Diagnosing Chronic Pancreatitis: Comparison and Evaluation of Different Diagnostic Tools.

PubMed

Issa, Yama; van Santvoort, Hjalmar C; van Dieren, Susan; Besselink, Marc G; Boermeester, Marja A; Ahmed Ali, Usama

2017-10-01

This study aims to compare the M-ANNHEIM, Büchler, and Lüneburg diagnostic tools for chronic pancreatitis (CP). A cross-sectional analysis of the development of CP was performed in a prospectively collected multicenter cohort including 669 patients after a first episode of acute pancreatitis. We compared the individual components of the M-ANNHEIM, Büchler, and Lüneburg tools, the agreement between tools, and estimated diagnostic accuracy using Bayesian latent-class analysis. A total of 669 patients with acute pancreatitis followed-up for a median period of 57 (interquartile range, 42-70) months were included. Chronic pancreatitis was diagnosed in 50 patients (7%), 59 patients (9%), and 61 patients (9%) by the M-ANNHEIM, Lüneburg, and Büchler tools, respectively. The overall agreement between these tools was substantial (κ = 0.75). Differences between the tools regarding the following criteria led to significant changes in the total number of diagnoses of CP: abdominal pain, recurrent pancreatitis, moderate to marked ductal lesions, endocrine and exocrine insufficiency, pancreatic calcifications, and pancreatic pseudocysts. The Büchler tool had the highest sensitivity (94%), followed by the M-ANNHEIM (87%), and finally the Lüneburg tool (81%). Differences between diagnostic tools for CP are mainly attributed to presence of clinical symptoms, endocrine insufficiency, and certain morphological complications.

The use of anti-Müllerian hormone as diagnostic for gonadectomy status in dogs.

PubMed

Themmen, Axel P N; Kalra, Bhanu; Visser, Jenny A; Kumar, Ajay; Savjani, Gopal; de Gier, Jeffrey; Jaques, Scott

2016-10-01

In the veterinary practice, there is a need for a diagnostic tool to check the gonadal status in female dogs because it may be difficult to determine whether a female animal has been spayed or whether there are ovarian remnants. Although less prevalent, a similar situation pertains to male dogs. Anti-Müllerian hormone (AMH) is an important regulator of gonadal function and is a specific gonadal product that can be determined in circulation. The objective of this study was to develop and test a canine blood AMH assay as a diagnostic tool to determine the presence of functional gonadal tissue in dogs. A prospective study with a training-validation set paradigm was used. A canine AMH assay was developed and serum and plasma AMH concentrations were determined in blood samples from 46 intact female dogs, 48 spayed females, 50 intact males, and 48 castrated males collected at two separate institutes. Using a training-validation set paradigm, it was found that using cutoff values of 1.1 ng/mL (female) and 5.5 ng/mL (male) AMH, the assay reported excellent specificity and sensitivity of 100% and 90% in female dogs, and good specificity and sensitivity of 100% and 76%, in male dogs, respectively. The sensitivity in male dogs could be further enhanced by including a serum testosterone determination. This newly developed canine AMH assay is a valuable diagnostic tool to determine gonadal status in veterinary medicine. Copyright © 2016 Elsevier Inc. All rights reserved.

Integrating exhaled breath diagnostics by disease-sniffing dogs with instrumental laboratory analysis

EPA Science Inventory

Dogs have been studied for many years as a medical diagnostic tool to detect a pre-clinical disease state by sniffing emissions directly from a human or an in vitro biological sample. Some of the studies report high sensitivity and specificity in blinded case-control studies. How...

DIAGNOSTIC STUDY ON FINE PARTICULATE MATTER PREDICTIONS OF CMAQ IN THE SOUTHEASTERN U.S.

EPA Science Inventory

In this study, the authors use the process analysis tool embedded in CMAQ to examine major processes that govern the fate of key pollutants, identify the most influential processes that contribute to model errors, and guide the diagnostic and sensitivity studies aimed at improvin...

Creation of a simple natural language processing tool to support an imaging utilization quality dashboard.

