGF (<12 pg/ml) was associated with a shorter test-birth interval and universally (100% PPV) with an adverse pregnancy outcome, although 29/61 (47.5%) of women with PlGF < 12 pg/ml continued their pregnancy >14 days. The PlGF result altered clinical management (surveillance or timing of birth) in 196/260 (75.4%) cases. Alternative PlGF thresholds did not significantly improve diagnostic performance. Our evaluation confirms the value of PlGF as a diagnostic tool for placental dysfunction. However, low PlGF in isolation should not trigger iatrogenic delivery. Further research linking placental pathology, maternal disease and maternal PlGF levels is urgently needed before this test can be implemented in routine clinical practice. Copyright © 2018. Published by Elsevier B.V.

A review of current and future molecular diagnostic tests for use in the microbiology laboratory.

PubMed

Jannes, Geert; De Vos, Daniel

2006-01-01

Nucleic acid-based diagnostics gradually are replacing or complementing culture-based, biochemical, and immunological assays in routine microbiology laboratories. Similar to conventional tests, the first-generation deoxyribonucleic acid assays determined only a single analyte. Recent improvements in detection technologies have paved the way for the development of multiparameter assays using macroarrays or micro-arrays, while the introduction of closed-tube real-time polymerase chain reaction systems has resulted in the development of rapid microbial diagnostics with a reduced contamination risk. The use of these new molecular technologies is not restricted to detection and identification of microbial pathogens but also can be used for genotyping, allowing one to determine antibiotic resistance or to perform microbial fingerprinting.

Expanding Access to Malaria Diagnosis through Retail Shops in Western Kenya: What Do Shop Workers Think?

PubMed Central

Koech, Beatrice; Obala, Andrew; O'Meara, Wendy Prudhomme

2013-01-01

Background. The common symptoms of malaria reduce the specificity of clinical diagnosis. Presumptive treatment is conventional but can lead to overdiagnosis of malaria, delay of appropriate treatment, overprescription of antimalarials, and drug resistance. Routine use of diagnostic tests can address many of these concerns. Though treatment is often procured from retailers, there is low availability of rapid diagnostic tests for malaria (MRDTs), a simple, inexpensive, and accurate diagnostic solution. We know little about the challenges to expanding access to diagnostics through these outlets. Methods. To understand the perceptions of the benefits and challenges to selling rapid diagnostic tests for malaria, we conducted focus group discussions with antimalarial retailers who serve the residents of the Webuye Health and Demographic Surveillance Site in western Kenya. Results. Medicine retailers perceived MRDTs to be beneficial to their customers and businesses but also included cost, fear of the tests, risks of self-treatment, and regulatory concerns among the challenges to using and selling MRDTs. Conclusion. MRDTs represent a viable approach to increase access to malaria diagnostic testing. Medicine retailers are eager for MRDTs to be made available to them. However, certain challenges remain to implementation in retail outlets and should be addressed in advance. PMID:23766923

Usefulness of component resolved analysis of cat allergy in routine clinical practice.

PubMed

Eder, Katharina; Becker, Sven; San Nicoló, Marion; Berghaus, Alexander; Gröger, Moritz

2016-01-01

Cat allergy is of great importance, and its prevalence is increasing worldwide. Cat allergens and house dust mite allergens represent the major indoor allergens; however, they are ubiquitous. Cat sensitization and allergy are known risk factors for rhinitis, bronchial hyperreactivity and asthma. Thus, the diagnosis of sensitization to cats is important for any allergist. 70 patients with positive skin prick tests for cats were retrospectively compared regarding their skin prick test results, as well as their specific immunoglobulin E antibody profiles with regard to their responses to the native cat extract, rFel d 1, nFel d 2 and rFel d 4. 35 patients were allergic to cats, as determined by positive anamnesis and/or nasal provocation with cat allergens, and 35 patients exhibited clinically non-relevant sensitization, as indicated by negative anamnesis and/or a negative nasal allergen challenge. Native cat extract serology testing detected 100% of patients who were allergic to cats but missed eight patients who showed sensitization in the skin prick test and did not have allergic symptoms. The median values of the skin prick test, as well as those of the specific immunoglobulin E antibodies against the native cat extract, were significantly higher for allergic patients than for patients with clinically non-relevant sensitization. Component based diagnostic testing to rFel d 1 was not as reliable. Sensitization to nFel d 2 and rFel d 4 was seen only in individual patients. Extract based diagnostic methods for identifying cat allergy and sensitization, such as the skin prick test and native cat extract serology, remain crucial in routine clinical practice. In our study, component based diagnostic testing could not replace these methods with regard to the detection of sensitization to cats and differentiation between allergy and sensitization without clinical relevance. However, component resolved allergy diagnostic tools have individual implications, and future studies may facilitate a better understanding of its use and subsequently may improve the clinical management of allergic patients.

Isothermal multiple displacement amplification: a methodical approach enhancing molecular routine diagnostics of microcarcinomas and small biopsies.

PubMed

Mairinger, Fabian D; Walter, Robert Fh; Vollbrecht, Claudia; Hager, Thomas; Worm, Karl; Ting, Saskia; Wohlschläger, Jeremias; Zarogoulidis, Paul; Zarogoulidis, Konstantinos; Schmid, Kurt W

2014-01-01

Isothermal multiple displacement amplification (IMDA) can be a powerful tool in molecular routine diagnostics for homogeneous and sequence-independent whole-genome amplification of notably small tumor samples, eg, microcarcinomas and biopsies containing a small amount of tumor. Currently, this method is not well established in pathology laboratories. We designed a study to confirm the feasibility and convenience of this method for routine diagnostics with formalin-fixed, paraffin-embedded samples prepared by laser-capture microdissection. A total of 250 μg DNA (concentration 5 μg/μL) was generated by amplification over a period of 8 hours with a material input of approximately 25 cells, approximately equivalent to 175 pg of genomic DNA. In the generated DNA, a representation of all chromosomes could be shown and the presence of elected genes relevant for diagnosis in clinical samples could be proven. Mutational analysis of clinical samples could be performed without any difficulty and showed concordance with earlier diagnostic findings. We established the feasibility and convenience of IMDA for routine diagnostics. We also showed that small amounts of DNA, which were not analyzable with current molecular methods, could be sufficient for a wide field of applications in molecular routine diagnostics when they are preamplified with IMDA.

Non-invasive diagnostic platforms in management of non-small cell lung cancer: opportunities and challenges

PubMed Central

Pennell, Nathan A.

2017-01-01

Several non-invasive diagnostic platforms are already being incorporated in routine clinical practice in the work up and monitoring of patients with lung cancer. These approaches have great potential to improve patient selection and monitor patients while on therapy, however several challenges exist in clinical validation and standardization of such platforms. In this review, we summarize the current technologies available for non-invasive diagnostic evaluation from the blood of patients with non-small cell lung cancer (NSCLC), and discuss the technical and logistical challenges associated incorporating such testing in clinical practice. PMID:29057238

Laboratory testing in management of patients with suspected Ebolavirus disease: infection control and safety.

PubMed

Gilbert, G L

2015-08-01

If routine laboratory safety precautions are followed, the risk of laboratory-acquired infection from handling specimens from patients with Ebolavirus disease (EVD) is very low, especially in the early 'dry' stage of disease. In Australia, border screening to identify travellers returning from EVD-affected west African countries during the 2014-2015 outbreak has made it unlikely that specimens from patients with unrecognised EVD would be sent to a routine diagnostic laboratory. Australian public health and diagnostic laboratories associated with hospitals designated for the care of patients with EVD have developed stringent safety precautions for EVD diagnostic and other tests likely to be required for supportive care of the sickest (and most infectious) patients with EVD, including as wide a range of point-of-care tests as possible. However, it is important that the stringent requirements for packaging, transport and testing of specimens that might contain Ebolavirus--which is a tier 1 security sensitive biology agent--do not delay the diagnosis and appropriate management of other potentially serious but treatable infectious diseases, which are far more likely causes of a febrile illness in people returning from west Africa. If necessary, urgent haematology, biochemistry and microbiological tests can be performed safely, whilst awaiting the results of EVD tests, in a PC-2 laboratory with appropriate precautions including: use of recommended personal protective equipment (PPE) for laboratory staff; handling any unsealed specimens in a class 1 or II biosafety cabinet; using only centrifuges with sealed rotors; and safe disposal or decontamination of all used equipment and laboratory waste.

Diagnostic Evasion of Highly-Resistant Microorganisms: A Critical Factor in Nosocomial Outbreaks.

PubMed

Zhou, Xuewei; Friedrich, Alexander W; Bathoorn, Erik

2017-01-01

Highly resistant microorganisms (HRMOs) may evade screening strategies used in routine diagnostics. Bacteria that have evolved to evade diagnostic tests may have a selective advantage in the nosocomial environment. Evasion of resistance detection can result from the following mechanisms: low-level expression of resistance genes not resulting in detectable resistance, slow growing variants, mimicry of wild-type-resistance, and resistance mechanisms that are only detected if induced by antibiotic pressure. We reviewed reports on hospital outbreaks in the Netherlands over the past 5 years. Remarkably, many outbreaks including major nation-wide outbreaks were caused by microorganisms able to evade resistance detection by diagnostic screening tests. We describe various examples of diagnostic evasion by several HRMOs and discuss this in a broad and international perspective. The epidemiology of hospital-associated bacteria may strongly be affected by diagnostic screening strategies. This may result in an increasing reservoir of resistance genes in hospital populations that is unnoticed. The resistance elements may horizontally transfer to hosts with systems for high-level expression, resulting in a clinically significant resistance problem. We advise to communicate the identification of HRMOs that evade diagnostics within national and regional networks. Such signaling networks may prevent inter-hospital outbreaks, and allow collaborative development of adapted diagnostic tests.

Sequencing-based breast cancer diagnostics as an alternative to routine biomarkers.

PubMed

Rantalainen, Mattias; Klevebring, Daniel; Lindberg, Johan; Ivansson, Emma; Rosin, Gustaf; Kis, Lorand; Celebioglu, Fuat; Fredriksson, Irma; Czene, Kamila; Frisell, Jan; Hartman, Johan; Bergh, Jonas; Grönberg, Henrik

2016-11-30

Sequencing-based breast cancer diagnostics have the potential to replace routine biomarkers and provide molecular characterization that enable personalized precision medicine. Here we investigate the concordance between sequencing-based and routine diagnostic biomarkers and to what extent tumor sequencing contributes clinically actionable information. We applied DNA- and RNA-sequencing to characterize tumors from 307 breast cancer patients with replication in up to 739 patients. We developed models to predict status of routine biomarkers (ER, HER2,Ki-67, histological grade) from sequencing data. Non-routine biomarkers, including mutations in BRCA1, BRCA2 and ERBB2(HER2), and additional clinically actionable somatic alterations were also investigated. Concordance with routine diagnostic biomarkers was high for ER status (AUC = 0.95;AUC(replication) = 0.97) and HER2 status (AUC = 0.97;AUC(replication) = 0.92). The transcriptomic grade model enabled classification of histological grade 1 and histological grade 3 tumors with high accuracy (AUC = 0.98;AUC(replication) = 0.94). Clinically actionable mutations in BRCA1, BRCA2 and ERBB2(HER2) were detected in 5.5% of patients, while 53% had genomic alterations matching ongoing or concluded breast cancer studies. Sequencing-based molecular profiling can be applied as an alternative to histopathology to determine ER and HER2 status, in addition to providing improved tumor grading and clinically actionable mutations and molecular subtypes. Our results suggest that sequencing-based breast cancer diagnostics in a near future can replace routine biomarkers.

Detection of SHOX gene aberrations in routine diagnostic practice and evaluation of phenotype scoring form effectiveness.

PubMed

Hirschfeldova, Katerina; Florianova, Martina; Kebrdlova, Vera; Urbanova, Marketa; Stekrova, Jitka

2017-02-01

Heterozygous aberrations of SHOX gene have been reported to be responsible for Léri-Weill dyschondrosteosis (LWD) and small portion of idiopathic short stature. The study was established to assess effectiveness of using phenotype 'scoring form' in patients indicated for SHOX gene defect analysis. The submitted study is based on a retrospective group of 352 unrelated patients enrolled as a part of the routine diagnostic practice and analyzed for aberrations affecting the SHOX gene. All participants were scanned for deletion/duplication within the main pseudoautosomal region (PAR1) using the multiplex ligation-dependent probe amplification (MLPA) method. The phenotype 'scoring form' is used in our laboratory practice to preselect patients for subsequent mutation analysis of SHOX gene-coding sequences. The overall detection rate was 11.1% but there was a significant increase in frequency of SHOX gene defect positive with increasing achieved score (P<0.0001). The most frequent aberration was a causal deletion within PAR1. In three probands, MLPA analysis indicated a more complex rearrangement. Madelung deformity or co-occurrence of disproportionate short stature, short forearm and muscular hypertrophy had represented the most potent markers to determine the likelihood of SHOX gene defect detection. We conclude that appliance of phenotype 'scoring form' had saved excessive sample analysis and enabled effective routine diagnostic testing.

Rational case management of malaria with a rapid diagnostic test, Paracheck Pf®, in antenatal health care in Bangui, Central African Republic

PubMed Central

2012-01-01

Background Both treatment and prevention strategies are recommended by the World Health Organization for the control of malaria during pregnancy in tropical areas. The aim of this study was to assess use of a rapid diagnostic test for prompt management of malaria in pregnancy in Bangui, Central African Republic. Methods A cohort of 76 pregnant women was screened systematically for malaria with ParacheckPf® at each antenatal visit. The usefulness of the method was analysed by comparing the number of malaria episodes requiring treatment in the cohort with the number of prescriptions received by another group of pregnant women followed-up in routine antenatal care. Results In the cohort group, the proportion of positive ParacheckPf® episodes during antenatal clinics visits was 13.8%, while episodes of antimalarial prescriptions in the group which was followed-up routinely by antenatal personnel was estimated at 26.3%. Hence, the relative risk of the cohort for being prescribed an antimalarial drug was 0.53. Therefore, the attributable fraction of presumptive treatment avoided by systematic screening with ParacheckPf® was 47%. Conclusions Use of a rapid diagnostic test is useful, affordable and easy for adequate treatment of malaria in pregnant women. More powerful studies of the usefulness of introducing the test into antenatal care are needed in all heath centres in the country and in other tropical areas. PMID:22734602

How to prevent overdiagnosis.

PubMed

Chiolero, Arnaud; Paccaud, Fred; Aujesky, Drahomir; Santschi, Valérie; Rodondi, Nicolas

2015-01-01

Overdiagnosis is the diagnosis of an abnormality that is not associated with a substantial health hazard and that patients have no benefit to be aware of. It is neither a misdiagnosis (diagnostic error), nor a false positive result (positive test in the absence of a real abnormality). It mainly results from screening, use of increasingly sensitive diagnostic tests, incidental findings on routine examinations, and widening diagnostic criteria to define a condition requiring an intervention. The blurring boundaries between risk and disease, physicians' fear of missing a diagnosis and patients' need for reassurance are further causes of overdiagnosis. Overdiagnosis often implies procedures to confirm or exclude the presence of the condition and is by definition associated with useless treatments and interventions, generating harm and costs without any benefit. Overdiagnosis also diverts healthcare professionals from caring about other health issues. Preventing overdiagnosis requires increasing awareness of healthcare professionals and patients about its occurrence, the avoidance of unnecessary and untargeted diagnostic tests, and the avoidance of screening without demonstrated benefits. Furthermore, accounting systematically for the harms and benefits of screening and diagnostic tests and determining risk factor thresholds based on the expected absolute risk reduction would also help prevent overdiagnosis.

Performance Evaluation of the Elecsys Syphilis Assay for the Detection of Total Antibodies to Treponema pallidum

PubMed Central

Enders, Martin; Hunjet, Andrea; Gleich, Michael; Imdahl, Roland; Mühlbacher, Annelies; Schennach, Harald; Chaiwong, Kriangsak; Sakuldamrongpanich, Tasanee; Turhan, Ajda; Sertöz, Rüchan; Wolf, Eva; Mayer, Wolfgang; Tao, Chuanmin; Wang, Lan Lan; Semprini, Simona

2014-01-01

Syphilis is a health problem of increasing incidence in recent years that may have severe complications if not diagnosed and treated at an early stage. There are many diagnostic tests available for syphilis, but there is no gold standard, and diagnosis therefore usually relies upon a combination of tests. In this multicenter study, we evaluated the treponemal Elecsys syphilis assay for use in the diagnosis of syphilis in routine samples, i.e., when syphilis is suspected or during antenatal or blood donation screening. The sensitivity and specificity of the Elecsys syphilis assay were compared head to head with those of other treponemal assays used in routine clinical practice and were assessed in potentially cross-reactive samples from patients with Epstein-Barr virus, HIV, and Lyme disease. In a total of 8,063 syphilis-negative samples collected from routine diagnostic requests and blood donations, the Elecsys syphilis assay had a specificity of 99.88%. In 928 samples previously identified as syphilis positive, the sensitivity was 99.57 to 100% (the result is presented as a range depending on whether four initially indeterminate samples are included in the assessment). The specificity of the Elecsys syphilis assay in patients with other infections was 100%; no false-positive samples were identified. PMID:25355799

Can electronic medical images replace hard-copy film? Defining and testing the equivalence of diagnostic tests.

PubMed

Obuchowski, N A

2001-10-15

Electronic medical images are an efficient and convenient format in which to display, store and transmit radiographic information. Before electronic images can be used routinely to screen and diagnose patients, however, it must be shown that readers have the same diagnostic performance with this new format as traditional hard-copy film. Currently, there exist no suitable definitions of diagnostic equivalence. In this paper we propose two criteria for diagnostic equivalence. The first criterion ('population equivalence') considers the variability between and within readers, as well as the mean reader performance. This criterion is useful for most applications. The second criterion ('individual equivalence') involves a comparison of the test results for individual patients and is necessary when patients are followed radiographically over time. We present methods for testing both individual and population equivalence. The properties of the proposed methods are assessed in a Monte Carlo simulation study. Data from a mammography screening study is used to illustrate the proposed methods and compare them with results from more conventional methods of assessing equivalence and inter-procedure agreement. Copyright 2001 John Wiley & Sons, Ltd.

Most routine laboratory testing of pediatric psychiatric patients in the emergency department is not medically necessary.

PubMed

Donofrio, J Joelle; Horeczko, Timothy; Kaji, Amy; Santillanes, Genevieve; Claudius, Ilene

2015-05-01

We examined the patient characteristics and hospital charges associated with routine medical clearance laboratory screening tests in 1,082 children younger than age eighteen who were brought to the emergency department (ED) for involuntary mental health holds--that is, each patient was brought to the ED to be evaluated for being a danger to him- or herself or to others, for being gravely disabled (unable to meet his or her basic needs due to a mental disorder), or both--from July 2009 to December 2010. Testing was performed on 871 of the children; all patients also received a clinical examination. The median charge for blood and urine testing together was $1,235, and the most frequent ordering pattern was the full comprehensive panel of tests. Of the patients with a nonconcerning clinical examination, 94.3 percent also had clinically nonsignificant test results. When we extrapolated cost savings to the national level, omitting routine screening laboratory tests in the population of pediatric patients presenting to the ED on an involuntary psychiatric hold with nonconcerning clinical exams could represent up to $90 million in savings annually, without reducing the ability to screen for emergency medical conditions. Provider-initiated diagnostic testing instead of routine screening would lead to significantly lower charges to the ED and the patient. Project HOPE—The People-to-People Health Foundation, Inc.

An update on the use of cerebrospinal fluid analysis as a diagnostic tool in multiple sclerosis.

PubMed

Gastaldi, Matteo; Zardini, Elisabetta; Franciotta, Diego

2017-01-01

Intrathecal B-lymphocyte activation is a hallmark of multiple sclerosis (MS), a multi-factorial inflammatory-demyelinating disease of the central nervous system. Such activation has a counterpart in the cerebrospinal fluid (CSF) oligoclonal IgG bands (OCB), whose diagnostic role in MS has been downgraded within the current McDonald's criteria. With a theoretico-practical approach, the authors review the physiopathological basis of the CSF dynamics, and the state-of-the-art of routine CSF analysis and CSF biomarkers in MS. Areas covered: The authors discuss pros and cons of CSF analysis, including critical evaluations of both well-established, and promising diagnostic and prognostic laboratory tools. New acquisitions on the CSF and cerebral interstitial fluid dynamics are also presented. The authors searched the PubMed database for English-language articles reported between January 2010 and June 2016, using the key words 'multiple sclerosis', 'cerebrospinal fluid', 'oligoclonal bands'. Reference lists of relevant articles were scanned for additional studies. Expert commentary: The availability of performing high-quality, routine CSF tests in specialized laboratories, the emerging potential of novel CSF biomarkers, and the trend for early treatments should induce a reappraisal of CSF analysis for diagnostic and prognostic purposes in MS. Further procedural and methodological improvements seem to be necessary in both research and translational diagnostic CSF settings.

Evaluation of the Performance of Five Diagnostic Tests for Fasciola hepatica Infection in Naturally Infected Cattle Using a Bayesian No Gold Standard Approach.

PubMed

Mazeri, Stella; Sargison, Neil; Kelly, Robert F; Bronsvoort, Barend M deC; Handel, Ian

2016-01-01

The clinical and economic importance of fasciolosis has been recognised for centuries, yet diagnostic tests available for cattle are far from perfect. Test evaluation has mainly been carried out using gold standard approaches or under experimental settings, the limitations of which are well known. In this study, a Bayesian no gold standard approach was used to estimate the diagnostic sensitivity and specificity of five tests for fasciolosis in cattle. These included detailed liver necropsy including gall bladder egg count, faecal egg counting, a commercially available copro-antigen ELISA, an in-house serum excretory/secretory antibody ELISA and routine abattoir liver inspection. In total 619 cattle slaughtered at one of Scotland's biggest abattoirs were sampled, during three sampling periods spanning summer 2013, winter 2014 and autumn 2014. Test sensitivities and specificities were estimated using an extension of the Hui Walter no gold standard model, where estimates were allowed to vary between seasons if tests were a priori believed to perform differently for any reason. The results of this analysis provide novel information on the performance of these tests in a naturally infected cattle population and at different times of the year where different levels of acute or chronic infection are expected. Accurate estimates of sensitivity and specificity will allow for routine abattoir liver inspection to be used as a tool for monitoring the epidemiology of F. hepatica as well as evaluating herd health planning. Furthermore, the results provide evidence to suggest that the copro-antigen ELISA does not cross-react with Calicophoron daubneyi rumen fluke parasites, while the serum antibody ELISA does.

In-situ material-motion diagnostics and fuel radiography in experimental reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeVolpi, A.

1982-01-01

Material-motion monitoring has become a routine part of in-pile transient reactor-safety experiments. Diagnostic systems, such as the fast-neutron hodoscope, were developed for the purpose of providing direct time-resolved data on pre-failure fuel motion, cladding-breach time and location, and post-failure fuel relocation. Hodoscopes for this purpose have been installed at TREAT and CABRI; other types of imaging systems that have been tested are a coded-aperture at ACRR and a pinhole at TREAT. Diagnostic systems that use penetrating radiation emitted from the test section can non-invasively monitor fuel without damage to the measuring instrument during the radiographic images of test sections installedmore » in the reator. Studies have been made of applications of hodoscopes to other experimental reactors, including PBF, FARET, STF, ETR, EBR-II, SAREF-STF, and DMT.« less

Acute undifferentiated fever in India: a multicentre study of aetiology and diagnostic accuracy.

PubMed

Mørch, Kristine; Manoharan, Anand; Chandy, Sara; Chacko, Novin; Alvarez-Uria, Gerardo; Patil, Suvarna; Henry, Anil; Nesaraj, Joel; Kuriakose, Cijoy; Singh, Ashita; Kurian, Siby; Gill Haanshuus, Christel; Langeland, Nina; Blomberg, Bjørn; Vasanthan Antony, George; Mathai, Dilip

2017-10-04

The objectives of this study were to determine the proportion of malaria, bacteraemia, scrub typhus, leptospirosis, chikungunya and dengue among hospitalized patients with acute undifferentiated fever in India, and to describe the performance of standard diagnostic methods. During April 2011-November 2012, 1564 patients aged ≥5 years with febrile illness for 2-14 days were consecutively included in an observational study at seven community hospitals in six states in India. Malaria microscopy, blood culture, Dengue rapid NS1 antigen and IgM Combo test, Leptospira IgM ELISA, Scrub typhus IgM ELISA and Chikungunya IgM ELISA were routinely performed at the hospitals. Second line testing, Dengue IgM capture ELISA (MAC-ELISA), Scrub typhus immunofluorescence (IFA), Leptospira Microscopic Agglutination Test (MAT), malaria PCR and malaria immunochromatographic rapid diagnostic test (RDT) Parahit Total™ were performed at the coordinating centre. Convalescence samples were not available. Case definitions were as follows: Leptospirosis: Positive ELISA and positive MAT. Scrub typhus: Positive ELISA and positive IFA. Dengue: Positive RDT and/or positive MAC-ELISA. Chikungunya: Positive ELISA. Bacteraemia: Growth in blood culture excluding those defined as contaminants. Malaria: Positive genus-specific PCR. Malaria was diagnosed in 17% (268/1564) and among these 54% had P. falciparum. Dengue was diagnosed in 16% (244/1564). Bacteraemia was found in 8% (124/1564), and among these Salmonella typhi or S. paratyphi constituted 35%. Scrub typhus was diagnosed in 10%, leptospirosis in 7% and chikungunya in 6%. Fulfilling more than one case definition was common, most frequent in chikungunya where 26% (25/98) also had positive dengue test. Malaria and dengue were the most common causes of fever in this study. A high overlap between case definitions probably reflects high prevalence of prior infections, cross reactivity and subclinical infections, rather than high prevalence of coinfections. Low accuracy of routine diagnostic tests should be taken into consideration when approaching the patient with acute undifferentiated fever in India.

Non-invasive prenatal testing (NIPT): Europe's first multicenter post-market clinical follow-up study validating the quality in clinical routine.

PubMed

Flöck, Anne; Tu, Ngoc-Chi; Rüland, Anna; Holzgreve, Wolfgang; Gembruch, Ulrich; Geipel, Annegret

2017-11-01

Non-invasive prenatal tests (NIPT) for the determination of fetal aneuploidies from maternal blood are firmly established in clinical routine. For the first time, the accuracy of an NIPT for the determination of trisomies 21, 18 and 13 in singleton pregnancies was assessed by means of a prospective German-wide multicenter post-market clinical follow-up study, to reliably evaluate the quality in clinical routine. The study covered the indications for testing, the test results, the rate of invasive diagnostics and the pregnancy outcome. 2232 cases were tested for trisomy 21. Of these, 1946 cases were additionally examined for trisomy 18 and 13. Sensitivity and specificity for trisomy 21 (43/43) and for trisomy 13 (2/2) were 100%, for trisomy 18 the sensitivity was 80% (4/5) with a specificity of 99.8%. Three false-positive results for trisomy 18 were observed (FPR 0.15%). The no-call rate was 0.5%. In this subgroup, 27.3% (3/11) aneuploidies were diagnosed. The rate of invasive procedures was 2.6%. NIPT provides a very high quality for the fetal trisomies 21, 13 and 18 in clinical routine. The results support the recommendation that NIPT should be offered after genetic counseling and only in conjunction with a qualified ultrasound examination.

Diagnostic accuracy of physical examination tests of the ankle/foot complex: a systematic review.

PubMed

Schwieterman, Braun; Haas, Deniele; Columber, Kirby; Knupp, Darren; Cook, Chad

2013-08-01

Orthopedic special tests of the ankle/foot complex are routinely used during the physical examination process in order to help diagnose ankle/lower leg pathologies. The purpose of this systematic review was to investigate the diagnostic accuracy of ankle/lower leg special tests. A search of the current literature was conducted using PubMed, CINAHL, SPORTDiscus, ProQuest Nursing and Allied Health Sources, Scopus, and Cochrane Library. Studies were eligible if they included the following: 1) a diagnostic clinical test of musculoskeletal pathology in the ankle/foot complex, 2) description of the clinical test or tests, 3) a report of the diagnostic accuracy of the clinical test (e.g. sensitivity and specificity), and 4) an acceptable reference standard for comparison. The quality of included studies was determined by two independent reviewers using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Nine diagnostic accuracy studies met the inclusion criteria for this systematic review; analyzing a total of 16 special tests of the ankle/foot complex. After assessment using the QUADAS-2, only one study had low risk of bias and low concerns regarding applicability. Most ankle/lower leg orthopedic special tests are confirmatory in nature and are best utilized at the end of the physical examination. Most of the studies included in this systematic review demonstrate notable biases, which suggest that results and recommendations in this review should be taken as a guide rather than an outright standard. There is need for future research with more stringent study design criteria so that more accurate diagnostic power of ankle/lower leg special tests can be determined. 3a.

DIAGNOSTIC ACCURACY OF PHYSICAL EXAMINATION TESTS OF THE ANKLE/FOOT COMPLEX: A SYSTEMATIC REVIEW

PubMed Central

Schwieterman, Braun; Haas, Deniele; Columber, Kirby; Knupp, Darren

2013-01-01

Background: Orthopedic special tests of the ankle/foot complex are routinely used during the physical examination process in order to help diagnose ankle/lower leg pathologies. Purpose: The purpose of this systematic review was to investigate the diagnostic accuracy of ankle/lower leg special tests. Methods: A search of the current literature was conducted using PubMed, CINAHL, SPORTDiscus, ProQuest Nursing and Allied Health Sources, Scopus, and Cochrane Library. Studies were eligible if they included the following: 1) a diagnostic clinical test of musculoskeletal pathology in the ankle/foot complex, 2) description of the clinical test or tests, 3) a report of the diagnostic accuracy of the clinical test (e.g. sensitivity and specificity), and 4) an acceptable reference standard for comparison. The quality of included studies was determined by two independent reviewers using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Results: Nine diagnostic accuracy studies met the inclusion criteria for this systematic review; analyzing a total of 16 special tests of the ankle/foot complex. After assessment using the QUADAS-2, only one study had low risk of bias and low concerns regarding applicability. Conclusion: Most ankle/lower leg orthopedic special tests are confirmatory in nature and are best utilized at the end of the physical examination. Most of the studies included in this systematic review demonstrate notable biases, which suggest that results and recommendations in this review should be taken as a guide rather than an outright standard. There is need for future research with more stringent study design criteria so that more accurate diagnostic power of ankle/lower leg special tests can be determined. Level of Evidence: 3a PMID:24175128

Efficient strategies to find diagnostic test accuracy studies in kidney journals.

PubMed

Rogerson, Thomas E; Ladhani, Maleeka; Mitchell, Ruth; Craig, Jonathan C; Webster, Angela C

2015-08-01

Nephrologists looking for quick answers to diagnostic clinical questions in MEDLINE can use a range of published search strategies or Clinical Query limits to improve the precision of their searches. We aimed to evaluate existing search strategies for finding diagnostic test accuracy studies in nephrology journals. We assessed the accuracy of 14 search strategies for retrieving diagnostic test accuracy studies from three nephrology journals indexed in MEDLINE. Two investigators hand searched the same journals to create a reference set of diagnostic test accuracy studies to compare search strategy results against. We identified 103 diagnostic test accuracy studies, accounting for 2.1% of all studies published. The most specific search strategy was the Narrow Clinical Queries limit (sensitivity: 0.20, 95% CI 0.13-0.29; specificity: 0.99, 95% CI 0.99-0.99). Using the Narrow Clinical Queries limit, a searcher would need to screen three (95% CI 2-6) articles to find one diagnostic study. The most sensitive search strategy was van der Weijden 1999 Extended (sensitivity: 0.95; 95% CI 0.89-0.98; specificity 0.55, 95% CI 0.53-0.56) but required a searcher to screen 24 (95% CI 23-26) articles to find one diagnostic study. Bachmann 2002 was the best balanced search strategy, which was sensitive (0.88, 95% CI 0.81-0.94), but also specific (0.74, 95% CI 0.73-0.75), with a number needed to screen of 15 (95% CI 14-17). Diagnostic studies are infrequently published in nephrology journals. The addition of a strategy for diagnostic studies to a subject search strategy in MEDLINE may reduce the records needed to screen while preserving adequate search sensitivity for routine clinical use. © 2015 Asian Pacific Society of Nephrology.

Comparison of a New and Rapid Method: Brucella Coombs Gel Test With Other Diagnostic Tests.

PubMed

Kalem, Fatma; Ergün, Ayşe Gül; Durmaz, Süleyman; Doğan, Metin; Ertuğrul, Ömür; Gündem, Seval

2016-09-01

The aim of this study was to detect reliability of Brucella Coombs gel test (BCGT) by comparing with with ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination methods in serological diagnosis of brucellosis. Brucella Coombs gel test (BCGT), Brucella ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination tests of 78 patients with presumptive diagnosis of brucellosis which were sent to Microbiology Laboratory of Konya Numune Hospital from various regions of Konya were studied. Of 78 patients with ELISA IgG and IgM, STA, BICA and BCGT; 26, 21, 10, 12 and 12 were positive. When compared with BICA, the sensitivity and specifity of BCGT were 100% and 100%, respectively. According to results BCGT can be used as a diagnostic test in routine laboratories after more comprehensive studies in control groups and patients. © 2016 Wiley Periodicals, Inc.

Performance of amplicon-based next generation DNA sequencing for diagnostic gene mutation profiling in oncopathology.

PubMed

Sie, Daoud; Snijders, Peter J F; Meijer, Gerrit A; Doeleman, Marije W; van Moorsel, Marinda I H; van Essen, Hendrik F; Eijk, Paul P; Grünberg, Katrien; van Grieken, Nicole C T; Thunnissen, Erik; Verheul, Henk M; Smit, Egbert F; Ylstra, Bauke; Heideman, Daniëlle A M

2014-10-01

Next generation DNA sequencing (NGS) holds promise for diagnostic applications, yet implementation in routine molecular pathology practice requires performance evaluation on DNA derived from routine formalin-fixed paraffin-embedded (FFPE) tissue specimens. The current study presents a comprehensive analysis of TruSeq Amplicon Cancer Panel-based NGS using a MiSeq Personal sequencer (TSACP-MiSeq-NGS) for somatic mutation profiling. TSACP-MiSeq-NGS (testing 212 hotspot mutation amplicons of 48 genes) and a data analysis pipeline were evaluated in a retrospective learning/test set approach (n = 58/n = 45 FFPE-tumor DNA samples) against 'gold standard' high-resolution-melting (HRM)-sequencing for the genes KRAS, EGFR, BRAF and PIK3CA. Next, the performance of the validated test algorithm was assessed in an independent, prospective cohort of FFPE-tumor DNA samples (n = 75). In the learning set, a number of minimum parameter settings was defined to decide whether a FFPE-DNA sample is qualified for TSACP-MiSeq-NGS and for calling mutations. The resulting test algorithm revealed 82% (37/45) compliance to the quality criteria and 95% (35/37) concordant assay findings for KRAS, EGFR, BRAF and PIK3CA with HRM-sequencing (kappa = 0.92; 95% CI = 0.81-1.03) in the test set. Subsequent application of the validated test algorithm to the prospective cohort yielded a success rate of 84% (63/75), and a high concordance with HRM-sequencing (95% (60/63); kappa = 0.92; 95% CI = 0.84-1.01). TSACP-MiSeq-NGS detected 77 mutations in 29 additional genes. TSACP-MiSeq-NGS is suitable for diagnostic gene mutation profiling in oncopathology.

Sodium citrate vacuum tubes validation: preventing preanalytical variability in routine coagulation testing.

PubMed

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Picheth, Geraldo; Guidi, Gian Cesare

2013-04-01

Sometimes in-vitro diagnostic devices (e.g. blood collection tubes) are not validated before use or when the producer's brand is changed. The aim of this study was to validate five brands of sodium citrate vacuum tubes. Blood specimens from 50 volunteers were collected in five different tube brands (I: Venosafe, II: VACUETTE, III: BD Vacutainer, IV: LABOR IMPORT and V: S-Monovette). Routine coagulation tests [activated partial thromboplastin time (aPTT), prothrombin time (PT), and fibrinogen (FIB)] were performed on ACL TOP instrument using HemosIL reagents. The significance of the differences between samples was assessed by paired Student's t-test, set at P < 0.005. Significant differences were observed for: PT when comparing I vs. II, I vs. III, I vs. V, II vs. III, II vs. IV, II vs. V, III vs. IV, III vs. V and IV vs. V; aPTT when comparing I vs. II, I vs. III, I vs. IV, II vs. IV, III vs. IV and IV vs. V. No differences were observed among brands for FIB determination. We suggest that every laboratory management should both standardize the procedures and frequently evaluate the quality of in-vitro diagnostic devices.

miRNA assays in the clinical laboratory: workflow, detection technologies and automation aspects.

PubMed

Kappel, Andreas; Keller, Andreas

2017-05-01

microRNAs (miRNAs) are short non-coding RNA molecules that regulate gene expression in eukaryotes. Their differential abundance is indicative or even causative for a variety of pathological processes including cancer or cardiovascular disorders. Due to their important biological function, miRNAs represent a promising class of novel biomarkers that may be used to diagnose life-threatening diseases, and to monitor disease progression. Further, they may guide treatment selection or dosage of drugs. miRNAs from blood or derived fractions are particularly interesting candidates for routine laboratory applications, as they can be measured in most clinical laboratories already today. This assures a good accessibility of respective tests. Albeit their great potential, miRNA-based diagnostic tests have not made their way yet into the clinical routine, and hence no standardized workflows have been established to measure miRNAs for patients' benefit. In this review we summarize the detection technologies and workflow options that exist to measure miRNAs, and we describe the advantages and disadvantages of each of these options. Moreover, we also provide a perspective on data analysis aspects that are vital for translation of raw data into actionable diagnostic test results.

Antimicrobial susceptibility testing by Australian veterinary diagnostic laboratories.

PubMed

Hardefeldt, L Y; Marenda, M; Crabb, H; Stevenson, M A; Gilkerson, J R; Billman-Jacobe, H; Browning, G F

2018-04-01

The national strategy for tackling antimicrobial resistance highlights the need for antimicrobial stewardship in veterinary practice and for surveillance of antimicrobial susceptibility in veterinary pathogens. Diagnostic laboratories have an important role in facilitating both of these processes, but it is unclear whether data from veterinary diagnostic laboratories are similar enough to allow for compilation and if there is consistent promotion of appropriate antimicrobial use embedded in the approaches of different laboratories to susceptibility testing. A cross-sectional study of antimicrobial susceptibility testing and reporting procedures by Australian veterinary diagnostic laboratories was conducted in 2017 using an online questionnaire. All 18 veterinary diagnostic laboratories in Australia completed the questionnaire. Kirby-Bauer disc diffusion was the method predominantly used for antimicrobial susceptibility testing and was used to evaluate 86% of all isolates, although two different protocols were used across the 18 laboratories (CLSI 15/18, CDS 3/18). Minimum inhibitory concentrations were never reported by 61% of laboratories. Common isolates were consistently reported on across all species, except for gram-negative isolates in pigs, for which there was some variation in the approach to reporting. There was considerable diversity in the panels of antimicrobials used for susceptibility testing on common isolates and no consistency was apparent between laboratories for any bacterial species. We recommend that nationally agreed and consistent antimicrobial panels for routine susceptibility testing should be developed and a uniform set of guidelines should be adopted by veterinary diagnostic laboratories in Australia. © 2018 Australian Veterinary Association.

Multi-Center Evaluation of the Fully Automated PCR-Based Idylla™ KRAS Mutation Assay for Rapid KRAS Mutation Status Determination on Formalin-Fixed Paraffin-Embedded Tissue of Human Colorectal Cancer

PubMed Central

Solassol, Jérôme; Vendrell, Julie; Märkl, Bruno; Haas, Christian; Bellosillo, Beatriz; Montagut, Clara; Smith, Matthew; O’Sullivan, Brendan; D’Haene, Nicky; Le Mercier, Marie; Grauslund, Morten; Melchior, Linea Cecilie; Burt, Emma; Cotter, Finbarr; Stieber, Daniel; Schmitt, Fernando de Lander; Motta, Valentina; Lauricella, Calogero; Colling, Richard; Soilleux, Elizabeth; Fassan, Matteo; Mescoli, Claudia; Collin, Christine; Pagès, Jean-Christophe; Sillekens, Peter

2016-01-01

Since the advent of monoclonal antibodies against epidermal growth factor receptor (EGFR) in colorectal cancer therapy, the determination of RAS mutational status is needed for therapeutic decision-making. Most prevalent in colorectal cancer are KRAS exon 2 mutations (40% prevalence); lower prevalence is observed for KRAS exon 3 and 4 mutations (6%) and NRAS exon 2, 3, and 4 mutations (5%). The Idylla™ KRAS Mutation Test on the molecular diagnostics Idylla™ platform is a simple (<2 minutes hands-on time), highly reliable, and rapid (approximately 2 hours turnaround time) in vitro diagnostic sample-to-result solution. This test enables qualitative detection of 21 mutations in codons 12, 13, 59, 61, 117, and 146 of the KRAS oncogene being clinically relevant according to the latest clinical guidelines. Here, the performance of the Idylla™ KRAS Mutation Assay, for Research Use Only, was assessed on archived formalin-fixed paraffin-embedded (FFPE) tissue sections by comparing its results with the results previously obtained by routine reference approaches for KRAS genotyping. In case of discordance, samples were assessed further by additional methods. Among the 374 colorectal cancer FFPE samples tested, the overall concordance between the Idylla™ KRAS Mutation Assay and the confirmed reference routine test results was found to be 98.9%. The Idylla™ KRAS Mutation Assay enabled detection of 5 additional KRAS-mutated samples not detected previously with reference methods. As conclusion the Idylla™ KRAS Mutation Test can be applied as routine tool in any clinical setting, without needing molecular infrastructure or expertise, to guide the personalized treatment of colorectal cancer patients. PMID:27685259

Performance of a Highly Sensitive Mycobacterium tuberculosis Complex Real-Time PCR Assay for Diagnosis of Pulmonary Tuberculosis in a Low-Prevalence Setting: a Prospective Intervention Study.

PubMed

Vinuesa, Víctor; Borrás, Rafael; Briones, María Luisa; Clari, María Ángeles; Cresencio, Vicenta; Giménez, Estela; Muñoz, Carmen; Oltra, Rosa; Servera, Emilio; Scheelje, Talia; Tornero, Carlos; Navarro, David

2018-05-01

The potential impact of routine real-time PCR testing of respiratory specimens from patients with presumptive tuberculosis in terms of diagnostic accuracy and time to tuberculosis treatment inception in low-prevalence settings remains largely unexplored. We conducted a prospective intervention cohort study. Respiratory specimens from 1,020 patients were examined by acid-fast bacillus smear microscopy, tested by a real-time Mycobacterium tuberculosis complex PCR assay (Abbott RealTi me MTB PCR), and cultured in mycobacterial media. Seventeen patients tested positive by PCR (5 were acid-fast bacillus smear positive and 12 acid-fast bacillus smear negative), and Mycobacterium tuberculosis was recovered from cultures for 12 of them. Patients testing positive by PCR and negative by culture ( n = 5) were treated and deemed to have responded to antituberculosis therapy. There were no PCR-negative/culture-positive cases, and none of the patients testing positive for nontuberculous mycobacteria ( n = 20) yielded a positive PCR result. The data indicated that routine testing of respiratory specimens from patients with presumptive tuberculosis by the RealTi me MTB PCR assay improves the tuberculosis diagnostic yield and may reduce the time to antituberculosis treatment initiation. On the basis of our data, we propose a novel mycobacterial laboratory algorithm for tuberculosis diagnosis. Copyright © 2018 American Society for Microbiology.

Physician consideration of patients' out-of-pocket costs in making common clinical decisions.

PubMed

Pham, Hoangmai H; Alexander, G Caleb; O'Malley, Ann S

2007-04-09

Patients face growing cost-sharing through higher deductibles and other out-of-pocket (OP) expenses, with uncertain effects on clinical decision making. We analyzed data on 6628 respondents to the nationally representative 2004-2005 Community Tracking Study Physician Survey to examine how frequently physicians report considering their insured patients' OP expenses when prescribing drugs, selecting diagnostic tests, and choosing inpatient vs outpatient care settings. Responses were dichotomized as always/usually vs sometimes/rarely/never. In separate multivariate logistic regressions, we examined associations between physicians' reported frequency of considering OP costs for each type of decision and characteristics of individual physicians and their practices. Seventy-eight percent of physicians reported routinely considering OP costs when prescribing drugs, while 51.2% reported doing so when selecting care settings, and 40.2% when selecting diagnostic tests. In adjusted analyses, primary care physicians were more likely than medical specialists to consider patients' OP costs in choosing prescription drugs (85.3% vs 74.5%) (P<.001), care settings (53.9% vs 43.1%) (P<.001), and diagnostic tests (46.3% vs 29.9%) (P<.001). Physicians working in large groups or health maintenance organizations were more likely to consider OP costs in prescribing generic drugs (P<.001 for comparisons with solo and 2-person practices), but those in solo or 2-person practices were more likely to do so in choosing tests and care settings (P<.05 for all comparisons with other practice types). Physicians providing at least 10 hours of charity care a month were more likely than those not providing any to consider OP costs in both diagnostic testing (40.7% vs 35.8%) (P<.001) and care setting decisions (51.4% vs 47.6%) (P<.005). Cost-sharing arrangements targeting patients are likely to have limited effects in safely reducing health care spending because physicians do not routinely consider patients' OP costs when making decisions regarding more expensive medical services.

[Nephro-urological monitoring technology based on radionuclide functional tests (tasks of an automated workplace)].

PubMed

Averinova, S G; Kashkadaeva, A V; Shiriaev, S V; Nechipaĭ, A M; Dmitrieva, G D

1999-01-01

The paper deals with a diagnostic informational and analytical system (DIAS). The system is based on the current concept of a dynamic model of nephro-urological clearance macroregulation under retention factors at the pre-, intra-, and postrenal levels during drug load tests. DIAS includes a package of dynamic renoscintigraphic techniques, as well as original software support. A system for parameters of renal clearance regulation has been developed, which is effective at nephro-urological screening and monitoring at all treatment stages for cancer patients. A two-detector chamber which permits the mounting of a detector at an angle to the patient's body is the optimum diagnostic apparatus for a cancer clinic. The use of functional tests makes it possible to examine the regulatory reserves for each kidney, followed up by the choice of adequate corrective measures to prevent renal failure during treatment. In some cases, DIAS monitoring frequently shows a higher sensitivity to the signs of latent renal failure than does routine clinical and laboratory monitoring. The effective radiation dose taken by a patient during a study by the DIAS technology aimed at reducing radioopaque doses is 100-150 times higher than that at an X-ray study and is an order less than during routine urinary tests.

THE HARD OF HEARING. PRENTICE-HALL FOUNDATIONS OF SPEECH PATHOLOGY SERIES.

ERIC Educational Resources Information Center

O'NEILL, JOHN J.

BASIC INFORMATION ABOUT TESTING, DIAGNOSING, AND REHABILITATING THE HARD OF HEARING IS OFFERED IN THIS INTRODUCTORY TEXT. THE PHYSICS OF SOUND, AUDITORY THEORY, ANATOMY AND PATHOLOGY OF THE EAR, AND DIAGNOSTIC ROUTINES ARE DISCUSSED. A CHAPTER ON AURAL REHABILITATION INCLUDES AN OVERVIEW OF LIPREADING AND AUDITORY TRAINING TECHNIQUES FOR ADULTS…

Value of routine investigations to predict loop diuretic down-titration success in stable heart failure.

PubMed

Martens, Pieter; Verbrugge, Frederik H; Boonen, Levinia; Nijst, Petra; Dupont, Matthias; Mullens, Wilfried

2018-01-01

Guidelines advocate down-titration of loop diuretics in chronic heart failure (CHF) when patients have no signs of volume overload. Limited data are available on the expected success rate of this practice or how routine diagnostic tests might help steering this process. Fifty ambulatory CHF-patients on stable neurohumoral blocker/diuretic therapy for at least 3months without any clinical sign of volume overload were prospectively included to undergo loop diuretic down-titration. All patients underwent a similar pre-down-titration evaluation consisting of a dyspnea scoring, physical examination, transthoracic echocardiography (diastolic function, right ventricular function, cardiac filling pressures and valvular disease), blood sample (serum creatinine, plasma NT-pro-BNP and neurohormones). Loop diuretic maintenance dose was subsequently reduced by 50% or stopped if dose was ≤40mg furosemide equivalents. Successful down-titration was defined as a persistent dose reduction after 30days without weight increase >1.5kg or new-onset symptoms of worsening heart failure. At 30-day follow-up, down-titration was successful in 62% (n=31). In 12/19 patients exhibiting down-titration failure, this occurred within the first week. Physical examination, transthoracic echocardiography and laboratory analysis had limited predictive capability to detect patients with down-titration success/failure (positive likelihood-ratios below 1.5, or area under the curve [AUC] non-statically different from AUC=0.5). Loop diuretic down-titration is feasible in a majority of stable CHF patients in which the treating clinician felt continuation of loops was unnecessary to sustain euvolemia. Importantly, routine diagnostics which suggest euvolemia, have limited diagnostic impact on the post-test probability. Copyright © 2017 Elsevier B.V. All rights reserved.

[Thalassaemia diagnostics].

PubMed

Kusters, Elske; Kerkhoffs, Jean-Louis H; van Rossum, André P

2014-01-01

The thalassaemias are characterised by quantitative aberrations in the production of the globin chains that make up haemoglobin, and are a subgroup of the haemoglobinopathies. In this LabQuiz we show how thalassaemia carrier status can be indicated in the results of regular laboratory tests, and discuss the laboratory diagnostics that can confirm or rule out thalassaemia. In these two cases we will present a man of Moroccan descent, and two brothers of Filipino descent, all with anaemia and microcytosis. We show it is possible to differentiate between iron-deficiency anaemia and thalassaemia carrier status on the basis of a complete blood count and measurement of ferritin levels, and which laboratory diagnostics can be subsequently performed in order to confirm a suspicion of thalassaemia. The background section discusses the properties and pitfalls of routine laboratory diagnostics for the thalassaemias, and thalassaemia diagnostics in the Dutch newborn screening programme.

Bootstrap-based procedures for inference in nonparametric receiver-operating characteristic curve regression analysis.

PubMed

Rodríguez-Álvarez, María Xosé; Roca-Pardiñas, Javier; Cadarso-Suárez, Carmen; Tahoces, Pablo G

2018-03-01

Prior to using a diagnostic test in a routine clinical setting, the rigorous evaluation of its diagnostic accuracy is essential. The receiver-operating characteristic curve is the measure of accuracy most widely used for continuous diagnostic tests. However, the possible impact of extra information about the patient (or even the environment) on diagnostic accuracy also needs to be assessed. In this paper, we focus on an estimator for the covariate-specific receiver-operating characteristic curve based on direct regression modelling and nonparametric smoothing techniques. This approach defines the class of generalised additive models for the receiver-operating characteristic curve. The main aim of the paper is to offer new inferential procedures for testing the effect of covariates on the conditional receiver-operating characteristic curve within the above-mentioned class. Specifically, two different bootstrap-based tests are suggested to check (a) the possible effect of continuous covariates on the receiver-operating characteristic curve and (b) the presence of factor-by-curve interaction terms. The validity of the proposed bootstrap-based procedures is supported by simulations. To facilitate the application of these new procedures in practice, an R-package, known as npROCRegression, is provided and briefly described. Finally, data derived from a computer-aided diagnostic system for the automatic detection of tumour masses in breast cancer is analysed.

Incorporating uncertainty into medical decision making: an approach to unexpected test results.

PubMed

Bianchi, Matt T; Alexander, Brian M; Cash, Sydney S

2009-01-01

The utility of diagnostic tests derives from the ability to translate the population concepts of sensitivity and specificity into information that will be useful for the individual patient: the predictive value of the result. As the array of available diagnostic testing broadens, there is a temptation to de-emphasize history and physical findings and defer to the objective rigor of technology. However, diagnostic test interpretation is not always straightforward. One significant barrier to routine use of probability-based test interpretation is the uncertainty inherent in pretest probability estimation, the critical first step of Bayesian reasoning. The context in which this uncertainty presents the greatest challenge is when test results oppose clinical judgment. It is this situation when decision support would be most helpful. The authors propose a simple graphical approach that incorporates uncertainty in pretest probability and has specific application to the interpretation of unexpected results. This method quantitatively demonstrates how uncertainty in disease probability may be amplified when test results are unexpected (opposing clinical judgment), even for tests with high sensitivity and specificity. The authors provide a simple nomogram for determining whether an unexpected test result suggests that one should "switch diagnostic sides.'' This graphical framework overcomes the limitation of pretest probability uncertainty in Bayesian analysis and guides decision making when it is most challenging: interpretation of unexpected test results.

Naked-eye fingerprinting of single nucleotide polymorphisms on psoriasis patients

NASA Astrophysics Data System (ADS)

Valentini, Paola; Marsella, Alessandra; Tarantino, Paolo; Mauro, Salvatore; Baglietto, Silvia; Congedo, Maurizio; Paolo Pompa, Pier

2016-05-01

We report a low-cost test, based on gold nanoparticles, for the colorimetric (naked-eye) fingerprinting of a panel of single nucleotide polymorphisms (SNPs), relevant for the personalized therapy of psoriasis. Such pharmacogenomic tests are not routinely performed on psoriasis patients, due to the high cost of standard technologies. We demonstrated high sensitivity and specificity of our colorimetric test by validating it on a cohort of 30 patients, through a double-blind comparison with two state-of-the-art instrumental techniques, namely reverse dot blotting and sequencing, finding 100% agreement. This test offers high parallelization capabilities and can be easily generalized to other SNPs of clinical relevance, finding broad utility in diagnostics and pharmacogenomics.We report a low-cost test, based on gold nanoparticles, for the colorimetric (naked-eye) fingerprinting of a panel of single nucleotide polymorphisms (SNPs), relevant for the personalized therapy of psoriasis. Such pharmacogenomic tests are not routinely performed on psoriasis patients, due to the high cost of standard technologies. We demonstrated high sensitivity and specificity of our colorimetric test by validating it on a cohort of 30 patients, through a double-blind comparison with two state-of-the-art instrumental techniques, namely reverse dot blotting and sequencing, finding 100% agreement. This test offers high parallelization capabilities and can be easily generalized to other SNPs of clinical relevance, finding broad utility in diagnostics and pharmacogenomics. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr02200f

Screening for ALK in non-small cell lung carcinomas: 5A4 and D5F3 antibodies perform equally well, but combined use with FISH is recommended.

PubMed

Savic, Spasenija; Diebold, Joachim; Zimmermann, Anne-Katrin; Jochum, Wolfram; Baschiera, Betty; Grieshaber, Susanne; Tornillo, Luigi; Bisig, Bettina; Kerr, Keith; Bubendorf, Lukas

2015-08-01

Immunohistochemistry (IHC) has become a promising method for pre-screening ALK-rearrangements in non-small cell lung carcinomas (NSCLC). Various ALK antibodies, detection systems and automated immunostainers are available. We therefore aimed to compare the performance of the monoclonal 5A4 (Novocastra, Leica) and D5F3 (Cell Signaling, Ventana) antibodies using two different immunostainers. Additionally we analyzed the accuracy of prospective ALK IHC-testing in routine diagnostics. Seventy-two NSCLC with available ALK FISH results and enriched for FISH-positive carcinomas were retrospectively analyzed. IHC was performed on BenchMarkXT (Ventana) using 5A4 and D5F3, respectively, and additionally with 5A4 on Bond-MAX (Leica). Data from our routine diagnostics on prospective ALK-testing with parallel IHC, using 5A4, and FISH were available from 303 NSCLC. All three IHC protocols showed congruent results. Only 1/25 FISH-positive NSCLC (4%) was false negative by IHC. For all three IHC protocols the sensitivity, specificity, positive (PPV) and negative predictive values (NPV) compared to FISH were 96%, 100%, 100% and 97.8%, respectively. In the prospective cohort 3/32 FISH-positive (9.4%) and 2/271 FISH-negative (0.7%) NSCLC were false negative and false positive by IHC, respectively. In routine diagnostics the sensitivity, specificity, PPV and NPV of IHC compared to FISH were 90.6%, 99.3%, 93.5% and 98.9%, respectively. 5A4 and D5F3 are equally well suited for detecting ALK-rearranged NSCLC. BenchMark and BOND-MAX immunostainers can be used for IHC with 5A4. True discrepancies between IHC and FISH results do exist and need to be addressed when implementing IHC in an ALK-testing algorithm. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Lyssaviruses: special emphasis on rabies virus and other members of the lyssavirus genus.

PubMed

Harkess, Graeme; Fooks, Anthony R

2011-01-01

Rabies is routinely diagnosed based on the clinical description and history of exposure in a rabies-endemic country. A negative diagnostic test for rabies virus or a related lyssavirus does not exclude the clinical diagnosis. Diagnostic tests are never optimal and are entirely dependent on the nature and quality of the sample supplied. Often, only a sample from a single time point is investigated reducing the overall sensitivity of any diagnosis. With the advent of molecular biology, tests have been developed that are rapid, robust, and sensitive in support of the rapid detection and strain identification of rabies virus from clinical specimens. These molecular tests complement conventional tests in rabies diagnosis, particularly for human cases, for which an early laboratory diagnosis is critical and may decrease the number of unnecessary contacts with the patient, reduce the requirement for invasive and costly interventions, and enable the appropriate medical treatment regimen to be administered for the patient. The barrier to success is in transferring the technology for the latest techniques in rabies diagnosis to rabies-endemic countries. These barriers are not insurmountable and in liaison with international organisations, especially OIE, FAO, and WHO, these diagnostic tests will be validated for rabies diagnosis and surveillance, and implemented in modern and well-equipped diagnostic laboratories throughout the world.

Aminopenicillin-associated exanthem: lymphocyte transformation testing revisited.

PubMed

Trautmann, A; Seitz, C S; Stoevesandt, J; Kerstan, A

2014-12-01

The lymphocyte transformation test (LTT) has been promoted as in-vitro test for diagnosis of drug hypersensitivity. For determination of statistical LTT sensitivity, series of patients with clinically uniform reactions followed by complete drug hypersensitivity work-up are mandatory. Assessment of LTT specificity requires control patients who tolerated exposure to the drug studied. To prospectively determine the diagnostic value of the LTT in a clinically and diagnostically well-defined series of patients. Patients with exanthematous skin eruptions after ampicillin (AMP) intake were included in this study. After exclusion or confirmation of delayed-onset allergic AMP hypersensitivity by skin and provocation testing, two independent LTTs were performed: one standard LTT and a modified LTT with additional anti-CD3/anti-CD28 monoclonal antibody stimulation. By testing, delayed-onset allergic AMP hypersensitivity was diagnosed in 11 patients and definitely ruled out in 26. The standard LTT reached a diagnostic sensitivity of 54.5% while the modified LTT yielded 72.7%. However, the methodical test modification resulted in a decline of specificity from 92.3% (standard LTT) to 76.9%. In cases of AMP-associated exanthems, the diagnostic value of the LTT compared with routine allergy testing is limited. When evaluating such exanthems, provocation testing remains the gold standard. Delayed reading of intradermal skin tests remains most useful to avoid positive provocation reactions. © 2014 John Wiley & Sons Ltd.

Adding video recording increases the diagnostic yield of routine electroencephalograms in children with frequent paroxysmal events.

PubMed

Watemberg, Nathan; Tziperman, Barak; Dabby, Ron; Hasan, Mariana; Zehavi, Liora; Lerman-Sagie, Tally

2005-05-01

To report on the usefulness of adding video recording to routine EEG studies of infants and children with frequent paroxysmal events. We analyzed the efficacy of this diagnostic means during a 4-year period. The decision whether to add video recording was made by the pediatric EEG interpreter at the time of the study. Studies were planned to last between 20 and 30 min, and, if needed, were extended by the EEG interpreter. For most studies, video recording was added from the beginning of EEG recording. In a minority of cases, the addition of video was implemented during the first part of the EEG test, as clinical events became obvious. In these cases, a new study (file) was begun. The success rate was analyzed according to the indications for the EEG study: paroxysmal eye movements, tremor, suspected seizures, myoclonus, staring episodes, suspected stereotypias and tics, absence epilepsy follow-up, cyanotic episodes, and suspected psychogenic nonepileptic events. Video recording was added to 137 of 666 routine studies. Mean patient age was 4.8 years. The nature of the event was determined in 61 (45%) of the EEG studies. Twenty-eight percent were hospitalized patients. The average study duration was 26 min. This diagnostic means was particularly useful for paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and psychogenic nonepileptic events. About 46% of 116 patients for whom cognitive data were available were mentally retarded. EEG with added video recording was successfully performed in all 116 cases and provided useful information in 29 (55%) of these 53 patients. Adding video recording to routine EEG was helpful in 45% of cases referred for frequent paroxysmal events. This technique proved useful for hospitalized children as well as for outpatients. Moreover, it was successfully applied in cognitively impaired patients. Infants and children with paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and pseudoseizures especially benefited from this diagnostic means. Because of its low cost and the little discomfort imposed on the patient and his or her family, this technique should be considered as a first diagnostic step in children with frequent paroxysmal events.

Molecular and Nonmolecular Diagnostic Methods for Invasive Fungal Infections

PubMed Central

Arvanitis, Marios; Anagnostou, Theodora; Fuchs, Beth Burgwyn; Caliendo, Angela M.

2014-01-01

SUMMARY Invasive fungal infections constitute a serious threat to an ever-growing population of immunocompromised individuals and other individuals at risk. Traditional diagnostic methods, such as histopathology and culture, which are still considered the gold standards, have low sensitivity, which underscores the need for the development of new means of detecting fungal infectious agents. Indeed, novel serologic and molecular techniques have been developed and are currently under clinical evaluation. Tests like the galactomannan antigen test for aspergillosis and the β-glucan test for invasive Candida spp. and molds, as well as other antigen and antibody tests, for Cryptococcus spp., Pneumocystis spp., and dimorphic fungi, have already been established as important diagnostic approaches and are implemented in routine clinical practice. On the other hand, PCR and other molecular approaches, such as matrix-assisted laser desorption ionization (MALDI) and fluorescence in situ hybridization (FISH), have proved promising in clinical trials but still need to undergo standardization before their clinical use can become widespread. The purpose of this review is to highlight the different diagnostic approaches that are currently utilized or under development for invasive fungal infections and to identify their performance characteristics and the challenges associated with their use. PMID:24982319

Diagnostic accuracy of tuberculous lymphadenitis fine needle aspiration biopsy confirmed by PCR as gold standard

NASA Astrophysics Data System (ADS)

DSuryadi; Delyuzar; Soekimin

2018-03-01

Indonesia is the second country with the TB (tuberculosis) burden in the world. Improvement in controlling TB and reducing the complications can accelerate early diagnosis and correct treatment. PCR test is a gold standard. However, it is quite expensive for routine diagnosis. Therefore, an accurate and cheaper diagnostic method such as fine needle aspiration biopsy is needed. The study aimsto determine the accuracy of fine needle aspiration biopsy cytology in the diagnosis of tuberculous lymphadenitis. A cross-sectional analytic study was conducted to the samples from patients suspected with tuberculous lymphadenitis. The fine needle aspiration biopsy (FNAB)test was performed and confirmed by PCR test.There is a comparison to the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of both methods. Sensitivity (92.50%), specificity (96.49%), accuracy (94.85%), positive predictive value (94.87%) and negative predictive value (94.83%) were in FNAB test compared to gold standard. We concluded that fine needle aspiration biopsy is a recommendation for a cheaper and accurate diagnostic test for tuberculous lymphadenitis diagnosis.

"Combined Diagnostic Tool" APPlication to a Retrospective Series of Patients Undergoing Total Joint Revision Surgery.

PubMed

Gallazzi, Enrico; Drago, Lorenzo; Baldini, Andrea; Stockley, Ian; George, David A; Scarponi, Sara; Romanò, Carlo L

2017-01-01

Background : Differentiating between septic and aseptic joint prosthesis may be challenging, since no single test is able to confirm or rule out infection. The choice and interpretation of the panel of tests performed in any case often relies on empirical evaluation and poorly validated scores. The "Combined Diagnostic Tool (CDT)" App, a smartphone application for iOS, was developed to allow to automatically calculate the probability of having a of periprosthetic joint infection, on the basis of the relative sensitivity and specificity of the positive and negative diagnostic tests performed in any given patient. Objective : The aim of the present study was to apply the CDT software to investigate the ability of the tests routinely performed in three high-volume European centers to diagnose a periprosthetic infection. Methods : This three-center retrospective study included 120 consecutive patients undergoing total hip or knee revision, and included 65 infected patients (Group A) and 55 patients without infection (Group B). The following parameters were evaluated: number and type of positive and negative diagnostic tests performed pre-, intra- and post-operatively and resultant probability calculated by the CDT App of having a peri-prosthetic joint infection, based on pre-, intra- and post-operative combined tests. Results : Serological tests were the most common performed, with an average 2.7 tests per patient for Group A and 2.2 for Group B, followed by joint aspiration (0.9 and 0.8 tests per patient, respectively) and imaging techniques (0.5 and 0.2 test per patient). Mean CDT App calculated probability of having an infection based on pre-operative tests was 79.4% for patients in Group A and 35.7 in Group B. Twenty-nine patients in Group A had > 10% chance of not having an infection, and 29 of Group B had > 10% chance of having an infection. Conclusion : This is the first retrospective study focused on investigating the number and type of tests commonly performed prior to joint revision surgery and aimed at evaluating their combined ability to diagnose a peri-prosthetic infection. CDT App allowed us to demonstrate that, on average, the routine combination of commonly used tests is unable to diagnose pre-operatively a peri-prosthetic infection with a probability higher than 90%.

[Serological diagnosis of whooping cough using immunoblot methods].

PubMed

Lochman, I; Pokorná, L; Mertová, H

2017-01-01

The aim of this study was to challenge the conclusion presented in the current recommendations of the EU Perstrain Group (European group of reference laboratories) [17] that immunoblotting methods are not appropriate serological methods for the diagnosis of pertussis because their results cannot be quantified. To consider benefits of these methods for the diagnosis of Bordetella infections was another aim of this work. The residual sera from routine testing intended for disposal and results of routine tests for Bordetella infections performed in Spadia Lab in 2015 and 2016 were used in this study. The test samples were anonymized. Standard commercial ELISA and immunoblot kits were used for analyses. Using the TestLine Clinical Diagnostics Company kits, we have shown that, contrary to the conclusion of the EU Perstrain Group, quantification of the immunoblot results is possible and that these methods can improve the diagnosis of Bordetella infections, ultimately making it more effective.

High diagnostic yield by CSF-PCR for entero- and herpes simplex viruses and TBEV serology in adults with acute aseptic meningitis in Stockholm.

PubMed

Franzen-Rohl, Elisabeth; Larsson, Kenny; Skoog, Eva; Tiveljung-Lindell, Annika; Grillner, Lena; Aurelius, Elisabeth; Glimåker, Martin

2008-01-01

Acute aseptic meningitis (AAM) affects 10-20/100,000 inhabitants per years in Sweden. Up to the beginning of the 1980s the diagnoses were made by virus isolation and/or determination of viral antibodies in serum. The development of PCR for detection of viruses in CSF samples has increased the sensitivity and diagnostic efficiency considerably. We investigated the aetiology of AAM and the diagnostic efficiency in an adult population in Stockholm, using a limited first-line combination of microbiological assays. CSF and serum samples, consecutively collected in 419 patients with clinical symptoms of AAM in northern Stockholm during 1999-2004, were included. PCR assays for herpes simplex virus (HSV) DNA and enterovirus (EV) RNA in the CSF as well as ELISA for IgM in serum to tick-borne encephalitis virus (TBEV) were performed routinely. A viral diagnosis was obtained in 255 of the 419 cases (62%) with these routinely performed assays. Clinical findings in combination with additional diagnostic tests resulted in an overall aetiological yield of 72%. EV was the major causative agent (27%) followed by TBEV (21%) and HSV-2 (19%). We conclude that consistent use of CSF-PCR for EV and HSV and TBEV serology established a diagnosis in the majority of AAM patients.

[Video-Head impulse test with little diagnostic impact in vertigo-patients].

PubMed

Patscheke, Jochen Henrik; Plenz, Pauline; Ernst, Stephan; Klußmann, Jens-Peter

2018-03-01

Video-head impulse test (V-HIT) is more and more becoming a routine test in patients with vertigo, contributing information about the vestibulo-ocular reflex (VOR). According to Ewald's second law, the unilateral pathological test points to this side's peripheral organ as being diseased. The value in clinical routine is still unclear. 171 consecutive patients with vertigo that had received a V-HIT and caloric testing at presentation in an academic ENT-department were included. By chart-review, they were categorized in different groups with unilateral peripheral, central and other etiology of vertigo, irrespective of their V-HIT result. Then the latter was analyzed within the different groups with respect to Gain, Gain-Asymmetry (GA) and Catch-up Saccades (CS). Canal Paresis (CP) from caloric testing was compared to GA. In patients with unilateral peripheral disease, 31 % showed a pathological gain (< 0.8), the mean GA was 4.53 % (± 16.72 %) and 60 % had CSs. In patients with presumed or assured central etiology, these data were 28 %, -1,56 % (± 17,89 %) and 45 %. Isolated CS occurred only sporadically. CP was not correlated with GA in all groups (p = 0,114). In this study V-HIT showed little diagnostic use, especially in separating peripheral from central disease. The lacking correlation between asymmetry in caloric testing and asymmetry of V-HIT gain challenges current pathophysiological concepts of impaired VOR. Georg Thieme Verlag KG Stuttgart · New York.

Molecular tissue changes in early myocardial ischemia: from pathophysiology to the identification of new diagnostic markers.

PubMed

Aljakna, Aleksandra; Fracasso, Tony; Sabatasso, Sara

2018-03-01

Diagnosing early myocardial ischemia (the initial 4 to 6 h after interruption of blood flow to part of the myocardium) remains a challenge for clinical and forensic pathologists. Several immunohistochemical markers have been proposed for improving postmortem detection of early myocardial ischemia; however, no single marker appears to be both sufficiently specific as well as sensitive. This review summarizes the diverse categories of molecular tissue markers that have been investigated in human autopsy samples with acute myocardial infarction as well as in the well-established and widely used in vivo animal model of early myocardial ischemia (permanent ligation of the coronary artery). Recently identified markers appearing during the initial 2 h of myocardial ischemia are highlighted. Among them, only six were tested for specificity (C5b-9, hypoxia-inducible factor 1-alpha, vascular endothelial growth factor, heart fatty acid binding protein, connexin 43, and JunB). Despite the discovery of several potentially promising markers (in terms of early expression and specificity), many of them remain to be tested and validated for application in routine diagnostics in clinical and forensic pathology. In particular, research investigating the postmortem stability of these markers is required before any might be implemented into routine diagnostics. Establishing a standardized panel of immunohistochemical markers may be more useful for improving sensitivity and specificity than searching for a single marker.

Methods in virus diagnostics: from ELISA to next generation sequencing.

PubMed

Boonham, Neil; Kreuze, Jan; Winter, Stephan; van der Vlugt, René; Bergervoet, Jan; Tomlinson, Jenny; Mumford, Rick

2014-06-24

Despite the seemingly continuous development of newer and ever more elaborate methods for detecting and identifying viruses, very few of these new methods get adopted for routine use in testing laboratories, often despite the many and varied claimed advantages they possess. To understand why the rate of uptake of new technologies is so low, requires a strong understanding of what makes a good routine diagnostic tool to begin. This can be done by looking at the two most successfully established plant virus detection methods: enzyme-linked immunosorbant assay (ELISA) and more recently introduced real-time polymerase chain reaction (PCR). By examining the characteristics of this pair of technologies, it becomes clear that they share many benefits, such as an industry standard format and high levels of repeatability and reproducibility. These combine to make methods that are accessible to testing labs, which are easy to establish and robust in their use, even with new and inexperienced users. Hence, to ensure the establishment of new techniques it is necessary to not only provide benefits not found with ELISA or real-time PCR, but also to provide a platform that is easy to establish and use. In plant virus diagnostics, recent developments can be clustered into three core areas: (1) techniques that can be performed in the field or resource poor locations (e.g., loop-mediated isothermal amplification LAMP); (2) multiplex methods that are able to detect many viruses in a single test (e.g., Luminex bead arrays); and (3) methods suited to virus discovery (e.g., next generation sequencing, NGS). Field based methods are not new, with Lateral Flow Devices (LFDs) for the detection being available for a number of years now. However, the widespread uptake of this technology remains poor. LAMP does offer significant advantages over LFDs, in terms of sensitivity and generic application, but still faces challenges in terms of establishment. It is likely that the main barrier to the uptake of field-based technologies is behavioural influences, rather than specific concerns about the performance of the technologies themselves. To overcome this, a new relationship will need to develop between centralised testing laboratories offering services and those requiring tests; a relationship which is currently in its infancy. Looking further into the future, virus discovery and multiplex methods seem to converge as NGS becomes ever cheaper, easier to perform and can provide high levels of multiplexing without the use of virus specific reagents. So ultimately the key challenge from a routine testing lab perspective will not be one of investment in platforms-which could even be outsourced to commercial sequencing services-but one of having the skills and expertise to analyse the large datasets generated and their subsequent interpretation. In conclusion, only time will tell which of the next-generation of methods currently in development will become the routine diagnostics of the future. This will be determined through a combination of factors. And while the technology itself will have to offer performance advantages over existing methods in order to supplant them, it is likely to be human factors e.g., the behaviours of end users, laboratories and policy makers, the availability of appropriate expertise, that ultimately determine which ones become established. Hence factors cannot be ignored and early engagement with diagnostic stakeholders is essential. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Current status and future perspectives on molecular and serological methods in diagnostic mycology.

PubMed

Lau, Anna; Chen, Sharon; Sleiman, Sue; Sorrell, Tania

2009-11-01

Invasive fungal infections are an important cause of infectious morbidity. Nonculture-based methods are increasingly used for rapid, accurate diagnosis to improve patient outcomes. New and existing DNA amplification platforms have high sensitivity and specificity for direct detection and identification of fungi in clinical specimens. Since laboratories are increasingly reliant on DNA sequencing for fungal identification, measures to improve sequence interpretation should support validation of reference isolates and quality control in public gene repositories. Novel technologies (e.g., isothermal and PNA FISH methods), platforms enabling high-throughput analyses (e.g., DNA microarrays and Luminex xMAP) and/or commercial PCR assays warrant further evaluation for routine diagnostic use. Notwithstanding the advantages of molecular tests, serological assays remain clinically useful for patient management. The serum Aspergillus galactomannan test has been incorporated into diagnostic algorithms of invasive aspergillosis. Both the galactomannan and the serum beta-D-glucan test have value for diagnosing infection and monitoring therapeutic response.

Inconsistent Results of Diagnostic Tools Hamper the Differentiation between Bee and Vespid Venom Allergy

PubMed Central

Sturm, Gunter J.; Jin, Chunsheng; Kranzelbinder, Bettina; Hemmer, Wolfgang; Sturm, Eva M.; Griesbacher, Antonia; Heinemann, Akos; Vollmann, Jutta; Altmann, Friedrich; Crailsheim, Karl; Focke, Margarete; Aberer, Werner

2011-01-01

Background Double sensitization (DS) to bee and vespid venom is frequently observed in the diagnosis of hymenoptera venom allergy, but clinically relevant DS is rare. Therefore it is sophisticated to choose the relevant venom for specific immunotherapy and overtreatment with both venoms may occur. We aimed to compare currently available routine diagnostic tests as well as experimental tests to identify the most accurate diagnostic tool. Methods 117 patients with a history of a bee or vespid allergy were included in the study. Initially, IgE determination by the ImmunoCAP, by the Immulite, and by the ADVIA Centaur, as well as the intradermal test (IDT) and the basophil activation test (BAT) were performed. In 72 CAP double positive patients, individual IgE patterns were determined by western blot inhibition and component resolved diagnosis (CRD) with rApi m 1, nVes v 1, and nVes v 5. Results Among 117 patients, DS was observed in 63.7% by the Immulite, in 61.5% by the CAP, in 47.9% by the IDT, in 20.5% by the ADVIA, and in 17.1% by the BAT. In CAP double positive patients, western blot inhibition revealed CCD-based DS in 50.8%, and the CRD showed 41.7% of patients with true DS. Generally, agreement between the tests was only fair and inconsistent results were common. Conclusion BAT, CRD, and ADVIA showed a low rate of DS. However, the rate of DS is higher than expected by personal history, indicating that the matter of clinical relevance is still not solved even by novel tests. Furthermore, the lack of agreement between these tests makes it difficult to distinguish between bee and vespid venom allergy. At present, no routinely employed test can be regarded as gold standard to find the clinically relevant sensitization. PMID:21698247

The impact of commercial rapid respiratory virus diagnostic tests on patient outcomes and health system utilization.

PubMed

Ko, Fiona; Drews, Steven J

2017-10-01

Acute respiratory tract infections due to influenza A/B and respiratory syncytial virus (RSV) are major causes of morbidity and mortality globally. Rapid tests for detection of these pathogens include antigen detection point of care tests (POC) and newer easy to use molecular tests. From experience, these assays improve both laboratory workflow and assay interpretation issues. However, the question of the benefits of using rapid test technology compared to routine laboratory testing for respiratory viral pathogens is still often asked. Areas covered: Specifically, this review aims to; 1) identify clinical/patient indicators that can be measured prior to and following the implementation of rapid diagnostic test for influenza and RSV, 2) provide multiple perspectives on the extent of impact of a rapid diagnostic test, including direct and indirect outcomes, and 3) identify the technological advancements in the development of rapid testing, demonstrating a timeline that transitions from antigen-based assays to molecular assays. Expert commentary: Key benefits to the use of either antigen-based or molecular rapid tests for patient care, patient flow within institutions, as well as laboratory utilization are identified. Due to improved test characteristics, the authors feel that rapid molecular tests have greater benefits than antigen-based detection methods.

Monitoring and investigating natural disease by veterinary pathologists in diagnostic laboratories.

PubMed

O'Toole, D

2010-01-01

Many emerging diseases in animals are initially recognized by diagnostic pathologists in animal health laboratories using routine laboratory submissions, in conjunction with clinical veterinarians and wildlife biologists. Familiar recent examples are chronic wasting disease, bovine spongiform encephalopathy, West Nile encephalomyelitis in North America, and postweaning multisystemic wasting syndrome in pigs. The recognition of new diseases in animals requires that the curiosity of diagnosticians be articulated with the capacity of animal health laboratories to create effective diagnostic teams, solicit additional cases from the field at minimal cost to clients, and develop relationships with basic researchers. Bovine neosporosis is used as an example to illustrate how a disease investigation triggered by routine clinical accessions can have international ramifications. Between the late 1980s and 1995, diagnosticians with California's animal health laboratory system identified neosporosis as a cause of reproductive wastage in cattle, characterized the lesions, isolated the agent, defined routes of transmission, met Koch's postulates, and developed diagnostic assays. Diagnostic pathologists catalyzed the process. The neosporosis investigation in California suggests useful attributes of veterinary diagnostic laboratories that pursue emerging diseases identified through routine laboratory accessions.

High-resolution chromosomal microarrays in prenatal diagnosis significantly increase diagnostic power.

PubMed

Oneda, Beatrice; Baldinger, Rosa; Reissmann, Regina; Reshetnikova, Irina; Krejci, Pavel; Masood, Rahim; Ochsenbein-Kölble, Nicole; Bartholdi, Deborah; Steindl, Katharina; Morotti, Denise; Faranda, Marzia; Baumer, Alessandra; Asadollahi, Reza; Joset, Pascal; Niedrist, Dunja; Breymann, Christian; Hebisch, Gundula; Hüsler, Margaret; Mueller, René; Prentl, Elke; Wisser, Josef; Zimmermann, Roland; Rauch, Anita

2014-06-01

The objective of this study was to determine for the first time the reliability and the diagnostic power of high-resolution microarray testing in routine prenatal diagnostics. We applied high-resolution chromosomal microarray testing in 464 cytogenetically normal prenatal samples with any indication for invasive testing. High-resolution testing revealed a diagnostic yield of 6.9% and 1.6% in cases of fetal ultrasound anomalies and cases of advanced maternal age (AMA), respectively, which is similar to previous studies using low-resolution microarrays. In three (0.6%) additional cases with an indication of AMA, an aberration in susceptibility risk loci was detected. Moreover, one case (0.2%) showed an X-linked aberration in a female fetus, a finding relevant for future family planning. We found the rate of cases, in which the parents had to be tested for interpretation of unreported copy number variants (3.7%), and the rate of remaining variants of unknown significance (0.4%) acceptably low. Of note, these findings did not cause termination of pregnancy after expert genetic counseling. The 0.4% rate of confined placental mosaicism was similar to that observed by conventional karyotyping and notably involved a case of placental microdeletion. High-resolution prenatal microarray testing is a reliable technique that increases diagnostic yield by at least 17.3% when compared with conventional karyotyping, without an increase in the frequency of variants of uncertain significance. © 2014 John Wiley & Sons, Ltd.

Support for Diagnosis of Custom Computer Hardware

NASA Technical Reports Server (NTRS)

Molock, Dwaine S.

2008-01-01

The Coldfire SDN Diagnostics software is a flexible means of exercising, testing, and debugging custom computer hardware. The software is a set of routines that, collectively, serve as a common software interface through which one can gain access to various parts of the hardware under test and/or cause the hardware to perform various functions. The routines can be used to construct tests to exercise, and verify the operation of, various processors and hardware interfaces. More specifically, the software can be used to gain access to memory, to execute timer delays, to configure interrupts, and configure processor cache, floating-point, and direct-memory-access units. The software is designed to be used on diverse NASA projects, and can be customized for use with different processors and interfaces. The routines are supported, regardless of the architecture of a processor that one seeks to diagnose. The present version of the software is configured for Coldfire processors on the Subsystem Data Node processor boards of the Solar Dynamics Observatory. There is also support for the software with respect to Mongoose V, RAD750, and PPC405 processors or their equivalents.

Robust detection of EGFR copy number changes and EGFR variant III: technical aspects and relevance for glioma diagnostics.