PubMed

Swartz, Jordan; Koziatek, Christian; Theobald, Jason; Smith, Silas; Iturrate, Eduardo

2017-05-01

Testing for venous thromboembolism (VTE) is associated with cost and risk to patients (e.g. radiation). To assess the appropriateness of imaging utilization at the provider level, it is important to know that provider's diagnostic yield (percentage of tests positive for the diagnostic entity of interest). However, determining diagnostic yield typically requires either time-consuming, manual review of radiology reports or the use of complex and/or proprietary natural language processing software. The objectives of this study were twofold: 1) to develop and implement a simple, user-configurable, and open-source natural language processing tool to classify radiology reports with high accuracy and 2) to use the results of the tool to design a provider-specific VTE imaging dashboard, consisting of both utilization rate and diagnostic yield. Two physicians reviewed a training set of 400 lower extremity ultrasound (UTZ) and computed tomography pulmonary angiogram (CTPA) reports to understand the language used in VTE-positive and VTE-negative reports. The insights from this review informed the arguments to the five modifiable parameters of the NLP tool. A validation set of 2,000 studies was then independently classified by the reviewers and by the tool; the classifications were compared and the performance of the tool was calculated. The tool was highly accurate in classifying the presence and absence of VTE for both the UTZ (sensitivity 95.7%; 95% CI 91.5-99.8, specificity 100%; 95% CI 100-100) and CTPA reports (sensitivity 97.1%; 95% CI 94.3-99.9, specificity 98.6%; 95% CI 97.8-99.4). The diagnostic yield was then calculated at the individual provider level and the imaging dashboard was created. We have created a novel NLP tool designed for users without a background in computer programming, which has been used to classify venous thromboembolism reports with a high degree of accuracy. The tool is open-source and available for download at http://iturrate.com/simpleNLP. Results obtained using this tool can be applied to enhance quality by presenting information about utilization and yield to providers via an imaging dashboard. Copyright © 2017 Elsevier B.V. All rights reserved.

[Diagnostic tools for canine parvovirus infection].

PubMed

Proksch, A L; Hartmann, K

2015-01-01

Canine parvovirus (CPV) infection is one of the most important and common infectious diseases in dogs, in particular affecting young puppies when maternal antibodies have waned and vaccine-induced antibodies have not yet developed. The mortality rate remains high. Therefore, a rapid and safe diagnostic tool is essential to diagnose the disease to 1) provide intensive care treatment and 2) to identify virus-shedding animals and thus prevent virus spread. Whilst the detection of antibodies against CPV is considered unsuitable to diagnose the disease, there are several different methods to directly detect complete virus, virus antigen or DNA. Additionally, to test in commercial laboratories, rapid in-house tests based on ELISA are available worldwide. The specificity of the ELISA rapid in-house tests is reported to be excellent. However, results on sensitivity vary and high numbers of false-negative results are commonly reported, which potentially leads to misdiagnosis. Polymerase chain reaction (PCR) is a very sensitive and specific diagnostic tool. It also provides the opportunity to differentiate vaccine strains from natural infection when sequencing is performed after PCR.

Xpert MTB/RIF Assay for Pulmonary Tuberculosis and Rifampicin Resistance in Children: a Meta-Analysis.

PubMed

Wang, X W; Pappoe, F; Huang, Y; Cheng, X W; Xu, D F; Wang, H; Xu, Y H

2015-01-01

The Xpert MTB/RIF assay has been recommended by WHO to replace conventional microscopy, culture, and drug resistance tests. It simultaneously detects both Mycobacterium tuberculosis infection (TB) and resistance to rifampicin (RIF) within two hours. The objective was to review the available research studies on the accuracy of the Xpert MTB/RIF assay for diagnosing pulmonary TB and RIF-resistance in children. A comprehensive search of Pubmed and Embase was performed up to October 28, 2014. We identified published articles estimating the diagnostic accuracy of the Xpert MTB/RIF assay in children with or without HIV using culture or culture plus clinical TB as standard reference. QUADAS-2 tool was used to evaluate the quality of the studies. A summary estimation for sensitivity, specificity, diagnostic odds ratios (DOR), and the area under the summary ROC curve (AUC) was performed. Meta-analysis was used to establish the overall accuracy. 11 diagnostic studies with 3801 patients were included in the systematic review. The overall analysis revealed a moderate sensitivity and high specificity of 65% (95% CI: 61 - 69%) and 99% (95% CI: 98 - 99%), respectively, and a pooled diagnostic odds ratio of 164.09 (95% CI: 111.89 - 240.64). The AUC value was found to be 0.94. The pooled sensitivity and specificity for paediatric rifampicin resistance were 94.0% (95% CI: 80.0 - 93.0%) and 99.0% (95% CI: 95.0 - 98.0%), respectively. Hence, the Xpert MTB/RIF assay has good diagnostic and rifampicin performance for paediatric pulmonary tuberculosis. The Xpert MTB/RIF is sensitive and specific for diagnosing paediatric pulmonary TB. It is also effective in detecting rifamnicin resistance. It can, therefore, be used as an initial diagnostic tool.