PubMed

Jeuken, Judith; Sijben, Angelique; Alenda, Cristina; Rijntjes, Jos; Dekkers, Marieke; Boots-Sprenger, Sandra; McLendon, Roger; Wesseling, Pieter

2009-10-01

Epidermal growth factor receptor (EGFR) is commonly affected in cancer, generally in the form of an increase in DNA copy number and/or as mutation variants [e.g., EGFR variant III (EGFRvIII), an in-frame deletion of exons 2-7]. While detection of EGFR aberrations can be expected to be relevant for glioma patients, such analysis has not yet been implemented in a routine setting, also because feasible and robust assays were lacking. We evaluated multiplex ligation-dependent probe amplification (MLPA) for detection of EGFR amplification and EGFRvIII in DNA of a spectrum of 216 diffuse gliomas. EGFRvIII detection was verified at the protein level by immunohistochemistry and at the RNA level using the conventionally used endpoint RT-PCR as well as a newly developed quantitative RT-PCR. Compared to these techniques, the DNA-based MLPA assay for EGFR/EGFRvIII analysis tested showed 100% sensitivity and specificity. We conclude that MLPA is a robust assay for detection of EGFR/EGFRvIII aberrations. While the exact diagnostic, prognostic and predictive value of such EGFR testing remains to be seen, MLPA has great potential as it can reliably and relatively easily be performed on routinely processed (formalin-fixed, paraffin-embedded) tumor tissue in combination with testing for other relevant glioma markers.

A new SPECT/CT reconstruction algorithm: reliability and accuracy in clinical routine for non-oncologic bone diseases.

PubMed

Delcroix, Olivier; Robin, Philippe; Gouillou, Maelenn; Le Duc-Pennec, Alexandra; Alavi, Zarrin; Le Roux, Pierre-Yves; Abgral, Ronan; Salaun, Pierre-Yves; Bourhis, David; Querellou, Solène

2018-02-12

xSPECT Bone® (xB) is a new reconstruction algorithm developed by Siemens® in bone hybrid imaging (SPECT/CT). A CT-based tissue segmentation is incorporated into SPECT reconstruction to provide SPECT images with bone anatomy appearance. The objectives of this study were to assess xB/CT reconstruction diagnostic reliability and accuracy in comparison with Flash 3D® (F3D)/CT in clinical routine. Two hundred thirteen consecutive patients referred to the Brest Nuclear Medicine Department for non-oncological bone diseases were evaluated retrospectively. Two hundred seven SPECT/CT were included. All SPECT/CT were independently interpreted by two nuclear medicine physicians (a junior and a senior expert) with xB/CT then with F3D/CT three months later. Inter-observer agreement (IOA) and diagnostic confidence were determined using McNemar test, and unweighted Kappa coefficient. The study objectives were then re-assessed for validation through > 18 months of clinical and paraclinical follow-up. No statistically significant differences between IOA xB and IOA F3D were found (p = 0.532). Agreement for xB after categorical classification of the diagnoses was high (κ xB = 0.89 [95% CI 0.84 -0.93]) but without statistically significant difference F3D (κ F3D = 0.90 [95% CI 0.86 - 0.94]). Thirty-one (14.9%) inter-reconstruction diagnostic discrepancies were observed of which 21 (10.1%) were classified as major. The follow-up confirmed the diagnosis of F3D in 10 cases, xB in 6 cases and was non-contributory in 5 cases. xB reconstruction algorithm was found reliable, providing high interobserver agreement and similar diagnostic confidence to F3D reconstruction in clinical routine.

Laboratory testing for cytomegalovirus among pregnant women in the United States: a retrospective study using administrative claims data

PubMed Central

2012-01-01

Background Routine cytomegalovirus (CMV) screening during pregnancy is not recommended in the United States and the extent to which it is performed is unknown. Using a medical claims database, we computed rates of CMV-specific testing among pregnant women. Methods We used medical claims from the 2009 Truven Health MarketScan® Commercial databases. We computed CMV-specific testing rates using CPT codes. Results We identified 77,773 pregnant women, of whom 1,668 (2%) had a claim for CMV-specific testing. CMV-specific testing was significantly associated with older age, Northeast or urban residence, and a diagnostic code for mononucleosis. We identified 44 women with a diagnostic code for mononucleosis, of whom 14% had CMV-specific testing. Conclusions Few pregnant women had CMV-specific testing, suggesting that screening for CMV infection during pregnancy is not commonly performed. In the absence of national surveillance for CMV infections during pregnancy, healthcare claims are a potential source for monitoring practices of CMV-specific testing. PMID:23198949

Clinical review: Distinguishing constitutional delay of growth and puberty from isolated hypogonadotropic hypogonadism: critical appraisal of available diagnostic tests.

PubMed

Harrington, Jennifer; Palmert, Mark R

2012-09-01

Determining the etiology of delayed puberty during initial evaluation can be challenging. Specifically, clinicians often cannot distinguish constitutional delay of growth and puberty (CDGP) from isolated hypogonadotropic hypogonadism (IHH), with definitive diagnosis of IHH awaiting lack of spontaneous puberty by age 18 yr. However, the ability to make a timely, correct diagnosis has important clinical implications. The aim was to describe and evaluate the literature regarding the ability of diagnostic tests to distinguish CDGP from IHH. A PubMed search was performed using key words "puberty, delayed" and "hypogonadotropic hypogonadism," and citations within retrieved articles were reviewed to identify studies that assessed the utility of basal and stimulation tests in the diagnosis of delayed puberty. Emphasis was given to a test's ability to distinguish prepubertal adolescents with CDGP from those with IHH. Basal gonadotropin and GnRH stimulation tests have limited diagnostic specificity, with overlap in gonadotropin levels between adolescents with CDGP and IHH. Stimulation tests using more potent GnRH agonists and/or human chorionic gonadotropin may have better discriminatory value, but small study size, lack of replication of diagnostic thresholds, and prolonged protocols limit clinical application. A single inhibin B level in two recent studies demonstrated good differentiation between groups. Distinguishing IHH from CDGP is an important clinical issue. Basal inhibin B may offer a simple, discriminatory test if results from recent studies are replicated. However, current literature does not allow for recommendation of any diagnostic test for routine clinical use, making this an important area for future investigation.

Routine pharmacogenetic testing in clinical practice: dream or reality?

PubMed

Grossman, Iris

2007-10-01

Pharmacogenetics (PGx) has become progressively popular in recent years, thanks to growing anticipation among scientists, healthcare providers and the general public for the incorporation of genetic tests into the diagnostic arsenal at the physician's disposal. Indeed, much research has been dedicated to elucidation of genetic determinants underlying interindividual variability in pharmacokinetic parameters, as well as drug safety and efficacy. However, few PGx applications have thus far been realized in healthcare management. This review uses examples from PGx research of psychiatric drugs to illustrate why the current published findings are inadequate and insufficient for utilization as routine clinical predictors of treatment safety, efficacy or dosing. I therefore suggest the necessary steps to demonstrate the validity, utility and cost-effectiveness of PGx. These recommendations include a whole range of aspects, starting from standardization of criteria and assessment of the technical quality of genotyping assays, up to design of prospective PGx studies, providing the basis for reimbursement programs to be recognized in routine clinical practice.

Array-Based Comparative Genomic Hybridization for the Genomewide Detection of Submicroscopic Chromosomal Abnormalities

PubMed Central

Vissers, Lisenka E. L. M. ; de Vries, Bert B. A. ; Osoegawa, Kazutoyo ; Janssen, Irene M. ; Feuth, Ton ; Choy, Chik On ; Straatman, Huub ; van der Vliet, Walter ; Huys, Erik H. L. P. G. ; van Rijk, Anke ; Smeets, Dominique ; van Ravenswaaij-Arts, Conny M. A. ; Knoers, Nine V. ; van der Burgt, Ineke ; de Jong, Pieter J. ; Brunner, Han G. ; van Kessel, Ad Geurts ; Schoenmakers, Eric F. P. M. ; Veltman, Joris A. 

2003-01-01

Microdeletions and microduplications, not visible by routine chromosome analysis, are a major cause of human malformation and mental retardation. Novel high-resolution, whole-genome technologies can improve the diagnostic detection rate of these small chromosomal abnormalities. Array-based comparative genomic hybridization allows such a high-resolution screening by hybridizing differentially labeled test and reference DNAs to arrays consisting of thousands of genomic clones. In this study, we tested the diagnostic capacity of this technology using ∼3,500 flourescent in situ hybridization–verified clones selected to cover the genome with an average of 1 clone per megabase (Mb). The sensitivity and specificity of the technology were tested in normal-versus-normal control experiments and through the screening of patients with known microdeletion syndromes. Subsequently, a series of 20 cytogenetically normal patients with mental retardation and dysmorphisms suggestive of a chromosomal abnormality were analyzed. In this series, three microdeletions and two microduplications were identified and validated. Two of these genomic changes were identified also in one of the parents, indicating that these are large-scale genomic polymorphisms. Deletions and duplications as small as 1 Mb could be reliably detected by our approach. The percentage of false-positive results was reduced to a minimum by use of a dye-swap-replicate analysis, all but eliminating the need for laborious validation experiments and facilitating implementation in a routine diagnostic setting. This high-resolution assay will facilitate the identification of novel genes involved in human mental retardation and/or malformation syndromes and will provide insight into the flexibility and plasticity of the human genome. PMID:14628292

Promises, pitfalls and practicalities of prenatal whole exome sequencing.

PubMed

Best, Sunayna; Wou, Karen; Vora, Neeta; Van der Veyver, Ignatia B; Wapner, Ronald; Chitty, Lyn S

2018-01-01

Prenatal genetic diagnosis provides information for pregnancy and perinatal decision-making and management. In several small series, prenatal whole exome sequencing (WES) approaches have identified genetic diagnoses when conventional tests (karyotype and microarray) were not diagnostic. Here, we review published prenatal WES studies and recent conference abstracts. Thirty-one studies were identified, with diagnostic rates in series of five or more fetuses varying between 6.2% and 80%. Differences in inclusion criteria and trio versus singleton approaches to sequencing largely account for the wide range of diagnostic rates. The data suggest that diagnostic yields will be greater in fetuses with multiple anomalies or in cases preselected following genetic review. Beyond its ability to improve diagnostic rates, we explore the potential of WES to improve understanding of prenatal presentations of genetic disorders and lethal fetal syndromes. We discuss prenatal phenotyping limitations, counselling challenges regarding variants of uncertain significance, incidental and secondary findings, and technical problems in WES. We review the practical, ethical, social and economic issues that must be considered before prenatal WES could become part of routine testing. Finally, we reflect upon the potential future of prenatal genetic diagnosis, including a move towards whole genome sequencing and non-invasive whole exome and whole genome testing. © 2017 John Wiley & Sons, Ltd. © 2017 John Wiley & Sons, Ltd.

Evaluation performance of diagnostic methods of intestinal parasitosis in school age children in Ethiopia.

PubMed

Yimer, Mulat; Hailu, Tadesse; Mulu, Wondemagegn; Abera, Bayeh

2015-12-26

Although the sensitivity of Wet mount technique is questionable, it is the major diagnostic technique for routine diagnosis of intestinal parasitosis in Ethiopia. Therefore, the aim of this study was the evaluation performance of diagnostic methods of intestinal parasitosis in school age children in Ethiopia. A cross sectional study was conducted from May to June 2013. Single stool sample was processed for direct, Formol ether concentration (FEC) and Kato Katz methods. The sensitivity and negative predictive value (NPV) of diagnostic tests were calculated in terms of the "Gold" standard method (the combined result of the three methods altogether). A total of 422 school age children were participated in this study. The prevalence of intestinal parasites was high (74.6%) with Kato Katz technique. The sensitivity of Wet mount, FEC and Kato Katz tests against the Gold standard test was 48.9, 63.1 and 93.7%, respectively. Kato Katz technique revealed a better NPV 80.4 (80.1-80.6) as compared to the Wet mount (33.7%) and FEC techniques (41.3%). In this study, the Kato Katz technique outperformed the other two methods but the true values for sensitivity, specificity and diagnostic values are not known. Moreover, it is labor intensive and not easily accessible. Hence, it is preferable to use FEC technique to complement the Wet mount test.

Contamination with HIV antibody may be responsible for false positive results in specimens tested on automated platforms running HIV 4th generation assays in a region of high HIV prevalence.

PubMed

Hardie, Diana Ruth; Korsman, Stephen N; Hsiao, Nei-Yuan; Morobadi, Molefi Daniel; Vawda, Sabeehah; Goedhals, Dominique

2017-01-01

In South Africa where the prevalence of HIV infection is very high, 4th generation HIV antibody/p24 antigen combo immunoassays are the tests of choice for laboratory based screening. Testing is usually performed in clinical pathology laboratories on automated analysers. To investigate the cause of false positive results on 4th generation HIV testing platforms in public sector laboratories, the performance of two automated platforms was compared in a clinical pathology setting, firstly on routine diagnostic specimens and secondly on known sero-negative samples. Firstly, 1181 routine diagnostic specimens were sequentially tested on Siemens and Roche automated 4th generation platforms. HIV viral load, western blot and follow up testing were used to determine the true status of inconclusive specimens. Subsequently, known HIV seronegative samples from a single donor were repeatedly tested on both platforms and an analyser was tested for surface contamination with HIV positive serum to identify how suspected specimen contamination could be occurring. Serial testing of diagnostic specimens yielded 163 weakly positive or discordant results. Only 3 of 163 were conclusively shown to indicate true HIV infection. Specimen contamination with HIV antibody was suspected, based on the following evidence: the proportion of positive specimens increased on repeated passage through the analysers; viral loads were low or undetectable and western blots negative or indeterminate on problem specimens; screen negative, 2nd test positive specimens tested positive when reanalysed on the screening assay; follow up specimens (where available) were negative. Similarly, an increasing number of known negative specimens became (repeatedly) sero-positive on serial passage through one of the analysers. Internal and external analyser surfaces were contaminated with HIV serum, evidence that sample splashes occur during testing. Due to the extreme sensitivity of these assays, contamination with minute amounts of HIV antibody can cause a negative sample to test positive. Better contamination control measures are needed on analysers used in clinical pathology environments, especially in regions where HIV sero-prevalence is high.

Pathogenesis and Management of Sarcopenia.

PubMed

Dhillon, Robinder J S; Hasni, Sarfaraz

2017-02-01

Sarcopenia represents a loss of muscle strength and mass in older individuals. Sarcopenia in the elderly has now become a major focus of research and public policy debate due to its impact on morbidity, mortality, and health care expenditure. Despite its clinical importance, sarcopenia remains under-recognized and poorly managed in routine clinical practice. This is, in part, due to a lack of available diagnostic testing and uniform diagnostic criteria. The management of sarcopenia is primarily focused on physical therapy for muscle strengthening and gait training. There are no pharmacologic agents for the treatment of sarcopenia. Published by Elsevier Inc.

Effects of diagnostic ionizing radiation on pregnancy via TEM

NASA Astrophysics Data System (ADS)

Mohammed, W. H.; Artoli, A. M.

2008-08-01

In Sudan, X-rays are routinely used at least once for measurements of pelvis during the gestation period, though this is highly prohibited worldwide, except for a few life threatening cases. To demonstrate the effect of diagnostic ionizing radiation on uterus, fetus and neighboring tissues to the ovaries, two independent experiments on pregnant rabbits were conducted. The first experiment was a proof of concept that diagnostic ionizing radiation is hazardous throughout the gestation period. The second experiment was done through Transmission Electron Microscopy (TEM) to elucidate the morphological changes in the ultra structure of samples taken from irradiated pregnant rabbits. This study uses TEM to test the effect of diagnostic radiation of less than 0.6 Gray on the cellular level. Morphological changes have been captured and the images were analyzed to quantify these effects.

Identification of trisomy 18, trisomy 13, and Down syndrome from maternal plasma.

PubMed

Gekas, Jean; Langlois, Sylvie; Ravitsky, Vardit; Audibert, François; van den Berg, David-Gradus; Haidar, Hazar; Rousseau, François

2014-01-01

Current prenatal diagnosis for fetal aneuploidies (including trisomy 21 [T21]) generally relies on an initial biochemical serum-based noninvasive prenatal testing (NIPT) after which women who are deemed to be at high risk are offered an invasive confirmatory test (amniocentesis or chorionic villi sampling for a fetal karyotype), which is associated with a risk of fetal miscarriage. Recently, genomics-based NIPT (gNIPT) was proposed for the analysis of fetal genomic DNA circulating in maternal blood. The diffusion of this technology in routine prenatal care could be a major breakthrough in prenatal diagnosis, since initial research studies suggest that this novel approach could be very effective and could reduce substantially the number of invasive procedures. However, the limitations of gNIPT may be underappreciated. In this review, we examine currently published literature on gNIPT to highlight advantages and limitations. At this time, the performance of gNIPT is relatively well-documented only in high-risk pregnancies for T21 and trisomy 18. This additional screening test may be an option for women classified as high-risk of aneuploidy who wish to avoid invasive diagnostic tests, but it is crucial that providers carefully counsel patients about the test's advantages and limitations. The gNIPT is currently not recommended as a first-tier prenatal screening test for T21. Since gNIPT is not considered as a diagnostic test, a positive gNIPT result should always be confirmed by an invasive test, such as amniocentesis or chorionic villus sampling. Validation studies are needed to optimally introduce this technology into the existing routine workflow of prenatal care.

External quality assessment of dengue and chikungunya diagnostics in the Asia Pacific region, 2015

PubMed Central

Soh, Li Ting; Squires, Raynal C; Tan, Li Kiang; Pok, Kwoon Yong; Yang, HuiTing; Liew, Christina; Shah, Aparna Singh; Aaskov, John; Abubakar, Sazaly; Hasabe, Futoshi; Ng, Lee Ching

2016-01-01

Objective To conduct an external quality assessment (EQA) of dengue and chikungunya diagnostics among national-level public health laboratories in the Asia Pacific region following the first round of EQA for dengue diagnostics in 2013. Methods Twenty-four national-level public health laboratories performed routine diagnostic assays on a proficiency testing panel consisting of two modules. Module A contained serum samples spiked with cultured dengue virus (DENV) or chikungunya virus (CHIKV) for the detection of nucleic acid and DENV non-structural protein 1 (NS1) antigen. Module B contained human serum samples for the detection of anti-DENV antibodies. Results Among 20 laboratories testing Module A, 17 (85%) correctly detected DENV RNA by reverse transcription polymerase chain reaction (RT–PCR), 18 (90%) correctly determined serotype and 19 (95%) correctly identified CHIKV by RT–PCR. Ten of 15 (66.7%) laboratories performing NS1 antigen assays obtained the correct results. In Module B, 18/23 (78.3%) and 20/20 (100%) of laboratories correctly detected anti-DENV IgM and IgG, respectively. Detection of acute/recent DENV infection by both molecular (RT–PCR) and serological methods (IgM) was available in 19/24 (79.2%) participating laboratories. Discussion Accurate laboratory testing is a critical component of dengue and chikungunya surveillance and control. This second round of EQA reveals good proficiency in molecular and serological diagnostics of these diseases in the Asia Pacific region. Further comprehensive diagnostic testing, including testing for Zika virus, should comprise future iterations of the EQA. PMID:27508088

Clinical applications of MS-based protein quantification.

PubMed

Sabbagh, Bassel; Mindt, Sonani; Neumaier, Michael; Findeisen, Peter

2016-04-01

Mass spectrometry-based assays are increasingly important in clinical laboratory medicine and nowadays are already commonly used in several areas of routine diagnostics. These include therapeutic drug monitoring, toxicology, endocrinology, pediatrics, and microbiology. Accordingly, some of the most common analyses are therapeutic drug monitoring of immunosuppressants, vitamin D, steroids, newborn screening, and bacterial identification. However, MS-based quantification of peptides and proteins for routine diagnostic use is rather rare up to now despite excellent analytical specificity and good sensitivity. Here, we want to give an overview over current fit-for-purpose assays for MS-based protein quantification. Advantages as well as challenges of this approach will be discussed with focus on feasibility for routine diagnostic use. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Photoplethysmography using a smartphone application for assessment of ulnar artery patency: a randomized clinical trial

PubMed Central

Di Santo, Pietro; Harnett, David T.; Simard, Trevor; Ramirez, F. Daniel; Pourdjabbar, Ali; Yousef, Altayyeb; Moreland, Robert; Bernick, Jordan; Wells, George; Dick, Alexander; Le May, Michel; Labinaz, Marino; So, Derek; Motazedian, Pouya; Jung, Richard G.; Chandrasekhar, Jaya; Mehran, Roxana; Chong, Aun-Yeong

2018-01-01

BACKGROUND: Radial artery access is commonly performed for coronary angiography and invasive hemodynamic monitoring. Despite limitations in diagnostic accuracy, the modified Allen test (manual occlusion of radial and ulnar arteries followed by release of the latter and assessment of palmar blush) is used routinely to evaluate the collateral circulation to the hand and, therefore, to determine patient eligibility for radial artery access. We sought to evaluate whether a smartphone application may provide a superior alternative to the modified Allen test. METHODS: We compared the modified Allen test with a smartphone heart rate–monitoring application (photoplethysmography readings detected using a smartphone camera lens placed on the patient’s index finger) in patients undergoing a planned cardiac catheterization. Test order was randomly assigned in a 1:1 fashion. All patients then underwent conventional plethysmography of the index finger, followed by Doppler ultrasonography of the radial and ulnar arteries (the diagnostic standard). The primary outcome was diagnostic accuracy of the heart rate–monitoring application. RESULTS: Among 438 patients who were included in the study, we found that the heart rate–monitoring application had a superior diagnostic accuracy compared with the modified Allen test (91.8% v. 81.7%, p = 0.002), attributable to its greater specificity (93.0% v. 82.8%, p = 0.001). We also found that this application had greater diagnostic accuracy for assessment of radial or ulnar artery patency in the ipsilateral and contralateral wrist (94.0% v. 84.0%, p < 0.001). INTERPRETATION: A smartphone application used at the bedside was diagnostically superior to traditional physical examination for confirming ulnar patency before radial artery access. This study highlights the potential for smartphone-based diagnostics to aid in clinical decision-making at the patient’s bedside. Trial registration: Clinicaltrials.gov, no. NCT02519491. PMID:29615421

Photoplethysmography using a smartphone application for assessment of ulnar artery patency: a randomized clinical trial.

PubMed

Di Santo, Pietro; Harnett, David T; Simard, Trevor; Ramirez, F Daniel; Pourdjabbar, Ali; Yousef, Altayyeb; Moreland, Robert; Bernick, Jordan; Wells, George; Dick, Alexander; Le May, Michel; Labinaz, Marino; So, Derek; Motazedian, Pouya; Jung, Richard G; Chandrasekhar, Jaya; Mehran, Roxana; Chong, Aun-Yeong; Hibbert, Benjamin

2018-04-03

Radial artery access is commonly performed for coronary angiography and invasive hemodynamic monitoring. Despite limitations in diagnostic accuracy, the modified Allen test (manual occlusion of radial and ulnar arteries followed by release of the latter and assessment of palmar blush) is used routinely to evaluate the collateral circulation to the hand and, therefore, to determine patient eligibility for radial artery access. We sought to evaluate whether a smartphone application may provide a superior alternative to the modified Allen test. We compared the modified Allen test with a smartphone heart rate-monitoring application (photoplethysmography readings detected using a smartphone camera lens placed on the patient's index finger) in patients undergoing a planned cardiac catheterization. Test order was randomly assigned in a 1:1 fashion. All patients then underwent conventional plethysmography of the index finger, followed by Doppler ultrasonography of the radial and ulnar arteries (the diagnostic standard). The primary outcome was diagnostic accuracy of the heart rate-monitoring application. Among 438 patients who were included in the study, we found that the heart rate-monitoring application had a superior diagnostic accuracy compared with the modified Allen test (91.8% v. 81.7%, p = 0.002), attributable to its greater specificity (93.0% v. 82.8%, p = 0.001). We also found that this application had greater diagnostic accuracy for assessment of radial or ulnar artery patency in the ipsilateral and contralateral wrist (94.0% v. 84.0%, p < 0.001). A smartphone application used at the bedside was diagnostically superior to traditional physical examination for confirming ulnar patency before radial artery access. This study highlights the potential for smartphone-based diagnostics to aid in clinical decision-making at the patient's bedside. Trial registration: Clinicaltrials.gov, no. NCT02519491. © 2018 Joule Inc. or its licensors.

Pharmacologic intervention as an alternative to exercise stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gould, K.L.

1987-04-01

Although thallium exercise imaging has served an important role in clinical cardiology, it is significantly limited by suboptimal sensitivity and specificity, particularly in asymptomatic man. The increasing recognition of silent myocardial ischemia, the significant prevalence of coronary artery disease in asymptomatic middle age men, and the frequent occurrence of myocardial infarction without preceding symptoms in 60% of cases emphasizes the need for a more definitive, noninvasive diagnostic test for the presence of coronary artery disease suitable for screening in asymptomatic or symptomatic patients. Intravenous dipyridamole combined with handgrip stress provides a potent stimulus for purposes of diagnostic perfusion imaging. Althoughmore » planar and single photon emission computed tomography (SPECT) imaging also have played an important role, these techniques are seriously hindered by their inability to quantitate radiotracer uptake or image modest differences in maximum relative flow caused by coronary artery stenosis. Accordingly, the combination of dipyridamole-handgrip stress with positron imaging of myocardial perfusion has become a powerful diagnostic tool suitable for routine clinical use. With the availability of generator-produced rubidium-82, dedicated clinically oriented positron cameras, the routine application of positron imaging to clinical cardiology has become feasible. 75 references.« less

Our experiences with the use of atopy patch test in the diagnosis of cow's milk hypersensitivity.

PubMed

Pustisek, Nives; Jaklin-Kekez, Alemka; Frkanec, Ruza; Sikanić-Dugić, Nives; Misak, Zrinjka; Jadresin, Oleg; Kolacek, Sanja

2010-01-01

Atopy patch test has been recognized as a diagnostic tool for the verification of food allergies in infants and small children suffering from atopic dermatitis. The test also has a role in the diagnosis of food allergies characterized by clinical signs associated with the digestive system. Yet, in spite of numerous studies, the test itself has hitherto not been standardized. Our study enlisted 151 children less than two years of age, who exhibited suspect skin and/or gastrointestinal manifestations of food allergy to cow's milk, and in whom tests failed to prove early type of allergic reaction. Atopy patch test was positive in 28% of the children with atopic dermatitis, 43% of the children with suspect gastrointestinal manifestation and 32% of the children with skin and gastrointestinal manifestations of food allergy. In our experience, atopy patch test is an excellent addition to the hitherto used tests for the diagnosis of food allergies. It targets specifically delayed type hypersensitivity reactions, which are difficult to confirm with other diagnostic tools. It is furthermore simple to perform, noninvasive and produces a minimum of undesired side effects. For these reasons, it should become part of the routine diagnostic toolset for food allergies to cow's milk in infants and children, and applied before a food challenge test.

Normal pressure hydrocephalus: survey on contemporary diagnostic algorithms and therapeutic decision-making in clinical practice.

PubMed

Krauss, J K; Halve, B

2004-04-01

There is no agreement on the best diagnostic criteria for selecting patients with normal pressure hydrocephalus (NPH) for CSF shunting. The primary objective of the present study was to provide a contemporary survey on diagnostic algorithms and therapeutic decision-making in clinical practice. The secondary objective was to estimate the incidence of NPH. Standardized questionnaires with sections on the incidence of NPH and the frequency of shunting, evaluation of clinical symptoms, and signs, diagnostic studies, therapeutic decision-making and operative techniques, postoperative outcome and complications, and the profiles of different centers, were sent to 82 neurosurgical centers in Germany known to participate in the care of patients with NPH. Data were analyzed from 49 of 53 centers which responded to the survey (65%). The estimated annual incidence of NPH was 1.8 cases/100.000 inhabitants. Gait disturbance was defined as the most important sign of NPH (61%). There was a wide variety in the choice of diagnostic tests. Cisternography was performed routinely only in single centers. Diagnostic CSF removal was used with varying frequency by all centers except one, but the amount of CSF removed by lumbar puncture differed markedly between centers. There was poor agreement on criteria for evaluation of continuous intracranial pressure recordings regarding both the amplitude and the relative frequency of B-waves. Both periventricular and deep white matter lesions were present in about 50% of patients being shunted, indicating that vascular comorbidity in NPH patients has gained more acceptance. Programmable shunts were used by more than half of the centers, and newer valve types such as gravitational valves have become more popular. According to the present survey, new diagnostic and therapeutic concepts on NPH have penetrated daily routine to a certain extent. Wide variability, however, still exists among different neurosurgical centers.

Molecular diagnosis of microbial aetiologies using SepsiTest™ in the daily routine of a diagnostic laboratory.

PubMed

Haag, Heike; Locher, Franziska; Nolte, Oliver

2013-08-01

A universal PCR and sequencing test, SepsiTest™ (Molzym, Germany) was evaluated for its applicability during daily diagnostic routine in a privately operated laboratory. In total, 96 specimens originating from 66 patients under suspect of infectious endocarditis, infections of joints, encephalitis/meningitis, systemic infections and infections of unknown genesis were PCR analysed and compared to culture results. Samples comprised cultured and non-cultured blood, synovial fluid, synovial tissue, heart valves, pacemakers, spinal tissue, cerebrospinal fluid, and swabs. PCR and culture were concordant in 26 negative and 8 positive cases (51.5%). A group of 25 patients was culture-negative but PCR-positive (37.9%). In at least 14 of these, common and/or rare aetiologies were identified, while for 4 patients the results of 16S PCR could not be unequivocally linked with the underlying disease. Benefits and limitations of the molecular test are discussed with special emphasis on technical and economic issues. In conclusion, SepsiTest™ proved to be a valuable tool for the diagnosis of aetiologies, particularly in cases of culture-negative patients who are under strong suspicion for an infection. Copyright © 2013 Elsevier Inc. All rights reserved.

Diagnostic value of non stress test in latent phase of labor and maternal and fetal outcomes.

PubMed

Raouf, Shiva; Sheikhan, Fatemeh; Hassanpour, Shirin; Bani, Soheila; Torabi, Rogayye; Shamsalizadeh, Neda

2014-10-28

The Non Stress Test (NST) is the one of the significant diagnostic fetal well being testes. The purpose of this study is to access diagnostic value of NST during latent phase of labor by considering maternal and neonatal outcomes. This case study control study was performed on 450 healthy pregnant women with gestational age between 38-42 weeks in AL-Zahra teaching hospital in Tabriz, Iran. All participants underwent NST after being admitted to labor during their latent phase of delivery. Participants were divided into groups including the study group which included 150 participants with non-reactive NST results whereas 300 subjects with reactive NST results assigned in the control group. Subjects in both groups were hospitalized for pregnancy termination because of the delivery time. In order to find out the importance of routine performance of NST during delivery, the relationship between NST results and maternal and fetal outcomes was evaluated. Several criteria including type of delivery, meconium defecation, descent arrest, bradicardia, Apgar score, and still birth were compared between two types. Finding of this study showed that descent arrest occurred in 2.7% of the subjects in the study group, whereas it occurred in 4.7% of the participants in the control group (p=0.44). Bradicardia found in 28% of the participants in study group and 3.3% of the control group (p<0.001). The low Apgar Score was found in 2.7% of case group however; no the low apgar score detected in the control group. Meconium defecation observed in 11.3% of the subjects in the study group and 9.7% of the participants in control group (p=0.62). The amount of stillbirth were found in control group. There was a significant difference between the results of both groups in terms of bradicardia, descent arrest, and the low Apgar score and cesarean section. Results of this study revealed that participants in study group with nonreactive NST results had more fetal complications than those with reactive NST results. NST was found to be a value diagnostic test for diagnosis of fetal distress during delivery in the latent phase. This findings of this study suggest that NST should be performed routinely as a valuable diagnostic test during the latent phase of delivery.

Diagnosis and treatment of dementia: 2. Diagnosis

PubMed Central

Feldman, Howard H.; Jacova, Claudia; Robillard, Alain; Garcia, Angeles; Chow, Tiffany; Borrie, Michael; Schipper, Hyman M.; Blair, Mervin; Kertesz, Andrew; Chertkow, Howard

2008-01-01

Background Dementia can now be accurately diagnosed through clinical evaluation, cognitive screening, basic laboratory evaluation and structural imaging. A large number of ancillary techniques are also available to aid in diagnosis, but their role in the armamentarium of family physicians remains controversial. In this article, we provide physicians with practical guidance on the diagnosis of dementia based on recommendations from the Third Canadian Consensus Conference on the Diagnosis and Treatment of Dementia, held in March 2006. Methods We developed evidence-based guidelines using systematic literature searches, with specific criteria for study selection and quality assessment, and a clear and transparent decision-making process. We selected studies published from January 1996 to December 2005 that pertained to key diagnostic issues in dementia. We graded the strength of evidence using the criteria of the Canadian Task Force on Preventive Health Care. Results Of the 1591 articles we identified on all aspects of dementia diagnosis, 1095 met our inclusion criteria; 620 were deemed to be of good or fair quality. From a synthesis of the evidence in these studies, we made 32 recommendations related to the diagnosis of dementia. There are clinical criteria for diagnosing most forms of dementia. A standard diagnostic evaluation can be performd by family physicians over multiple visits. It involves a clinical history (from patient and caregiver), a physical examination and brief cognitive testing. A list of core laboratory tests is recommended. Structural imaging with computed tomography or magnetic resonance imaging is recommended in selected cases to rule out treatable causes of dementia or to rule in cerebrovascular disease. There is insufficient evidence to recommend routine functional imaging, measurement of biomarkers or neuropsychologic testing. Interpretation The diagnosis of dementia remains clinically integrative based on history, physical examination and brief cognitive testing. A number of core laboratory tests are also recommended. Structural neuroimaging is advised in selected cases. Other diagnostic approaches, including functional neuroimaging, neuropsychological testing and measurement of biomarkers, have shown promise but are not yet recommended for routine use by family physicians. PMID:18362376

Laboratory diagnosis of Ebola virus disease and corresponding biosafety considerations in the China Ebola Treatment Center.

PubMed

Huang, Qing; Fu, Wei-Ling; You, Jian-Ping; Mao, Qing

2016-10-01

Ebola virus disease (EVD), caused by Ebola virus (EBOV), is a potent acute infectious disease with a high case-fatality rate. Etiological and serological EBOV detection methods, including techniques that involve the detection of the viral genome, virus-specific antigens and anti-virus antibodies, are standard laboratory diagnostic tests that facilitate confirmation or exclusion of EBOV infection. In addition, routine blood tests, liver and kidney function tests, electrolytes and coagulation tests and other diagnostic examinations are important for the clinical diagnosis and treatment of EVD. Because of the viral load in body fluids and secretions from EVD patients, all body fluids are highly contagious. As a result, biosafety control measures during the collection, transport and testing of clinical specimens obtained from individuals scheduled to undergo EBOV infection testing (including suspected, probable and confirmed cases) are crucial. This report has been generated following extensive work experience in the China Ebola Treatment Center (ETC) in Liberia and incorporates important information pertaining to relevant diagnostic standards, clinical significance, operational procedures, safety controls and other issues related to laboratory testing of EVD. Relevant opinions and suggestions are presented in this report to provide contextual awareness associated with the development of standards and/or guidelines related to EVD laboratory testing.

Testing for Drug Hypersensitivity Syndromes

PubMed Central

Rive, Craig M; Bourke, Jack; Phillips, Elizabeth J

2013-01-01

Adverse drug reactions are a common cause of patient morbidity and mortality. Type B drug reactions comprise only 20% of all drug reactions but they tend to be primarily immunologically mediated and less dependent on the drug’s pharmacological action and dose. Common Type B reactions seen in clinical practice are those of the immediate, IgE, Gell-Coombs Type I reactions, and the delayed, T-cell mediated, Type IV reactions. Management of these types of reactions, once they have occurred, requires careful consideration and recognition of the utility of routine diagnostic tests followed by ancillary specialised diagnostic testing. For Type I, IgE mediated reactions this includes prick/intradermal skin testing and oral provocation. For Type IV, T-cell mediated reactions this includes a variety of in vivo (patch testing) and ex vivo tests, many of which are currently mainly used in highly specialised research laboratories. The recent association of many serious delayed (Type IV) hypersensitivity reactions to specific drugs with HLA class I and II alleles has created the opportunity for HLA screening to exclude high risk populations from exposure to the implicated drug and hence prevent clinical reactions. For example, the 100% negative predictive value of HLA-B*5701 for true immunologically mediated abacavir hypersensitivity and the development of feasible, inexpensive DNA-based molecular tests has led to incorporation of HLA-B*5701 screening in routine HIV clinical practice. The mechanism by which drugs specifically interact with HLA has been recently characterised and promises to lead to strategies for pre-clinical screening to inform drug development and design. PMID:23592889

Update on diagnostic value of breath test in gastrointestinal and liver diseases

PubMed Central

Siddiqui, Imran; Ahmed, Sibtain; Abid, Shahab

2016-01-01

In the field of gastroenterology, breath tests (BTs) are used intermittently as diagnostic tools that allow indirect, non-invasive and relatively less cumbersome evaluation of several disorders by simply quantifying the appearance in exhaled breath of a metabolite of a specific substrate administered. The aim of this review is to have an insight into the principles, methods of analysis and performance parameters of various hydrogen, methane and carbon BTs which are available for diagnosing gastrointestinal disorders such as Helicobacter pylori infection, small intestinal bacterial overgrowth, and carbohydrate malabsorption. Evaluation of gastric emptying is routinely performed by scintigraphy which is however, difficult to perform and not suitable for children and pregnant women, this review has abridged the 13C-octanoic acid test in comparison to scintigraphy and has emphasized on its working protocol and challenges. A new development such as electronic nose test is also highlighted. Moreover we have also explored the limitations and constraints restraining the wide use of these BT. We conclude that breath testing has an enormous potential to be used as a diagnostic modality. In addition it offers distinct advantages over the traditional invasive methods commonly employed. PMID:27574563

Rapid, comprehensive, and affordable mycobacterial diagnosis with whole-genome sequencing: a prospective study

PubMed Central

Pankhurst, Louise J; del Ojo Elias, Carlos; Votintseva, Antonina A; Walker, Timothy M; Cole, Kevin; Davies, Jim; Fermont, Jilles M; Gascoyne-Binzi, Deborah M; Kohl, Thomas A; Kong, Clare; Lemaitre, Nadine; Niemann, Stefan; Paul, John; Rogers, Thomas R; Roycroft, Emma; Smith, E Grace; Supply, Philip; Tang, Patrick; Wilcox, Mark H; Wordsworth, Sarah; Wyllie, David; Xu, Li; Crook, Derrick W

2016-01-01

Summary Background Slow and cumbersome laboratory diagnostics for Mycobacterium tuberculosis complex (MTBC) risk delayed treatment and poor patient outcomes. Whole-genome sequencing (WGS) could potentially provide a rapid and comprehensive diagnostic solution. In this prospective study, we compare real-time WGS with routine MTBC diagnostic workflows. Methods We compared sequencing mycobacteria from all newly positive liquid cultures with routine laboratory diagnostic workflows across eight laboratories in Europe and North America for diagnostic accuracy, processing times, and cost between Sept 6, 2013, and April 14, 2014. We sequenced specimens once using local Illumina MiSeq platforms and processed data centrally using a semi-automated bioinformatics pipeline. We identified species or complex using gene presence or absence, predicted drug susceptibilities from resistance-conferring mutations identified from reference-mapped MTBC genomes, and calculated genetic distance to previously sequenced UK MTBC isolates to detect outbreaks. WGS data processing and analysis was done by staff masked to routine reference laboratory and clinical results. We also did a microcosting analysis to assess the financial viability of WGS-based diagnostics. Findings Compared with routine results, WGS predicted species with 93% (95% CI 90–96; 322 of 345 specimens; 356 mycobacteria specimens submitted) accuracy and drug susceptibility also with 93% (91–95; 628 of 672 specimens; 168 MTBC specimens identified) accuracy, with one sequencing attempt. WGS linked 15 (16% [95% CI 10–26]) of 91 UK patients to an outbreak. WGS diagnosed a case of multidrug-resistant tuberculosis before routine diagnosis was completed and discovered a new multidrug-resistant tuberculosis cluster. Full WGS diagnostics could be generated in a median of 9 days (IQR 6–10), a median of 21 days (IQR 14–32) faster than final reference laboratory reports were produced (median of 31 days [IQR 21–44]), at a cost of £481 per culture-positive specimen, whereas routine diagnosis costs £518, equating to a WGS-based diagnosis cost that is 7% cheaper annually than are present diagnostic workflows. Interpretation We have shown that WGS has a scalable, rapid turnaround, and is a financially feasible method for full MTBC diagnostics. Continued improvements to mycobacterial processing, bioinformatics, and analysis will improve the accuracy, speed, and scope of WGS-based diagnosis. Funding National Institute for Health Research, Department of Health, Wellcome Trust, British Colombia Centre for Disease Control Foundation for Population and Public Health, Department of Clinical Microbiology, Trinity College Dublin. PMID:26669893

[Digital vs. analog hearing aids for children. Is there a method for making an objective comparison possible?].

PubMed

Prinz, I; Nubel, K; Gross, M

2002-09-01

Until now, the assumed benefits of digital hearing aids are reflected only in subjective descriptions by patients with hearing aids, but cannot be documented adequately by routine diagnostic methods. Seventeen schoolchildren with moderate severe bilateral symmetrical sensorineural hearing loss were examined in a double-blinded crossover study. Differences in performance between a fully digital hearing aid (DigiFocus compact/Oticon) and an analogous digitally programmable two-channel hearing aid were evaluated. Of the 17 children, 13 choose the digital and 4 the analogous hearing aid. In contrast to the clear subjective preferences for the fully digital hearing aid, we could not obtain any significant results with routine diagnostic methods. Using the "virtual hearing aid," a subjective comparison and speech recognition performance task yielded significant differences. The virtual hearing aid proved to be suitable for a direct comparison of different hearing aids and can be used for double-blind testing in a pediatric population.

Central implementation strategies outperform local ones in improving HIV testing in Veterans Healthcare Administration facilities.

PubMed

Goetz, Matthew Bidwell; Hoang, Tuyen; Knapp, Herschel; Burgess, Jane; Fletcher, Michael D; Gifford, Allen L; Asch, Steven M

2013-10-01

Pilot data suggest that a multifaceted approach may increase HIV testing rates, but the scalability of this approach and the level of support needed for successful implementation remain unknown. To evaluate the effectiveness of a scaled-up multi-component intervention in increasing the rate of risk-based and routine HIV diagnostic testing in primary care clinics and the impact of differing levels of program support. Three arm, quasi-experimental implementation research study. Veterans Health Administration (VHA) facilities. Persons receiving primary care between June 2009 and September 2011 INTERVENTION: A multimodal program, including a real-time electronic clinical reminder to facilitate HIV testing, provider feedback reports and provider education, was implemented in Central and Local Arm Sites; sites in the Central Arm also received ongoing programmatic support. Control Arm sites had no intervention Frequency of performing HIV testing during the 6 months before and after implementation of a risk-based clinical reminder (phase I) or routine clinical reminder (phase II). The adjusted rate of risk-based testing increased by 0.4 %, 5.6 % and 10.1 % in the Control, Local and Central Arms, respectively (all comparisons, p < 0.01). During phase II, the adjusted rate of routine testing increased by 1.1 %, 6.3 % and 9.2 % in the Control, Local and Central Arms, respectively (all comparisons, p < 0.01). At study end, 70-80 % of patients had been offered an HIV test. Use of clinical reminders, provider feedback, education and social marketing significantly increased the frequency at which HIV testing is offered and performed in VHA facilities. These findings support a multimodal approach toward achieving the goal of having every American know their HIV status as a matter of routine clinical practice.

Microfluidic Sample Preparation for Diagnostic Cytopathology

PubMed Central

Mach, Albert J.; Adeyiga, Oladunni B.; Di Carlo, Dino

2014-01-01

The cellular components of body fluids are routinely analyzed to identify disease and treatment approaches. While significant focus has been placed on developing cell analysis technologies, tools to automate the preparation of cellular specimens have been more limited, especially for body fluids beyond blood. Preparation steps include separating, concentrating, and exposing cells to reagents. Sample preparation continues to be routinely performed off-chip by technicians, preventing cell-based point-of-care diagnostics, increasing the cost of tests, and reducing the consistency of the final analysis following multiple manually-performed steps. Here, we review the assortment of biofluids for which suspended cells are analyzed, along with their characteristics and diagnostic value. We present an overview of the conventional sample preparation processes for cytological diagnosis. We finally discuss the challenges and opportunities in developing microfluidic devices for the purpose of automating or miniaturizing these processes, with particular emphases on preparing large or small volume samples, working with samples of high cellularity, automating multi-step processes, and obtaining high purity subpopulations of cells. We hope to convey the importance of and help identify new research directions addressing the vast biological and clinical applications in preparing and analyzing the array of available biological fluids. Successfully addressing the challenges described in this review can lead to inexpensive systems to improve diagnostic accuracy while simultaneously reducing overall systemic healthcare costs. PMID:23380972

Routine clinical knee MR reports: comparison of diagnostic performance at 1.5 T and 3.0 T for assessment of the articular cartilage.

PubMed

Mandell, Jacob C; Rhodes, Jeffrey A; Shah, Nehal; Gaviola, Glenn C; Gomoll, Andreas H; Smith, Stacy E

2017-11-01

Accurate assessment of knee articular cartilage is clinically important. Although 3.0 Tesla (T) MRI is reported to offer improved diagnostic performance, literature regarding the clinical impact of MRI field strength is lacking. The purpose of this study is to compare the diagnostic performance of clinical MRI reports for assessment of cartilage at 1.5 and 3.0 T in comparison to arthroscopy. This IRB-approved retrospective study consisted of 300 consecutive knees in 297 patients who had routine clinical MRI and arthroscopy. Descriptions of cartilage from MRI reports of 165 knees at 1.5 T and 135 at 3.0 T were compared with arthroscopy. The sensitivity, specificity, percent of articular surfaces graded concordantly, and percent of articular surfaces graded within one grade of the arthroscopic grading were calculated for each articular surface at 1.5 and 3.0 T. Agreement between MRI and arthroscopy was calculated with the weighted-kappa statistic. Significance testing was performed utilizing the z-test after bootstrapping to obtain the standard error. The sensitivity, specificity, percent of articular surfaces graded concordantly, and percent of articular surfaces graded within one grade were 61.4%, 82.7%, 62.2%, and 77.5% at 1.5 T and 61.8%, 80.6%, 59.5%, and 75.6% at 3.0 T, respectively. The weighted kappa statistic was 0.56 at 1.5 T and 0.55 at 3.0 T. There was no statistically significant difference in any of these parameters between 1.5 and 3.0 T. Factors potentially contributing to the lack of diagnostic advantage of 3.0 T MRI are discussed.

Optimization and validation of sample preparation for metagenomic sequencing of viruses in clinical samples.

PubMed

Lewandowska, Dagmara W; Zagordi, Osvaldo; Geissberger, Fabienne-Desirée; Kufner, Verena; Schmutz, Stefan; Böni, Jürg; Metzner, Karin J; Trkola, Alexandra; Huber, Michael

2017-08-08

Sequence-specific PCR is the most common approach for virus identification in diagnostic laboratories. However, as specific PCR only detects pre-defined targets, novel virus strains or viruses not included in routine test panels will be missed. Recently, advances in high-throughput sequencing allow for virus-sequence-independent identification of entire virus populations in clinical samples, yet standardized protocols are needed to allow broad application in clinical diagnostics. Here, we describe a comprehensive sample preparation protocol for high-throughput metagenomic virus sequencing using random amplification of total nucleic acids from clinical samples. In order to optimize metagenomic sequencing for application in virus diagnostics, we tested different enrichment and amplification procedures on plasma samples spiked with RNA and DNA viruses. A protocol including filtration, nuclease digestion, and random amplification of RNA and DNA in separate reactions provided the best results, allowing reliable recovery of viral genomes and a good correlation of the relative number of sequencing reads with the virus input. We further validated our method by sequencing a multiplexed viral pathogen reagent containing a range of human viruses from different virus families. Our method proved successful in detecting the majority of the included viruses with high read numbers and compared well to other protocols in the field validated against the same reference reagent. Our sequencing protocol does work not only with plasma but also with other clinical samples such as urine and throat swabs. The workflow for virus metagenomic sequencing that we established proved successful in detecting a variety of viruses in different clinical samples. Our protocol supplements existing virus-specific detection strategies providing opportunities to identify atypical and novel viruses commonly not accounted for in routine diagnostic panels.

ACOG Technology Assessment No. 11: Genetics and molecular diagnostic testing.

PubMed

2014-02-01

Human genetics and molecular testing are playing an increasingly important role in medicine, including obstetric and gynecologic practice. As the genetic basis for reproductive disorders, common diseases, and cancer is elucidated with improved molecular technology, genetic testing opportunities are expanding and influencing treatment options and prevention strategies. It is essential that obstetrician-gynecologists be aware of advances in the understanding of genetic disease and the fundamental principles of genetic screening and molecular testing as genetics becomes a more integral part of routine medical practice. This document reviews the basics of genetic transmission and genetic technologies in current use.

Performance analysis of automated evaluation of Crithidia luciliae-based indirect immunofluorescence tests in a routine setting - strengths and weaknesses.

PubMed

Hormann, Wymke; Hahn, Melanie; Gerlach, Stefan; Hochstrate, Nicola; Affeldt, Kai; Giesen, Joyce; Fechner, Kai; Damoiseaux, Jan G M C

2017-11-27

Antibodies directed against dsDNA are a highly specific diagnostic marker for the presence of systemic lupus erythematosus and of particular importance in its diagnosis. To assess anti-dsDNA antibodies, the Crithidia luciliae-based indirect immunofluorescence test (CLIFT) is one of the assays considered to be the best choice. To overcome the drawback of subjective result interpretation that inheres indirect immunofluorescence assays in general, automated systems have been introduced into the market during the last years. Among these systems is the EUROPattern Suite, an advanced automated fluorescence microscope equipped with different software packages, capable of automated pattern interpretation and result suggestion for ANA, ANCA and CLIFT analysis. We analyzed the performance of the EUROPattern Suite with its automated fluorescence interpretation for CLIFT in a routine setting, reflecting the everyday life of a diagnostic laboratory. Three hundred and twelve consecutive samples were collected, sent to the Central Diagnostic Laboratory of the Maastricht University Medical Centre with a request for anti-dsDNA analysis over a period of 7 months. Agreement between EUROPattern assay analysis and the visual read was 93.3%. Sensitivity and specificity were 94.1% and 93.2%, respectively. The EUROPattern Suite performed reliably and greatly supported result interpretation. Automated image acquisition is readily performed and automated image classification gives a reliable recommendation for assay evaluation to the operator. The EUROPattern Suite optimizes workflow and contributes to standardization between different operators or laboratories.

Cost-effective Diagnostic Checklists for Meningitis in Resource Limited Settings

PubMed Central

Durski, Kara N.; Kuntz, Karen M.; Yasukawa, Kosuke; Virnig, Beth A.; Meya, David B.; Boulware, David R.

2013-01-01

Background Checklists can standardize patient care, reduce errors, and improve health outcomes. For meningitis in resource-limited settings, with high patient loads and limited financial resources, CNS diagnostic algorithms may be useful to guide diagnosis and treatment. However, the cost-effectiveness of such algorithms is unknown. Methods We used decision analysis methodology to evaluate the costs, diagnostic yield, and cost-effectiveness of diagnostic strategies for adults with suspected meningitis in resource limited settings with moderate/high HIV prevalence. We considered three strategies: 1) comprehensive “shotgun” approach of utilizing all routine tests; 2) “stepwise” strategy with tests performed in a specific order with additional TB diagnostics; 3) “minimalist” strategy of sequential ordering of high-yield tests only. Each strategy resulted in one of four meningitis diagnoses: bacterial (4%), cryptococcal (59%), TB (8%), or other (aseptic) meningitis (29%). In model development, we utilized prevalence data from two Ugandan sites and published data on test performance. We validated the strategies with data from Malawi, South Africa, and Zimbabwe. Results The current comprehensive testing strategy resulted in 93.3% correct meningitis diagnoses costing $32.00/patient. A stepwise strategy had 93.8% correct diagnoses costing an average of $9.72/patient, and a minimalist strategy had 91.1% correct diagnoses costing an average of $6.17/patient. The incremental cost effectiveness ratio was $133 per additional correct diagnosis for the stepwise over minimalist strategy. Conclusions Through strategically choosing the order and type of testing coupled with disease prevalence rates, algorithms can deliver more care more efficiently. The algorithms presented herein are generalizable to East Africa and Southern Africa. PMID:23466647

A comprehensive custom panel design for routine hereditary cancer testing: preserving control, improving diagnostics and revealing a complex variation landscape.

PubMed

Castellanos, Elisabeth; Gel, Bernat; Rosas, Inma; Tornero, Eva; Santín, Sheila; Pluvinet, Raquel; Velasco, Juan; Sumoy, Lauro; Del Valle, Jesús; Perucho, Manuel; Blanco, Ignacio; Navarro, Matilde; Brunet, Joan; Pineda, Marta; Feliubadaló, Lidia; Capellá, Gabi; Lázaro, Conxi; Serra, Eduard

2017-01-04

We wanted to implement an NGS strategy to globally analyze hereditary cancer with diagnostic quality while retaining the same degree of understanding and control we had in pre-NGS strategies. To do this, we developed the I2HCP panel, a custom bait library covering 122 hereditary cancer genes. We improved bait design, tested different NGS platforms and created a clinically driven custom data analysis pipeline. The I2HCP panel was developed using a training set of hereditary colorectal cancer, hereditary breast and ovarian cancer and neurofibromatosis patients and reached an accuracy, analytical sensitivity and specificity greater than 99%, which was maintained in a validation set. I2HCP changed our diagnostic approach, involving clinicians and a genetic diagnostics team from panel design to reporting. The new strategy improved diagnostic sensitivity, solved uncertain clinical diagnoses and identified mutations in new genes. We assessed the genetic variation in the complete set of hereditary cancer genes, revealing a complex variation landscape that coexists with the disease-causing mutation. We developed, validated and implemented a custom NGS-based strategy for hereditary cancer diagnostics that improved our previous workflows. Additionally, the existence of a rich genetic variation in hereditary cancer genes favors the use of this panel to investigate their role in cancer risk.

Specialist perioperative allergy clinic services in the UK 2016: Results from the Royal College of Anaesthetists Sixth National Audit Project.

PubMed

Egner, W; Cook, T; Harper, N; Garcez, T; Marinho, S; Kong, K L; Nasser, S; Thomas, M; Warner, A; Hitchman, J; Floss, K

2017-10-01

Guidelines for investigation of perioperative drug allergy exist, but the quality of services is unknown. Specialist perioperative anaphylaxis services were surveyed through the Royal College of Anaesthetists 6 th National Audit Project. We compare self-declared UK practice in specialist perioperative allergy services with national recommendations. A SurveyMonkey™ questionnaire was distributed to providers of allergy services in the UK. Responses were assessed for adherence to the best practice recommendations of the British Society for Allergy and Clinical Immunology (BSACI), the Association of Anaesthetists of Great Britain and Ireland and the National Institute for Health and Care Excellence (NICE) Guidance on Drug Allergy-CG183. Over 1200 patients were evaluated in 44 centres annually. Variation in workload, waiting times, access, staffing and diagnostic approach was noted. Paediatric centres had the longest routine waiting times (most wait >13 weeks) in contrast to adult centres (most wait <12 weeks). Service leads are allergists/immunologists (91%) or anaesthetists (7%). Potentially important differences were seen in: testing repertoire [10/44 (23%) lacked BSACI compliant neuromuscular blocking agent (NMBA) panels and 17/44 (39%) lacked a NAP6-defined extended panel; many failed to screen all cases for chlorhexidine 19/44 (43%) or latex 21/44 (48%)], staffing [only 26/44 (59%) had specialist nurses and 18/44 (41%) an anaesthetist] and provision of information [18/44 (41%) gave immediate information in clinic and 5/44 (11%) sign-posted support groups]. Most centres were able to provide diagnostic challenges to antibiotics [40/44 (91%]) and local anaesthetics [41/44 (93%)]. Diagnostic testing is not harmonized, with marked variability in the NMBA panels used to identify safe alternatives. Chlorhexidine and latex are not part of routine testing in many centres. Poor access to services and patient information provision require attention. Harmonization of diagnostic approach is desirable, particularly with regard to a minimum NMBA panel for identification of safe alternatives. © 2017 John Wiley & Sons Ltd.

Doubling immunochemistry laboratory testing efficiency with the cobas e 801 module while maintaining consistency in analytical performance.

PubMed

Findeisen, P; Zahn, I; Fiedler, G M; Leichtle, A B; Wang, S; Soria, G; Johnson, P; Henzell, J; Hegel, J K; Bendavid, C; Collet, N; McGovern, M; Klopprogge, K

2018-06-04

The new immunochemistry cobas e 801 module (Roche Diagnostics) was developed to meet increasing demands on routine laboratories to further improve testing efficiency, while maintaining high quality and reliable data. During a non-interventional multicenter evaluation study, the overall performance, functionality and reliability of the new module was investigated under routine-like conditions. It was tested as a dedicated immunochemistry system at four sites and as a consolidator combined with clinical chemistry at three sites. We report on testing efficiency and analytical performance of the new module. Evaluation of sample workloads with site-specific routine request patterns demonstrated increased speed and almost doubled throughput (maximal 300 tests per h), thus revealing that one cobas e 801 module can replace two cobas e 602 modules while saving up to 44% floor space. Result stability was demonstrated by QC analysis per assay throughout the study. Precision testing over 21 days yielded excellent results within and between labs, and, method comparison performed versus the cobas e 602 module routine results showed high consistency of results for all assays under study. In a practicability assessment related to performance and handling, 99% of graded features met (44%) or even exceeded (55%) laboratory expectations, with enhanced reagent management and loading during operation being highlighted. By nearly doubling immunochemistry testing efficiency on the same footprint as a cobas e 602 module, the new module has a great potential to further consolidate and enhance laboratory testing while maintaining high quality analytical performance with Roche platforms. Copyright © 2018 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Hotspot mutations in cancer genes may be missed in routine diagnostics due to neighbouring sequence variants.

PubMed

Bartels, Stephan; Schipper, Elisa; Hasemeier, Britta; Kreipe, Hans; Lehmann, Ulrich

2018-05-27

The detection of hotspot mutations in key cancer genes is now an essential part of the diagnostic work-up in molecular pathology. Nearly all assays for mutation detection involve an amplification step. A second single nucleotide variant (SNV) on the same allele adjacent to a mutational hotspot can interfere with primer binding, leading to unnoticed allele-specific amplification of the wild type allele and thereby false-negative mutation testing. We present two diagnostic cases with false negative sequence results for JAK2 and SRSF2. In both cases mutations would have escaped detection if only one strand of DNA had been analysed. Because many commercially available diagnostic kits rely on the analysis of only one DNA strand they are prone to fail in cases like these. Detailed protocols and quality control measures to prevent corresponding pitfalls are presented. Copyright © 2017. Published by Elsevier Inc.

Diagnostic accuracy of refractometer and Brix refractometer to assess failure of passive transfer in calves: protocol for a systematic review and meta-analysis.

PubMed

Buczinski, S; Fecteau, G; Chigerwe, M; Vandeweerd, J M

2016-06-01

Calves are highly dependent of colostrum (and antibody) intake because they are born agammaglobulinemic. The transfer of passive immunity in calves can be assessed directly by dosing immunoglobulin G (IgG) or by refractometry or Brix refractometry. The latter are easier to perform routinely in the field. This paper presents a protocol for a systematic review meta-analysis to assess the diagnostic accuracy of refractometry or Brix refractometry versus dosage of IgG as a reference standard test. With this review protocol we aim to be able to report refractometer and Brix refractometer accuracy in terms of sensitivity and specificity as well as to quantify the impact of any study characteristic on test accuracy.

High risk of false positive results in a widely used diagnostic test for detection of the porcine reproductive and respiratory syndrome virus (PRRSV).

PubMed

Fetzer, C; Pesch, S; Ohlinger, V F

2006-06-15

During 2003 and 2004, increasing numbers of positive PRRSV RT-PCR results were reported from herds negative for PRRSV infection. Interestingly, three herds represent nucleus herds with no animal contacts from outside and without clinical symptoms of PRRS until now. Since these positive results that were obtained using a PCR protocol adapted to routine laboratory conditions could not be reproduced with other PRRSV specific RT-PCRs, controlled negative and positive samples were used to examine this phenomenon. A RT-PCR assay for detection and differential diagnosis of the European and North American genotypes of the porcine reproductive and respiratory syndrome virus (PRRSV) according to the method previously published by Oleksiewicz et al. [Oleksiewicz, M.B., Botner, A., Madsen, K.G., Storgaard, T., 1998. Sensitive detection and typing of porcine reproductive and respiratory syndrome virus by RT-PCR amplification of whole viral genes. Vet. Microbiol. 64, 7-22] was investigated in parallel to another recently published method [Pesch, S., 2003. Etablierung einer Nachweismethode für die zwei Genotypen von dem porcine reproductive and respiratory syndrome virus (PRRSV) und ein Beitrag zu seiner molekularen Epidemiologie. Thesis, Institute of Virology, Faculty of Veterinary Medicine, University of Leipzig]. A panel of 228 clinical samples sent in for PRRSV routine diagnostics served as test panel. It was found that both methods have similar analytical sensitivity. However, the primers published by Oleksiewicz were shown to yield a very high proportion of false positive results under routine diagnostic laboratory conditions, i.e. they resulted in RT-PCR products with non-PRRSV sequences, that were indistinguishable from truly positive reagents in standard gel electrophoresis settings. The reason for and possible implications of this finding as well as the risk of modifying published methods without control are discussed.

Effectiveness of rapid prescreening and 10% rescreening in liquid-based Papanicolaou testing.

PubMed

Currens, Heather S; Nejkauf, Katharine; Wagner, Lynn; Raab, Stephen S

2012-01-01

Although rapid prescreening (RPS) has been shown to be an effective quality control procedure for detecting false-negative conventional Papanicolaou (Pap) tests, RPS has not been widely implemented in the United States. In our laboratory, cytotechnologists performed RPS in 3,567 liquid-based Pap tests: 1,911 SurePath (BD Diagnostics-TriPath, Burlington, NC) preparations that were manually screened and 1,656 ThinPrep Pap tests (Hologic, Bedford, MA) that were imaged using the ThinPrep Imaging System (Hologic). We compared the sensitivity of RPS, 10% rescreening (R-10%), and routine screening (RS). In contrast with previously published findings, we found that RS + RPS did not improve screening sensitivity compared with RS + R-10%. These results support the following hypotheses: (1) Higher baseline RS sensitivity as a result of Pap test diagnoses standardization implemented for quality improvement purposes decreases the performance impact of RPS. (2) R-10% and RPS quality assurance methods detect diagnostic failures caused by different types of cognitive errors.

Diagnostic laparoscopy should be performed before definitive resection for pancreatic cancer: a financial argument.

PubMed

Jayakrishnan, Thejus T; Nadeem, Hasan; Groeschl, Ryan T; George, Ben; Thomas, James P; Ritch, Paul S; Christians, Kathleen K; Tsai, Susan; Evans, Douglas B; Pappas, Sam G; Gamblin, T Clark; Turaga, Kiran K

2015-02-01

Laparoscopy is recommended to detect radiographically occult metastases in patients with pancreatic cancer before curative resection. This study was conducted to test the hypothesis that diagnostic laparoscopy (DL) is cost-effective in patients undergoing curative resection with or without neoadjuvant therapy (NAT). Decision tree modelling compared routine DL with exploratory laparotomy (ExLap) at the time of curative resection in resectable cancer treated with surgery first, (SF) and borderline resectable cancer treated with NAT. Costs (US$) from the payer's perspective, quality-adjusted life months (QALMs) and incremental cost-effectiveness ratios (ICERs) were calculated. Base case estimates and multi-way sensitivity analyses were performed. Willingness to pay (WtP) was US$4166/QALM (or US$50,000/quality-adjusted life year). Base case costs were US$34,921 for ExLap and US$33,442 for DL in SF patients, and US$39,633 for ExLap and US$39,713 for DL in NAT patients. Routine DL is the dominant (preferred) strategy in both treatment types: it allows for cost reductions of US$10,695/QALM in SF and US$4158/QALM in NAT patients. The present analysis supports the cost-effectiveness of routine DL before curative resection in pancreatic cancer patients treated with either SF or NAT. © 2014 International Hepato-Pancreato-Biliary Association.

Diagnosis of Dengue Infection Using Conventional and Biosensor Based Techniques

PubMed Central

Parkash, Om; Hanim Shueb, Rafidah

2015-01-01

Dengue is an arthropod-borne viral disease caused by four antigenically different serotypes of dengue virus. This disease is considered as a major public health concern around the world. Currently, there is no licensed vaccine or antiviral drug available for the prevention and treatment of dengue disease. Moreover, clinical features of dengue are indistinguishable from other infectious diseases such as malaria, chikungunya, rickettsia and leptospira. Therefore, prompt and accurate laboratory diagnostic test is urgently required for disease confirmation and patient triage. The traditional diagnostic techniques for the dengue virus are viral detection in cell culture, serological testing, and RNA amplification using reverse transcriptase PCR. This paper discusses the conventional laboratory methods used for the diagnosis of dengue during the acute and convalescent phase and highlights the advantages and limitations of these routine laboratory tests. Subsequently, the biosensor based assays developed using various transducers for the detection of dengue are also reviewed. PMID:26492265

Healthy individuals' perspectives on clinical research protocols and influences on enrollment decisions.

PubMed

Roberts, Laura Weiss; Kim, Jane Paik

2017-01-01

Understanding the perspectives of healthy individuals is important ethically and for the advancement of science. We assessed perceptions of risk associated with research procedures, comparing views of healthy individuals with and without experience in clinical research, and the respondents' reported willingness to volunteer. Semistructured interviews and written surveys were conducted. Study participants were healthy individuals, half of whom were currently enrolled in clinical research and half of whom had no prior experience in clinical research. Participants were queried regarding seven "minimal risk" or "greater than minimal risk" protocol vignettes with procedures of three types: routine diagnostic tests, more burdensome (i.e., more effort or potential harm) diagnostic tests, and pharmacologic interventions. Views of influences on enrollment decisions were also assessed. Most healthy individuals indicated that protocols with more burdensome or pharmacologic interventions were very risky (59%, 58%), as opposed to routine diagnostic test procedures (32%). Respondents' willingness to enroll in protocols varied by type of protocol (p value < .001) and was inversely correlated with risk assessments (regression coefficients from GEE = -0.4; -0.5; -0.7). The odds of healthy individuals with research experience expressing strong willingness to enroll in the depicted protocols were twice the odds of healthy individuals without research experience expressing the same level of willingness (OR = 2.0 95% CI: [1.1, 3.9]). Respondents did not assign risk categories as institutional review boards (IRBs) would, as indicated by low agreement (26%) between respondent and expert opinion on minimal risk protocols. Perceptions of procedure risk appear to influence healthy individuals' willingness to enroll in protocols. Participants with experience in clinical research were far more likely to express willingness to enroll, a finding with important scientific and ethical implications. The lack of alignment between healthy individuals' views of protocol risk and IRB categorization warrants further study.

Diagnostic pitfalls in newborns and babies with blisters and erosions.

PubMed

Nischler, Elke; Klausegger, Alfred; Hüttner, Clemens; Pohla-Gubo, Gabriele; Diem, Anja; Bauer, Johann W; Hintner, Helmut

2009-01-01

Establishing the correct diagnosis in newborns presenting with blisters and erosions is not always a straightforward process. Many different disease entities including acquired (i.e., infectious, immunobullous, traumatic) and inherited disorders have to be taken into consideration. Similarities in clinical appearance, colonization and/or superinfections of preexisting skin lesions, as well as the absence of late changes in the neonate often pose significant diagnostic challenges. In this paper we discuss by giving examples the process of making an accurate diagnosis of blistering skin diseases in the neonatal period on the basis of a diagnostic algorithm. In addition, we provide an overview of the rational use and the limitations of laboratory procedures such as microbial testing, routine light microscopy, immunofluorescence antigen mapping, transmission electron microscopy, and molecular genetic analysis.

Perendoscopic gastric pH determination. Simple method for increasing accuracy in diagnosing chronic atrophic gastritis.

PubMed

Farinati, F; Cardin, F; Di Mario, F; Sava, G A; Piccoli, A; Costa, F; Penon, G; Naccarato, R

1987-08-01

The endoscopic diagnosis of chronic atrophic gastritis is often underestimated, and most of the procedures adopted to increase diagnostic accuracy are time consuming and complex. In this study, we evaluated the usefulness of the determination of gastric juice pH by means of litmus paper. Values obtained by this method correlate well with gastric acid secretory capacity as measured by gastric acid analysis (r = -0.64, p less than 0.001) and are not affected by the presence of bile. Gastric juice pH determination increases sensitivity and other diagnostic parameters such as performance index (Youden J test), positive predictive value, and post-test probability difference by 50%. Furthermore, the negative predictive value is very high, the probability of missing a patient with chronic atrophic gastritis with this simple method being 2% for fundic and 15% for antral atrophic change. We conclude that gastric juice pH determination, which substantially increases diagnostic accuracy and is very simple to perform, should be routinely adopted.

Diagnostic validation of selected serological tests for detecting scrub typhus.

PubMed

Koraluru, Munegowda; Bairy, Indira; Varma, Muralidhar; Vidyasagar, Sudha

2015-07-01

Clinical diagnosis of scrub typhus is often difficult because the symptoms are very similar to those of other febrile illness such as dengue, leptospirosis, malaria and other viral hemorrhagic fevers. Though better diagnostic tests are available for rickettsial diseases and scrub typhus elsewhere, the Weil-Felix test is still commonly used in India, mainly because microimmunofluorescence assays (M-IFA) were not available in India till recently and relevant staff had insufficient training. The present study was performed to investigate the performance of M-IFA, IgM ELISA, and Weil-Felix test on 546 non-repeated serum samples from subjects suspected of having scrub typhus. One hundred and forty-three of these 546 samples were positive by M-IFA; these cases were also confirmed clinically to have scrub typhus based on their dramatic responses to doxycycline therapy. IgM ELISA was positive in 122 of the 143 M-IFA positive cases and the Weil-Felix test in 96. Though the Weil-Felix test is a heterophile agglutination test, it was found in this study to have good specificity but far too little sensitivity to use as a routine diagnostic test. IgM ELISA can be a good substitute for M-IFA. Incorporation of multiple prototype antigens on M-IFA slides is likely one of the reasons for its superior performance. As newer and better diagnostic assays become available for scrub typhus diagnosis in developed countries, it will be imperative to also use such tests in other endemic countries to prevent over- or under-diagnosis of scrub typhus. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

German translation, cross-cultural adaptation and diagnostic test accuracy of three frailty screening tools : PRISMA-7, FRAIL scale and Groningen Frailty Indicator.

PubMed

Braun, Tobias; Grüneberg, Christian; Thiel, Christian

2018-04-01

Routine screening for frailty could be used to timely identify older people with increased vulnerability und corresponding medical needs. The aim of this study was the translation and cross-cultural adaptation of the PRISMA-7 questionnaire, the FRAIL scale and the Groningen Frailty Indicator (GFI) into the German language as well as a preliminary analysis of the diagnostic test accuracy of these instruments used to screen for frailty. A diagnostic cross-sectional study was performed. The instrument translation into German followed a standardized process. Prefinal versions were clinically tested on older adults who gave structured in-depth feedback on the scales in order to compile a final revision of the German language scale versions. For the analysis of diagnostic test accuracy (criterion validity), PRISMA-7, FRAIL scale and GFI were considered the index tests. Two reference tests were applied to assess frailty, either based on Fried's model of a Physical Frailty Phenotype or on the model of deficit accumulation, expressed in a Frailty Index. Prefinal versions of the German translations of each instrument were produced and completed by 52 older participants (mean age: 73 ± 6 years). Some minor issues concerning comprehensibility and semantics of the scales were identified and resolved. Using the Physical Frailty Phenotype (frailty prevalence: 4%) criteria as a reference standard, the accuracy of the instruments was excellent (area under the curve AUC >0.90). Taking the Frailty Index (frailty prevalence: 23%) as the reference standard, the accuracy was good (AUC between 0.73 and 0.88). German language versions of PRISMA-7, FRAIL scale and GFI have been established and preliminary results indicate sufficient diagnostic test accuracy that needs to be further established.

Comparison of four diagnostic tests for the identification of serum antibodies in small ruminants infected with Mycoplasma agalactiae.

PubMed

Kittelberger, R; O'Keefe, J S; Meynell, R; Sewell, M; Rosati, S; Lambert, M; Dufour, P; Pépin, M

2006-02-01

To determine the diagnostic capability of a newly developed Western blot (WB) assay for the detection of serum antibodies against Mycoplasma agalactiae compared with conventional serological tests, and to identify the best test for routine diagnostic use. The serological test methods used were: two commercial indirect enzyme-linked immunosorbent assays (ELISA), viz ELISA-1, using a bacterial antigen preparation, and ELISA-2, using a recombinant protein (lipoprotein p48) antigen; the complement fixation test (CFT); and a newly developed WB assay, the latter both using a bacterial antigen preparation. Thirty sera from goats infected with M. agalactiae and 97 sera from non-infected sheep were tested using all four methods. Staining patterns in the WB were quite variable. An immuno-dominant band of 41 kDa was detected in 63% of sera from infected animals. The same band also appeared, although mostly very weakly, in 10% of sera from non-infected animals. When suspicious or very weak reactors were omitted, the diagnostic sensitivity (DSE) and diagnostic specificity (DSP), respectively, for the four assays were: WB=56.7%, 97.9%; ELISA-1=76.7%, 99.0%; ELISA-2=56.7%, 100%; and CFT=40.0%, 94.8%. ELISA-1 performed best in this comparison. While the WB can be used, it did not have a technical advantage over the ELISA. The CFT should be discouraged as the primary screening method for contagious agalactia and should be replaced by ELISA-1. Results from this study confirm that serological test methods for contagious agalactia are useful for the detection of infected flocks but will not detect every individual infected animal.

Diagnostic Methods for Bile Acid Malabsorption in Clinical Practice

PubMed Central

Vijayvargiya, Priya; Camilleri, Michael; Shin, Andrea; Saenger, Amy

2013-01-01

Altered bile acid (BA) concentrations in the colon may cause diarrhea or constipation. BA malabsorption (BAM) accounts for >25% of patients with irritable bowel syndrome (IBS) with diarrhea and chronic diarrhea in Western countries. As BAM is increasingly recognized, proper diagnostic methods are desired in clinical practice to help direct the most effective treatment course for the chronic bowel dysfunction. This review appraises the methodology, advantages and disadvantages of 4 tools that directly measure BAM: 14C-glycocholate breath and stool test, 75Selenium HomotauroCholic Acid Test (SeHCAT), 7 α-hydroxy-4-cholesten-3-one (C4) and fecal BAs. 14C-glycocholate is a laborious test no longer widely utilized. 75SeHCAT is validated, but not available in the United States. Serum C4 is a simple, accurate method that is applicable to a majority of patients, but requires further clinical validation. Fecal measurements to quantify total and individual fecal BAs are technically cumbersome and not widely available. Regrettably, none of these tests are routinely available in the U.S., and a therapeutic trial with a BA binder is used as a surrogate for diagnosis of BAM. Recent data suggest there is an advantage to studying fecal excretion of the individual BAs and their role in BAM; this may constitute a significant advantage of the fecal BA method over the other tests. Fecal BA test could become a routine addition to fecal fat measurement in patients with unexplained diarrhea. In summary, availability determines the choice of test among C4, SeHCAT and fecal BA; more widespread availability of such tests would enhance clinical management of these patients. PMID:23644387

Large two-centre study into the prevalence of Mycoplasma genitalium and Trichomonas vaginalis in the Netherlands.

PubMed

de Jong, A S; Rahamat-Langendoen, J C; van Alphen, Ptw; Hilt, N; van Herk, Cmc; Pont, Sbeh; Melchers, Wjg; van de Bovenkamp, Jhb

2016-09-01

Mycoplasma genitalium and Trichomonas vaginalis are common sexually transmitted infections (STIs). In the Netherlands, testing for M. genitalium and T. vaginalis is not recommended for first-line STI screening. Recent reports about the increasing antimicrobial resistance in M. genitalium raise concern about the adequacy of current empirical treatment regimens. It is necessary to have insight in the prevalence of M. genitalium and T. vaginalis in order to evaluate current first-line STI screening and treatment protocols. During a five-month period, samples sent to two large medical microbiology diagnostic centres in the Netherlands for STI screening (Chlamydia trachomatis and Neisseria gonorrhoeae) were retrospectively tested for the prevalence of M. genitalium and T. vaginalis using the Diagenode S-DiaMGTV kit. A total of 1569 samples from 1188 unique patients (55.4% female) were tested. M. genitalium was the second most prevalent STI detected (4.5% of the patients), after C. trachomatis (8.3%). T. vaginalis was detected in 1.4% of the patients, comparable to the prevalence of N. gonorrhoeae (1.3%). Dual infections were only detected in a small number of patients (1.0%). Incorporation of M. genitalium into routine STI screening should be considered, because of its relatively high prevalence, the consequences of its detection for antibiotic treatment and because of the availability of easy-to-use molecular diagnostic tests. For T. vaginalis, routine screening may be considered, depending on local prevalence and (sub)population. © The Author(s) 2015.

Laparoscopic management and its outcomes in cases with nonpalpable testis.

PubMed

Erdoğan, Cankat; Bahadır, Berktuğ; Taşkınlar, Hakan; Naycı, Ali

2017-06-01

Diagnostic laparoscopy is the gold standard in the algorithm of nonpalpable testis. Testicular tissue is examined and treatment is planned accordingly. In this study we reviewed the place of diagnostic laparoscopy, and evaluated the results and effectiveness of laparoscopy in the diagnosis and management of nonpalpable testis. Children who had diagnostic laparoscopy for nonpalpable testes were included in the study. Physical examination results, ultrasonography (USG) reports, age at surgery, laparoscopic and inguinal exploration findings, surgical procedures, orchiopexy results, early and late-term complications were evaluated. Follow-up visits were performed at 3-month intervals for the first, at 6-month intervals for the 2. year, then at yearly intervals. Testicular size and location was evaluated by during control examination. Overall 58 boys, and 68 testes (26 left: 44.8%; 22 right: 37.9%, and 10 bilateral: 17.2%) were included in the study. Mean age at surgery was 5.5 years (10 months-17 years). Diagnostic value of USG was 15.7%. Diagnostic laparoscopy findings were as follows: Group 1: blind-ended vessels, n=7 (10.2%); Group 2: intraabdominal testes, n=8 (11.7%); Group 3: vas and vessels entering internal ring, n=53 (77.9%). Overall 43 testes underwent orchiopexy, which were normal (n=8) or hypoplastic (n=35). Mean follow-up period was 19 months (1-12 years), and on an average 7 visits were performed (5-14). On follow-up, 5 testes were normal-sized and located in the scrotum, while 4 testes were atrophic and underwent orchiectomy. Two testes were found in the inguinal canal and redo orchiopexy was performed. Control USG revealed reduced testicular blood supply and volume. Laparoscopic surgery is safe and effective in the management of nonpalpable testes. In the majority, routine use of diagnostic laparoscopy in the algorithma does not confer any additional contributions in many patients.

Impact of clinical awareness and diagnostic tests on the underdiagnosis of Clostridium difficile infection.

PubMed

Alcalá, L; Reigadas, E; Marín, M; Martín, A; Catalán, P; Bouza, E

2015-08-01

A multicenter study of Clostridium difficile infection (CDI) performed during 2008 in Spain revealed that two of every three episodes went undiagnosed or were misdiagnosed owing to nonsensitive diagnostic tests or lack of clinical suspicion and request. Since then, efforts have been made to improve the diagnostic tests used by laboratories and to increase the awareness of this disease among both clinicians and microbiologists. Our objective was to evaluate the impact of these efforts by assessing the current magnitude of underdiagnosis of CDI in Spain using two point-prevalence studies performed on one day each in January and July of 2013. A total of 111 Spanish laboratories selected all unformed stool specimens received for microbiological diagnosis on these days, and toxigenic culture was performed at a central reference laboratory. Toxigenic isolates were characterized both pheno- and genotypically. The reference laboratory detected 103 episodes of CDI in patients aged 2 years or more. Half (50.5 %) of the episodes were not diagnosed in the participating laboratories, owing to insensitive diagnostic tests (15.5 %) or the lack of clinical suspicion and request (35.0 %). The main ribotypes were 014, 078/126, 001/072, and 106. Ribotype 027 caused 2.9 % of all cases. Despite all the interventions undertaken, CDI remains a highly neglected disease because of the lack of sensitive diagnostic tests in some institutions and, especially, the absence of clinical suspicion, mainly in patients with community-associated CDI. Toxigenic C. difficile should be routinely sought in unformed stools sent for microbiological diagnosis, regardless of their origin.

First round of external quality assessment of dengue diagnostics in the WHO Western Pacific Region, 2013.

PubMed

Pok, Kwoon Yong; Squires, Raynal C; Tan, Li Kiang; Takasaki, Tomohiko; Abubakar, Sazaly; Hasebe, Futoshi; Partridge, Jeffrey; Lee, Chin Kei; Lo, Janice; Aaskov, John; Ng, Lee Ching; Konings, Frank

2015-01-01

Accurate laboratory testing is a critical component of dengue surveillance and control. The objective of this programme was to assess dengue diagnostic proficiency among national-level public health laboratories in the World Health Organization (WHO) Western Pacific Region. Nineteen national-level public health laboratories performed routine dengue diagnostic assays on a proficiency testing panel consisting of two modules: one containing commercial serum samples spiked with cultured dengue viruses for the detection of nucleic acid and non-structural protein 1 (NS1) (Module A) and one containing human serum samples for the detection of anti-dengue virus antibodies (Module B). A review of logistics arrangements was also conducted. All 16 laboratories testing Module A performed reverse transcriptase polymerase chain reaction (RT-PCR) for both RNA and serotype detection. Of these, 15 had correct results for RNA detection and all 16 correctly serotyped the viruses. All nine laboratories performing NS1 antigen detection obtained the correct results. Sixteen of the 18 laboratories using IgM assays in Module B obtained the correct results as did the 13 laboratories that performed IgG assays. Detection of ongoing/recent dengue virus infection by both molecular (RT-PCR) and serological methods (IgM) was available in 15/19 participating laboratories. This first round of external quality assessment of dengue diagnostics was successfully conducted in national-level public health laboratories in the WHO Western Pacific Region, revealing good proficiency in both molecular and serological testing. Further comprehensive diagnostic testing for dengue virus and other priority pathogens in the Region will be assessed during future rounds.

Trade-offs in Cervical Cancer Prevention: Balancing Benefits and Risks

PubMed Central

Stout, Natasha K.; Goldhaber-Fiebert, Jeremy D.; Ortendahl, Jesse D.; Goldie, Sue J.

2009-01-01

Background New screening and vaccination technologies will provide women with more options for cervical cancer prevention. Because the risk of cervical cancer diminishes with effective routine screening, women may wish to consider additional attributes, such as the likelihood of false-positive results and diagnostic procedures for mild abnormalities likely to resolve without intervention in their screening choices. Methods We used an empirically calibrated simulation model of cervical cancer in the United States to assess the benefits and potential risks associated with prevention strategies differing by primary screening test, triage test for abnormal results (cytologic testing, human papillomavirus [HPV] DNA test), and screening frequency. Outcomes included colposcopy referrals, cervical intraepithelial neoplasia (CIN) types 1 and 2 or 3, lifetime cancer risk, and quality-adjusted life expectancy. Results Across strategies, colposcopy referrals and diagnostic workups varied 3-fold, although diagnostic rates of CIN 2 or 3 were similar and 95% of positive screening test results were for mild abnormalities likely to resolve on their own. For a representative group of a thousand 20-year-old women undergoing triennial screening for 10 years, we expect 1038 colposcopy referrals (7 CIN 2 or 3 diagnoses) from combined cytologic and HPV DNA testing and fewer than 200 referrals (6–7 CIN 2 or 3 diagnoses) for strategies that use triage testing. Similarly, for a thousand 40-year-old women, combined cytologic and HPV DNA testing led to 489 referrals (9 CIN 2 or 3), whereas alternative strategies resulted in fewer than 150 referrals (7–8 CIN 2 or 3). Using cytologic testing followed by triage testing in younger women minimizes both diagnostic workups and positive HPV test results, whereas in older women diagnostic workups are minimized with HPV DNA testing followed by cytologic triage testing. Conclusions Clinically relevant information highlighting trade-offs among cervical cancer prevention strategies allows for inclusion of personal preferences into women’s decision making about screening and provides additional dimensions to the construction of clinical guidelines. PMID:18809815

Periprosthetic infection: where do we stand with regard to Gram stain?

PubMed

Ghanem, Elie; Ketonis, Constantinos; Restrepo, Camilo; Joshi, Ashish; Barrack, Robert; Parvizi, Javad

2009-02-01

One of the routinely used intraoperative tests for diagnosis of periprosthetic infection (PPI) is the Gram stain. It is not known if the result of this test can vary according to the type of joint affected or the number of specimen samples collected. We examined the role of this diagnostic test in a large cohort of patients from a single institution. A positive gram stain was defined as the visualization of bacterial cells or "many neutrophils" (> 5 per high-power field) in the smear. The sensitivity, specificity, and predictive values of each individual diagnostic arm of Gram stain were determined. Combinations were performed in series, which required both tests to be positive to confirm infection, and also in parallel, which necessitated both tests to be negative to rule out infection. The presence of organisms and "many" neutrophils on a Gram smear had high specificity (98-100%) and positive predictive value (89-100%) in both THA and TKA. The sensitivities (30-50%) and negative predictive values (70-79%) of the 2 tests were low for both joint types. When the 2 tests were combined in series, the specificity and positive predictive value were absolute (100%). The sensitivity and the negative predictive value improved for both THA and TKA (43-64% and 82%, respectively). Although the 2 diagnostic arms of Gram staining can be combined to achieve improved negative predictive value (82%), Gram stain continues to have little value in ruling out PPI. With the advances in the field of molecular biology, novel diagnostic modalities need to be designed that can replace these traditional and poor tests.

A genotype independent, full-genome reverse-transcription protocol for HCV genotyping and resistance testing.

PubMed

Walker, Andreas; Bergmann, Matthias; Camdereli, Jennifer; Kaiser, Rolf; Lübke, Nadine; Timm, Jörg

2017-06-01

HCV treatment options and cure rates have tremendously increased in the last decade. Although a pan-genotype HCV treatment has recently been approved, most DAA therapies are still genotype specific. Resistance-associated variants (RAVs) can limit the efficacy of DAA therapy and are associated with increased risk for therapy failure. With the approval of DAA regimens that recommend resistance testing prior to therapy, correct assessment of the genotype and testing for viruses with RAVs is clinically relevant. However, genotyping and resistance testing is generally done in costly and laborious separate reactions. The aim of the study was to establish a genotype-independent full-genome reverse transcription protocol to generate a template for both genotyping and resistance testing and to implement it into our routine diagnostic setup. The complete HCV genome was reverse transcribed with a pan-genotype primer binding at the 3'end of the viral RNA. This cDNA served as template for transcription of the genotyping amplicon in the core region as well as for the resistance testing of NS3, NS5A, and NS5B. With the established RT-protocol the HCV core region was successfully amplified and genotyped from 124 out of 125 (99.2%) HCV-positive samples. The amplification efficiency of RAV containing regions in NS3, NS5A, NS5B was 96.2%, 96.6% and 94.4%, respectively. We developed a method for HCV full-genome cDNA synthesis and implemented it into a routine diagnostic setup. This cDNA can be used as template for genotyping amplicons covering the core or NS5B region as well as for resistance testing amplicons in NS3, NS5A and NS5B. Copyright © 2017 Elsevier B.V. All rights reserved.

Iron status determination in pregnancy using the Thomas plot.

PubMed

Weyers, R; Coetzee, M J; Nel, M

2016-04-01

Physiological changes during pregnancy affect routine tests for iron deficiency. The reticulocyte haemoglobin equivalent (RET-He) and serum-soluble transferrin receptor (sTfR) assay are newer diagnostic parameters for the detection of iron deficiency, combined in the Thomas diagnostic plot. We used this plot to determine the iron status of pregnant women presenting for their first visit to an antenatal clinic in Bloemfontein, South Africa. Routine laboratory tests (serum ferritin, full blood count and C-reactive protein) and RET-He and sTfR were performed. The iron status was determined using the Thomas plot. For this study, 103 pregnant women were recruited. According to the Thomas plot, 72.8% of the participants had normal iron stores and erythropoiesis. Iron-deficient erythropoiesis was detected in 12.6%. A third of participants were anaemic. Serum ferritin showed excellent sensitivity but poor specificity for detecting depleted iron stores. HIV status had no influence on the iron status of the participants. Our findings reiterate that causes other than iron deficiency should be considered in anaemic individuals. When compared with the Thomas plot, a low serum ferritin is a sensitive but nonspecific indicator of iron deficiency. The Thomas plot may provide useful information to identify pregnant individuals in whom haematologic parameters indicate limited iron availability for erythropoiesis. © 2015 John Wiley & Sons Ltd.

Accuracy of the radioactive copper incorporation test in the diagnosis of Wilson disease.

PubMed

Członkowska, Anna; Rodo, Maria; Wierzchowska-Ciok, Agata; Smolinski, Lukasz; Litwin, Tomasz

2018-02-08

In Wilson disease (WD), copper accumulates in the liver and other tissues because of mutations in the ATP7B copper transporter gene. Early and effective anticopper treatment is crucial. However, routine diagnostic methods based on clinical findings, copper metabolism tests, liver biopsies and DNA analyses do not always provide a conclusive diagnosis. The aim was to evaluate radioactive copper incorporation as a diagnostic test. We included cases with a diagnosis of WD supported by radiocopper testing and later, when available, confirmed by DNA analysis. Incorporation of 64 Cu was measured at 2, 24 and 48 hours following intravenous injection. Diagnostic accuracy (area under the receiver operating characteristic curve [AUC]), sensitivity, specificity and predictive value were assessed for 24 hours/2 hours and 48 hours/2 hours 64 Cu ratios and compared with serum measurements of ceruloplasmin, copper, non-ceruloplasmin-bound copper and urinary 24-hours copper excretion. Patients having two pathogenic ATP7B mutations (homozygotes/compound heterozygotes) (n = 74) had significantly lower 24 hours/2 hours and 48 hours/2 hours 64 Cu ratios than heterozygote controls (n = 21) (mean 0.14 and 0.12 vs 0.49 and 0.63, respectively; both P < .001). Of note, 24 hours/2 hours and 48 hours/2 hours 64 Cu ratios had excellent diagnostic accuracy, with AUCs approaching 1, and only 24-hours urinary copper excretion displayed similar positive features. Other copper metabolism tests studied had lower accuracy, specificity and sensitivity. The radioactive copper test had excellent diagnostic accuracy and may be useful in the evaluation of new therapies aimed at restoring ATP7B function. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

More than just T₄: diagnostic testing for hyperthyroidism in cats.

PubMed

Peterson, Mark E

2013-09-01

In older cats presenting with clinical features of hyperthyroidism, confirmation of a diagnosis of thyroid disease is usually straightforward. However, the potential for false-negative and false-positive results exists with all thyroid function tests (especially in the context of routine screening of asymptomatic cats) and leads to clinical dilemmas. For example, a high serum T₄ value may be found in a cat that lacks clinical signs of hyperthyroidism, or hyperthyroidism may be suspected in a cat with normal total T₄ concentrations. To avoid unnecessary treatment and potentially adverse effects in a euthyroid cat, thyroid function tests must always be interpreted in the light of the cat's history, clinical signs, physical examination findings and other laboratory findings. In this article the author reviews the use of commonly recommended thyroid function tests, focusing on clinical scenarios that present diagnostic difficulties. In doing so, he draws on the veterinary and comparative literature, his own clinical experience, and data, unpublished to date, obtained from a series of 100 hyperthyroid cats consecutively diagnosed at his clinic.

The Diagnostic Value of the Clarke Sign in Assessing Chondromalacia Patella

PubMed Central

Doberstein, Scott T; Romeyn, Richard L; Reineke, David M

2008-01-01

Context: Various techniques have been described for assessing conditions that cause pain at the patellofemoral (PF) joint. The Clarke sign is one such test, but the diagnostic value of this test in assessing chondromalacia patella is unknown. Objective: To (1) investigate the diagnostic value of the Clarke sign in assessing the presence of chondromalacia patella using arthroscopic examination of the PF joint as the “gold standard,” and (2) provide a historical perspective of the Clarke sign as a clinical diagnostic test. Design: Validation study. Setting: All patients of one of the investigators who had knee pain or injuries unrelated to the patellofemoral joint and were scheduled for arthroscopic surgery were recruited for this study. Patients or Other Participants: A total of 106 otherwise healthy individuals with no history of patellofemoral pain or dysfunction volunteered. Main Outcome Measure(s): The Clarke sign was performed on the surgical knee by a single investigator in the clinic before surgery. A positive test was indicated by the presence of pain sufficient to prevent the patient from maintaining a quadriceps muscle contraction against manual resistance for longer than 2 seconds. The preoperative result was compared with visual evidence of chondromalacia patella during arthroscopy. Results: Sensitivity was 0.39, specificity was 0.67, likelihood ratio for a positive test was 1.18, likelihood ratio for a negative test was 0.91, positive predictive value was 0.25, and negative predictive value was 0.80. Conclusions: Diagnostic validity values for the use of the Clarke sign in assessing chondromalacia patella were unsatisfactory, supporting suggestions that it has poor diagnostic value as a clinical examination technique. Additionally, an extensive search of the available literature for the Clarke sign reveals multiple problems with the test, causing significant confusion for clinicians. Therefore, the use of the Clarke sign as a routine part of a knee examination is not beneficial, and its use should be discontinued. PMID:18345345

The diagnostic value of the Clarke sign in assessing chondromalacia patella.

PubMed

Doberstein, Scott T; Romeyn, Richard L; Reineke, David M

2008-01-01

Various techniques have been described for assessing conditions that cause pain at the patellofemoral (PF) joint. The Clarke sign is one such test, but the diagnostic value of this test in assessing chondromalacia patella is unknown. To (1) investigate the diagnostic value of the Clarke sign in assessing the presence of chondromalacia patella using arthroscopic examination of the PF joint as the "gold standard," and (2) provide a historical perspective of the Clarke sign as a clinical diagnostic test. Validation study. All patients of one of the investigators who had knee pain or injuries unrelated to the patellofemoral joint and were scheduled for arthroscopic surgery were recruited for this study. A total of 106 otherwise healthy individuals with no history of patellofemoral pain or dysfunction volunteered. The Clarke sign was performed on the surgical knee by a single investigator in the clinic before surgery. A positive test was indicated by the presence of pain sufficient to prevent the patient from maintaining a quadriceps muscle contraction against manual resistance for longer than 2 seconds. The preoperative result was compared with visual evidence of chondromalacia patella during arthroscopy. Sensitivity was 0.39, specificity was 0.67, likelihood ratio for a positive test was 1.18, likelihood ratio for a negative test was 0.91, positive predictive value was 0.25, and negative predictive value was 0.80. Diagnostic validity values for the use of the Clarke sign in assessing chondromalacia patella were unsatisfactory, supporting suggestions that it has poor diagnostic value as a clinical examination technique. Additionally, an extensive search of the available literature for the Clarke sign reveals multiple problems with the test, causing significant confusion for clinicians. Therefore, the use of the Clarke sign as a routine part of a knee examination is not beneficial, and its use should be discontinued.

Clinical Laboratories – Production Factories or Specialized Diagnostic Centers

PubMed Central

Tóth, Judit

2016-01-01

Since a large proportion of medical decisions are based on laboratory results, clinical laboratories should meet the increasing demand of clinicians and their patients. Huge central laboratories may process over 10 million tests annually; they act as production factories, measuring emergency and routine tests with sufficient speed and accuracy. At the same time, they also serve as specialized diagnostic centers where well-trained experts analyze and interpret special test results. It is essential to improve and constantly monitor this complex laboratory service, by several methods. Sample transport by pneumatic tube system, use of an advanced laboratory information system and point-of-care testing may result in decreased total turnaround time. The optimization of test ordering may result in a faster and more cost-effective laboratory service. Autovalidation can save time for laboratory specialists, when the analysis of more complex results requires their attention. Small teams of experts responsible for special diagnostic work, and their interpretative reporting according to predetermined principles, may help to minimize subjectivity of these special reports. Although laboratory investigations have become so diversely developed in the past decades, it is essential that the laboratory can provide accurate results relatively quickly, and that laboratory specialists can support the diagnosis and monitoring of patients by adequate interpretation of esoteric laboratory methods. PMID:27683528

Using routine diagnostic data as a method of surveillance of arboviral infection in travellers: a comparative analysis with a focus on dengue.

PubMed

Cleton, Natalie; Reusken, Chantal; Murk, Jean-Luc; de Jong, Menno; Reimerink, Johan; van der Eijk, Annemiek; Koopmans, Marion

2014-01-01

In a large part of the developing world, limited infectious disease surveillance is performed. In laboratory information management systems data on diagnostic requests is available and may be amenable to trend analyses. We explored this potential, using DENV diagnostic requests as a model. Test results and anonymised information provided by clinicians were received for 8942 patients from diagnostic centres in the Netherlands from January 2000 to May 2011. The data were evaluated for completeness of a predefined minimal dataset and trends in DENV positive results by travel destination. Population travel data were obtained from a commercial registry, and dengue case notification data by country from WHO DengueNet. Vaccination history was rarely reported (0.4%); travel destination was completed for 42% of requests; trends in diagnostic requests and IgM positive tests for this subset correlated to the WHO DENV notifications for the three main travel destinations, with some discrepancies. Additionally, this approach may provide information on disease outbreaks with other pathogens causing diseases clinically similar to DENV. PCR data proved to be insufficient for trend monitoring by country. This approach is not straightforward, but shows potential for use as a source of additional information for surveillance of disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

Saliva as a non-invasive diagnostic tool for inflammation and insulin-resistance

PubMed Central

Desai, Gauri S; Mathews, Suresh T

2014-01-01

Saliva has been progressively studied as a non-invasive and relatively stress-free diagnostic alternative to blood. Currently, saliva testing is used for clinical assessment of hormonal perturbations, detection of HIV antibodies, DNA analysis, alcohol screening, and drug testing. Recently, there has been increasing interest in evaluating the diagnostic potential of saliva in obesity, inflammation, and insulin-resistance. Current literature has demonstrated elevated levels of inflammatory biomarkers including C-reactive protein, tumor necrosis factor-α, interleukin-6, and interferon-γ in saliva of obese/overweight children and adults. Salivary antioxidant status has also been studied as a measure of oxidative stress in individuals with type 2 diabetes. Further, several studies have demonstrated correlations of salivary markers of stress and insulin resistance including cortisol, insulin, adiponectin, and resistin with serum concentrations. These findings suggest the potential diagnostic value of saliva in health screening and risk stratification studies, particularly in the pediatric population, with implications for inflammatory, metabolic and cardiovascular conditions. However, additional studies are required to standardize saliva collection and storage procedures, validate analytical techniques for biomarker detection, and establish reference ranges for routine clinical use. The purpose of this review is to summarize and evaluate recent advancements in using saliva as a diagnostic tool for inflammation and insulin-resistance. PMID:25512775

Thermal effects of diagnostic ultrasound in an anthropomorphic skull model.

PubMed

Vyskocil, E; Pfaffenberger, S; Kollmann, C; Gleiss, A; Nawratil, G; Kastl, S; Unger, E; Aumayr, K; Schuhfried, O; Huber, K; Wojta, J; Gottsauner-Wolf, M

2012-12-01

Exposure to diagnostic ultrasound (US) can significantly heat biological tissue although conventional routine examinations are regarded as safe. The risk of unwanted thermal effects increases with a high absorption coefficient and extended insonation time. Certain applications of transcranial diagnostic US (TC-US) require prolonged exposure. An anthropomorphic skull model (ASM) was developed to evaluate thermal effects induced by TC-US of different modalities. The objective was to determine whether prolonged continuous TC-US application results in potentially harmful temperature increases. The ASM consists of a human skull with tissue mimicking material and exhibits acoustic and anatomical characteristics of the human skull and brain. Experiments are performed with a diagnostic US device testing four different US modalities: Duplex PW (pulsed wave) Doppler, PW Doppler, color flow Doppler and B-mode. Temperature changes are recorded during 180 minutes of insonation. All measurements revealed significant temperature increases during insonation independent of the US modality. The maximum temperature elevation of + 5.25° C (p < 0.001) was observed on the surface of the skull exposed to duplex PW Doppler. At the bone-brain border a maximum temperature increae of + 2.01 °C (p < 0.001) was noted. Temperature increases within the brain were < 1.23 °C (p = 0.001). The highest values were registered using the duplex PW Doppler modality. TC-US induces significant local heating effects in an ASM. An application duration that extends routine clinical periods causes potentially harmful heating especially in tissue close to bone. TC-US elevates the temperature in the brain mimicking tissue but is not capable of producing harmful temperature increases during routine examinations. However, the risk of thermal injury in brain tissue increases significantly after an exposure time of > 2 hours. © Georg Thieme Verlag KG Stuttgart · New York.

Characteristics of Children and Adolescents Diagnosed with HIV By Targeted and Diagnostic Testing in a Children's Hospital Network.

PubMed

Gutman, Colleen K; Middlebrooks, Lauren S; Zmitrovich, April; Camacho-Gonzalez, Andres; Morris, Claudia R

2018-06-05

Across the United States (US), rates of new human immunodeficiency virus (HIV) diagnosis have declined 1 . Despite this, adolescents have experienced increases in HIV diagnosis rates 1,2 . It is estimated that half of adolescents are unaware of their diagnosis 1,3 and that, on average, they are infected with HIV for nearly 3 years prior to diagnosis 2 . The Centers for Disease Control and Prevention (CDC) recommends routine universal HIV screening for everyone over age 13 in healthcare settings. These recommendations have not been widely implemented in pediatrics 4,5 , where HIV testing is often offered only to select high-risk populations or as part of a diagnostic work-up. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Informed decision-making before changing to RDT: a comparison of microscopy, rapid diagnostic test and molecular techniques for the diagnosis and identification of malaria parasites in Kassala, eastern Sudan.

PubMed

Osman, Mamoun M M; Nour, Bakri Y M; Sedig, Mohamed F; De Bes, Laura; Babikir, Adil M; Mohamedani, Ahmed A; Mens, Petra F

2010-12-01

Rapid diagnostic tests (RDTs) are promoted for the diagnosis of malaria in many countries. The question arises whether laboratories where the current method of diagnosis is microscopy should also switch to RDT. This problem was studied in Kassala, Sudan where the issue of switching to RDT is under discussion. Two hundred and three blood samples were collected from febrile patients suspected of having malaria. These were subsequently analysed with microscopy, RDT (SD Bioline P.f/P.v) and PCR for the detection and identification of Plasmodium parasites. Malaria parasites were detected in 36 blood samples when examined microscopically, 54 (26.6%) samples were found positive for malaria parasites by RDT, and 44 samples were positive by PCR. Further analysis showed that the RDT used in our study resulted in a relatively high number of false positive samples. When microscopy was compared with PCR, an agreement of 96.1% and k = 0.88 (sensitivity 85.7% and specificity 100%) was found. However, when RDT was compared with PCR, an agreement of only 81.2 and k = 0.48 (sensitivity 69% and specificity 84%) was found. PCR has proven to be one of the most specific and sensitive diagnostic methods, particularly for malaria cases with low parasitaemia. However, this technique has limitations in its routine use under resource-limited conditions, such as our study location. At present, based on these results, microscopy remains the best option for routine diagnosis of malaria in Kassala, eastern Sudan. © 2010 Blackwell Publishing Ltd.

Comparison of microbiological diagnosis of urinary tract infection in young children by routine health service laboratories and a research laboratory: Diagnostic cohort study.

PubMed

Birnie, Kate; Hay, Alastair D; Wootton, Mandy; Howe, Robin; MacGowan, Alasdair; Whiting, Penny; Lawton, Michael; Delaney, Brendan; Downing, Harriet; Dudley, Jan; Hollingworth, William; Lisles, Catherine; Little, Paul; O'Brien, Kathryn; Pickles, Timothy; Rumsby, Kate; Thomas-Jones, Emma; Van der Voort, Judith; Waldron, Cherry-Ann; Harman, Kim; Hood, Kerenza; Butler, Christopher C; Sterne, Jonathan A C

2017-01-01

To compare the validity of diagnosis of urinary tract infection (UTI) through urine culture between samples processed in routine health service laboratories and those processed in a research laboratory. We conducted a prospective diagnostic cohort study in 4808 acutely ill children aged <5 years attending UK primary health care. UTI, defined as pure/predominant growth ≥105 CFU/mL of a uropathogen (the reference standard), was diagnosed at routine health service laboratories and a central research laboratory by culture of urine samples. We calculated areas under the receiver-operator curve (AUC) for UTI predicted by pre-specified symptoms, signs and dipstick test results (the "index test"), separately according to whether samples were obtained by clean catch or nappy (diaper) pads. 251 (5.2%) and 88 (1.8%) children were classified as UTI positive by health service and research laboratories respectively. Agreement between laboratories was moderate (kappa = 0.36; 95% confidence interval [CI] 0.29, 0.43), and better for clean catch (0.54; 0.45, 0.63) than nappy pad samples (0.20; 0.12, 0.28). In clean catch samples, the AUC was lower for health service laboratories (AUC = 0.75; 95% CI 0.69, 0.80) than the research laboratory (0.86; 0.79, 0.92). Values of AUC were lower in nappy pad samples (0.65 [0.61, 0.70] and 0.79 [0.70, 0.88] for health service and research laboratory positivity, respectively) than clean catch samples. The agreement of microbiological diagnosis of UTI comparing routine health service laboratories with a research laboratory was moderate for clean catch samples and poor for nappy pad samples and reliability is lower for nappy pad than for clean catch samples. Positive results from the research laboratory appear more likely to reflect real UTIs than those from routine health service laboratories, many of which (particularly from nappy pad samples) could be due to contamination. Health service laboratories should consider adopting procedures used in the research laboratory for paediatric urine samples. Primary care clinicians should try to obtain clean catch samples, even in very young children.

Pathogen Inactivating Properties and Increased Sensitivity in Molecular Diagnostics by PAXgene, a Novel Non-Crosslinking Tissue Fixative.

PubMed

Loibner, Martina; Buzina, Walter; Viertler, Christian; Groelz, Daniel; Hausleitner, Anja; Siaulyte, Gintare; Kufferath, Iris; Kölli, Bettina; Zatloukal, Kurt

2016-01-01

Requirements on tissue fixatives are getting more demanding as molecular analysis becomes increasingly relevant for routine diagnostics. Buffered formaldehyde in pathology laboratories for tissue fixation is known to cause chemical modifications of biomolecules which affect molecular testing. A novel non-crosslinking tissue preservation technology, PAXgene Tissue (PAXgene), was developed to preserve the integrity of nucleic acids in a comparable way to cryopreservation and also to preserve morphological features comparable to those of formalin fixed samples. Because of the excellent preservation of biomolecules by PAXgene we investigated its pathogen inactivation ability and biosafety in comparison to formalin by in-vitro testing of bacteria, human relevant fungi and human cytomegalovirus (CMV). Guidelines for testing disinfectants served as reference for inactivation assays. Furthermore, we tested the properties of PAXgene for detection of pathogens by PCR based assays. All microorganisms tested were similarly inactivated by PAXgene and formalin except Clostridium sporogenes, which remained viable in seven out of ten assays after PAXgene treatment and in three out of ten assays after formalin fixation. The findings suggest that similar biosafety measures can be applied for PAXgene and formalin fixed samples. Detection of pathogens in PCR-based diagnostics using two CMV assays resulted in a reduction of four to ten quantification cycles of PAXgene treated samples which is a remarkable increase of sensitivity. PAXgene fixation might be superior to formalin fixation when molecular diagnostics and highly sensitive detection of pathogens is required in parallel to morphology assessment.

Estimated cost per HIV infection diagnosed through routine HIV testing offered in acute general medical admission units and general practice settings in England.

PubMed

Ong, K J; Thornton, A C; Fisher, M; Hutt, R; Nicholson, S; Palfreeman, A; Perry, N; Stedman-Bryce, G; Wilkinson, P; Delpech, V; Nardone, A

2016-04-01

Following national guidelines to expand HIV testing in high-prevalence areas in England, a number of pilot studies were conducted in acute general medical admission units (ACUs) and general practices (GPs) to assess the feasibility and acceptability of testing in these settings. The aim of this study was to estimate the cost per HIV infection diagnosed through routine HIV testing in these settings. Resource use data from four 2009/2010 Department of Health pilot studies (two ACUs; two GPs) were analysed. Data from the pilots were validated and supplemented with information from other sources. We constructed possible scenarios to estimate the cost per test carried out through expanded HIV testing in ACUs and GPs, and the cost per diagnosis. In the pilots, cost per test ranged from £8.55 to £13.50, and offer time and patient uptake were 2 minutes and 90% in ACUs, and 5 minutes and 60% in GPs, respectively. In scenario analyses we fixed offer time, diagnostic test cost and uptake rate at 2 minutes, £6 and 80% for ACUs, and 5 minutes, £9.60 and 40% for GPs, respectively. The cost per new HIV diagnosis at a positivity of 2/1000 tests conducted was £3230 in ACUs and £7930 in GPs for tests performed by a Band 3 staff member, and £5940 in ACUs and £18 800 in GPs for tests performed by either hospital consultants or GPs. Expanded HIV testing may be more cost-efficient in ACUs than in GPs as a consequence of a shorter offer time, higher patient uptake, higher HIV positivity and lower diagnostic test costs. As cost per new HIV diagnosis reduces at higher HIV positivity, expanded HIV testing should be promoted in high HIV prevalence areas. © 2015 British HIV Association.

Concordance in diagnostic testing for respiratory pathogens of bighorn sheep

USGS Publications Warehouse

Walsh, Daniel P.; Cassirer, E. Frances; Bonds, Michael D.; Brown, Daniel R.; Edwards, William H.; Weiser, Glen C.; Drew, Mark L.; Briggs, Robert E.; Fox, Karen A.; Miller, Michael W.; Shanthalingam, Sudarvili; Srikumaran, Subramaniam; Besser, Thomas E.

2016-01-01

Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack of appropriate standardized commercial kits. Results of diagnostic testing may also be called into question when investigators report different etiologies for disease outbreaks, despite similar clinical and pathologic findings. To evaluate reliability of diagnostic testing for respiratory pathogens of bighorn sheep (Ovis canadensis), we conducted a series of ring tests across 6 laboratories routinely involved in detection of Mycoplasma ovipneumoniae, Pasteurellaceae, lktA (the Pasteurellaceae gene encoding leukotoxin), and 3 reference laboratories. Consistency of results for replicate samples within laboratories was high (median agreement = 1.0). Agreement between laboratories was high for polymerase chain reaction (PCR) detection of M. ovipneumoniae and culture isolation of Mannheimia spp. and Bibersteinia trehalosi(median agreement = 0.89–0.95, Kappa = 0.65–0.74), and lower for PCR detection of Mannheimiaspp. lktA (median agreement = 0.58, Kappa = 0.12). Most errors on defined status samples were false negatives, suggesting test sensitivity was a greater problem than specificity. However, tests for M. haemolytica and lktA yielded some false positive results. Despite differences in testing protocols, median agreement among laboratories and correct classification of controls for most agents was ≥0.80, meeting or exceeding the standard required by federal proficiency testing programs. This information is valuable for interpreting test results, laboratory quality assessments, and advancing diagnosis of respiratory disease in wild sheep. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Commentary: Reducing diagnostic errors: another role for checklists?

PubMed

Winters, Bradford D; Aswani, Monica S; Pronovost, Peter J

2011-03-01

Diagnostic errors are a widespread problem, although the true magnitude is unknown because they cannot currently be measured validly. These errors have received relatively little attention despite alarming estimates of associated harm and death. One promising intervention to reduce preventable harm is the checklist. This intervention has proven successful in aviation, in which situations are linear and deterministic (one alarm goes off and a checklist guides the flight crew to evaluate the cause). In health care, problems are multifactorial and complex. A checklist has been used to reduce central-line-associated bloodstream infections in intensive care units. Nevertheless, this checklist was incorporated in a culture-based safety program that engaged and changed behaviors and used robust measurement of infections to evaluate progress. In this issue, Ely and colleagues describe how three checklists could reduce the cognitive biases and mental shortcuts that underlie diagnostic errors, but point out that these tools still need to be tested. To be effective, they must reduce diagnostic errors (efficacy) and be routinely used in practice (effectiveness). Such tools must intuitively support how the human brain works, and under time pressures, clinicians rarely think in conditional probabilities when making decisions. To move forward, it is necessary to accurately measure diagnostic errors (which could come from mapping out the diagnostic process as the medication process has done and measuring errors at each step) and pilot test interventions such as these checklists to determine whether they work.

The diagnostic management of upper extremity deep vein thrombosis: A review of the literature.

PubMed

Kraaijpoel, Noémie; van Es, Nick; Porreca, Ettore; Büller, Harry R; Di Nisio, Marcello

2017-08-01

Upper extremity deep vein thrombosis (UEDVT) accounts for 4% to 10% of all cases of deep vein thrombosis. UEDVT may present with localized pain, erythema, and swelling of the arm, but may also be detected incidentally by diagnostic imaging tests performed for other reasons. Prompt and accurate diagnosis is crucial to prevent pulmonary embolism and long-term complications as the post-thrombotic syndrome of the arm. Unlike the diagnostic management of deep vein thrombosis (DVT) of the lower extremities, which is well established, the work-up of patients with clinically suspected UEDVT remains uncertain with limited evidence from studies of small size and poor methodological quality. Currently, only one prospective study evaluated the use of an algorithm, similar to the one used for DVT of the lower extremities, for the diagnostic workup of clinically suspected UEDVT. The algorithm combined clinical probability assessment, D-dimer testing and ultrasonography and appeared to safely and effectively exclude UEDVT. However, before recommending its use in routine clinical practice, external validation of this strategy and improvements of the efficiency are needed, especially in high-risk subgroups in whom the performance of the algorithm appeared to be suboptimal, such as hospitalized or cancer patients. In this review, we critically assess the accuracy and efficacy of current diagnostic tools and provide clinical guidance for the diagnostic management of clinically suspected UEDVT. Copyright © 2017 Elsevier Ltd. All rights reserved.

Laboratory Diagnostics Market in East Africa: A Survey of Test Types, Test Availability, and Test Prices in Kampala, Uganda.

PubMed

Schroeder, Lee F; Elbireer, Ali; Jackson, J Brooks; Amukele, Timothy K

2015-01-01

Diagnostic laboratory tests are routinely defined in terms of their sensitivity, specificity, and ease of use. But the actual clinical impact of a diagnostic test also depends on its availability and price. This is especially true in resource-limited settings such as sub-Saharan Africa. We present a first-of-its-kind report of diagnostic test types, availability, and prices in Kampala, Uganda. Test types (identity) and availability were based on menus and volumes obtained from clinical laboratories in late 2011 in Kampala using a standard questionnaire. As a measure of test availability, we used the Availability Index (AI). AI is the combined daily testing volumes of laboratories offering a given test, divided by the combined daily testing volumes of all laboratories in Kampala. Test prices were based on a sampling of prices collected in person and via telephone surveys in 2015. Test volumes and menus were obtained for 95% (907/954) of laboratories in Kampala city. These 907 laboratories offered 100 different test types. The ten most commonly offered tests in decreasing order were Malaria, HCG, HIV serology, Syphilis, Typhoid, Urinalysis, Brucellosis, Stool Analysis, Glucose, and ABO/Rh. In terms of AI, the 100 tests clustered into three groups: high (12 tests), moderate (33 tests), and minimal (55 tests) availability. 50% and 36% of overall availability was provided through private and public laboratories, respectively. Point-of-care laboratories contributed 35% to the AI of high availability tests, but only 6% to the AI of the other tests. The mean price of the most commonly offered test types was $2.62 (range $1.83-$3.46). One hundred different laboratory test types were in use in Kampala in late 2011. Both public and private laboratories were critical to test availability. The tests offered in point-of-care laboratories tended to be the most available tests. Prices of the most common tests ranged from $1.83-$3.46.

Antenatal screening for Down syndrome: a quantitative demonstration of the improvements over the past 20 years.

PubMed

Renshaw, Richard; Ellis, Katrina; Jacobs, Patricia; Morris, Joan

2013-10-01

Pregnant women who receive a high screening risk result for Down, Edwards or Patau syndrome are offered diagnostic tests that carry a procedure-related risk of miscarriage. This study quantifies the improvement in the screening tests by calculating the number of women who had such tests per syndrome diagnosis from 1991 to 2010. Routinely stored data on prenatal chorionic villus sampling (CVS) and amniocentesis samples performed from 1991 to 2010 from the Wessex Regional Genetics Laboratory in England were extracted from the laboratory database. The numbers of diagnostic tests performed per Down, Edwards or Patau syndrome diagnosis were calculated according to the type of diagnostic test, and were adjusted for maternal age and gestational age at diagnosis. A total of 32,345 CVSs and amniocenteses identified 872 diagnoses of Down syndrome and 328 of Edwards and Patau syndrome. In 1991, there were 46 (95%CI: 16-111) CVSs per syndrome diagnosis compared with five (95%CI: 4-7) in 2010. For amniocenteses, the number fell from 53 (37-78) to 15 (11-22). This analysis demonstrates the improvements in antenatal screening for Down syndrome that have been made over the past 20 years, resulting in a reduction in the number of women tested and thus in the number of foetal deaths attributable to the testing procedure.

The population impact of screening for Down syndrome: audit of 19 326 invasive diagnostic tests in England and Wales in 2008.

PubMed

Morris, Joan K; Waters, Jonathan J; de Souza, E

2012-06-01

Pregnant women who receive a high screening risk result for Down, Edwards or Patau syndrome are offered diagnostic tests that carry a risk of miscarriage. This study determined how many women had such tests per syndrome diagnosis. The number of tests per Down, Edwards or Patau syndrome diagnosis adjusted for maternal and gestational age at diagnosis was calculated using routine data from 18 (95%) cytogenetic laboratories in England and Wales in 2008. There were 19,326 tests that identified 1118 diagnoses of Down syndrome and 615 of Edwards and Patau syndromes. There were eight chorionic villus samplings (CVS) per syndrome diagnosis compared with 16 amniocenteses (gestational age adjusted). The lowest number of tests per diagnosis (three for CVSs and for amniocentesis) resulted from an abnormal ultrasound scan. Among pregnant women, 2.9% had an invasive diagnostic test. If a CVS and an amniocentesis increase the risk of a miscarriage by 1% and 0.5%, respectively, approximately one miscarriage for every 14 Down, Edwards or Patau syndrome diagnosis would have occurred. A simple measurement of the population impact of screening for Down syndrome can be calculated using data already collected. Annual estimates should be produced to monitor the national fetal anomaly screening programme. © 2012 John Wiley & Sons, Ltd. © 2012 John Wiley & Sons, Ltd.

Platelet proteomics: from discovery to diagnosis.

PubMed

Looße, Christina; Swieringa, Frauke; Heemskerk, Johan W M; Sickmann, Albert; Lorenz, Christin

2018-05-22

Platelets are the smallest cells within the circulating blood with key roles in physiological haemostasis and pathological thrombosis regulated by the onset of activating/inhibiting processes via receptor responses and signalling cascades. Areas covered: Proteomics as well as genomic approaches have been fundamental in identifying and quantifying potential targets for future diagnostic strategies in the prevention of bleeding and thrombosis, and uncovering the complexity of platelet functions in health and disease. In this article, we provide a critical overview on current functional tests used in diagnostics and the future perspectives for platelet proteomics in clinical applications. Expert commentary: Proteomics represents a valuable tool for the identification of patients with diverse platelet associated defects. In-depth validation of identified biomarkers, e.g. receptors, signalling proteins, post-translational modifications, in large cohorts is decisive for translation into routine clinical diagnostics.

SSME Post Test Diagnostic System: Systems Section

NASA Technical Reports Server (NTRS)

Bickmore, Timothy

1995-01-01

An assessment of engine and component health is routinely made after each test firing or flight firing of a Space Shuttle Main Engine (SSME). Currently, this health assessment is done by teams of engineers who manually review sensor data, performance data, and engine and component operating histories. Based on review of information from these various sources, an evaluation is made as to the health of each component of the SSME and the preparedness of the engine for another test or flight. The objective of this project - the SSME Post Test Diagnostic System (PTDS) - is to develop a computer program which automates the analysis of test data from the SSME in order to detect and diagnose anomalies. This report primarily covers work on the Systems Section of the PTDS, which automates the analyses performed by the systems/performance group at the Propulsion Branch of NASA Marshall Space Flight Center (MSFC). This group is responsible for assessing the overall health and performance of the engine, and detecting and diagnosing anomalies which involve multiple components (other groups are responsible for analyzing the behavior of specific components). The PTDS utilizes several advanced software technologies to perform its analyses. Raw test data is analyzed using signal processing routines which detect features in the data, such as spikes, shifts, peaks, and drifts. Component analyses are performed by expert systems, which use 'rules-of-thumb' obtained from interviews with the MSFC data analysts to detect and diagnose anomalies. The systems analysis is performed using case-based reasoning. Results of all analyses are stored in a relational database and displayed via an X-window-based graphical user interface which provides ranked lists of anomalies and observations by engine component, along with supporting data plots for each.

Exercise induced von Willebrand Factor release -- new model for routine endothelial testing.

PubMed

Balen, Sanja; Ruzić, Alen; Mirat, Jure; Persić, Viktor

2007-01-01

Endothelial dysfunction (ED) is actively involved in the mechanism of occurrence, development and progression of all the degrees of atherosclerosis. The established impact of ED on the progress and outcome of cardiovascular diseases, together with convincing indications of a possible successful therapeutic modification, necessitate the changeover of ED assessment from experimental to a routine practice. As there is no appropriate method for a clinical practice, scientists anticipate significant research efforts in the further development. Among numerous methods already available, von Willebrand Factor (vWF) stands out significantly. In accordance with the accepted leading diagnostic role of vWF baseline levels in the group of peripheral endothelial markers, and earlier scientific observations on the absence of its expected reactivation during physical exercise, we hypothesised this promising theory. We believe that a constant stronger release of vWF in endothelial cell injury leads to the exhaustion of its stores in Weibel-Palade bodies with the consequent absence of the expected rise of concentration during the exercise. Therefore, we hypothesised that ED could be exhaustible vWF endothelopathy and the exercise induced release of vWF a new, simple, safe and reliable test for the detection of ED and monitoring of the expected therapeutic effect. In order to have a final clinical usability of the proposed diagnostic model, it is necessary to test its reliability in different pathological and risk states, and establish susceptibility in therapeutic procedures. The correlation with invasive functional angiographic tests and the flow mediated dilatation test of peripheral arteries also needs to be validated. We expect the proposed test of vWF inducibility to find its place in clinical practice, i.e. in prevention, prediction and therapy of cardiovascular diseases.

Elevated human chorionic gonadotropin levels in patients with chronic kidney disease: Case series and review of literature.

PubMed

Soni, S; Menon, M C; Bhaskaran, M; Jhaveri, K D; Molmenti, E; Muoio, V

2013-11-01

Women are often subjected to serum human chorionic gonadotropin (HCG) testing prior to diagnostic and therapeutic interventions. A positive result leads to further testing to rule out pregnancy and avoid possible fetal teratogenicity. The impact of chronic kidney disease (CKD) on HCG testing has not been studied. We report a series of 5 women out of 62 with CKD, who had a positive HCG test on routine pre-transplant screening at a single transplant center. We analyzed their case records retrospectively. Despite aggressive investigation, their elevated HCG levels remained unexplained. The positive test contributed to delays in transplantation and increased overall cost of treatment.

Superior Diagnostic Performance of Malaria Rapid Diagnostic Tests as compared to Blood Smears in U.S. Clinical Practice

PubMed Central

Stauffer, William M.; Cartwright, Charles P.; Olson, Douglas; Juni, Billie Anne; Taylor, Charlotte M; Bowers, Susan H.; Hanson, Kevan L.; Rosenblatt, Jon E.; Boulware, David R.

2010-01-01

Background Approximately 4 million U.S. travelers to developing countries are ill enough to seek healthcare with 1,500 malaria cases reported in the U.S. annually. The diagnosis of malaria is frequently delayed due to the time to prepare malaria blood films and lack of technical expertise. An easy, reliable rapid diagnostic test (RDT) with high sensitivity and negative predictive value (NPV), particularly for Plasmodium falciparum, would be clinically useful. The study objective was to determine the diagnostic performance of the FDA-approved NOW® Malaria Test in comparison to traditional thick and thin blood smears for malaria diagnosis. Methods This prospective study tested 852 consecutive blood samples sent for thick and thin smears with blinded, malaria rapid tests at three hospital laboratories during 2003–2006. Polymerase chain reaction (PCR) verified positive tests and discordant results. Results Malaria occurred in 11% (95/852). The rapid test had superior performance than the standard Giemsa thick blood smear (P=.003). The rapid test’s sensitivity for all malaria was 97% (92/95) vs. 85% (81/95) by blood smear, and the RDT had superior NPV of 99.6% vs. 98.2% (P=.001). The P. falciparum performance was excellent with 100% rapid test sensitivity versus only 88% (65/74) by blood smear (P=.003). Conclusions This operational study demonstrates the FDA-approved rapid malaria test is superior to a single set of blood smears performed under routine U.S. clinical laboratory conditions. The most valuable clinical role of the RDT is in the rapid diagnosis or the exclusion of P. falciparum malaria, which is particularly useful in outpatient settings when evaluating febrile travelers. PMID:19686072

Evaluation of Elecsys Syphilis Assay for Routine and Blood Screening and Detection of Early Infection

PubMed Central

Kremastinou, J.; Polymerou, V.; Lavranos, D.; Aranda Arrufat, A.; Harwood, J.; Martínez Lorenzo, M. J.; Ng, K. P.; Queiros, L.; Vereb, I.

2016-01-01

Treponema pallidum infections can have severe complications if not diagnosed and treated at an early stage. Screening and diagnosis of syphilis require assays with high specificity and sensitivity. The Elecsys Syphilis assay is an automated treponemal immunoassay for the detection of antibodies against T. pallidum. The performance of this assay was investigated previously in a multicenter study. The current study expands on that evaluation in a variety of diagnostic settings and patient populations, at seven independent laboratories. The samples included routine diagnostic samples, blood donation samples, samples from patients with confirmed HIV infections, samples from living organ or bone marrow donors, and banked samples, including samples previously confirmed as syphilis positive. This study also investigated the seroconversion sensitivity of the assay. With a total of 1,965 syphilis-negative routine diagnostic samples and 5,792 syphilis-negative samples collected from blood donations, the Elecsys Syphilis assay had specificity values of 99.85% and 99.86%, respectively. With 333 samples previously identified as syphilis positive, the sensitivity was 100% regardless of disease stage. The assay also showed 100% sensitivity and specificity with samples from 69 patients coinfected with HIV. The Elecsys Syphilis assay detected infection in the same bleed or earlier, compared with comparator assays, in a set of sequential samples from a patient with primary syphilis. In archived serial blood samples collected from 14 patients with direct diagnoses of primary syphilis, the Elecsys Syphilis assay detected T. pallidum antibodies for 3 patients for whom antibodies were not detected with the Architect Syphilis TP assay, indicating a trend for earlier detection of infection, which may have the potential to shorten the time between infection and reactive screening test results. PMID:27358468

Accuracy of molecular diagnostics in pemphigus and bullous pemphigoid: comparison of commercial and modified mosaic indirect immunofluorescence tests as well as enzyme-linked immunosorbent assays.

PubMed

Gornowicz-Porowska, Justyna; Seraszek-Jaros, Agnieszka; Bowszyc-Dmochowska, Monika; Kaczmarek, Elżbieta; Pietkiewicz, Paweł; Bartkiewicz, Paweł; Dmochowski, Marian

2017-02-01

Pemphigus and bullous pemphigoid (BP) are identified by autoantibodies (abs) against desmoglein 1, 3 (DSG1/3) and BP180/BP230, respectively. A novel mosaic to indirect immunofluorescence (IIF) using purified BP180 recombinant proteins spotted on slide and transfected cells expressing BP230, DSG1, DSG3 is available. The commercial (IgG detection) and modified (IgG4 detection) mosaic for indirect immunofluorescence (IIFc - IIF commercial, IIFm - IIF modified) and IgG ELISAs were evaluated in pemphigus and bullous pemphigoid (BP) molecular diagnostics. To compare diagnostic accuracy of commercial (IgG detection) and modified (IgG4 detection) mosaic IIF assay and to examine the diagnostic value of ELISAs in relation to mosaic IIF in routine laboratory diagnostics of pemphigus and BP. Sera from 37 BP and 19 pemphigus patients were studied. Associations between tests were assessed using Fisher's exact test. There are associations between the positive/negative samples detected by IIFc with desmoglein1 (DSG1)/desmoglein3 (DSG3)/BP230 transfected cells and ELISAs and no association between anti-BP180 IgG detection by IIFc and ELISA. IIFm with DSG1 and DSG3 showed both 100% sensitivity and 100% and 78% specificity, respectively, and 100% and 83% positive predictive value in relation to IIFc. IIFm with BP230 had 87% specificity, 55% sensitivity, whereas IIFm with BP180 had a 100% sensitivity and 13% specificity in relation to IIFc. The IIFc with DSG1/DSG3/BP230 transfected cells, excluding BP180 spots, is an alternative method to ELISA in pemphigus/BP diagnostics. IgG4 antibodies, both pathogenically and diagnostically important, are inconsistently detectable with IIFm.

A WAO - ARIA - GA²LEN consensus document on molecular-based allergy diagnostics

PubMed Central

2013-01-01

Molecular-based allergy (MA) diagnostics is an approach used to map the allergen sensitization of a patient at a molecular level, using purified natural or recombinant allergenic molecules (allergen components) instead of allergen extracts. Since its introduction, MA diagnostics has increasingly entered routine care, with currently more than 130 allergenic molecules commercially available for in vitro specific IgE (sIgE) testing. MA diagnostics allows for an increased accuracy in allergy diagnosis and prognosis and plays an important role in three key aspects of allergy diagnosis: (1) resolving genuine versus cross-reactive sensitization in poly-sensitized patients, thereby improving the understanding of triggering allergens; (2) assessing, in selected cases, the risk of severe, systemic versus mild, local reactions in food allergy, thereby reducing unnecessary anxiety for the patient and the need for food challenge testing; and (3) identifying patients and triggering allergens for specific immunotherapy (SIT). Singleplex and multiplex measurement platforms are available for MA diagnostics. The Immuno-Solid phase Allergen Chip (ISAC) is the most comprehensive platform currently available, which involves a biochip technology to measure sIgE antibodies against more than one hundred allergenic molecules in a single assay. As the field of MA diagnostics advances, future work needs to focus on large-scale, population-based studies involving practical applications, elucidation and expansion of additional allergenic molecules, and support for appropriate test interpretation. With the rapidly expanding evidence-base for MA diagnosis, there is a need for allergists to keep abreast of the latest information. The aim of this consensus document is to provide a practical guide for the indications, determination, and interpretation of MA diagnostics for clinicians trained in allergology. PMID:24090398

A WAO - ARIA - GA²LEN consensus document on molecular-based allergy diagnostics.

PubMed

Canonica, Giorgio Walter; Ansotegui, Ignacio J; Pawankar, Ruby; Schmid-Grendelmeier, Peter; van Hage, Marianne; Baena-Cagnani, Carlos E; Melioli, Giovanni; Nunes, Carlos; Passalacqua, Giovanni; Rosenwasser, Lanny; Sampson, Hugh; Sastre, Joaquin; Bousquet, Jean; Zuberbier, Torsten

2013-10-03

Molecular-based allergy (MA) diagnostics is an approach used to map the allergen sensitization of a patient at a molecular level, using purified natural or recombinant allergenic molecules (allergen components) instead of allergen extracts. Since its introduction, MA diagnostics has increasingly entered routine care, with currently more than 130 allergenic molecules commercially available for in vitro specific IgE (sIgE) testing.MA diagnostics allows for an increased accuracy in allergy diagnosis and prognosis and plays an important role in three key aspects of allergy diagnosis: (1) resolving genuine versus cross-reactive sensitization in poly-sensitized patients, thereby improving the understanding of triggering allergens; (2) assessing, in selected cases, the risk of severe, systemic versus mild, local reactions in food allergy, thereby reducing unnecessary anxiety for the patient and the need for food challenge testing; and (3) identifying patients and triggering allergens for specific immunotherapy (SIT).Singleplex and multiplex measurement platforms are available for MA diagnostics. The Immuno-Solid phase Allergen Chip (ISAC) is the most comprehensive platform currently available, which involves a biochip technology to measure sIgE antibodies against more than one hundred allergenic molecules in a single assay. As the field of MA diagnostics advances, future work needs to focus on large-scale, population-based studies involving practical applications, elucidation and expansion of additional allergenic molecules, and support for appropriate test interpretation. With the rapidly expanding evidence-base for MA diagnosis, there is a need for allergists to keep abreast of the latest information. The aim of this consensus document is to provide a practical guide for the indications, determination, and interpretation of MA diagnostics for clinicians trained in allergology.

Audit of the autoantibody test, EarlyCDT®-lung, in 1600 patients: an evaluation of its performance in routine clinical practice.

PubMed

Jett, James R; Peek, Laura J; Fredericks, Lynn; Jewell, William; Pingleton, William W; Robertson, John F R

2014-01-01

EarlyCDT(®)-Lung may enhance detection of early stage lung cancer by aiding physicians in assessing high-risk patients through measurement of biological markers (i.e., autoantibodies). The test's performance characteristics in routine clinical practice were evaluated by auditing clinical outcomes of 1613 US patients deemed at high risk for lung cancer by their physician, who ordered the EarlyCDT-Lung test for their patient. Clinical outcomes for all 1613 patients who provided HIPAA authorization are reported. Clinical data were collected from each patient's treating physician. Pathology reports when available were reviewed for diagnostic classification. Staging was assessed on histology, otherwise on imaging. Six month follow-up for the positives/negatives was 99%/93%. Sixty-one patients (4%) were identified with lung cancer, 25 of whom tested positive by EarlyCDT-Lung (sensitivity=41%). A positive EarlyCDT-Lung test on the current panel was associated with a 5.4-fold increase in lung cancer incidence versus a negative. Importantly, 57% (8/14) of non-small cell lung cancers detected as positive (where stage was known) were stage I or II. EarlyCDT-Lung has been extensively tested and validated in case-control settings and has now been shown in this audit to perform in routine clinical practice as predicted. EarlyCDT-Lung may be a complementary tool to CT for detection of early lung cancer. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Assessing stakeholder perceptions of the acceptability and feasibility of national scale-up for a dual HIV/syphilis rapid diagnostic test in Malawi.

PubMed

Maddox, Brandy L Peterson; Wright, Shauntā S; Namadingo, Hazel; Bowen, Virginia B; Chipungu, Geoffrey A; Kamb, Mary L

2017-12-01

The WHO recommends pregnant women receive both HIV and syphilis testing at their first antenatal care visit, as untreated maternal infections can lead to severe, adverse pregnancy outcomes. One strategy for increasing testing for both HIV and syphilis is the use of point-of-care (rapid) diagnostic tests that are simple, proven effective and inexpensive. In Malawi, pregnant women routinely receive HIV testing, but only 10% are tested for syphilis at their first antenatal care visit. This evaluation explores stakeholder perceptions of a novel, dual HIV/syphilis rapid diagnostic test and potential barriers to national scale-up of the dual test in Malawi. During June and July 2015, we conducted 15 semistructured interviews with 25 healthcare workers, laboratorians, Ministry of Health leaders and partner agency representatives working in prevention of mother-to-child transmission in Malawi. We asked stakeholders about the importance of a dual rapid diagnostic test, concerns using and procuring the dual test and recommendations for national expansion. Stakeholders viewed the test favourably, citing the importance of a dual rapid test in preventing missed opportunities for syphilis diagnosis and treatment, improving infant outcomes and increasing syphilis testing coverage. Primary technical concerns were about the additional procedural steps needed to perform the test, the possibility that testers may not adhere to required waiting times before interpreting results and difficulty reading and interpreting test results. Stakeholders thought national scale-up would require demonstration of cost-savings, uniform coordination, revisions to testing guidelines and algorithms, training of testers and a reliable supply chain. Stakeholders largely support implementation of a dual HIV/syphilis rapid diagnostic test as a feasible alternative to current antenatal testing. Scale-up will require addressing perceived barriers; negotiating changes to existing algorithms and guidelines; and Ministry of Health approval and funding to support training of staff and procurement of supplies. © Article author(s) (or their employer(s) unless otherwise stated in the text of thearticle) 2017. All rights reserved. No commercial use is permitted unless otherwiseexpressly granted.

FSCATT: Angular Dependence and Filter Options.

DTIC Science & Technology

The input routines to the code have been completely rewritten to allow for a free-form input format. The input routines now provide self-consistency checks and diagnostics for the user’s edification .

Diagnosis of Growth Hormone Deficiency in Childhood

PubMed Central

Stanley, Takara

2012-01-01

Purpose of Review The diagnosis of growth hormone deficiency (GHD) in childhood is challenging, in large part due to the lack of a true gold standard and the relatively poor performance of available diagnostic testing. This review discusses recent literature on this topic. Recent Findings Auxology and clinical judgment remain the foundation for the diagnosis of GHD. Provocative GH testing is poorly reproducible, dependent on factors such as body composition and pubertal status, and further limited by significant variability among commercially available GH assays. Measurement of IGF-I and IGFBP-3 is not diagnostically useful in isolation but is helpful in combination with other diagnostic measures. Neuroimaging is also useful to inform diagnosis, as pituitary abnormalities suggest a higher likelihood of GHD persisting into adulthood. Although genetic testing is not routinely performed in the diagnosis of GHD at the present time, multiple recent reports raise the possibility that it may play a more important role in diagnosing GHD in the future. Summary Beyond physicians’ integrated assessment of auxology, clinical presentation, and bone age, current tools to diagnose GHD are sub-optimal. Recent literature emphasizes the need to reappraise our current practice and to consider new tools for diagnosis. PMID:22157400

Production of recombinant dengue non-structural 1 (NS1) proteins from clinical virus isolates.

PubMed

Yohan, Benediktus; Wardhani, Puspa; Aryati; Trimarsanto, Hidayat; Sasmono, R Tedjo

2017-01-01

Dengue is a febrile disease caused by infection of dengue virus (DENV). Early diagnosis of dengue infection is important for better management of the disease. The DENV Non-Structural Protein 1 (NS1) antigen has been routinely used for the early dengue detection. In dengue epidemic countries such as Indonesia, clinicians are increasingly relying on the NS1 detection for confirmation of dengue infection. Various NS1 diagnostic tests are commercially available, however different sensitivities and specificities were observed in various settings. This study was aimed to generate dengue NS1 recombinant protein for the development of dengue diagnostic tests. Four Indonesian DENV isolates were used as the source of the NS1 gene cloning, expression, and purification in bacterial expression system. Recombinant NS1 proteins were successfully purified and their antigenicities were assessed. Immunization of mice with recombinant proteins observed the immunogenicity of the NS1 protein. The generated recombinant proteins can be potentially used in the development of NS1 diagnostic test. With minimal modifications, this method can be used for producing NS1 recombinant proteins from isolates obtained from other geographical regions. Copyright © 2016 Elsevier Inc. All rights reserved.

Diagnostic laparoscopy should be performed before definitive resection for pancreatic cancer: a financial argument

PubMed Central

Jayakrishnan, Thejus T; Nadeem, Hasan; Groeschl, Ryan T; George, Ben; Thomas, James P; Ritch, Paul S; Christians, Kathleen K; Tsai, Susan; Evans, Douglas B; Pappas, Sam G; Gamblin, T Clark; Turaga, Kiran K

2015-01-01

Objectives Laparoscopy is recommended to detect radiographically occult metastases in patients with pancreatic cancer before curative resection. This study was conducted to test the hypothesis that diagnostic laparoscopy (DL) is cost-effective in patients undergoing curative resection with or without neoadjuvant therapy (NAT). Methods Decision tree modelling compared routine DL with exploratory laparotomy (ExLap) at the time of curative resection in resectable cancer treated with surgery first, (SF) and borderline resectable cancer treated with NAT. Costs (US$) from the payer's perspective, quality-adjusted life months (QALMs) and incremental cost-effectiveness ratios (ICERs) were calculated. Base case estimates and multi-way sensitivity analyses were performed. Willingness to pay (WtP) was US$4166/QALM (or US$50 000/quality-adjusted life year). Results Base case costs were US$34 921 for ExLap and US$33 442 for DL in SF patients, and US$39 633 for ExLap and US$39 713 for DL in NAT patients. Routine DL is the dominant (preferred) strategy in both treatment types: it allows for cost reductions of US$10 695/QALM in SF and US$4158/QALM in NAT patients. Conclusions The present analysis supports the cost-effectiveness of routine DL before curative resection in pancreatic cancer patients treated with either SF or NAT. PMID:25123702

The Phenomenology of the Diagnostic Process: A Primary Care-Based Survey.

PubMed

Donner-Banzhoff, Norbert; Seidel, Judith; Sikeler, Anna Maria; Bösner, Stefan; Vogelmeier, Maria; Westram, Anja; Feufel, Markus; Gaissmaier, Wolfgang; Wegwarth, Odette; Gigerenzer, Gerd

2017-01-01

While dichotomous tasks and related cognitive strategies have been extensively researched in cognitive psychology, little is known about how primary care practitioners (general practitioners [GPs]) approach ill-defined or polychotomous tasks and how valid or useful their strategies are. To investigate cognitive strategies used by GPs for making a diagnosis. In a cross-sectional study, we videotaped 282 consultations, irrespective of presenting complaint or final diagnosis. Reflective interviews were performed with GPs after each consultation. Recordings of consultations and GP interviews were transcribed verbatim and analyzed using a coding system that was based on published literature and systematically checked for reliability. In total, 134 consultations included 163 diagnostic episodes. Inductive foraging (i.e., the initial, patient-guided search) could be identified in 91% of consultations. It contributed an average 31% of cues obtained by the GP in 1 consultation. Triggered routines and descriptive questions occurred in 38% and 84% of consultations, respectively. GPs resorted to hypothesis testing, the hallmark of the hypothetico-deductive method, in only 39% of consultations. Video recordings and interviews presumably interfered with GPs' behavior and accounts. GPs might have pursued more hypotheses and collected more information than usual. The testing of specific disease hypotheses seems to play a lesser role than previously thought. Our data from real consultations suggest that GPs organize their search for information in a skillfully adapted way. Inductive foraging, triggered routines, descriptive questions, and hypotheses testing are essential building blocks to make a diagnosis in the generalist setting. © The Author(s) 2016.

Implementation and Quality Control of Lung Cancer EGFR Genetic Testing by MALDI-TOF Mass Spectrometry in Taiwan Clinical Practice

PubMed Central

Su, Kang-Yi; Kao, Jau-Tsuen; Ho, Bing-Ching; Chen, Hsuan-Yu; Chang, Gee-Cheng; Ho, Chao-Chi; Yu, Sung-Liang

2016-01-01

Molecular diagnostics in cancer pharmacogenomics is indispensable for making targeted therapy decisions especially in lung cancer. For routine clinical practice, the flexible testing platform and implemented quality system are important for failure rate and turnaround time (TAT) reduction. We established and validated the multiplex EGFR testing by MALDI-TOF MS according to ISO15189 regulation and CLIA recommendation in Taiwan. Totally 8,147 cases from Aug-2011 to Jul-2015 were assayed and statistical characteristics were reported. The intra-run precision of EGFR mutation frequency was CV 2.15% (L858R) and 2.77% (T790M); the inter-run precision was CV 3.50% (L858R) and 2.84% (T790M). Accuracy tests by consensus reference biomaterials showed 100% consistence with datasheet (public database). Both analytical sensitivity and specificity were 100% while taking Sanger sequencing as the gold-standard method for comparison. EGFR mutation frequency of peripheral blood mononuclear cell for reference range determination was 0.002 ± 0.016% (95% CI: 0.000–0.036) (L858R) and 0.292 ± 0.289% (95% CI: 0.000–0.871) (T790M). The average TAT was 4.5 working days and the failure rate was less than 0.1%. In conclusion, this study provides a comprehensive report of lung cancer EGFR mutation detection from platform establishment, method validation to clinical routine practice. It may be a reference model for molecular diagnostics in cancer pharmacogenomics. PMID:27480787

Performance of Rapid Diagnostic Tests for Imported Malaria in Clinical Practice: Results of a National Multicenter Study

PubMed Central

Houzé, Sandrine; Boutron, Isabelle; Marmorat, Anne; Dalichampt, Marie; Choquet, Christophe; Poilane, Isabelle; Godineau, Nadine; Le Guern, Anne-Sophie; Thellier, Marc; Broutier, Hélène; Fenneteau, Odile; Millet, Pascal; Dulucq, Stéphanie; Hubert, Véronique; Houzé, Pascal; Tubach, Florence; Le Bras, Jacques; Matheron, Sophie

2013-01-01

We compared the performance of four rapid diagnostic tests (RDTs) for imported malaria, and particularly Plasmodium falciparum infection, using thick and thin blood smears as the gold standard. All the tests are designed to detect at least one protein specific to P. falciparum ( Plasmodium histidine-rich protein 2 (PfHRP2) or Plasmodium LDH (PfLDH)) and one pan-Plasmodium protein (aldolase or Plasmodium LDH (pLDH)). 1,311 consecutive patients presenting to 9 French hospitals with suspected malaria were included in this prospective study between April 2006 and September 2008. Blood smears revealed malaria parasites in 374 cases (29%). For the diagnosis of P. falciparum infection, the three tests detecting PfHRP2 showed high and similar sensitivity (96%), positive predictive value (PPV) (90%) and negative predictive value (NPV) (98%). The PfLDH test showed lower sensitivity (83%) and NPV (80%), despite good PPV (98%). For the diagnosis of non-falciparum species, the PPV and NPV of tests targeting pLDH or aldolase were 94–99% and 52–64%, respectively. PfHRP2-based RDTs are thus an acceptable alternative to routine microscopy for diagnosing P. falciparum malaria. However, as malaria may be misdiagnosed with RDTs, all negative results must be confirmed by the reference diagnostic method when clinical, biological or other factors are highly suggestive of malaria. PMID:24098699

Periprosthetic infection: where do we stand with regard to Gram stain?

PubMed Central

Ghanem, Elie; Ketonis, Constantinos; Restrepo, Camilo; Joshi, Ashish; Barrack, Robert

2009-01-01

Background and purpose One of the routinely used intraoperative tests for diagnosis of periprosthetic infection (PPI) is the Gram stain. It is not known if the result of this test can vary according to the type of joint affected or the number of specimen samples collected. We examined the role of this diagnostic test in a large cohort of patients from a single institution. Materials and methods A positive gram stain was defined as the visualization of bacterial cells or “many neutrophils” (> 5 per high-power field) in the smear. The sensitivity, specificity, and predictive values of each individual diagnostic arm of Gram stain were determined. Combinations were performed in series, which required both tests to be positive to confirm infection, and also in parallel, which necessitated both tests to be negative to rule out infection. Results The presence of organisms and “many” neutrophils on a Gram smear had high specificity (98–100%) and positive predictive value (89–100%) in both THA and TKA. The sensitivities (30–50%) and negative predictive values (70–79%) of the 2 tests were low for both joint types. When the 2 tests were combined in series, the specificity and positive predictive value were absolute (100%). The sensitivity and the negative predictive value improved for both THA and TKA (43–64% and 82%, respectively). Interpretation Although the 2 diagnostic arms of Gram staining can be combined to achieve improved negative predictive value (82%), Gram stain continues to have little value in ruling out PPI. With the advances in the field of molecular biology, novel diagnostic modalities need to be designed that can replace these traditional and poor tests. PMID:19297787

Routine clinical heart examinations using SQUID magnetocardiography at University of Tsukuba Hospital

NASA Astrophysics Data System (ADS)

Inaba, T.; Nakazawa, Y.; Yoshida, K.; Kato, Y.; Hattori, A.; Kimura, T.; Hoshi, T.; Ishizu, T.; Seo, Y.; Sato, A.; Sekiguchi, Y.; Nogami, A.; Watanabe, S.; Horigome, H.; Kawakami, Y.; Aonuma, K.

2017-11-01

A 64-channel Nb-based DC-SQUID magnetocardiography (MCG) system was installed at the University of Tsukuba Hospital (UTH) in March 2007 after obtaining Japanese pharmaceutical approval and insurance reimbursement approval. In the period between 2008 and 2016, the total number of patients was 10 085. The heart diseases diagnosed in fetuses as well as adults are mainly atrial arrhythmia, abnormal repolarization, ventricular arrhythmia, and fetal arrhythmia. In most cases of insufficient diagnostic accuracy with electrocardiography, SQUID MCG precisely revealed these heart diseases as an abnormal electrical current distribution. Based on success in routine examinations, SQUID MCG is now an indispensable clinical instrument with diagnostic software tuned up during routine use at UTH.

Quality Assurance of Rapid Diagnostic Tests for Malaria in Routine Patient Care in Rural Tanzania

PubMed Central

McMorrow, Meredith L.; Masanja, M. Irene; Kahigwa, Elizeus; Abdulla, Salim M. K.; Kachur, S. Patrick

2010-01-01

Histidine-rich protein II (HRP2)-based malaria rapid diagnostic tests (RDTs) have shown high sensitivity and specificity for detecting Plasmodium falciparum malaria in a variety of study settings. However, RDTs are susceptible to heat and humidity and variation in individual performance, which may affect their use in field settings. We evaluated sensitivity and specificity of RDTs during routine use for malaria case management in peripheral health facilities. From December 2007 to October 2008, HRP2-based ParaHIT-f RDTs were introduced in 12 facilities without available microscopy in Rufiji District, Tanzania. Health workers received a single day of instruction on how to perform an RDT and thick blood smear. Job aids, Integrated Management of Childhood Illness guidelines, and national malaria treatment algorithms were reviewed. For quality assurance (QA), thick blood smears for reference microscopy were collected for 2 to 3 days per week from patients receiving RDTs; microscopy was not routinely performed at the health facilities. Slides were stained and read centrally within 72 hours of collection by a reference microscopist. When RDT and blood smear results were discordant, blood smears were read by additional reference microscopists blinded to earlier results. Facilities were supervised monthly by the district laboratory supervisor or a member of the study team. Ten thousand six hundred fifty (10,650) patients were tested with RDTs, and 51.5% (5,488/10,650) had a positive test result. Blood smear results were available for 3,914 patients, of whom 40.1% (1,577/3,914) were positive for P. falciparum malaria. Overall RDT sensitivity was 90.7% (range by facility 85.7–96.5%) and specificity was 73.5% (range 50.0–84.3%). Sensitivity increased with increasing parasite density. Successful implementation of RDTs was achieved in peripheral health facilities with adequate training and supervision. Quality assurance is essential to the adequate performance of any laboratory test. Centralized staining and reading of blood smears provided useful monitoring of RDT performance. However, this level of QA may not be sustainable nationwide. PMID:20065013

Indications for endoscopic third ventriculostomy in normal pressure hydrocephalus.

PubMed

Paidakakos, Nikolaos; Borgarello, S; Naddeo, M

2012-01-01

Controversies remain regarding the proper diagnostic studies and prediction of outcome in patients with normal pressure hydrocephalus (NPH), and their management remains controversial. We propose a preoperative assessment routine the aim of which is to correctly select NPH patients, and to differentiate between them in terms of surgical treatment, identifying probable endoscopic third ventriculostomy (ETV) responders. We prospectively considered a group of 44 patients with suspected NPH on the basis of clinical symptoms and neuroradiological evidence, who have undergone supplemental diagnostic testing (tap test, external lumbar drainage, cerebrospinal fluid outflow resistance [Rout] determination through lumbar and ventricular infusion test). All 44 of these patients were treated with either shunt procedures or ETV. To choose the kind of treatment (shunt or ETV), we evaluated the individual response during infusion tests. The efficacy of both surgical techniques was approximately 70%, with a significantly lower complication rate for ETV. We evaluated the correlation between the various tests and the postoperative outcomes both for shunting and for ETV. Rout proved useful for preoperative assessment and choice of treatment. In carefully selected patients, ETV had qualitative results similar to shunting, presenting significantly fewer complications.

Multicentre evaluation of a direct agglutination test prototype kit (DAT-LPC) for diagnosis of visceral leishmaniasis.

PubMed

Oliveira, E; Oliveira, D; Cardoso, F A; Barbosa, J R; Marcelino, A P; Dutra, T; Araujo, T; Fernandes, L; Duque, D; Rabello, A

2017-12-01

In this study, we assessed the sensitivity, specificity, and diagnostic accuracy of a previously developed direct agglutination test (DAT) using a freeze-dried antigen derived from Leishmania infantum promastigotes and composed in a prototype kit for visceral leishmaniasis (VL) diagnosis, named DAT-LPC. To evaluate DAT-LPC reproducibility, the kit was used to analyse 207 serum samples from VL patients and 80 serum samples from patients with other parasitic infections or healthy subjects in four laboratories from different public health institutions in Brazil. DAT-LPC showed sensitivity between 96·2 and 99·5% (P = 0·14), specificity ranging from 96·2 to 97·5% (P = 0·95), and diagnostic accuracy ranging from 96·5 to 99% (P = 0·34). The inter-laboratory reproducibility of qualitative results was classified as excellent (κ index: 0·94-0·97). The reproducibility of the end-titre results in relation to the reference laboratory, ranged from 31 to 85%. These results demonstrate an excellent performance of the DAT-LPC, and validate it for the diagnosis of VL that could replace the immunofluorescent antibody test as the routine diagnostic test in the Brazilian public health system.

Cost Effectiveness Analysis of Clinically Driven versus Routine Laboratory Monitoring of Antiretroviral Therapy in Uganda and Zimbabwe

PubMed Central

Medina Lara, Antonieta; Kigozi, Jesse; Amurwon, Jovita; Muchabaiwa, Lazarus; Nyanzi Wakaholi, Barbara; Mujica Mota, Ruben E.; Walker, A. Sarah; Kasirye, Ronnie; Ssali, Francis; Reid, Andrew; Grosskurth, Heiner; Babiker, Abdel G.; Kityo, Cissy; Katabira, Elly; Munderi, Paula; Mugyenyi, Peter; Hakim, James; Darbyshire, Janet; Gibb, Diana M.; Gilks, Charles F.

2012-01-01

Background Despite funding constraints for treatment programmes in Africa, the costs and economic consequences of routine laboratory monitoring for efficacy and toxicity of antiretroviral therapy (ART) have rarely been evaluated. Methods Cost-effectiveness analysis was conducted in the DART trial (ISRCTN13968779). Adults in Uganda/Zimbabwe starting ART were randomised to clinically-driven monitoring (CDM) or laboratory and clinical monitoring (LCM); individual patient data on healthcare resource utilisation and outcomes were valued with primary economic costs and utilities. Total costs of first/second-line ART, routine 12-weekly CD4 and biochemistry/haematology tests, additional diagnostic investigations, clinic visits, concomitant medications and hospitalisations were considered from the public healthcare sector perspective. A Markov model was used to extrapolate costs and benefits 20 years beyond the trial. Results 3316 (1660LCM;1656CDM) symptomatic, immunosuppressed ART-naive adults (median (IQR) age 37 (32,42); CD4 86 (31,139) cells/mm3) were followed for median 4.9 years. LCM had a mean 0.112 year (41 days) survival benefit at an additional mean cost of $765 [95%CI:685,845], translating into an adjusted incremental cost of $7386 [3277,dominated] per life-year gained and $7793 [4442,39179] per quality-adjusted life year gained. Routine toxicity tests were prominent cost-drivers and had no benefit. With 12-weekly CD4 monitoring from year 2 on ART, low-cost second-line ART, but without toxicity monitoring, CD4 test costs need to fall below $3.78 to become cost-effective (<3xper-capita GDP, following WHO benchmarks). CD4 monitoring at current costs as undertaken in DART was not cost-effective in the long-term. Conclusions There is no rationale for routine toxicity monitoring, which did not affect outcomes and was costly. Even though beneficial, there is little justification for routine 12-weekly CD4 monitoring of ART at current test costs in low-income African countries. CD4 monitoring, restricted to the second year on ART onwards, could be cost-effective with lower cost second-line therapy and development of a cheaper, ideally point-of-care, CD4 test. PMID:22545079

Missed diagnostic opportunities within South Africa's early infant diagnosis program, 2010-2015.

PubMed

Haeri Mazanderani, Ahmad; Moyo, Faith; Sherman, Gayle G

2017-01-01

Samples submitted for HIV PCR testing that fail to yield a positive or negative result represent missed diagnostic opportunities. We describe HIV PCR test rejections and indeterminate results, and the associated delay in diagnosis, within South Africa's early infant diagnosis (EID) program from 2010 to 2015. HIV PCR test data from January 2010 to December 2015 were extracted from the National Health Laboratory Service Corporate Data Warehouse, a central data repository of all registered test-sets within the public health sector in South Africa, by laboratory number, result, date, facility, and testing laboratory. Samples that failed to yield either a positive or negative result were categorized according to the rejection code on the laboratory information system, and descriptive analysis performed using Microsoft Excel. Delay in diagnosis was calculated for patients who had a missed diagnostic opportunity registered between January 2013 and December 2015 by means of a patient linking-algorithm employing demographic details. Between 2010 and 2015, 2 178 582 samples were registered for HIV PCR testing of which 6.2% (n = 134 339) failed to yield either a positive or negative result, decreasing proportionally from 7.0% (n = 20 556) in 2010 to 4.4% (n = 21 388) in 2015 (p<0.001). Amongst 76 972 coded missed diagnostic opportunities, 49 585 (64.4%) were a result of pre-analytical error and 27 387 (35.6%) analytical error. Amongst 49 694 patients searched for follow-up results, 16 895 (34.0%) had at least one subsequent HIV PCR test registered after a median of 29 days (IQR: 13-57), of which 8.4% tested positive compared with 3.6% of all samples submitted for the same period. Routine laboratory data provides the opportunity for near real-time surveillance and quality improvement within the EID program. Delay in diagnosis and wastage of resources associated with missed diagnostic opportunities must be addressed and infants actively followed-up as South Africa works towards elimination of mother-to-child transmission.

A UK NEQAS ICC and ISH multicentre study using the Kreatech Poseidon HER2 FISH probe: intersite variation can be rigorously controlled using FISH.

PubMed

Bartlett, John M S; Campbell, Fiona M; Ibrahim, Merdol; Thomas, Jeremy; Wencyk, Pete; Ellis, Ian; Kay, Elaine; Connolly, Yvonne; O'Grady, Anthony; Barnett, Sarah; Starczynski, Jane; Cunningham, Paul; Miller, Keith

2010-02-01

To assess a new HER2 fluorescence in situ hybridization (FISH) test and report on multicentre intrasite and intersite variation. HER2 results were scored from 45 breast cancers in eight laboratories using the Kreatech Poseidon HER2 FISH probe (Kreatech Diagnostics, Amsterdam, the Netherlands). Overall, 80.9% of cores were successfully analysed. Mean intrasite variation for HER2 ratio assessment was low (4.74%). Intersite variation in ratio was in line with previous reports (11.9+/-0.8%) for both reference and non-reference laboratories; only one laboratory displayed significantly higher intersite variation (P=0.009) than the remaining seven laboratories. The overall incidence of misclassification of cores was <1.3%, demonstrating an excellent level of concordance (>98.7%) across all eight laboratories, irrespective of whether they were 'reference' or 'routine diagnostic' laboratories. The Kreatech Poseidon HER2 FISH test is robust and reproducible. Highly quantitatively reproducible FISH results were obtained from eight 'diagnostic' and 'reference' laboratories; however, continued quality assessments are essential to good performance.

Recent Progress in the Development of Diagnostic Tests for Malaria.

PubMed

Krampa, Francis D; Aniweh, Yaw; Awandare, Gordon A; Kanyong, Prosper

2017-09-19

The impact of malaria on global health has continually prompted the need to develop effective diagnostic strategies. In malaria endemic regions, routine diagnosis is hampered by technical and infrastructural challenges to laboratories. These laboratories lack standard facilities, expertise or diagnostic supplies; thus, therapy is administered based on clinical or self-diagnosis. There is the need for accurate diagnosis of malaria due to the continuous increase in the cost of medication, and the emergence and spread of drug resistant strains. However, the widely utilized Giemsa-stained microscopy and immunochromatographic tests for malaria are liable to several drawbacks, including inadequate sensitivity and false-positive outcomes. Alternative methods that offer improvements in performance are either expensive, have longer turnaround time or require a level of expertise that makes them unsuitable for point-of-care (POC) applications. These gaps necessitate exploration of more efficient detection techniques with the potential of POC applications, especially in resource-limited settings. This minireview discusses some of the recent trends and new approaches that are seeking to improve the clinical diagnosis of malaria.

Evaluation of the NanoCHIP® Gastrointestinal Panel (GIP) Test for Simultaneous Detection of Parasitic and Bacterial Enteric Pathogens in Fecal Specimens

PubMed Central

Ken Dror, Shifra; Pavlotzky, Elsa; Barak, Mira

2016-01-01

Infectious gastroenteritis is a global health problem associated with high morbidity and mortality rates. Rapid and accurate diagnosis is crucial to allow appropriate and timely treatment. Current laboratory stool testing has a long turnaround time (TAT) and demands highly qualified personnel and multiple techniques. The need for high throughput and the number of possible enteric pathogens compels the implementation of a molecular approach which uses multiplex technology, without compromising performance requirements. In this work we evaluated the feasibility of the NanoCHIP® Gastrointestinal Panel (GIP) (Savyon Diagnostics, Ashdod, IL), a molecular microarray-based screening test, to be used in the routine workflow of our laboratory, a big outpatient microbiology laboratory. The NanoCHIP® GIP test provides simultaneous detection of nine major enteric bacteria and parasites: Campylobacter spp., Salmonella spp., Shigella spp., Giardia sp., Cryptosporidium spp., Entamoeba histolytica, Entamoeba dispar, Dientamoeba fragilis, and Blastocystis spp. The required high-throughput was obtained by the NanoCHIP® detection system together with the MagNA Pure 96 DNA purification system (Roche Diagnostics Ltd., Switzerland). This combined system has demonstrated a higher sensitivity and detection yield compared to the conventional methods in both, retrospective and prospective samples. The identification of multiple parasites and bacteria in a single test also enabled increased efficiency of detecting mixed infections, as well as reduced hands-on time and work load. In conclusion, the combination of these two automated systems is a proper response to the laboratory needs in terms of improving laboratory workflow, turn-around-time, minimizing human errors and can be efficiently integrated in the routine work of the laboratory. PMID:27447173

Diagnostic accuracy of patch test in children with food allergy.

PubMed

Caglayan Sozmen, Sule; Povesi Dascola, Carlotta; Gioia, Edoardo; Mastrorilli, Carla; Rizzuti, Laura; Caffarelli, Carlo

2015-08-01

The gold standard test for confirming whether a child has clinical hypersensitivity reactions to foods is the oral food challenge. Therefore, there is increasing interest in simpler diagnostic markers of food allergy, especially in children, to avoid oral food challenge. The goal of this study was to assess the diagnostic accuracy of atopy patch test in comparison with oral food challenge. We investigated 243 children (mean age, 51 months) referred for evaluation of suspected egg or cow's milk allergy. Skin prick test and atopy patch test were carried out, and after a 2 weeks elimination diet, oral food challenge was performed. Two hundred and forty-three children underwent OFC to the suspected food. We found clinically relevant food allergies in 40 (65%) children to egg and in 22 (35%) to cow's milk. The sensitivity of skin prick test for both milk and egg was 92%, specificity 91%, positive predictive value 35%, and negative predictive value of 93%. Sensitivity, specificity, positive predictive value, and negative predictive value of atopy patch test for both milk and egg were 21%, 73%, 20%, and 74%, respectively. Our study suggests that there is insufficient evidence for the routine use of atopy patch test for the evaluation of egg and cow's milk allergy. OFC remains gold standard for the diagnosis of egg and milk allergy even in the presence of high costs in terms of both time and risks during application. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Irregular analytical errors in diagnostic testing - a novel concept.