The PHQ-PD as a Screening Tool for Panic Disorder in the Primary Care Setting in Spain

PubMed Central

Wood, Cristina Mae; Ruíz-Rodríguez, Paloma; Tomás-Tomás, Patricia; Gracia-Gracia, Irene; Dongil-Collado, Esperanza; Iruarrizaga, M. Iciar

2016-01-01

Introduction Panic disorder is a common anxiety disorder and is highly prevalent in Spanish primary care centres. The use of validated tools can improve the detection of panic disorder in primary care populations, thus enabling referral for specialized treatment. The aim of this study is to determine the accuracy of the Patient Health Questionnaire-Panic Disorder (PHQ-PD) as a screening and diagnostic tool for panic disorder in Spanish primary care centres. Method We compared the psychometric properties of the PHQ-PD to the reference standard, the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) interview. General practitioners referred 178 patients who completed the entire PHQ test, including the PHQ-PD, to undergo the SCID-I. The sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios of the PHQ-PD were assessed. Results The operating characteristics of the PHQ-PD are moderate. The best cut-off score was 5 (sensitivity .77, specificity .72). Modifications to the questionnaire's algorithms improved test characteristics (sensitivity .77, specificity .72) compared to the original algorithm. The screening question alone yielded the highest sensitivity score (.83). Conclusion Although the modified algorithm of the PHQ-PD only yielded moderate results as a diagnostic test for panic disorder, it was better than the original. Using only the first question of the PHQ-PD showed the best psychometric properties (sensitivity). Based on these findings, we suggest the use of the screening questions for screening purposes and the modified algorithm for diagnostic purposes. PMID:27525977

Depression Case Finding in Individuals with Dementia: A Systematic Review and Meta-Analysis.

PubMed

Goodarzi, Zahra S; Mele, Bria S; Roberts, Derek J; Holroyd-Leduc, Jayna

2017-05-01

To compare the diagnostic accuracy of depression case finding tools with a criterion standard in the outpatient setting among adults with dementia. Systematic review and meta-analysis. Studies of older outpatients with dementia. Elderly outpatients (clinic and long-term care) with dementia (N = 3,035). Prevalence of major depression and diagnostic accuracy measures including sensitivity, specificity, and likelihood ratios. From the 11,539 citations, 20 studies were included for qualitative synthesis and 15 for a meta-analysis. Tools included were the Montgomery Åsberg Depression Rating Scale, Cornell Scale for Depression in Dementia (CSDD), Geriatric Depression Scale (GDS), Center for Epidemiologic Studies Depression Scale (CES-D), Hamilton Depression Rating Scale (HDRS), Single Question, Nijmegen Observer-Rated Depression Scale, and Even Briefer Assessment Scale-Depression. The pooled prevalence of depression in individuals with dementia was 30.3% (95% CI = 22.1-38.5). The average age was 75.2 (95% CI = 71.7-78.7), and mean Mini-Mental State Examination scores ranged from 11.2 to 24. The diagnostic accuracy of the individual tools was pooled for the best-reported cutoffs and for each cutoff, if available. The CSDD had a sensitivity of 0.84 (95% CI = 0.73-0.91) and a specificity of 0.80 (95% CI = 0.65-0.90), the 30-item GDS (GDS-30) had a sensitivity of 0.62 (95% CI = 0.45-0.76) and a specificity 0.81 (95% CI = 0.75-0.85), and the HDRS had a sensitivity of 0.86 (95% CI = 0.63-0.96) and a specificity of 0.84 (95% CI = 0.76-0.90). Summary statistics for all tools across best-reported cutoffs had significant heterogeneity. There are many validated tools for the detection of depression in individuals with dementia. Tools that incorporate a physician interview with patient and collateral histories, the CSDD and HDRS, have higher sensitivities, which would ensure fewer false-negatives. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

Issues in contemporary and potential future molecular diagnostics for dengue.

PubMed

Sekaran, Shamala Devi; Soe, Hui Jen

2017-03-01

Dengue has been the most common arbovirus infection worldwide with 2.5 billion people living in over 100 endemic tropical and subtropical regions. Due to the high number of asymptomatic cases and the signs and symptoms being rather unspecific, dengue cases are often under-reported and might influence dengue surveillance programs. Therefore, a rapid, easy to use, inexpensive, and highly sensitive and specific diagnostic tool is essential for early and accurate diagnosis to ease the clinical management of patients as well as for the development of new interventions. Areas covered: This report discusses the contemporary dengue diagnostic tool, mainly from the aspect of molecular diagnosis where an overview of several nuclei acid amplification tests has been included. Potential molecular diagnostic tools such as biosensor and microarray are also discussed in this report. Expert commentary: Rapidness and accuracy in terms of sensitivity and specificity is imperative in dengue diagnosis for both clinical management and surveillance of dengue to ensure early treatment and corrective control measures can be carried out. In the next five years it is expected that there will be newer tests developed using not only the lateral flow techniques but more specifically biosensors and nanotechnology. These new technologies will have to be validated with the appropriate number and category of samples and to address the issue of cross-reactivity.

Emerging applications of fluorescence spectroscopy in medical microbiology field.

PubMed

Shahzad, Aamir; Köhler, Gottfried; Knapp, Martin; Gaubitzer, Erwin; Puchinger, Martin; Edetsberger, Michael

2009-11-26

There are many diagnostic techniques and methods available for diagnosis of medically important microorganisms like bacteria, viruses, fungi and parasites. But, almost all these techniques and methods have some limitations or inconvenience. Most of these techniques are laborious, time consuming and with chances of false positive or false negative results. It warrants the need of a diagnostic technique which can overcome these limitations and problems. At present, there is emerging trend to use Fluorescence spectroscopy as a diagnostic as well as research tool in many fields of medical sciences. Here, we will critically discuss research studies which propose that Fluorescence spectroscopy may be an excellent diagnostic as well as excellent research tool in medical microbiology field with high sensitivity and specificity.

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 ...

Detecting anxiety in individuals with Parkinson disease: A systematic review.

PubMed

Mele, Bria; Holroyd-Leduc, Jayna; Smith, Eric E; Pringsheim, Tamara; Ismail, Zahinoor; Goodarzi, Zahra

2018-01-02

To examine diagnostic accuracy of anxiety detection tools compared with a gold standard in outpatient settings among adults with Parkinson disease (PD). A systematic review was conducted. MEDLINE, EMABASE, PsycINFO, and Cochrane Database of Systematic Reviews were searched to April 7, 2017. Prevalence of anxiety and diagnostic accuracy measures including sensitivity, specificity, and likelihood ratios were gathered. Pooled prevalence of anxiety was calculated using Mantel-Haenszel-weighted DerSimonian and Laird models. A total of 6,300 citations were reviewed with 6 full-text articles included for synthesis. Tools included within this study were the Beck Anxiety Inventory, Geriatric Anxiety Inventory (GAI), Hamilton Anxiety Rating Scale, Hospital Anxiety and Depression Scale-Anxiety, Parkinson's Anxiety Scale (PAS), and Mini-Social Phobia Inventory. Anxiety diagnoses made included generalized anxiety disorder, social phobia, and any anxiety type. Pooled prevalence of anxiety was 30.1% (95% confidence interval 26.1%-34.0%). The GAI had the best-reported sensitivity of 0.86 and specificity of 0.88. The observer-rated PAS had a sensitivity of 0.71 and the highest specificity of 0.91. While there are 6 tools validated for anxiety screening in PD populations, most tools are only validated in single studies. The GAI is brief and easy to use, with a good balance of sensitivity and specificity. The PAS was specifically developed for PD, is brief, and has self-/observer-rated scales, but with lower sensitivity. Health care practitioners involved in PD care need to be aware of available validated tools and choose one that fits their practice. Copyright © 2017 American Academy of Neurology.

[Virtual clinical diagnosis support system of degenerative stenosis of the lumbar spinal canal].

PubMed

Shevelev, I N; Konovalov, N A; Cherkashov, A M; Molodchenkov, A A; Sharamko, T G; Asiutin, D S; Nazarenko, A G

2013-01-01

The aim of the study was to develop a virtual clinical diagnostic support system of degenerative lumbar spinal stenosis on database of spine registry. Choice of criteria's for diagnostic system was made on symptom analysis of 298 patients with lumbar spinal stenosis. Also was analysed a group of patient with disc herniation's for sensitivity and specify assessment of developed diagnostic support system. Represented clinical diagnostic support system allows identifying patients with degenerative lumbar spinal stenosis on stage of patient's primary visit. System sensitivity and specify are 90 and 71% respectively. "Online" mode of diagnostic system in structure of spine registry provides maximal availability for specialists, regardless of their locations. Development of tools "medicine 2.0" is the actual direction for carrying out further researches with which carrying out the centralized baea collection by means of specialized registers helps.