PubMed

Vogeser, Michael; Seger, Christoph

2018-02-23

In laboratory medicine, routine periodic analyses for internal and external quality control measurements interpreted by statistical methods are mandatory for batch clearance. Data analysis of these process-oriented measurements allows for insight into random analytical variation and systematic calibration bias over time. However, in such a setting, any individual sample is not under individual quality control. The quality control measurements act only at the batch level. Quantitative or qualitative data derived for many effects and interferences associated with an individual diagnostic sample can compromise any analyte. It is obvious that a process for a quality-control-sample-based approach of quality assurance is not sensitive to such errors. To address the potential causes and nature of such analytical interference in individual samples more systematically, we suggest the introduction of a new term called the irregular (individual) analytical error. Practically, this term can be applied in any analytical assay that is traceable to a reference measurement system. For an individual sample an irregular analytical error is defined as an inaccuracy (which is the deviation from a reference measurement procedure result) of a test result that is so high it cannot be explained by measurement uncertainty of the utilized routine assay operating within the accepted limitations of the associated process quality control measurements. The deviation can be defined as the linear combination of the process measurement uncertainty and the method bias for the reference measurement system. Such errors should be coined irregular analytical errors of the individual sample. The measurement result is compromised either by an irregular effect associated with the individual composition (matrix) of the sample or an individual single sample associated processing error in the analytical process. Currently, the availability of reference measurement procedures is still highly limited, but LC-isotope-dilution mass spectrometry methods are increasingly used for pre-market validation of routine diagnostic assays (these tests also involve substantial sets of clinical validation samples). Based on this definition/terminology, we list recognized causes of irregular analytical error as a risk catalog for clinical chemistry in this article. These issues include reproducible individual analytical errors (e.g. caused by anti-reagent antibodies) and non-reproducible, sporadic errors (e.g. errors due to incorrect pipetting volume due to air bubbles in a sample), which can both lead to inaccurate results and risks for patients.

Introducing malaria rapid diagnostic tests at registered drug shops in Uganda: limitations of diagnostic testing in the reality of diagnosis.

PubMed

Chandler, Clare I R; Hall-Clifford, Rachel; Asaph, Turinde; Pascal, Magnussen; Clarke, Siân; Mbonye, Anthony K

2011-03-01

In Uganda, around two thirds of medicines are procured from the private sector, mostly from drug shops. The introduction of malaria rapid diagnostic tests (RDTs) at drug shops therefore has the potential to make a significant contribution to targeting antimalarial drugs to those with malaria parasites. We undertook formative research in a district in Uganda in preparation for a randomised trial of RDTs in drug shops. In May to July 2009, we interviewed 9 drug shop workers, 5 health workers and 4 district health officials and carried out 10 focus group discussions with a total of 75 community members to investigate the role of drug shops and the potential for implementation of RDTs at these health care outlets. Drug shops were seen to provide an important service to community members, the nature of which is determined by responsiveness to client demands. However, drug shops hold a liminal status: in the eyes of different actors, these outlets are at once a shop and clinic; legitimate and illegitimate; and trusted and distrusted. Malaria treatment was found to be synonymous with diagnosis. Diagnostic testing was deemed useful in theory, and community members were curious about the results, with the expectation that a test would decrease uncertainty and help secure an end to illness. However, whether testing would be sought as a routine step in treatment decisions in practice is uncertain, since the appeal of the tests waned in light of their costs and potential for results to conflict with presumed diagnosis. Interventions that increase awareness of multiple causes and management of malaria-like illness will be needed to support the new rationalisation for malaria treatment represented by parasitological diagnosis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Introducing malaria rapid diagnostic tests at registered drug shops in Uganda: Limitations of diagnostic testing in the reality of diagnosis.

PubMed Central

Hall-Clifford, Rachel; Asaph, Turinde; Magnussen, Pascal; Clarke, Siân; Mbonye, Anthony K

2014-01-01

In Uganda, around two thirds of medicines are procured from the private sector, mostly from drug shops. The introduction of malaria rapid diagnostic tests (RDTs) at drug shops therefore has the potential to make a significant contribution to targeting antimalarial drugs to those with malaria parasites. We undertook formative research in a district in Uganda in preparation for a randomised trial of RDTs in drug shops. In May to July 2009, we interviewed 9 drug shop workers, 5 health workers and 4 district health officials and carried out 10 focus group discussions with a total of 75 community members to investigate the role of drug shops and the potential for implementation of RDTs at these health care outlets. Drug shops were seen to provide an important service to community members, the nature of which is determined by responsiveness to client demands. However, drug shops hold a liminal status: in the eyes of different actors, these outlets are at once a shop and clinic; legitimate and illegitimate; and trusted and distrusted. Malaria treatment was found to be synonymous with diagnosis. Diagnostic testing was deemed useful in theory, and community members were curious about the results, with the expectation that a test would decrease uncertainty and help secure an end to illness. However, whether testing would be sought as a routine step in treatment decisions in practice is uncertain, since the appeal of the tests waned in light of their costs and potential for results to conflict with presumed diagnosis. Interventions that increase awareness of multiple causes and management of malaria-like illness will be needed to support the new rationalisation for malaria treatment represented by parasitological diagnosis. PMID:21349623

[Human coronavirus infections: importance and diagnosis].

PubMed

Vabret, A; Brouard, J; Petitjean, J; Eugene-Ruellan, G; Freymuth, F

1998-11-14

POORLY-KNOWN VIRUS: Coronaviruses, so named because of their sun-ray-like aspect, were discovered in the sixties. The biology of these RNA viruses is complex and poorly understood. KNOWN PATHOGENS: Coronaviruses are known pathogens in veterinary medicine, causing disease states in several domestic species. In human medicine, they can cause benign respiratory infections, but few laboratories include coronaviruses in their routine diagnostic tests. SUSPECTED PATHOGENS: There is some data in the literature suggesting coronaviruses might be implicated in more severe diseases including multiple sclerosis, necrotizing enterocolitis, and lower respiratory tract infections, particularly in infants. IMPROVING DIAGNOSTIC METHODS: Due to the lack of reliable and sensitive diagnostic techniques, it is impossible to date to correctly assess the medical impact of these ubiquitous and endemic viruses. Molecular biology techniques enabling detection of human coronavirus infections should be applied to verifying the suspected implication of these viruses in diverse disease states.

Malaria, a difficult diagnosis in a febrile patient with sub-microscopic parasitaemia and polyclonal lymphocyte activation outside the endemic region, in Brazil

PubMed Central

2013-01-01

A case of autochthonous Plasmodium vivax malaria with sub-microscopic parasitaemia and polyclonal B-cell activation (PBA) (as reflected by positive IgM and IgG serology for toxoplasmosis, cytomegalovirus, and antinuclear and rheumatoid factors) was diagnosed by polymerase chain reaction (PCR) after consecutive negative rapid diagnostic test results and blood films. The patient, a 44-year-old man from Rio de Janeiro state, Brazil, had visited the Atlantic Forest, a tourist, non-malaria-endemic area where no autochthonous cases of ’bromeliad malaria‘ has ever been described. The characteristic pattern of fever, associated with PBA, was the clue to malaria diagnosis, despite consecutive negative thick blood smears. The study highlights a need for changes in clinical and laboratory diagnostic approaches, namely the incorporation of PCR as part of the current routine malaria diagnostic methods in non-endemic areas. PMID:24200365

Operational modelling: the mechanisms influencing TB diagnostic yield in an Xpert® MTB/RIF-based algorithm.

PubMed

Dunbar, R; Naidoo, P; Beyers, N; Langley, I

2017-04-01

Cape Town, South Africa. To compare the diagnostic yield for smear/culture and Xpert® MTB/RIF algorithms and to investigate the mechanisms influencing tuberculosis (TB) yield. We developed and validated an operational model of the TB diagnostic process, first with the smear/culture algorithm and then with the Xpert algorithm. We modelled scenarios by varying TB prevalence, adherence to diagnostic algorithms and human immunodeficiency virus (HIV) status. This enabled direct comparisons of diagnostic yield in the two algorithms to be made. Routine data showed that diagnostic yield had decreased over the period of the Xpert algorithm roll-out compared to the yield when the smear/culture algorithm was in place. However, modelling yield under identical conditions indicated a 13.3% increase in diagnostic yield from the Xpert algorithm compared to smear/culture. The model demonstrated that the extensive use of culture in the smear/culture algorithm and the decline in TB prevalence are the main factors contributing to not finding an increase in diagnostic yield in the routine data. We demonstrate the benefits of an operational model to determine the effect of scale-up of a new diagnostic algorithm, and recommend that policy makers use operational modelling to make appropriate decisions before new diagnostic algorithms are scaled up.

Utility of laboratory studies in seizures of children older than one month of age.

PubMed

Karbasi, S Akhavan; Mosadegh, M Modares; Fallah, R

2009-08-01

Seizure is the most common paediatric neurological disease which occurs in ten percent of children. In approaching a convulsive patient, finding the causes of seizure is essential, and the patient's history as well as the physical examination are important. The role of routine laboratory tests for children's seizures (except neonates) is undetermined, but checking for serum sodium, glucose, calcium and urea routinely has been advised. The purpose of this study was to determine the diagnostic efficacy of these serum chemistry tests in the seizures of children older than one month of age. In this descriptive, retrospective study, medical records of 302 hospitalised children with seizure were reviewed. Results of laboratory tests, like sodium, calcium, blood glucose and urea levels, pertinent history and physical examination, and the change in patient management based on serum chemistry test results, were analysed. All the children in the study were classified as having seizure with or without fever. In 302 hospitalised children with seizure, about ten percent of 938 tests were abnormal. 27.7 percent of these abnormal results were seen in 1-12-month-old infants. Only 11 percent of abnormal tests (1.3 percent of total tests) might have caused a seizure. Also, 0.2 percent of the results could not be predicted from the history or physical examination, which was conducted in patients younger than one year of age. Routine determination of serum chemistry values in seizures of children does not contribute to therapy, and are costly and time-consuming. It may not be helpful and informative unless the patient is less than one year of age.

Diagnosis of Bubonic Plague by PCR in Madagascar under Field Conditions

PubMed Central

Rahalison, L.; Vololonirina, E.; Ratsitorahina, M.; Chanteau, S.

2000-01-01

The diagnostic value of a PCR assay that amplifies a 501-bp fragment of the Yersinia pestis caf1 gene has been determined in a reference laboratory with 218 bubo aspirates collected from patients with clinically suspected plague managed in a regional hospital in Madagascar. The culture of Y. pestis and the detection of the F1 antigen (Ag) by enzyme-linked immunosorbent assay (ELISA) were used as reference diagnostic methods. The sensitivity of PCR was 89% (57 of 64) for the Y. pestis-positive patients, and 80.7% (63 of 78) for the F1 Ag-positive patients. The specificity of PCR for the culture-, F1 Ag-, and antibody-negative patients (n = 105) was 100%. Because in Madagascar most patients with plague are managed and their clinical samples are collected in remote villages, the usefulness of PCR was evaluated for routine diagnostic use in the operational conditions of the control program. The sensitivity of PCR was 50% (25 of 50) relative to the results of culture and 35.2% (19 of 54) relative to the results of the F1 Ag immunocapture ELISA. The specificity of PCR under these conditions was 96%. In conclusion, the PCR method was found to be very specific but not as sensitive as culture or the F1 Ag detection method. The limitation in sensitivity may have been due to suboptimal field conditions and the small volumes of samples used for DNA extraction. This technique is not recommended as a routine diagnostic test for plague in Madagascar. PMID:10618097

Diagnostic schemes for reducing epidemic size of African viral hemorrhagic fever outbreaks.

PubMed

Okeke, Iruka N; Manning, Robert S; Pfeiffer, Thomas

2014-09-12

Viral hemorrhagic fever (VHF) outbreaks, with high mortality rates, have often been amplified in African health institutions due to person-to-person transmission via infected body fluids.  By collating and analyzing epidemiological data from documented outbreaks, we observed that diagnostic delay contributes to epidemic size for Ebola and Marburg hemorrhagic fever outbreaks. We used a susceptible-exposed-infectious-removed (SEIR) model and data from the 1995 outbreak in Kikwit, Democratic Republic of Congo, to simulate Ebola hemorrhagic fever epidemics. Our model allows us to describe the dynamics for hospital staff separately from that for the general population, and to implement health worker-specific interventions. The model illustrates that implementing World Health Organization/US Centers for Disease Control and Prevention guidelines of isolating patients who do not respond to antimalarial and antibacterial chemotherapy reduces total outbreak size, from a median of 236, by 90% or more. Routinely employing diagnostic testing in post-mortems of patients that died of refractory fevers reduces the median outbreak size by a further 60%. Even greater reductions in outbreak size were seen when all febrile patients were tested for endemic infections or when febrile health-care workers were tested.  The effect of testing strategies was not impaired by the 1-3 day delay that would occur if testing were performed by a reference laboratory. In addition to improving the quality of care for common causes of febrile infections, increased and strategic use of laboratory diagnostics for fever could reduce the chance of hospital amplification of VHFs in resource-limited African health systems.

A Biodegradable Implant for Restoring Bone Discontinuity Defects in Dogs,

DTIC Science & Technology

1985-11-01

routine physical examinations and accepted veterinary diagnostic testing. Anesthesia All animals were kept NPO for 24 hours before surgery. Benzathine...procedure until the animal was responsive. After induc- tion of anesthesia with sodium pentothal (20 mg/kg, IV), animals were Intubated and maintained...at a surgical plane of anesthesia with 2 % halo- 4 5 1’ thane and N 20/0 2 50:50 (1 liter/min). Surgery Pre-extraction Resection Th- 𔃻, dng,, wore

[Clinical and electrophysiological findings in carpal tunnel syndrome].

PubMed

Kohara, Nobuo

2007-11-01

Carpal tunnel syndrome (CTS) is the most common nerve entrapment disorder. The clinical features of CTS are variable, but usually include pain and paresthesia in the thumb, first two fingers, and the radial-half of the ring finger. Paresthesia and sensory deficits might involve the entire palm area in some cases. Pain frequently radiate proximally into the forearm, and occasionally to the shoulder. Many patients experience pain at night and are awakened by abnormal sensations. Shaking hand relief the symptom. The two classic tests for nerve compression at the wrist are the Tinel test and the Phalen maneuver, which diagnostic value is limited. Golden standard for the diagnosis is the combination of the clinical findings and the electrophysiological study. Routine median nerve conduction study is valuable. Prolonged terminal latency of motor or sensory nerve would be found in most CTS hands. If the routine study showed equivocal, more sensitive methods are needed. Those include segmental sensory conduction study across the carpal tunnel by median stimulation at midpalm, a comparison of median and ulnar sensory nerve latencies at ring finger and a comparison of median and radial sensory nerve latencies at thumb. A difference between the median motor latency to the second lumbrical and the ulnar motor latency to the interossei muscles has also diagnostic value in some cases. In addition, inching method can localized the compression site. Using these techniques, the diagnosis of CTS would become more reliable.

Single-Center Experience with a Targeted Next Generation Sequencing Assay for Assessment of Relevant Somatic Alterations in Solid Tumors.

PubMed

Paasinen-Sohns, Aino; Koelzer, Viktor H; Frank, Angela; Schafroth, Julian; Gisler, Aline; Sachs, Melanie; Graber, Anne; Rothschild, Sacha I; Wicki, Andreas; Cathomas, Gieri; Mertz, Kirsten D

2017-03-01

Companion diagnostics rely on genomic testing of molecular alterations to enable effective cancer treatment. Here we report the clinical application and validation of the Oncomine Focus Assay (OFA), an integrated, commercially available next-generation sequencing (NGS) assay for the rapid and simultaneous detection of single nucleotide variants, short insertions and deletions, copy number variations, and gene rearrangements in 52 cancer genes with therapeutic relevance. Two independent patient cohorts were investigated to define the workflow, turnaround times, feasibility, and reliability of OFA targeted sequencing in clinical application and using archival material. Cohort I consisted of 59 diagnostic clinical samples from the daily routine submitted for molecular testing over a 4-month time period. Cohort II consisted of 39 archival melanoma samples that were up to 15years old. Libraries were prepared from isolated nucleic acids and sequenced on the Ion Torrent PGM sequencer. Sequencing datasets were analyzed using the Ion Reporter software. Genomic alterations were identified and validated by orthogonal conventional assays including pyrosequencing and immunohistochemistry. Sequencing results of both cohorts, including archival formalin-fixed, paraffin-embedded material stored up to 15years, were consistent with published variant frequencies. A concordance of 100% between established assays and OFA targeted NGS was observed. The OFA workflow enabled a turnaround of 3½ days. Taken together, OFA was found to be a convenient tool for fast, reliable, broadly applicable and cost-effective targeted NGS of tumor samples in routine diagnostics. Thus, OFA has strong potential to become an important asset for precision oncology. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Clonality analysis of lymphoid proliferations using the BIOMED-2 clonality assays: a single institution experience

PubMed Central

Kokovic, Ira; Novakovic, Barbara Jezersek; Cerkovnik, Petra; Novakovic, Srdjan

2014-01-01

Background Clonality determination in patients with lymphoproliferative disorders can improve the final diagnosis. The aim of our study was to evaluate the applicative value of standardized BIOMED-2 gene clonality assay protocols for the analysis of clonality of lymphocytes in a group of different lymphoid proliferations. Materials and methods. With this purpose, 121 specimens from 91 patients with suspected lymphoproliferations submitted for routine diagnostics from January to December 2011 were retrospectively analyzed. According to the final diagnosis, our series comprised 32 cases of B-cell lymphomas, 38 cases of non-Hodgkin’s T-cell lymphomas and 51 cases of reactive lymphoid proliferations. Clonality testing was performed using the BIOMED-2 clonality assays. Results The determined sensitivity of the TCR assay was 91.9%, while the sensitivity of the IGH assay was 74.2%. The determined specificity of the IGH assay was 73.3% in the group of lymphomas and 87.2% in the group of reactive lesions. The determined specificity of the TCR assay was 62.5% in the group of lymphomas and 54.3% in the group of reactive lesions. Conclusions In the present study, we confirmed the utility of standardized BIOMED-2 clonality assays for the detection of clonality in a routine diagnostical setting of non-Hodgkin’s lymphomas. Reactions for the detection of the complete IGH rearrangements and reactions for the detection of the TCR rearrangements are a good choice for clonality testing of a wide range of lymphoid proliferations and specimen types while the reactions for the detection of incomplete IGH rearrangements have not shown any additional diagnostic value. PMID:24991205

Laboratory diagnosis of gestational diabetes: An in silico investigation into the effects of pre-analytical processing on the diagnostic sensitivity and specificity of the oral glucose tolerance test.

PubMed

Mansell, Erin; Lunt, Helen; Docherty, Paul

2017-06-01

Delayed separation of red cells from plasma causes pre analytical glucose loss, which in turn results in an under-diagnosis of GDM (gestational diabetes) based on the OGTT (oral glucose tolerance test). In silico investigations may help laboratory decision making, when exploring pragmatic improvements to sample processing. Late pregnancy 0, 1 and 2h 75g OGTT values were obtained from two distinct populations of pregnant women: 1. Values derived from the HAPO (Hyperglycemia and Adverse Pregnancy Outcome) Study and 2. New Zealand women identified as at higher risk of GDM by their caregivers, undergoing OGTT during routine antenatal care. In both populations studied, in silico modelling focussed on the effects of pre-analytical delays in plasma separation, when using fluoride collection tubes. Using a model that 'batched' samples from the three OGTT collection times, diagnostic sensitivity was estimated as follows: 66.1% for HAPO research population and 48.4% for the 1305 women receiving routine antenatal care. If samples were not batched, but processed shortly after each blood sample was collected, then sensitivity increased to 81%. Exploration of a range of clinical and laboratory scenarios using in silico modelling, showed that delaying the processing of pregnancy OGTT samples, using batched sample collection into fluoride tubes, causes unacceptable loss of GDM diagnostic sensitivity across two distinct population groups. This modelling approach will hopefully provide information that helps with final decision making around improved laboratory processing techniques. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Placental growth factor (alone or in combination with soluble fms-like tyrosine kinase 1) as an aid to the assessment of women with suspected pre-eclampsia: systematic review and economic analysis.

PubMed

Frampton, Geoff K; Jones, Jeremy; Rose, Micah; Payne, Liz

2016-11-01

Pre-eclampsia (PE) prediction based on blood pressure, presence of protein in the urine, symptoms and laboratory test abnormalities can result in false-positive diagnoses. This may lead to unnecessary antenatal admissions and preterm delivery. Blood tests that measure placental growth factor (PlGF) or the ratio of soluble fms-like tyrosine kinase 1 (sFlt-1) to PlGF could aid prediction of PE if either were added to routine clinical assessment or used as a replacement for proteinuria testing. To evaluate the diagnostic accuracy and cost-effectiveness of PlGF-based tests for patients referred to secondary care with suspected PE in weeks 20-37 of pregnancy. Systematic reviews and an economic analysis. Bibliographic databases including MEDLINE, EMBASE, Web of Science and The Cochrane Library and Database of Abstracts of Reviews of Effects were searched up to July 2015 for English-language references. Conferences, websites, systematic reviews and confidential company submissions were also accessed. Systematic reviews of test accuracy and economic studies were conducted to inform an economic analysis. Test accuracy studies were required to include women with suspected PE and report quantitatively the accuracy of PlGF-based tests; their risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) criteria. The economic studies review had broad eligibility criteria to capture any types of economic analysis; critical appraisal employed standard checklists consistent with National Institute for Health and Care Excellence criteria. Study selection, critical appraisal and data extraction in both reviews were performed by two reviewers. An independent economic analysis was conducted based on a decision tree model, using the best evidence available. The model evaluates costs (2014, GBP) from a NHS and Personal Social Services perspective. Given the short analysis time horizon, no discounting was undertaken. Four studies were included in the systematic review of test accuracy: two on Alere's Triage ® PlGF test (Alere, Inc., San Diego, CA, USA) for predicting PE requiring delivery within a specified time and two on Roche Diagnostics' Elecsys ® sFlt-1 to PlGF ratio test (Roche Diagnostics GmbH, Mannheim, Germany) for predicting PE within a specified time. Three studies were included in the systematic review of economic studies, and two confidential company economic analyses were assessed separately. Study heterogeneity precluded meta-analyses of test accuracy or cost-analysis outcomes, so narrative syntheses were conducted to inform the independent economic model. The model predicts that, when supplementing routine clinical assessment for rule-out and rule-in of PE, the two tests would be cost-saving in weeks 20-35 of gestation, and marginally cost-saving in weeks 35-37, but with minuscule impact on quality of life. Length of neonatal intensive care unit stay was the most influential parameter in sensitivity analyses. All other sensitivity analyses had negligible effects on results. No head-to-head comparisons of the tests were identified. No studies investigated accuracy of PlGF-based tests when used as a replacement for proteinuria testing. Test accuracy studies were found to be at high risk of clinical review bias. The Triage and Elecsys tests would save money if added to routine clinical assessment for PE. The magnitude of savings is uncertain, but the tests remain cost-saving under worst-case assumptions. Further research is required to clarify how the test results would be interpreted and applied in clinical practice. This study is registered as PROSPERO CRD42015017670. The National Institute for Health Research Health Technology Assessment programme.

Increased use of malaria rapid diagnostic tests improves targeting of anti-malarial treatment in rural Tanzania: implications for nationwide rollout of malaria rapid diagnostic tests

PubMed Central

2012-01-01

Background The World Health Organization recommends parasitological confirmation of all malaria cases. Tanzania is implementing a phased rollout of malaria rapid diagnostic tests (RDTs) for routine use in all levels of care as one strategy to increase parasitological confirmation of malaria diagnosis. This study was carried out to evaluated artemisinin combination therapy (ACT) prescribing patterns in febrile patients with and without uncomplicated malaria in one pre-RDT implementation and one post-RDT implementation area. Methods A cross-sectional health facility surveys was conducted during high and low malaria transmission seasons in 2010 in both areas. Clinical information and a reference blood film on all patients presenting for an initial illness consultation were collected. Malaria was defined as a history of fever in the past 48 h and microscopically confirmed parasitaemia. Routine diagnostic testing was defined as RDT or microscopy ordered by the health worker and performed at the health facility as part of the health worker-patient consultation. Correct diagnostic testing was defined as febrile patient tested with RDT or microscopy. Over-testing was defined as a non-febrile patient tested with RDT or microscopy. Correct treatment was defined as patient with malaria prescribed ACT. Over-treatment was defined as patient without malaria prescribed ACT. Results A total of 1,247 febrile patients (627 from pre-implementation area and 620 from post-implementation area) were included in the analysis. In the post-RDT implementation area, 80.9% (95% CI, 68.2-89.3) of patients with malaria received recommended treatment with ACT compared to 70.3% (95% CI, 54.7-82.2) of patients in the pre-RDT implementation area. Correct treatment was significantly higher in the post-implementation area during high transmission season (85.9% (95%CI, 72.0-93.6) compared to 58.3% (95%CI, 39.4-75.1) in pre-implementation area (p = 0.01). Over-treatment with ACT of patients without malaria was less common in the post-RDT implementation area (20.9%; 95% CI, 14.7-28.8) compared to the pre-RDT implementation area (45.8%; 95% CI, 37.2-54.6) (p < 0.01) in high transmission. The odds of overtreatment was significantly lower in post- RDT area (adjusted Odds Ratio (OR: 95%CI) 0.57(0.36-0.89); and much higher with clinical diagnosis adjusted OR (95%CI) 2.24(1.37-3.67) Conclusion Implementation of RDTs increased use of RDTs for parasitological confirmation and reduced over-treatment with ACT during high malaria transmission season in one area in Tanzania. Continued monitoring of the national RDT rollout will be needed to assess whether these changes in case management practices will be replicated in other areas and sustained over time. Additional measures (such as refresher trainings, closer supervisions, etc.) may be needed to improve ACT targeting during low transmission seasons. PMID:22747655

Importance of including Blomia tropicalis in the routine diagnosis of Venezuelan patients with persistent allergic symptoms.

PubMed

Puccio, F A; Lynch, N R; Noya, O; Noga, O; Noda, A; Hagel, I; López, E; López, R; Caraballo, L; Mercado, D; DiPrisco, M C

2004-07-01

Blomia tropicalis is a common mite found in the house dust of many tropical countries including Venezuela. The prevalence of skin test and specific serum immunoglobulin (Ig)E reactivity to B. tropicalis in Venezuela has not been previously evaluated. In the present study we evaluated the skin reactivity by skin prick test and specific IgE by a multiple antigen blot assay, against B. tropicalis and Dermatophagoides pteronyssinus, in a group of 115 subjects who attended the Allergy Clinic of the Institute of Biomedicine, Caracas, Venezuela, and we studied possible cross reactions between similar proteins of these two mites. One hundred and six patients with persistent allergic respiratory symptoms showed a positive skin prick test to at least one of the mite extracts, with the frequency of positive reactions to B. tropicalis being as high as to D. pteronyssinus. Twelve patients reacted only to D. pteronyssinus and 13 different patients only to B. tropicalis. Specific IgE to each of the mite extracts was found with similar frequency, and the results coincided with the skin test reactivity. The study indicated the importance of including B. tropicalis in routine diagnostic testing in tropical and sub-tropical situations.

Measurement of hepatic functional mass by means of 13C-methacetin and 13C-phenylalanine breath tests in chronic liver disease: Comparison with Child-Pugh score and serum bile acid levels

PubMed Central

Festi, D.; Capodicasa, S.; Sandri, L.; Colaiocco-Ferrante, L.; Staniscia, T.; Vitacolonna, E.; Vestito, A.; Simoni, P.; Mazzella, G.; Portincasa, P.; Roda, E.; Colecchia, A.

2005-01-01

AIM: To evaluate and compare the clinical usefulness of 13C-phenylalanine and 13C-methacetin breath tests in quantitating functional hepatic mass in patients with chronic liver disease and to further compare these results with those of conventional tests, Child-Pugh score and serum bile acid levels. METHODS: One hundred and forty patients (50 HCV- related chronic hepatitis, 90 liver cirrhosis patients) and 40 matched healthy controls were studied. Both breath test and routine liver test, serum levels of cholic and chenodeoxycholic acid conjugates were evaluated. RESULTS: Methacetin breath test, expressed as 60 min cumulative percent of oxidation, discriminated the hepatic functional capacity not only between controls and liver disease patients, but also between different categories of chronic liver disease patients. Methacetin breath test was correlated with liver function tests and serum bile acids. Furthermore, methacetin breath test, as well as serum bile acids, were highly predictive of Child-Pugh scores. The diagnostic power of phenylalanine breath test was always less than that of methacetin breath test. CONCLUSION: Methacetin breath test represents a safe and accurate diagnostic tool in the evaluation of hepatic functional mass in chronic liver disease patients. PMID:15609414

The Relationship between Types of Attention and Auditory Processing Skills: Reconsidering Auditory Processing Disorder Diagnosis

PubMed Central

Stavrinos, Georgios; Iliadou, Vassiliki-Maria; Edwards, Lindsey; Sirimanna, Tony; Bamiou, Doris-Eva

2018-01-01

Measures of attention have been found to correlate with specific auditory processing tests in samples of children suspected of Auditory Processing Disorder (APD), but these relationships have not been adequately investigated. Despite evidence linking auditory attention and deficits/symptoms of APD, measures of attention are not routinely used in APD diagnostic protocols. The aim of the study was to examine the relationship between auditory and visual attention tests and auditory processing tests in children with APD and to assess whether a proposed diagnostic protocol for APD, including measures of attention, could provide useful information for APD management. A pilot study including 27 children, aged 7–11 years, referred for APD assessment was conducted. The validated test of everyday attention for children, with visual and auditory attention tasks, the listening in spatialized noise sentences test, the children's communication checklist questionnaire and tests from a standard APD diagnostic test battery were administered. Pearson's partial correlation analysis examining the relationship between these tests and Cochrane's Q test analysis comparing proportions of diagnosis under each proposed battery were conducted. Divided auditory and divided auditory-visual attention strongly correlated with the dichotic digits test, r = 0.68, p < 0.05, and r = 0.76, p = 0.01, respectively, in a sample of 20 children with APD diagnosis. The standard APD battery identified a larger proportion of participants as having APD, than an attention battery identified as having Attention Deficits (ADs). The proposed APD battery excluding AD cases did not have a significantly different diagnosis proportion than the standard APD battery. Finally, the newly proposed diagnostic battery, identifying an inattentive subtype of APD, identified five children who would have otherwise been considered not having ADs. The findings show that a subgroup of children with APD demonstrates underlying sustained and divided attention deficits. Attention deficits in children with APD appear to be centred around the auditory modality but further examination of types of attention in both modalities is required. Revising diagnostic criteria to incorporate attention tests and the inattentive type of APD in the test battery, provides additional useful data to clinicians to ensure careful interpretation of APD assessments. PMID:29441033

The rapid evolution of molecular genetic diagnostics in neuromuscular diseases.

PubMed

Volk, Alexander E; Kubisch, Christian

2017-10-01

The development of massively parallel sequencing (MPS) has revolutionized molecular genetic diagnostics in monogenic disorders. The present review gives a brief overview of different MPS-based approaches used in clinical diagnostics of neuromuscular disorders (NMDs) and highlights their advantages and limitations. MPS-based approaches like gene panel sequencing, (whole) exome sequencing, (whole) genome sequencing, and RNA sequencing have been used to identify the genetic cause in NMDs. Although gene panel sequencing has evolved as a standard test for heterogeneous diseases, it is still debated, mainly because of financial issues and unsolved problems of variant interpretation, whether genome sequencing (and to a lesser extent also exome sequencing) of single patients can already be regarded as routine diagnostics. However, it has been shown that the inclusion of parents and additional family members often leads to a substantial increase in the diagnostic yield in exome-wide/genome-wide MPS approaches. In addition, MPS-based RNA sequencing just enters the research and diagnostic scene. Next-generation sequencing increasingly enables the detection of the genetic cause in highly heterogeneous diseases like NMDs in an efficient and affordable way. Gene panel sequencing and family-based exome sequencing have been proven as potent and cost-efficient diagnostic tools. Although clinical validation and interpretation of genome sequencing is still challenging, diagnostic RNA sequencing represents a promising tool to bypass some hurdles of diagnostics using genomic DNA.

Pathogenesis and Management of Sarcopenia

PubMed Central

Dhillon, Robinder JS; Hasni, Sarfaraz

2016-01-01

SYNOPSIS Sarcopenia represents a loss of muscle strength and mass in older individuals and is a major determinant of fall risk and impaired ability to perform activities of daily living, often leading to disability, loss of independence and death. Sarcopenia in the elderly has now become a major focus of research and public policy debate due to its impact on morbidity, mortality and healthcare expenditure. Despite its clinical importance, sarcopenia remains under recognized and poorly managed in routine clinical practice. This is, in part, due to a lack of available diagnostic testing and uniform diagnostic criteria. The management of sarcopenia is primarily focused on physical therapy for muscle strengthening and gait training. There are no pharmacological agents currently approved for the treatment of sarcopenia. PMID:27886695

Performance of a real-time PCR assay in routine bovine mastitis diagnostics compared with in-depth conventional culture.

PubMed

Hiitiö, Heidi; Riva, Rauna; Autio, Tiina; Pohjanvirta, Tarja; Holopainen, Jani; Pyörälä, Satu; Pelkonen, Sinikka

2015-05-01

Reliable identification of the aetiological agent is crucial in mastitis diagnostics. Real-time PCR is a fast, automated tool for detecting the most common udder pathogens directly from milk. In this study aseptically taken quarter milk samples were analysed with a real-time PCR assay (Thermo Scientific PathoProof Mastitis Complete-12 Kit, Thermo Fisher Scientific Ltd.) and by semi-quantitative, in-depth bacteriological culture (BC). The aim of the study was to evaluate the diagnostic performance of the real-time PCR assay in routine use. A total of 294 quarter milk samples from routine mastitis cases were cultured in the national reference laboratory of Finland and examined with real-time PCR. With BC, 251 out of 294 (85.7%) of the milk samples had at least one colony on the plate and 38 samples were considered contaminated. In the PCR mastitis assay, DNA of target species was amplified in 244 samples out of 294 (83.0%). The most common bacterial species detected in the samples, irrespective of the diagnostic method, was the coagulase negative staphylococci (CNS) group (later referred as Staphylococcus spp.) followed by Staphylococcus aureus. Sensitivity (Se) and specificity (Sp) for the PCR assay to provide a positive Staph. aureus result was 97.0 and 95.8% compared with BC. For Staphylococcus spp., the corresponding figures were 86.7 and 75.4%. Our results imply that PCR performed well as a diagnostic tool to detect Staph. aureus but may be too nonspecific for Staphylococcus spp. in routine use with the current cut-off Ct value (37.0). Using PCR as the only microbiological method for mastitis diagnostics, clinical relevance of the results should be carefully considered before further decisions, for instance antimicrobial treatment, especially when minor pathogens with low amount of DNA have been detected. Introducing the concept of contaminated samples should also be considered.

Identification of Escherichia coli and Trueperella pyogenes isolated from the uterus of dairy cows using routine bacteriological testing and Fourier transform infrared spectroscopy.

PubMed

Jaureguiberry, María; Madoz, Laura Vanina; Giuliodori, Mauricio Javier; Wagener, Karen; Prunner, Isabella; Grunert, Tom; Ehling-Schulz, Monika; Drillich, Marc; de la Sota, Rodolfo Luzbel

2016-11-28

Uterine disorders are common postpartum diseases in dairy cows. In practice, uterine treatment is often based on systemic or locally applied antimicrobials with no previous identification of pathogens. Accurate on-farm diagnostics are not available, and routine testing is time-consuming and cost intensive. An accurate method that could simplify the identification of uterine pathogenic bacteria and improve pathogen-specific treatments could be an important advance to practitioners. The objective of the present study was to evaluate whether a database built with uterine bacteria from European dairy cows could be used to identify bacteria from Argentinean cows by Fourier transformed infrared (FTIR) spectroscopy. Uterine samples from 64 multiparous dairy cows with different types of vaginal discharge (VD) were collected between 5 and 60 days postpartum, analyzed by routine bacteriological testing methods and then re-evaluated by FTIR spectroscopy (n = 27). FTIR spectroscopy identified Escherichia coli in 12 out of 14 samples and Trueperella pyogenes in 8 out of 10 samples. The agreement between the two methods was good with a Kappa coefficient of 0.73. In addition, the likelihood for bacterial growth of common uterine pathogens such as E. coli and T. pyogenes tended to increase with VD score. The odds for a positive result to E. coli or T. pyogenes was 1.88 times higher in cows with fetid VD than in herdmates with clear normal VD. We conclude that the presence of E. coli and T. pyogenes in uterine samples from Argentinean dairy cows can be detected with FTIR with the use of a database built with uterine bacteria from European dairy cows. Future studies are needed to determine if FTIR can be used as an alternative to routine bacteriological testing methods.

EGFR T790M mutation testing of non-small cell lung cancer tissue and blood samples artificially spiked with circulating cell-free tumor DNA: results of a round robin trial.

PubMed

Fassunke, Jana; Ihle, Michaela Angelika; Lenze, Dido; Lehmann, Annika; Hummel, Michael; Vollbrecht, Claudia; Penzel, Roland; Volckmar, Anna-Lena; Stenzinger, Albrecht; Endris, Volker; Jung, Andreas; Lehmann, Ulrich; Zeugner, Silke; Baretton, Gustavo; Kreipe, Hans; Schirmacher, Peter; Kirchner, Thomas; Dietel, Manfred; Büttner, Reinhard; Merkelbach-Bruse, Sabine

2017-10-01

The European Commision (EC) recently approved osimertinib for the treatment of adult patients with locally advanced or metastatic non-small-cell lung cancer (NSCLC) harboring EGFR T790M mutations. Besides tissue-based testing, blood samples containing cell-free circulating tumor DNA (ctDNA) can be used to interrogate T790M status. Herein, we describe the conditions and results of a round robin trial (RRT) for T790M mutation testing in NSCLC tissue specimens and peripheral blood samples spiked with cell line DNA mimicking tumor-derived ctDNA. The underlying objectives of this two-staged external quality assessment (EQA) approach were (a) to evaluate the accuracy of T790M mutations testing across multiple centers and (b) to investigate if a liquid biopsy-based testing for T790M mutations in spiked blood samples is feasible in routine diagnostic. Based on a successfully completed internal phase I RRT, an open RRT for EGFR T790M mutation testing in tumor tissue and blood samples was initiated. In total, 48 pathology centers participated in the EQA. Of these, 47 (97.9%) centers submitted their analyses within the pre-defined time frame and 44 (tissue), respectively, 40 (plasma) successfully passed the test. The overall success rates in the RRT phase II were 91.7% (tissue) and 83.3% (blood), respectively. Thirty-eight out of 48 participants (79.2%) successfully passed both parts of the RRT. The RRT for blood-based EGFR testing initiated in Germany is, to the best of our knowledge, the first of his kind in Europe. In summary, our results demonstrate that blood-based genotyping for EGFR resistance mutations can be successfully integrated in routine molecular diagnostics complementing the array of molecular methods already available at pathology centers in Germany.

Electrodiagnostic applications of somatosensory evoked high-frequency EEG oscillations: Technical considerations.

PubMed

Simpson, A J; Cunningham, M O; Baker, M R

2018-03-01

High frequency oscillations (HFOs) embedded within the somatosensory evoked potential (SEP) are not routinely recorded/measured as part of standard clinical SEPs. However, HFOs could provide important additional diagnostic/prognostic information in various patient groups in whom SEPs are tested routinely. One area is the management of patients with hypoxic ischaemic encephalopathy (HIE) in the intensive care unit (ICU). However, the sensitivity of standard clinical SEP recording techniques for detecting HFOs is unknown. SEPs were recorded using routine clinical methods in 17 healthy subjects (median nerve stimulation; 0.5 ms pulse width; 5 Hz; maximum 4000 stimuli) in an unshielded laboratory. Bipolar EEG recordings were acquired (gain 50 k; bandpass 3Hz-2 kHz; sampling rate 5 kHz; non-inverting electrode 2 cm anterior to C3/C4; inverting electrode 2 cm posterior to C3/C4). Data analysis was performed in MATLAB. SEP-HFOs were detected in 65% of controls using standard clinical recording techniques. In 3 controls without significant HFOs, experiments were repeated using a linear electrode array with higher spatial sampling frequency. SEP-HFOs were observed in all 3 subjects. Currently standard clinical methods of recording SEPs are not sufficiently sensitive to permit the inclusion of SEP-HFOs in routine clinical diagnostic/prognostic assessments. Whilst an increase in the number/density of EEG electrodes should improve the sensitivity for detecting SEP-HFOs, this requires confirmation. By improving and standardising clinical SEP recording protocols to permit the acquisition/analysis of SEP-HFOs, it should be possible to gain important insights into the pathophysiology of neurological disorders and refine the management of conditions such as HIE. Copyright © 2018. Published by Elsevier Inc.

Clinical interpretation of antinuclear antibody tests in systemic rheumatic diseases

PubMed Central

Mercado, Monica Vázquez-Del; Chan, Edward K. L.

2010-01-01

Autoantibody tests have been used extensively in diagnosis and follow-up of patients in rheumatology clinics. Immunofluorescent antinuclear antibody test using HEp-2 cells is still considered the gold standard for screening of autoantibodies, and most of specific autoantibodies are currently tested by ELISA as a next step. Among the many autoantibody specificities described, some have been established as clinically useful diagnostic markers and are included in the classification criteria of diseases. Despite a long history of routine tests and attempts to standardize such assays, there are still limitations and problems that clinicians need to be aware of. Clinicians should be able to use autoantibody tests more efficiently and effectively with a basic knowledge on the significance of and potential problems in autoantibody tests. PMID:19277826

A review of ultrasonographic methods for the assessment of the anterior cruciate ligament in patients with knee instability – diagnostics using a posterior approach

PubMed Central

Kielar, Maciej

2016-01-01

Aim The purpose of the study was to improve the ultrasonographic assessment of the anterior cruciate ligament by an inclusion of a dynamic element. The proposed functional modification aims to restore normal posterior cruciate ligament tension, which is associated with a visible change in the ligament shape. This method reduces the risk of an error resulting from subjectively assessing the shape of the posterior cruciate ligament. It should be also emphasized that the method combined with other ultrasound anterior cruciate ligament assessment techniques helps increase diagnostic accuracy. Methods Ultrasonography is used as an adjunctive technique in the diagnosis of anterior cruciate ligament injury. The paper presents a sonographic technique for the assessment of suspected anterior cruciate ligament insufficiency supplemented by the use of a dynamic examination. This technique can be recommended as an additional procedure in routine ultrasound diagnostics of anterior cruciate ligament injuries. Results Supplementing routine ultrasonography with the dynamic assessment of posterior cruciate ligament shape changes in patients with suspected anterior cruciate ligament injury reduces the risk of subjective errors and increases diagnostic accuracy. This is important especially in cases of minor anterior knee instability and bilateral anterior knee instability. Conclusions An assessment of changes in posterior cruciate ligament using a dynamic ultrasound examination effectively complements routine sonographic diagnostic techniques for anterior cruciate ligament insufficiency. PMID:27679732

A diagnostic algorithm for atypical spitzoid tumors: guidelines for immunohistochemical and molecular assessment.

PubMed

Cho-Vega, Jeong Hee

2016-07-01

Atypical spitzoid tumors are a morphologically diverse group of rare melanocytic lesions most frequently seen in children and young adults. As atypical spitzoid tumors bear striking resemblance to Spitz nevus and spitzoid melanomas clinically and histopathologically, it is crucial to determine its malignant potential and predict its clinical behavior. To date, many researchers have attempted to differentiate atypical spitzoid tumors from unequivocal melanomas based on morphological, immonohistochemical, and molecular diagnostic differences. A diagnostic algorithm is proposed here to assess the malignant potential of atypical spitzoid tumors by using a combination of immunohistochemical and cytogenetic/molecular tests. Together with classical morphological evaluation, this algorithm includes a set of immunohistochemistry assays (p16(Ink4a), a dual-color Ki67/MART-1, and HMB45), fluorescence in situ hybridization (FISH) with five probes (6p25, 8q24, 11q13, CEN9, and 9p21), and an array-based comparative genomic hybridization. This review discusses details of the algorithm, the rationale of each test used in the algorithm, and utility of this algorithm in routine dermatopathology practice. This algorithmic approach will provide a comprehensive diagnostic tool that complements conventional histological criteria and will significantly contribute to improve the diagnosis and prediction of the clinical behavior of atypical spitzoid tumors.

Advances in malaria elimination in Botswana: a dramatic shift to parasitological diagnosis, 2008–2014

PubMed Central

Edwards, J. K.; Motlaleng, M.; Namboze, J.; Butt, W.; Obopile, M.; Mosweunyane, T.; Manzi, M.; Takarinda, K. C.; Owiti, P.

2018-01-01

Background: Malaria elimination requires infection detection using quality assured diagnostics and appropriate treatment regimens. Although Botswana is moving towards malaria elimination, reports of unconfirmed cases may jeopardise this effort. This study aimed to determine the proportion of cases treated for malaria that were confirmed by rapid diagnostic testing (RDT) and/or microscopy. Methods: This was a retrospective descriptive study using routine national data from the integrated disease surveillance and case-based surveillance systems from 2008 to 2014. The data were categorised into clinical and confirmed cases each year. An analysis of the data on cases registered in three districts that reported approximately 70% of all malaria cases was performed, stratified by year, type of reporting health facilities and diagnostic method. Results: During 2008–2014, 50 487 cases of malaria were reported in Botswana, and the proportion of RDT and/or blood microscopy confirmed cases improved from 6% in 2008 to 89% in 2013. The total number of malaria cases decreased by 97% in the same period, then increased by 41% in 2013. Conclusion: This study shows that malaria diagnostic tests dramatically improved malaria diagnosis and consequently reduced the malaria burden in Botswana. The study identified a need to build capacity on microscopy for species identification, parasite quantification and guiding treatment choices. PMID:29713592

[Microbiological point of care tests].

PubMed

Book, Malte; Lehmann, Lutz Eric; Zhang, Xianghong; Stüber, Frank

2010-11-01

It is well known that the early initiation of a specific antiinfective therapy is crucial to reduce the mortality in severe infection. Procedures culturing pathogens are the diagnostic gold standard in such diseases. However, these methods yield results earliest between 24 to 48 hours. Therefore, severe infections such as sepsis need to be treated with an empirical antimicrobial therapy, which is ineffective in an unknown fraction of these patients. Today's microbiological point of care tests are pathogen specific and therefore not appropriate for an infection with a variety of possible pathogens. Molecular nucleic acid diagnostics such as polymerase chain reaction (PCR) allow the identification of pathogens and resistances. These methods are used routinely to speed up the analysis of positive blood cultures. The newest PCR based system allows the identification of the 25 most frequent sepsis pathogens by PCR in parallel without previous culture in less than 6 hours. Thereby, these systems might shorten the time of possibly insufficient antiinfective therapy. However, these extensive tools are not suitable as point of care diagnostics. Miniaturization and automating of the nucleic acid based method is pending, as well as an increase of detectable pathogens and resistance genes by these methods. It is assumed that molecular PCR techniques will have an increasing impact on microbiological diagnostics in the future. © Georg Thieme Verlag Stuttgart · New York.

Advances in malaria elimination in Botswana: a dramatic shift to parasitological diagnosis, 2008-2014.

PubMed

Moakofhi, K; Edwards, J K; Motlaleng, M; Namboze, J; Butt, W; Obopile, M; Mosweunyane, T; Manzi, M; Takarinda, K C; Owiti, P

2018-04-25

Background: Malaria elimination requires infection detection using quality assured diagnostics and appropriate treatment regimens. Although Botswana is moving towards malaria elimination, reports of unconfirmed cases may jeopardise this effort. This study aimed to determine the proportion of cases treated for malaria that were confirmed by rapid diagnostic testing (RDT) and/or microscopy. Methods: This was a retrospective descriptive study using routine national data from the integrated disease surveillance and case-based surveillance systems from 2008 to 2014. The data were categorised into clinical and confirmed cases each year. An analysis of the data on cases registered in three districts that reported approximately 70% of all malaria cases was performed, stratified by year, type of reporting health facilities and diagnostic method. Results: During 2008-2014, 50 487 cases of malaria were reported in Botswana, and the proportion of RDT and/or blood microscopy confirmed cases improved from 6% in 2008 to 89% in 2013. The total number of malaria cases decreased by 97% in the same period, then increased by 41% in 2013. Conclusion: This study shows that malaria diagnostic tests dramatically improved malaria diagnosis and consequently reduced the malaria burden in Botswana. The study identified a need to build capacity on microscopy for species identification, parasite quantification and guiding treatment choices.

Evaluation of a New Immunochromatography Technology Test (LDBio Diagnostics) To Detect Toxoplasma IgG and IgM: Comparison with the Routine Architect Technique

PubMed Central

Flori, Pierre; Delaunay, Edouard; Guillerme, Cécile; Charaoui, Sana; Raberin, Hélène; Hafid, Jamal; L'Ollivier, Coralie

2017-01-01

ABSTRACT A study comparing the ICT (immunochromatography technology) Toxoplasma IgG and IgM rapid diagnostic test (LDBio Diagnostics, France) with a fully automated system, Architect, was performed on samples from university hospitals of Marseille and Saint-Etienne. A total of 767 prospective sera and 235 selected sera were collected. The panels were selected to test various IgG and IgM parameters. The reference technique, Toxoplasma IgGII Western blot analysis (LDBio Diagnostics), was used to confirm the IgG results, and commercial kits Platelia Toxo IgM (Bio-Rad) and Toxo-ISAgA (bioMérieux) were used in Saint-Etienne and Marseille, respectively, as the IgM reference techniques. Sensitivity and specificity of the ICT and the Architect IgG assays were compared using a prospective panel. Sensitivity was 100% for the ICT test and 92.1% for Architect (cutoff at 1.6 IU/ml). The low-IgG-titer serum results confirmed that ICT sensitivity was superior to that of Architect. Specificity was 98.7% (ICT) and 99.8% (Architect IgG). The ICT test is also useful for detecting IgM without IgG and is both sensitive (100%) and specific (100%), as it can distinguish nonspecific IgM from specific Toxoplasma IgM. In comparison, IgM sensitivity and specificity on Architect are 96.1% and 99.6%, respectively (cutoff at 0.5 arbitrary units [AU]/ml). To conclude, this new test overcomes the limitations of automated screening techniques, which are not sensitive enough for IgG and lack specificity for IgM (rare IgM false-positive cases). PMID:28954897

Diagnostic efficiency of abattoir meat inspection service in Ethiopia to detect carcasses infected with Mycobacterium bovis: implications for public health.

PubMed

Biffa, Demelash; Bogale, Asseged; Skjerve, Eystein

2010-08-06

Bovine Tuberculosis (BTB) is a widespread and endemic disease of cattle in Ethiopia posing a significant threat to public health. Regular surveillance by skin test, bacteriology and molecular methods is not feasible due to lack of resource. Thus, routine abattoir (RA) inspection will continue to play a key role for national surveillance. We evaluated efficiency of RA inspection for diagnosis of Mycobacterium bovis infection and discussed its public health implications in light of a high risk of human exposure. The study was conducted in five abattoirs: Addis Ababa, Adama, Hawassa, Yabello and Melge-Wondo abattoirs. The efficiency of routine abattoir (RA) inspection was validated in comparison to detailed abattoir (DA) inspection, followed by culture and microscopy (CM) and region of difference (RD) deletion analysis. Diagnostic accuracies (with corresponding measures of statistical uncertainty) were determined by computing test property statistics (sensitivity and specificity) and likelihood estimations using web-based SISA diagnostic statistics software. Post-test probability of detecting TB infected carcasses was estimated using nomograms. Agreement between RA and DA inspections was measured using kappa statistics. The study was conducted and reported in accordance with standards for reporting of diagnostic accuracy (STARD) requirements. Both routine and detailed meat inspection protocols were performed on a subpopulation of 3322 cattle selected randomly from among 78,269 cattle slaughtered during the study period. Three hundred thirty seven carcasses identified through detailed meat inspection protocols were subjected to culture and microscopy; of the 337, a subset of 105 specimens for culture and microscopy were subjected to further molecular testing. There was a substantial agreement between RA and DA inspections in Addis Ababa (Kappa = 0.7) and Melge-Wondo abattoirs (Kappa = 0.67). In Adama, Hawassa and Yabello abattoirs, the agreement was however poor (Kappa

Diagnostic efficiency of abattoir meat inspection service in Ethiopia to detect carcasses infected with Mycobacterium bovis: Implications for public health

PubMed Central

2010-01-01

Background Bovine Tuberculosis (BTB) is a widespread and endemic disease of cattle in Ethiopia posing a significant threat to public health. Regular surveillance by skin test, bacteriology and molecular methods is not feasible due to lack of resource. Thus, routine abattoir (RA) inspection will continue to play a key role for national surveillance. We evaluated efficiency of RA inspection for diagnosis of Mycobacterium bovis infection and discussed its public health implications in light of a high risk of human exposure. Methods The study was conducted in five abattoirs: Addis Ababa, Adama, Hawassa, Yabello and Melge-Wondo abattoirs. The efficiency of routine abattoir (RA) inspection was validated in comparison to detailed abattoir (DA) inspection, followed by culture and microscopy (CM) and region of difference (RD) deletion analysis. Diagnostic accuracies (with corresponding measures of statistical uncertainty) were determined by computing test property statistics (sensitivity and specificity) and likelihood estimations using web-based SISA diagnostic statistics software. Post-test probability of detecting TB infected carcasses was estimated using nomograms. Agreement between RA and DA inspections was measured using kappa statistics. The study was conducted and reported in accordance with standards for reporting of diagnostic accuracy (STARD) requirements. Both routine and detailed meat inspection protocols were performed on a subpopulation of 3322 cattle selected randomly from among 78,269 cattle slaughtered during the study period. Three hundred thirty seven carcasses identified through detailed meat inspection protocols were subjected to culture and microscopy; of the 337, a subset of 105 specimens for culture and microscopy were subjected to further molecular testing. Results There was a substantial agreement between RA and DA inspections in Addis Ababa (Kappa = 0.7) and Melge-Wondo abattoirs (Kappa = 0.67). In Adama, Hawassa and Yabello abattoirs, the agreement was however poor (Kappa ≤ 0.2). RA inspection was able to detect only 117 of the total 3322 carcasses inspected (3.5%). The sensitivity (Sn) and specificity (Sp) of RA inspection were 28.2% (95/337) [95%CI: 23.4-33.0] and 99.3% (2963/2985) [95%CI: 99.0-99.6], respectively, when DA inspection was considered as reference test. When culture and microscopy (CM) was considered as reference test, the Sn and Sp of RA were 55.2% (58/105) [95%CI: 45.7-64.7] and 84.1% (195/232) [95%CI: 79.3-88.8]. RA inspection failed to detect 71.8% (242/337) and 44.8% (47/105) of TB infected carcasses as judged by DA inspection and CM, respectively. On the other hand, a much higher sensitivity of DA was obtained when CM and RD deletion analysis were considered as reference tests (96.3% (105/109) and 100.0% (24/24), respectively). Conclusions The study results indicate that meat inspection protocols currently utilized in abattoirs are insufficient to detect the majority of TB lesions at the gross level. DA inspection protocols were demonstrated to improve the detection level by approximately 3-fold. The failure of current inspection techniques to detect approximately 70% of carcasses presented with grossly-visible lesions of TB at the slaughter-plants indicates the magnitude of meat-borne zoonotic TB as an on-going risk to public health. Standardization of abattoir inspection protocols (in line with international sanitary requirements), enhanced training and proficiency testing of meat inspections, and raising public awareness are recommended as essential and cost-effective interventions to improve meat inspection service in Ethiopia, with subsequent protection of consumers' health. PMID:20691081

Autovalidation and automation of the postanalytical phase of routine hematology and coagulation analyses in a university hospital laboratory.

PubMed

Mlinaric, Ana; Milos, Marija; Coen Herak, Désirée; Fucek, Mirjana; Rimac, Vladimira; Zadro, Renata; Rogic, Dunja

2018-02-23

The need to satisfy high-throughput demands for laboratory tests continues to be a challenge. Therefore, we aimed to automate postanalytical phase in hematology and coagulation laboratory by autovalidation of complete blood count (CBC) and routine coagulation test results (prothrombin time [PT], international normalized ratio [PT-INR], activated partial thromboplastin time [APTT], fibrinogen, antithrombin activity [AT] and thrombin time [TT]). Work efficacy and turnaround time (TAT) before and after implementation of automated solutions will be compared. Ordering panels tailored to specific patient populations were implemented. Rerun and reflex testing rules were set in the respective analyzers' software (Coulter DxH Connectivity 1601, Beckman Coulter, FL, USA; AutoAssistant, Siemens Healthcare Diagnostics, Germany), and sample status information was transferred into the laboratory information system. To evaluate if the automation improved TAT and efficacy, data from manually verified results in September and October of 2015 were compared with the corresponding period in 2016 when autovalidation was implemented. Autovalidation rates of 63% for CBC and 65% for routine coagulation test results were achieved. At the TAT of 120 min, the percentage of reported results increased substantially for all analyzed tests, being above 90% for CBC, PT, PT-INR and fibrinogen and 89% for APTT. This output was achieved with three laboratory technicians less compared with the period when the postanalytical phase was not automated. Automation allowed optimized laboratory workflow for specific patient populations, thereby ensuring standardized results reporting. Autovalidation of test results proved to be an efficient tool for improvement of laboratory work efficacy and TAT.

Imaging markers for Alzheimer disease

PubMed Central

Bocchetta, Martina; Chételat, Gael; Rabinovici, Gil D.; de Leon, Mony J.; Kaye, Jeffrey; Reiman, Eric M.; Scheltens, Philip; Barkhof, Frederik; Black, Sandra E.; Brooks, David J.; Carrillo, Maria C.; Fox, Nick C.; Herholz, Karl; Nordberg, Agneta; Jack, Clifford R.; Jagust, William J.; Johnson, Keith A.; Rowe, Christopher C.; Sperling, Reisa A.; Thies, William; Wahlund, Lars-Olof; Weiner, Michael W.; Pasqualetti, Patrizio; DeCarli, Charles

2013-01-01

Revised diagnostic criteria for Alzheimer disease (AD) acknowledge a key role of imaging biomarkers for early diagnosis. Diagnostic accuracy depends on which marker (i.e., amyloid imaging, 18F-fluorodeoxyglucose [FDG]-PET, SPECT, MRI) as well as how it is measured (“metric”: visual, manual, semiautomated, or automated segmentation/computation). We evaluated diagnostic accuracy of marker vs metric in separating AD from healthy and prognostic accuracy to predict progression in mild cognitive impairment. The outcome measure was positive (negative) likelihood ratio, LR+ (LR−), defined as the ratio between the probability of positive (negative) test outcome in patients and the probability of positive (negative) test outcome in healthy controls. Diagnostic LR+ of markers was between 4.4 and 9.4 and LR− between 0.25 and 0.08, whereas prognostic LR+ and LR− were between 1.7 and 7.5, and 0.50 and 0.11, respectively. Within metrics, LRs varied up to 100-fold: LR+ from approximately 1 to 100; LR− from approximately 1.00 to 0.01. Markers accounted for 11% and 18% of diagnostic and prognostic variance of LR+ and 16% and 24% of LR−. Across all markers, metrics accounted for an equal or larger amount of variance than markers: 13% and 62% of diagnostic and prognostic variance of LR+, and 29% and 18% of LR−. Within markers, the largest proportion of diagnostic LR+ and LR− variability was within 18F-FDG-PET and MRI metrics, respectively. Diagnostic and prognostic accuracy of imaging AD biomarkers is at least as dependent on how the biomarker is measured as on the biomarker itself. Standard operating procedures are key to biomarker use in the clinical routine and drug trials. PMID:23897875

Feasibility of using microbiology diagnostic tests of moderate or high complexity at the point - of - care in a delivery suite.

PubMed

Gray, J W; Milner, P J; Edwards, E H; Daniels, J P; Khan, K S

2012-07-01

Point-of-care testing (POCT) is one of the fastest growing sectors of laboratory diagnostics. Most tests in routine use are haematology or biochemistry tests that are of low complexity. Microbiology POCT has been constrained by a lack of tests that are both accurate and of low complexity. We describe our experience of the practical issues around using more complex POCT for detection of Group B streptococci (GBS) in swabs from labouring women. We evaluated two tests for their feasibility in POCT: an optical immune assay (Biostar OIA Strep B, Inverness Medical, Princetown, NJ) and a PCR (IDI-Strep B, Cepheid, Sunnyvale, CA), which have been categorised as being of moderate and high complexity, respectively. A total of 12 unqualified midwifery assistants (MA) were trained to undertake testing on the delivery suite. A systematic approach to the introduction and management of POC testing was used. Modelling showed that the probability of test results being available within a clinically useful timescale was high. However, in the clinical setting, we found it impossible to maintain reliable availability of trained testers. Implementation of more complex POC testing is technically feasible, but it is expensive, and may be difficult to achieve in a busy delivery suite.

Betrixaban: Impact on Routine and Specific Coagulation Assays-A Practical Laboratory Guide.

PubMed

Siriez, Romain; Evrard, Jonathan; Dogné, Jean-Michel; Pochet, Lionel; Gheldof, Damien; Chatelain, Bernard; Mullier, François; Douxfils, Jonathan

2018-06-11

 Betrixaban is a novel direct oral factor Xa inhibitor approved by the Food and Drug Administration for prophylaxis of venous thromboembolism in adult patients hospitalized for an acute illness at risk for thromboembolic complications. Assessment of the anti-coagulant effect of betrixaban may be useful in some situations. Also, clinicians need to know how routine coagulation assays are influenced.  The aim of this study is to determine which coagulation assay(s) should be used to assess the impact of betrixaban on haemostasis and provide laboratory guidance for their interpretation.  Betrixaban was spiked at final concentrations ranging from 0 to 250 ng/mL in platelet-poor plasma. Different reagents from several manufacturers were tested and the impact of betrixaban on pro-thrombin time (PT), activated partial thromboplastin time (aPTT), dilute Russel viper venom time (dRVV-T), chromogenic anti-Xa assays, thrombin generation assay (TGA), and a large panel of haemostasis diagnostic tests has been assessed.  A concentration-dependent prolongation of aPTT, PT and dRVV-T is observed. The sensitivity mainly depends on the reagent. Chromogenic anti-Xa assays show high sensitivity depending on the reagent and/or the methodology. These assays applicable for other direct factor Xa inhibitors have to be adapted to obtain a relevant range of measurement. TGA may also be attractive to assess the anti-coagulant activity of betrixaban.  Adapted chromogenic anti-Xa assays are the most appropriate assays to estimate the concentration of betrixaban. Betrixaban significantly affects several haemostasis diagnostic tests and this needs to be taken into consideration when requesting and interpreting such tests. Schattauer GmbH Stuttgart.

Evaluation of the indirect fluorescent antibody test as a diagnostic tool for East Coast fever in eastern Zambia.

PubMed

Billiouw, M; Brandt, J; Vercruysse, J; Speybroeck, N; Marcotty, T; Mulumba, M; Berkvens, D

2005-02-28

Serological surveys using the schizont indirect fluorescence antibody test (IFAt) are routinely carried out to monitor the Theileria parva infection prevalence. The present study evaluates the diagnostic accuracy of the IFAt in eastern Zambia, where the transmission of T. parva is highly seasonal. The data set resulted from a sentinel herd (n = 105 animals) study carried out between 1995 and 2000 and was split into an epidemic period, during which the majority of the cattle became infected, and an endemic period with seasonal disease incidence in calves. In the epidemic period the T. parva seroprevalence followed closely the build up of the herd immunity. In the endemic period the seroprevalence fluctuates considerably although most of the animals had been infected. Overall, the diagnostic sensitivity of the IFA test was 55% at cut-off titre 1:40 and 28% at cut-off 1:160. The specificity of the test was 86 and 95%, respectively. A logistic regression model demonstrates that the sensitivity is significantly lower when the T. parva transmission is low (p < 0.01). The analysis of receiver operator characteristic curves classifies the test as moderately accurate (area under the curve, AUC = 0.79) during the epidemic period and less accurate in the endemic period (AUC = 0.63). Neonatal serology surveys yield a better estimate of the infection prevalence. The sensitivity of the neonatal test was 73% at cut-off titre 1:40 and 24% at cut-off 1:160.

Diagnostic value of the near-nerve needle sensory nerve conduction in sensory inflammatory demyelinating polyneuropathy.

PubMed

Odabasi, Zeki; Oh, Shin J

2018-03-01

In this study we report the diagnostic value of the near-nerve needle sensory nerve conduction study (NNN-SNCS) in sensory inflammatory demyelinating polyneuropathy (IDP) in which the routine nerve conduction study was normal or non-diagnostic. The NNN-SNCS was performed to identify demyelination in the plantar nerves in 14 patients and in the median or ulnar nerve in 2 patients with sensory IDP. In 16 patients with sensory IDP, routine NCSs were either normal or non-diagnostic for demyelination. Demyelination was identified by NNN-SNCS by dispersion and/or slow nerve conduction velocity (NCV) below the demyelination marker. Immunotherapy was initiated in 11 patients, 10 of whom improved or remained stable. NNN-SNCS played an essential role in identifying demyelinaton in 16 patients with sensory IDP, leading to proper treatment. Muscle Nerve 57: 414-418, 2018. © 2017 Wiley Periodicals, Inc.

Effect of routine diagnostic imaging for patients with musculoskeletal disorders: A meta-analysis.

PubMed

Karel, Yasmaine H J M; Verkerk, Karin; Endenburg, Silvio; Metselaar, Sven; Verhagen, Arianne P

2015-10-01

The increasing use of diagnostic imaging has led to high expenditures, unnecessary invasive procedures and/or false-positive diagnoses, without certainty that the patients actually benefit from these imaging procedures. This review explores whether diagnostic imaging leads to better patient-reported outcomes in individuals with musculoskeletal disorders. Databases were searched from inception to September 2013, together with scrutiny of selected bibliographies. Trials were eligible when: 1) a diagnostic imaging procedure was compared with any control group not getting or not receiving the results of imaging; 2) the population included individuals suffering from musculoskeletal disorders, and 3) if patient-reported outcomes were available. Primary outcome measures were pain and function. Secondary outcome measures were satisfaction and quality of life. Subgroup analysis was done for different musculoskeletal complaints and high technological medical imaging (MRI/CT). Eleven trials were eligible. The effects of diagnostic imaging were only evaluated in patients with low back pain (n=7) and knee complaints (n=4). Overall, there was a moderate level of evidence for no benefit of diagnostic imaging on all outcomes compared with controls. A significant but clinically irrelevant effect was found in favor of no (routine) imaging in low back pain patients in terms of pain severity at short [SMD 0.17 (0.04-0.31)] and long-term follow-up [SMD 0.13 (0.02-0.24)], and for overall improvement [RR 1.15 (1.03-1.28)]. Subgroup analysis did not significantly change these results. These results strengthen the available evidence that routine referral to diagnostic imaging by general practitioners for patients with knee and low back pain yields little to no benefit. Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Review of the current state of whole slide imaging in pathology

PubMed Central

Pantanowitz, Liron; Valenstein, Paul N.; Evans, Andrew J.; Kaplan, Keith J.; Pfeifer, John D.; Wilbur, David C.; Collins, Laura C.; Colgan, Terence J.

2011-01-01

Whole slide imaging (WSI), or “virtual” microscopy, involves the scanning (digitization) of glass slides to produce “digital slides”. WSI has been advocated for diagnostic, educational and research purposes. When used for remote frozen section diagnosis, WSI requires a thorough implementation period coupled with trained support personnel. Adoption of WSI for rendering pathologic diagnoses on a routine basis has been shown to be successful in only a few “niche” applications. Wider adoption will most likely require full integration with the laboratory information system, continuous automated scanning, high-bandwidth connectivity, massive storage capacity, and more intuitive user interfaces. Nevertheless, WSI has been reported to enhance specific pathology practices, such as scanning slides received in consultation or of legal cases, of slides to be used for patient care conferences, for quality assurance purposes, to retain records of slides to be sent out or destroyed by ancillary testing, and for performing digital image analysis. In addition to technical issues, regulatory and validation requirements related to WSI have yet to be adequately addressed. Although limited validation studies have been published using WSI there are currently no standard guidelines for validating WSI for diagnostic use in the clinical laboratory. This review addresses the current status of WSI in pathology related to regulation and validation, the provision of remote and routine pathologic diagnoses, educational uses, implementation issues, and the cost-benefit analysis of adopting WSI in routine clinical practice. PMID:21886892

Metagenomic Analysis of Viruses in Feces from Unsolved Outbreaks of Gastroenteritis in Humans

PubMed Central

Moore, Nicole E.; Wang, Jing; Hewitt, Joanne; Croucher, Dawn; Williamson, Deborah A.; Paine, Shevaun; Yen, Seiha; Greening, Gail E.

2014-01-01

The etiology of an outbreak of gastroenteritis in humans cannot always be determined, and ∼25% of outbreaks remain unsolved in New Zealand. It is hypothesized that novel viruses may account for a proportion of unsolved cases, and new unbiased high-throughput sequencing methods hold promise for their detection. Analysis of the fecal metagenome can reveal the presence of viruses, bacteria, and parasites which may have evaded routine diagnostic testing. Thirty-one fecal samples from 26 gastroenteritis outbreaks of unknown etiology occurring in New Zealand between 2011 and 2012 were selected for de novo metagenomic analysis. A total data set of 193 million sequence reads of 150 bp in length was produced on an Illumina MiSeq. The metagenomic data set was searched for virus and parasite sequences, with no evidence of novel pathogens found. Eight viruses and one parasite were detected, each already known to be associated with gastroenteritis, including adenovirus, rotavirus, sapovirus, and Dientamoeba fragilis. In addition, we also describe the first detection of human parechovirus 3 (HPeV3) in Australasia. Metagenomics may thus provide a useful audit tool when applied retrospectively to determine where routine diagnostic processes may have failed to detect a pathogen. PMID:25339401

Evidence of dose saving in routine CT practice using iterative reconstruction derived from a national diagnostic reference level survey.

PubMed

Thomas, P; Hayton, A; Beveridge, T; Marks, P; Wallace, A

2015-09-01

To assess the influence and significance of the use of iterative reconstruction (IR) algorithms on patient dose in CT in Australia. We examined survey data submitted to the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) National Diagnostic Reference Level Service (NDRLS) during 2013 and 2014. We compared median survey dose metrics with categorization by scan region and use of IR. The use of IR results in a reduction in volume CT dose index of between 17% and 44% and a reduction in dose-length product of between 14% and 34% depending on the specific scan region. The reduction was highly significant (p < 0.001, Wilcoxon rank-sum test) for all six scan regions included in the NDRLS. Overall, 69% (806/1167) of surveys included in the analysis used IR. The use of IR in CT is achieving dose savings of 20-30% in routine practice in Australia. IR appears to be widely used by participants in the ARPANSA NDRLS with approximately 70% of surveys submitted employing this technique. This study examines the impact of the use of IR on patient dose in CT on a national scale.

Guide for diagnosis and treatment of hepatocellular carcinoma

PubMed Central

Attwa, Magdy Hamed; El-Etreby, Shahira Aly

2015-01-01

Hepatocellular carcinoma (HCC) is ranked as the 5th common type of cancer worldwide and is considered as the 3rd common reason for cancer-related deaths. HCC often occurs on top of a cirrhotic liver. The prognosis is determined by several factors; tumour extension, alpha-fetoprotein (AFP) concentration, histologic subtype of the tumour, degree of liver dysfunction, and the patient’s performance status. HCC prognosis is strongly correlated with diagnostic delay. To date, no ideal screening modality has been developed. Analysis of recent studies showed that AFP assessment lacks adequate sensitivity and specificity for effective surveillance and diagnosis. Many tumour markers have been tested in clinical trials without progressing to routine use in clinical practice. Thus, surveillance is still based on ultrasound (US) examination every 6 mo. Imaging studies for diagnosis of HCC can fall into one of two main categories: routine non-invasive studies such as US, computed tomography (CT), and magnetic resonance imaging, and more specialized invasive techniques including CT during hepatic arteriography and CT arterial portography in addition to the conventional hepatic angiography. This article provides an overview and spotlight on the different diagnostic modalities and treatment options of HCC. PMID:26140083

Overcoming the errors of in-house PCR used in the clinical laboratory for the diagnosis of extrapulmonary tuberculosis.

PubMed

Kunakorn, M; Raksakai, K; Pracharktam, R; Sattaudom, C

1999-03-01

Our experiences from 1993 to 1997 in the development and use of IS6110 base PCR for the diagnosis of extrapulmonary tuberculosis in a routine clinical setting revealed that error-correcting processes can improve existing diagnostic methodology. The reamplification method initially used had a sensitivity of 90.91% and a specificity of 93.75%. The concern was focused on the false positive results of this method caused by product-carryover contamination. This method was changed to single round PCR with carryover prevention by uracil DNA glycosylase (UDG), resulting in a 100% specificity but only 63% sensitivity. Dot blot hybridization was added after the single round PCR, increasing the sensitivity to 87.50%. However, false positivity resulted from the nonspecific dot blot hybridization signal, reducing the specificity to 89.47%. The hybridization of PCR was changed to a Southern blot with a new oligonucleotide probe giving the sensitivity of 85.71% and raising the specificity to 99.52%. We conclude that the PCR protocol for routine clinical use should include UDG for carryover prevention and hybridization with specific probes to optimize diagnostic sensitivity and specificity in extrapulmonary tuberculosis testing.

Aortic stiffness improves the prediction of both diagnosis and severity of coronary artery disease.

PubMed

Yannoutsos, Alexandra; Ahouah, Mathieu; Dreyfuss Tubiana, Céline; Topouchian, Jirar; Safar, Michel E; Blacher, Jacques

2018-02-01

Elective coronography has low diagnostic yield for obstructive coronary artery disease (CAD). We aim to determine whether non-invasive aortic stiffness assessment improves diagnostic accuracy of CAD screening by reducing the number of false-positive results from the cardiac stress test. A cross-sectional study was conducted from January 2013 to September 2014 in our medical center. Electrocardiogram (ECG) stress test coupled with nuclear imaging was performed in 367 consecutive patients routinely followed for myocardial ischemia screening. Aortic pulse wave velocity (PWV) was assessed by applanation tonometry in the overall population. Forty-two patients underwent elective coronography because of ischemia. Theoretical PWV was calculated according to age, blood pressure and gender. The results were expressed as an index ((measured PWV-theoretical PWV)/theoretical PWV) for each patient. Ten patients presented with obstructive CAD, 16 patients had non-obstructive CAD and 16 patients had normal coronary angiography. PWV index and severity of CAD were positively correlated (P=0.001). All patients with obstructive CAD had a positive PWV index. When considering the PWV index retrospectively, the false positive results of cardiac stress test were significantly reduced (P<0.001). Twenty-three procedures may have been avoided in the present study cohort. The salient finding of this study was that in patients with known or suspected CAD, routinely followed aortic PWV index may be considered clinically useful for reducing the rate of unnecessary invasive angiographies. The clinical relevance of this individualized decision approach should be confirmed in a large-scale study. Prospective studies have the potential to evaluate the PWV index as a marker of CAD.

Hematology of the domestic ferret (Mustela putorius furo).

PubMed

Smith, Stephen A; Zimmerman, Kurt; Moore, David M

2015-01-01

Pet ferrets are presented to veterinary clinics for routine care and treatment of clinical diseases and female reproductive problems. In addition to obtaining clinical history, additional diagnostic testing may be required, including hematological assessments. This article describes common blood collection methods, including venipuncture sites, volume of blood that can be safely collected, and handling of the blood. Hematological parameters for normal ferrets are provided along with a description of the morphology of ferret leukocytes to assist in performing a differential count.

Establishing an EGFR mutation screening service for non-small cell lung cancer - sample quality criteria and candidate histological predictors.

PubMed

Leary, Alexandra F; Castro, David Gonzalez de; Nicholson, Andrew G; Ashley, Sue; Wotherspoon, Andrew; O'Brien, Mary E R; Popat, Sanjay

2012-01-01

EGFR screening requires good quality tissue, sensitivity and turn-around time (TAT). We report our experience of routine screening, describing sample type, TAT, specimen quality (cellularity and DNA yield), histopathological description, mutation result and clinical outcome. Non-small cell lung cancer (NSCLC) sections were screened for EGFR mutations (M+) in exons 18-21. Clinical, pathological and screening outcome data were collected for year 1 of testing. Screening outcome alone was collected for year 2. In year 1, 152 samples were tested, most (72%) were diagnostic. TAT was 4.9 days (95%confidence interval (CI)=4.5-5.5). EGFR-M+ prevalence was 11% and higher (20%) among never-smoking women with adenocarcinomas (ADCs), but 30% of mutations occurred in current/ex-smoking men. EGFR-M+ tumours were non-mucinous ADCs and 100% thyroid transcription factor (TTF1+). No mutations were detected in poorly differentiated NSCLC-not otherwise specified (NOS). There was a trend for improved overall survival (OS) among EGFR-M+ versus EGFR-M- patients (median OS=78 versus 17 months). In year 1, test failure rate was 19%, and associated with scant cellularity and low DNA concentrations. However 75% of samples with poor cellularity but representative of tumour were informative and mutation prevalence was 9%. In year 2, 755 samples were tested; mutation prevalence was 13% and test failure only 5.4%. Although samples with low DNA concentration (<2 ng/μL) had more test failures (30% versus 3.9% for [DNA]>2.2 ng/μL), the mutation rate was 9.2%. Routine epidermal growth factor receptor (EGFR) screening using diagnostic samples is fast and feasible even on samples with poor cellularity and DNA content. Mutations tend to occur in better-differentiated non-mucinous TTF1+ ADCs. Whether these histological criteria may be useful to select patients for EGFR testing merits further investigation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Study design requirements for RNA sequencing-based breast cancer diagnostics.

PubMed

Mer, Arvind Singh; Klevebring, Daniel; Grönberg, Henrik; Rantalainen, Mattias

2016-02-01

Sequencing-based molecular characterization of tumors provides information required for individualized cancer treatment. There are well-defined molecular subtypes of breast cancer that provide improved prognostication compared to routine biomarkers. However, molecular subtyping is not yet implemented in routine breast cancer care. Clinical translation is dependent on subtype prediction models providing high sensitivity and specificity. In this study we evaluate sample size and RNA-sequencing read requirements for breast cancer subtyping to facilitate rational design of translational studies. We applied subsampling to ascertain the effect of training sample size and the number of RNA sequencing reads on classification accuracy of molecular subtype and routine biomarker prediction models (unsupervised and supervised). Subtype classification accuracy improved with increasing sample size up to N = 750 (accuracy = 0.93), although with a modest improvement beyond N = 350 (accuracy = 0.92). Prediction of routine biomarkers achieved accuracy of 0.94 (ER) and 0.92 (Her2) at N = 200. Subtype classification improved with RNA-sequencing library size up to 5 million reads. Development of molecular subtyping models for cancer diagnostics requires well-designed studies. Sample size and the number of RNA sequencing reads directly influence accuracy of molecular subtyping. Results in this study provide key information for rational design of translational studies aiming to bring sequencing-based diagnostics to the clinic.

Design and implementation of a controlled clinical trial to evaluate the effectiveness and efficiency of routine opt-out rapid human immunodeficiency virus screening in the emergency department.

PubMed

Haukoos, Jason S; Hopkins, Emily; Byyny, Richard L; Conroy, Amy A; Silverman, Morgan; Eisert, Sheri; Thrun, Mark; Wilson, Michael; Boyett, Brian; Heffelfinger, James D

2009-08-01

In 2006, the Centers for Disease Control and Prevention (CDC) released revised recommendations for performing human immunodeficiency virus (HIV) testing in health care settings, including implementing routine rapid HIV screening, the use of an integrated opt-out consent, and limited prevention counseling. Emergency departments (EDs) have been a primary focus of these efforts. These revised CDC recommendations were primarily based on feasibility studies and have not been evaluated through the application of rigorous research methods. This article describes the design and implementation of a large prospective controlled clinical trial to evaluate the CDC's recommendations in an ED setting. From April 15, 2007, through April 15, 2009, a prospective quasi-experimental equivalent time-samples clinical trial was performed to compare the clinical effectiveness and efficiency of routine (nontargeted) opt-out rapid HIV screening (intervention) to physician-directed diagnostic rapid HIV testing (control) in a high-volume urban ED. In addition, three nested observational studies were performed to evaluate the cost-effectiveness and patient and staff acceptance of the two rapid HIV testing methods. This article describes the rationale, methodologies, and study design features of this program evaluation clinical trial. It also provides details regarding the integration of the principal clinical trial and its nested observational studies. Such ED-based trials are rare, but serve to provide valid comparisons between testing approaches. Investigators should consider similar methodology when performing future ED-based health services research.

Diagnostic accuracy and applicability of a PCR system for the detection of Schistosoma mansoni DNA in human urine samples from an endemic area.

PubMed

Enk, Martin Johannes; Oliveira e Silva, Guilherme; Rodrigues, Nilton Barnabé

2012-01-01

Schistosomiasis caused by Schistosoma mansoni, one of the most neglected human parasitoses in Latin America and Africa, is routinely confirmed by microscopic visualization of eggs in stool. The main limitation of this diagnostic approach is its lack of sensitivity in detecting individual low worm burdens and consequently data on infection rates in low transmission settings are little reliable. According to the scientific literature, PCR assays are characterized by high sensitivity and specificity in detecting parasite DNA in biological samples. A simple and cost effective extraction method for DNA of Schistosoma mansoni from urine samples in combination with a conventional PCR assay was developed and applied in an endemic area. This urine based PCR system was tested for diagnostic accuracy among a population of a small village in an endemic area, comparing it to a reference test composed of three different parasitological techniques. The diagnostic parameters revealed a sensitivity of 100%, a specificity of 91.20%, positive and negative predictive values of 86.25% and 100%, respectively, and a test accuracy of 94.33%. Further statistical analysis showed a k index of 0.8806, indicating an excellent agreement between the reference test and the PCR system. Data obtained from the mouse model indicate the infection can be detected one week after cercariae penetration, opening a new perspective for early detection and patient management during this stage of the disease. The data indicate that this innovative PCR system provides a simple to handle and robust diagnostic tool for the detection of S. mansoni DNA from urine samples and a promising approach to overcome the diagnostic obstacles in low transmission settings. Furthermore the principals of this molecular technique, based on the examination of human urine samples may be useful for the diagnosis of other neglected tropical diseases that can be detected by trans-renal DNA.

State of the art diagnostic of mold diseases: a practical guide for clinicians.

PubMed

Beirão, F; Araujo, R

2013-01-01

The epidemiology of fungal diseases changed, and molds have been increasingly associated with high mortality in severe immunocompromised patients. Invasive mold diseases may originate from the airborne conidia through inhalation or inoculation in skin fissures associated with indwelling catheters, wounds, burns, or onychomycosis. The diagnosis and treatment of fungal diseases is problematic and raises considerable challenges. Diagnosis of invasive mold diseases includes several methodologies, of which the most commonly used are the cultural methods, antigen testing, nucleic acid detection, and radiological imaging. Galactomannan and (1 → 3)-β-D-glucan detection significantly improved mold diagnosis in the last decade. Several molecular strategies have been proposed over the years but no consensus was achieved for standardized protocols or cut-off values. Recently, the first commercially available molecular assay for detection of Aspergillus was tested and the results were highly reproducible. In addition, blood cultures may also be helpful for invasive aspergillosis by following a novel procedure for the recovery of Aspergillus spp. from blood cultures. The association of distinct diagnostic methods, particularly molecular tests, galactomannan, and/or (1 → 3)-β-D-glucan detection, may provide earlier and more sensitive diagnosis of mold diseases and be indicative for early antifungal treatment. Accurate routine use of diagnostic tests can be cost-effective for laboratories and be of great value to patients.