Combining magnetic nanoparticle with biotinylated nanobodies for rapid and sensitive detection of influenza H3N2

PubMed Central

2014-01-01

Our objective is to develop a rapid and sensitive assay based on magnetic beads to detect the concentration of influenza H3N2. The possibility of using variable domain heavy-chain antibodies (nanobody) as diagnostic tools for influenza H3N2 was investigated. A healthy camel was immunized with inactivated influenza H3N2. A nanobody library of 8 × 108 clones was constructed and phage displayed. After three successive biopanning steps, H3N2-specific nanobodies were successfully isolated, expressed in Escherichia coli, and purified. Sequence analysis of the nanobodies revealed that we possessed four classes of nanobodies against H3N2. Two nanobodies were further used to prepare our rapid diagnostic kit. Biotinylated nanobody was effectively immobilized onto the surface of streptavidin magnetic beads. The modified magnetic beads with nanobody capture specifically influenza H3N2 and can still be recognized by nanobodies conjugated to horseradish peroxidase (HRP) conjugates. Under optimized conditions, the present immunoassay exhibited a relatively high sensitive detection with a limit of 50 ng/mL. In conclusion, by combining magnetic beads with specific nanobodies, this assay provides a promising influenza detection assay to develop a potential rapid, sensitive, and low-cost diagnostic tool to screen for influenza infections. PMID:25328501

Combining magnetic nanoparticle with biotinylated nanobodies for rapid and sensitive detection of influenza H3N2

NASA Astrophysics Data System (ADS)

Zhu, Min; Hu, Yonghong; Li, Guirong; Ou, Weijun; Mao, Panyong; Xin, Shaojie; Wan, Yakun

2014-09-01

Our objective is to develop a rapid and sensitive assay based on magnetic beads to detect the concentration of influenza H3N2. The possibility of using variable domain heavy-chain antibodies (nanobody) as diagnostic tools for influenza H3N2 was investigated. A healthy camel was immunized with inactivated influenza H3N2. A nanobody library of 8 × 108 clones was constructed and phage displayed. After three successive biopanning steps, H3N2-specific nanobodies were successfully isolated, expressed in Escherichia coli, and purified. Sequence analysis of the nanobodies revealed that we possessed four classes of nanobodies against H3N2. Two nanobodies were further used to prepare our rapid diagnostic kit. Biotinylated nanobody was effectively immobilized onto the surface of streptavidin magnetic beads. The modified magnetic beads with nanobody capture specifically influenza H3N2 and can still be recognized by nanobodies conjugated to horseradish peroxidase (HRP) conjugates. Under optimized conditions, the present immunoassay exhibited a relatively high sensitive detection with a limit of 50 ng/mL. In conclusion, by combining magnetic beads with specific nanobodies, this assay provides a promising influenza detection assay to develop a potential rapid, sensitive, and low-cost diagnostic tool to screen for influenza infections.

Use of electronic data and existing screening tools to identify clinically significant obstructive sleep apnea.

PubMed

Severson, Carl A; Pendharkar, Sachin R; Ronksley, Paul E; Tsai, Willis H

2015-01-01

To assess the ability of electronic health data and existing screening tools to identify clinically significant obstructive sleep apnea (OSA), as defined by symptomatic or severe OSA. The present retrospective cohort study of 1041 patients referred for sleep diagnostic testing was undertaken at a tertiary sleep centre in Calgary, Alberta. A diagnosis of clinically significant OSA or an alternative sleep diagnosis was assigned to each patient through blinded independent chart review by two sleep physicians. Predictive variables were identified from online questionnaire data, and diagnostic algorithms were developed. The performance of electronically derived algorithms for identifying patients with clinically significant OSA was determined. Diagnostic performance of these algorithms was compared with versions of the STOP-Bang questionnaire and adjusted neck circumference score (ANC) derived from electronic data. Electronic questionnaire data were highly sensitive (>95%) at identifying clinically significant OSA, but not specific. Sleep diagnostic testing-determined respiratory disturbance index was very specific (specificity ≥95%) for clinically relevant disease, but not sensitive (<35%). Derived algorithms had similar accuracy to the STOP-Bang or ANC, but required fewer questions and calculations. These data suggest that a two-step process using a small number of clinical variables (maximizing sensitivity) and objective diagnostic testing (maximizing specificity) is required to identify clinically significant OSA. When used in an online setting, simple algorithms can identify clinically relevant OSA with similar performance to existing decision rules such as the STOP-Bang or ANC.