Diagnosing Chronic Pancreatitis.

PubMed

Anaizi, Ahmad; Hart, Phil A; Conwell, Darwin L

2017-07-01

Diagnosing CP can range from routine in those with severe disease and obvious calcifications on CT imaging to elusive in those patients with early changes in CP. The workup of suspected CP should follow a progressively noninvasive to more invasive STEP-wise approach in a patient with a suspicious clinical presentation and risk factors that raise their pretest probability of disease. After a thorough history and physical examination, basic laboratories should be obtained such as lipase, amylase, metabolic panel, and indirect PFTs (fecal elastase-1, serum trypsin). Computed tomography remains the best initial imaging modality to obtain as it has good sensitivity for severe CP and may obviate the need for other diagnostic tests. When equivocal, an MRCP should be obtained for a more detailed evaluation of the both the pancreatic parenchyma and ducts. If the diagnosis remains in doubt, EUS should be performed with or without pancreas function testing. ERCP remains a last-line diagnostic test and seldom should be used outside of therapeutic purposes. Future advances should target optimizing current diagnostic tools to more accurately diagnose early CP, as it is in this population where the benefits of delaying progression of CP may have the most profound effect. Likely the best way at establishing a diagnosis in these patients is via pancreatic function testing in the setting of indeterminate EUS results. Biomarker studies of pancreas fluid may supplement diagnosis.

Diagnostic accuracy of the Thessaly test, standardised clinical history and other clinical examination tests (Apley's, McMurray's and joint line tenderness) for meniscal tears in comparison with magnetic resonance imaging diagnosis.

PubMed

Blyth, Mark; Anthony, Iain; Francq, Bernard; Brooksbank, Katriona; Downie, Paul; Powell, Andrew; Jones, Bryn; MacLean, Angus; McConnachie, Alex; Norrie, John

2015-08-01

Reliable non-invasive diagnosis of meniscal tears is difficult. Magnetic resonance imaging (MRI) is often used but is expensive and incidental findings are problematic. There are a number of physical examination tests for the diagnosis of meniscal tears that are simple, cheap and non-invasive. To determine the diagnostic accuracy of the Thessaly test and to determine if the Thessaly test (alone or in combination with other physical tests) can obviate the need for further investigation by MRI or arthroscopy for patients with a suspected meniscal tear. Single-centre prospective diagnostic accuracy study. Although the study was performed in a secondary care setting, it was designed to replicate the results that would have been achieved in a primary care setting. Two cohorts of patients were recruited: patients with knee pathology (n = 292) and a control cohort with no knee pathology (n = 75). Sensitivity, specificity and diagnostic accuracy of the Thessaly test in determining the presence of meniscal tears. Participants were assessed by both a primary care clinician and a musculoskeletal clinician. Both clinicians performed the Thessaly test, McMurray's test, Apley's test, joint line tenderness test and took a standardised clinical history from the patient. The Thessaly test had a sensitivity of 0.66, a specificity of 0.39 and a diagnostic accuracy of 54% when utilised by primary care clinicians. This compared with a sensitivity of 0.62, a specificity of 0.55 and diagnostic accuracy of 59% when used by musculoskeletal clinicians. The diagnostics accuracy of the other tests when used by primary care clinicians was 54% for McMurray's test, 53% for Apley's test, 54% for the joint line tenderness test and 55% for clinical history. For primary care clinicians, age and past history of osteoarthritis were both significant predictors of MRI diagnosis of meniscal tears. For musculoskeletal clinicians age and a positive diagnosis of meniscal tears on clinical history taking were significant predictors of MRI diagnosis. No physical tests were significant predictors of MRI diagnosis in our multivariate models. The specificity of MRI diagnosis was tested in subgroup of patients who went on to have a knee arthroscopy and was found to be low [0.53 (95% confidence interval 0.28 to 0.77)], although the sensitivity was 1.0. The Thessaly test was no better at diagnosing meniscal tears than other established physical tests. The sensitivity, specificity and diagnostic accuracy of all physical tests was too low to be of routine clinical value as an alternative to MRI. Caution needs to be exercised in the indiscriminate use of MRI scanning in the identification of meniscal tears in the diagnosis of the painful knee, due to the low specificity seen in the presence of concomitant knee pathology. Further research is required to determine the true diagnostic accuracy and cost-effectiveness of MRI for the detection of meniscal tears. Current Controlled Trial ISRCTN43527822. The National Institute for Health Research Health Technology Assessment programme.

Developing a new intelligent system for the diagnosis of tuberculous pleural effusion.

PubMed

Li, Chengye; Hou, Lingxian; Sharma, Bishundat Yanesh; Li, Huaizhong; Chen, ChengShui; Li, Yuping; Zhao, Xuehua; Huang, Hui; Cai, Zhennao; Chen, Huiling

2018-01-01

In countries with high prevalence of tuberculosis (TB), clinicians often diagnose tuberculous pleural effusion (TPE) by using diagnostic tests, which have not only poor sensitivity, but poor availability as well. The aim of our study is to develop a new artificial intelligence based diagnostic model that is accurate, fast, non-invasive and cost effective to diagnose TPE. It is expected that a tool derived based on the model be installed on simple computer devices (such as smart phones and tablets) and be used by clinicians widely. For this study, data of 140 patients whose clinical signs, routine blood test results, blood biochemistry markers, pleural fluid cell type and count, and pleural fluid biochemical tests' results were prospectively collected into a database. An Artificial intelligence based diagnostic model, which employs moth flame optimization based support vector machine with feature selection (FS-MFO-SVM), is constructed to predict the diagnosis of TPE. The optimal model results in an average of 95% accuracy (ACC), 0.9564 the area under the receiver operating characteristic curve (AUC), 93.35% sensitivity, and 97.57% specificity for FS-MFO-SVM. The proposed artificial intelligence based diagnostic model is found to be highly reliable for diagnosing TPE based on simple clinical signs, blood samples and pleural effusion samples. Therefore, the proposed model can be widely used in clinical practice and further evaluated for use as a substitute of invasive pleural biopsies. Copyright © 2017 Elsevier B.V. All rights reserved.

Access to diphtheria antitoxin for therapy and diagnostics.

PubMed

Both, L; White, J; Mandal, S; Efstratiou, A

2014-06-19

The most effective treatment for diphtheria is swift administration of diphtheria antitoxin (DAT) with conjunct antibiotic therapy. DAT is an equine immunoglobulin preparation and listed among the World Health Organization Essential Medicines. Essential Medicines should be available in functioning health systems at all times in adequate amounts, in appropriate dosage forms, with assured quality, and at prices individuals and the community can afford. However, DAT is in scarce supply and frequently unavailable to patients because of discontinued production in several countries, low economic viability, and high regulatory requirements for the safe manufacture of blood-derived products. DAT is also a cornerstone of diphtheria diagnostics but several diagnostic reference laboratories across the European Union (EU) and elsewhere routinely face problems in sourcing DAT for toxigenicity testing. Overall, global access to DAT for both therapeutic and diagnostic applications seems inadequate. Therefore--besides efforts to improve the current supply of DAT--accelerated research and development of alternatives including monoclonal antibodies for therapy and molecular-based methods for diagnostics are required. Given the rarity of the disease, it would be useful to organise a small stockpile centrally for all EU countries and to maintain an inventory of DAT availability within and between countries.

Imaging tests in staging and surveillance of non-metastatic breast cancer: changes in routine clinical practice and cost implications.

PubMed

De Placido, S; De Angelis, C; Giuliano, M; Pizzi, C; Ruocco, R; Perrone, V; Bruzzese, D; Tommasielli, G; De Laurentiis, M; Cammarota, S; Arpino, G; Arpino, G

2017-03-14

Although guidelines do not recommend computerised tomography (CT), positron emission tomography (PET) or magnetic resonance imaging (MRI) for the staging or follow-up of asymptomatic patients with non-metastatic breast cancer, they are often requested in routine clinical practice. The aim of this study was to determine the staging and follow-up patterns, and relative costs in a large population of breast cancer patients living and treated in a Southern Italian region. We analysed the clinical computerised information recorded by 567 primary-care physicians assisting about 650 000 inhabitants in the Campania region. Patients with non-metastatic breast cancer were identified and divided into calendar years from 2001 to 2010. The number of diagnostic tests prescribed per 100 patients (N/Pts) and the mean cost per patient was determined 3 months before diagnosis and up to 1 year after diagnosis. Costs are expressed in constant 2011 euros. We identified 4680 newly diagnosed cases of asymptomatic non-metastatic breast cancer. N/Pts increased significantly (P<0.0001) from 2001 to 2010. The mean number of prescribed mammograms, bone scans, abdominal ultrasound and chest X-rays ('routine tests'), and costs was unchanged. However, the number of CT, PET scans and MRI ('new tests')prescriptions almost quadrupled and the mean cost per patient related to these procedures significantly increased from [euro ]357 in 2001 to [euro ]830 in 2010 (P<0.0001). New test prescriptions and relative costs significantly and steadily increased throughout the study period. At present there is no evidence that the delivery of new tests to asymptomatic patients improves breast cancer outcome. Well-designed clinical trials are urgently needed to shed light on the impact of these tests on clinical outcome and overall survival.

Evaluating the diagnostic accuracy of Arabic SNAP test for children with hypernasality.

PubMed

Abou-Elsaad, Tamer; Afsah, Omayma; Baz, Hemmat; Mansy, Alzahraa

2016-06-01

Nasometry is a method of measuring the acoustic correlates of resonance through a computer-based instrument called nasometer. High nasalance scores in comparison to normative data suggest hypernasality and/or other nasality disorders, while low scores suggest hyponasality. Normative values of nasalance for Egyptian Arabic speakers were established using the Arabic SNAP (Simplified Nasometric Assessment Procedures) test. to evaluate the diagnostic accuracy of Arabic SNAP test to allow for its use in the differentiation between normal and hypernasal speech in Egyptian Arabic-speaking children. Nasalance scores of normal children (n=92) on Arabic SNAP test were compared to those of 30 children with velopharyngeal insufficiency due to cleft palate. Receiver operating characteristic (ROC) curve was used to determine cutoff points with the highest sensitivity and specificity. Statistically significant differences were found between both groups for all items in nasometric evaluation (p<0.05) except for prolonged/m/sound (p>0.05). Cutoff points were determined and certain items were selected for routine nasometric evaluation. The Arabic SNAP test is a sensitive and specific tool for evaluation of children with hypernasality and can be used for both diagnosis and follow up of these cases. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

HPV Virus Transcriptional Status Assessment in a Case of Sinonasal Carcinoma.

PubMed

Ilardi, Gennaro; Russo, Daniela; Varricchio, Silvia; Salzano, Giovanni; Dell'Aversana Orabona, Giovanni; Napolitano, Virginia; Di Crescenzo, Rosa Maria; Borzillo, Alessandra; Martino, Francesco; Merolla, Francesco; Mascolo, Massimo; Staibano, Stefania

2018-03-16

Human Papilloma Virus (HPV) can play a causative role in the development of sinonasal tract malignancies. In fact, HPV may be the most significant causative agent implicated in sinonasal tumorigenesis and is implicated in as many as 21% of sinonasal carcinomas. To date, there are no definitive, reliable and cost-effective, diagnostic tests approved by the FDA for the unequivocal determination of HPV status in head and neck cancers. We followed an exhaustive algorithm to correctly test HPV infection, including a sequential approach with p16INK4a IHC, viral DNA genotyping and in situ hybridization for E6/E7 mRNA. Here, we report a case of sinonasal carcinoma with discordant results using HPV test assays. The tumor we describe showed an irregular immunoreactivity for p16INK4a, and it tested positive for HPV DNA; nevertheless, it was negative for HR-HPV mRNA. We discuss the possible meaning of this discrepancy. It would be advisable to test HPV transcriptional status of sinonasal carcinoma on a diagnostic routine basis, not only by p16INK4a IHC assay, but also by HPV DNA genotyping and HR-HPV mRNA assessment.

Diagnostic yield of a routine magnetic resonance imaging in tinnitus and clinical relevance of the anterior inferior cerebellar artery loops.

PubMed

Hoekstra, Carlijn E L; Prijs, Vera F; van Zanten, Gijsbert A

2015-02-01

To assess the diagnostic yield of a routine magnetic resonance imaging (MRI) scan in patients with (unilateral) chronic tinnitus, to define the frequency of incidental findings, and to assess the clinical relevance of potentially found anterior inferior cerebellar artery (AICA) loops. Retrospective cohort study. Tertiary Tinnitus Care Group at the University Medical Center Utrecht. Three hundred twenty-one patients with chronic tinnitus. Routine diagnostic magnetic resonance imaging (MRI) and diagnostic auditory brainstem responses (ABR) when an AICA loop was found. Relationship between abnormalities on MRI and tinnitus. In 138 patients (45%), an abnormality on the MRI scan was described. In only 7 patients (2.2%), the abnormality probably related to the patient's tinnitus. Results were not significantly better in patients with unilateral tinnitus (abnormalities in 3.2%). Incidental findings, not related to the tinnitus, were found in 41% of the patients. In 70 patients (23%), an AICA loop was found in the internal auditory canal. No significant relationships were found between the presence of an AICA loop and the side of the tinnitus, abnormalities on the ABR or complaints specific to nerve compression syndrome. A routine MRI is of little or no value in patients with tinnitus with persistent complaints. Anterior inferior cerebellar artery loops are often encountered on an MRI scan but rarely relate to the tinnitus and should thus be considered incidental findings. It is advised to only perform an MRI when on clinical grounds a specific etiology with tinnitus as the symptom seems probable.

Reagent and labor cost optimization through automation of fluorescence in situ hybridization (FISH) with the VP 2000: an Italian case study.

PubMed

Zanatta, Lucia; Valori, Laura; Cappelletto, Eleonora; Pozzebon, Maria Elena; Pavan, Elisabetta; Dei Tos, Angelo Paolo; Merkle, Dennis

2015-02-01

In the modern molecular diagnostic laboratory, cost considerations are of paramount importance. Automation of complex molecular assays not only allows a laboratory to accommodate higher test volumes and throughput but also has a considerable impact on the cost of testing from the perspective of reagent costs, as well as hands-on time for skilled laboratory personnel. The following study tracked the cost of labor (hands-on time) and reagents for fluorescence in situ hybridization (FISH) testing in a routine, high-volume pathology and cytogenetics laboratory in Treviso, Italy, over a 2-y period (2011-2013). The laboratory automated FISH testing with the VP 2000 Processor, a deparaffinization, pretreatment, and special staining instrument produced by Abbott Molecular, and compared hands-on time and reagent costs to manual FISH testing. The results indicated significant cost and time saving when automating FISH with VP 2000 when more than six FISH tests were run per week. At 12 FISH assays per week, an approximate total cost reduction of 55% was observed. When running 46 FISH specimens per week, the cost saving increased to 89% versus manual testing. The results demonstrate that the VP 2000 processor can significantly reduce the cost of FISH testing in diagnostic laboratories. © 2014 Society for Laboratory Automation and Screening.

Diagnostic Yield of Laboratory Methods and Value of Viral Genotyping during an Outbreak of Mumps in a Partially Vaccinated Population in British Columbia, Canada.

PubMed

Nunn, Alexandra; Masud, Shazia; Krajden, Mel; Naus, Monika; Jassem, Agatha N

2018-05-01

Mumps remains endemic in North America despite routine use of the measles, mumps, and rubella (MMR) vaccine. In 2016, an outbreak of mumps in British Columbia, Canada, provided an opportunity to determine the diagnostic utility of laboratory testing methods. Specimens from patients with clinical mumps were tested for infection using a commercial enzyme-linked immunosorbent assay (ELISA) for antibody detection and an in-house reverse transcriptase PCR (RT-PCR) targeting viral fusion and small hydrophobic (SH) genes. Viral genotyping was performed by SH gene sequencing. Laboratory data was linked with epidemiologic case data. Of the 139 confirmed cases, 94 (68%) had reported or documented history of MMR vaccination. Specimens were typically collected 1 day (for buccal and IgM tests) or 2 days (for urine tests) after symptom onset. Most confirmed cases (69%) were confirmed by buccal swab RT-PCR. Among cases tested by multiple methods, the percent positivity for buccal swab RT-PCR was 90% (96/107) compared to 43% (30/69) for both IgM ELISA and urine RT-PCR. Mumps IgM detection was higher in confirmed cases with no history of vaccination than in those with history (64% versus 34%, P = 0.02). The outbreak strain was identified as genotype G related to MuVi/Sheffield.GBR/1.05 but with conserved variations in five nucleotides within the SH gene that allowed linkage of geographically distinct cases. In conclusion, RT-PCR of buccal specimens had the highest diagnostic yield during a mumps outbreak in a partially vaccinated population. To optimize mumps diagnostic potential, clinicians should collect specimens depending on when the patient presents for care and their immunization history. © Crown copyright 2018.

UK NEQAS survey of allergen component testing across the United Kingdom and other European countries

PubMed Central

Saleem, R.; Keymer, C.; Patel, D.; Egner, W.

2017-01-01

Summary The clinical utility of molecular diagnostic approaches in allergy investigation is being recognized increasingly to play a significant role in the management of allergic patients. Determining the sensitization pattern, which is best achieved through the use of component resolved diagnostics (CRD), allows effective risk stratification, appropriate treatment and patient selection for immunotherapy. In order to assess the diagnostic service provisions for in‐vitro allergy testing across Europe, a survey was carried out via the total immunoglobulin (Ig)E and specific IgE external quality assurance schemes run by UK National External Quality Assessment Service (NEQAS) Immunology, Immunochemistry and Allergy. This survey assessed allergy testing, and in particular allergen components offered by the laboratories, and found a wide variability in service provision, particularly between the United Kingdom and other European Union (EU) countries. Furthermore, there was lack of standardization for acquisition of clinical information to aid allergen (and component) selection, gating strategy, testing algorithms and clinical interpretation. Interestingly, a significant proportion of laboratories (the majority from EU) stated that they ‘used’ the results for peanut components for risk stratification. However, the vast majority of participants were unaware of guidelines relating to the use of allergen component testing, and agreed that further education would assist in reaching a common platform. Hence, this survey has highlighted that although CRD has been adopted into routine diagnostics across Europe, it is potentially compromised by lack of standardized protocols and guidance sources. Consequently, there is a need for local or national standards and education through External Quality Assurance services on the performance and application of CRD into allergy investigation. PMID:28423454

New diagnostic methods for pneumonia in the ICU.

PubMed

Douglas, Ivor S

2016-04-01

Pneumonia leading to severe sepsis and critical illness including respiratory failure remains a common and therapeutically challenging diagnosis. Current clinical approaches to surveillance, early detection, and conventional culture-based microbiology are inadequate for optimal targeted antibiotic treatment and stewardship. Efforts to enhance diagnosis of community-acquired and health care-acquired pneumonia, including ventilator-associated pneumonia (VAP), are the focus of recent studies reviewed here. Newer surveillance definitions are sensitive for pneumonia in the ICU including VAP but consistently underdetect patients that are clinically shown to have bacterial VAP based on clinical diagnostic criteria and response to antibiotic treatment. Routinely measured plasma biomarkers, including procalcitonin and C-reactive protein, lack sufficient precision and predictive accuracy to inform diagnosis. Novel rapid microbiological diagnostics, including nucleic-acid amplification, mass spectrometry, and fluorescence microscopy-based technologies are promising approaches for the future. Exhaled breath biomarkers, including measurement of volatile organic compounds, represent a future approach. The integration of novel diagnostics for rapid microbial identification, resistance phenotyping, and antibiotic sensitivity testing into usual care practice could significantly transform the care of patients and potentially inform significantly improved targeted antimicrobial selection, de-escalation, and stewardship.

Experimental analysis of a novel and low-cost pin photodiode dosimetry system for diagnostic radiology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nazififard, Mohammad, E-mail: nazifi@kashanu.ac.ir; Mahmoudieh, Afshin; Suh, Kune Y.

Silicon PIN photodiode has recently found broad and exciting applications in the ionizing radiation dosimetry. In this study a compact and novel dosimetry system using a commercially available PIN photodiode (BPW34) has been experimentally tested for diagnostic radiology. The system was evaluated with clinical beams routinely used for diagnostic radiology and calibrated using a secondary reference standard. Measured dose with PIN photodiode (Air Kerma) varied from 10 to 430 μGy for tube voltages from 40 to 100 kVp and tube current from 0.4 to 40 mAs. The minimum detectable organ dose was estimated to be 10 μGy with 20% uncertainty.more » Results showed a linear correlation between the PIN photodiode readout and dose measured with standard dosimeters spanning doses received. The present dosimetry system having advantages of suitable sensitivity with immediate readout of dose values, low cost, and portability could be used as an alternative to passive dosimetry system such as thermoluminescent dosimeter for dose measurements in diagnostic radiology.« less

Translational HIV-1 research: from routine diagnostics to new virology insights in Amsterdam, the Netherlands during 1983-2013

PubMed Central

2013-01-01

An HIV-1 diagnostic laboratory was established in the Academic Medical Center (AMC) of the University of Amsterdam after the discovery of human immunodeficiency virus (HIV) as the cause of the acquired immunodeficiency syndrome (AIDS). The first AIDS patients were diagnosed here in 1981 and since 1983 we have tested the samples of 50992 patients using a variety of assays that greatly improved over the years. We will describe some of the basic results from this diagnostic laboratory and then focus on the spin-off in terms of the development of novel virus assays to detect super-infections and ultra-sensitive assays to measure the intracellular HIV-1 RNA load. We also review several original research findings in the field of HIV-1 virology that stem from initial observations made in the diagnostic unit. This includes the study of genetic defects in the HIV-1 genome and time trends of the replication fitness over 30 years of viral evolution, but also the description of novel HIV-1 variants in difficult-to-diagnose clinical specimen. PMID:23985078

Translational HIV-1 research: from routine diagnostics to new virology insights in Amsterdam, the Netherlands during 1983-2013.

PubMed

van der Kuyl, Antoinette C; Bakker, Margreet; Jurriaans, Suzanne; Back, Nicole K T; Pasternak, Alexander O; Cornelissen, Marion; Berkhout, Ben

2013-08-28

An HIV-1 diagnostic laboratory was established in the Academic Medical Center (AMC) of the University of Amsterdam after the discovery of human immunodeficiency virus (HIV) as the cause of the acquired immunodeficiency syndrome (AIDS). The first AIDS patients were diagnosed here in 1981 and since 1983 we have tested the samples of 50992 patients using a variety of assays that greatly improved over the years. We will describe some of the basic results from this diagnostic laboratory and then focus on the spin-off in terms of the development of novel virus assays to detect super-infections and ultra-sensitive assays to measure the intracellular HIV-1 RNA load. We also review several original research findings in the field of HIV-1 virology that stem from initial observations made in the diagnostic unit. This includes the study of genetic defects in the HIV-1 genome and time trends of the replication fitness over 30 years of viral evolution, but also the description of novel HIV-1 variants in difficult-to-diagnose clinical specimen.

Vanishing tattoo multi-sensor for biomedical diagnostics

NASA Astrophysics Data System (ADS)

Moczko, E.; Meglinski, I.; Piletsky, S.

2008-04-01

Currently, precise non-invasive diagnostics systems for the real-time multi detection and monitoring of physiological parameters and chemical analytes in the human body are urgently required by clinicians, physiologists and bio-medical researchers. We have developed a novel cost effective smart 'vanishing tattoo' (similar to temporary child's tattoos) consisting of environmental-sensitive dyes. Painlessly impregnated into the skin the smart tattoo is capable of generating optical/fluorescence changes (absorbance, transmission, reflectance, emission and/or luminescence within UV, VIS or NIR regions) in response to physical or chemical changes. These changes allow the identification of colour pattern changes similar to bar-code scanning. Such a system allows an easy, cheap and robust comprehensive detection of various parameters and analytes in a small volume of sample (e.g. variations in pH, temperature, ionic strength, solvent polarity, presence of redox species, surfactants, oxygen). These smart tattoos have possible applications in monitoring the progress of disease and transcutaneous drug delivery. The potential of this highly innovative diagnostic tool is wide and diverse and can impact on routine clinical diagnostics, general therapeutic management, skin care and cosmetic products testing as well as fundamental physiological investigations.

Vanishing "tattoo" multisensor for biomedical diagnostics

NASA Astrophysics Data System (ADS)

Moczko, E.; Meglinski, I.; Piletsky, S.

2008-02-01

Currently, precise non-invasive diagnostics systems for the real-time multi detection and monitoring of physiological parameters and chemical analytes in the human body are urgently required by clinicians, physiologists and bio-medical researchers. We have developed a novel cost effective smart 'vanishing tattoo' (similar to temporary child's tattoos) consisting of environmental-sensitive dyes. Painlessly impregnated into the skin the smart tattoo is capable of generating optical/fluorescence changes (absorbance, transmission, reflectance, emission and/or luminescence within UV, VIS or NIR regions) in response to physical or chemical changes. These changes allow the identification of colour pattern changes similar to bar-code scanning. Such a system allows an easy, cheap and robust comprehensive detection of various parameters and analytes in a small volume of sample (e.g. variations in pH, temperature, ionic strength, solvent polarity, presence of redox species, surfactants, oxygen). These smart tattoos have possible applications in monitoring the progress of disease and transcutaneous drug delivery. The potential of this highly innovative diagnostic tool is wide and diverse and can impact on routine clinical diagnostics, general therapeutic management, skin care and cosmetic products testing as well as fundamental physiological investigations.

The Health Technology Assessment of companion diagnostics: experience of NICE.

PubMed

Byron, Sarah K; Crabb, Nick; George, Elisabeth; Marlow, Mirella; Newland, Adrian

2014-03-15

Companion diagnostics are used to aid clinical decision making to identify patients who are most likely to respond to treatment. They are becoming increasingly important as more new pharmaceuticals receive licensed indications that require the use of a companion diagnostic to identify the appropriate patient subgroup for treatment. These pharmaceuticals have proven benefit in the treatment of some cancers and other diseases, and also have potential to precisely tailor treatments to the individual in the future. However, the increasing use of companion diagnostics could place a substantial burden on health system resources to provide potentially high volumes of testing. This situation, in part, has led policy makers and Health Technology Assessment (HTA) bodies to review the policies and methods used to make reimbursement decisions for pharmaceuticals requiring companion diagnostics. The assessment of a pharmaceutical alongside the companion diagnostic used in the clinical trials may be relatively straightforward, although there are a number of challenges associated with assessing pharmaceuticals where a range of alternative companion diagnostics are available for use in routine clinical practice. The UK HTA body, the National Institute for Health and Care Excellence (NICE), has developed policy for considering companion diagnostics using its Technology Appraisal and Diagnostics Assessment Programs. Some HTA bodies in other countries have also adapted their policies and methods to accommodate the assessment of companion diagnostics. Here, we provide insight into the HTA of companion diagnostics for reimbursement decisions and how the associated challenges are being addressed, in particular by NICE. See all articles in this CCR Focus section, "The Precision Medicine Conundrum: Approaches to Companion Diagnostic Co-development." ©2014 AACR.

A Ribeiroia spp. (Class: Trematoda) - Specific PCR-based diagnostic

USGS Publications Warehouse

Reinitz, David M.; Yoshino, T.P.; Cole, Rebecca A.

2007-01-01

Increased reporting of amphibian malformations in North America has been noted with concern in light of reports that amphibian numbers and species are declining worldwide. Ribeiroia ondatrae has been shown to cause a variety of types of malformations in amphibians. However, little is known about the prevalence of R. ondatrae in North America. To aid in conducting field studies of Ribeiroia spp., we have developed a polymerase chain reaction (PCR)-based diagnostic. Herein, we describe the development of an accurate, rapid, simple, and cost-effective diagnostic for detection of Ribeiroia spp. infection in snails (Planorbella trivolvis). Candidate oligonucleotide primers for PCR were designed via DNA sequence analyses of multiple ribosomal internal transcribed spacer-2 regions from Ribeiroia spp. and Echinostoma spp. Comparison of consensus sequences determined from both genera identified areas of sequence potentially unique to Ribeiroia spp. The PCR reliably produced a diagnostic 290-base pair (bp) product in the presence of a wide concentration range of snail or frog DNA. Sensitivity was examined with DNA extracted from single R. ondatrae cercaria. The single-tube PCR could routinely detect less than 1 cercariae equivalent, because DNA isolated from a single cercaria could be diluted at least 1:50 and still yield a positive result via gel electrophoresis. An even more sensitive nested PCR also was developed that routinely detected 100 fg of the 290-bp fragment. The assay did not detect furcocercous cercariae of certain Schistosomatidae, Echinostoma sp., or Sphaeridiotrema globulus nor adults of Clinostomum sp. or Cyathocotyle bushiensis. Field testing of 137 P. trivolvis identified 3 positives with no overt environmental cross-reactivity, and results concurred with microscopic examinations in all cases. ?? American Society of Parasitologists 2007.

Atypical Ewing sarcoma breakpoint region 1 fluorescence in-situ hybridization signal patterns in bone and soft tissue tumours: diagnostic experience with 135 cases.

PubMed

Vargas, A Cristina; Selinger, Christina I; Satgunaseelan, Laveniya; Cooper, Wendy A; Gupta, Ruta; Stalley, Paul; Brown, Wendy; Soper, Judy; Schatz, Julie; Boyle, Richard; Thomas, David M; Tattersall, Martin H N; Bhadri, Vivek A; Maclean, Fiona; Bonar, S Fiona; Scolyer, Richard A; Karim, Rooshdiya Z; McCarthy, Stanley W; Mahar, Annabelle; O'Toole, Sandra A

2016-12-01

Recurrent Ewing sarcoma breakpoint region 1 (EWSR1) gene rearrangements characterize a select group of bone and soft tissue tumours. In our routine diagnostic practice with fluorescence in-situ hybridization (FISH), we have occasionally observed EWSR1 gene rearrangements in tumours not associated classically with EWSR1 translocations. This study aimed to review our institutional experience of this phenomenon and also to highlight the occurrence of unusual EWSR1 FISH signals (i.e. 5' centromeric region or 3' telomeric region signals) that do not fulfil the published diagnostic criteria for rearrangements. Using an EWSR1 break-apart probe, we performed FISH assays on formalin-fixed paraffin-embedded tissue sections from 135 bone and soft tissue specimens as part of their routine diagnostic work-up. EWSR1 gene rearrangements were identified in 51% of cases, 56% of which also showed an abnormal FISH signal pattern (in addition to classically rearranged signals). However, atypical FISH signals were present in 45% of the non-rearranged cases. In addition, we observed tumours unrelated to those described classically as EWSR1-associated that were technically EWSR1-rearranged in 6% of cases. Borderline levels of rearrangement (affecting 10-30% of lesional cells) were present in an additional 17% of these cases. While our study confirmed that FISH is a sensitive and specific tool in the diagnosis of EWSR1-associated tumours, atypical FISH signals and classical rearrangement in entities other than EWSR1-associated tumours can occur. Therefore, it is essential that the FISH result not be used as an isolated test, but must be evaluated in the context of clinical features, imaging, pathological and immunohistochemical findings. © 2016 John Wiley & Sons Ltd.

A novel metric that quantifies risk stratification for evaluating diagnostic tests: The example of evaluating cervical-cancer screening tests across populations.

PubMed

Katki, Hormuzd A; Schiffman, Mark

2018-05-01

Our work involves assessing whether new biomarkers might be useful for cervical-cancer screening across populations with different disease prevalences and biomarker distributions. When comparing across populations, we show that standard diagnostic accuracy statistics (predictive values, risk-differences, Youden's index and Area Under the Curve (AUC)) can easily be misinterpreted. We introduce an intuitively simple statistic for a 2 × 2 table, Mean Risk Stratification (MRS): the average change in risk (pre-test vs. post-test) revealed for tested individuals. High MRS implies better risk separation achieved by testing. MRS has 3 key advantages for comparing test performance across populations with different disease prevalences and biomarker distributions. First, MRS demonstrates that conventional predictive values and the risk-difference do not measure risk-stratification because they do not account for test-positivity rates. Second, Youden's index and AUC measure only multiplicative relative gains in risk-stratification: AUC = 0.6 achieves only 20% of maximum risk-stratification (AUC = 0.9 achieves 80%). Third, large relative gains in risk-stratification might not imply large absolute gains if disease is rare, demonstrating a "high-bar" to justify population-based screening for rare diseases such as cancer. We illustrate MRS by our experience comparing the performance of cervical-cancer screening tests in China vs. the USA. The test with the worst AUC = 0.72 in China (visual inspection with acetic acid) provides twice the risk-stratification (i.e. MRS) of the test with best AUC = 0.83 in the USA (human papillomavirus and Pap cotesting) because China has three times more cervical precancer/cancer. MRS could be routinely calculated to better understand the clinical/public-health implications of standard diagnostic accuracy statistics. Published by Elsevier Inc.

Selective versus routine patch metal allergy testing to select bar material for the Nuss procedure in 932 patients over 10years.

PubMed

Obermeyer, Robert J; Gaffar, Sheema; Kelly, Robert E; Kuhn, M Ann; Frantz, Frazier W; McGuire, Margaret M; Paulson, James F; Kelly, Cynthia S

2018-02-01

The aim of the study was to determine the role of patch metal allergy testing to select bar material for the Nuss procedure. An IRB-approved (11-04-WC-0098) single institution retrospective, cohort study comparing selective versus routine patch metal allergy testing to select stainless steel or titanium bars for Nuss repair was performed. In Cohort A (9/2004-1/2011), selective patch testing was performed based on clinical risk factors. In Cohort B (2/2011-9/2014), all patients were patch tested. The cohorts were compared for incidence of bar allergy and resultant premature bar loss. Risk factors for stainless steel allergy or positive patch test were evaluated. Cohort A had 628 patients with 63 (10.0%) selected for patch testing, while all 304 patients in Cohort B were tested. Over 10years, 15 (1.8%) of the 842 stainless steel Nuss repairs resulted in a bar allergy, and 5 had a negative preoperative patch test. The incidence of stainless steel bar allergy (1.8% vs 1.7%, p=0.57) and resultant bar loss (0.5% vs 1.3%, p=0.23) was not statistically different between cohorts. An allergic reaction to a stainless steel bar or a positive patch test was more common in females (OR=2.3, p<0.001) and patients with a personal (OR=24.8, p<0.001) or family history (OR=3.1, p<0.001) of metal sensitivity. Stainless steel bar allergies occur at a low incidence with either routine or selective patch metal allergy testing. If selective testing is performed, it is advisable in females and patients with a personal or family history of metal sensitivity. A negative preoperative patch metal allergy test does not preclude the possibility of a postoperative stainless steel bar allergy. Level III Treatment Study and Study of Diagnostic Test. Copyright © 2017 Elsevier Inc. All rights reserved.

From autoantibody research to standardized diagnostic assays in the management of human diseases - report of the 12th Dresden Symposium on Autoantibodies.

PubMed

Conrad, K; Andrade, L E C; Chan, E K L; Mahler, M; Meroni, P L; Pruijn, G J M; Steiner, G; Shoenfeld, Y

2016-07-01

Testing for autoantibodies (AABs) is becoming more and more relevant, not only for diagnosing autoimmune diseases (AIDs) but also for the differentiation of defined AID subtypes with different clinical manifestations, course and prognosis as well as the very early diagnosis for adequate management in the context of personalized medicine. A major challenge to improve diagnostic accuracy is to harmonize or even standardize AAB analyses. This review presents the results of the 12th Dresden Symposium on Autoantibodies that focused on several aspects of improving autoimmune diagnostics. Topics that are addressed include the International Consensus on ANA Patterns (ICAP) and the International Autoantibody Standardization (IAS) initiatives, the optimization of diagnostic algorithms, the description and evaluation of novel disease-specific AABs as well as the development and introduction of novel assays into routine diagnostics. This review also highlights important developments of recent years, most notably the improvement in diagnosing and predicting the course of rheumatoid arthritis, systemic sclerosis, idiopathic inflammatory myopathies, and of autoimmune neurological, gastrointestinal and liver diseases; the potential diagnostic role of anti-DFS70 antibodies and tumor-associated AABs. Furthermore, some hot topics in autoimmunity regarding disease pathogenesis and management are described. © The Author(s) 2016.

Standardization of Laboratory Methods for the PERCH Study

PubMed Central

Karron, Ruth A.; Morpeth, Susan C.; Bhat, Niranjan; Levine, Orin S.; Baggett, Henry C.; Brooks, W. Abdullah; Feikin, Daniel R.; Hammitt, Laura L.; Howie, Stephen R. C.; Knoll, Maria Deloria; Kotloff, Karen L.; Madhi, Shabir A.; Scott, J. Anthony G.; Thea, Donald M.; Adrian, Peter V.; Ahmed, Dilruba; Alam, Muntasir; Anderson, Trevor P.; Antonio, Martin; Baillie, Vicky L.; Dione, Michel; Endtz, Hubert P.; Gitahi, Caroline; Karani, Angela; Kwenda, Geoffrey; Maiga, Abdoul Aziz; McClellan, Jessica; Mitchell, Joanne L.; Morailane, Palesa; Mugo, Daisy; Mwaba, John; Mwansa, James; Mwarumba, Salim; Nyongesa, Sammy; Panchalingam, Sandra; Rahman, Mustafizur; Sawatwong, Pongpun; Tamboura, Boubou; Toure, Aliou; Whistler, Toni; O’Brien, Katherine L.; Murdoch, David R.

2017-01-01

Abstract The Pneumonia Etiology Research for Child Health study was conducted across 7 diverse research sites and relied on standardized clinical and laboratory methods for the accurate and meaningful interpretation of pneumonia etiology data. Blood, respiratory specimens, and urine were collected from children aged 1–59 months hospitalized with severe or very severe pneumonia and community controls of the same age without severe pneumonia and were tested with an extensive array of laboratory diagnostic tests. A standardized testing algorithm and standard operating procedures were applied across all study sites. Site laboratories received uniform training, equipment, and reagents for core testing methods. Standardization was further assured by routine teleconferences, in-person meetings, site monitoring visits, and internal and external quality assurance testing. Targeted confirmatory testing and testing by specialized assays were done at a central reference laboratory. PMID:28575358

Phase Contrast Microscopy Analysis of Breast Tissue

PubMed Central

Wells, Wendy A.; Wang, Xin; Daghlian, Charles P.; Paulsen, Keith D.; Pogue, Brian W.

2010-01-01

OBJECTIVE To assess how optical scatter properties in breast tissue, as measured by phase contrast microscopy and interpreted pathophysiologically, might be exploited as a diagnostic tool to differentiate cancer from benign tissue. STUDY DESIGN We evaluated frozen human breast tissue sections of adipose tissue, normal breast parenchyma, benign fibroadenoma tumors and noninvasive and invasive malignant cancers by phase contrast microscopy through quantification of grayscale values, using multiple regions of interest (ROI). Student’s t tests were performed on phase contrast measures across diagnostic categories testing data from individual cases; all ROI data were used as separate measures. RESULTS Stroma demonstrated significantly higher scatter intensity than did epithelium, with lower scattering in tumor-associated stroma as compared with normal or benign-associated stroma. Measures were comparable for invasive and noninvasive malignant tumors but were higher than those found in benign tumors and were lowest in adipose tissue. CONCLUSION Significant differences were found in scatter coefficient properties of epithelium and stroma across diagnostic categories of breast tissue, particularly between benign and malignant-associated stroma. Improved understanding of how scatter properties correlate with morphologic criteria used in routine pathologic diagnoses could have a significant clinical impact as developing optical technology allows macroscopic in situ phase contrast imaging. PMID:19736867

System Design and Development of a Robotic Device for Automated Venipuncture and Diagnostic Blood Cell Analysis.

PubMed

Balter, Max L; Chen, Alvin I; Fromholtz, Alex; Gorshkov, Alex; Maguire, Tim J; Yarmush, Martin L

2016-10-01

Diagnostic blood testing is the most prevalent medical procedure performed in the world and forms the cornerstone of modern health care delivery. Yet blood tests are still predominantly carried out in centralized labs using large-volume samples acquired by manual venipuncture, and no end-to-end solution from blood draw to sample analysis exists today. Our group is developing a platform device that merges robotic phlebotomy with automated diagnostics to rapidly deliver patient information at the site of the blood draw. The system couples an image-guided venipuncture robot, designed to address the challenges of routine venous access, with a centrifuge-based blood analyzer to obtain quantitative measurements of hematology. In this paper, we first present the system design and architecture of the integrated device. We then perform a series of in vitro experiments to evaluate the cannulation accuracy of the system on blood vessel phantoms. Next, we assess the effects of vessel diameter, needle gauge, flow rate, and viscosity on the rate of sample collection. Finally, we demonstrate proof-of-concept of a white cell assay on the blood analyzer using in vitro human samples spiked with fluorescently labeled microbeads.

Diagnosis of growth hormone deficiency in the paediatric and transitional age.

PubMed

Chinoy, A; Murray, P G

2016-12-01

Growth hormone deficiency is a rare cause of childhood short stature, but one for which treatment exists in the form of recombinant human growth hormone. A diagnosis of growth hormone deficiency is made based on auxology, biochemistry and imaging. Although no diagnostic gold standard exists, growth hormone provocation tests are considered the mainstay of diagnostic investigations. However, these must be interpreted with caution in view of issues with variability and reproducibility, as well as the limited evidence-base for cut-off values used to distinguish growth hormone deficient and non-growth hormone deficient subjects. In addition, nutritional and pubertal status can affect results, with no consensus on the role of priming with sex steroid hormones. Difficulties with assays exist both for growth hormone as well as insulin-like growth factor-1. Pituitary magnetic resonance imaging is a useful diagnostic, and possibly prognostic, aid. Although genetic testing is not routine, the discovery of more relevant mutations makes it an increasingly important investigation. Children with growth hormone deficiency are retested biochemically on completion of growth, to assess whether they remain so into adulthood. Copyright © 2016. Published by Elsevier Ltd.

Novel PCRs for differential diagnosis of cestodes.

PubMed

Roelfsema, Jeroen H; Nozari, Nahid; Pinelli, Elena; Kortbeek, Laetitia M

2016-02-01

Cestodes or tapeworms belong to a diverse group of helminths. The adult Taenia saginata and Taenia solium tapeworm can infest the human gut and the larval stage of Echinococcus spp. and T. solium can infect tissues of the human body, causing serious disease. Molecular diagnostics can be performed on proglottids, eggs and on cyst fluids taken by biopsy. Detection of cestodes when a helminthic infection is suspected is of vital importance and species determination is required for appropriate patient care. For routine diagnostics a single test that is able to detect and type a range of cestodes is preferable. We sought to improve our diagnostic procedure that used to rely on PCR and subsequent sequencing of the Cox1 and Nad1 genes. We have compared these PCRs with novel PCRs on the 12S rRNA and Nad5 gene and established the sensitivity and specificity. A single PCR on the 12S gene proved to be very suitable for detection and specification of Taenia sp. and Echinococcus sp. Both targets harbour enough polymorphic sites to determine the various Echinococcus species. The 12S PCR was most sensitive of all tested. Copyright © 2015 Elsevier Inc. All rights reserved.

Relationship between histopathological changes in post partum renal biopsies and renal function tests of African women with early onset pre-eclampsia.

PubMed

Khedun, S M; Naicker, T; Moodley, J

2000-05-01

To improve the diagnostic accuracy of concurrent renal disease in hypertension of pregnancy, biopsy evaluation is essential. In addition, establishing underlying renal disease is important for prognosis on future pregnancies. We therefore designed a study to determine the diagnostic yield of postpartum renal biopsy and the nature and frequency of complications associated with this procedure. Also, to determine relationships, if any, between renal function tests and ultrastructural and histopathological findings. Fifty renal biopsies were performed in the immediate postpartum period in black African women with early onset pre-eclampsia. Each biopsy specimen was placed in a separate container and coded so that sampling was unknown to the electron microscopist. Each biopsy specimen was divided into three parts, and processed and stained for light, fluorescent and transmission electron microscopy using conventional techniques. Renal tissue biopsies were adequate for diagnostic purposes in all cases. There were no complications in any of the 50 patients studied. Ultrastructural examination confirmed the light microscopy findings. In addition the ultrastructural findings showed intramembranous deposits, foot process fusion and mesangial deposits. In 16 patients with normal renal function tests; the biopsies evaluation from these patients showed ultrastructural changes. In the remaining 34 patients with abnormal renal function tests of varying severity; biopsy evaluation from these patients showed both ultrastructural and histopathological changes. Renal biopsy procedure is safe, and ultrastructural and histological findings obtained from postpartum renal biopsies are more informative than the routine renal function tests.

Amplified Detection of Prions and Other Amyloids by RT-QuIC in Diagnostics and the Evaluation of Therapeutics and Disinfectants.

PubMed

Caughey, Byron; Orru, Christina D; Groveman, Bradley R; Hughson, Andrew G; Manca, Matteo; Raymond, Lynne D; Raymond, Gregory J; Race, Brent; Saijo, Eri; Kraus, Allison

2017-01-01

Among the most sensitive, specific and practical of methods for detecting prions are the real-time quaking-induced conversion (RT-QuIC) assays. These assays exploit the fundamental self-propagating activity of prions to amplify the presence of prion seeds by as much as a trillion-fold. The reactions can detect most of the known mammalian prion diseases, often with sensitivities greater than those of animal bioassays. RT-QuIC assays are performed in multiwell plates with fluorescence detection and have now reached the sensitivity and practicality required for routine prion disease diagnostics. Some key strains of prions within particular host species, e.g., humans, cattle, and sheep, can be discriminated by comparison of RT-QuIC responses with different recombinant prion protein substrates. The most thoroughly validated diagnostic application of RT-QuIC is in the diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) using cerebrospinal fluid. Diagnostic sensitivities as high as 96% can be achieved in less than 24h with specificities of 98%-100%. The ability, if needed, to also test nasal swab samples can increase the RT-QuIC sensitivity for sCJD to virtually 100%. In addition to diagnostic applications, RT-QuIC has also been used in the testing of prion disinfectants and potential therapeutics. Mechanistically related assays are also now being developed for other protein misfolding diseases. © 2017 Elsevier Inc. All rights reserved.

Allergy to kiwi: is component-resolved diagnosis in routine clinical practice really impossible?

PubMed

Asero, R

2012-04-01

Kiwi allergy is frequent and can be the result of sensitization to a number of allergens showing different physicochemical characteristics. Component-resolved diagnosis of kiwi allergy is still unavailable in routine clinical practice. To investigate whether component resolved-diagnosis of kiwi allergy can be, at least in part, carried out by a proper combination of routinely available diagnostic tools. 63 adults with plant food allergy were studied 36 were kiwi-allergic while 27 were kiwi-tolerant and served as controls. Patients and controls underwent SPT with commercial peach and kiwi extracts, and with aprofilin-enriched date palm pollen extract (all by ALK-Abellò), and the measurement of IgE to birch, kiwi, and natural rubber latex. The in-vitro test showed poor sensitivity and specificity, as it scored positive in about 50% of patients and controls irrespective of clinical allergy to kiwi. The kiwi SPT showed overall poor sensitivity; however, it scored negative in all subjects with pollen food-allergy syndrome, was weakly positive in some lipid transfer protein-hypersensitive/kiwi tolerant subjects and in one latex-sensitized subject, and strongly positive in all subjects with primary kiwi sensitization. SPT with this commercial kiwi extract sensitively and specifically detects patients reacting to specific kiwi allergens. This can be useful to detect patients that are at risk of potentially severe reactions, particularly in case of co-sensitization to labile allergens, while we wait that the whole spectrum of kiwi allergens becomes available for routine in-vitro testing.

Scheme for the selection of measurement uncertainty models in blood establishments' screening immunoassays.

PubMed

Pereira, Paulo; Westgard, James O; Encarnação, Pedro; Seghatchian, Jerard; de Sousa, Gracinda

2015-02-01

Blood establishments routinely perform screening immunoassays to assess safety of the blood components. As with any other screening test, results have an inherent uncertainty. In blood establishments the major concern is the chance of false negatives, due to its possible impact on patients' health. This article briefly reviews GUM and diagnostic accuracy models for screening immunoassays, recommending a scheme to support the screening laboratories' staffs on the selection of a model considering the intended use of the screening results (i.e., post-transfusion safety). The discussion is grounded on a "risk-based thinking", risk being considered from the blood donor selection to the screening immunoassays. A combination of GUM and diagnostic accuracy models to evaluate measurement uncertainty in blood establishments is recommended. Copyright © 2014 Elsevier Ltd. All rights reserved.

Status epilepticus in dogs and cats, part 1: etiopathogenesis, epidemiology, and diagnosis.

PubMed

Blades Golubovic, Susan; Rossmeisl, John H

2017-05-01

To review current knowledge of the etiopathogenesis, diagnosis, and consequences of status epilepticus (SE) in veterinary patients. Human and veterinary literature, including clinical and laboratory research and reviews. Status epilepticus is a common emergency in dogs and cats, and may be the first manifestation of a seizure disorder. It results from the failure of termination of an isolated seizure. Multiple factors are involved in SE, including initiation and maintenance of neuronal excitability, neuronal network synchronization, and brain microenvironmental contributions to ictogenesis. Underlying etiologies of epilepsy and SE in dogs and cats are generally classified as genetic (idiopathic), structural-metabolic, or unknown. Diagnosis of convulsive SE is usually made based on historical information and the nature of the seizures. Patient specific variables, such as the history, age of seizure onset, and physical and interictal neurological examination findings can help hone the rule out list, and are used to guide selection and prioritization of diagnostic tests. Electroencephalographic monitoring is routinely used in people to diagnose SE and guide patient care decisions, but is infrequently performed in veterinary medicine. Nonconvulsive status epilepticus has been recognized in veterinary patients; routine electroencephalography would aid in the diagnosis of this phenomenon in dogs and cats. Status epilepticus is a medical emergency that can result in life-threatening complications involving the brain and systemic organs. Status epilepticus often requires comprehensive diagnostic testing, treatment with multiple anticonvulsant agents, and intensive supportive care. © Veterinary Emergency and Critical Care Society 2017.

Occurrence of nonspecific reactions among stool specimens tested by the Abbott TestPack rotavirus enzyme immunoassay.

PubMed Central

Lipson, S M; Leonardi, G P; Salo, R J; Schutzbank, T E; Kaplan, M H

1990-01-01

Sixty-five stool specimens obtained from children suffering from gastroenteritis were tested for the presence of antigen to rotavirus by the Abbott TestPack Rotavirus (TestPack) enzyme immunoassay kit. The Kallestad Pathfinder enzyme immunoassay, polyacrylamide gel electrophoresis, immune electron microscopy, and virus isolation were utilized as reference assays. Fifty-four specimens were in accord by TestPack and Kallestad Pathfinder. Among 11 discordant specimens positive with TestPack but negative by Kallestad Pathfinder, rotavirus was not identified by polyacrylamide gel electrophoresis, immune electron microscopy, or isolation in primary African green monkey kidney cell cultures. TestPack displayed a performance specificity of 83%. The inordinately high number of stool specimens reported as false-positive by TestPack precludes the incorporation of this antigen detection kit into our routine regimen of diagnostic virologic testing. Images PMID:2166074

Establishing diagnostic cut-off criteria for the COBAS AmpliPrep/COBAS TaqMan HIV-1 Qualitative test through validation against the Amplicor DNA test v1.5 for infant diagnosis using dried blood spots.

PubMed

Maritz, Jean; Preiser, Wolfgang; van Zyl, Gert U

2012-02-01

As antibody testing cannot confirm HIV-1 infection in children less than 18 months of age, diagnosis in these children depends on nucleic acid testing. The COBAS(®) AmpliPrep/COBAS(®) TaqMan(®) (CAP/CTM, Roche(®) Molecular Systems, Inc., Branchburg, NJ) HIV-1 Qualitative test is a total nucleic acid real-time PCR assay utilising whole EDTA blood or dried blood spots (DBS), which recently replaced the Roche(®) AMPLICOR(®) DNA test v1.5 (Amplicor) as the diagnostic HIV PCR assay in many South African laboratories. For the Amplicor assay, stringent diagnostic criteria were previously formulated for the local population, and a comparison reported the CAP/CTM's sensitivity at 99.7% and specificity at 100% for both sample types compared to these Amplicor criteria. To validate the assay prior to introduction in our laboratory and to define stringent diagnostic cut-off criteria. Whole EDTA blood samples from patients younger than 18 months sent for routine HIV-1 diagnosis were tested by Amplicor, and positive results were confirmed from DBS. CAP/CTM assays were subsequently performed from DBS. The CAP/CTM had a sensitivity of 98.8% and a specificity of 97.1%, but a positive predictive value (PPV) of only 78.7% compared to the Amplicor assay. Samples positive by CAP/CTM but negative by Amplicor displayed poor amplification curves compared to concordant positive samples. Upon re-testing those with sufficient material available by CAP/CTM, all showed negative results. The decreased PPV may either be due to false positive CAP/CTM results, or increased sensitivity compared to the Amplicor assay. Criteria were formulated for defining presumed false-positive results. Copyright © 2011 Elsevier B.V. All rights reserved.

Disease management of dairy calves and heifers.

PubMed

McGuirk, Sheila M

2008-03-01

This article focuses on the most important diseases of dairy calves and heifers and presents clinical approaches that can improve detection, diagnosis, and treatment of herd-based problems. A systematic herd investigation strategy is pivotal to define the problems, understand important risk factors, develop a plan, and make recommendations for disease management accurately. A review of records, colostrum and feeding routines, housing and bedding management, routine procedures, vaccination, and treatment protocols begins the investigation and determines which diagnostic procedures and testing strategies are most useful. Disease management is most effective when the problem source is well defined and the exposure can be limited, calf immunity can be enhanced, or a combination of both. Screening examinations performed regularly or done at strategic time points improves detection of disease, can be used to monitor treatment outcomes, and can avoid disease outbreaks.

Virtual Resting Pd/Pa From Coronary Angiography and Blood Flow Modelling: Diagnostic Performance Against Fractional Flow Reserve.

PubMed

Papafaklis, Michail I; Muramatsu, Takashi; Ishibashi, Yuki; Bourantas, Christos V; Fotiadis, Dimitrios I; Brilakis, Emmanouil S; Garcia-Garcia, Héctor M; Escaned, Javier; Serruys, Patrick W; Michalis, Lampros K

2018-03-01

Fractional flow reserve (FFR) has been established as a useful diagnostic tool. The distal coronary pressure to aortic pressure (Pd/Pa) ratio at rest is a simpler physiologic index but also requires the use of the pressure wire, whereas recently proposed virtual functional indices derived from coronary imaging require complex blood flow modelling and/or are time-consuming. Our aim was to test the diagnostic performance of virtual resting Pd/Pa using routine angiographic images and a simple flow model. Three-dimensional quantitative coronary angiography (3D-QCA) was performed in 139 vessels (120 patients) with intermediate lesions assessed by FFR. The resting Pd/Pa for each lesion was assessed by computational fluid dynamics. The discriminatory power of virtual resting Pd/Pa against FFR (reference: ≤0.80) was high (area under the receiver operator characteristic curve [AUC]: 90.5% [95% CI: 85.4-95.6%]). Diagnostic accuracy, sensitivity and specificity for the optimal virtual resting Pd/Pa cut-off (≤0.94) were 84.9%, 90.4% and 81.6%, respectively. Virtual resting Pd/Pa demonstrated superior performance (p<0.001) versus 3D-QCA %area stenosis (AUC: 77.5% [95% CI: 69.8-85.3%]). There was a good correlation between virtual resting Pd/Pa and FFR (r=0.69, p<0.001). Virtual resting Pd/Pa using routine angiographic data and a simple flow model provides fast functional assessment of coronary lesions without requiring the pressure-wire and hyperaemia induction. The high diagnostic performance of virtual resting Pd/Pa for predicting FFR shows promise for using this simple/fast virtual index in clinical practice. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Routine failures in the process for blood testing and the communication of results to patients in primary care in the UK: a qualitative exploration of patient and provider perspectives

PubMed Central

Litchfield, Ian; Bentham, Louise; Hill, Ann; McManus, Richard J; Lilford, Richard; Greenfield, Sheila

2015-01-01

Background The testing and result communication process in primary care is complex. Its successful completion relies on the coordinated efforts of a range of staff in primary care and external settings working together with patients. Despite the importance of diagnostic testing in provision of care, this complexity renders the process vulnerable in the face of increasing demand, stretched resources and a lack of supporting guidance. Methods We conducted a series of focus groups with patients and staff across four primary care practices using process-improvement strategies to identify and understand areas where either unnecessary delay is introduced, or the process may fail entirely. We then worked with both patients and staff to arrive at practical strategies to improve the current system. Results A total of six areas across the process were identified where improvements could be introduced. These were: (1) delay in phlebotomy, (2) lack of a fail-safe to ensure blood tests are returned to practices and patients, (3) difficulties in accessing results by telephone, (4) role of non-clinical staff in communicating results, (5) routine communication of normal results and (6) lack of a protocol for result communication. Conclusions A number of potential failures in testing and communicating results to patients were identified, and some specific ideas for improving existing systems emerged. These included same-day phlebotomy sessions, use of modern technology methods to proactively communicate routine results and targeted training for receptionists handling sensitive data. There remains an urgent need for further work to test these and other potential solutions. PMID:26251507

Routine failures in the process for blood testing and the communication of results to patients in primary care in the UK: a qualitative exploration of patient and provider perspectives.

PubMed

Litchfield, Ian; Bentham, Louise; Hill, Ann; McManus, Richard J; Lilford, Richard; Greenfield, Sheila

2015-11-01

The testing and result communication process in primary care is complex. Its successful completion relies on the coordinated efforts of a range of staff in primary care and external settings working together with patients. Despite the importance of diagnostic testing in provision of care, this complexity renders the process vulnerable in the face of increasing demand, stretched resources and a lack of supporting guidance. We conducted a series of focus groups with patients and staff across four primary care practices using process-improvement strategies to identify and understand areas where either unnecessary delay is introduced, or the process may fail entirely. We then worked with both patients and staff to arrive at practical strategies to improve the current system. A total of six areas across the process were identified where improvements could be introduced. These were: (1) delay in phlebotomy, (2) lack of a fail-safe to ensure blood tests are returned to practices and patients, (3) difficulties in accessing results by telephone, (4) role of non-clinical staff in communicating results, (5) routine communication of normal results and (6) lack of a protocol for result communication. A number of potential failures in testing and communicating results to patients were identified, and some specific ideas for improving existing systems emerged. These included same-day phlebotomy sessions, use of modern technology methods to proactively communicate routine results and targeted training for receptionists handling sensitive data. There remains an urgent need for further work to test these and other potential solutions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

When a patient suspected with juvenile idiopathic arthritis turns out to be diagnosed with an infectious disease - a review of Lyme arthritis in children.

PubMed

Orczyk, Krzysztof; Świdrowska-Jaros, Joanna; Smolewska, Elżbieta

2017-05-08

The Lyme arthritis is a common manifestation of infection with Borrelia burgdorferi spirochete. Despite its infectious background, the inflammation clinically and histopatologically resembles juvenile idiopathic arthritis. As it affects a considerable number of Lyme disease patients, it should be routinely considered in differential diagnosis. Development of arthritis is partially dependent on spirochetal factors, including the ribosomal spacer type and the sequence of outer surface protein C. Immunological background involves Th1-related response, but IL-17 provides an additional route of developing arthritis. Autoimmune mechanisms may lead to antibiotic-refractory arthritis. The current diagnostic standard is based on a 2-step testing: ELISA screening and immunoblot confirmation. Other suggested methods contain modified two-tier test with C6 ELISA instead of immunoblot. An initial 28-day course of oral antibiotics (doxycycline, cefuroxime axetil or amoxicillin) is a recommended treatment. Severe cases require further anti-inflammatory management. Precise investigation of new diagnostic and therapeutic approaches is advisable.

An Integrated Cardiology Patient Management System

PubMed Central

Kiely, F. Michael

1988-01-01

An integrated clinical database has been developed for all diagnostic cardiac services at Vancouver General Hospital. The system is installed on a Data General MV/10000 computer and utilizes the Flagship Application Generator from EPIC Systems Corp. Clinical information, as well as demographic and administrative data, is collected. The system features a custom menu for each user, whose selections provide direct access to the desired functional modules. The intention is to collect data from all the diagnostic areas of the Division of Cardiology, viz., Cardiac Ultrasound, Cardiac Catheterization Laboratory, Pacemaker Clinic and Electrocardiology (including 24 hour ambulatory EKGs and exercise testing). Automated links to the hospital's Admitting/Discharge/Transfer and Billing/Accounts Receivable systems have been implemented over the hospital's local area network. The system is used to produce routine reports of test results, patient billings, and departmental workload statistics. Inquiry functions permit the rapid location of patient records and produce an integrated profile of cardiology activity. In addition, selective searches of the data are available for research and/or other purposes.

Avian botulism and avian chlamydiosis in wild water birds, Benton Lake National Wildlife Refuge, Montana, USA

USGS Publications Warehouse

Docherty, Douglas E.; Franson, J. Christian; Brannian, Roger E.; Long, Renee R.; Radi, Craig A.; Krueger, David; Johnson, Robert F.

2012-01-01

In 1999, the U.S. Geological Survey (USGS) National Wildlife Health Center, Madison, Wisconsin, conducted a diagnostic investigation into a water bird mortality event involving intoxication with avian botulism type C and infection with avian chlamydiosis at the Benton Lake National Wildlife Refuge in Montana, USA. Of 24 carcasses necropsied, 11 had lesions consistent with avian chlamydiosis, including two that tested positive for infectious Chlamydophila psittaci, and 12 were positive for avian botulism type C. One bird tested positive for both avian botulism type C and C. psittaci. Of 61 apparently healthy water birds sampled and released, 13 had serologic evidence of C. psittaci infection and 7 were, at the time of capture, shedding infectious C. psittaci via the cloacal or oropharyngeal route. Since more routinely diagnosed disease conditions may mask avian chlamydiosis, these findings support the need for a comprehensive diagnostic investigation when determining the cause of a wildlife mortality event.

Analytical considerations for mass spectrometry profiling in serum biomarker discovery.

PubMed

Whiteley, Gordon R; Colantonio, Simona; Sacconi, Andrea; Saul, Richard G

2009-03-01

The potential of using mass spectrometry profiling as a diagnostic tool has been demonstrated for a wide variety of diseases. Various cancers and cancer-related diseases have been the focus of much of this work because of both the paucity of good diagnostic markers and the knowledge that early diagnosis is the most powerful weapon in treating cancer. The implementation of mass spectrometry as a routine diagnostic tool has proved to be difficult, however, primarily because of the stringent controls that are required for the method to be reproducible. The method is evolving as a powerful guide to the discovery of biomarkers that could, in turn, be used either individually or in an array or panel of tests for early disease detection. Using proteomic patterns to guide biomarker discovery and the possibility of deployment in the clinical laboratory environment on current instrumentation or in a hybrid technology has the possibility of being the early diagnosis tool that is needed.

Application of loop-mediated isothermal amplification (LAMP) assays for the detection of bovine herpesvirus 1.

PubMed

Socha, W; Rola, J; Urban-Chmiel, R; Żmudziński, J F

2017-09-26

Bovine herpesvirus-1 (BoHV-1), a causative agent of Infectious Bovine Rhinotracheitis (IBR), is responsible for high economic losses in cattle farming industry. The use of testing methods that allow early detection of BoHV-1-infected animals is a key element of each program of IBR eradication. The aim of the study was to design and evaluate two variants of LAMP isothermal tests with SYBR Green fluorescence probes, specific to the genes encoding gD and gE glycoproteins of BoHV-1. LAMP gE BoHV-1 assay was able to distinguish between gE- and gE+ strains of the virus. Both LAMP gD and gE assays were specific to BoHV-1 and did not react with other related to BoHV-1 alphaherpesviruses. Sensitivity of LAMP gD was 2x104 copies of the viral genome whereas for LAMP gE it was 2x105. Diagnostic sensitivity calculated for LAMP gD was 64.7% whereas for LAMP gE it was 80%. Diagnostic specificity for LAMP gD and LAMP gE was 78.9% and 89.3%, respectively. LAMP assay can be a rapid and simple method of diagnosis of acute BoHV-1 infections and discrimination of gE- strains. However, relatively low diagnostic sensitivity of the method can limit its use in routine diagnostics.

Feline focus: Diagnostic testing for feline thyroid disease: hyperthyroidism.

PubMed

Peterson, Mark E

2013-08-01

In older cats presenting with clinical features of hyperthyroidism, confirming the diagnosis of thyroid disease is usually straightforward. However, the potential for false-negative and false-positive results exists with all thyroid function tests, especially when used for routine screening of large numbers of asymptomatic cats. Therefore, all thyroid function test results must be interpreted in light of the cat's history, clinical signs, and other laboratory findings. If a high serum thyroxine (T4) value is found in a cat that lacks clinical signs of hyperthyroidism, or if hyperthyroidism is suspected in a cat with normal total T4 concentrations, repeating the total T4 analysis, determining the free T4 concentration, or performing thyroid scintigraphy may be needed to confirm the diagnosis.

Diagnosis of Brucellosis in Livestock and Wildlife

PubMed Central

Godfroid, Jacques; Nielsen, Klaus; Saegerman, Claude

2010-01-01

Aim To describe and discuss the merits of various direct and indirect methods applied in vitro (mainly on blood or milk) or in vivo (allergic test) for the diagnosis of brucellosis in animals. Methods The recent literature on brucellosis diagnostic tests was reviewed. These diagnostic tests are applied with different goals, such as national screening, confirmatory diagnosis, certification, and international trade. The validation of such diagnostic tests is still an issue, particularly in wildlife. The choice of the testing strategy depends on the prevailing brucellosis epidemiological situation and the goal of testing. Results Measuring the kinetics of antibody production after Brucella spp. infection is essential for analyzing serological results correctly and may help to predict abortion. Indirect ELISAs help to discriminate 1) between false positive serological reactions and true brucellosis and 2) between vaccination and infection. Biotyping of Brucella spp. provides valuable epidemiological information that allows tracing an infection back to the sources in instances where several biotypes of a given Brucella species are circulating. Polymerase chain reaction and new molecular methods are likely to be used as routine typing and fingerprinting methods in the coming years. Conclusion The diagnosis of brucellosis in livestock and wildlife is complex and serological results need to be carefully analyzed. The B. abortus S19 and B. melitensis Rev. 1 vaccines are the cornerstones of control programs in cattle and small ruminants, respectively. There is no vaccine available for pigs or for wildlife. In the absence of a human brucellosis vaccine, prevention of human brucellosis depends on the control of the disease in animals. PMID:20718082

Kericho CLinic-based ART Diagnostic Evaluation (CLADE): design, accrual, and baseline characteristics of a randomized controlled trial conducted in predominately rural, district-level, HIV clinics of Kenya.

PubMed

Sawe, Fredrick K; Obiero, Eunice; Yegon, Peter; Langat, Rither C; Aoko, Appolonia; Tarus, Jemutai; Kiptoo, Ignatius; Langat, Raphael K; Maswai, Jonah; Bii, Margaret; Khamadi, Samoel; Shikuku, Kibet P; Close, Nicole; Sinei, Samuel; Shaffer, Douglas N

2015-01-01

Prospective clinical trial data regarding routine HIV-1 viral load (VL) monitoring of antiretroviral therapy (ART) in non-research clinics of Sub-Saharan Africa are needed for policy makers. CLinic-based ART Diagnostic Evaluation (CLADE) is a randomized, controlled trial (RCT) evaluating feasibility, superiority, and cost-effectiveness of routine VL vs. standard of care (clinical and immunological) monitoring in adults initiating dual nucleoside reverse transcriptase inhibitor (NRTI)+non-NRTI ART. Participants were randomized (1:1) at 7 predominately rural, non-research, district-level clinics of western Kenya. Descriptive statistics present accrual patterns and baseline cohort characteristics. Over 15 months, 820 adults enrolled at 7 sites with 86-152 enrolled per site. Monthly site enrollment ranged from 2-92 participants. Full (100%) informed consent compliance was independently documented. Half (49.9%) had HIV diagnosed through voluntary counseling and testing. Study arms were similar: mostly females (57.6%) aged 37.6 (SD = 9.0) years with low CD4 (166 [SD = 106]) cells/m3). Notable proportions had WHO Stage III or IV disease (28.7%), BMI <18.5 kg/m2 (23.1%), and a history of tuberculosis (5.6%) or were receiving tuberculosis treatment (8.2%) at ART initiation. In the routine VL arm, 407/409 (99.5%) received baseline VL (234,577 SD = 151,055 copies/ml). All participants received lamivudine; 49.8% started zidovudine followed by 38.4% stavudine and 11.8% tenofovir; and, 64.4% received nevirapine as nNRTI (35.6% efavirenz). A RCT can be enrolled successfully in rural, non-research, resource limited, district-level clinics in western Kenya. Many adults presenting for ART have advanced HIV/AIDS, emphasizing the importance of universal HIV testing and linkage-to-care campaigns. ClinicalTrials.gov NCT01791556.

Clinical application of high throughput molecular screening techniques for pharmacogenomics

PubMed Central

Wiita, Arun P; Schrijver, Iris

2011-01-01

Genetic analysis is one of the fastest-growing areas of clinical diagnostics. Fortunately, as our knowledge of clinically relevant genetic variants rapidly expands, so does our ability to detect these variants in patient samples. Increasing demand for genetic information may necessitate the use of high throughput diagnostic methods as part of clinically validated testing. Here we provide a general overview of our current and near-future abilities to perform large-scale genetic testing in the clinical laboratory. First we review in detail molecular methods used for high throughput mutation detection, including techniques able to monitor thousands of genetic variants for a single patient or to genotype a single genetic variant for thousands of patients simultaneously. These methods are analyzed in the context of pharmacogenomic testing in the clinical laboratories, with a focus on tests that are currently validated as well as those that hold strong promise for widespread clinical application in the near future. We further discuss the unique economic and clinical challenges posed by pharmacogenomic markers. Our ability to detect genetic variants frequently outstrips our ability to accurately interpret them in a clinical context, carrying implications both for test development and introduction into patient management algorithms. These complexities must be taken into account prior to the introduction of any pharmacogenomic biomarker into routine clinical testing. PMID:23226057

Thoracoabdominal Computed Tomography in Trauma Patients: A Cost-Consequences Analysis

PubMed Central

van Vugt, Raoul; Kool, Digna R.; Brink, Monique; Dekker, Helena M.; Deunk, Jaap; Edwards, Michael J.

2014-01-01

Background: CT is increasingly used during the initial evaluation of blunt trauma patients. In this era of increasing cost-awareness, the pros and cons of CT have to be assessed. Objectives: This study was performed to evaluate cost-consequences of different diagnostic algorithms that use thoracoabdominal CT in primary evaluation of adult patients with high-energy blunt trauma. Materials and Methods: We compared three different algorithms in which CT was applied as an immediate diagnostic tool (rush CT), a diagnostic tool after limited conventional work-up (routine CT), and a selective tool (selective CT). Probabilities of detecting and missing clinically relevant injuries were retrospectively derived. We collected data on radiation exposure and performed a micro-cost analysis on a reference case-based approach. Results: Both rush and routine CT detected all thoracoabdominal injuries in 99.1% of the patients during primary evaluation (n = 1040). Selective CT missed one or more diagnoses in 11% of the patients in which a change of treatment was necessary in 4.8%. Rush CT algorithm costed € 2676 (US$ 3660) per patient with a mean radiation dose of 26.40 mSv per patient. Routine CT costed € 2815 (US$ 3850) and resulted in the same radiation exposure. Selective CT resulted in less radiation dose (23.23 mSv) and costed € 2771 (US$ 3790). Conclusions: Rush CT seems to result in the least costs and is comparable in terms of radiation dose exposure and diagnostic certainty with routine CT after a limited conventional work-up. However, selective CT results in less radiation dose exposure but a slightly higher cost and less certainty. PMID:25337521

Diagnostic accuracy of a standardized scheme for identification of Streptococcus uberis in quarter milk samples: A comparison between conventional bacteriological examination, modified Rambach agar medium culturing, and 16S rRNA gene sequencing.

PubMed

Wald, Regina; Baumgartner, Martina; Urbantke, Verena; Stessl, Beatrix; Wittek, Thomas

2017-02-01

Bacteriological examination of milk samples is a prerequisite for pathogen-specific therapy and aids in limiting antimicrobial resistance. The aims of this study were to establish a standardized scheme for reliable Streptococcus uberis identification in routine diagnosis and to evaluate the accuracy of conventional tests and growing patterns of Strep. uberis on a selective medium (modified Rambach agar medium, MRAM) using 16S rRNA gene sequencing analysis as a reference method. We obtained isolates of presumptive Strep. uberis (n = 336) from quarter milk samples of dairy cows with intramammary infections and classified the isolates into 2 clusters using biochemical characterization. In cluster 1 (n = 280), cocci grew as non-hemolytic colonies, hydrolyzing esculin, carrying no Lancefield antigen (A/B/C/D/G) or Christie Atkins Munch-Petersen factor, and their growth was inhibited on an Enterococcus agar. Production of β-d-galactosidase on MRAM was shown by 257 of the cluster 1 isolates (91.79%), and 16S rRNA gene sequencing verified 271 (96.79%) of the isolates to be Strep. uberis. In 264 isolates (94.29%), MRAM agreed with the sequencing results. In cluster 2 (n = 56), isolates showed different characteristics: 37 (66.07%) were β-d-galactosidase-positive, and based on 16S sequencing results, 36 (64.29%) were identified correctly as Strep. uberis using biochemical methods. Identification success in this group differed significantly between routine diagnosis and MRAM application: MRAM agreed with sequencing results in 47 isolates (83.93%). To identify Strep. uberis and differentiate it from other lactic acid bacteria in routine diagnosis, we suggest using catalase reaction, hemolysis, esculin hydrolysis, and growth on enterococci agar. Isolates that show a typical biochemical profile can be identified satisfactorily with these tests. For Strep. uberis isolates with divergent patterns, application of MRAM as a follow-up test increased the diagnostic accuracy to 94.64%. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Implementation of Amplicon Parallel Sequencing Leads to Improvement of Diagnosis and Therapy of Lung Cancer Patients.

PubMed

König, Katharina; Peifer, Martin; Fassunke, Jana; Ihle, Michaela A; Künstlinger, Helen; Heydt, Carina; Stamm, Katrin; Ueckeroth, Frank; Vollbrecht, Claudia; Bos, Marc; Gardizi, Masyar; Scheffler, Matthias; Nogova, Lucia; Leenders, Frauke; Albus, Kerstin; Meder, Lydia; Becker, Kerstin; Florin, Alexandra; Rommerscheidt-Fuss, Ursula; Altmüller, Janine; Kloth, Michael; Nürnberg, Peter; Henkel, Thomas; Bikár, Sven-Ernö; Sos, Martin L; Geese, William J; Strauss, Lewis; Ko, Yon-Dschun; Gerigk, Ulrich; Odenthal, Margarete; Zander, Thomas; Wolf, Jürgen; Merkelbach-Bruse, Sabine; Buettner, Reinhard; Heukamp, Lukas C

2015-07-01

The Network Genomic Medicine Lung Cancer was set up to rapidly translate scientific advances into early clinical trials of targeted therapies in lung cancer performing molecular analyses of more than 3500 patients annually. Because sequential analysis of the relevant driver mutations on fixated samples is challenging in terms of workload, tissue availability, and cost, we established multiplex parallel sequencing in routine diagnostics. The aim was to analyze all therapeutically relevant mutations in lung cancer samples in a high-throughput fashion while significantly reducing turnaround time and amount of input DNA compared with conventional dideoxy sequencing of single polymerase chain reaction amplicons. In this study, we demonstrate the feasibility of a 102 amplicon multiplex polymerase chain reaction followed by sequencing on an Illumina sequencer on formalin-fixed paraffin-embedded tissue in routine diagnostics. Analysis of a validation cohort of 180 samples showed this approach to require significantly less input material and to be more reliable, robust, and cost-effective than conventional dideoxy sequencing. Subsequently, 2657 lung cancer patients were analyzed. We observed that comprehensive biomarker testing provided novel information in addition to histological diagnosis and clinical staging. In 2657 consecutively analyzed lung cancer samples, we identified driver mutations at the expected prevalence. Furthermore we found potentially targetable DDR2 mutations at a frequency of 3% in both adenocarcinomas and squamous cell carcinomas. Overall, our data demonstrate the utility of systematic sequencing analysis in a clinical routine setting and highlight the dramatic impact of such an approach on the availability of therapeutic strategies for the targeted treatment of individual cancer patients.

Fast virtual functional assessment of intermediate coronary lesions using routine angiographic data and blood flow simulation in humans: comparison with pressure wire - fractional flow reserve.

PubMed

Papafaklis, Michail I; Muramatsu, Takashi; Ishibashi, Yuki; Lakkas, Lampros S; Nakatani, Shimpei; Bourantas, Christos V; Ligthart, Jurgen; Onuma, Yoshinobu; Echavarria-Pinto, Mauro; Tsirka, Georgia; Kotsia, Anna; Nikas, Dimitrios N; Mogabgab, Owen; van Geuns, Robert-Jan; Naka, Katerina K; Fotiadis, Dimitrios I; Brilakis, Emmanouil S; Garcia-Garcia, Héctor M; Escaned, Javier; Zijlstra, Felix; Michalis, Lampros K; Serruys, Patrick W

2014-09-01

To develop a simplified approach of virtual functional assessment of coronary stenosis from routine angiographic data and test it against fractional flow reserve using a pressure wire (wire-FFR). Three-dimensional quantitative coronary angiography (3D-QCA) was performed in 139 vessels (120 patients) with intermediate lesions assessed by wire-FFR (reference standard: ≤0.80). The 3D-QCA models were processed with computational fluid dynamics (CFD) to calculate the lesion-specific pressure gradient (ΔP) and construct the ΔP-flow curve, from which the virtual functional assessment index (vFAI) was derived. The discriminatory power of vFAI for ischaemia- producing lesions was high (area under the receiver operator characteristic curve [AUC]: 92% [95% CI: 86-96%]). Diagnostic accuracy, sensitivity and specificity for the optimal vFAI cut-point (≤0.82) were 88%, 90% and 86%, respectively. Virtual-FAI demonstrated superior discrimination against 3D-QCA-derived % area stenosis (AUC: 78% [95% CI: 70- 84%]; p<0.0001 compared to vFAI). There was a close correlation (r=0.78, p<0.0001) and agreement of vFAI compared to wire-FFR (mean difference: -0.0039±0.085, p=0.59). We developed a fast and simple CFD-powered virtual haemodynamic assessment model using only routine angiography and without requiring any invasive physiology measurements/hyperaemia induction. Virtual-FAI showed a high diagnostic performance and incremental value to QCA for predicting wire-FFR; this "less invasive" approach could have important implications for patient management and cost.

Comparison of Saramis 4.12 and IVD 3.0 Vitek MS Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry for Identification of Mycobacteria from Solid and Liquid Culture Media

PubMed Central

Leyer, Caroline; Gregorowicz, Guillaume; Mougari, Faiza; Raskine, Laurent; Cambau, Emmanuelle

2017-01-01

ABSTRACT During the last decade, many investigators have studied matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) for identification of mycobacteria. Diverse and contradictory results indicated that optimal level for routine testing has not been reached yet. This work aimed to assess Vitek MS through two distinct versions, Saramis v4.12 RUO and the IVD v3.0, under conditions close to routine laboratory practice. Overall, 111 mycobacterial isolates were subjected to protein extraction and same spectra were matched against both databases. The IVD v3.0 database proved to be superior to Saramis v4.12 and its identification rates remarkably increased, from 67% to 94% for isolates grown on Middlebrook 7H10 solid medium and from 62% to 91% for isolates grown on mycobacterial growth indicator tube (MGIT) liquid medium. With this new version, IVD v3.0, MALDI-TOF MS might be integrated into routine clinical diagnostics, although molecular techniques remain mandatory in some cases. PMID:28424252

[Blood volume for biochemistry determinations--laboratory needs and everyday practice].

PubMed

Sztefko, Krystyna; Mamica, Katarzyna; Bugajska, Jolanta; Maziarz, Barbara; Tomasik, Przemysław

2014-01-01

Blood loss due to diagnostic phlebotomy jest a very serious problem, especially for newborn, infants and critically ill patients on intensive care units. Although single blood loss can be easily tolerated in adults, in small babies and in patients who are frequently monitored based on laboratory tests iatrogenic anaemia can occur. To evaluate the blood volume drawn for routine biochemistry tests in relation to patient age and the number of parameters requested. Blood volume drawn for routine biochemistry measurements from patients hospitalized in University Children's Hospital (N = 2980, children age from one day to 18 years) and in University Hospital (N = 859, adults, aged > 1.8 years) in Cracow has been analyzed. Blood volume was calculated based on regular tube diameter and blood heights in the tube. In case of microvettes the blood volume was 0.2 ml. Statistical analysis has been performed by using PRISM 5.0. The statistical significance was set at p < 0.05. The mean values of blood volume were 3.02 +/- 0.92 ml and 4.12 +/- 0.68 ml in children and adults, respectively. Analyzing blood volume drawn in children using both microvettes and regular tubes, significant correlation between blood volume and patient age (p < 0.001) as well the number of requested parameters (p < 0.001). The latest relationship was true only for up to five parameters. However, analyzing the blood volume drawn into only into regular tubes blood volume was not related to patients age and number of laboratory tests requested. The proportion of microvettes used for blood collection was highest for newborns and infants, and in all cases where only one to three laboratory tests were requested. 1. All educational programs for nurses and doctors should include the information about current laboratory automation and methods miniaturization; 2) The amount of blood volume needed by laboratory for the requested number of tests should always be taken into account when diagnostic phlebotomy is necessary.

Diagnostic value of serum Golgi protein 73 for HBV-related primary hepatic carcinoma

PubMed Central

Gao, Guosheng; Dong, Feibo; Xu, Xiaozhen; Hu, Airong; Hu, Yaoren

2015-01-01

Background: Alpha-fetoprotein (AFP) levels are routinely used for diagnosis and monitoring of hepatic diseases, but it has a limited value. Golgi protein 73 (GP73) has been suggested as a new marker for hepatic diseases. Objective: To explore the clinical value of serum GP73 in different diseases associated with hepatitis B virus (HBV) infection. Method: Between January 2010 and August 2014, serum samples from 88 patients with chronic hepatitis B (CHB), 78 patients with HBV-related liver cirrhosis (LC), and 194 patients with HBV-related primary hepatic cancer (PHC) were collected. Serum samples from 30 healthy volunteers were used as controls. ELISA and microparticle enzyme immunoassay were used to measure serum GP73 and AFP levels. Receiver operating characteristic (ROC) curves were used to analyze the diagnostic value of serum GP73 and AFP for PHC. Results: For the diagnosis of PHC, GP73 showed a sensitivity of 65.5% and specificity of 66.3%, while AFP levels showed sensitivity of 64.4% and specificity of 76.5%. Serial testing (both tests are positive) could increase the specificity (sensitivity of 45.9% and specificity of 85.5%) while parallel testing (any single positive test result) could increase the sensitivity (sensitivity of 84.0% and specificity of 57.2%). Serum GP73 and AFP levels were significantly different between Child-Pugh grades (P<0.001 for GP73 and P=0.044 for AFP). Significant differences in serum GP73 and AFP were found between TNM stages (all P<0.001). Conclusion: Serum GP73 had limited diagnostic value for HBV-related PHC. The combined use of serum GP73 and AFP levels improved the diagnostic efficacy. PMID:26617863

Preanalytical management: serum vacuum tubes validation for routine clinical chemistry.

PubMed

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Picheth, Geraldo; Guidi, Gian Cesare

2012-01-01

The validation process is essential in accredited clinical laboratories. Aim of this study was to validate five kinds of serum vacuum tubes for routine clinical chemistry laboratory testing. Blood specimens from 100 volunteers in five different serum vacuum tubes (Tube I: VACUETTE, Tube II: LABOR IMPORT, Tube III: S-Monovette, Tube IV: SST and Tube V: SST II) were collected by a single, expert phlebotomist. The routine clinical chemistry tests were analyzed on cobas 6000 module. The significance of the differences between samples was assessed by paired Student's t-test after checking for normality. The level of statistical significance was set at P < 0.005. Finally, the biases from Tube I, Tube II, Tube III, Tube IV and Tube V were compared with the current desirable quality specifications for bias (B), derived from biological variation. Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according him/her technical or economical reasons, in order to perform the following laboratory tests: glucose, total cholesterol, high density lipoprotein-cholesterol, triglycerides, total protein, albumin, blood urea nitrogen, uric acid, alkaline phosphatise, aspartate aminotransferase, gamma-glutamyltransferase, lactate dehydrogenase, creatine kinase, total bilirubin, direct bilirubin, calcium, iron, sodium and potassium. On the contrary special attention will be required if the laboratory already performs creatinine, amylase, phosphate and magnesium determinations and the quality laboratory manager intend to change the serum tubes. We suggest that laboratory management should both standardize the procedures and frequently evaluate the quality of in vitro diagnostic devices.

Preanalytical management: serum vacuum tubes validation for routine clinical chemistry

PubMed Central

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Picheth, Geraldo; Guidi, Gian Cesare

2012-01-01

Introduction The validation process is essential in accredited clinical laboratories. Aim of this study was to validate five kinds of serum vacuum tubes for routine clinical chemistry laboratory testing. Materials and methods: Blood specimens from 100 volunteers in five diff erent serum vacuum tubes (Tube I: VACUETTE®, Tube II: LABOR IMPORT®, Tube III: S-Monovette®, Tube IV: SST® and Tube V: SST II®) were collected by a single, expert phlebotomist. The routine clinical chemistry tests were analyzed on cobas® 6000 module. The significance of the diff erences between samples was assessed by paired Student’s t-test after checking for normality. The level of statistical significance was set at P < 0.005. Finally, the biases from Tube I, Tube II, Tube III, Tube IV and Tube V were compared with the current desirable quality specifications for bias (B), derived from biological variation. Results and conclusions: Basically, our validation will permit the laboratory or hospital managers to select the brand’s vacuum tubes validated according him/her technical or economical reasons, in order to perform the following laboratory tests: glucose, total cholesterol, high density lipoprotein-cholesterol, triglycerides, total protein, albumin, blood urea nitrogen, uric acid, alkaline phosphatise, aspartate aminotransferase, gamma-glutamyltransferase, lactate dehydrogenase, creatine kinase, total bilirubin, direct bilirubin, calcium, iron, sodium and potassium. On the contrary special attention will be required if the laboratory already performs creatinine, amylase, phosphate and magnesium determinations and the quality laboratory manager intend to change the serum tubes. We suggest that laboratory management should both standardize the procedures and frequently evaluate the quality of in vitro diagnostic devices. PMID:22838184

Malaria rapid diagnostic tests in endemic settings.

PubMed

Maltha, J; Gillet, P; Jacobs, J

2013-05-01

Malaria rapid diagnostic tests (RDTs) are instrument-free tests that provide results within 20 min and can be used by community health workers. RDTs detect antigens produced by the Plasmodium parasite such as Plasmodium falciparum histidine-rich protein-2 (PfHPR2) and Plasmodium lactate dehydrogenase (pLDH). The accuracy of RDTs for the diagnosis of uncomplicated P. falciparum infection is equal or superior to routine microscopy (but inferior to expert microscopy). Sensitivity for Plasmodium vivax is 75-100%; for Plasmodium ovale and Plasmodium malariae, diagnostic performance is poor. Design limitations of RDTs include poor sensitivity at low parasite densities, susceptibility to the prozone effect (PfHRP2-detecting RDTs), false-negative results due to PfHRP2 deficiency in the case of pfhrp2 gene deletions (PfHRP2-detecting RDTs), cross-reactions between Plasmodium antigens and detection antibodies, false-positive results by other infections and susceptibility to heat and humidity. End-user's errors relate to safety, procedure (delayed reading, incorrect sample and buffer volumes) and interpretation (not recognizing invalid test results, disregarding faint test lines). Withholding antimalarial treatment in the case of negative RDT results tends to be infrequent and tendencies towards over-prescription of antibiotics have been noted. Numerous shortcomings in RDT kits' labelling, instructions for use (correctness and readability) and contents have been observed. The World Health Organization and partners actively address quality assurance of RDTs by comparative testing of RDTs, inspections of manufacturing sites, lot testing and training tools but no formal external quality assessment programme of end-user performance exists. Elimination of malaria requires RDTs with lower detection limits, for which nucleic acid amplification tests are under development. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

Performance of a lateral flow immunochromatography test for the rapid diagnosis of active tuberculosis in a large multicentre study in areas with different clinical settings and tuberculosis exposure levels.

PubMed

Manga, Selene; Perales, Rocio; Reaño, Maria; D'Ambrosio, Lia; Migliori, Giovanni Battista; Amicosante, Massimo

2016-11-01

Tuberculosis (TB) continues to cause an outsized burden of morbidity and mortality worldwide, still missing efficient and largely accessible diagnostic tools determining an appropriate control of the disease. Serological tests have the potentially to impact TB diagnosis, in particular in extreme clinical settings. The diagnostic performances of the TB-XT HEMA EXPRESS (HEMA-EXPRESS) immunochromatographic rapid test for active TB diagnosis, based on use of multiple Mycobacterium tuberculosis (MTB) specific antigens, have been evaluated in a large study multicentre TB case-finding study, in populations with different exposure level to TB. A total of 1,386 subjects were enrolled in the six participating centres in Peru: 290 active-TB and 1,096 unaffected subjects. The TB prevalence (overall 20.5%) varied between 4.0% and 41.1% in the different study groups. Overall, the HEMA-EXPRESS test had 30.6% sensitivity (range 3.9-77.9%) and 84.6% specificity (range 51.6-97.3%). A significant inverse correlation between test accuracy (overall 73.5%, range 40.4-96.4%) and TB prevalence in the various study populations was observed (Pearson's r=-0.7985; P=0.05). HEMA-EXPRESS, is rapid and relatively inexpensive test suitable for routine use in TB diagnosis. In low TB prevalence conditions, test performance appears in line with WHO Target Product Profile for TB diagnostics. Performances appear suboptimal in high TB prevalence settings. Appropriate set-up in operative clinical settings has to be considered for novel serological tests for TB diagnosis, particularly for formats suitable for point-of-care use.

Hematology of the Domestic Ferret (Mustela putorius furo).

PubMed

Smith, Stephen A; Zimmerman, Kurt; Moore, David M

2015-09-01

Pet ferrets are presented to veterinary clinics for routine care and treatment of clinical diseases and female reproductive problems. In addition to obtaining clinical history, additional diagnostic testing may be required, including hematological assessments. This article describes common blood collection methods, including venipuncture sites, volume of blood that can be safely collected, and handling of the blood. Hematological parameters for normal ferrets are provided along with a description of the morphology of ferret leukocytes to assist in performing a differential count. Copyright © 2015 Elsevier Inc. All rights reserved.

Early effects of whole body irradiation on cholinesterase activity in guinea-pigs' blood, with special regard to radiation sickness

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lundin, J; Clemedson, C -J; Nelson, A

1957-07-01

Male guinea-pigs suffered a loss of cholinesterase activity in plasma amounting to about 30% during the first two days after whole-body roentgen irradiation with 400 r. No changes in the activity of acetylcholinesterase in erythrocytes to be ascribed to the irradiation could be demonstrated during the first two days. A routine method for determination of the cholinesterase activities has been tested but is found less suitable as a diagnostic tool for the early recognition of the effects of irradiation.

Cost-benefit analysis of introducing next-generation sequencing (metagenomic) pathogen testing in the setting of pyrexia of unknown origin.

PubMed

Chai, Jia Hui; Lee, Chun Kiat; Lee, Hong Kai; Wong, Nicholas; Teo, Kahwee; Tan, Chuen Seng; Thokala, Praveen; Tang, Julian Wei-Tze; Tambyah, Paul Anantharajah; Oh, Vernon Min Sen; Loh, Tze Ping; Yoong, Joanne

2018-01-01

Pyrexia of unknown origin (PUO) is defined as a temperature of >38.3°C that lasts for >3 weeks, where no cause can be found despite appropriate investigation. Existing protocols for the work-up of PUO can be extensive and costly, motivating the application of recent advances in molecular diagnostics to pathogen testing. There have been many reports describing various analytical methods and performance of metagenomic pathogen testing in clinical samples but the economics of it has been less well studied. This study pragmatically evaluates the feasibility of introducing metagenomic testing in this setting by assessing the relative cost of clinically-relevant strategies employing this investigative tool under various cost and performance scenarios using Singapore as a demonstration case, and assessing the price and performance benchmarks, which would need to be achieved for metagenomic testing to be potentially considered financially viable relative to the current diagnostic standard. This study has some important limitations: we examined only impact of introducing the metagenomic test to the overall diagnostic cost and excluded costs associated with hospitalization and makes assumptions about the performance of the routine diagnostic tests, limiting the cost of metagenomic test, and the lack of further work-up after positive pathogen detection by the metagenomic test. However, these assumptions were necessary to keep the model within reasonable limits. In spite of these, the simplified presentation lends itself to the illustration of the key insights of our paper. In general, we find the use of metagenomic testing as second-line investigation is effectively dominated, and that use of metagenomic testing at first-line would typically require higher rates of detection or lower cost than currently available in order to be justifiable purely as a cost-saving measure. We conclude that current conditions do not warrant a widespread rush to deploy metagenomic testing to resolve any and all uncertainty, but rather as a front-line technology that should be used in specific contexts, as a supplement to rather than a replacement for careful clinical judgement.

Parasite detection in patients with post kala-azar dermal leishmaniasis in India: a comparison between molecular and immunological methods

PubMed Central

Salotra, P; Sreenivas, G; Beena, K R; Mukherjee, A; Ramesh, V

2003-01-01

Aims: To evaluate the sensitivity and specificity of serological, immunohistochemical, and molecular methods in the diagnosis of post kala-azar dermal leishmaniasis (PKDL). Methods: Twenty five patients with confirmed PKDL and 25 controls were included in the study. G2D10, a monoclonal antibody against Leishmania, was used for the immunohistochemical (IHC) staining of lesion sections to visualise anti-Leishmania donovani antibodies. The diagnostic usefulness of IHC was compared with enzyme linked immunosorbent assay (ELISA) with a recombinant (rk39) antigen, and a species specific polymerase chain reaction (PCR) assay, amplifying a kinetoplast minicircle DNA sequence. Results: IHC detected 22 of 25 PKDL cases, giving a sensitivity of 88%. The diagnostic sensitivity of both the ELISA and PCR tests was higher (96%). All of the 25 controls examined were negative in PCR, indicating 100% specificity of the test, whereas ELISA showed 96% specificity. Conclusions: IHC with G2D10 significantly enhances the sensitivity of detection of PKDL over routine haematoxylin and eosin staining. ELISA with a recombinant antigen is an economical and practical assay. PCR is the most sensitive and specific diagnostic method for PKDL. The tests described would facilitate the recognition of patients with PKDL, enabling timely treatment, which would contribute greatly to the control of kala-azar. PMID:14600129

Routine Ultrasound and Limited Computed Tomography for the Diagnosis of Acute Appendicitis

PubMed Central

Wiersma, Fraukje; Bakker, Rutger F. R.; Merkus, Jos W. S.; Breslau, Paul J.; Hamming, Jaap F.

2010-01-01

Background Acute appendicitis continues to be a challenging diagnosis. Preoperative radiological imaging using ultrasound (US) or computed tomography (CT) has gained popularity as it may offer a more accurate diagnosis than classic clinical evaluation. The optimal implementation of these diagnostic modalities has yet to be established. The aim of the present study was to investigate a diagnostic pathway that uses routine US, limited CT, and clinical re-evaluation for patients with acute appendicitis. Methods A prospective analysis was performed of all patients presenting with acute abdominal pain at the emergency department from June 2005 until July 2006 using a structured diagnosis and management flowchart. Daily practice was mimicked, while ensuring a valid assessment of clinical and radiological diagnostic accuracies and the effect they had on patient management. Results A total of 802 patients were included in this analysis. Additional radiological imaging was performed in 96.3% of patients with suspected appendicitis (n = 164). Use of CT was kept to a minimum (17.9%), with a US:CT ratio of approximately 6:1. Positive and negative predictive values for the clinical diagnosis of appendicitis were 63 and 98%, respectively; for US 94 and 97%, respectively; and for CT 100 and 100%, respectively. The negative appendicitis rate was 3.3%, the perforation rate was 23.5%, and the missed perforated appendicitis rate was 3.4%. No (diagnostic) laparoscopies were performed. Conclusions A diagnostic pathway using routine US, limited CT, and clinical re-evaluation for patients with acute abdominal pain can provide excellent results for the diagnosis and treatment of appendicitis. PMID:20582544

SU-E-P-10: Establishment of Local Diagnostic Reference Levels of Routine Exam in Computed Tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yeh, M; Wang, Y; Weng, H

Introduction National diagnostic reference levels (NDRLs) can be used as a reference dose of radiological examination can provide radiation dose as the basis of patient dose optimization. Local diagnostic reference levels (LDRLs) by periodically view and check doses, more efficiency to improve the way of examination. Therefore, the important first step is establishing a diagnostic reference level. Computed Tomography in Taiwan had been built up the radiation dose limit value,in addition, many studies report shows that CT scan contributed most of the radiation dose in different medical. Therefore, this study was mainly to let everyone understand DRL’s international status. Formore » computed tomography in our hospital to establish diagnostic reference levels. Methods and Materials: There are two clinical CT scanners (a Toshiba Aquilion and a Siemens Sensation) were performed in this study. For CT examinations the basic recommended dosimetric quantity is the Computed Tomography Dose Index (CTDI). Each exam each different body part, we collect 10 patients at least. Carried out the routine examinations, and all exposure parameters have been collected and the corresponding CTDIv and DLP values have been determined. Results: The majority of patients (75%) were between 60–70 Kg of body weight. There are 25 examinations in this study. Table 1 shows the LDRL of each CT routine examination. Conclusions: Therefore, this study would like to let everyone know DRL’s international status, but also establishment of computed tomography of the local reference levels for our hospital, and providing radiation reference, as a basis for optimizing patient dose.« less

Measuring the Level of Agreement Between Cloacal Gram's Stains and Bacterial Cultures in Hispaniolan Amazon Parrots ( Amazona ventralis ).

PubMed

Evans, Erika E; Mitchell, Mark A; Whittington, Julia K; Roy, Alma; Tully, Thomas N

2014-12-01

Cloacal or fecal Gram's stains and bacterial cultures are routinely performed during avian physical examinations to assess the microbial flora of the gastrointestinal tract. Although cloacal or fecal Gram's stains and bacterial cultures are considered routine diagnostic procedures, the level of agreement between the individual tests has not been determined. To investigate the level of agreement between results from Gram's stain and bacterial culture when used to assess cloacal or fecal samples from psittacine birds, samples were taken from 21 clinically healthy Hispaniolan Amazon parrots ( Amazona ventralis ) and tested by Gram's stain cytology and bacterial culture. Most bacteria (97.2%) identified by Gram's stain were gram positive. However, gram-negative organisms were identified in 7 of 21 (33.3%; 95% confidence interval: 13.3%-53.3%) birds. Escherichia coli was the only gram-negative organism identified on culture. Agreement between results of Gram's stain and culture was fair (weighted κ = 0.27). The results of this study suggest that Gram's stains and bacterial culture may need to be performed with a parallel testing strategy to limit the likelihood of misclassifying the microbial flora of psittacine patients.

Non-invasive assessment of liver fibrosis

PubMed Central

Papastergiou, Vasilios; Tsochatzis, Emmanuel; Burroughs, Andrew K.

2012-01-01

The presence and degree of hepatic fibrosis is crucial in order to make therapeutic decisions and predict clinical outcomes. Currently, the place of liver biopsy as the standard of reference for assessing liver fibrosis has been challenged by the increasing awareness of a number of drawbacks related to its use (invasiveness, sampling error, inter-/intraobserver variability). In parallel with this, noninvasive assessment of liver fibrosis has experienced explosive growth in recent years and a wide spectrum of noninvasive methods ranging from serum assays to imaging techniques have been developed. Some are validated methods, such as the Fibrotest/ Fibrosure and transient elastography in Europe, and are gaining a growing role in routine clinical practice, especially in chronic hepatitis C. Large-scale validation is awaited in the setting of other chronic liver diseases. However, noninvasive tests used to detect significant fibrosis and cirrhosis, the two major clinical endpoints, are not yet at a level of performance suitable for routine diagnostic tests, and there is still no perfect surrogate or method able to completely replace an optimal liver biopsy. This article aims to review current noninvasive tests for the assessment of liver fibrosis and the perspectives for their rational use in clinical practice. PMID:24714123

Differentiation of the serological response to Yersinia enterocolitica and Brucella abortus in cattle

PubMed Central

Corbel, M. J.; Cullen, G. A.

1970-01-01

The serological responses of cattle to inoculation with Brucella abortus and Yersinia enterocolitica type IX were compared. Complete cross-reactions were found in serum agglutination, antiglobulin, complement fixation and Rose Bengal plate tests. The cross-reaction between Br. abortus and Y. enterocolitica IX was confirmed by immunodiffusion tests. Although antibodies specific for each organism could also be detected by immunodiffusion tests with high titre rabbit or bovine sera, these tests were insufficiently sensitive for routine diagnostic use. A quantitative Rose Bengal plate test, using Rose Bengal stained Br. abortus and Y. enterocolitica IX, was developed which enabled the antibody responses to the two organisms to be differentiated. The specificity of this test was confirmed by cross-absorption experiments and its sensitivity was sufficient to permit evaluation of all bovine sera giving positive reactions to the serum agglutination test. ImagesFig. 1Fig. 2 PMID:4992575

Modern psychophysical tests to assess olfactory function.

PubMed

Eibenstein, A; Fioretti, A B; Lena, C; Rosati, N; Amabile, G; Fusetti, M

2005-07-01

The sense of smell significantly contributes to quality of life. In recent years much progress has been made in understanding the biochemistry, physiology and pathology of the human olfactory system. Olfactory disorders may arise not only from upper airway phlogosis but also from neurodegenerative disease. Hyposmia may precede motor signs in Parkinson's disease and cognitive deficit in Alzheimer's disease. These findings suggest the complementary role of olfactory tests in the diagnosis and management of neurodegenerative diseases. In this report we present a review of modern olfactory tests and their clinical applications. Although rarely employed in routine clinical practice, the olfactory test evaluates the ability of odour identification and is a useful diagnostic tool for olfaction evaluation. Olfactory screening tests are also available. In this work we strongly recommend the importance of an ENT evaluation before the test administration and dissuade from a self-administration of an olfactory test.

Diagnostic methods for platelet bacteria screening: current status and developments.

PubMed

Störmer, Melanie; Vollmer, Tanja

2014-02-01

Bacterial contamination of blood components and the prevention of transfusion-associated bacterial infection still remains a major challenge in transfusion medicine. Over the past few decades, a significant reduction in the transmission of viral infections has been achieved due to the introduction of mandatory virus screening. Platelet concentrates (PCs) represent one of the highest risks for bacterial infection. This is due to the required storage conditions for PCs in gas-permeable containers at room temperature with constant agitation, which support bacterial proliferation from low contamination levels to high titers. In contrast to virus screening, since 1997 in Germany bacterial testing of PCs is only performed as a routine quality control or, since 2008, to prolong the shelf life to 5 days. In general, bacterial screening of PCs by cultivation methods is implemented by the various blood services. Although these culturing systems will remain the gold standard, the significance of rapid methods for screening for bacterial contamination has increased over the last few years. These new methods provide powerful tools for increasing the bacterial safety of blood components. This article summarizes the course of policies and provisions introduced to increase bacterial safety of blood components in Germany. Furthermore, we give an overview of the different diagnostic methods for bacterial screening of PCs and their current applicability in routine screening processes.

Automation of the linear array HPV genotyping test and its application for routine typing of human papillomaviruses in cervical specimens of women without cytological abnormalities in Switzerland.

PubMed

Dobec, Marinko; Bannwart, Fridolin; Kaeppeli, Franz; Cassinotti, Pascal

2009-05-01

There is a need for reliable, automated high throughput HPV detection and genotyping methods for pre- and post-prophylactic vaccine intervention analyses. To optimize the linear array (LA) HPV genotyping test (Roche Diagnostics, Rotkreuz) in regard to possible automation steps for the routine laboratory diagnosis of HPV infections and to analyze the HPV genotype distribution in cervical specimens of women without cytological abnormalities in Switzerland. 680 cervical cell specimens with normal cytology, obtained from women undergoing routine cervical screening by liquid-based Pap smear, were analyzed by the LA HPV genotyping test for HPV-DNA. The automation of the LA HPV genotyping test resulted in a total hands-on time reduction of 255 min (from 480 to 225 min; 53%). Any of 37 HPV genotypes were detected in 117 (17.2%) and high-risk (HR) HPV in 55 (8.1%) of 680 women with normal cytology. The highest prevalence of any HPV (28.1%) and HR-HPV (15.1%) was observed in age-group 21-30 and showed a continuous decrease in older age-groups. The most common HR-HPV genotypes were HPV-16 (12%), HPV-31 (9.4%), HPV-52 (6%), HPV-51 (5.1%), HPV-45 (4.3%), HPV-58 (4.3%) and HPV-59 (4.3%). The optimization and automation of the LA HPV genotyping test makes it suited for high throughput HPV detection and typing. The epidemiological data provides information about distribution of HPV genotypes in women without cytological abnormalities in Switzerland and may be important for determining the future impact of vaccines and potential changes in the country's epidemiological HPV profile.

Low levels of neurocognitive impairment detected in screening HIV-infected men who have sex with men: The MSM Neurocog Study.

PubMed

Barber, T J; Bansi, L; Pozniak, A; Asboe, D; Nelson, M; Moyle, G; Davies, N; Margetts, A; Ratcliffe, D; Catalan, J; Boffito, M; Gazzard, B

2017-06-01

This study aimed to determine the prevalence of HIV neurocognitive impairment in HIV-infected men who have sex with men aged 18-50 years, using a simple battery of screening tests in routine clinical appointments. Those with suspected abnormalities were referred on for further assessment. The cohort was also followed up over time to look at evolving changes. HIV-infected participants were recruited at three clinical sites in London during from routine clinical visits. They could be clinician or self-referred and did not need to be symptomatic. They completed questionnaires on anxiety, depression, and memory. They were then screened using the Brief Neurocognitive Screen (BNCS) and International HIV Dementia Scale (IHDS). Two hundred and five HIV-infected subjects were recruited. Of these, 59 patients were excluded as having a mood disorder and two patients were excluded due to insufficient data, leaving 144 patients for analysis. One hundred and twenty-four (86.1%) had a normal composite z score (within 1 SD of mean) calculated for their scores on the three component tests of the BNCS. Twenty (13.9%) had an abnormal z score, of which seven (35%) were symptomatic and 13 (65%) asymptomatic. Current employment and previous educational level were significantly associated with BNCS scores. Of those referred onwards for diagnostic testing, only one participant was found to have impairment likely related to HIV infection. We were able to easily screen for mood disorders and cognitive impairment in routine clinical practice. We identified a high level of depression and anxiety in our cohort. Using simple screening tests in clinic and an onward referral process for further testing, we were not able to identify neurocognitive impairment in this cohort at levels consistent with published data.

Mimics and chameleons in motor neurone disease

PubMed Central

Turner, Martin R; Talbot, Kevin

2013-01-01

The progression of motor neurone disease (MND) is currently irreversible, and the grave implications of diagnosis naturally fuels concern among neurologists over missing a potential mimic disorder. There is no diagnostic test for MND but in reality there are few plausible mimics in routine clinical practice. In the presence of a progressive pure motor disorder, signs such as florid fasciculations, bilateral tongue wasting, the ‘split hand’, head drop, emotionality, and cognitive or behavioural impairment carry high positive predictive value. MND is clinically heterogeneous, however, with some important chameleon-like presentations and considerable variation in clinical course. Lack of confidence about the scope of such variation, or an approach to diagnosis emphasising investigations over clinical common sense, has the potential to exacerbate diagnostic delay in MND and impede timely planning of the care which is essential to maximising quality of life. PMID:23616620

Genetic antimicrobial susceptibility testing in Gram-negative sepsis - impact on time to results in a routine laboratory.

PubMed

Kommedal, Øyvind; Aasen, Johanne Lind; Lindemann, Paul Christoffer

2016-07-01

Diagnostic testing of positive blood cultures is among the most critical tasks performed by clinical microbiology laboratories, and the total analysis time from sampling to results should be kept as short as possible. By providing identification of pelleted bacteria directly from positive blood-cultures, MALDI-TOF MS opens for relatively low-complex species-adjusted genetic susceptibility testing from the same bacterial pellet. In our lab routine, we prospectively evaluated a rapid in-house real-time PCR targeting the most common aminoglycoside and cephalosporin resistance genes in Escherichia coli and Klebsiella pneumoniae and measured time to preliminary susceptibility reporting for 138 samples. The results were compared to direct phenotypic susceptibility testing with interpretation after 6 h and overnight incubation respectively. Results from the genetic susceptibility testing were available for 69.5% (96/138) of the positive blood cultures within 24 h after sample collection. No phenotypic susceptibility results were available at this time. Compared to overnight direct susceptibility testing, the average time from sample collection to preliminary susceptibility reporting was reduced with 43%, from 45 h and 5 min to 25 h and 44 min, providing an earlier adjustment of antimicrobial therapy for 12 patients. Minor logistic adjustments have the potential to save yet another 4 h. © 2016 APMIS. Published by John Wiley & Sons Ltd.

Predictive value of anaemia for tuberculosis in HIV-infected patients in sub-Saharan Africa: an indication for routine microbiological investigation using new rapid assays

PubMed Central

Kerkhoff, Andrew D.; Wood, Robin; Vogt, Monica; Lawn, Stephen D.

2014-01-01

Background The relationship between anaemia and undiagnosed tuberculosis (TB) in patients living with HIV in sub-Saharan Africa is incompletely defined. We assessed the prevalence of TB among those with HIV-related anaemia and evaluated new means of rapid TB diagnosis. Methodology Blood haemoglobin levels were measured in unselected antiretroviral treatment (ART)-naïve patients in Cape Town, South Africa, and anaemia was classified according to WHO criteria. All patients were screened for TB by testing paired sputum samples using liquid culture (reference standard), fluorescence microscopy and Xpert MTB/RIF. Urine samples were tested for lipoarabinomannan (LAM) using the Determine TB-LAM diagnostic assay. Results Of 602 adults screened, 485 had complete results. Normal haemoglobin levels were found in 44.5% (n=216) of patients and mild, moderate or severe anaemia were present in 24.9% (n=121), 25.4% (n=123) and 5.2% (n=25) of patients, respectively. Culture-confirmed pulmonary TB was diagnosed in 8.8% (19/216) of those without anaemia compared to 16.5% (20/121), 26.0% (32/123) and 40.0% (10/25) with mild, moderate or severe anaemia, respectively (p<0.001). Anaemia was a strong independent predictor of TB. The sensitivities of diagnostic assays were much higher among those with moderate/severe anaemia compared to those with no/mild anaemia using sputum microscopy (42.9% vs 15.4%); urine LAM (54.8% vs 0%); sputum microscopy plus urine LAM (71.4% vs 15.4%) and sputum Xpert (73.8% vs 41.0%) (P<0.01 for all). Conclusions A very high prevalence of undiagnosed TB was found in patients with moderate or severe anaemia. Such patients should be prioritized for routine microbiological investigation using rapid diagnostic assays. PMID:24346639

Liquid Biopsy in Non-Small Cell Lung Cancer

PubMed Central

Molina-Vila, Miguel A.; Mayo-de-las-Casas, Clara; Giménez-Capitán, Ana; Jordana-Ariza, Núria; Garzón, Mónica; Balada, Ariadna; Villatoro, Sergi; Teixidó, Cristina; García-Peláez, Beatriz; Aguado, Cristina; Catalán, María José; Campos, Raquel; Pérez-Rosado, Ana; Bertran-Alamillo, Jordi; Martínez-Bueno, Alejandro; Gil, María-de-los-Llanos; González-Cao, María; González, Xavier; Morales-Espinosa, Daniela; Viteri, Santiago; Karachaliou, Niki; Rosell, Rafael

2016-01-01

Liquid biopsy analyses are already incorporated in the routine clinical practice in many hospitals and oncology departments worldwide, improving the selection of treatments and monitoring of lung cancer patients. Although they have not yet reached its full potential, liquid biopsy-based tests will soon be as widespread as “standard” biopsies and imaging techniques, offering invaluable diagnostic, prognostic, and predictive information. This review summarizes the techniques available for the isolation and analysis of circulating free DNA and RNA, exosomes, tumor-educated platelets, and circulating tumor cells from the blood of cancer patients, presents the methodological challenges associated with each of these materials, and discusses the clinical applications of liquid biopsy testing in lung cancer. PMID:28066769

Evaluation of an inhouse rapid ELISA test for detection of giardia in domestic sheep (Ovis aries).

PubMed

Wilson, Jolaine M; Hankenson, F Claire

2010-11-01

Sheep (Ovis aries) are increasingly used at our institution as models of human disease. Within the research environment, routine husbandry and handling of sheep has potential for transmission of zoonotic agents, including Giardia. The prevalence of Giardia in sheep may approach 68%. Classic diagnostic testing involves microscopic examination for fecal cysts or trophozoites; however, limitations of microscopy include time, labor, and potential false-negative results due to intermittent shedding. We wished to determine whether a commercial rapid ELISA used for Giardia detection in dogs and cats could be used in sheep. Fecal samples collected from sheep (n = 93) were tested with a combination of 6 methods: reference laboratory fecal flotation, reference laboratory ELISA, inhouse fecal flotation, and commercially available tests (enzyme immunoassay, direct fluorescence antibody assay, and rapid ELISA). Prevalence of Giardia infection in facility sheep was 11.8% (11 of 93 animals). Of the 11 samples considered positive, 3 were confirmed by multiple testing methods, and 5 were positive by microscopy alone. Inhouse fecal flotation for 8 samples was positive on only 1 of 2 consecutive testing days. The rapid ELISA test exhibited 0% sensitivity for sheep giardiasis. Overall, the examined methods had low sensitivities and low positive predictive values. Despite limitations, microscopic analysis of repeat fecal samples remained the most accurate diagnostic method for ovine giardiasis among the methods tested.

Muscle Oxygen Saturation Improves Diagnostic Association Between Initial Vital Signs and Major Hemorrhage: A Prospective Observational Study.

PubMed

Reisner, Andrew T; Edla, Shwetha; Liu, Jianbo; Rubin, John T; Thorsen, Jill E; Kittell, Erin; Smith, Jason B; Yeh, Daniel D; Reifman, Jaques

2016-03-01

During initial assessment of trauma patients, vital signs do not identify all patients with life-threatening hemorrhage. We hypothesized that a novel vital sign, muscle oxygen saturation (SmO2 ), could provide independent diagnostic information beyond routine vital signs for identification of hemorrhaging patients who require packed red blood cell (RBC) transfusion. This was an observational study of adult trauma patients treated at a Level I trauma center. Study staff placed the CareGuide 1100 tissue oximeter (Reflectance Medical Inc., Westborough, MA), and we analyzed average values of SmO2 , systolic blood pressure (sBP), pulse pressure (PP), and heart rate (HR) during 10 minutes of early emergency department evaluation. We excluded subjects without a full set of vital signs during the observation interval. The study outcome was hemorrhagic injury and RBC transfusion ≥ 3 units in 24 hours (24-hr RBC ≥ 3). To test the hypothesis that SmO2 added independent information beyond routine vital signs, we developed one logistic regression model with HR, sBP, and PP and one with SmO2 in addition to HR, sBP, and PP and compared their areas under receiver operating characteristic curves (ROC AUCs) using DeLong's test. We enrolled 487 subjects; 23 received 24-hr RBC ≥ 3. Compared to the model without SmO2 , the regression model with SmO2 had a significantly increased ROC AUC for the prediction of ≥ 3 units of 24-hr RBC volume, 0.85 (95% confidence interval [CI], 0.75-0.91) versus 0.77 (95% CI, 0.66-0.86; p < 0.05 per DeLong's test). Results were similar for ROC AUCs predicting patients (n = 11) receiving 24-hr RBC ≥ 9. SmO2 significantly improved the diagnostic association between initial vital signs and hemorrhagic injury with blood transfusion. This parameter may enhance the early identification of patients who require blood products for life-threatening hemorrhage. © 2016 The Authors. Academic Emergency Medicine published by Wiley Periodicals, Inc. on behalf of Society for Academic Emergency Medicine.

Prevalence of posttraumatic growth hormone deficiency is highly dependent on the diagnostic set-up: results from The Danish National Study on Posttraumatic Hypopituitarism.

PubMed

Klose, Marianne; Stochholm, Kirstine; Janukonyté, Jourgita; Lehman Christensen, Louise; Frystyk, Jan; Andersen, Marianne; Laurberg, Peter; Christiansen, Jens Sandahl; Feldt-Rasmussen, Ulla

2014-01-01

Recent international guidelines suggest pituitary screening in patients with moderate and severe traumatic brain injury (TBI). Predominantly isolated GH deficiency (GHD) was reported in the literature, raising the question of potential methodological bias. Our objective was to assess the prevalence of GHD in patients admitted in 2008 with TBI, with concurrent assessment of methodological bias. We conducted a nationwide population-based cohort study at tertiary referral university hospitals. Participants were Danish patients with a head trauma diagnosis from the Danish Board of Health diagnostic code registry; 439 patients and 124 healthy controls underwent dynamic assessment of GH secretion 2.5 years (median) after TBI. We evaluated the prevalence of GHD given use of 1) local versus guideline cutoffs, 2) insulin tolerance test (ITT), pyridostigmine (PD)-GHRH or GHRH-arginine (arg) test, 3) single versus repeated testing, and 4) GH assessment by assays with different isoform specificities. The prevalence of GHD was lower by local than by guideline cutoffs (12% vs 19% [PD-GHRH/GHRH-arg, P<.001]; 4.5% vs 5% [ITT, P=.9]), and by ITT than by PD-GHRH/GHRH-arg (P=.006 [local cutoffs]; P<.001 [guideline cutoffs]). Only 1% of patients had GHD according to 2 tests. GH assessment by the Immulite or iSYS assay caused no significant diagnostic differences. The study confirmed a high risk of bias in the management of pituitary testing of patients with TBI and stresses the importance of a proper control group and stringent GH testing including confirmatory testing in cohorts with low a priori likelihood of GHD such as in TBI. Our results question the evidence for newly introduced recommendations for routine pituitary assessment in TBI.

Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry in Clinical Microbiology: What Are the Current Issues?

PubMed Central

Welker, Martin; Pincus, David; Charrier, Jean-Philippe; Girard, Victoria

2017-01-01

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has revolutionized the identification of microbial species in clinical microbiology laboratories. MALDI-TOF-MS has swiftly become the new gold-standard method owing to its key advantages of simplicity and robustness. However, as with all new methods, adoption of the MALDI-TOF MS approach is still not widespread. Optimal sample preparation has not yet been achieved for several applications, and there are continuing discussions on the need for improved database quality and the inclusion of additional microbial species. New applications such as in the field of antimicrobial susceptibility testing have been proposed but not yet translated to the level of ease and reproducibility that one should expect in routine diagnostic systems. Finally, during routine identification testing, unexpected results are regularly obtained, and the best methods for transmitting these results into clinical care are still evolving. We here discuss the success of MALDI-TOF MS in clinical microbiology and highlight fields of application that are still amenable to improvement. PMID:28840984

Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry in Clinical Microbiology: What Are the Current Issues?

PubMed

van Belkum, Alex; Welker, Martin; Pincus, David; Charrier, Jean Philippe; Girard, Victoria

2017-11-01

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has revolutionized the identification of microbial species in clinical microbiology laboratories. MALDI-TOF-MS has swiftly become the new gold-standard method owing to its key advantages of simplicity and robustness. However, as with all new methods, adoption of the MALDI-TOF MS approach is still not widespread. Optimal sample preparation has not yet been achieved for several applications, and there are continuing discussions on the need for improved database quality and the inclusion of additional microbial species. New applications such as in the field of antimicrobial susceptibility testing have been proposed but not yet translated to the level of ease and reproducibility that one should expect in routine diagnostic systems. Finally, during routine identification testing, unexpected results are regularly obtained, and the best methods for transmitting these results into clinical care are still evolving. We here discuss the success of MALDI-TOF MS in clinical microbiology and highlight fields of application that are still amenable to improvement. © The Korean Society for Laboratory Medicine.

Clinical applicability and cost of a 46-gene panel for genomic analysis of solid tumours: Retrospective validation and prospective audit in the UK National Health Service.

PubMed

Hamblin, Angela; Wordsworth, Sarah; Fermont, Jilles M; Page, Suzanne; Kaur, Kulvinder; Camps, Carme; Kaisaki, Pamela; Gupta, Avinash; Talbot, Denis; Middleton, Mark; Henderson, Shirley; Cutts, Anthony; Vavoulis, Dimitrios V; Housby, Nick; Tomlinson, Ian; Taylor, Jenny C; Schuh, Anna

2017-02-01

Single gene tests to predict whether cancers respond to specific targeted therapies are performed increasingly often. Advances in sequencing technology, collectively referred to as next generation sequencing (NGS), mean the entire cancer genome or parts of it can now be sequenced at speed with increased depth and sensitivity. However, translation of NGS into routine cancer care has been slow. Healthcare stakeholders are unclear about the clinical utility of NGS and are concerned it could be an expensive addition to cancer diagnostics, rather than an affordable alternative to single gene testing. We validated a 46-gene hotspot cancer panel assay allowing multiple gene testing from small diagnostic biopsies. From 1 January 2013 to 31 December 2013, solid tumour samples (including non-small-cell lung carcinoma [NSCLC], colorectal carcinoma, and melanoma) were sequenced in the context of the UK National Health Service from 351 consecutively submitted prospective cases for which treating clinicians thought the patient had potential to benefit from more extensive genetic analysis. Following histological assessment, tumour-rich regions of formalin-fixed paraffin-embedded (FFPE) sections underwent macrodissection, DNA extraction, NGS, and analysis using a pipeline centred on Torrent Suite software. With a median turnaround time of seven working days, an integrated clinical report was produced indicating the variants detected, including those with potential diagnostic, prognostic, therapeutic, or clinical trial entry implications. Accompanying phenotypic data were collected, and a detailed cost analysis of the panel compared with single gene testing was undertaken to assess affordability for routine patient care. Panel sequencing was successful for 97% (342/351) of tumour samples in the prospective cohort and showed 100% concordance with known mutations (detected using cobas assays). At least one mutation was identified in 87% (296/342) of tumours. A locally actionable mutation (i.e., available targeted treatment or clinical trial) was identified in 122/351 patients (35%). Forty patients received targeted treatment, in 22/40 (55%) cases solely due to use of the panel. Examination of published data on the potential efficacy of targeted therapies showed theoretically actionable mutations (i.e., mutations for which targeted treatment was potentially appropriate) in 66% (71/107) and 39% (41/105) of melanoma and NSCLC patients, respectively. At a cost of £339 (US$449) per patient, the panel was less expensive locally than performing more than two or three single gene tests. Study limitations include the use of FFPE samples, which do not always provide high-quality DNA, and the use of "real world" data: submission of cases for sequencing did not always follow clinical guidelines, meaning that when mutations were detected, patients were not always eligible for targeted treatments on clinical grounds. This study demonstrates that more extensive tumour sequencing can identify mutations that could improve clinical decision-making in routine cancer care, potentially improving patient outcomes, at an affordable level for healthcare providers.

Diagnostic trends in Clostridium difficile detection in Finnish microbiology laboratories.

PubMed

Könönen, Eija; Rasinperä, Marja; Virolainen, Anni; Mentula, Silja; Lyytikäinen, Outi

2009-12-01

Due to increased interest directed to Clostridium difficile-associated infections, a questionnaire survey of laboratory diagnostics of toxin-producing C. difficile was conducted in Finland in June 2006. Different aspects pertaining to C. difficile diagnosis, such as requests and criteria used for testing, methods used for its detection, yearly changes in diagnostics since 1996, and the total number of investigations positive for C. difficile in 2005, were asked in the questionnaire, which was sent to 32 clinical microbiology laboratories, including all hospital-affiliated and the relevant private clinical microbiology laboratories in Finland. The situation was updated by phone and email correspondence in September 2008. In June 2006, 28 (88%) laboratories responded to the questionnaire survey; 24 of them reported routinely testing requested stool specimens for C. difficile. Main laboratory methods included toxin detection (21/24; 88%) and/or anaerobic culture (19/24; 79%). In June 2006, 18 (86%) of the 21 laboratories detecting toxins directly from feces, from the isolate, or both used methods for both toxin A (TcdA) and B (TcdB), whereas only one laboratory did so in 1996. By September 2008, all of the 23 laboratories performing diagnostics for C. difficile used methods for both TcdA and TcdB. In 2006, the number of specimens processed per 100,000 population varied remarkably between different hospital districts. In conclusion, culturing C. difficile is common and there has been a favorable shift in toxin detection practice in Finnish clinical microbiology laboratories. However, the variability in diagnostic activity reported in 2006 creates a challenge for national monitoring of the epidemiology of C. difficile and related diseases.

High test positivity and low positive predictive value for colorectal cancer of continued faecal occult blood test screening after negative colonoscopy.

PubMed

Brown, Jeremy P; Wooldrage, Kate; Wright, Suzanne; Nickerson, Claire; Cross, Amanda J; Atkin, Wendy S

2018-06-01

Objectives The English Bowel Cancer Screening Programme offers biennial guaiac faecal occult blood test (gFOBT) screening to 60-74-year-olds. Participants with positive results are referred for follow-up, but many do not have significant findings. If they remain age eligible, these individuals are reinvited for gFOBT screening. We evaluated the performance of repeat screening in this group. Methods We analysed data on programme participants reinvited to gFOBT screening after either previous negative gFOBT ( n = 327,542), or positive gFOBT followed by a diagnostic investigation negative for colorectal cancer (CRC) or adenomas requiring surveillance ( n = 42,280). Outcomes calculated were uptake, test positivity, yield of CRC, and positive predictive value (PPV) of gFOBT for CRC. Results For participants with a previous negative gFOBT, uptake in the subsequent screening round was 87.5%, positivity was 1.3%, yield of CRC was 0.112% of those adequately screened, and the PPV of gFOBT for CRC was 9.1%. After a positive gFOBT and a negative diagnostic investigation, uptake in the repeat screening round was 82.6%, positivity was 11.3%, CRC yield was 0.172% of participants adequately screened, and the PPV of gFOBT for CRC was 1.7%. Conclusion With high positivity and low PPV for CRC, the suitability of routine repeat gFOBT screening in two years among individuals with a previous positive test and a negative diagnostic examination needs to be carefully considered.

A 30-Min Nucleic Acid Amplification Point-of-Care Test for Genital Chlamydia trachomatis Infection in Women: A Prospective, Multi-center Study of Diagnostic Accuracy.

PubMed

Harding-Esch, E M; Cousins, E C; Chow, S-L C; Phillips, L T; Hall, C L; Cooper, N; Fuller, S S; Nori, A V; Patel, R; Thomas-William, S; Whitlock, G; Edwards, S J E; Green, M; Clarkson, J; Arlett, B; Dunbar, J K; Lowndes, C M; Sadiq, S T

2018-02-01

Rapid Point-Of-Care Tests for Chlamydia trachomatis (CT) may reduce onward transmission and reproductive sexual health (RSH) sequelae by reducing turnaround times between diagnosis and treatment. The io® single module system (Atlas Genetics Ltd.) runs clinical samples through a nucleic acid amplification test (NAAT)-based CT cartridge, delivering results in 30min. Prospective diagnostic accuracy study of the io® CT-assay in four UK Genito-Urinary Medicine (GUM)/RSH clinics on additional-to-routine self-collected vulvovaginal swabs. Samples were tested "fresh" within 10days of collection, or "frozen" at -80°C for later testing. Participant characteristics were collected to assess risk factors associated with CT infection. CT prevalence was 7.2% (51/709) overall. Sensitivity, specificity, positive and negative predictive values of the io® CT assay were, respectively, 96.1% (95% Confidence Interval (CI): 86.5-99.5), 97.7% (95%CI: 96.3-98.7), 76.6% (95%CI: 64.3-86.2) and 99.7% (95%CI: 98.9-100). The only risk factor associated with CT infection was being a sexual contact of an individual with CT. The io® CT-assay is a 30-min, fully automated, high-performing NAAT currently CE-marked for CT diagnosis in women, making it a highly promising diagnostic to enable specific treatment, initiation of partner notification and appropriately intensive health promotion at the point of care. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Bringing the state into the clinic? Incorporating the rapid diagnostic test for malaria into routine practice in Tanzanian primary healthcare facilities

PubMed Central

Hutchinson, Eleanor; Reyburn, Hugh; Hamlyn, Eleanor; Long, Katie; Meta, Judith; Mbakilwa, Hilda; Chandler, Clare

2017-01-01

ABSTRACT The roles that rapid, point-of-care tests will play in healthcare in low-income settings are likely to expand over the coming years. Yet, very little is known about how they are incorporated into practice, and what it means to use and rely upon them. This paper focuses on the rapid diagnostic test for malaria (mRDT), examining its introduction into low-level public health facilities in Tanzania within an intervention to improve the targeting of costly malaria medication. We interviewed 26 health workers to explore how a participatory training programme, mobile phone messages, posters and leaflets shaped the use and interpretation of the test. Drawing on notions of biopolitics, this paper examines how technologies of the self and mechanisms of surveillance bolstered the role mRDT in clinical decision-making. It shows how the significance of the test interacted with local knowledge, the availability of other medication, and local understandings of good clinical practice. Our findings suggest that in a context in which care is reduced to the provision of medicines, strict adherence to mRDT results may be underpinned by increasing the use of other pharmaceuticals or may leave health workers with patients for whom they are unable to provide care. PMID:26457440

Bringing the state into the clinic? Incorporating the rapid diagnostic test for malaria into routine practice in Tanzanian primary healthcare facilities.

PubMed

Hutchinson, Eleanor; Reyburn, Hugh; Hamlyn, Eleanor; Long, Katie; Meta, Judith; Mbakilwa, Hilda; Chandler, Clare

2017-09-01

The roles that rapid, point-of-care tests will play in healthcare in low-income settings are likely to expand over the coming years. Yet, very little is known about how they are incorporated into practice, and what it means to use and rely upon them. This paper focuses on the rapid diagnostic test for malaria (mRDT), examining its introduction into low-level public health facilities in Tanzania within an intervention to improve the targeting of costly malaria medication. We interviewed 26 health workers to explore how a participatory training programme, mobile phone messages, posters and leaflets shaped the use and interpretation of the test. Drawing on notions of biopolitics, this paper examines how technologies of the self and mechanisms of surveillance bolstered the role mRDT in clinical decision-making. It shows how the significance of the test interacted with local knowledge, the availability of other medication, and local understandings of good clinical practice. Our findings suggest that in a context in which care is reduced to the provision of medicines, strict adherence to mRDT results may be underpinned by increasing the use of other pharmaceuticals or may leave health workers with patients for whom they are unable to provide care.

Basic principles of test-negative design in evaluating influenza vaccine effectiveness.

PubMed

Fukushima, Wakaba; Hirota, Yoshio

2017-08-24

Based on the unique characteristics of influenza, the concept of "monitoring" influenza vaccine effectiveness (VE) across the seasons using the same observational study design has been developed. In recent years, there has been a growing number of influenza VE reports using the test-negative design, which can minimize both misclassification of diseases and confounding by health care-seeking behavior. Although the test-negative designs offer considerable advantages, there are some concerns that widespread use of the test-negative design without knowledge of the basic principles of epidemiology could produce invalid findings. In this article, we briefly review the basic concepts of the test-negative design with respect to classic study design such as cohort studies or case-control studies. We also mention selection bias, which may be of concern in some countries where rapid diagnostic testing is frequently used in routine clinical practices, as in Japan. Copyright © 2017. Published by Elsevier Ltd.

Navigating highly homologous genes in a molecular diagnostic setting: a resource for clinical next-generation sequencing.

PubMed

Mandelker, Diana; Schmidt, Ryan J; Ankala, Arunkanth; McDonald Gibson, Kristin; Bowser, Mark; Sharma, Himanshu; Duffy, Elizabeth; Hegde, Madhuri; Santani, Avni; Lebo, Matthew; Funke, Birgit

2016-12-01

Next-generation sequencing (NGS) is now routinely used to interrogate large sets of genes in a diagnostic setting. Regions of high sequence homology continue to be a major challenge for short-read technologies and can lead to false-positive and false-negative diagnostic errors. At the scale of whole-exome sequencing (WES), laboratories may be limited in their knowledge of genes and regions that pose technical hurdles due to high homology. We have created an exome-wide resource that catalogs highly homologous regions that is tailored toward diagnostic applications. This resource was developed using a mappability-based approach tailored to current Sanger and NGS protocols. Gene-level and exon-level lists delineate regions that are difficult or impossible to analyze via standard NGS. These regions are ranked by degree of affectedness, annotated for medical relevance, and classified by the type of homology (within-gene, different functional gene, known pseudogene, uncharacterized noncoding region). Additionally, we provide a list of exons that cannot be analyzed by short-amplicon Sanger sequencing. This resource can help guide clinical test design, supplemental assay implementation, and results interpretation in the context of high homology.Genet Med 18 12, 1282-1289.

Should we be testing for urogenital Mycoplasma hominis, Ureaplasma parvum and U. urealyticum in men and women? - a Position Statement from the European STI Guidelines Editorial Board.

PubMed

Horner, P; Donders, G; Cusini, M; Gomberg, M; Jensen, J S; Unemo, M

2018-06-20

At present, we have no evidence that we are doing more good than harm detecting and subsequently treating Mycoplasma hominis, Ureaplasma parvum and Ureaplasma urealyticum colonisations/infections. Consequently, routine testing and treatment of asymptomatic or symptomatic men and women for M. hominis, U. urealyticum, and U. parvum is not recommended. Asymptomatic carriage of these bacteria is common and the majority of individuals do not develop disease. Although U. urealyticum has been associated with urethritis in men, it is probably not causal unless a high load is present (likely carriage in 40-80% of detected cases). The extensive testing, detection and subsequent antimicrobial treatment of these bacteria performed in some settings may result in selection of antimicrobial resistance, in these bacteria, "true" STI agents, as well as in the general microbiota, and substantial economic cost for society and individuals, particularly women. The commercialisation of many particularly multiplex PCR assays detecting traditional non-viral STIs together with M. hominis, U. parvum and/or U. urealyticum have worsened this situation. Thus, routine screening of asymptomatic men and women or routine testing of symptomatic individuals for M. hominis, U. urealyticum, and U. parvum is not recommended. If testing of men with symptomatic urethritis is undertaken, traditional STI urethritis agents such as Neisseria gonorrhoeae, Chlamydia trachomatis, M. genitalium and, in settings where relevant, Trichomonas vaginalis should be excluded prior to U. urealyticum testing and quantitative species-specific molecular diagnostic tests should be used. Only men with high U. urealyticum load should be considered for treatment, however, appropriate evidence for effective treatment regimens is lacking. In symptomatic women, bacterial vaginosis (BV) should always be tested for and treated if detected. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Towards a proposal for a universal diagnostic definition of protein-losing enteropathy in Fontan patients: a systematic review.

PubMed

Udink Ten Cate, Floris Ea; Hannes, Tobias; Germund, Ingo; Khalil, Markus; Huntgeburth, Michael; Apitz, Christian; Brockmeier, Konrad; Sreeram, Narayanswami

2016-07-15

A standardised diagnostic definition of protein-losing enteropathy (PLE) in Fontan patients serves both patient care and research. The present study determined whether a diagnostic definition of PLE was routinely used in published clinical Fontan studies, and to identify potentially relevant diagnostic criteria for composing a uniform PLE definition. A systematic review was conducted in adherence to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) recommendations. Published clinical Fontan studies that were written in English and included at least four patients with PLE were selected. PLE definitions were quantitatively analysed using a lateral thinking tool in which definitions were fractionated into constituent pieces of information (building blocks or diagnostic criteria). We identified 364 papers. In the final analysis, data from 62 published articles were extracted. A diagnostic definition of PLE was used in only 27/62 (43.5%) of selected studies, and definitions were very heterogeneous. We identified eight major diagnostic criteria. Hypoalbuminaemia (n=23 studies, 85.2%), clinical presentation (n=18, 66.7%), documentation of enteric protein loss (n=16, 59.3%) and exclusion of other causes of hypoproteinaemia (n=17, 63.0%), were the most frequently used diagnostic criteria. Most studies used three diagnostic variables (n=13/27, 48.1%). Cut-off values for laboratory parameters (serum albumin, protein or faecal α-1-antitrypsin) were frequently incorporated in the PLE definition (n=16, 59.3%). Establishment of a universally accepted PLE definition for routine use in clinical research and daily practice is required. The diagnostic criteria may help constitute a diagnostic PLE definition. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Photoacoustic spectroscopic differences between normal and malignant thyroid tissues

NASA Astrophysics Data System (ADS)

Li, Li; Xie, Wengming; Li, Hui

2012-12-01

The thyroid is one of the main endocrine glands of human body, which plays a crucial role in the body's metabolism. Thyroid cancer mortality ranks only second to ovarian cancer in endocrine cancer. Routine diagnostic methods of thyroid diseases in present clinic exist misdiagnosis and missed diagnosis to varying degrees. Those lead to miss the best period of cancer treatment--early. Photoacoustic spectroscopy technology is a new tool, which provides an effective and noninvasive way for biomedical materials research, being highly sensitive and without sample pretreatment. In this paper, we use photoacoustic spectroscopy technology (PAST) to detect the absorption spectrum between normal and malignant thyroid tissues. The result shows that the photoacoustic spectroscopy technology (PAST) could differentiate malignant thyroid tissue from normal thyroid tissue very well. This technique combined with routine diagnostic methods has the potential to increase the diagnostic accuracy in clinical thyroid cancer diagnosis.

Combination of culture, antigen and toxin detection, and cytotoxin neutralization assay for optimal Clostridium difficile diagnostic testing

PubMed Central

Alfa, Michelle J; Sepehri, Shadi

2013-01-01

BACKGROUND: There has been a growing interest in developing an appropriate laboratory diagnostic algorithm for Clostridium difficile, mainly as a result of increases in both the number and severity of cases of C difficile infection in the past decade. A C difficile diagnostic algorithm is necessary because diagnostic kits, mostly for the detection of toxins A and B or glutamate dehydrogenase (GDH) antigen, are not sufficient as stand-alone assays for optimal diagnosis of C difficile infection. In addition, conventional reference methods for C difficile detection (eg, toxigenic culture and cytotoxin neutralization [CTN] assays) are not routinely practiced in diagnostic laboratory settings. OBJECTIVE: To review the four-step algorithm used at Diagnostic Services of Manitoba sites for the laboratory diagnosis of toxigenic C difficile. RESULT: One year of retrospective C difficile data using the proposed algorithm was reported. Of 5695 stool samples tested, 9.1% (n=517) had toxigenic C difficile. Sixty per cent (310 of 517) of toxigenic C difficile stools were detected following the first two steps of the algorithm. CTN confirmation of GDH-positive, toxin A- and B-negative assays resulted in detection of an additional 37.7% (198 of 517) of toxigenic C difficile. Culture of the third specimen, from patients who had two previous negative specimens, detected an additional 2.32% (12 of 517) of toxigenic C difficile samples. DISCUSSION: Using GDH antigen as the screening and toxin A and B as confirmatory test for C difficile, 85% of specimens were reported negative or positive within 4 h. Without CTN confirmation for GDH antigen and toxin A and B discordant results, 37% (195 of 517) of toxigenic C difficile stools would have been missed. Following the algorithm, culture was needed for only 2.72% of all specimens submitted for C difficile testing. CONCLUSION: The overview of the data illustrated the significance of each stage of this four-step C difficile algorithm and emphasized the value of using CTN assay and culture as parts of an algorithm that ensures accurate diagnosis of toxigenic C difficile. PMID:24421808

Diagnostic accuracy of a two-item Drug Abuse Screening Test (DAST-2).

PubMed

Tiet, Quyen Q; Leyva, Yani E; Moos, Rudolf H; Smith, Brandy

2017-11-01

Drug use is prevalent and costly to society, but individuals with drug use disorders (DUDs) are under-diagnosed and under-treated, particularly in primary care (PC) settings. Drug screening instruments have been developed to identify patients with DUDs and facilitate treatment. The Drug Abuse Screening Test (DAST) is one of the most well-known drug screening instruments. However, similar to many such instruments, it is too long for routine use in busy PC settings. This study developed and validated a briefer and more practical DAST for busy PC settings. We recruited 1300 PC patients in two Department of Veterans Affairs (VA) clinics. Participants responded to a structured diagnostic interview. We randomly selected half of the sample to develop and the other half to validate the new instrument. We employed signal detection techniques to select the best DAST items to identify DUDs (based on the MINI) and negative consequences of drug use (measured by the Inventory of Drug Use Consequences). Performance indicators were calculated. The two-item DAST (DAST-2) was 97% sensitive and 91% specific for DUDs in the development sample and 95% sensitive and 89% specific in the validation sample. It was highly sensitive and specific for DUD and negative consequences of drug use in subgroups of patients, including gender, age, race/ethnicity, marital status, educational level, and posttraumatic stress disorder status. The DAST-2 is an appropriate drug screening instrument for routine use in PC settings in the VA and may be applicable in broader range of PC clinics. Published by Elsevier Ltd.

External quality assurance of HER2 fluorescence in situ hybridisation testing: results of a UK NEQAS pilot scheme.

PubMed

Bartlett, John M S; Ibrahim, Merdol; Jasani, Bharat; Morgan, John M; Ellis, Ian; Kay, Elaine; Magee, Hilary; Barnett, Sarah; Miller, Keith

2007-07-01

Trastuzumab provides clinical benefit for advanced and early breast cancer patients whose tumours over-express or have gene amplification of the HER2 oncogene. The UK National External Quality Assessment Scheme (NEQAS) for immunohistochemical testing was established to assess and improve the quality of HER2 immunohistochemical testing. However, until recently, no provision was available for HER2 fluorescence in situ hybridisation (FISH) testing. A pilot scheme was set up to review the performance of FISH testing in clinical diagnostic laboratories. FISH was performed in 6 reference and 31 participating laboratories using a cell line panel with known HER2 status. Using results from reference laboratories as a criterion for acceptable performance, 60% of all results returned by participants were appropriate and 78% either appropriate or acceptable. However, 22.4% of results returned were deemed inappropriate, including 13 cases (4.2%) where a misdiagnosis would have been made had these been clinical specimens. The results of three consecutive runs show that both reference laboratories and a proportion of routine clinical diagnostic (about 25%) centres can consistently achieve acceptable quality control of HER2 testing. Data from a significant proportion of participating laboratories show that further steps are required, including those taken via review of performance under schemes such as NEQAS, to improve quality of HER2 testing by FISH in the "real world".

Correlation or Limits of Agreement? Applying the Bland-Altman Approach to the Comparison of Cognitive Screening Instruments.

PubMed

Larner, A J

2016-01-01

Calculation of correlation coefficients is often undertaken as a way of comparing different cognitive screening instruments (CSIs). However, test scores may correlate but not agree, and high correlation may mask lack of agreement between scores. The aim of this study was to use the methodology of Bland and Altman to calculate limits of agreement between the scores of selected CSIs and contrast the findings with Pearson's product moment correlation coefficients between the test scores of the same instruments. Datasets from three pragmatic diagnostic accuracy studies which examined the Mini-Mental State Examination (MMSE) vs. the Montreal Cognitive Assessment (MoCA), the MMSE vs. the Mini-Addenbrooke's Cognitive Examination (M-ACE), and the M-ACE vs. the MoCA were analysed to calculate correlation coefficients and limits of agreement between test scores. Although test scores were highly correlated (all >0.8), calculated limits of agreement were broad (all >10 points), and in one case, MMSE vs. M-ACE, was >15 points. Correlation is not agreement. Highly correlated test scores may conceal broad limits of agreement, consistent with the different emphases of different tests with respect to the cognitive domains examined. Routine incorporation of limits of agreement into diagnostic accuracy studies which compare different tests merits consideration, to enable clinicians to judge whether or not their agreement is close. © 2016 S. Karger AG, Basel.

[Advances of Molecular Diagnostic Techniques Application in Clinical Diagnosis.

PubMed

Ying, Bin-Wu

2016-11-01

Over the past 20 years,clinical molecular diagnostic technology has made rapid development,and became the most promising field in clinical laboratory medicine.In particular,with the development of genomics,clinical molecular diagnostic methods will reveal the nature of clinical diseases in a deeper level,thus guiding the clinical diagnosis and treatments.Many molecular diagnostic projects have been routinely applied in clinical works.This paper reviews the advances on application of clinical diagnostic techniques in infectious disease,tumor and genetic disorders,including nucleic acid amplification,biochip,next-generation sequencing,and automation molecular system,and so on.

Diagnostic Hysteroscopy - A Retrospective Study of 1545 Cases

PubMed Central

STEFANESCU, Andreea; MARINESCU, Bogdan

2012-01-01

ABSTRACT Introduction: The development of hysteroscopy has provided a minimally invasive approach to common gynecologic problems, such as abnormal uterine bleeding. Diagnostic hysteroscopy is considered now "the gold standard" by the Association of Professors of Gynecology and Obstetrics (2002) in investigation of abnormal uterine bleeding (AUB) in order to rule out organic endouterine causes of AUB. Although the World Health Organization (WHO) recommends hysterosapingography (HSG) alone for management of infertile women many specialists use hysteroscopy as a first-line routine exam for infertility patients regardless of guidelines. Material and method: This paper is a retrospective study of 1545 diagnostic hysteroscopies performed in the "Prof. Dr. Panait Sirbu" Obstetrics and Gynecology Hospital between January 1, 2008 and June 30, 2011. The following parameters were studied: diagnostic hysteroscopy indications, type of anesthesia used, correlation between pre-and postoperative diagnoses. Outcomes: Of 1545 diagnostic hysteroscopies, 78% of cases were performed without anesthesia; of the total of 299 cases of primary infertility diagnostic hysteroscopy showed in 34% of cases tubal obstruction and endouterine pathology; of the total 396 cases of secondary infertility under investigation, diagnostic hysteroscopy showed in 40% of cases tubal obstruction and endouterine pathology; the highest accuracy of HSG was noted for uterine malformation and minimal accuracy was observed for intrauterine adhesions. Conclusions: Our experience supports the opinion that diagnostic hysteroscopy should be a first-line routine exam in infertility. Because of the high rate of false positive results for HSG in our study and considering the other studies in specialty literature, we always perform a diagnostic hysteroscopy before Assisted Human Reproduction procedures regardless of the HSG aspect. PMID:23483793

Testing for ROS1 in non-small cell lung cancer: a review with recommendations.

PubMed

Bubendorf, Lukas; Büttner, Reinhard; Al-Dayel, Fouad; Dietel, Manfred; Elmberger, Göran; Kerr, Keith; López-Ríos, Fernando; Marchetti, Antonio; Öz, Büge; Pauwels, Patrick; Penault-Llorca, Frédérique; Rossi, Giulio; Ryška, Aleš; Thunnissen, Erik

2016-11-01

Rearrangements of the ROS1 gene occur in 1-2 % of non-small cell lung cancers (NSCLCs). Crizotinib, a highly effective inhibitor of ROS1 kinase activity, is now FDA-approved for the treatment of patients with advanced ROS1-positive NSCLC. Consequently, focus on ROS1 testing is growing. Most laboratories currently rely on fluorescence in situ hybridisation (FISH) assays using a dual-colour break-apart probe to detect ROS1 rearrangements. Given the rarity of these rearrangements in NSCLC, detection of elevated ROS1 protein levels by immunohistochemistry may provide cost-effective screening prior to confirmatory FISH testing. Non-in situ testing approaches also hold potential as stand-alone methods or complementary tests, including multiplex real-time PCR assays and next-generation sequencing (NGS) platforms which include commercial test kits covering a range of fusion genes. In order to ensure high-quality biomarker testing, appropriate tissue handling, adequate control materials and participation in external quality assessment programmes are essential, irrespective of the testing technique employed. ROS1 testing is often only considered after negative tests for EGFR mutation and ALK gene rearrangement, based on the assumption that these oncogenic driver events tend to be exclusive. However, as the use of ROS1 inhibitors becomes routine, accurate and timely detection of ROS1 gene rearrangements will be critical for the optimal treatment of patients with NSCLC. As NGS techniques are introduced into routine diagnostic practice, ROS1 fusion gene testing will be provided as part of the initial testing package.

Human leukocyte antigen typing using buccal swabs as accurate and non-invasive substitute for venipuncture in children at risk for celiac disease.

PubMed

Adriaanse, Marlou P M; Vreugdenhil, Anita C E; Vastmans, Véronique; Groeneveld, Lisette; Molenbroeck, Stefan; Schott, Dina A; Voorter, Christina E M; Tilanus, Marcel G J

2016-10-01

Human leukocyte antigen (HLA) typing is an important step in the diagnostic algorithm for celiac disease (CD) and is also used for screening purposes. Collection of blood is invasive and accompanied with emotional impact especially in children. Genetic technological progress now enables HLA typing from buccal cell samples. This study evaluated the reliability and feasibility of HLA typing for CD-associated HLA polymorphisms using buccal swabs as routine test in high-risk individuals. Blood and buccal swabs of 77 children and adolescents with high risk for CD were prospectively collected in this cohort study. Buccal swab collection was performed either by the investigator at the outpatient clinic or by the patient or its parents at home. To evaluate the possibility of self-administration, three families performed the test at home. DNA was extracted using an adapted QIAamp method. Quantity, quality, and purity of DNA were recorded. HLA-DRB1, HLA-DQA1, and HLA-DQB1 typing was examined on buccal cell-derived and blood-derived DNA at low and, if necessary, high resolution level, using sequence-specific oligonucleotide and sequence-based typing, respectively. DNA isolation using buccal swabs yielded a good quality and sufficient quantity of DNA to perform HLA-DQ typing in all individuals. HLA typing results on buccal cell-derived DNA were identical to typing on blood-derived DNA, also for the self-administered samples. Introduction of the buccal swab test for HLA typing of CD risk in routine diagnostics can omit the current venipuncture and enables self-administration at home. Therefore, the buccal swab test is beneficial for individuals with a clinical suspicion for CD, as well as for screening purposes in high-risk populations. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

The MOAHLFA index of irritant sodium lauryl sulfate reactions: first results of a multicentre study on routine sodium lauryl sulfate patch testing.

PubMed

Uter, Wolfgang; Geier, Johannes; Becker, Detlef; Brasch, Jochen; Löffler, Harald

2004-01-01

In a multicentre study of the German Contact Dermatitis Research Group, sodium lauryl sulfate (SLS) 0.25% and 0.5% aq. has been added to routine allergen patch tests to assess its properties as a convenient diagnostic indicator of individual susceptibility to irritation at the time of patch testing. Previous studies indicated that irritant SLS reactivity may be related to individual factors such as age and sex. As these factors are, in turn, among the important predictors of contact allergy to many allergens, e.g. summarized in the 'MOAHLFA index', the impact of the MOAHLFA factors on irritant SLS patch test reactivity, and thus a potential for confounding, was assessed in the 5971 participating patients. As a result of 2 logistic regression analyses with an irritant reaction to 0.25% and 0.5% SLS, respectively, as outcome, male sex was identified as a relatively weak but significant risk factor (OR 1.38), while age 40 years or older was an even weaker risk factor (OR 1.22 and 1.15, respectively). Upon detailed analysis, no clear age gradient could, however, be identified. 1-day exposure time almost halved the odds of an irritant SLS reaction. In conclusion, this type of SLS patch test can be regarded as robust, indicating individual irritability relatively independent from the individual factors analysed here.

Custom oligonucleotide array-based CGH: a reliable diagnostic tool for detection of exonic copy-number changes in multiple targeted genes

PubMed Central

Vasson, Aurélie; Leroux, Céline; Orhant, Lucie; Boimard, Mathieu; Toussaint, Aurélie; Leroy, Chrystel; Commere, Virginie; Ghiotti, Tiffany; Deburgrave, Nathalie; Saillour, Yoann; Atlan, Isabelle; Fouveaut, Corinne; Beldjord, Cherif; Valleix, Sophie; Leturcq, France; Dodé, Catherine; Bienvenu, Thierry; Chelly, Jamel; Cossée, Mireille

2013-01-01

The frequency of disease-related large rearrangements (referred to as copy-number mutations, CNMs) varies among genes, and search for these mutations has an important place in diagnostic strategies. In recent years, CGH method using custom-designed high-density oligonucleotide-based arrays allowed the development of a powerful tool for detection of alterations at the level of exons and made it possible to provide flexibility through the possibility of modeling chips. The aim of our study was to test custom-designed oligonucleotide CGH array in a diagnostic laboratory setting that analyses several genes involved in various genetic diseases, and to compare it with conventional strategies. To this end, we designed a 12-plex CGH array (135k; 135 000 probes/subarray) (Roche Nimblegen) with exonic and intronic oligonucleotide probes covering 26 genes routinely analyzed in the laboratory. We tested control samples with known CNMs and patients for whom genetic causes underlying their disorders were unknown. The contribution of this technique is undeniable. Indeed, it appeared reproducible, reliable and sensitive enough to detect heterozygous single-exon deletions or duplications, complex rearrangements and somatic mosaicism. In addition, it improves reliability of CNM detection and allows determination of boundaries precisely enough to direct targeted sequencing of breakpoints. All of these points, associated with the possibility of a simultaneous analysis of several genes and scalability ‘homemade' make it a valuable tool as a new diagnostic approach of CNMs. PMID:23340513

Patterns of diagnostic marker assessment in adult diffuse glioma: a survey of the European Confederation of Neuropathological Societies (Euro-CNS)

PubMed Central

Woehrer, Adelheid; Kristensen, Bjarne W.; Vital, Anne; Hainfellner, Johannes A.

2017-01-01

The 2016 update of the WHO classification has introduced an integrated diagnostic approach that incorporates both tumor morphology and molecular information. This conceptual change has far-reaching implications, especially for neuropathologists who are in the forefront of translating molecular markers to routine diagnostic use. Adult diffuse glioma is a prototypic example for a group of tumors that underwent substantial regrouping, and it represents a major workload for surgical neuropathologists. Hence, we conducted a survey among members of the European Confederation of Neuropathological Societies (Euro-CNS) in order to assess 1) the extent to which molecular markers have already been incorporated in glioma diagnoses, 2) which molecular techniques are in daily use, and 3) to set a baseline for future surveys in this field. Based on 130 responses from participants across 40 nations neuropathologists uniformly rate molecular marker testing as highly relevant and already incorporate molecular information in their diagnostic assessments. At the same time however, the survey documents substantial differences in access to crucial biomarkers and molecular techniques across geographic regions and within individual countries. Concerns are raised concerning the validity of test assays with MGMT, 1p19q, and ATRX; being perceived as most problematic. Neuropathologists advocate the need for international harmonization of standards and consensus guidelines, and the majority is willing to actively engage in interlaboratory trials aiming at quality control (Figure 1). PMID:27966427

Adoption of recommended practices and basic technologies in a low-income setting

PubMed Central

English, Mike; Gathara, David; Mwinga, Stephen; Ayieko, Philip; Opondo, Charles; Aluvaala, Jalemba; Kihuba, Elesban; Mwaniki, Paul; Were, Fred; Irimu, Grace; Wasunna, Aggrey; Mogoa, Wycliffe; Nyamai, Rachel

2014-01-01

Objective In global health considerable attention is focused on the search for innovations; however, reports tracking their adoption in routine hospital settings from low-income countries are absent. Design and setting We used data collected on a consistent panel of indicators during four separate cross-sectional, hospital surveys in Kenya to track changes over a period of 11 years (2002–2012). Main outcome measures Basic resource availability, use of diagnostics and uptake of recommended practices. Results There appeared little change in availability of a panel of 28 basic resources (median 71% in 2002 to 82% in 2012) although availability of specific feeds for severe malnutrition and vitamin K improved. Use of blood glucose and HIV testing increased but remained inappropriately low throughout. Commonly (malaria) and uncommonly (lumbar puncture) performed diagnostic tests frequently failed to inform practice while pulse oximetry, a simple and cheap technology, was rarely available even in 2012. However, increasing adherence to prescribing guidance occurred during a period from 2006 to 2012 in which efforts were made to disseminate guidelines. Conclusions Findings suggest changes in clinical practices possibly linked to dissemination of guidelines at reasonable scale. However, full availability of basic resources was not attained and major gaps likely exist between the potential and actual impacts of simple diagnostics and technologies representing problems with availability, adoption and successful utilisation. These findings are relevant to debates on scaling up in low-income settings and to those developing novel therapeutic or diagnostic interventions. PMID:24482351

The role of routine preoperative EUS when performed after contrast enhanced CT in the diagnostic work-up in patients suspected of pancreatic or periampullary cancer.

PubMed

Cieslak, Kasia P; van Santvoort, Hjalmar C; Vleggaar, Frank P; van Leeuwen, Maarten S; ten Kate, Fibo J; Besselink, Marc G; Molenaar, I Quintus

2014-01-01

In patients suspected of pancreatic or periampullary cancer, abdominal contrast-enhanced computed tomography (CT) is the standard diagnostic modality. A supplementary endoscopic ultrasonography (EUS) is often performed, although there is only limited evidence of its additional diagnostic value. The aim of the study is to evaluate the additional diagnostic value of EUS over CT in deciding on exploratory laparotomy in patients suspected of pancreatic or periampullary cancer. We retrospectively analyzed 86 consecutive patients who routinely underwent CT and EUS before exploratory laparotomy with or without pancreatoduodenectomy for suspected pancreatic or periampullary carcinoma between 2007 and 2010. Primary outcomes were visibility of a mass, resectability on CT/EUS and resection with curative intent. A mass was visible on CT in 72/86 (84%) patients. In these 72 patients, EUS demonstrated a mass in 64/72 (89%) patients. Resectability was accurately predicted by CT in 65/72 (90%) and by EUS in 58/72 (81%) patients. In 14/86 (16%) patients no mass was seen on CT. EUS showed a mass in 12/14 (86%) of these patients. A malignant lesion was histological proven in 11/12 (92%) of these patients. Overall, resectability was accurately predicted by CT and EUS in 90% (77/86) and 84% (72/86), respectively. In patients with a visible mass on CT, suspected for pancreatic or periampullary cancer, EUS has no additional diagnostic value, does not influence the decision to perform laparotomy and should therefore not be performed routinely. In patients without a visible mass on CT, EUS is useful to confirm the presence of a tumor. Copyright © 2014 IAP and EPC. Published by Elsevier B.V. All rights reserved.

Point-of-care tests for syphilis and yaws in a low-income setting - A qualitative study of healthcare worker and patient experiences.

PubMed

Marks, Michael; Esau, Tommy; Asugeni, Rowena; Harrington, Relmah; Diau, Jason; Toloka, Hilary; Asugeni, James; Ansbro, Eimhin; Solomon, Anthony W; Maclaren, David; Redman-Maclaren, Michelle; Mabey, David C W

2018-04-01

The human treponematoses comprise venereal syphilis and the three non-venereal or endemic treponematoses yaws, bejel, and pinta. Serological assays remain the most common diagnostic method for all treponemal infections. Point-of-care tests (POCTs) for syphilis and yaws allow testing without further development of infrastructure in populations where routine laboratory facilities are not available. Alongside the test's performance characteristics assessed through diagnostic evaluation, it is important to consider broader issues when rolling out a POCT. Experience with malaria POCT roll-out in sub-Saharan Africa has demonstrated that both healthcare worker and patient beliefs may play a major role in shaping the real-world use of POCTs. We conducted a qualitative study evaluating healthcare worker and patient perceptions of using a syphilis/yaws POCT in clinics in the East Malaita region of Malaita province in the Solomon Islands. Prior to the study serology was only routinely available at the local district hospital. The POCT was deployed in the outpatient and ante-natal departments of a district hospital and four rural health clinics served by the hospital. Each site was provided with training and an SOP on the performance, interpretation and recording of results. Treatment for those testing positive was provided, in line with Solomon Islands Ministry of Health and Medical Services' guidelines for syphilis and yaws respectively. Alongside the implementation of the POCT we facilitated semi-structured interviews with both nurses and patients to explore individuals' experiences and beliefs in relation to use of the POCT. Four main themes emerged in the interviews: 1) training and ease of performing the test; 2) time taken and ability to fit the test into a clinical workflow; 3) perceived reliability and trustworthiness of the test; and 4) level of the health care system the test was most usefully deployed. Many healthcare workers related their experience with the POCT to their experience using similar tests for malaria. Although the test was considered to take a relatively long time to perform the benefits of improved access to testing were considered positive by most healthcare workers. Qualitative data is needed to help inform better training packages to support the implementation of POCT in low-resource settings.

Advanced Imaging Adds Little Value in the Diagnosis of Femoroacetabular Impingement Syndrome.

PubMed

Cunningham, Daniel J; Paranjape, Chinmay S; Harris, Joshua D; Nho, Shane J; Olson, Steven A; Mather, Richard C

2017-12-20

Femoroacetabular impingement (FAI) syndrome is an increasingly recognized source of hip pain and disability in young active adults. In order to confirm the diagnosis, providers often supplement physical examination maneuvers and radiographs with intra-articular hip injection, magnetic resonance imaging (MRI), or magnetic resonance arthrography (MRA). Since diagnostic imaging represents the fastest rising cost segment in U.S. health care, there is a need for value-driven diagnostic algorithms. The purpose of this study was to identify cost-effective diagnostic strategies for symptomatic FAI, comparing history and physical examination (H&P) alone (utilizing only radiographic imaging) with supplementation with injection, MRI, or MRA. A simple-chain decision model run as a cost-utility analysis was constructed to assess the diagnostic value of the MRI, MRA, and injection that are added to the H&P and radiographs in diagnosing symptomatic FAI. Strategies were compared using the incremental cost-utility ratio (ICUR) with a willingness to pay (WTP) of $100,000/QALY (quality-adjusted life year). Direct costs were measured using the Humana database (PearlDiver). Diagnostic test accuracy, treatment outcome probabilities, and utilities were extracted from the literature. H&P with and without supplemental diagnostic injection was the most cost-effective. Adjunct injection was preferred in situations with a WTP of >$60,000/QALY, low examination sensitivity, and high FAI prevalence. With low disease prevalence and low examination sensitivity, as may occur in a general practitioner's office, H&P with injection was the most cost-effective strategy, whereas in the reciprocal scenario, H&P with injection was only favored at exceptionally high WTP (∼$990,000). H&P and radiographs with supplemental diagnostic injection are preferred over advanced imaging, even with reasonable deviations from published values of disease prevalence, test sensitivity, and test specificity. Providers with low examination sensitivity in situations with low disease prevalence may benefit most from including injection in their diagnostic strategy. Providers with high examination sensitivity in situations with high disease prevalence may not benefit from including injection in their diagnostic strategy. Providers should not routinely rely on advanced imaging to diagnose FAI syndrome, although advanced imaging may have a role in challenging clinical scenarios. Economic and Decision Analysis Level IV. See Instructions for Authors for a complete description of levels of evidence.

LPA or GeneXpert in the diagnosis of multidrug-resistant tuberculosis.

PubMed

Mindru, Roxana; Spinu, Victor; Popescu, Oana

2016-01-01

Facing a constant increase of multidrug-resistant tuberculosis (MDR-TB), there is large need for routine use of new diagnostic tests, based on molecular techniques that allow both a rapid diagnosis for TB complex and rapid identification of resistance mutations. The resistances are due to genetic factors: accumulation of changes within the genome structure, acquisition or loss of genes, spontaneous mutations in chromosomal genes, and changes that induce selection of resistant strains during a suboptimal treatment. The bacteriology laboratory plays a crucial role in the making of the diagnosis, monitoring and preventing TB transmission. World Health Organization offers consistent recommendations in favour of use of Xpert MTB/RIF, GeneXpert platform, as initial diagnostic test in adults and children suspected of TB, because it can simultaneously determine the presence of Mycobacterium tuberculosis and the Rifampicin resistance, which is a surrogate marker of MDR strains. The very high sensibility and specificity, also in the smear negative samples, as well as the short time needed for the results, make Xpert MTB/RIF a valuable tool in the fight against TB. Other recommended tests are: LPA, which identifies M. Tuberculosis complex, the Rifancim and Isoniazid resistance; MTBDR plus or, for second line anti-TB drugs, the MTBDRsl.