Software Users Manual (SUM): Extended Testability Analysis (ETA) Tool

NASA Technical Reports Server (NTRS)

Maul, William A.; Fulton, Christopher E.

2011-01-01

This software user manual describes the implementation and use the Extended Testability Analysis (ETA) Tool. The ETA Tool is a software program that augments the analysis and reporting capabilities of a commercial-off-the-shelf (COTS) testability analysis software package called the Testability Engineering And Maintenance System (TEAMS) Designer. An initial diagnostic assessment is performed by the TEAMS Designer software using a qualitative, directed-graph model of the system being analyzed. The ETA Tool utilizes system design information captured within the diagnostic model and testability analysis output from the TEAMS Designer software to create a series of six reports for various system engineering needs. The ETA Tool allows the user to perform additional studies on the testability analysis results by determining the detection sensitivity to the loss of certain sensors or tests. The ETA Tool was developed to support design and development of the NASA Ares I Crew Launch Vehicle. The diagnostic analysis provided by the ETA Tool was proven to be valuable system engineering output that provided consistency in the verification of system engineering requirements. This software user manual provides a description of each output report generated by the ETA Tool. The manual also describes the example diagnostic model and supporting documentation - also provided with the ETA Tool software release package - that were used to generate the reports presented in the manual

Cryptic and Asymptomatic Opisthorchis felineus Infections

PubMed Central

Armignacco, Orlando; Ferri, Fabrizio; Gomez-Morales, Maria Angeles; Caterini, Luciano; Pozio, Edoardo

2013-01-01

We describe the diagnostic difficulties experienced during an opisthorchiasis outbreak. Of 31 infected individuals, 61.3% were asymptomatic, and in the 12 symptomatic individuals, the duration of non-pathognomonic symptoms was shorter than 4 weeks. Serology by enzyme-linked immunosorbent assay and polymerase chain reaction fecal analysis were shown to be the most sensitive diagnostic tools. PMID:23249682

Clinical Validity of the ADI-R in a US-Based Latino Population.

PubMed

Vanegas, Sandra B; Magaña, Sandra; Morales, Miguel; McNamara, Ellyn

2016-05-01

The Autism Diagnostic Interview-Revised (ADI-R) has been validated as a tool to aid in the diagnosis of Autism; however, given the growing diversity in the United States, the ADI-R must be validated for different languages and cultures. This study evaluates the validity of the ADI-R in a US-based Latino, Spanish-speaking population of 50 children and adolescents with ASD and developmental disability. Sensitivity and specificity of the ADI-R as a diagnostic tool were moderate, but lower than previously reported values. Validity of the social reciprocity and restrictive and repetitive behaviors domains was high, but low in the communication domain. Findings suggest that language discordance between caregiver and child may influence reporting of communication symptoms and contribute to lower sensitivity and specificity.

Raman spectroscopy and PCA-SVM as a non-invasive diagnostic tool to identify and classify qualitatively glycated hemoglobin levels in vivo.

PubMed

Villa-Manríquez, J F; Castro-Ramos, J; Gutiérrez-Delgado, F; Lopéz-Pacheco, M A; Villanueva-Luna, A E

2017-08-01

In this study we identify and classify high and low levels of glycated hemoglobin (HbA1c) in healthy volunteers (HV) and diabetic patients (DP). Overall, 86 subjects were evaluated. The Raman spectrum was measured in three anatomical regions of the body: index fingertip, right ear lobe, and forehead. The measurements were performed to compare the difference between the HV and DP (22 well controlled diabetic patients (WCDP) (HbA1c <6.5%), and 49 not controlled diabetic patients (NCDP) (HbA1c ≥6.5%)). Multivariable methods such as principal components analysis (PCA) combined with support vector machine (SVM) were used to develop effective diagnostic algorithms for classification among these groups. The forehead of HV versus WCDP showed the highest sensitivity (100%) and specificity (100%). Sensitivity (100%) and specificity (60%), were highest in the forehead of WCDP, versus NCDP. In HV versus NCDP, the fingertip had the highest sensitivity (100%) and specificity (80%). The efficacy of the diagnostic algorithm by receiver operating characteristic (ROC) curve was confirmed. Overall, our study demonstrated that the combination of Raman spectroscopy and PCA-SVM are feasible non-invasive diagnostic tool in diabetes to classify qualitatively high and low levels of HbA1c in vivo. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diagnostic Tests to Support Late-Stage Control Programs for Schistosomiasis and Soil-Transmitted Helminthiases.