First results with a lab-on-a-chip system for a fast Phytophthora diagnosis.

Treesearch

Sonja Horatzek; Stephan König; Stefan Wagner; Sabine Werres; Lydia Schwenkbier; Karina Weber; Jörg. Weber

2013-01-01

For Phytophthora spp. that are quarantine or regulated organisms, highly specific and sensitive diagnostic tools are recommended for surveys and monitoring. Furthermore, these diagnostic techniques should give results within a short time and should be not be too expensive. The techniques currently used for routine diagnosis of ...

SMASH: A Diagnostic Tool to Monitor Student Metacognition, Affect, and Study Habits in an Undergraduate Science Course

ERIC Educational Resources Information Center

Metzger, Kelsey J.; Smith, Brittany A.; Brown, Ethan; Soneral, Paula A. G.

2018-01-01

This study describes the development and implementation of an iterative diagnostic and intervention routine designed to elicit and quantitatively describe aspects of student metacognition, affect, and study habits in a first-year undergraduate biology course. The Student Metacognition, Affect, and Study Habits (SMASH) inventory is a…

Gonorrhoea Diagnostic and Treatment Uncertainties: Risk Factors for Culture Negative Confirmation after Positive Nucleic Acid Amplification Tests.

PubMed

Vyth, Rebecka; Leval, Amy; Eriksson, Björn; Ericson, Eva-Lena; Marions, Lena; Hergens, Maria-Pia

2016-01-01

Gonorrhoea incidence has increased substantially in Stockholm during the past years. These increases have coincided with changes in testing practice from solely culture-based to nucleic acid amplification tests (NAAT). Gonorrhoea NAAT is integrated with Chlamydia trachomatis testing and due to opportunistic screening for chlamydia, testing prevalence for gonorrhoea has increased substantially in the Stockholm population. The aim of this study was to examine epidemiological risk-factors for discordant case which are NAAT positive but culture negative. These discordant cases are especially problematic as they give rise to diagnostic and treatment uncertainties with risk for subsequent sequelae. All gonorrhoea cases from Stockholm county during 2011-2012 with at least one positive N. gonorrhoea NAAT test and follow-up cultures were included (N = 874). Data were analysed using multivariate and stratified logistic regression models. Results showed that women were 4-times more likely (OR 4.9; 95% CI 2.4-6.7) than men to have discordant cultures. Individuals tested for gonorrhoea without symptoms were 2.3 times more likely (95% CI 1.5-3.5) than those with symptoms to be discordant. NAAT method and having one week or more between NAAT and culture testing were also indicative of an increased likelihood for discordance. Using NAAT should be based on proper clinical or epidemiological indications and, when positive, followed-up with a culture-based test within one week if possible. Routine gonorrhoea testing is not recommended in low prevalence populations.

Gonorrhoea Diagnostic and Treatment Uncertainties: Risk Factors for Culture Negative Confirmation after Positive Nucleic Acid Amplification Tests

PubMed Central

Vyth, Rebecka; Leval, Amy; Eriksson, Björn; Ericson, Eva-Lena; Marions, Lena; Hergens, Maria-Pia

2016-01-01

Gonorrhoea incidence has increased substantially in Stockholm during the past years. These increases have coincided with changes in testing practice from solely culture-based to nucleic acid amplification tests (NAAT). Gonorrhoea NAAT is integrated with Chlamydia trachomatis testing and due to opportunistic screening for chlamydia, testing prevalence for gonorrhoea has increased substantially in the Stockholm population. The aim of this study was to examine epidemiological risk-factors for discordant case which are NAAT positive but culture negative. These discordant cases are especially problematic as they give rise to diagnostic and treatment uncertainties with risk for subsequent sequelae. All gonorrhoea cases from Stockholm county during 2011–2012 with at least one positive N. gonorrhoea NAAT test and follow-up cultures were included (N = 874). Data were analysed using multivariate and stratified logistic regression models. Results showed that women were 4-times more likely (OR 4.9; 95% CI 2.4–6.7) than men to have discordant cultures. Individuals tested for gonorrhoea without symptoms were 2.3 times more likely (95% CI 1.5–3.5) than those with symptoms to be discordant. NAAT method and having one week or more between NAAT and culture testing were also indicative of an increased likelihood for discordance. Using NAAT should be based on proper clinical or epidemiological indications and, when positive, followed-up with a culture-based test within one week if possible. Routine gonorrhoea testing is not recommended in low prevalence populations. PMID:27152704

Self Diagnostic Accelerometer for Mission Critical Health Monitoring of Aircraft and Spacecraft Engines

NASA Technical Reports Server (NTRS)

Lekki, John; Tokars, Roger; Jaros, Dave; Riggs, M. Terrence; Evans, Kenneth P.; Gyekenyesi, Andrew

2009-01-01

A self diagnostic accelerometer system has been shown to be sensitive to multiple failure modes of charge mode accelerometers. These failures include sensor structural damage, an electrical open circuit and most importantly sensor detachment. In this paper, experimental work that was performed to determine the capabilities of a self diagnostic accelerometer system while operating in the presence of various levels of mechanical noise, emulating real world conditions, is presented. The results show that the system can successfully conduct a self diagnostic routine under these conditions.

[Diagnostic imaging of urolithiais. Current recommendations and new developments].

PubMed

Thalgott, M; Kurtz, F; Gschwend, J E; Straub, M

2015-07-01

Prevalence of urolithiasis is increasing in industrialized countries--in both adults and children, representing a unique diagnostic and therapeutic challenge. Risk-adapted diagnostic imaging currently means assessment with maximized sensitivity and specificity together with minimal radiation exposure. In clinical routine, imaging is performed by sonography, unenhanced computed tomography (NCCT) or intravenous urography (IVU) as well as plain kidney-ureter-bladder (KUB) radiographs. The aim of the present review is a critical guideline-based and therapy-aligned presentation of diagnostic imaging procedures for optimized treatment of urolithiasis considering the specifics in children and pregnant women.

Practical Considerations for Clinical PET/MR Imaging.

PubMed

Galgano, Samuel; Viets, Zachary; Fowler, Kathryn; Gore, Lael; Thomas, John V; McNamara, Michelle; McConathy, Jonathan

2018-01-01

Clinical PET/MR imaging is currently performed at a number of centers around the world as part of routine standard of care. This article focuses on issues and considerations for a clinical PET/MR imaging program, focusing on routine standard-of-care studies. Although local factors influence how clinical PET/MR imaging is implemented, the approaches and considerations described here intend to apply to most clinical programs. PET/MR imaging provides many more options than PET/computed tomography with diagnostic advantages for certain clinical applications but with added complexity. A recurring theme is matching the PET/MR imaging protocol to the clinical application to balance diagnostic accuracy with efficiency. Copyright © 2017 Elsevier Inc. All rights reserved.

Practical Considerations for Clinical PET/MR Imaging.

PubMed

Galgano, Samuel; Viets, Zachary; Fowler, Kathryn; Gore, Lael; Thomas, John V; McNamara, Michelle; McConathy, Jonathan

2017-05-01

Clinical PET/MR imaging is currently performed at a number of centers around the world as part of routine standard of care. This article focuses on issues and considerations for a clinical PET/MR imaging program, focusing on routine standard-of-care studies. Although local factors influence how clinical PET/MR imaging is implemented, the approaches and considerations described here intend to apply to most clinical programs. PET/MR imaging provides many more options than PET/computed tomography with diagnostic advantages for certain clinical applications but with added complexity. A recurring theme is matching the PET/MR imaging protocol to the clinical application to balance diagnostic accuracy with efficiency. Copyright © 2016 Elsevier Inc. All rights reserved.

Identification and differentiation of food-related bacteria: A comparison of FTIR spectroscopy and MALDI-TOF mass spectrometry.

PubMed

Wenning, Mareike; Breitenwieser, Franziska; Konrad, Regina; Huber, Ingrid; Busch, Ulrich; Scherer, Siegfried

2014-08-01

The food industry requires easy, accurate, and cost-effective techniques for microbial identification to ensure safe products and identify microbial contaminations. In this work, FTIR spectroscopy and MALDI-TOF mass spectrometry were assessed for their suitability and applicability for routine microbial diagnostics of food-related microorganisms by analyzing their robustness according to changes in incubation time and medium, identification accuracy and their ability to differentiate isolates down to the strain level. Changes in the protocol lead to a significantly impaired performance of FTIR spectroscopy, whereas they had only little effects on MALDI-TOF MS. Identification accuracy was tested using 174 food-related bacteria (93 species) from an in-house strain collection and 40 fresh isolates from routine food analyses. For MALDI-TOF MS, weaknesses in the identification of bacilli and pseudomonads were observed; FTIR spectroscopy had most difficulties in identifying pseudomonads and enterobacteria. In general, MALDI-TOF MS obtained better results (52-85% correct at species level), since the analysis of mainly ribosomal proteins is more robust and seems to be more reliable. FTIR spectroscopy suffers from the fact that it generates a whole-cell fingerprint and intraspecies diversity may lead to overlapping species borders which complicates identification. In the present study values between 56% and 67% correct species identification were obtained. On the opposite, this high sensitivity offers the opportunity of typing below the species level which was not possible using MALDI-TOF MS. Using fresh isolates from routine diagnostics, both techniques performed well with 88% (MALDI-TOF) and 75% (FTIR) correct identifications at species level, respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

Point-of-care tests for syphilis and yaws in a low-income setting – A qualitative study of healthcare worker and patient experiences

PubMed Central

Esau, Tommy; Asugeni, Rowena; Harrington, Relmah; Diau, Jason; Toloka, Hilary; Asugeni, James; Ansbro, Eimhin; Solomon, Anthony W.; Maclaren, David; Redman-Maclaren, Michelle; Mabey, David C. W.

2018-01-01

Introduction The human treponematoses comprise venereal syphilis and the three non-venereal or endemic treponematoses yaws, bejel, and pinta. Serological assays remain the most common diagnostic method for all treponemal infections. Point-of-care tests (POCTs) for syphilis and yaws allow testing without further development of infrastructure in populations where routine laboratory facilities are not available. Alongside the test’s performance characteristics assessed through diagnostic evaluation, it is important to consider broader issues when rolling out a POCT. Experience with malaria POCT roll-out in sub-Saharan Africa has demonstrated that both healthcare worker and patient beliefs may play a major role in shaping the real-world use of POCTs. We conducted a qualitative study evaluating healthcare worker and patient perceptions of using a syphilis/yaws POCT in clinics in the East Malaita region of Malaita province in the Solomon Islands. Prior to the study serology was only routinely available at the local district hospital. Methods The POCT was deployed in the outpatient and ante-natal departments of a district hospital and four rural health clinics served by the hospital. Each site was provided with training and an SOP on the performance, interpretation and recording of results. Treatment for those testing positive was provided, in line with Solomon Islands Ministry of Health and Medical Services’ guidelines for syphilis and yaws respectively. Alongside the implementation of the POCT we facilitated semi-structured interviews with both nurses and patients to explore individuals’ experiences and beliefs in relation to use of the POCT. Results and discussion Four main themes emerged in the interviews: 1) training and ease of performing the test; 2) time taken and ability to fit the test into a clinical workflow; 3) perceived reliability and trustworthiness of the test; and 4) level of the health care system the test was most usefully deployed. Many healthcare workers related their experience with the POCT to their experience using similar tests for malaria. Although the test was considered to take a relatively long time to perform the benefits of improved access to testing were considered positive by most healthcare workers. Qualitative data is needed to help inform better training packages to support the implementation of POCT in low-resource settings. PMID:29672524

Disinfection protocols for necropsy equipment in rabies laboratories: Safety of personnel and diagnostic outcome.

PubMed

Aiello, Roberta; Zecchin, Barbara; Tiozzo Caenazzo, Silvia; Cattoli, Giovanni; De Benedictis, Paola

2016-08-01

In the last decades, molecular techniques have gradually been adopted for the rapid confirmation of results obtained through gold standard methods. However, international organisations discourage their use in routine laboratory investigations for rabies post-mortem diagnosis, as they may lead to false positive results due to cross-contamination. Cleaning and disinfection are essential to prevent cross-contamination of samples in the laboratory environment. The present study evaluated the efficacy of selected disinfectants on rabies-contaminated necropsy equipment under organic challenge using a carrier-based test. The occurrence of detectable Rabies virus (RABV) antigen, viable virus and RNA was assessed through the gold standard Fluorescent Antibody Test, the Rabies Tissue Culture Infection Test and molecular techniques, respectively. None of the tested disinfectants proved to be effective under label conditions. Off label disinfection protocols were found effective for oxidizing agents and phenolic, only. Biguanide and quaternary ammonium compound were both ineffective under all tested conditions. Overall, discordant results were obtained when different diagnostic tests were compared, which means that in the presence of organic contamination common disinfectants may not be effective enough on viable RABV or RNA. Our results indicate that an effective disinfection protocol should be carefully validated to guarantee staff safety and reliability of results. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Application of the MALDI Biotyper to clinical microbiology: progress and potential.

PubMed

Kostrzewa, Markus

2018-03-01

The introduction of the MALDI Biotyper in laboratories substantially changed microbiology practice, this has been called a revolution. The system accelerated diagnostic while costs were reduced and accuracy was increased. In just a few years MALDI-TOF MS became the first-line identification tool for microorganisms. Ten years after its introduction, more than 2000 MALDI Biotyper systems are installed in laboratories which are performing routine diagnostic, and the number is still increasing. Areas covered: This article summarises changes in clinical microbiology introduced by the MALDI Biotyper and its effects, as it has been published in peer reviewed articles found in PubMed. Further, the potential of novel developments to increase the value of the system is described. Expert commentary: The MALDI Biotyper has significantly improved clinical microbiology in the area of microorganism identification. Now new developments and applications, e.g. for typing and resistance testing, might further increase its value in clinical microbiology. The systems might get the central diagnostic analyser which is getting integrated into the widely automated microbiology laboratories of the future.

A Diagnostic Approach for Electro-Mechanical Actuators in Aerospace Systems

NASA Technical Reports Server (NTRS)

Balaban, Edward; Saxena, Abhinav; Bansal, Prasun; Goebel, Kai Frank; Stoelting, Paul; Curran, Simon

2009-01-01

Electro-mechanical actuators (EMA) are finding increasing use in aerospace applications, especially with the trend towards all all-electric aircraft and spacecraft designs. However, electro-mechanical actuators still lack the knowledge base accumulated for other fielded actuator types, particularly with regard to fault detection and characterization. This paper presents a thorough analysis of some of the critical failure modes documented for EMAs and describes experiments conducted on detecting and isolating a subset of them. The list of failures has been prepared through an extensive Failure Modes and Criticality Analysis (FMECA) reference, literature review, and accessible industry experience. Methods for data acquisition and validation of algorithms on EMA test stands are described. A variety of condition indicators were developed that enabled detection, identification, and isolation among the various fault modes. A diagnostic algorithm based on an artificial neural network is shown to operate successfully using these condition indicators and furthermore, robustness of these diagnostic routines to sensor faults is demonstrated by showing their ability to distinguish between them and component failures. The paper concludes with a roadmap leading from this effort towards developing successful prognostic algorithms for electromechanical actuators.

Next generation sequencing--implications for clinical practice.

PubMed

Raffan, Eleanor; Semple, Robert K

2011-01-01

Genetic testing in inherited disease has traditionally relied upon recognition of the presenting clinical syndrome and targeted analysis of genes known to be linked to that syndrome. Consequently, many patients with genetic syndromes remain without a specific diagnosis. New 'next-generation' sequencing (NGS) techniques permit simultaneous sequencing of enormous amounts of DNA. A slew of research publications have recently demonstrated the tremendous power of these technologies in increasing understanding of human genetic disease. These approaches are likely to be increasingly employed in routine diagnostic practice, but the scale of the genetic information yielded about individuals means that caution must be exercised to avoid net harm in this setting. Use of NGS in a research setting will increasingly have a major but indirect beneficial impact on clinical practice. However, important technical, ethical and social challenges need to be addressed through informed professional and public dialogue before it finds its mature niche as a direct tool in the clinical diagnostic armoury.

Molecular diagnostics for the detection and characterization of microbial pathogens.

PubMed

Procop, Gary W

2007-09-01

New and advanced methods of molecular diagnostics are changing the way we practice clinical microbiology, which affects the practice of medicine. Signal amplification and real-time nucleic acid amplification technologies offer a sensitive and specific result with a more rapid turnaround time than has ever before been possible. Numerous methods of postamplification analysis afford the simultaneous detection and differentiation of numerous microbial pathogens, their mechanisms of resistance, and the construction of disease-specific assays. The technical feasibility of these assays has already been demonstrated. How these new, often more expensive tests will be incorporated into routine practice and the impact they will have on patient care remain to be determined. One of the most attractive uses for such techniques is to achieve a more rapid characterization of the infectious agent so that a narrower-spectrum antimicrobial agent may be used, which should have an impact on resistance patterns.

Epidemiology and diagnostic testing for meningitis in adults as the meningococcal epidemic declined at Middlemore Hospital.

PubMed

McBride, Stephen; Fulke, Jennifer; Giles, Hannah; Hobbs, Mark; Suh, Jun; Sathyendran, Vani; Thompson, Emily; Taylor, Susan; Holland, David

2015-03-13

To describe changes in epidemiology and diagnostic techniques for adult meningitis at Middlemore Hospital following the decline of the meningococcal epidemic. Retrospective audit of cases of meningitis from 2000 to 2009. Microbiologically-confirmed diagnosis (MCD) was established in 296 of 743 episodes (40%), most commonly enterovirus (123/296, 42%), Neisseria meningitidis (43/296, 15%) and Streptococcus pneumoniae (34/296, 11%). N. meningitidis meningitis declined and herpes viruses increased over time, without significant change in overall meningitis case numbers. By 2009, S. pneumoniae constituted a greater proportion of cases than N. meningitidis. Cerebrospinal fluid (CSF) polymerase chain reaction (PCR) and pneumococcal immunochromatographic testing (PICT) increased over time as did the proportion of cases with MCD. CSF Gram stain was positive in 45% (53/118) and CSF culture made MCD in 37% (44/118) of confirmed bacterial episodes (CBE). PCR provided MCD in 59% (26/54) of CBE and 99% (168/170) of viral episodes. CSF PICT was tested in 76% (26/34) of S. pneumoniae meningitis (positive in 92% (24/26). As the epidemic waned, local incidence of meningococcal meningitis decreased without significant decreasing meningitis overall. Empiric treatment for meningitis in New Zealand adults should routinely include pneumococcal cover. Increased PCR testing increases MCD in meningitis.

Neutral helium beam probe

NASA Astrophysics Data System (ADS)

Karim, Rezwanul

1999-10-01

This article discusses the development of a code where diagnostic neutral helium beam can be used as a probe. The code solves numerically the evolution of the population densities of helium atoms at their several different energy levels as the beam propagates through the plasma. The collisional radiative model has been utilized in this numerical calculation. The spatial dependence of the metastable states of neutral helium atom, as obtained in this numerical analysis, offers a possible diagnostic tool for tokamak plasma. The spatial evolution for several hypothetical plasma conditions was tested. Simulation routines were also run with the plasma parameters (density and temperature profiles) similar to a shot in the Princeton beta experiment modified (PBX-M) tokamak and a shot in Tokamak Fusion Test Reactor tokamak. A comparison between the simulation result and the experimentally obtained data (for each of these two shots) is presented. A good correlation in such comparisons for a number of such shots can establish the accurateness and usefulness of this probe. The result can possibly be extended for other plasma machines and for various plasma conditions in those machines.

Serum osmolality and effects of water deprivation in captive Asian elephants (Elephas maximus).

PubMed

Hall, Natalie H; Isaza, Ramiro; Hall, James S; Wiedner, Ellen; Conrad, Bettina L; Wamsley, Heather L

2012-07-01

Serum from 21 healthy, captive Asian elephants (Elephas maximus) was evaluated by measured and calculated osmolality. Serum osmolality results for this population of Asian elephants had a median of 261 mOsm/kg and an interquartile interval of 258-269 mOsm/kg when measured by freezing point osmometry and a median of 264 mOsm/kg and an interquartile interval of 257-269 mOsm/kg when measured by vapor pressure osmometry. These values are significantly lower than values reported in other mammalian species and have important diagnostic and therapeutic implications. Calculated osmolality produced unreliable results and needs further study to determine an appropriate formula and its clinical application in this species. A 16-hr water deprivation test in 16 Asian elephants induced a small, subclinical, but statistically significant increase in measured serum osmolality. Serum osmolality, blood urea nitrogen, and total protein by refractometer were sensitive indicators of hydration status. Serum osmolality measurement by freezing point or vapor pressure osmometry is a useful adjunct to routine clinical tests in the diagnostic evaluation of elephants.

IAC Standardized Reporting of Breast Fine-Needle Aspiration Biopsy Cytology.

PubMed

Field, Andrew S; Schmitt, Fernando; Vielh, Philippe

2017-01-01

There have been many changes in the roles of fine-needle aspiration biopsy (FNAB) and core needle biopsy (CNB) in the diagnostic workup of breast lesions in routine breast clinics and in mammographic breast screening programs, as well as changes in the management algorithms utilized and the treatments available, since the NCI consensus on breast FNAB cytology in 1996. A standardized approach will improve training and performance of FNAB and smear-making techniques, and structured reporting will improve the quality and reproducibility of reports across departments, cities and countries providing a basis for quality assurance measures and improving patient care and facilitating research. Linking cytology reports to management algorithms will increase the clinicians' use of FNAB cytology and where appropriate CNB, and enhance the use of ancillary tests for prognostic testing. The IAC recognizes that the local medical infrastructure and resources for breast imaging, biopsy and treatment will influence the diagnostic workup and management of breast disease, but best practice guidelines should be established and modified as required. © 2016 S. Karger AG, Basel.

Asymptomatic malaria parasitaemia using rapid diagnostic test in unbooked pregnant women in rural Ondo-south district, Nigeria.

PubMed

Nwaneri, D U; Adeleye, O A; Ande, A B

2013-03-01

Malaria is a major contributor of maternal and peri-natal morbidity and mortality. The disease may be asymptomatic despite sequestration of parasitized red blood cells in the placental micro-circulation with antecedent complications. In such condition, it may also be difficult to identify the malaria parasite by the peripheral blood film microscopy, thus the need for use of simple but reliable tool for malaria parasite diagnosis. To determine the prevalence of asymptomatic malaria parasitaemia using the Rapid Diagnostic Test in pregnant unbooked women seen in a primary health centre during a malaria control campaign programme in rural Ondo-south, District Nigeria. Prevalence of asymptomatic malaria parasitaemia was 25.9%. Only 3 (3.5%) of the 85 women had the long lasting insecticide-treated nets. There was no significant association between malaria parasitaemia, and the age group, parity and gestation age. Given the high prevalence of asymptomatic malaria in pregnancy, routine screening for malaria at booking and scaling-up of other malaria control strategies such as the use of long lasting insecticidal-treated nets and intermittent preventive therapy for pregnant women are recommended.

Serum osmolality and effects of water deprivation in captive Asian elephants (Elephas maximus)

PubMed Central

Hall, Natalie H.; Isaza, Ramiro; Hall, James S.; Wiedner, Ellen; Conrad, Bettina L.; Wamsley, Heather L.

2013-01-01

Serum from 21 healthy, captive Asian elephants (Elephas maximus) was evaluated by measured and calculated osmolality. Serum osmolality results for this population of Asian elephants had a median of 261 mOsm/kg and an interquartile interval of 258–269 mOsm/kg when measured by freezing point osmometry and a median of 264 mOsm/kg and an interquartile interval of 257–269 mOsm/kg when measured by vapor pressure osmometry. These values are significantly lower than values reported in other mammalian species and have important diagnostic and therapeutic implications. Calculated osmolality produced unreliable results and needs further study to determine an appropriate formula and its clinical application in this species. A 16-hr water deprivation test in 16 Asian elephants induced a small, subclinical, but statistically significant increase in measured serum osmolality. Serum osmolality, blood urea nitrogen, and total protein by refractometer were sensitive indicators of hydration status. Serum osmolality measurement by freezing point or vapor pressure osmometry is a useful adjunct to routine clinical tests in the diagnostic evaluation of elephants. PMID:22643341

Sensitivity and specificity of the amer dizziness diagnostic scale (adds) for patients with vestibular disorders.

PubMed

Al Saif, Amer; Alsenany, Samira

2015-01-01

[Purpose] To investigate the sensitivity and specificity of a newly developed diagnostic tool, the Amer Dizziness Diagnostic Scale (ADDS), to evaluate and differentially diagnose vestibular disorder and to identify the strengths and weaknesses of the scale and its usefulness in clinical practice. [Subjects and Methods] Two hundred subjects of both genders (72 males, 128 females) aged between 18 to 60 (49.5±7.8) who had a history of vertigo and/or dizziness symptoms for this previous two weeks or less were recruited for the study. All subjects were referred by otolaryngologists, neurologists or family physicians in and around Jeddah, Kingdom of Saudi Arabia. On the first clinic visit, all the patients were evaluated once using the ADDS, following which they underwent routine testing of clinical signs and symptoms, audiometry, and a neurological examination, coupled with tests of Vestibulo-Ocular Reflex function, which often serves as the "gold standard" for determining the probability of a vestibular deficit. [Results] The results show that the ADDS strongly correlated with "true-positive" and "true-negative" responses for determining the probability of a vestibular disorder (r =0.95). A stepwise linear regression was conducted and the results indicate that the ADDS was a significant predictor of "true-positive" and "true-negative" responses in vestibular disorders (R(2) =0.90). Approximately 90% of the variability in the vestibular gold standard test was explained by its relationship to the ADDS. Moreover, the ADDS was found to have a sensitivity of 96% and a specificity of 96%. [Conclusion] This study showed that the Amer Dizziness Diagnostic Scale has high sensitivity and specificity and that it can be used as a method of differential diagnosis for patients with vestibular disorders.

A Case Report of Post-Operative Jöd-Basedow Phenomennon Following Oral and IV Iodine Contrast Administration

PubMed Central

Hull, Erroll; Lujan, Eugenio

2014-01-01

This is a case of thyrotoxicosis, due to the Jöd-Basedow phenomenon following administration of oral and IV iodinated contrast in a patient with history of gastrointestinal stromal tumor (GIST) and small bowel obstruction. The patient developed atrial fibrillation and had an extended stay in the intensive care unit. Given the aging population with possible subclinical hyperthyroidism, multinodular goiter, and the rise in contrast administration for routine diagnostic studies, this case serves to raise awareness of the risks of “routine” tests administered to our aging patient population. PMID:24716009

[Validation of an in-house method for the determination of zinc in serum: Meeting the requirements of ISO 17025].

PubMed

Llorente Ballesteros, M T; Navarro Serrano, I; López Colón, J L

2015-01-01

The aim of this report is to propose a scheme for validation of an analytical technique according to ISO 17025. According to ISO 17025, the fundamental parameters tested were: selectivity, calibration model, precision, accuracy, uncertainty of measurement, and analytical interference. A protocol has been developed that has been applied successfully to quantify zinc in serum by atomic absorption spectrometry. It is demonstrated that our method is selective, linear, accurate, and precise, making it suitable for use in routine diagnostics. Copyright © 2015 SECA. Published by Elsevier Espana. All rights reserved.

Efficacy of a chairside diagnostic test kit for estimation of C-reactive protein levels in periodontal disease.

PubMed

Nagarale, Girish; Ravindra, S; Thakur, Srinath; Setty, Swati

2010-10-01

C-reactive protein [CRP] levels increase to hundreds of mg/mL within hours following infection. Studies have shown that serum CRP levels were elevated in periodontal disease. However, in all the previous studies, CRP levels were measured by using high-sensitivity CRP assay kits with minimal detection limits of 0.1 to 3 mg/L, which was much below the normal value of 10 mg/L. These high-sensitivity CRP assays need a proper laboratory setup, and these methods cannot be used as a routine chair-side test in the dental office. The purpose of this study was to investigate the serum CRP levels in subjects with periodontal disease by using a rapid chair-side diagnostic test kit with a lower detection limit of 6 mg/L and to compare the CRP levels before and after periodontal therapy. A total of 45 systemically healthy subjects were selected for the study. Subjects were divided into three groups: group A: healthy controls, group B: gingivitis, group C: periodontitis. Serum levels of CRP were determined by using a latex slide agglutination method with commercially available kit with lower detection limit of 6 mg/L. CRP was negative in all the 15 subjects in groups A and B at baseline, 7th and 30th day. CRP was positive only in 2 subjects in Group C at baseline and 7th day. Estimation of serum CRP by using a rapid chair-side diagnostic test kit is not of any significance in subjects with periodontitis.

Efficacy of a chairside diagnostic test kit for estimation of C-reactive protein levels in periodontal disease

PubMed Central

Nagarale, Girish; Ravindra, S.; Thakur, Srinath; Setty, Swati

2010-01-01

Background: C-reactive protein [CRP] levels increase to hundreds of mg/mL within hours following infection. Studies have shown that serum CRP levels were elevated in periodontal disease. However, in all the previous studies, CRP levels were measured by using high-sensitivity CRP assay kits with minimal detection limits of 0.1 to 3 mg/L, which was much below the normal value of 10 mg/L. These high-sensitivity CRP assays need a proper laboratory setup, and these methods cannot be used as a routine chair-side test in the dental office. Aim: The purpose of this study was to investigate the serum CRP levels in subjects with periodontal disease by using a rapid chair-side diagnostic test kit with a lower detection limit of 6 mg/L and to compare the CRP levels before and after periodontal therapy. Materials and Methods: A total of 45 systemically healthy subjects were selected for the study. Subjects were divided into three groups: group A: healthy controls, group B: gingivitis, group C: periodontitis. Serum levels of CRP were determined by using a latex slide agglutination method with commercially available kit with lower detection limit of 6 mg/L. Results: CRP was negative in all the 15 subjects in groups A and B at baseline, 7th and 30th day. CRP was positive only in 2 subjects in Group C at baseline and 7th day. Conclusion: Estimation of serum CRP by using a rapid chair-side diagnostic test kit is not of any significance in subjects with periodontitis. PMID:21731244

How Do Patients and Health Workers Interact around Malaria Rapid Diagnostic Testing, and How Are the Tests Experienced by Patients in Practice? A Qualitative Study in Western Uganda

PubMed Central

Altaras, Robin; Nuwa, Anthony; Agaba, Bosco; Streat, Elizabeth; Tibenderana, James K.; Martin, Sandrine; Strachan, Clare E.

2016-01-01

Background Successful scale-up in the use of malaria rapid diagnostic tests (RDTs) requires that patients accept testing and treatment based on RDT results and that healthcare providers treat according to test results. Patient-provider communication is a key component of quality care, and leads to improved patient satisfaction, higher adherence to treatment and better health outcomes. Voiced or perceived patient expectations are also known to influence treatment decision-making among healthcare providers. While there has been a growth in literature on provider practices around rapid testing for malaria, there has been little analysis of inter-personal communication around the testing process. We investigated how healthcare providers and patients interact and engage throughout the diagnostic and treatment process, and how the testing service is experienced by patients in practice. Methods This research was conducted alongside a larger study which explored determinants of provider treatment decision-making following negative RDT results in a rural district (Kibaale) in mid-western Uganda, ten months after RDT introduction. Fifty-five patients presenting with fever were observed during routine outpatient visits at 12 low-level public health facilities. Observation captured communication practices relating to test purpose, results, diagnosis and treatment. All observed patients or caregivers were immediately followed up with in-depth interview. Analysis followed the ‘framework’ approach. A summative approach was also used to analyse observation data. Results Providers failed to consistently communicate the reasons for carrying out the test, and particularly to RDT-negative patients, a diagnostic outcome or the meaning of test results, also leading to confusion over what the test can detect. Patients appeared to value testing, but were frustrated by the lack of communication on outcomes. RDT-negative patients were dissatisfied by the absence of information on an alternative diagnosis and expressed uncertainty around adequacy of proposed treatment. Conclusions Poor provider communication practices around the testing process, as well as limited inter-personal exchange between providers and patients, impacted on patients’ perceptions of their proposed treatment. Patients have a right to health information and may be more likely to accept and adhere to treatment when they understand their diagnosis and treatment rationale in relation to their perceived health needs and visit expectations. PMID:27494507

Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool.

PubMed

Mesquita, Flávio da Silva; Oliveira, Danielle Bruna Leal de; Crema, Daniela; Pinez, Célia Miranda Nunes; Colmanetti, Thaís Cristina; Thomazelli, Luciano Matsumia; Gilio, Alfredo Elias; Vieira, Sandra Elisabeth; Martinez, Marina Baquerizo; Botosso, Viviane Fongaro; Durigon, Edison Luiz

The aim of this study was to evaluate the QuickVue ® RSV Test Kit (QUIDEL Corp, CA, USA) as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue ® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. From 313 positive samples by immunofluorescence assays, 282 (90%) were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue ® RSV Test and viral load or specific strain. The QuickVue ® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. This study demonstrated that the QuickVue ® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

The agony of choice in dermatophyte diagnostics-performance of different molecular tests and culture in the detection of Trichophyton rubrum and Trichophyton interdigitale.

PubMed

Kupsch, C; Ohst, T; Pankewitz, F; Nenoff, P; Uhrlaß, S; Winter, I; Gräser, Y

2016-08-01

Dermatophytosis caused by dermatophytes of the genera Trichophyton and Microsporum belong to the most frequent mycoses worldwide. Molecular detection methods proved to be highly sensitive and enable rapid and accurate detection of dermatophyte species from clinical specimens. For the first time, we compare the performance of different molecular methods with each other and with conventional diagnostics in the detection of dermatophytoses caused by Trichophyton rubrum and Trichophyton interdigitale in clinical specimens (nail, skin and hair). The compared molecular methods comprise two already published PCR-ELISAs, a published quantitative RT-PCR as well as a newly developed PCR-ELISA targeting the internal transcribed spacer region. We investigated the sensitivity of the assays by analysing 375 clinical samples. In 148 specimens (39.5%) a positive result was gained in at least one of the four molecular tests or by culture, but the number of detected agents differed significantly between some of the assays. The most sensitive assay, a PCR-ELISA targeting a microsatellite region, detected 81 T. rubrum infections followed by an internal transcribed spacer PCR-ELISA (60), quantitative RT-PCR (52) and a topoisomerase II PCR-ELISA (51), whereas cultivation resulted in T. rubrum identification in 37 samples. The pros and cons of all four tests in routine diagnostics are discussed. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

1998 Technology Showcase. JOAP International Condition Monitoring Conference.

DTIC Science & Technology

1998-04-01

Systems using Automated SEM/ EDX and New Diagnostic Routines 276 N. W Farrant & T. Luckhurst ADVANCED DIAGNOSTIC SYSTEMS Model-Based Diagnostics of Gas...Microscopy with Energy Dispersive X-Ray (SEM/ EDX ) micro analysis packages and Energy Dispersive X-Ray Fluorescence (EDXRF) analytical equipment. Therqfore...wear particles separated by ferrogram method. a- I WEAR PARTICLE A SLAS 97 (HOME PAGE) Fig I Home Page NONFE;RROUS MATERIAL A wW~ a48 -1, rV fr , ý b

Comparison of Saramis 4.12 and IVD 3.0 Vitek MS Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Identification of Mycobacteria from Solid and Liquid Culture Media.

PubMed

Leyer, Caroline; Gregorowicz, Guillaume; Mougari, Faiza; Raskine, Laurent; Cambau, Emmanuelle; de Briel, Dominique

2017-07-01

During the last decade, many investigators have studied matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for identification of mycobacteria. Diverse and contradictory results indicated that optimal level for routine testing has not been reached yet. This work aimed to assess Vitek MS through two distinct versions, Saramis v4.12 RUO and the IVD v3.0, under conditions close to routine laboratory practice. Overall, 111 mycobacterial isolates were subjected to protein extraction and same spectra were matched against both databases. The IVD v3.0 database proved to be superior to Saramis v4.12 and its identification rates remarkably increased, from 67% to 94% for isolates grown on Middlebrook 7H10 solid medium and from 62% to 91% for isolates grown on mycobacterial growth indicator tube (MGIT) liquid medium. With this new version, IVD v3.0, MALDI-TOF MS might be integrated into routine clinical diagnostics, although molecular techniques remain mandatory in some cases. Copyright © 2017 American Society for Microbiology.

Meta-Review of CSF Core Biomarkers in Alzheimer’s Disease: The State-of-the-Art after the New Revised Diagnostic Criteria

PubMed Central

Ferreira, Daniel; Perestelo-Pérez, Lilisbeth; Westman, Eric; Wahlund, Lars-Olof; Sarría, Antonio; Serrano-Aguilar, Pedro

2014-01-01

Background: Current research criteria for Alzheimer’s disease (AD) include cerebrospinal fluid (CSF) biomarkers into the diagnostic algorithm. However, spreading their use to the clinical routine is still questionable. Objective: To provide an updated, systematic and critical review on the diagnostic utility of the CSF core biomarkers for AD. Data sources: MEDLINE, PreMedline, EMBASE, PsycInfo, CINAHL, Cochrane Library, and CRD. Eligibility criteria: (1a) Systematic reviews with meta-analysis; (1b) Primary studies published after the new revised diagnostic criteria; (2) Evaluation of the diagnostic performance of at least one CSF core biomarker. Results: The diagnostic performance of CSF biomarkers is generally satisfactory. They are optimal for discriminating AD patients from healthy controls. Their combination may also be suitable for mild cognitive impairment (MCI) prognosis. However, CSF biomarkers fail to distinguish AD from other forms of dementia. Limitations: (1) Use of clinical diagnosis as standard instead of pathological postmortem confirmation; (2) variability of methodological aspects; (3) insufficiently long follow-up periods in MCI studies; and (4) lower diagnostic accuracy in primary care compared with memory clinics. Conclusion: Additional work needs to be done to validate the application of CSF core biomarkers as they are proposed in the new revised diagnostic criteria. The use of CSF core biomarkers in clinical routine is more likely if these limitations are overcome. Early diagnosis is going to be of utmost importance when effective pharmacological treatment will be available and the CSF core biomarkers can also be implemented in clinical trials for drug development. PMID:24715863

Diagnostic Value of Bronchoalveolar Lavage for Diagnosis of Suspected Peripheral Lung Cancer.

PubMed

Bezel, Pascal; Tischler, Verena; Robinson, Cecile; Baumueller, Stephan; Bode-Lesniewska, Beata; Kohler, Malcolm; Freitag, Lutz; Franzen, Daniel

2016-09-01

There is a paucity of data concerning the benefit of bronchoalveolar lavage (BAL) for the diagnosis of suspected peripheral lung cancer (PLC). The aim of this study was to investigate the diagnostic value of BAL for the diagnosis of suspected PLC. All flexible bronchoscopies that included BAL among other modalities (brush, forceps, washing) for the diagnosis of a suspected PLC performed between 2009 and 2013 were analyzed in this retrospective study. A total of 260 patients were included. Malignancy was present in 61%. BAL's sensitivity for the diagnosis of malignancy was 29%, and overall diagnostic yield of BAL was 46%. However, only 1% of cancer diagnoses would have been missed in the absence of BAL. In the multivariable analysis, the size of lesion (odds ratio [OR], 1.17; 95% confidence interval [CI], 1.02-1.33; P = .023), the presence of bronchus sign (OR, 4.73; 95% CI, 1.06-21.08; P = .042), and the presence of mediastinal/hilar lymphadenopathy (OR, 3.37; 95% CI, 1.53-7.41; P = .002) were associated with improved BAL true-positive ratio relating to diagnosis of malignancy. However, the effect of lesion size on sensitivity was small (area under the curve, 0.31; 95% CI, 0.23-0.40; P < .001). Ground-glass lesions were not associated with improved BAL diagnostic value. The number needed to test for BAL for the diagnosis of malignancy or pulmonary infection was 37. Conventional BAL has a low diagnostic value for the diagnosis of suspected PLC, and the low number needed to test does not qualify BAL as a recommended routine investigation for the diagnosis of suspected PLC for either solid or ground-glass lesions. Copyright © 2016 Elsevier Inc. All rights reserved.

Validation of α-Synuclein as a CSF Biomarker for Sporadic Creutzfeldt-Jakob Disease.

PubMed

Llorens, Franc; Kruse, Niels; Karch, André; Schmitz, Matthias; Zafar, Saima; Gotzmann, Nadine; Sun, Ting; Köchy, Silja; Knipper, Tobias; Cramm, Maria; Golanska, Ewa; Sikorska, Beata; Liberski, Pawel P; Sánchez-Valle, Raquel; Fischer, Andre; Mollenhauer, Brit; Zerr, Inga

2018-03-01

The analysis of cerebrospinal fluid (CSF) biomarkers gains importance in the differential diagnosis of prion diseases. However, no single diagnostic tool or combination of them can unequivocally confirm prion disease diagnosis. Electrochemiluminescence (ECL)-based immunoassays have demonstrated to achieve high diagnostic accuracy in a variety of sample types due to their high sensitivity and dynamic range. Quantification of CSF α-synuclein (a-syn) by an in-house ECL-based ELISA assay has been recently reported as an excellent approach for the diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD), the most prevalent form of human prion disease. In the present study, we validated a commercially available ECL-based a-syn ELISA platform as a diagnostic test for correct classification of sCJD cases. CSF a-syn was analysed in 203 sCJD cases with definite diagnosis and in 445 non-CJD cases. We investigated reproducibility and stability of CSF a-syn and made recommendations for its analysis in the sCJD diagnostic workup. A sensitivity of 98% and a specificity of 97% were achieved when using an optimal cut-off of 820 pg/mL a-syn. Moreover, we were able to show a negative correlation between a-syn levels and disease duration suggesting that CSF a-syn may be a good prognostic marker for sCJD patients. The present study validates the use of a-syn as a CSF biomarker of sCJD and establishes the clinical and pre-analytical parameters for its use in differential diagnosis in clinical routine. Additionally, the current test presents some advantages compared to other diagnostic approaches: it is fast, economic, requires minimal amount of CSF and a-syn levels are stable along disease progression.

Malaria rapid diagnostic test transport and storage conditions in Burkina Faso, Senegal, Ethiopia and the Philippines

PubMed Central

2012-01-01

Background As more point of care diagnostics become available, the need to transport and store perishable medical commodities to remote locations increases. As with other diagnostics, malaria rapid diagnostic tests (RDTs) must be highly reliable at point of use, but exposure to adverse environmental conditions during distribution has the potential to degrade tests and accuracy. In remote locations, poor quality diagnostics and drugs may have significant negative health impact that is not readily detectable by routine monitoring. This study assessed temperature and humidity throughout supply chains used to transport and store health commodities, such as RDTs. Methods Monitoring devices capable of recording temperature and humidity were deployed to Burkina Faso (8), Senegal (10), Ethiopia (13) and the Philippines (6) over a 13-month period. The devices travelled through government supply chains, usually alongside RDTs, to health facilities where RDTs are stored, distributed and used. The recording period spanned just over a year, in order to avoid any biases related to seasonal temperature variations. Results In the four countries, storage and transport temperatures regularly exceeded 30.0°C; maximum humidity level recorded was above 94% for the four countries. In three of the four countries, temperatures recorded at central storage facilities exceeded pharmaceutical storage standards for over 20% of the time, in another case for a majority of the time; and sometimes exceeded storage temperatures at peripheral sites. Conclusions Malaria RDTs were regularly exposed to temperatures above recommended limits for many commercially-available RDTs and other medical commodities such as drugs, but rarely exceeded the recommended storage limits for particular products in use in these countries. The results underline the need to select RDTs, and other commodities, according to expected field conditions, actively manage the environmental conditions in supply chains in tropical and sub-tropical climates. This would benefit from a re-visit of current global standards on stability of medical commodities based in tropical and sub-tropical climatic zones. PMID:23217104

Malaria rapid diagnostic test transport and storage conditions in Burkina Faso, Senegal, Ethiopia and the Philippines.

PubMed

Albertini, Audrey; Lee, Evan; Coulibaly, Sheick Oumar; Sleshi, Markos; Faye, Babacar; Mationg, Mary Lorraine; Ouedraogo, Kadi; Tsadik, Abeba G; Feleke, Sendeaw Maksha; Diallo, Ibrahima; Gaye, Oumar; Luchavez, Jennifer; Bennett, Jessica; Bell, David

2012-12-06

As more point of care diagnostics become available, the need to transport and store perishable medical commodities to remote locations increases. As with other diagnostics, malaria rapid diagnostic tests (RDTs) must be highly reliable at point of use, but exposure to adverse environmental conditions during distribution has the potential to degrade tests and accuracy. In remote locations, poor quality diagnostics and drugs may have significant negative health impact that is not readily detectable by routine monitoring. This study assessed temperature and humidity throughout supply chains used to transport and store health commodities, such as RDTs. Monitoring devices capable of recording temperature and humidity were deployed to Burkina Faso (8), Senegal (10), Ethiopia (13) and the Philippines (6) over a 13-month period. The devices travelled through government supply chains, usually alongside RDTs, to health facilities where RDTs are stored, distributed and used. The recording period spanned just over a year, in order to avoid any biases related to seasonal temperature variations. In the four countries, storage and transport temperatures regularly exceeded 30.0°C; maximum humidity level recorded was above 94% for the four countries. In three of the four countries, temperatures recorded at central storage facilities exceeded pharmaceutical storage standards for over 20% of the time, in another case for a majority of the time; and sometimes exceeded storage temperatures at peripheral sites. Malaria RDTs were regularly exposed to temperatures above recommended limits for many commercially-available RDTs and other medical commodities such as drugs, but rarely exceeded the recommended storage limits for particular products in use in these countries. The results underline the need to select RDTs, and other commodities, according to expected field conditions, actively manage the environmental conditions in supply chains in tropical and sub-tropical climates. This would benefit from a re-visit of current global standards on stability of medical commodities based in tropical and sub-tropical climatic zones.

Application of impulse oscillometry and bronchial dilation test for analysis in patients with asthma and chronic obstructive pulmonary disease

PubMed Central

Li, Yueyue; Chen, Yang; Wang, Ping

2015-01-01

Impulse oscillometry (IOS) is a good method for measuring airway resistance. The aim of this study was to assess the diagnostic contribution of IOS combined with bronchial dilation test (BDT) when distinguishing between patients with asthma and those with chronic obstructive pulmonary disease (COPD). 870 were enrolled in the study including 561 patients with asthma, 100 patients with COPD and 209 patients with chronic coughing or normal subjects. All the participants underwent routine pulmonary function tests, IOS and BDT examination. And IOS examination was before and after BDT. IOS parameters (R5, R20, R25, R35, X5, X20, X25, X35, Fres, Zrs & RP) and forced expiratory volume in one second (FEV1) were recorded. Receiver operating characteristics (ROC) curve analysis was performed to evaluate the diagnostic ability to differentiate asthma and COPD. The discriminative power of the various parameters studied was determined by means of ROC curves: the area under the curve (AUC), sensitivity and specificity. The X5, X20, X25, X35, Fres, Zrs and Rp correlated better with COPD. In particular, X5, Fres and X25 have been found to be significantly correlated with COPD. The diagnostic efficiency of X5, Fres and X25 when diagnosis COPD, expressed by ROC curve parameters, was as follows: AUC (0.725, 0.730, 0.724), sensitivity (67%, 77%, 83%) and specificity (68%, 65%, 58%), respectively. The diagnostic efficiency of Zrs, R5 and X35 when diagnosis asthma, expressed by ROC curve parameters, was as follows: AUC (0.721, 0.710, 0.695), sensitivity (62%, 72%, 53%) and specificity (72%, 61%, 76%), respectively. Our findings show, that X5, X25 and Fres may be useful for predictions and evaluations for COPD. And R5, X35 and Zrs may provide useful IOS parameters for asthma. IOS combined BDT could be useful diagnostic and differential diagnosis between asthma and COPD. PMID:25785124

Application of impulse oscillometry and bronchial dilation test for analysis in patients with asthma and chronic obstructive pulmonary disease.

PubMed

Li, Yueyue; Chen, Yang; Wang, Ping

2015-01-01

Impulse oscillometry (IOS) is a good method for measuring airway resistance. The aim of this study was to assess the diagnostic contribution of IOS combined with bronchial dilation test (BDT) when distinguishing between patients with asthma and those with chronic obstructive pulmonary disease (COPD). 870 were enrolled in the study including 561 patients with asthma, 100 patients with COPD and 209 patients with chronic coughing or normal subjects. All the participants underwent routine pulmonary function tests, IOS and BDT examination. And IOS examination was before and after BDT. IOS parameters (R5, R20, R25, R35, X5, X20, X25, X35, Fres, Zrs & RP) and forced expiratory volume in one second (FEV1) were recorded. Receiver operating characteristics (ROC) curve analysis was performed to evaluate the diagnostic ability to differentiate asthma and COPD. The discriminative power of the various parameters studied was determined by means of ROC curves: the area under the curve (AUC), sensitivity and specificity. The X5, X20, X25, X35, Fres, Zrs and Rp correlated better with COPD. In particular, X5, Fres and X25 have been found to be significantly correlated with COPD. The diagnostic efficiency of X5, Fres and X25 when diagnosis COPD, expressed by ROC curve parameters, was as follows: AUC (0.725, 0.730, 0.724), sensitivity (67%, 77%, 83%) and specificity (68%, 65%, 58%), respectively. The diagnostic efficiency of Zrs, R5 and X35 when diagnosis asthma, expressed by ROC curve parameters, was as follows: AUC (0.721, 0.710, 0.695), sensitivity (62%, 72%, 53%) and specificity (72%, 61%, 76%), respectively. Our findings show, that X5, X25 and Fres may be useful for predictions and evaluations for COPD. And R5, X35 and Zrs may provide useful IOS parameters for asthma. IOS combined BDT could be useful diagnostic and differential diagnosis between asthma and COPD.

Diagnostic and Therapeutic Advances: Distal Symmetric Polyneuropathy

PubMed Central

Callaghan, Brian C.; Price, Raymond S.; Feldman, Eva L.

2016-01-01

Importance Peripheral neuropathy is a highly prevalent and morbid condition affecting 2–7% of the population. Patients frequently suffer from pain and are at risk of falls, ulcerations, and amputations. We aimed to review recent diagnostic and therapeutic advances in peripheral neuropathy in distal symmetric polyneuropathy, the most common subtype of peripheral neuropathy. Observations and Advances Current evidence supports limited routine laboratory testing in patients with distal symmetric polyneuropathy. Patients without a known cause should have a complete blood count, comprehensive metabolic panel, B12, serum protein electrophoresis with immunofixation, fasting glucose, and a glucose tolerance test. The presence of atypical features such as asymmetry, non-length-dependence, motor predominance, acute or subacute onset, and/or prominent autonomic involvement should prompt a consultation with a neurologist or neuromuscular specialist. Electrodiagnostic tests and magnetic resonance imaging of the neuroaxis are the main drivers of the cost of the diagnostic evaluation, but evidence supporting their use is lacking. Strong evidence supports the use of tricyclic antidepressants, serotonin and norepinephrine reuptake inhibitors, and voltage-gated calcium channel ligands in the treatment of neuropathic pain. More intensive glucose control substantially reduces the incidence of distal symmetric polyneuropathy in patients with type 1 diabetes, but does not in type 2 diabetes. Conclusions and Relevance The opportunity exists to improve guideline concordant testing in distal symmetric polyneuropathy patients. Moreover, the role of electrodiagnostic tests needs to be further defined, and interventions to reduce magnetic resonance imaging use in this population are needed. Even though several efficacious medications exist for neuropathic pain treatment, pain is still under-recognized and undertreated. New disease modifying medications are needed to prevent and treat peripheral neuropathy, particularly in type 2 diabetes. PMID:26599185

Practical mental health assessment in primary care. Validity and utility of the Quick PsychoDiagnostics Panel.

PubMed

Shedler, J; Beck, A; Bensen, S

2000-07-01

Many case-finding instruments are available to help primary care physicians (PCPs) diagnose depression, but they are not widely used. Physicians often consider these instruments too time consuming or feel they do not provide sufficient diagnostic information. Our study examined the validity and utility of the Quick PsychoDiagnostics (QPD) Panel, an automated mental health test designed to meet the special needs of PCPs. The test screens for 9 common psychiatric disorders and requires no physician time to administer or score. We evaluated criterion validity relative to the Structured Clinical Interview for DSM-IV (SCID), and evaluated convergent validity by correlating QPD Panel scores with established mental health measures. Sensitivity to change was examined by readministering the test to patients pretreatment and posttreatment. Utility was evaluated through physician and patient satisfaction surveys. For major depression, sensitivity and specificity were 81% and 96%, respectively. For other disorders, sensitivities ranged from 69% to 98%, and specificities ranged from 90% to 97%. The depression severity score correlated highly with the Beck, Hamilton, Zung, and CES-D depression scales, and the anxiety score correlated highly with the Spielberger State-Trait Anxiety Inventory and the anxiety subscale of the Symptom Checklist 90 (Ps <.001). The test was sensitive to change. All PCPs agreed or strongly agreed that the QPD Panel "is convenient and easy to use," "can be used immediately by any physician," and "helps provide better patient care." Patients also rated the test favorably. The QPD Panel is a valid mental health assessment tool that can diagnose a range of common psychiatric disorders and is practical for routine use in primary care.

An EEG should not be obtained routinely after first unprovoked seizure in childhood.

PubMed

Gilbert, D L; Buncher, C R

2000-02-08

To quantify and analyze the value of expected information from an EEG after first unprovoked seizure in childhood. An EEG is often recommended as part of the standard diagnostic evaluation after first seizure. A MEDLINE search from 1980 to 1998 was performed. From eligible studies, data on EEG results and seizure recurrence risk in children were abstracted, and sensitivity, specificity, and positive and negative predictive values of EEG in predicting recurrence were calculated. Linear information theory was used to quantify and compare the expected information from the EEG in all studies. Standard test-treat decision analysis with a treatment threshold at 80% recurrence risk was used to determine the range of pretest recurrence probabilities over which testing affects treatment decisions. Four studies involving 831 children were eligible for analysis. At best, the EEG had a sensitivity of 61%, a specificity of 71%, and an expected information of 0.16 out of a possible 0.50. The pretest probability of recurrence was less than the lower limit of the range for rational testing in all studies. In this analysis, the quantity of expected information from the EEG was too low to affect treatment recommendations in most patients. EEG should be ordered selectively, not routinely, after first unprovoked seizure in childhood.

Radiation dose reduction with the adaptive statistical iterative reconstruction (ASIR) technique for chest CT in children: an intra-individual comparison.

PubMed

Lee, Seung Hyun; Kim, Myung-Joon; Yoon, Choon-Sik; Lee, Mi-Jung

2012-09-01

To retrospectively compare radiation dose and image quality of pediatric chest CT using a routine dose protocol reconstructed with filtered back projection (FBP) (the Routine study) and a low-dose protocol with 50% adaptive statistical iterative reconstruction (ASIR) (the ASIR study). We retrospectively reviewed chest CT performed in pediatric patients who underwent both the Routine study and the ASIR study on different days between January 2010 and August 2011. Volume CT dose indices (CTDIvol), dose length products (DLP), and effective doses were obtained to estimate radiation dose. The image quality was evaluated objectively as noise measured in the descending aorta and paraspinal muscle, and subjectively by three radiologists for noise, sharpness, artifacts, and diagnostic acceptability using a four-point scale. The paired Student's t-test and the Wilcoxon signed-rank test were used for statistical analysis. Twenty-six patients (M:F=13:13, mean age 11.7) were enrolled. The ASIR studies showed 60.3%, 56.2%, and 55.2% reductions in CTDIvol (from 18.73 to 7.43 mGy, P<0.001), DLP (from 307.42 to 134.51 mGy×cm, P<0.001), and effective dose (from 4.12 to 1.84 mSv, P<0.001), respectively, compared with the Routine studies. The objective noise was higher in the paraspinal muscle of the ASIR studies (20.81 vs. 16.67, P=0.004), but was not different in the aorta (18.23 vs. 18.72, P=0.726). The subjective image quality demonstrated no difference between the two studies. A low-dose protocol with 50% ASIR allows radiation dose reduction in pediatric chest CT by more than 55% while maintaining image quality. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Diagnostic Methods for Platelet Bacteria Screening: Current Status and Developments

PubMed Central

Störmer, Melanie; Vollmer, Tanja

2014-01-01

Summary Bacterial contamination of blood components and the prevention of transfusion-associated bacterial infection still remains a major challenge in transfusion medicine. Over the past few decades, a significant reduction in the transmission of viral infections has been achieved due to the introduction of mandatory virus screening. Platelet concentrates (PCs) represent one of the highest risks for bacterial infection. This is due to the required storage conditions for PCs in gas-permeable containers at room temperature with constant agitation, which support bacterial proliferation from low contamination levels to high titers. In contrast to virus screening, since 1997 in Germany bacterial testing of PCs is only performed as a routine quality control or, since 2008, to prolong the shelf life to 5 days. In general, bacterial screening of PCs by cultivation methods is implemented by the various blood services. Although these culturing systems will remain the gold standard, the significance of rapid methods for screening for bacterial contamination has increased over the last few years. These new methods provide powerful tools for increasing the bacterial safety of blood components. This article summarizes the course of policies and provisions introduced to increase bacterial safety of blood components in Germany. Furthermore, we give an overview of the different diagnostic methods for bacterial screening of PCs and their current applicability in routine screening processes. PMID:24659944

The role of human papillomavirus in screening for cervical cancer.

PubMed

McFadden, S E; Schumann, L

2001-03-01

To review the options for effectively screening for cervical cancer, including human papilloma virus (HPV) identification, cytologic screening, colposcopy, or a combination approach. Current pathophysiology, diagnostic criteria, treatment approaches, and patient preparation and education related to cervical cancer screening and prevention are also included. Comprehensive review of current literature, including research and review articles. Because the Papanicolau (Pap) smear is a screening tool, not a diagnostic tool, further studies must be done to identify the actual nature of discovered abnormalities. Of particular concern is the classification of atypical squamous cells of undetermined significance (ASCUS), which may simply indicate inflammation, or may be the first indicator of serious pathology. Following ASCUS Pap smears with HPV screening will allow for a clarification of the best approach to treatment. A screening algorithm supported by a review of the literature is proposed. Cervical cancer is a preventable disease caused by certain forms of HPV. Current screening protocols are based on the use of the Pap smear; and in areas where this test is routine and available, morbidity and mortality rates have dropped dramatically. Many women throughout the world and in underserved regions of the U. S. do not have adequate access to routine screening with Pap smear technology. As long as women continue to die needlessly of cervical cancer, more comprehensive and accessible screening methods must be explored. (Cutting the unnecessary worldwide and in the U. S.).

Collection fluid helps preservation in voided urine cytology.

PubMed

Raistrick, J; Shambayati, B; Dunsmuir, W

2008-04-01

Degenerative change caused by delay in processing contributes to false-negative and false-positive diagnosis of urothelial carcinoma in cytology. The aim of the study was to see if the use of a collection fluid for urine samples made a significant difference to urine cytology diagnosis, and if one was better suited for routine use in the hospital laboratory. Three cell collection fluids were evaluated by analysing the preservation and degeneration of cells in urine samples, as was the routine preparation which did not use a collection fluid. In the design study 50 voided urine specimens were taken at random from the hospital haematuria clinic. Three commercially available collection fluids cytolyt, cytospin and cytoRich Blue and the hospital's routine conventional preparation of urine were compared. The degree of degeneration, and so preservation, was assessed by a table of chosen criteria; then ranked and analysed by Friedman's nonparametric test, at P = 0.05. A second table showing the cell content of each slide was also made. These showed no significant diagnostic difference between the collection fluids, but there was a significant difference between the collection fluids and the routine preparation. Minor differences that do not affect diagnosis, such as crystals and ghost red blood cells, were noted in cytospin and cytoRich Blue. It is recommended that a collection fluid is used. This choice should be made after health and safety issues and cost are considered.

Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Combined Species Identification and Drug Sensitivity Testing in Mycobacteria.

PubMed

Ceyssens, Pieter-Jan; Soetaert, Karine; Timke, Markus; Van den Bossche, An; Sparbier, Katrin; De Cremer, Koen; Kostrzewa, Markus; Hendrickx, Marijke; Mathys, Vanessa

2017-02-01

Species identification and drug susceptibility testing (DST) of mycobacteria are important yet complex processes traditionally reserved for reference laboratories. Recent technical improvements in matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has started to facilitate routine mycobacterial identifications in clinical laboratories. In this paper, we investigate the possibility of performing phenotypic MALDI-based DST in mycobacteriology using the recently described MALDI Biotyper antibiotic susceptibility test rapid assay (MBT-ASTRA). We randomly selected 72 clinical Mycobacterium tuberculosis and nontuberculous mycobacterial (NTM) strains, subjected them to MBT-ASTRA methodology, and compared its results to current gold-standard methods. Drug susceptibility was tested for rifampin, isoniazid, linezolid, and ethambutol (M. tuberculosis, n = 39), and clarithromycin and rifabutin (NTM, n = 33). Combined species identification was performed using the Biotyper Mycobacteria Library 4.0. Mycobacterium-specific MBT-ASTRA parameters were derived (calculation window, m/z 5,000 to 13,000, area under the curve [AUC] of >0.015, relative growth [RG] of <0.5; see the text for details). Using these settings, MBT-ASTRA analyses returned 175/177 M. tuberculosis and 65/66 NTM drug resistance profiles which corresponded to standard testing results. Turnaround times were not significantly different in M. tuberculosis testing, but the MBT-ASTRA method delivered on average a week faster than routine DST in NTM. Databases searches returned 90.4% correct species-level identifications, which increased to 98.6% when score thresholds were lowered to 1.65. In conclusion, the MBT-ASTRA technology holds promise to facilitate and fasten mycobacterial DST and to combine it directly with high-confidence species-level identifications. Given the ease of interpretation, its application in NTM typing might be the first in finding its way to current diagnostic workflows. However, further validations and automation are required before routine implementation can be envisioned. Copyright © 2017 American Society for Microbiology.

Diagnostic Assessment of Deep Learning Algorithms for Detection of Lymph Node Metastases in Women With Breast Cancer.

PubMed

Ehteshami Bejnordi, Babak; Veta, Mitko; Johannes van Diest, Paul; van Ginneken, Bram; Karssemeijer, Nico; Litjens, Geert; van der Laak, Jeroen A W M; Hermsen, Meyke; Manson, Quirine F; Balkenhol, Maschenka; Geessink, Oscar; Stathonikos, Nikolaos; van Dijk, Marcory Crf; Bult, Peter; Beca, Francisco; Beck, Andrew H; Wang, Dayong; Khosla, Aditya; Gargeya, Rishab; Irshad, Humayun; Zhong, Aoxiao; Dou, Qi; Li, Quanzheng; Chen, Hao; Lin, Huang-Jing; Heng, Pheng-Ann; Haß, Christian; Bruni, Elia; Wong, Quincy; Halici, Ugur; Öner, Mustafa Ümit; Cetin-Atalay, Rengul; Berseth, Matt; Khvatkov, Vitali; Vylegzhanin, Alexei; Kraus, Oren; Shaban, Muhammad; Rajpoot, Nasir; Awan, Ruqayya; Sirinukunwattana, Korsuk; Qaiser, Talha; Tsang, Yee-Wah; Tellez, David; Annuscheit, Jonas; Hufnagl, Peter; Valkonen, Mira; Kartasalo, Kimmo; Latonen, Leena; Ruusuvuori, Pekka; Liimatainen, Kaisa; Albarqouni, Shadi; Mungal, Bharti; George, Ami; Demirci, Stefanie; Navab, Nassir; Watanabe, Seiryo; Seno, Shigeto; Takenaka, Yoichi; Matsuda, Hideo; Ahmady Phoulady, Hady; Kovalev, Vassili; Kalinovsky, Alexander; Liauchuk, Vitali; Bueno, Gloria; Fernandez-Carrobles, M Milagro; Serrano, Ismael; Deniz, Oscar; Racoceanu, Daniel; Venâncio, Rui

2017-12-12

Application of deep learning algorithms to whole-slide pathology images can potentially improve diagnostic accuracy and efficiency. Assess the performance of automated deep learning algorithms at detecting metastases in hematoxylin and eosin-stained tissue sections of lymph nodes of women with breast cancer and compare it with pathologists' diagnoses in a diagnostic setting. Researcher challenge competition (CAMELYON16) to develop automated solutions for detecting lymph node metastases (November 2015-November 2016). A training data set of whole-slide images from 2 centers in the Netherlands with (n = 110) and without (n = 160) nodal metastases verified by immunohistochemical staining were provided to challenge participants to build algorithms. Algorithm performance was evaluated in an independent test set of 129 whole-slide images (49 with and 80 without metastases). The same test set of corresponding glass slides was also evaluated by a panel of 11 pathologists with time constraint (WTC) from the Netherlands to ascertain likelihood of nodal metastases for each slide in a flexible 2-hour session, simulating routine pathology workflow, and by 1 pathologist without time constraint (WOTC). Deep learning algorithms submitted as part of a challenge competition or pathologist interpretation. The presence of specific metastatic foci and the absence vs presence of lymph node metastasis in a slide or image using receiver operating characteristic curve analysis. The 11 pathologists participating in the simulation exercise rated their diagnostic confidence as definitely normal, probably normal, equivocal, probably tumor, or definitely tumor. The area under the receiver operating characteristic curve (AUC) for the algorithms ranged from 0.556 to 0.994. The top-performing algorithm achieved a lesion-level, true-positive fraction comparable with that of the pathologist WOTC (72.4% [95% CI, 64.3%-80.4%]) at a mean of 0.0125 false-positives per normal whole-slide image. For the whole-slide image classification task, the best algorithm (AUC, 0.994 [95% CI, 0.983-0.999]) performed significantly better than the pathologists WTC in a diagnostic simulation (mean AUC, 0.810 [range, 0.738-0.884]; P < .001). The top 5 algorithms had a mean AUC that was comparable with the pathologist interpreting the slides in the absence of time constraints (mean AUC, 0.960 [range, 0.923-0.994] for the top 5 algorithms vs 0.966 [95% CI, 0.927-0.998] for the pathologist WOTC). In the setting of a challenge competition, some deep learning algorithms achieved better diagnostic performance than a panel of 11 pathologists participating in a simulation exercise designed to mimic routine pathology workflow; algorithm performance was comparable with an expert pathologist interpreting whole-slide images without time constraints. Whether this approach has clinical utility will require evaluation in a clinical setting.

Development and Validation of a Laboratory-Developed Multiplex Real-Time PCR Assay on the BD Max System for Detection of Herpes Simplex Virus and Varicella-Zoster Virus DNA in Various Clinical Specimens.

PubMed

Pillet, Sylvie; Verhoeven, Paul O; Epercieux, Amélie; Bourlet, Thomas; Pozzetto, Bruno

2015-06-01

A multiplex real-time PCR (quantitative PCR [qPCR]) assay detecting herpes simplex virus (HSV) and varicella-zoster virus (VZV) DNA together with an internal control was developed on the BD Max platform combining automated DNA extraction and an open amplification procedure. Its performance was compared to those of PCR assays routinely used in the laboratory, namely, a laboratory-developed test for HSV DNA on the LightCycler instrument and a test using a commercial master mix for VZV DNA on the ABI7500fast system. Using a pool of negative cerebrospinal fluid (CSF) samples spiked with either calibrated controls for HSV-1 and VZV or dilutions of a clinical strain that was previously quantified for HSV-2, the empirical limit of detection of the BD Max assay was 195.65, 91.80, and 414.07 copies/ml for HSV-1, HSV-2, and VZV, respectively. All the samples from HSV and VZV DNA quality control panels (Quality Control for Molecular Diagnostics [QCMD], 2013, Glasgow, United Kingdom) were correctly identified by the BD Max assay. From 180 clinical specimens of various origins, 2 CSF samples were found invalid by the BD Max assay due to the absence of detection of the internal control; a concordance of 100% was observed between the BD Max assay and the corresponding routine tests. The BD Max assay detected the PCR signal 3 to 4 cycles earlier than did the routine methods. With results available within 2 h on a wide range of specimens, this sensitive and fully automated PCR assay exhibited the qualities required for detecting simultaneously HSV and VZV DNA on a routine basis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Six consecutive false positive cases from cell-free fetal DNA testing in a single referring centre

PubMed Central

Dugo, Nella; Padula, Francesco; Mobili, Luisa; Brizzi, Cristiana; D’Emidio, Laura; Cignini, Pietro; Mesoraca, Alvaro; Bizzoco, Domenico; Cima, Antonella; Giorlandino, Claudio

2014-01-01

Introduction recent studies have proposed the introduction of cell-free fetal DNA testing (NIPT-Non Invasive Prenatal Testing) in routine clinical practice emphasizing its high sensibility and specificity. In any case, false positive and false negative findings may result from placental mosaicism, because cell-free fetal DNA originates mainly from placenta. Case we report six cases of women who underwent chorionic villus sampling (CVS) or amniocentesis to confirm the results from NIPT: two Turner syndromes, two Triple X, one Patau syndrome, one Edward syndrome. Results using classic cytogenetic analysis and, also, Array - Comparative Genomic Hybridization (Array CGH) the karyotype of all 5 fetuses was found to be normal. Conclusion results from NIPT must always be confirmed by invasive prenatal diagnosis. It is mandatory to inform the patient that the CVS and amniocentesis still represent the only form of prenatal diagnostic test available. PMID:25332757

Rapid Detection of Prunus Necrotic Ringspot Virus by Reverse Transcription-cross-priming Amplification Coupled with Nucleic Acid Test Strip Cassette.

PubMed

Huo, Ya-Yun; Li, Gui-Fen; Qiu, Yan-Hong; Li, Wei-Min; Zhang, Yong-Jiang

2017-11-23

Prunus necrotic ringspot virus (PNRSV) is one of the most devastating viruses to Prunus spp. In this study, we developed a diagnostic system RT-CPA-NATSC, wherein reverse transcription-cross-priming amplification (RT-CPA) is coupled with nucleic acid test strip cassette (NATSC), a vertical flow (VF) visualization, for PNRSV detection. The RT-CPA-NATSC assay targets the encoding gene of the PNRSV coat protein with a limit of detection of 72 copies per reaction and no cross-reaction with the known Prunus pathogenic viruses and viroids, demonstrating high sensitivity and specificity. The reaction is performed on 60 °C and can be completed less than 90 min with the prepared template RNA. Field sample test confirmed the reliability of RT-CPA-NATSC, indicating the potential application of this simple and rapid detection method in routine test of PNRSV.

Integration and acceleration of virtual microscopy as the key to successful implementation into the routine diagnostic process.

PubMed

Wienert, Stephan; Beil, Michael; Saeger, Kai; Hufnagl, Peter; Schrader, Thomas

2009-01-09

The virtual microscopy is widely accepted in Pathology for educational purposes and teleconsultation but is far from the routine use in surgical pathology due to the technical requirements and some limitations. A technical problem is the limited bandwidth of a usual network and the delayed transmission rate and presentation time on the screen. In this study the process of secondary diagnostic was evaluated using the "T.Konsult Pathologie" service of the Professional Association of German Pathologists within the German breast cancer screening program. The characteristics of the access to the WSI (Whole Slide Images) have been analyzed to explore the possibilities of prefetching and caching to reduce the presentation and transfer time with the goal to increase user acceptance. The log files of the web server were analyzed to reconstruct the movements of the pathologist on the WSI and to create the observation path. Using a specialized tool the observation paths were extracted automatically from the log files. The attributes linearity, 3-point-linearity, changes per request, and number of consecutive requests were calculated to design, develop and evaluate different caching and prefetching strategies. The analysis of the observation paths showed that a complete accordance of two image requests is a very rare event. But more frequently a partial covering of two requested image areas can be found. In total 257 diagnostic paths from 131 WSI have been extracted and analysed. On average a diagnostic path consists of 16 image requests and takes 189 seconds between first and last image request. The mean linearity was 0,41 and the mean 3-point-linearity 0,85. Three different caching algorithms have been compared with respect to hit rate and additional image requests on the WSI server. Tests demonstrated that 95% of the diagnostic paths could be loaded without any deletion of entries in the cache (cache size 12,2 Megapixel). If the image parts are stored after JPEG compression this complies with less than 2 MB. WSI telepathology is a technology which offers the possibility to break the limitations of conventional static telepathology. The complete histological slide may be investigated instead of sets of images of lesions sampled by the presenting pathologist. The benefit is demonstrated by the high diagnostic security of 95% accordance between first and second diagnosis.

Integration and acceleration of virtual microscopy as the key to successful implementation into the routine diagnostic process

PubMed Central

Wienert, Stephan; Beil, Michael; Saeger, Kai; Hufnagl, Peter; Schrader, Thomas

2009-01-01

Background The virtual microscopy is widely accepted in Pathology for educational purposes and teleconsultation but is far from the routine use in surgical pathology due to the technical requirements and some limitations. A technical problem is the limited bandwidth of a usual network and the delayed transmission rate and presentation time on the screen. Methods In this study the process of secondary diagnostic was evaluated using the "T.Konsult Pathologie" service of the Professional Association of German Pathologists within the German breast cancer screening program. The characteristics of the access to the WSI (Whole Slide Images) have been analyzed to explore the possibilities of prefetching and caching to reduce the presentation and transfer time with the goal to increase user acceptance. The log files of the web server were analyzed to reconstruct the movements of the pathologist on the WSI and to create the observation path. Using a specialized tool the observation paths were extracted automatically from the log files. The attributes linearity, 3-point-linearity, changes per request, and number of consecutive requests were calculated to design, develop and evaluate different caching and prefetching strategies. Results The analysis of the observation paths showed that a complete accordance of two image requests is a very rare event. But more frequently a partial covering of two requested image areas can be found. In total 257 diagnostic paths from 131 WSI have been extracted and analysed. On average a diagnostic path consists of 16 image requests and takes 189 seconds between first and last image request. The mean linearity was 0,41 and the mean 3-point-linearity 0,85. Three different caching algorithms have been compared with respect to hit rate and additional image requests on the WSI server. Tests demonstrated that 95% of the diagnostic paths could be loaded without any deletion of entries in the cache (cache size 12,2 Megapixel). If the image parts are stored after JPEG compression this complies with less than 2 MB. Discussion WSI telepathology is a technology which offers the possibility to break the limitations of conventional static telepathology. The complete histological slide may be investigated instead of sets of images of lesions sampled by the presenting pathologist. The benefit is demonstrated by the high diagnostic security of 95% accordance between first and second diagnosis. PMID:19134181

Flexible Lab-Tailored Cut-Offs for Suitability of Formalin-Fixed Tumor Samples for Diagnostic Mutational Analyses

PubMed Central

Mariani, Sara; Tondat, Fabrizio; Pacchioni, Donatella; Molinaro, Luca; Barreca, Antonella; Macrì, Luigia; Chiusa, Luigi; di Celle, Paola Francia; Cassoni, Paola; Sapino, Anna

2015-01-01

The selection of proper tissues from formalin-fixed and paraffin-embedded tumors before diagnostic molecular testing is responsibility of the pathologist and represents a crucial step to produce reliable test results. The international guidelines suggest two cut-offs, one for the percentage and one for the number of tumor cells, in order to enrich the tumor content before DNA extraction. The aim of the present work was two-fold: to evaluate to what extent a low percentage or absolute number of tumor cells can be qualified for somatic mutation testing; and to determine how assay sensitivities can guide pathologists towards a better definition of morphology-based adequacy cut-offs. We tested 1797 tumor specimens from melanomas, colorectal and lung adenocarcinomas. Respectively, their BRAF, K-RAS and EGFR genes were analyzed at specific exons by mutation-enriched PCR, pyrosequencing, direct sequencing and real-time PCR methods. We demonstrate that poorly cellular specimens do not modify the frequency distribution of either mutated or wild-type DNA samples nor that of specific mutations. This observation suggests that currently recommended cut-offs for adequacy of specimens to be processed for molecular assays seem to be too much stringent in a laboratory context that performs highly sensitive routine analytical methods. In conclusion, new cut-offs are needed based on test sensitivities and documented tumor heterogeneity. PMID:25844806

Diagnostic performance of alpha-fetoprotein, lens culinaris agglutinin-reactive alpha-fetoprotein, des-gamma carboxyprothrombin, and glypican-3 for the detection of hepatocellular carcinoma: a systematic review and meta-analysis protocol

PubMed Central

2013-01-01

Background Diagnosis of early-stage hepatocellular carcinoma (HCC) followed by curative resection or liver transplantation offers the best chance for long-term patient survival. Clinically, ultrasonography has suboptimal sensitivity for detecting early-stage HCC. Several serological tests including alpha-fetoprotein (AFP), the ratio of lens culinaris agglutinin-reactive alpha-fetoprotein to total AFP (AFP-L3/AFP), des-gamma carboxyprothrombin (DCP), and glypican-3 (GPC-3) have been widely investigated as diagnostic biomarkers for early-stage HCC in at-risk populations. However, these tests are not recommended for routine HCC screening. Our objective is to determine the diagnostic performance of AFP, AFP-L3/AFP, DCP, and GPC-3 for the detection of HCC, particularly early-stage tumors meeting the Milan criteria. Methods/design We will include cross-sectional studies that consecutively or randomly recruit target populations. We will search the Cochrane Library, Medline, Embase, Science Citation Index, and the Chinese National Knowledge Infrastructure. We will also search the MEDION and ARIF databases to identify diagnostic systematic reviews that include primary studies. Reference lists of relevant reviews will be searched for additional trials. Language restrictions will not be applied. Two reviewers will independently screen study eligibility and extract data. Methodological quality will be assessed according to the revised tool for the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). Two authors will apply the QUADAS-2 assessment to all the included studies, and any discrepancies will be resolved by the third author. The following test characteristics will be extracted into 2 × 2 tables for all included studies: true positives, false positives, true negatives, and false negatives. Study-specific estimates of sensitivity and specificity with 95% confidence intervals will be displayed in forest plots. When possible, we will use the bivariate random-effects model or the Rutter and Gatsonis hierarchical summary receiver operating characteristic model for statistical analysis. To investigate heterogeneity, we will include study designs, population characteristics, test characteristics, and types of reference standard as the study-level variables. Discussion Our systematic review will allow patients, clinicians, and researchers to determine the diagnostic performance of AFP, AFP-L3/AFP, DCP, and GPC-3 for the detection of early-stage HCC and the potential roles of these diagnostic biomarkers in the existing diagnostic pathways. Systematic Review Registration: PROSPERO 2013; CRD42013003879 PMID:23738605

A new generation of cancer genome diagnostics for routine clinical use: overcoming the roadblocks to personalized cancer medicine.

PubMed

Heuckmann, J M; Thomas, R K

2015-09-01

The identification of 'druggable' kinase gene alterations has revolutionized cancer treatment in the last decade by providing new and successfully targetable drug targets. Thus, genotyping tumors for matching the right patients with the right drugs have become a clinical routine. Today, advances in sequencing technology and computational genome analyses enable the discovery of a constantly growing number of genome alterations relevant for clinical decision making. As a consequence, several technological approaches have emerged in order to deal with these rapidly increasing demands for clinical cancer genome analyses. Here, we describe challenges on the path to the broad introduction of diagnostic cancer genome analyses and the technologies that can be applied to overcome them. We define three generations of molecular diagnostics that are in clinical use. The latest generation of these approaches involves deep and thus, highly sensitive sequencing of all therapeutically relevant types of genome alterations-mutations, copy number alterations and rearrangements/fusions-in a single assay. Such approaches therefore have substantial advantages (less time and less tissue required) over PCR-based methods that typically have to be combined with fluorescence in situ hybridization for detection of gene amplifications and fusions. Since these new technologies work reliably on routine diagnostic formalin-fixed, paraffin-embedded specimens, they can help expedite the broad introduction of personalized cancer therapy into the clinic by providing comprehensive, sensitive and accurate cancer genome diagnoses in 'real-time'. © The Author 2015. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

MOON-test - determination of motor performance in the pediatric oncology.

PubMed

Götte, M; Kesting, S; Albrecht, C; Worth, A; Bös, K; Boos, J

2013-05-01

Pediatric cancer patients suffer from various negative consequences due to the disease, the medical therapy and the inactivity during the intensive treatment. Only few studies have systematically identified the adverse effects of cancer on motor performance in childhood. To determine the motor performance of pediatric cancer patients, a motor performance test was developed which is applicable for this specific patient group. Eight test items with reference values for healthy children were merged to the MOON-test (test for motor performance in the oncology). MOON was tested for feasibility and acceptance in 33 patients aged 4-18 years. Feasibility was confirmed for children with different types of cancer (hematological malignancies and solid tumors) and with amputation, endoprosthesis, during aplasia as well as reduced general condition. Furthermore the patients showed a broad acceptance. Based on the study findings, the use of MOON-test as a standardized motor performance diagnostic tool in clinical routine of oncological acute clinics as well as rehabilitation clinics can be recommended.· © Georg Thieme Verlag KG Stuttgart · New York.

Dual-Routine HCV/HIV Testing: Seroprevalence and Linkage to Care in Four Community Health Centers in Philadelphia, Pennsylvania.

PubMed

Coyle, Catelyn; Kwakwa, Helena

2016-01-01

Despite common risk factors, screening for hepatitis C virus (HCV) and HIV at the same time as part of routine medical care (dual-routine HCV/HIV testing) is not commonly implemented in the United States. This study examined improvements in feasibility of implementation, screening increase, and linkage to care when a dual-routine HCV/HIV testing model was integrated into routine primary care. National Nursing Centers Consortium implemented a dual-routine HCV/HIV testing model at four community health centers in Philadelphia, Pennsylvania, on September 1, 2013. Routine HCV and opt-out HIV testing replaced the routine HCV and opt-in HIV testing model through medical assistant-led, laboratory-based testing and electronic medical record modification to prompt, track, report, and facilitate reimbursement for tests performed on uninsured individuals. This study examined testing, seropositivity, and linkage-to-care comparison data for the nine months before (December 1, 2012-August 31, 2013) and after (September 1, 2013-May 31, 2014) implementation of the dual-routine HCV/HIV testing model. A total of 1,526 HCV and 1,731 HIV tests were performed before, and 1,888 HCV and 3,890 HIV tests were performed after dual-routine testing implementation, resulting in a 23.7% increase in HCV tests and a 124.7% increase in HIV tests. A total of 70 currently HCV-infected and four new HIV-seropositive patients vs. 101 HCV-infected and 13 new HIV-seropositive patients were identified during these two periods, representing increases of 44.3% for HCV antibody-positive and RNA-positive tests and 225.0% for HIV-positive tests. Linkage to care increased from 27 currently infected HCV--positive and one HIV-positive patient pre-dual-routine testing to 39 HCV--positive and nine HIV-positive patients post-dual-routine testing. The dual-routine HCV/HIV testing model shows that integrating dual-routine testing in a primary care setting is possible and leads to increased HCV and HIV screening, enhanced seropositivity diagnosis, and improved linkage to care.