PubMed

Hawkins, Kenneth R; Cantera, Jason L; Storey, Helen L; Leader, Brandon T; de Los Santos, Tala

2016-12-01

Global efforts to address schistosomiasis and soil-transmitted helminthiases (STH) include deworming programs for school-aged children that are made possible by large-scale drug donations. Decisions on these mass drug administration (MDA) programs currently rely on microscopic examination of clinical specimens to determine the presence of parasite eggs. However, microscopy-based methods are not sensitive to the low-intensity infections that characterize populations that have undergone MDA. Thus, there has been increasing recognition within the schistosomiasis and STH communities of the need for improved diagnostic tools to support late-stage control program decisions, such as when to stop or reduce MDA. Failure to adequately address the need for new diagnostics could jeopardize achievement of the 2020 London Declaration goals. In this report, we assess diagnostic needs and landscape potential solutions and determine appropriate strategies to improve diagnostic testing to support control and elimination programs. Based upon literature reviews and previous input from experts in the schistosomiasis and STH communities, we prioritized two diagnostic use cases for further exploration: to inform MDA-stopping decisions and post-MDA surveillance. To this end, PATH has refined target product profiles (TPPs) for schistosomiasis and STH diagnostics that are applicable to these use cases. We evaluated the limitations of current diagnostic methods with regards to these use cases and identified candidate biomarkers and diagnostics with potential application as new tools. Based on this analysis, there is a need to develop antigen-detecting rapid diagnostic tests (RDTs) with simplified, field-deployable sample preparation for schistosomiasis. Additionally, there is a need for diagnostic tests that are more sensitive than the current methods for STH, which may include either a field-deployable molecular test or a simple, low-cost, rapid antigen-detecting test.

Case Report: SPECT/CT as the New Diagnostic Tool for Specific Wrist Pathology.

PubMed

Linde, Musters; Ten Broek, M; Kraan, G A

2017-01-01

Single photon emission computed tomography has been introduced as a promising new diagnostic tool in orthopaedic pathology since the early 90'. Computed tomography, the combined with SPECT, gives insight in the specific sight of wrist pathology. Literature already supports introduction of SPECT/CT in wrist pathology, but clinical application is lagging. A 40yr old patient reported first in 2004 with persisting pain after a right distal radius fracture. Several diagnostics and operative interventions were performed, all unsuccessful. Because of the persisting pain a SPECT-CT was performed which showed a cyst in the hamate bone, which was successfully enucleated. The patient was finally pain free at recent follow-up. With a QDash-score of 43 and a PRW (H) E-DLV-score of 58/150. In this case report, SPECT/CT proved a very sensitive diagnostic tool for specific pathology of the wrist. It offered precise localisation and thereby the clinically suspected diagnosis was confirmed and the patient successfully treated.

Development and clinical evaluation of a rapid diagnostic kit for feline leukemia virus infection.

PubMed

Kim, Won-Shik; Chong, Chom-Kyu; Kim, Hak-Yong; Lee, Gyu-Cheol; Jeong, Wooseog; An, Dong-Jun; Jeoung, Hye-Young; Lee, Jae-In; Lee, Young-Ki

2014-01-01

Feline leukemia virus (FeLV) causes a range of neoplastic and degenerative diseases in cats. To obtain a more sensitive and convenient diagnosis of the disease, we prepared monoclonal antibodies specific for the FeLV p27 to develop a rapid diagnostic test with enhanced sensitivity and specificity. Among these antibodies, we identified two clones (hybridomas 8F8B5 and 8G7D1) that specifically bound to FeLV and were very suitable for a diagnostic kit. The affinity constants for 8F8B5 and 8G7D1 were 0.35 × 10⁸ and 0.86 × 10⁸, respectively. To investigate the diagnostic abilities of the rapid kit using these antibodies, we performed several clinical studies. Assessment of analytical sensitivity revealed that the detection threshold of the rapid diagnostic test was 2 ng/mL for recombinant p27 and 12.5 × 10⁴ IU/mL for FeLV. When evaluating 252 cat sera samples, the kit was found to have a kappa value of 0.88 compared to polymerase chain reaction (PCR), indicating a significant correlation between data from the rapid diagnostic test and PCR. Sensitivity and specificity of the kit were 95.2% (20/21) and 98.5% (257/261), respectively. Our results demonstrated that the rapid diagnostic test would be a suitable diagnostic tool for the rapid detection of FeLV infection in cats.