Dual-Routine HCV/HIV Testing: Seroprevalence and Linkage to Care in Four Community Health Centers in Philadelphia, Pennsylvania

PubMed Central

Kwakwa, Helena

2016-01-01

Objective Despite common risk factors, screening for hepatitis C virus (HCV) and HIV at the same time as part of routine medical care (dual-routine HCV/HIV testing) is not commonly implemented in the United States. This study examined improvements in feasibility of implementation, screening increase, and linkage to care when a dual-routine HCV/HIV testing model was integrated into routine primary care. Methods National Nursing Centers Consortium implemented a dual-routine HCV/HIV testing model at four community health centers in Philadelphia, Pennsylvania, on September 1, 2013. Routine HCV and opt-out HIV testing replaced the routine HCV and opt-in HIV testing model through medical assistant-led, laboratory-based testing and electronic medical record modification to prompt, track, report, and facilitate reimbursement for tests performed on uninsured individuals. This study examined testing, seropositivity, and linkage-to-care comparison data for the nine months before (December 1, 2012–August 31, 2013) and after (September 1, 2013–May 31, 2014) implementation of the dual-routine HCV/HIV testing model. Results A total of 1,526 HCV and 1,731 HIV tests were performed before, and 1,888 HCV and 3,890 HIV tests were performed after dual-routine testing implementation, resulting in a 23.7% increase in HCV tests and a 124.7% increase in HIV tests. A total of 70 currently HCV-infected and four new HIV-seropositive patients vs. 101 HCV-infected and 13 new HIV-seropositive patients were identified during these two periods, representing increases of 44.3% for HCV antibody-positive and RNA-positive tests and 225.0% for HIV-positive tests. Linkage to care increased from 27 currently infected HCV--positive and one HIV-positive patient pre-dual-routine testing to 39 HCV--positive and nine HIV-positive patients post-dual-routine testing. Conclusion The dual-routine HCV/HIV testing model shows that integrating dual-routine testing in a primary care setting is possible and leads to increased HCV and HIV screening, enhanced seropositivity diagnosis, and improved linkage to care. PMID:26862229

New diagnostics for melanoma detection: from artificial intelligence to RNA microarrays.

PubMed

Ahlgrimm-Siess, Verena; Laimer, Martin; Arzberger, Edith; Hofmann-Wellenhof, Rainer

2012-07-01

Early detection of melanoma remains crucial to ensuring a favorable prognosis. Dermoscopy and total body photography are well-established noninvasive aids that increase the diagnostic accuracy of dermatologists in their daily routine, beyond that of a naked-eye examination. New noninvasive diagnostic techniques, such as reflectance confocal microscopy, multispectral digital imaging and RNA microarrays, are currently being investigated to determine their utility for melanoma detection. This review presents emerging technologies for noninvasive melanoma diagnosis, and discusses their advantages and limitations.

Clinical criteria for psychiatric diagnosis and DSM-III.

PubMed

Spitzer, R L; Endicott, J; Robins, E

1975-11-01

The authors identify the differences in formal inclusion and exclusion criteria used to classify patient data into diagnoses as the largest source of diagnostic unreliability in psychiatry. They describe the efforts that have been made to reduce these differences, particularly the specified criteria approach to defining diagnostic categories, which was developed for research purposes. On the basis of studies showing that the use of specified criteria increases the reliability of diagnostic judgments, they suggest that including such criteria in the next edition of APA's Diagnostic and Statistical Manual of Mental Disorders (DSM-III) would improve the reliability and validity of routine psychiatric diagnosis.

Diagnostic tests and algorithms used in the investigation of haematuria: systematic reviews and economic evaluation.

PubMed

Rodgers, M; Nixon, J; Hempel, S; Aho, T; Kelly, J; Neal, D; Duffy, S; Ritchie, G; Kleijnen, J; Westwood, M

2006-06-01

To determine the most effective diagnostic strategy for the investigation of microscopic and macroscopic haematuria in adults. Electronic databases from inception to October 2003, updated in August 2004. A systematic review was undertaken according to published guidelines. Decision analytic modelling was undertaken, based on the findings of the review, expert opinion and additional information from the literature, to assess the relative cost-effectiveness of plausible alternative tests that are part of diagnostic algorithms for haematuria. A total of 118 studies met the inclusion criteria. No studies that evaluated the effectiveness of diagnostic algorithms for haematuria or the effectiveness of screening for haematuria or investigating its underlying cause were identified. Eighteen out of 19 identified studies evaluated dipstick tests and data from these suggested that these are moderately useful in establishing the presence of, but cannot be used to rule out, haematuria. Six studies using haematuria as a test for the presence of a disease indicated that the detection of microhaematuria cannot alone be considered a useful test either to rule in or rule out the presence of a significant underlying pathology (urinary calculi or bladder cancer). Forty-eight of 80 studies addressed methods to localise the source of bleeding (renal or lower urinary tract). The methods and thresholds described in these studies varied greatly, precluding any estimate of a 'best performance' threshold that could be applied across patient groups. However, studies of red blood cell morphology that used a cut-off value of 80% dysmorphic cells for glomerular disease reported consistently high specificities (potentially useful in ruling in a renal cause for haematuria). The reported sensitivities were generally low. Twenty-eight studies included data on the accuracy of laboratory tests (tumour markers, cytology) for the diagnosis of bladder cancer. The majority of tumour marker studies evaluated nuclear matrix protein 22 or bladder tumour antigen. The sensitivity and specificity ranges suggested that neither of these would be useful either for diagnosing bladder cancer or for ruling out patients for further investigation (cystoscopy). However, the evidence remains sparse and the diagnostic accuracy estimates varied widely between studies. Fifteen studies evaluating urine cytology as a test for urinary tract malignancies were heterogeneous and poorly reported. The calculated specificity values were generally high, suggesting some possible utility in confirming malignancy. However, the evidence suggests that urine cytology has no application in ruling out malignancy or excluding patients from further investigation. Fifteen studies evaluated imaging techniques [computed tomography (CT), intravenous urography (IVU) or ultrasound scanning (US)] to detect the underlying cause of haematuria. The target condition and the reference standard varied greatly between these studies. The diagnostic accuracy data for several individual studies appeared promising but meaningful comparison of the available imaging technologies was impossible. Eight studies met the inclusion criteria but addressed different parts of the diagnostic chain (e.g. screening programmes, laboratory investigations, full urological work-up). No single study addressed the complete diagnostic process. The review also highlighted a number of methodological limitations of these studies, including their lack of generalisability to the UK context. Separate decision analytic models were therefore developed to progress estimation of the optimal strategy for the diagnostic management of haematuria. The economic model for the detection of microhaematuria found that immediate microscopy following a positive dipstick test would improve diagnostic efficiency as it eliminates the high number of false positives produced by dipstick testing. Strategies that use routine microscopy may be associated with high numbers of false results, but evidence was lacking regarding the accuracy of routine microscopy and estimates were adopted for the model. The model for imaging the upper urinary tract showed that US detects more tumours than IVU at one-third of the cost, and is also associated with fewer false results. For any cause of haematuria, CT was shown to have a mean incremental cost-effectiveness ratio of pounds sterling 9939 in comparison with the next best option, US. When US is followed up with CT for negative results with persistent haematuria, it dominates the initial use of CT alone, with a saving of pounds sterling 235,000 for the evaluation of 1000 patients. The model for investigation of the lower urinary tract showed that for low-risk patients the use of immediate cystoscopy could be avoided if cystoscopy were used for follow-up patients with a negative initial test using tumour markers and/or cytology, resulting in a saving of pounds sterling 483,000 for the evaluation of 1000 patients. The clinical and economic impact on delayed detection of both upper and lower urinary tract tumours through the use of follow-up testing should be evaluated in future studies. There are insufficient data currently available to derive an evidence-based algorithm of the diagnostic pathway for haematuria. A hypothetical algorithm based on the opinion and practice of clinical experts in the review team, other published algorithms and the results of economic modelling is presented in this report. This algorithm is presented, for comparative purposes, alongside current US and UK guidelines. The ideas contained in these algorithms and the specific questions outlined should form the basis of future research. Quality assessment of the diagnostic accuracy studies included in this review highlighted several areas of deficiency.

Clinical applicability and cost of a 46-gene panel for genomic analysis of solid tumours: Retrospective validation and prospective audit in the UK National Health Service

PubMed Central

Kaur, Kulvinder; Camps, Carme; Kaisaki, Pamela; Gupta, Avinash; Talbot, Denis; Middleton, Mark; Henderson, Shirley; Cutts, Anthony; Vavoulis, Dimitrios V.; Housby, Nick; Taylor, Jenny C.; Schuh, Anna

2017-01-01

Background Single gene tests to predict whether cancers respond to specific targeted therapies are performed increasingly often. Advances in sequencing technology, collectively referred to as next generation sequencing (NGS), mean the entire cancer genome or parts of it can now be sequenced at speed with increased depth and sensitivity. However, translation of NGS into routine cancer care has been slow. Healthcare stakeholders are unclear about the clinical utility of NGS and are concerned it could be an expensive addition to cancer diagnostics, rather than an affordable alternative to single gene testing. Methods and findings We validated a 46-gene hotspot cancer panel assay allowing multiple gene testing from small diagnostic biopsies. From 1 January 2013 to 31 December 2013, solid tumour samples (including non-small-cell lung carcinoma [NSCLC], colorectal carcinoma, and melanoma) were sequenced in the context of the UK National Health Service from 351 consecutively submitted prospective cases for which treating clinicians thought the patient had potential to benefit from more extensive genetic analysis. Following histological assessment, tumour-rich regions of formalin-fixed paraffin-embedded (FFPE) sections underwent macrodissection, DNA extraction, NGS, and analysis using a pipeline centred on Torrent Suite software. With a median turnaround time of seven working days, an integrated clinical report was produced indicating the variants detected, including those with potential diagnostic, prognostic, therapeutic, or clinical trial entry implications. Accompanying phenotypic data were collected, and a detailed cost analysis of the panel compared with single gene testing was undertaken to assess affordability for routine patient care. Panel sequencing was successful for 97% (342/351) of tumour samples in the prospective cohort and showed 100% concordance with known mutations (detected using cobas assays). At least one mutation was identified in 87% (296/342) of tumours. A locally actionable mutation (i.e., available targeted treatment or clinical trial) was identified in 122/351 patients (35%). Forty patients received targeted treatment, in 22/40 (55%) cases solely due to use of the panel. Examination of published data on the potential efficacy of targeted therapies showed theoretically actionable mutations (i.e., mutations for which targeted treatment was potentially appropriate) in 66% (71/107) and 39% (41/105) of melanoma and NSCLC patients, respectively. At a cost of £339 (US$449) per patient, the panel was less expensive locally than performing more than two or three single gene tests. Study limitations include the use of FFPE samples, which do not always provide high-quality DNA, and the use of “real world” data: submission of cases for sequencing did not always follow clinical guidelines, meaning that when mutations were detected, patients were not always eligible for targeted treatments on clinical grounds. Conclusions This study demonstrates that more extensive tumour sequencing can identify mutations that could improve clinical decision-making in routine cancer care, potentially improving patient outcomes, at an affordable level for healthcare providers. PMID:28196074

JAG1 mutations are found in approximately one third of patients presenting with only one or two clinical features of Alagille syndrome.

PubMed

Guegan, K; Stals, K; Day, M; Turnpenny, P; Ellard, S

2012-07-01

Alagille syndrome is a multisystem disorder characterized by highly variable expressivity, most frequently caused by heterozygous JAG1 gene mutations. Classic diagnostic criteria combine the presence of bile duct paucity on liver biopsy with three of five systems affected; liver, heart, skeleton, eye and dysmorphic facies. The aim of this study was to determine the prevalence and distribution of JAG1 mutations in patients referred for routine clinical diagnostic testing. Clinical data were available for 241 patients from 135 families. The index cases were grouped according to the number of systems affected (heart, liver, skeletal, eye and facies) and the mutation frequency calculated for each group. JAG1 mutations were identified in 59/135 (44%) probands. The highest mutation detection rates were observed in patients with the most frequent presenting features of Alagille syndrome; ranging from 20% (one system) to 86% (five systems). The overall mutation pick-up rate in a clinical diagnostic setting was lower than in previous research studies. Identification of a JAG1 gene mutation is particularly useful for those patients with atypical or mild Alagille syndrome who do not meet classic diagnostic criteria as it provides a definite molecular diagnosis and allows accurate genetic counselling for the family. © 2011 John Wiley & Sons A/S.

Proposals or findings for a new approach about how to define and diagnose premature ejaculation.

PubMed

Wang, Weifu; Kumar, Pardeep; Minhas, Suks; Ralph, David

2005-09-01

To review and present the proposals or findings for a new approach about how to define and diagnose premature ejaculation (PE). Using Medline to search for international peer reviewed manuscripts published from 1996 to 2004 about the definition and diagnosis of PE. PE, to date, has not a universally agreed definition and diagnostic criterion. Many definitions are partial, subjective and nonspecific. An ideal definition or diagnostic criterion should consist of intravaginal ejaculatory latency time (IELT), the ability to control over ejaculation, the extent of male sexual satisfaction, the extent of female sexual satisfaction, the frequency of female sexual partner reaching orgasm and the extent of psychological and pathological factors. Therefore, the Chinese Index of Premature Ejaculation (CIPE) seems an ideal tool and criterion used to diagnose PE due to including all the elements above. In the majority of cases, PE is the result of a mix of psychogenic, physiological and organic factors. So, besides some routine tests such as urine routine test, endocrine hormone assay, psychosexual counseling, couple evaluation and physical examination, prostate examination, serum leptin assay, semen magnesium assessment and glans hypersensitivity measurement, are suggested to be performed in the diagnosis of PE. Although elucidated by two clinical trials and further confirmed, serum leptin assay seems a promising and objective marker to diagnose PE because it is related to the serotonergic system whose disorder has been confirmed to contribute to the etiology of PE. None of these definitions and diagnoses has been accepted as a universal agreement of PE. CIPE seems an ideal tool and criterion used to diagnose PE and leptin maybe become a promising and objective marker for PE.

Physiotherapy for plantar fasciitis: a UK-wide survey of current practice.

PubMed

Grieve, Rob; Palmer, Shea

2017-06-01

To identify how United Kingdom (UK) physiotherapists currently diagnose, assess and manage plantar fasciitis in routine practice. Online questionnaire survey. Practising physiotherapists across the UK who treat patients with plantar fasciitis. Physiotherapists were approached via 'interactive Chartered Society of Physiotherapy (CSP)' online networks and an email database of clinical educators in South West England. An online questionnaire was developed by reviewing similar existing physiotherapy surveys and consultation with experienced musculoskeletal researchers/clinicians. Descriptive statistics were used to analyse the data. 285 physiotherapists responded, with 257 complete survey responses. Pain on palpation and early morning pain were the most common diagnostic criteria, with some physiotherapists using no formal test criteria. Advice (237/257, 92%), plantar fasciitis pathology education (207/257, 81%) and general stretching exercises (189/257, 74%) were most routinely used. Prefabricated orthotics, custom made orthotics and night splints were seldom always used. For the manual therapy approach, the most frequently used modalities were massage, myofascial release, specific soft tissue mobilisations and myofascial trigger point therapy. Commonly used outcome measures were pain assessment, functional tests and range of movement. Physiotherapists appeared to follow most of the established diagnostic criteria for PF, but have not followed established outcome measure guidelines. Advice as well as education with an emphasis on self-management including calf/hamstring stretching was the most commonly reported treatment approach. There was uncertainty whether this approach accurately reflected clinical practice used throughout the UK, owing to potential response bias/unknown response rate and the low number of patients with PF treated by the respondents. Copyright © 2016 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Potentially pathogenic germline CHEK2 c.319+2T>A among multiple early-onset cancer families.

PubMed

Dominguez-Valentin, Mev; Nakken, Sigve; Tubeuf, Hélène; Vodak, Daniel; Ekstrøm, Per Olaf; Nissen, Anke M; Morak, Monika; Holinski-Feder, Elke; Martins, Alexandra; Møller, Pål; Hovig, Eivind

2018-01-01

To study the potential contribution of genes other than BRCA1/2, PTEN, and TP53 to the biological and clinical characteristics of multiple early-onset cancers in Norwegian families, including early-onset breast cancer, Cowden-like and Li-Fraumeni-like syndromes (BC, CSL and LFL, respectively). The Hereditary Cancer Biobank from the Norwegian Radium Hospital was used to identify early-onset BC, CSL or LFL for whom no pathogenic variants in BRCA1/2, PTEN, or TP53 had been found in routine diagnostic DNA sequencing. Forty-four cancer susceptibility genes were selected and analyzed by our in-house designed TruSeq amplicon-based assay for targeted sequencing. Protein- and RNA splicing-dedicated in silico analyses were performed for all variants of unknown significance (VUS). Variants predicted as the more likely to affect splicing were experimentally analyzed by minigene assay. We identified a CSL individual carrying a variant in CHEK2 (c.319+2T>A, IVS2), here considered as likely pathogenic. Out of the five VUS (BRCA2, CDH1, CHEK2, MAP3K1, NOTCH3) tested in the minigene splicing assay, only NOTCH3 c.14090C>T (p.Ser497Leu) showed a significant effect on RNA splicing, notably by inducing partial skipping of exon 9. Among 13 early-onset BC, CSL and LFL patients, gene panel sequencing identified a potentially pathogenic variant in CHEK2 that affects a canonical RNA splicing signal. Our study provides new information on genetic loci that may affect the risk of developing cancer in these patients and their families, demonstrating that genes presently not routinely tested in molecular diagnostic settings may be important for capturing cancer predisposition in these families.

Systematic internal transcribed spacer sequence analysis for identification of clinical mold isolates in diagnostic mycology: a 5-year study.

PubMed

Ciardo, Diana E; Lucke, Katja; Imhof, Alex; Bloemberg, Guido V; Böttger, Erik C

2010-08-01

The implementation of internal transcribed spacer (ITS) sequencing for routine identification of molds in the diagnostic mycology laboratory was analyzed in a 5-year study. All mold isolates (n = 6,900) recovered in our laboratory from 2005 to 2009 were included in this study. According to a defined work flow, which in addition to troublesome phenotypic identification takes clinical relevance into account, 233 isolates were subjected to ITS sequence analysis. Sequencing resulted in successful identification for 78.6% of the analyzed isolates (57.1% at species level, 21.5% at genus level). In comparison, extended in-depth phenotypic characterization of the isolates subjected to sequencing achieved taxonomic assignment for 47.6% of these, with a mere 13.3% at species level. Optimization of DNA extraction further improved the efficacy of molecular identification. This study is the first of its kind to testify to the systematic implementation of sequence-based identification procedures in the routine workup of mold isolates in the diagnostic mycology laboratory.

External quality assurance of HER2 fluorescence in situ hybridisation testing: results of a UK NEQAS pilot scheme

PubMed Central

Bartlett, John M S; Ibrahim, Merdol; Jasani, Bharat; Morgan, John M; Ellis, Ian; Kay, Elaine; Magee, Hilary; Barnett, Sarah; Miller, Keith

2007-01-01

Background and Aims Trastuzumab provides clinical benefit for advanced and early breast cancer patients whose tumours over‐express or have gene amplification of the HER2 oncogene. The UK National External Quality Assessment Scheme (NEQAS) for immunohistochemical testing was established to assess and improve the quality of HER2 immunohistochemical testing. However, until recently, no provision was available for HER2 fluorescence in situ hybridisation (FISH) testing. A pilot scheme was set up to review the performance of FISH testing in clinical diagnostic laboratories. Methods FISH was performed in 6 reference and 31 participating laboratories using a cell line panel with known HER2 status. Results Using results from reference laboratories as a criterion for acceptable performance, 60% of all results returned by participants were appropriate and 78% either appropriate or acceptable. However, 22.4% of results returned were deemed inappropriate, including 13 cases (4.2%) where a misdiagnosis would have been made had these been clinical specimens. Conclusions The results of three consecutive runs show that both reference laboratories and a proportion of routine clinical diagnostic (about 25%) centres can consistently achieve acceptable quality control of HER2 testing. Data from a significant proportion of participating laboratories show that further steps are required, including those taken via review of performance under schemes such as NEQAS, to improve quality of HER2 testing by FISH in the “real world”. PMID:16963466

Coexistence of two clades of enterovirus D68 in pediatric Swedish patients in the summer and fall of 2014.

PubMed

Dyrdak, Robert; Rotzén-Östlund, Maria; Samuelson, Agneta; Eriksson, Margareta; Albert, Jan

2015-01-01

In 2014, an outbreak of enterovirus D68 (EV-D68) was observed in North America, with cases of severe respiratory illness and a possible etiological link to cases of acute flaccid paralysis. EV-D68 has also been reported from European countries, but no data from Sweden are available. This study investigated respiratory specimens collected during July-October 2014 from 30 Swedish children aged 0-9 years who were positive for enterovirus and/or rhinovirus in routine clinical PCR. Seven samples were typed as EV-D68 by VP4/VP2 sequencing. Two genetically distinct EV-D68 variants coexisted. Six viruses belonged to clade B, the variant involved in the North American outbreak, and one virus belonged to clade A. Respiratory illness was the major symptom among EV-D68 infected patients and all fully recovered. This is the first report of EV-D68 in Sweden. Considering the current epidemiological situation, genotyping and specific EV-D68 testing should be considered in patients with severe respiratory illness who test positive for enterovirus or rhinovirus in routine diagnostics.

Rapid targeted somatic mutation analysis of solid tumors in routine clinical diagnostics.

PubMed

Magliacane, Gilda; Grassini, Greta; Bartocci, Paola; Francaviglia, Ilaria; Dal Cin, Elena; Barbieri, Gianluca; Arrigoni, Gianluigi; Pecciarini, Lorenza; Doglioni, Claudio; Cangi, Maria Giulia

2015-10-13

Tumor genotyping is an essential step in routine clinical practice and pathology laboratories face a major challenge in being able to provide rapid, sensitive and updated molecular tests. We developed a novel mass spectrometry multiplexed genotyping platform named PentaPanel to concurrently assess single nucleotide polymorphisms in 56 hotspots of the 5 most clinically relevant cancer genes, KRAS, NRAS, BRAF, EGFR and PIK3CA for a total of 221 detectable mutations. To both evaluate and validate the PentaPanel performance, we investigated 1025 tumor specimens of 6 different cancer types (carcinomas of colon, lung, breast, pancreas, and biliary tract, and melanomas), systematically addressing sensitivity, specificity, and reproducibility of our platform. Sanger sequencing was also performed for all the study samples. Our data showed that PentaPanel is a high throughput and robust tool, allowing genotyping for targeted therapy selection of 10 patients in the same run, with a practical turnaround time of 2 working days. Importantly, it was successfully used to interrogate different DNAs isolated from routinely processed specimens (formalin-fixed paraffin embedded, frozen, and cytological samples), covering all the requirements of clinical tests. In conclusion, the PentaPanel platform can provide an immediate, accurate and cost effective multiplex approach for clinically relevant gene mutation analysis in many solid tumors and its utility across many diseases can be particularly relevant in multiple clinical trials, including the new basket trial approach, aiming to identify appropriate targeted drug combination strategies.

Evidence-based guideline summary: Evaluation, diagnosis, and management of facioscapulohumeral muscular dystrophy

PubMed Central

Tawil, Rabi; Kissel, John T.; Heatwole, Chad; Pandya, Shree; Gronseth, Gary; Benatar, Michael

2015-01-01

Objective: To develop recommendations for the evaluation, diagnosis, prognostication, and treatment of facioscapulohumeral muscular dystrophy (FSHD) from a systematic review and analysis of the evidence. Methods: Relevant articles were analyzed in accordance with the American Academy of Neurology classification of evidence schemes for diagnostic, prognostic, and treatment studies. Recommendations were linked to the strength of the evidence and other factors. Results and recommendations: Available genetic testing for FSHD type 1 is highly sensitive and specific. Although respiratory insufficiency occurs rarely in FSHD, patients with severe FSHD should have routine pulmonary function testing. Routine cardiac screening is not necessary in patients with FSHD without cardiac symptoms. Symptomatic retinal vascular disease is very rare in FSHD. Exudative retinopathy, however, is potentially preventable, and patients with large deletions should be screened through dilated indirect ophthalmoscopy. The prevalence of clinically relevant hearing loss is not clear. In clinical practice, patients with childhood-onset FSHD may have significant hearing loss. Because undetected hearing loss may impair language development, screening through audiometry is recommended for such patients. Musculoskeletal pain is common in FSHD and treating physicians should routinely inquire about pain. There is at present no effective pharmacologic intervention in FSHD. Available studies suggest that scapular fixation is safe and effective. Surgical scapular fixation might be cautiously offered to selected patients. Aerobic exercise in FSHD appears to be safe and potentially beneficial. On the basis of the evidence, patients with FSHD might be encouraged to engage in low-intensity aerobic exercises. PMID:26215877

A systematic review of the clinical, public health and cost-effectiveness of rapid diagnostic tests for the detection and identification of bacterial intestinal pathogens in faeces and food.

PubMed

Abubakar, I; Irvine, L; Aldus, C F; Wyatt, G M; Fordham, R; Schelenz, S; Shepstone, L; Howe, A; Peck, M; Hunter, P R

2007-09-01

To determine the diagnostic accuracy of tests for the rapid diagnosis of bacterial food poisoning in clinical and public health practice and to estimate the cost-effectiveness of these assays in a hypothetical population in order to inform policy on the use of these tests. Studies evaluating diagnostic accuracy of rapid tests were retrieved using electronic databases and handsearching reference lists and key journals. Hospital laboratories and test manufacturers were contacted for cost data, and clinicians involved in the care of patients with food poisoning were invited to discuss the conclusions of this review using the nominal group technique. A systematic review of the current medical literature on assays used for the rapid diagnosis of bacterial food poisoning was carried out. Specific organisms under review were Salmonella, Campylobacter, Escherichia coli O157, Staphylococcus aureus, Clostridium perfringens and Bacillus cereus. Data extraction was undertaken using standardised data extraction forms. Where a sufficient number of studies evaluating comparable tests were identified, meta-analysis was performed. A decision analytic model was developed, using effectiveness data from the review and cost data from hospitals and manufacturers, which contributed to an assessment of the cost-effectiveness of rapid tests in a hypothetical UK population. Finally, diagnostic accuracy and cost-effectiveness results were presented to a focus group of GPs, microbiologists and consultants in communicable disease control, to assess professional opinion on the use of rapid tests in the diagnosis of food poisoning. Good test performance levels were observed with rapid test methods, especially for polymerase chain reaction (PCR) assays. The estimated levels of diagnostic accuracy using the area under the curve of the summary receiver operating characteristic curve was very high. Indeed, although traditional culture is the natural reference test to use for comparative statistical analysis, on many occasions the rapid test outperforms culture, detecting additional 'truly' positive cases of food-borne illness. The significance of these additional positives requires further investigation. Economic modelling suggests that adoption of rapid tests in combination with routine culture is unlikely to be cost-effective, however, as the cost of rapid technologies decreases; total replacement with rapid technologies may be feasible. Despite the relatively poor quality of reporting of studies evaluating rapid detection methods, the reviewed evidence shows that PCR for Campylobacter, Salmonella and E. coli O157 is potentially very successful in identifying pathogens, possibly detecting more than the number currently reported using culture. Less is known about the benefits of testing for B. cereus, C. perfringens and S. aureus. Further investigation is needed on how clinical outcomes may be altered if test results are available more quickly and at a greater precision than in the current practice of bacterial culture.

Clinical and public health implications of acute and early HIV detection and treatment: a scoping review.

PubMed

Rutstein, Sarah E; Ananworanich, Jintanat; Fidler, Sarah; Johnson, Cheryl; Sanders, Eduard J; Sued, Omar; Saez-Cirion, Asier; Pilcher, Christopher D; Fraser, Christophe; Cohen, Myron S; Vitoria, Marco; Doherty, Meg; Tucker, Joseph D

2017-06-28

The unchanged global HIV incidence may be related to ignoring acute HIV infection (AHI). This scoping review examines diagnostic, clinical, and public health implications of identifying and treating persons with AHI. We searched PubMed, in addition to hand-review of key journals identifying research pertaining to AHI detection and treatment. We focused on the relative contribution of AHI to transmission and the diagnostic, clinical, and public health implications. We prioritized research from low- and middle-income countries (LMICs) published in the last fifteen years. Extensive AHI research and limited routine AHI detection and treatment have begun in LMIC. Diagnostic challenges include ease-of-use, suitability for application and distribution in LMIC, and throughput for high-volume testing. Risk score algorithms have been used in LMIC to screen for AHI among individuals with behavioural and clinical characteristics more often associated with AHI. However, algorithms have not been implemented outside research settings. From a clinical perspective, there are substantial immunological and virological benefits to identifying and treating persons with AHI - evading the irreversible damage to host immune systems and seeding of viral reservoirs that occurs during untreated acute infection. The therapeutic benefits require rapid initiation of antiretrovirals, a logistical challenge in the absence of point-of-care testing. From a public health perspective, AHI diagnosis and treatment is critical to: decrease transmission via viral load reduction and behavioural interventions; improve pre-exposure prophylaxis outcomes by avoiding treatment initiation for HIV-seronegative persons with AHI; and, enhance partner services via notification for persons recently exposed or likely transmitting. There are undeniable clinical and public health benefits to AHI detection and treatment, but also substantial diagnostic and logistical barriers to implementation and scale-up. Effective early ART initiation may be critical for HIV eradication efforts, but widespread use in LMIC requires simple and accurate diagnostic tools. Implementation research is critical to facilitate sustainable integration of AHI detection and treatment into existing health systems and will be essential for prospective evaluation of testing algorithms, point-of-care diagnostics, and efficacious and effective first-line regimens.

Clinical and public health implications of acute and early HIV detection and treatment: a scoping review

PubMed Central

Rutstein, Sarah E.; Ananworanich, Jintanat; Fidler, Sarah; Johnson, Cheryl; Sanders, Eduard J.; Sued, Omar; Saez-Cirion, Asier; Pilcher, Christopher D.; Fraser, Christophe; Cohen, Myron S.; Vitoria, Marco; Doherty, Meg; Tucker, Joseph D.

2017-01-01

Abstract Introduction: The unchanged global HIV incidence may be related to ignoring acute HIV infection (AHI). This scoping review examines diagnostic, clinical, and public health implications of identifying and treating persons with AHI. Methods: We searched PubMed, in addition to hand-review of key journals identifying research pertaining to AHI detection and treatment. We focused on the relative contribution of AHI to transmission and the diagnostic, clinical, and public health implications. We prioritized research from low- and middle-income countries (LMICs) published in the last fifteen years. Results and Discussion: Extensive AHI research and limited routine AHI detection and treatment have begun in LMIC. Diagnostic challenges include ease-of-use, suitability for application and distribution in LMIC, and throughput for high-volume testing. Risk score algorithms have been used in LMIC to screen for AHI among individuals with behavioural and clinical characteristics more often associated with AHI. However, algorithms have not been implemented outside research settings. From a clinical perspective, there are substantial immunological and virological benefits to identifying and treating persons with AHI – evading the irreversible damage to host immune systems and seeding of viral reservoirs that occurs during untreated acute infection. The therapeutic benefits require rapid initiation of antiretrovirals, a logistical challenge in the absence of point-of-care testing. From a public health perspective, AHI diagnosis and treatment is critical to: decrease transmission via viral load reduction and behavioural interventions; improve pre-exposure prophylaxis outcomes by avoiding treatment initiation for HIV-seronegative persons with AHI; and, enhance partner services via notification for persons recently exposed or likely transmitting. Conclusions: There are undeniable clinical and public health benefits to AHI detection and treatment, but also substantial diagnostic and logistical barriers to implementation and scale-up. Effective early ART initiation may be critical for HIV eradication efforts, but widespread use in LMIC requires simple and accurate diagnostic tools. Implementation research is critical to facilitate sustainable integration of AHI detection and treatment into existing health systems and will be essential for prospective evaluation of testing algorithms, point-of-care diagnostics, and efficacious and effective first-line regimens. PMID:28691435

Diagnostic utility of the cell block method versus the conventional smear study in pleural fluid cytology.

PubMed

Shivakumarswamy, Udasimath; Arakeri, Surekha U; Karigowdar, Mahesh H; Yelikar, Br

2012-01-01

The cytological examinations of serous effusions have been well-accepted, and a positive diagnosis is often considered as a definitive diagnosis. It helps in staging, prognosis and management of the patients in malignancies and also gives information about various inflammatory and non-inflammatory lesions. Diagnostic problems arise in everyday practice to differentiate reactive atypical mesothelial cells and malignant cells by the routine conventional smear (CS) method. To compare the morphological features of the CS method with those of the cell block (CB) method and also to assess the utility and sensitivity of the CB method in the cytodiagnosis of pleural effusions. The study was conducted in the cytology section of the Department of Pathology. Sixty pleural fluid samples were subjected to diagnostic evaluation for over a period of 20 months. Along with the conventional smears, cell blocks were prepared by using 10% alcohol-formalin as a fixative agent. Statistical analysis with the 'z test' was performed to identify the cellularity, using the CS and CB methods. Mc. Naemer's χ(2)test was used to identify the additional yield for malignancy by the CB method. Cellularity and additional yield for malignancy was 15% more by the CB method. The CB method provides high cellularity, better architectural patterns, morphological features and an additional yield of malignant cells, and thereby, increases the sensitivity of the cytodiagnosis when compared with the CS method.

Additional molecular findings in 11p15-associated imprinting disorders: an urgent need for multi-locus testing.

PubMed

Eggermann, Thomas; Heilsberg, Ann-Kathrin; Bens, Susanne; Siebert, Reiner; Beygo, Jasmin; Buiting, Karin; Begemann, Matthias; Soellner, Lukas

2014-07-01

The chromosomal region 11p15 contains two imprinting control regions (ICRs) and is a key player in molecular processes regulated by genomic imprinting. Genomic as well as epigenetic changes affecting 11p15 are associated either with Silver-Russell syndrome (SRS) or Beckwith-Wiedemann syndrome (BWS). In the last years, a growing number of patients affected by imprinting disorders (IDs) have reported carrying the disease-specific 11p15 hypomethylation patterns as well as methylation changes at imprinted loci at other chromosomal sites (multi-locus methylation defects, MLMD). Furthermore, in several patients, molecular alterations (e.g., uniparental disomies, UPDs) additional to the primary epimutations have been reported. To determine the frequency and distribution of mutations and epimutations in patients referred as SRS or BWS for genetic testing, we retrospectively ascertained our routine patient cohort consisting of 711 patients (SRS, n = 571; BWS, n = 140). As this cohort represents the typical cohort in a routine diagnostic lab without clinical preselection, the detection rates were much lower than those reported from clinically characterized cohorts in the literature (SRS, 19.9%; BWS, 28.6%). Among the molecular subgroups known to be predisposed to MLMD, the frequencies corresponded to that in the literature (SRS, 7.1% in ICR1 hypomethylation carriers; BWS, 20.8% in ICR2 hypomethylation patients). In several patients, more than one epigenetic or genetic disturbance could be identified. Our study illustrates that the complex molecular alterations as well as the overlapping and sometimes unusual clinical findings in patients with imprinting disorders (IDs) often make the decision for a specific imprinting disorder test difficult. We therefore suggest to implement molecular assays in routine ID diagnostics which allow the detection of a broad range of (epi)mutation types (epimutations, UPDs, chromosomal imbalances) and cover the clinically most relevant known ID loci because of the following: (a) Multi-locus tests increase the detection rates as they cover numerous loci. (b) Patients with unexpected molecular alterations are detected. (c) The testing of rare imprinting disorders becomes more efficient and quality of molecular diagnosis increases. (d) The tests identify MLMDs. In the future, the detailed characterization of clinical and molecular findings in ID patients will help us to decipher the complex regulation of imprinting and thereby providing the basis for more directed genetic counseling and therapeutic managements in IDs. Molecular disturbances in patients with imprinting disorders are often not restricted to the disease-specific locus but also affect other chromosomal regions. These additional disturbances include methylation defects, uniparental disomies as well as chromosomal imbalances. The identification of these additional alterations is mandatory for a well-directed genetic counseling. Furthermore, these findings help to decipher the complex regulation of imprinting.

Diagnostic multiplex PCR for toxin genotyping of Clostridium perfringens isolates.

PubMed

Baums, Christoph G; Schotte, Ulrich; Amtsberg, Gunter; Goethe, Ralph

2004-05-20

In this study we provide a protocol for genotyping Clostridium perfringens with a new multiplex PCR. This PCR enables reliable and specific detection of the toxin genes cpa, cpb, etx, iap, cpe and cpb2 from heat lysed bacterial suspensions. The efficiency of the protocol was demonstrated by typing C. perfringens reference strains and isolates from veterinary bacteriological routine diagnostic specimens.

Use of information on disease diagnoses from databases for animal health economic, welfare and food safety purposes: strengths and limitations of recordings.

PubMed

Houe, Hans; Gardner, Ian Andrew; Nielsen, Liza Rosenbaum

2011-01-01

Many animal health, welfare and food safety databases include data on clinical and test-based disease diagnoses. However, the circumstances and constraints for establishing the diagnoses vary considerably among databases. Therefore results based on different databases are difficult to compare and compilation of data in order to perform meta-analysis is almost impossible. Nevertheless, diagnostic information collected either routinely or in research projects is valuable in cross comparisons between databases, but there is a need for improved transparency and documentation of the data and the performance characteristics of tests used to establish diagnoses. The objective of this paper is to outline the circumstances and constraints for recording of disease diagnoses in different types of databases, and to discuss these in the context of disease diagnoses when using them for additional purposes, including research. Finally some limitations and recommendations for use of data and for recording of diagnostic information in the future are given. It is concluded that many research questions have such a specific objective that investigators need to collect their own data. However, there are also examples, where a minimal amount of extra information or continued validation could make sufficient improvement of secondary data to be used for other purposes. Regardless, researchers should always carefully evaluate the opportunities and constraints when they decide to use secondary data. If the data in the existing databases are not sufficiently valid, researchers may have to collect their own data, but improved recording of diagnostic data may improve the usefulness of secondary diagnostic data in the future.

Comparison of microbiological diagnosis of urinary tract infection in young children by routine health service laboratories and a research laboratory: Diagnostic cohort study

PubMed Central

Birnie, Kate; Hay, Alastair D.; Wootton, Mandy; Howe, Robin; MacGowan, Alasdair; Whiting, Penny; Lawton, Michael; Delaney, Brendan; Downing, Harriet; Dudley, Jan; Hollingworth, William; Lisles, Catherine; Little, Paul; O’Brien, Kathryn; Pickles, Timothy; Rumsby, Kate; Thomas-Jones, Emma; Van der Voort, Judith; Waldron, Cherry-Ann; Harman, Kim; Hood, Kerenza; Butler, Christopher C.; Sterne, Jonathan A. C.

2017-01-01

Objectives To compare the validity of diagnosis of urinary tract infection (UTI) through urine culture between samples processed in routine health service laboratories and those processed in a research laboratory. Population and methods We conducted a prospective diagnostic cohort study in 4808 acutely ill children aged <5 years attending UK primary health care. UTI, defined as pure/predominant growth ≥105 CFU/mL of a uropathogen (the reference standard), was diagnosed at routine health service laboratories and a central research laboratory by culture of urine samples. We calculated areas under the receiver-operator curve (AUC) for UTI predicted by pre-specified symptoms, signs and dipstick test results (the “index test”), separately according to whether samples were obtained by clean catch or nappy (diaper) pads. Results 251 (5.2%) and 88 (1.8%) children were classified as UTI positive by health service and research laboratories respectively. Agreement between laboratories was moderate (kappa = 0.36; 95% confidence interval [CI] 0.29, 0.43), and better for clean catch (0.54; 0.45, 0.63) than nappy pad samples (0.20; 0.12, 0.28). In clean catch samples, the AUC was lower for health service laboratories (AUC = 0.75; 95% CI 0.69, 0.80) than the research laboratory (0.86; 0.79, 0.92). Values of AUC were lower in nappy pad samples (0.65 [0.61, 0.70] and 0.79 [0.70, 0.88] for health service and research laboratory positivity, respectively) than clean catch samples. Conclusions The agreement of microbiological diagnosis of UTI comparing routine health service laboratories with a research laboratory was moderate for clean catch samples and poor for nappy pad samples and reliability is lower for nappy pad than for clean catch samples. Positive results from the research laboratory appear more likely to reflect real UTIs than those from routine health service laboratories, many of which (particularly from nappy pad samples) could be due to contamination. Health service laboratories should consider adopting procedures used in the research laboratory for paediatric urine samples. Primary care clinicians should try to obtain clean catch samples, even in very young children. PMID:28199403

Evaluation of the Abbott RealTime HCV assay for quantitative detection of hepatitis C virus RNA.

PubMed

Michelin, Birgit D A; Muller, Zsofia; Stelzl, Evelyn; Marth, Egon; Kessler, Harald H

2007-02-01

The Abbott RealTime HCV assay for quantitative detection of HCV RNA has recently been introduced. In this study, the performance of the Abbott RealTime HCV assay was evaluated and compared to the COBAS AmpliPrep/COBAS TaqMan HCV test. Accuracy, linearity, interassay and intra-assay variations were determined, and a total of 243 routine clinical samples were investigated. When accuracy of the new assay was tested, the majority of results were found to be within +/-0.5 log(10) unit of the results obtained by reference laboratories. Determination of linearity resulted in a quasilinear curve up to 1.0 x 10(6)IU/ml. The interassay variation ranged from 15% to 32%, and the intra-assay variation ranged from 5% to 8%. When clinical samples were tested by the Abbott RealTime HCV assay and the results were compared with those obtained by the COBAS AmpliPrep/COBAS TaqMan HCV test, the results for 93% of all samples with positive results by both tests were found to be within +/-1.0 log(10) unit. The viral loads for all patients measured by the Abbott and Roche assays showed a high correlation (R(2)=0.93); quantitative results obtained by the Abbott assay were found to be lower than those obtained by the Roche assay. The Abbott RealTime HCV assay proved to be suitable for use in the routine diagnostic laboratory. The time to results was similar for both of the assays.

Examining the Test Of Memory Malingering Trial 1 and Word Memory Test Immediate Recognition as screening tools for insufficient effort.

PubMed

Bauer, Lyndsey; O'Bryant, Sid E; Lynch, Julie K; McCaffrey, Robert J; Fisher, Jerid M

2007-09-01

Assessing effort level during neuropsychological evaluations is critical to support the accuracy of cognitive test scores. Many instruments are designed to measure effort, yet they are not routinely administered in neuropsychological assessments. The Test of Memory Malingering (TOMM) and the Word Memory Test (WMT) are commonly administered symptom validity tests with sound psychometric properties. This study examines the use of the TOMM Trial 1 and the WMT Immediate Recognition (IR) trial scores as brief screening tools for insufficient effort through an archival analysis of a combined sample of mild head-injury litigants ( N = 105) who were assessed in forensic private practices. Results show that both demonstrate impressive diagnostic accuracy and calculations of positive and negative predictive power are presented for a range of base rates. These results support the utility of Trial 1 of the TOMM and the WMT IR trial as screening methods for the assessment of insufficient effort in neuropsychological assessments.

Most Scottish neurologists do not apply the 2010 McDonald criteria when diagnosing multiple sclerosis.

PubMed

Lumley, R; Davenport, R; Williams, A

2015-03-01

The diagnostic criteria for multiple sclerosis have evolved over time and currently the 2010 McDonald criteria are the most widely accepted. These criteria allow the diagnosis of multiple sclerosis to be made at the clinically isolated syndrome stage provided certain criteria are met on a single magnetic resonance brain scan. Our hypothesis was that neurologists in Scotland did not use these criteria routinely. We sent a SurveyMonkey questionnaire to all Scottish neurologists (consultants and trainees) regarding the diagnosis of multiple sclerosis. Our questionnaire response rate was 65/99 (66%). Most Scottish neurologists were aware of the criteria and 31/58 (53%) felt that they were using these routinely. However, in a clinical vignette designed to test the application of these criteria, only 5/57 (9%) of neurologists appeared to use them. Scottish neurologists' use of the 2010 McDonald criteria for diagnosis of multiple sclerosis varies from practitioners' perception of their use of these criteria.

Automated classifiers for early detection and diagnosis of retinopathy in diabetic eyes.

PubMed

Somfai, Gábor Márk; Tátrai, Erika; Laurik, Lenke; Varga, Boglárka; Ölvedy, Veronika; Jiang, Hong; Wang, Jianhua; Smiddy, William E; Somogyi, Anikó; DeBuc, Delia Cabrera

2014-04-12

Artificial neural networks (ANNs) have been used to classify eye diseases, such as diabetic retinopathy (DR) and glaucoma. DR is the leading cause of blindness in working-age adults in the developed world. The implementation of DR diagnostic routines could be feasibly improved by the integration of structural and optical property test measurements of the retinal structure that provide important and complementary information for reaching a diagnosis. In this study, we evaluate the capability of several structural and optical features (thickness, total reflectance and fractal dimension) of various intraretinal layers extracted from optical coherence tomography images to train a Bayesian ANN to discriminate between healthy and diabetic eyes with and with no mild retinopathy. When exploring the probability as to whether the subject's eye was healthy (diagnostic condition, Test 1), we found that the structural and optical property features of the outer plexiform layer (OPL) and the complex formed by the ganglion cell and inner plexiform layers (GCL + IPL) provided the highest probability (positive predictive value (PPV) of 91% and 89%, respectively) for the proportion of patients with positive test results (healthy condition) who were correctly diagnosed (Test 1). The true negative, TP and PPV values remained stable despite the different sizes of training data sets (Test 2). The sensitivity, specificity and PPV were greater or close to 0.70 for the retinal nerve fiber layer's features, photoreceptor outer segments and retinal pigment epithelium when 23 diabetic eyes with mild retinopathy were mixed with 38 diabetic eyes with no retinopathy (Test 3). A Bayesian ANN trained on structural and optical features from optical coherence tomography data can successfully discriminate between healthy and diabetic eyes with and with no retinopathy. The fractal dimension of the OPL and the GCL + IPL complex predicted by the Bayesian radial basis function network provides better diagnostic utility to classify diabetic eyes with mild retinopathy. Moreover, the thickness and fractal dimension parameters of the retinal nerve fiber layer, photoreceptor outer segments and retinal pigment epithelium show promise for the diagnostic classification between diabetic eyes with and with no mild retinopathy.

An Assessment of the Likelihood, Frequency, and Content of Verbal Communication Between Radiologists and Women Receiving Screening and Diagnostic Mammography

PubMed Central

Carney, Patricia A.; Kettler, Mark; Cook, Andrea J.; Geller, Berta M.; Karliner, Leah; Miglioretti, Diana L.; Bowles, Erin Aiello; Buist, Diana S.; Gallagher, Thomas H.; Elmore, Joann G.

2009-01-01

Rationale & Objective Research on communication between radiologists and women undergoing screening and diagnostic mammography is limited. We describe community radiologists’ communication practices with patients regarding screening and diagnostic mammogram results and factors associated with frequency of communication. Materials & Methods We received surveys from 257 radiologists (70% of those eligible) about the extent to which they talk to women as part of their healthcare visit for either screening or diagnostic mammograms, whether this occurs if the exam assessment is positive or negative, and how they use estimates of patient risk to convey information about an abnormal exam where the specific finding of cancer is not yet known. We also assessed characteristics of the radiologists to identify associations with more or less frequent communication at the time of the mammogram. Results Two hundred and forty-three radiologists provided complete data (95%). Very few (<6%) reported routinely communicating with women when screening mammograms were either normal or abnormal. Less than half (47%) routinely communicated with women when their diagnostic mammograms were normal, while 77% often or always communicated with women when their diagnostic exams were abnormal. For positive diagnostic exams, female radiologists were more likely to be frequent communicators compared to males (87.1% to 72.8%; p-value = 0.02) and those who spend 40-79% of their time in breast imaging (94.6%) were more likely to be frequent communicators compared to those who spend less time (67.2%-78.9%; p-value = 0.02). Most radiologists convey risk information using general rather than numeric statements (57.7% vs. 28.5%). Conclusions Radiologists are most likely to convey information about diagnostic mammographic findings when results are abnormal. Most radiologists convey risk information using general rather than numeric statements. PMID:19442539

Virological Diagnosis of Central Nervous System Infections by Use of PCR Coupled with Mass Spectrometry Analysis of Cerebrospinal Fluid Samples

PubMed Central

Lévêque, Nicolas; Legoff, Jérôme; Mengelle, Catherine; Mercier-Delarue, Séverine; N'guyen, Yohan; Renois, Fanny; Tissier, Fabien; Simon, François; Izopet, Jacques

2014-01-01

Viruses are the leading cause of central nervous system (CNS) infections, ahead of bacteria, parasites, and fungal agents. A rapid and comprehensive virologic diagnostic testing method is needed to improve the therapeutic management of hospitalized pediatric or adult patients. In this study, we assessed the clinical performance of PCR amplification coupled with electrospray ionization-time of flight mass spectrometry analysis (PCR-MS) for the diagnosis of viral CNS infections. Three hundred twenty-seven cerebrospinal fluid (CSF) samples prospectively tested by routine PCR assays between 2004 and 2012 in two university hospital centers (Toulouse and Reims, France) were retrospectively analyzed by PCR-MS analysis using primers targeted to adenovirus, human herpesviruses 1 to 8 (HHV-1 to -8), polyomaviruses BK and JC, parvovirus B19, and enteroviruses (EV). PCR-MS detected single or multiple virus infections in 190 (83%) of the 229 samples that tested positive by routine PCR analysis and in 10 (10.2%) of the 98 samples that tested negative. The PCR-MS results correlated well with herpes simplex virus 1 (HSV-1), varicella-zoster virus (VZV), and EV detection by routine PCR assays (kappa values [95% confidence intervals], 0.80 [0.69 to 0.92], 0.85 [0.71 to 0.98], and 0.84 [0.78 to 0.90], respectively), whereas a weak correlation was observed with Epstein-Barr virus (EBV) (0.34 [0.10 to 0.58]). Twenty-six coinfections and 16 instances of uncommon neurotropic viruses (HHV-7 [n = 13], parvovirus B19 [n = 2], and adenovirus [n = 1]) were identified by the PCR-MS analysis, whereas only 4 coinfections had been prospectively evidenced using routine PCR assays (P < 0.01). In conclusion, our results demonstrated that PCR-MS analysis is a valuable tool to identify common neurotropic viruses in CSF (with, however, limitations that were identified regarding EBV and EV detection) and may be of major interest in better understanding the clinical impact of multiple or neglected viral neurological infections. PMID:24197874

Who attends a UK diabetes screening programme? Findings from the ADDITION-Cambridge study.

PubMed

Sargeant, L A; Simmons, R K; Barling, R S; Butler, R; Williams, K M; Prevost, A T; Kinmonth, A L; Wareham, N J; Griffin, S J

2010-09-01

One of the factors influencing the cost-effectiveness of population screening for Type 2 diabetes may be uptake. We examined attendance and practice- and individual-level factors influencing uptake at each stage of a diabetes screening programme in general practice. A stepwise screening programme was undertaken among 135, 825 people aged 40-69 years without known diabetes in 49 general practices in East England. The programme included a score based on routinely available data (age, sex, body mass index and prescribed medication) to identify those at high risk, who were offered random capillary blood glucose (RBG) and glycosylated haemoglobin tests. Those screening positive were offered fasting capillary blood glucose (FBG) and confirmatory oral glucose tolerance tests (OGTT). There were 33 539 high-risk individuals invited for a RBG screening test; 24 654 (74%) attended. Ninety-four per cent attended the follow-up FBG test and 82% the diagnostic OGTT. Seventy per cent of individuals completed the screening programme. Practices with higher general practitioner staff complements and those located in more deprived areas had lower uptake for RBG and FBG tests. Male sex and a higher body mass index were associated with lower attendance for RBG testing. Older age, prescription of antihypertensive medication and a higher risk score were associated with higher attendance for FBG and RBG tests. High attendance rates can be achieved by targeted stepwise screening of individuals assessed as high risk by data routinely available in general practice. Different strategies may be required to increase initial attendance, ensure completion of the screening programme, and reduce the risk that screening increases health inequalities.

Detection of Cytomegalovirus (CMV) DNA in EDTA Whole-Blood Samples: Evaluation of the Quantitative artus CMV LightCycler PCR Kit in Conjunction with Automated Sample Preparation▿

PubMed Central

Michelin, Birgit D. A.; Hadžisejdić, Ita; Bozic, Michael; Grahovac, Maja; Hess, Markus; Grahovac, Blaženka; Marth, Egon; Kessler, Harald H.

2008-01-01

Whole blood has been found to be a reliable matrix for the detection and quantitation of cytomegalovirus (CMV) DNA. In this study, the performance of the artus CMV LightCycler (LC) PCR kit in conjunction with automated sample preparation on a BioRobot EZ1 workstation was evaluated. The accuracy, linearity, analytical sensitivity, and inter- and intra-assay variations were determined. A total of 102 clinical EDTA whole-blood samples were investigated, and results were compared with those obtained with the in vitro diagnostics (IVD)/Conformité Européene (CE)-labeled CMV HHV6,7,8 R-gene quantification kit. When the accuracy of the new kit was tested, seven of eight results were found to be within ±0.5 log10 unit of the expected panel results. Determination of linearity resulted in a quasilinear curve over more than 5 log units. The lower limit of detection of the assay was determined to be 139 copies/ml in EDTA whole blood. The interassay variation ranged from 15 to 58%, and the intra-assay variation ranged from 7 to 35%. When clinical samples were tested and the results were compared with those of the routinely used IVD/CE-labeled assay, 53 samples tested positive and 13 samples tested negative by both of the assays. One sample was found to be positive with the artus CMV LC PCR kit only, and 35 samples tested positive with the routinely used assay only. The majority of discrepant results were found with low-titer samples. In conclusion, use of the artus CMV LC PCR kit in conjunction with automated sample preparation on the BioRobot EZ1 workstation may be suitable for the detection and quantitation of CMV DNA in EDTA whole blood in the routine low-throughput laboratory; however, low-positive results may be missed by this assay. PMID:18272703

Detection of cytomegalovirus (CMV) DNA in EDTA whole-blood samples: evaluation of the quantitative artus CMV LightCycler PCR kit in conjunction with automated sample preparation.

PubMed

Michelin, Birgit D A; Hadzisejdic, Ita; Bozic, Michael; Grahovac, Maja; Hess, Markus; Grahovac, Blazenka; Marth, Egon; Kessler, Harald H

2008-04-01

Whole blood has been found to be a reliable matrix for the detection and quantitation of cytomegalovirus (CMV) DNA. In this study, the performance of the artus CMV LightCycler (LC) PCR kit in conjunction with automated sample preparation on a BioRobot EZ1 workstation was evaluated. The accuracy, linearity, analytical sensitivity, and inter- and intra-assay variations were determined. A total of 102 clinical EDTA whole-blood samples were investigated, and results were compared with those obtained with the in vitro diagnostics (IVD)/Conformité Européene (CE)-labeled CMV HHV6,7,8 R-gene quantification kit. When the accuracy of the new kit was tested, seven of eight results were found to be within +/-0.5 log(10) unit of the expected panel results. Determination of linearity resulted in a quasilinear curve over more than 5 log units. The lower limit of detection of the assay was determined to be 139 copies/ml in EDTA whole blood. The interassay variation ranged from 15 to 58%, and the intra-assay variation ranged from 7 to 35%. When clinical samples were tested and the results were compared with those of the routinely used IVD/CE-labeled assay, 53 samples tested positive and 13 samples tested negative by both of the assays. One sample was found to be positive with the artus CMV LC PCR kit only, and 35 samples tested positive with the routinely used assay only. The majority of discrepant results were found with low-titer samples. In conclusion, use of the artus CMV LC PCR kit in conjunction with automated sample preparation on the BioRobot EZ1 workstation may be suitable for the detection and quantitation of CMV DNA in EDTA whole blood in the routine low-throughput laboratory; however, low-positive results may be missed by this assay.

Implementation of large-scale routine diagnostics using whole slide imaging in Sweden: Digital pathology experiences 2006-2013

PubMed Central

Thorstenson, Sten; Molin, Jesper; Lundström, Claes

2014-01-01

Recent technological advances have improved the whole slide imaging (WSI) scanner quality and reduced the cost of storage, thereby enabling the deployment of digital pathology for routine diagnostics. In this paper we present the experiences from two Swedish sites having deployed routine large-scale WSI for primary review. At Kalmar County Hospital, the digitization process started in 2006 to reduce the time spent at the microscope in order to improve the ergonomics. Since 2008, more than 500,000 glass slides have been scanned in the routine operations of Kalmar and the neighboring Linköping University Hospital. All glass slides are digitally scanned yet they are also physically delivered to the consulting pathologist who can choose to review the slides on screen, in the microscope, or both. The digital operations include regular remote case reporting by a few hospital pathologists, as well as around 150 cases per week where primary review is outsourced to a private clinic. To investigate how the pathologists choose to use the digital slides, a web-based questionnaire was designed and sent out to the pathologists in Kalmar and Linköping. The responses showed that almost all pathologists think that ergonomics have improved and that image quality was sufficient for most histopathologic diagnostic work. 38 ± 28% of the cases were diagnosed digitally, but the survey also revealed that the pathologists commonly switch back and forth between digital and conventional microscopy within the same case. The fact that two full-scale digital systems have been implemented and that a large portion of the primary reporting is voluntarily performed digitally shows that large-scale digitization is possible today. PMID:24843825

An automated image processing routine for segmentation of cell cytoplasms in high-resolution autofluorescence images

NASA Astrophysics Data System (ADS)

Walsh, Alex J.; Skala, Melissa C.

2014-02-01

The heterogeneity of genotypes and phenotypes within cancers is correlated with disease progression and drug-resistant cellular sub-populations. Therefore, robust techniques capable of probing majority and minority cell populations are important both for cancer diagnostics and therapy monitoring. Herein, we present a modified CellProfiler routine to isolate cytoplasmic fluorescence signal on a single cell level from high resolution auto-fluorescence microscopic images.

Application of Neural Networks for classification of Patau, Edwards, Down, Turner and Klinefelter Syndrome based on first trimester maternal serum screening data, ultrasonographic findings and patient demographics.

PubMed

Catic, Aida; Gurbeta, Lejla; Kurtovic-Kozaric, Amina; Mehmedbasic, Senad; Badnjevic, Almir

2018-02-13

The usage of Artificial Neural Networks (ANNs) for genome-enabled classifications and establishing genome-phenotype correlations have been investigated more extensively over the past few years. The reason for this is that ANNs are good approximates of complex functions, so classification can be performed without the need for explicitly defined input-output model. This engineering tool can be applied for optimization of existing methods for disease/syndrome classification. Cytogenetic and molecular analyses are the most frequent tests used in prenatal diagnostic for the early detection of Turner, Klinefelter, Patau, Edwards and Down syndrome. These procedures can be lengthy, repetitive; and often employ invasive techniques so a robust automated method for classifying and reporting prenatal diagnostics would greatly help the clinicians with their routine work. The database consisted of data collected from 2500 pregnant woman that came to the Institute of Gynecology, Infertility and Perinatology "Mehmedbasic" for routine antenatal care between January 2000 and December 2016. During first trimester all women were subject to screening test where values of maternal serum pregnancy-associated plasma protein A (PAPP-A) and free beta human chorionic gonadotropin (β-hCG) were measured. Also, fetal nuchal translucency thickness and the presence or absence of the nasal bone was observed using ultrasound. The architectures of linear feedforward and feedback neural networks were investigated for various training data distributions and number of neurons in hidden layer. Feedback neural network architecture out performed feedforward neural network architecture in predictive ability for all five aneuploidy prenatal syndrome classes. Feedforward neural network with 15 neurons in hidden layer achieved classification sensitivity of 92.00%. Classification sensitivity of feedback (Elman's) neural network was 99.00%. Average accuracy of feedforward neural network was 89.6% and for feedback was 98.8%. The results presented in this paper prove that an expert diagnostic system based on neural networks can be efficiently used for classification of five aneuploidy syndromes, covered with this study, based on first trimester maternal serum screening data, ultrasonographic findings and patient demographics. Developed Expert System proved to be simple, robust, and powerful in properly classifying prenatal aneuploidy syndromes.

Pragmatic approach to the clinical work-up of patients with putative allergic disease to metallic orthopaedic implants before and after surgery.

PubMed

Thyssen, J P; Menné, T; Schalock, P C; Taylor, J S; Maibach, H I

2011-03-01

Allergic complications following insertion of metallic orthopaedic implants include allergic dermatitis reactions but also extracutaneous complications. As metal-allergic patients and/or surgeons may ask dermatologists and allergologists for advice prior to planned orthopaedic implant surgery, and as surgeons may refer patients with complications following total joint arthroplasty for diagnostic work-up, there is a continuous need for updated guidelines. This review presents published evidence for patch testing prior to surgery and proposes tentative diagnostic criteria which clinicians can rely on in the work-up of patients with putative allergic complications following surgery. Few studies have investigated whether subjects with metal contact allergy have increased risk of developing complications following orthopaedic implant insertion. Metal allergy might in a minority increase the risk of complications caused by a delayed-type hypersensitivity reaction. At present, we do not know how to identify the subgroups of metal contact allergic patients with a potentially increased risk of complications following insertion of a metal implant. We recommend that clinicians should refrain from routine patch testing prior to surgery unless the patient has already had implant surgery with complications suspected to be allergic or has a history of clinical metal intolerance of sufficient magnitude to be of concern to the patient or a health provider. The clinical work-up of a patient suspected of having an allergic reaction to a metal implant should include patch testing and possibly in vitro testing. We propose diagnostic criteria for allergic dermatitis reactions as well as noneczematous complications caused by metal implants. © 2011 The Authors. BJD © 2011 British Association of Dermatologists.

Technology-enabled examinations of cardiac rhythm, optic nerve, oral health, tympanic membrane, gait and coordination evaluated jointly with routine health screenings: an observational study at the 2015 Kumbh Mela in India

PubMed Central

Gupta, Otkrist; Patalano II, Vincent; Mohit, Mrinal; Merchant, Rikin; Subramanian, S V

2018-01-01

Objectives Technology-enabled non-invasive diagnostic screening (TES) using smartphones and other point-of-care medical devices was evaluated in conjunction with conventional routine health screenings for the primary care screening of patients. Design Dental conditions, cardiac ECG arrhythmias, tympanic membrane disorders, blood oxygenation levels, optic nerve disorders and neurological fitness were evaluated using FDA-approved advanced smartphone powered technologies. Routine health screenings were also conducted. A novel remote web platform was developed to allow expert physicians to examine TES data and compare efficacy with routine health screenings. Setting The study was conducted at a primary care centre during the 2015 Kumbh Mela in Maharashtra, India. Participants 494 consenting 18–90 years old adults attending the 2015 Kumbh Mela were tested. Results TES and routine health screenings identified unique clinical conditions in distinct patients. Intraoral fluorescent imaging classified 63.3% of the population with dental caries and periodontal diseases. An association between poor oral health and cardiovascular illnesses was also identified. Tympanic membrane imaging detected eardrum abnormalities in 13.0% of the population, several with a medical history of hearing difficulties. Gait and coordination issues were discovered in eight subjects and one subject had arrhythmia. Cross-correlations were observed between low oxygen saturation and low body mass index (BMI) with smokers (p=0.0087 and p=0.0122, respectively), and high BMI was associated with elevated blood pressure in middle-aged subjects. Conclusions TES synergistically identified clinically significant abnormalities in several subjects who otherwise presented as normal in routine health screenings. Physicians validated TES findings and used routine health screening data and medical history responses for comprehensive diagnoses for at-risk patients. TES identified high prevalence of oral diseases, hypertension, obesity and ophthalmic conditions among the middle-aged and elderly Indian population, calling for public health interventions. PMID:29678964

TESS Data Processing and Quick-look Pipeline

NASA Astrophysics Data System (ADS)

Fausnaugh, Michael; Huang, Xu; Glidden, Ana; Guerrero, Natalia; TESS Science Office

2018-01-01

We describe the data analysis procedures and pipelines for the Transiting Exoplanet Survey Satellite (TESS). We briefly review the processing pipeline developed and implemented by the Science Processing Operations Center (SPOC) at NASA Ames, including pixel/full-frame image calibration, photometric analysis, pre-search data conditioning, transiting planet search, and data validation. We also describe data-quality diagnostic analyses and photometric performance assessment tests. Finally, we detail a "quick-look pipeline" (QLP) that has been developed by the MIT branch of the TESS Science Office (TSO) to provide a fast and adaptable routine to search for planet candidates in the 30 minute full-frame images.

Constipation: understanding mechanisms and management.

PubMed

Costilla, Vanessa C; Foxx-Orenstein, Amy E

2014-02-01

Constipation is a frequently diagnosed gastrointestinal disorder. Symptoms of constipation are common, with the greatest prevalence in the elderly. Evaluation of constipation begins with a detailed medical history and a focused anorectal examination. Diagnostic testing for constipation is not routinely recommended in the initial evaluation in the absence of alarm signs. Key self-management strategies include increased exercise, a high-fiber diet, and toilet training. High-fiber diets can worsen symptoms in some patients who have chronic constipation. Biofeedback is an effective treatment option for patients who have constipation caused by outlet obstruction defecation. A variety of medications are available to remedy constipation. Published by Elsevier Inc.

Sparsely Ionizing Diagnostic and Natural Background Radiations are Likely Preventing Cancer and Other Genomic-Instability-Associated Diseases

PubMed Central

Scott, Bobby R.; Di Palma, Jennifer

2007-01-01

Routine diagnostic X-rays (e.g., chest X-rays, mammograms, computed tomography scans) and routine diagnostic nuclear medicine procedures using sparsely ionizing radiation forms (e.g., beta and gamma radiations) stimulate the removal of precancerous neo-plastically transformed and other genomically unstable cells from the body (medical radiation hormesis). The indicated radiation hormesis arises because radiation doses above an individual-specific stochastic threshold activate a system of cooperative protective processes that include high-fidelity DNA repair/apoptosis (presumed p53 related), an auxiliary apoptosis process (PAM process) that is presumed p53-independent, and stimulated immunity. These forms of induced protection are called adapted protection because they are associated with the radiation adaptive response. Diagnostic X-ray sources, other sources of sparsely ionizing radiation used in nuclear medicine diagnostic procedures, as well as radioisotope-labeled immunoglobulins could be used in conjunction with apopto-sis-sensitizing agents (e.g., the natural phenolic compound resveratrol) in curing existing cancer via low-dose fractionated or low-dose, low-dose-rate therapy (therapeutic radiation hormesis). Evidence is provided to support the existence of both therapeutic (curing existing cancer) and medical (cancer prevention) radiation hormesis. Evidence is also provided demonstrating that exposure to environmental sparsely ionizing radiations, such as gamma rays, protect from cancer occurrence and the occurrence of other diseases via inducing adapted protection (environmental radiation hormesis). PMID:18648608

Non-invasive diagnosis of acute rejection in renal transplant patients using mass spectrometry of urine samples - a multicentre phase 3 diagnostic accuracy study.

PubMed

Zapf, Antonia; Gwinner, Wilfried; Karch, Annika; Metzger, Jochen; Haller, Hermann; Koch, Armin

2015-09-15

Reliable and timely detection of acute rejection in renal transplant patients is important to preserve the allograft function and to prevent premature allograft failure. The current gold standard for the rejection diagnosis is an allograft biopsy which is usually performed upon an unexplained decline in allograft function. Because of the invasiveness of the biopsy, non-invasive tests have been suggested to diagnose acute rejection including mass spectrometry analysis of urine samples. The aim of this study is to examine the diagnostic accuracy of mass spectrometry analysis in urine for the diagnosis of acute rejections using the biopsy as gold-standard. The study is an ongoing prospective, single-arm, multicentre, phase 3 diagnostic accuracy study. It started in October 2011 and will be concluded in December 2015. Patient within the first year after transplantation who are scheduled for a biopsy to clarify unexplained impairment of the allograft are consecutively recruited into the study. The overall sample size (n = 600) was calculated to demonstrate a sensitivity of 83 % and a specificity of 70 % for a one-sided type one error of 2.5 % and a power of 80 % per hypothesis. Biopsy evaluation and mass spectrometry analysis of urine samples (obtained immediately before biopsy) are performed independently by different readers without knowledge from the respective other assessment. The follow-up observation period is 6 months. For the primary analysis, the lower limits of the two-sided 95 % Wald confidence intervals for sensitivity and specificity will be compared with the pre-specified thresholds (83 % for sensitivity and 70 % for specificity). In secondary analyses the predictive values, the diagnostic measures in subgroups, and the clinical course will be assessed. Previous phase 2 diagnostic accuracy studies (in small selected study populations) provided sufficient evidence to suggest mass spectrometry on urine samples as a promising approach to detect acute rejections. This study determines the diagnostic performance of the test in the routine setting of post-transplant patient care, compared to the biopsy-based rejection diagnosis. The next step would be a randomized trial to compare the two diagnostic strategies (including the urine test or not) in relation to patient relevant endpoints. NCT01315067 ; March 14, 2011.

Technical performance of lactate biosensors and a test-strip device during labour.

PubMed

Luttkus, A K; Fotopoulou, C; Sehouli, J; Stupin, J; Dudenhausen, J W

2010-04-01

Lactate in fetal blood has a high diagnostic power to detect fetal compromise due to hypoxia, as lactate allows an estimation of duration and intensity of metabolic acidemia. Biosensor technology allows an instantaneous diagnosis of fetal compromise in the delivery room. The goal of the current investigation is to define the preanalytical and analytical biases of this technology under routine conditions in a labour ward in comparison to test-strip technology, which allows measurement of lactate alone. Three lactate biosensors (RapidLab 865, Siemens Medical Solutions Diagnostics, Bad Nauheim, Germany; Radiometer ABL625 and ABL 700, Radiometer Copenhagen, Denmark) and one test-strip device (Lactate Pro, Oxford Instruments, UK) were evaluated regarding precision in serial and repetitive measurements in over 1350 samples of fetal whole blood. The coefficient of variation (CV) and the standard deviation (SD) were calculated. The average value of all three biosensors was defined as an artificial reference value (refval). Blood tonometry was performed in order to test the quality of respiratory parameters and to simulate conditions of fetal hypoxia (pO (2): 10 and 20 mmHg). The precision of serial measurements of all biosensors indicated a coefficient of variation (CV) between 1.55 and 3.16% with an SD from 0.042 to 0.053 mmol/L. The test-strip device (Lactate Pro) mounted to 0.117 mmol/L and 3.99% (SD, CV). When compared to our reference value (refval) ABL 625 showed the closest correlation of -0.1%, while Siemens RapidLab 865 showed an overestimation of +8.9%, ABL700 an underestimation of -6.2% and Lactate Pro of -3.7%. For routine use all tested biosensors show sufficient precision. The test-strip device shows a slightly higher standard deviation. A direct comparison of measured lactate values from the various devices needs to be interpreted with caution as each method detects different lactate concentrations. Furthermore, the 40 min process of tonometry led to an increase of SD and coefficient of variation in all devices. This results in the important preanalytical finding that the precision of replicated measurements worsens significantly with time. The clinician should be aware of the type of analyser used and of preanalytical biases before making clinical decisions on the basis of lactate values.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shoaf, S.; APS Engineering Support Division

A real-time image analysis system was developed for beam imaging diagnostics. An Apple Power Mac G5 with an Active Silicon LFG frame grabber was used to capture video images that were processed and analyzed. Software routines were created to utilize vector-processing hardware to reduce the time to process images as compared to conventional methods. These improvements allow for more advanced image processing diagnostics to be performed in real time.

The Relationship between Waiting Times and "Adherence" to the Scottish Intercollegiate Guidelines Network 98 Guideline in Autism Spectrum Disorder Diagnostic Services in Scotland

ERIC Educational Resources Information Center

McKenzie, Karen; Forsyth, Kirsty; O'Hare, Anne; McClure, Iain; Rutherford, Marion; Murray, Aja; Irvine, Linda

2016-01-01

The aim of this study was to explore the extent to which the Scottish Intercollegiate Guidelines Network 98 guidelines on the assessment and diagnosis of autism spectrum disorder were adhered to in child autism spectrum disorder diagnostic services in Scotland and whether there was a significant relationship between routine practice which more…

Towards increase of diagnostic efficacy in gynecologic OCT

NASA Astrophysics Data System (ADS)

Kirillin, Mikhail; Panteleeva, Olga; Eliseeva, Darya; Kachalina, Olga; Sergeeva, Ekaterina; Dubasova, Lyubov; Agrba, Pavel; Mikailova, Gyular; Prudnikov, Maxim; Shakhova, Natalia

2013-06-01

Gynecologic applications of optical coherence tomography (OCT) are usually performed in combination with routine diagnostic procedures: laparoscopy and colposcopy. In combination with laparoscopy OCT is employed for inspection of fallopian tubes in cases of unrecognized infertility while in colposcopy it is used to identify cervix pathologies including cancer. In this paper we discuss methods for increasing diagnostic efficacy of OCT application in these procedures. For OCT-laparoscopy we demonstrate independent criteria for pathology recognition which allow to increase accuracy of diagnostics. For OCT-colposcopy we report on application of device for controlled compression allowing to sense the elasticity of the inspected cervix area and distinguish between neoplasia and inflammatory processes.

Noninvasive Diagnosis of Visceral Leishmaniasis: Development and Evaluation of Two Urine-Based Immunoassays for Detection of Leishmania donovani Infection in India

PubMed Central

Ejazi, Sarfaraz Ahmad; Bhattacharya, Pradyot; Bakhteyar, Md. Asjad Karim; Mumtaz, Aquil Ahmad; Pandey, Krishna; Das, Vidya Nand Ravi; Das, Pradeep; Rahaman, Mehebubar; Goswami, Rama Prosad; Ali, Nahid

2016-01-01

Background Visceral Leishmaniasis (VL), a severe parasitic disease, could be fatal if diagnosis and treatment is delayed. Post kala-azar dermal leishmaniasis (PKDL), a skin related outcome, is a potential reservoir for the spread of VL. Diagnostic tests available for VL such as tissue aspiration are invasive and painful although they are capable of evaluating the treatment response. Serological tests although less invasive than tissue aspiration are incompetent to assess cure. Parasitological examination of slit-skin smear along with the clinical symptoms is routinely used for diagnosis of PKDL. Therefore, a noninvasive test with acceptable sensitivity and competency, additionally, to decide cure would be an asset in disease management and control. Methodology/principal findings We describe here, the development of antibody-capture ELISA and field adaptable dipstick test as noninvasive diagnostic tools for VL and PKDL and as a test of cure in VL treatment. Sensitivity and specificity of urine-ELISA were 97.94% (95/97) and 100% (75/75) respectively, for VL. Importantly, dipstick test demonstrated 100% sensitivity (97/97) and specificity (75/75) in VL diagnosis. Degree of agreement of the two methods with tissue aspiration was 98.83% (κ = 0.97) and 100% (κ = 1), for ELISA and dipstick test, respectively. Both the tests had 100% positivity for PKDL (14/14) cases. ELISA and dipstick test illustrated treatment efficacy in about 90% (16/18) VL cases when eventually turned negative after six months of treatment. Conclusions/significance ELISA and dipstick test found immensely effective for diagnosis of VL and PKDL through urine samples thus, may substitute the existing invasive diagnostics. Utility of these tests as indirect methods of monitoring parasite clearance can define infected versus cured. Urine-based dipstick test is simple, sensitive and above all noninvasive method that may help not only in active VL case detection but also to ascertain treatment response. It can therefore, be deployed widely for interventions in disease management of VL particularly in poor resource outskirts. PMID:27741241

Operational challenges in delivering CD4 diagnostics in sub-Saharan Africa.

PubMed

Thairu, L; Katzenstein, D; Israelski, D

2011-07-01

Access to reliable and low cost CD4 T-cell enumeration to stage illness and monitor anti-retroviral therapy remains elusive in resource-limited settings. We report challenges in delivering CD4 testing using the microcapillary Fluorescence-Activated Cell Sorter (FACS) methodology (Guava EasyCD4 instrument Guava Technologies, Hayward) in Burkina Faso and Zimbabwe. Resources, instruments, reagents, and training were provided to local laboratories within the existing infrastructure and data on CD4 were collected from routine laboratory testing. Challenges encountered included frequent instrument breakdown; poor manufacturer maintenance; difficulties in managing reagent stocks; high technician turnover; reliance on antiquated data management systems; redundant service provision; and lack of repeat testing in male HIV+ patients and in patients with higher CD4 counts after initial staging. While adopting newer, less expensive technologies such as fluorescent platforms and point of care tests can facilitate access to lower cost CD4 testing, our experience suggests that supply chain, corporate commitment to implementation, and community factors also require consideration.

Laboratory practice guidelines for detecting and reporting JAK2 and MPL mutations in myeloproliferative neoplasms: a report of the Association for Molecular Pathology.

PubMed

Gong, Jerald Z; Cook, James R; Greiner, Timothy C; Hedvat, Cyrus; Hill, Charles E; Lim, Megan S; Longtine, Janina A; Sabath, Daniel; Wang, Y Lynn

2013-11-01

Recurrent mutations in JAK2 and MPL genes are genetic hallmarks of BCR-ABL1-negative myeloproliferative neoplasms. Detection of JAK2 and MPL mutations has been incorporated into routine diagnostic algorithms for these diseases. This Special Article summarizes results from a nationwide laboratory survey of JAK2 and MPL mutation analysis. Based on the current practice pattern and the literature, this Special Article provides recommendations and guidelines for laboratory practice for detection of mutations in the JAK2 and MPL genes, including clinical manifestations for prompting the mutation analysis, current and recommended methodologies for testing the mutations, and standardization for reporting the test results. This Special Article also points to future directions for genomic testing in BCR-ABL1-negative myeloproliferative neoplasms. Copyright © 2013 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

An influenza A virus agglutination test using antibody-like polymers.

PubMed

Sukjee, Wannisa; Thitithanyanont, Arunee; Wiboon-Ut, Suwimon; Lieberzeit, Peter A; Paul Gleeson, M; Navakul, Krongkaew; Sangma, Chak

2017-10-01

Antibodies are commonly used in diagnostic routines to identify pathogens. The testing protocols are relatively simple, requiring a certain amount of a specific antibody to detect its corresponding pathogen. Antibody functionality can be mimicked by synthesizing molecularly imprinted polymers (MIPs), i.e. polymers that can selectively recognize a given template structure. Thus, MIPs are sometimes termed 'plastic antibody (PA)'. In this study, we have synthesized new granular MIPs using influenza A virus templates by precipitation polymerization. The selective binding of influenza A to the MIP particles was assessed and subsequently contrasted with other viruses. The affinities of influenza A virus towards the MIP was estimated based on an agglutination test by measuring the amount of influenza subtypes absorbed onto the MIPs. The MIPs produced using the H1N1 template showed specific reactivity to H1N1 while those produced using H5N1 and H3N2 templates showed cross-reactivity.

Instrumentation for localized superconducting cavity diagnostics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Conway, Z. A.; Ge, M.; Iwashita, Y.

2017-01-12

Superconducting accelerator cavities are now routinely operated at levels approaching the theoretical limit of niobium. To achieve these operating levels more information than is available from the RF excitation signal is required to characterize and determine fixes for the sources of performance limitations. This information is obtained using diagnostic techniques which complement the analysis of the RF signal. In this paper we describe the operation and select results from three of these diagnostic techniques: the use of large scale thermometer arrays, second sound wave defect location and high precision cavity imaging with the Kyoto camera.

Diagnostic devices for isothermal nucleic acid amplification.

PubMed

Chang, Chia-Chen; Chen, Chien-Cheng; Wei, Shih-Chung; Lu, Hui-Hsin; Liang, Yang-Hung; Lin, Chii-Wann

2012-01-01

Since the development of the polymerase chain reaction (PCR) technique, genomic information has been retrievable from lesser amounts of DNA than previously possible. PCR-based amplifications require high-precision instruments to perform temperature cycling reactions; further, they are cumbersome for routine clinical use. However, the use of isothermal approaches can eliminate many complications associated with thermocycling. The application of diagnostic devices for isothermal DNA amplification has recently been studied extensively. In this paper, we describe the basic concepts of several isothermal amplification approaches and review recent progress in diagnostic device development.

Diagnostic Devices for Isothermal Nucleic Acid Amplification

PubMed Central

Chang, Chia-Chen; Chen, Chien-Cheng; Wei, Shih-Chung; Lu, Hui-Hsin; Liang, Yang-Hung; Lin, Chii-Wann

2012-01-01

Since the development of the polymerase chain reaction (PCR) technique, genomic information has been retrievable from lesser amounts of DNA than previously possible. PCR-based amplifications require high-precision instruments to perform temperature cycling reactions; further, they are cumbersome for routine clinical use. However, the use of isothermal approaches can eliminate many complications associated with thermocycling. The application of diagnostic devices for isothermal DNA amplification has recently been studied extensively. In this paper, we describe the basic concepts of several isothermal amplification approaches and review recent progress in diagnostic device development. PMID:22969402

Modification of two capripoxvirus quantitative real-time PCR assays to improve diagnostic sensitivity and include beta-actin as an internal positive control.

PubMed

Das, Amaresh; Deng, Ming Y; Babiuk, Shawn; McIntosh, Michael T

2017-05-01

Capripoxviruses (CaPVs), consisting of Sheeppox virus (SPV), Goatpox virus (GPV), and Lumpy skin disease virus (LSDV) species, cause economically significant diseases in sheep, goats, and cattle, respectively. Quantitative real-time polymerase chain reaction (qPCR) assays are routinely used for rapid detection of CaPVs in surveillance and outbreak management programs. We further modified and optimized 2 previously published CaPV qPCR assays, referred to as the Balinsky and Bowden assays, by changing commercial PCR reagents used in the tests. The modified assays displayed 100% analytical specificity and showed no apparent changes in analytical sensitivities for detection of CaPVs compared with the original assays. Diagnostic sensitivities, assessed using 50 clinical reference samples from experimentally infected sheep, goats, and cattle, improved from 82% to 92% for the modified Balinsky assay and from 58% to 82% for the modified Bowden assay. The modified qPCR assays were multiplexed for detection of beta-actin as an indicator for potential false-negative results. The multiplex modified qPCR assays exhibited the same diagnostic sensitivities as the singleplex assays suggesting their utility in the detection of CaPVs.