Accuracy of Urine Color to Detect Equal to or Greater Than 2% Body Mass Loss in Men.

PubMed

McKenzie, Amy L; Muñoz, Colleen X; Armstrong, Lawrence E

2015-12-01

Clinicians and athletes can benefit from field-expedient measurement tools, such as urine color, to assess hydration state; however, the diagnostic efficacy of this tool has not been established. To determine the diagnostic accuracy of urine color assessment to distinguish a hypohydrated state (≥2% body mass loss [BML]) from a euhydrated state (<2% BML) after exercise in a hot environment. Controlled laboratory study. Environmental chamber in a laboratory. Twenty-two healthy men (age = 22 ± 3 years, height = 180.4 ± 8.7 cm, mass = 77.9 ± 12.8 kg, body fat = 10.6% ± 4.6%). Participants cycled at 68% ± 6% of their maximal heart rates in a hot environment (36°C ± 1°C) for 5 hours or until 5% BML was achieved. At the point of each 1% BML, we assessed urine color. Diagnostic efficacy of urine color was assessed using receiver operating characteristic curve analysis, sensitivity, specificity, and likelihood ratios. Urine color was useful as a diagnostic tool to identify hypohydration after exercise in the heat (area under the curve = 0.951, standard error = 0.022; P < .001). A urine color of 5 or greater identified BML ≥2% with 88.9% sensitivity and 84.8% specificity (positive likelihood ratio = 5.87, negative likelihood ratio = 0.13). Under the conditions of acute dehydration due to exercise in a hot environment, urine color assessment can be a valid, practical, inexpensive tool for assessing hydration status. Researchers should examine the utility of urine color to identify a hypohydrated state under different BML conditions.

Bias-corrected diagnostic performance of the naked-eye single-tube red-cell osmotic fragility test (NESTROFT): an effective screening tool for beta-thalassemia.

PubMed

Mamtani, Manju; Jawahirani, Anil; Das, Kishor; Rughwani, Vinky; Kulkarni, Hemant

2006-08-01

It is being increasingly recognized that a majority of the countries in the thalassemia-belt need a cost-effective screening program as the first step towards control of thalassemia. Although the naked eye single tube red cell osmotic fragility test (NESTROFT) has been considered to be a very effective screening tool for beta-thalassemia trait, assessment of its diagnostic performance has been affected with the reference test- and verification-bias. Here, we set out to provide estimates of sensitivity and specificity of NESTROFT corrected for these potential biases. We conducted a cross-sectional diagnostic test evaluation study using data from 1563 subjects from Central India with a high prevalence of beta-thalassemia. We used latent class modelling after ensuring its validity to account for the reference test bias and global sensitivity analysis to control the verification bias. We also compared the results of latent class modelling with those of five discriminant indexes. We observed that across a range of cut-offs for the mean corpuscular volume (MCV) and the hemoglobin A2 (HbA2) concentration the average sensitivity and specificity of NESTROFT obtained from latent class modelling was 99.8 and 83.7%, respectively. These estimates were comparable to those characterizing the diagnostic performance of HbA2, which is considered by many as the reference test to detect beta-thalassemia. After correction for the verification bias these estimates were 93.4 and 97.2%, respectively. Combined with the inexpensive and quick disposition of NESTROFT, these results strongly support its candidature as a screening tool-especially in the resource-poor and high-prevalence settings.

Multiplex PCR Tests for Detection of Pathogens Associated with Gastroenteritis

PubMed Central

Zhang, Hongwei; Morrison, Scott; Tang, Yi-Wei

2016-01-01

Synopsis A wide range of enteric pathogens can cause infectious gastroenteritis. Conventional diagnostic algorithms including culture, biochemical identification, immunoassay and microscopic examination are time consuming and often lack sensitivity and specificity. Advances in molecular technology have as allowed its use as clinical diagnostic tools. Multiplex PCR based testing has made its way to gastroenterology diagnostic arena in recent years. In this article we present a review of recent laboratory developed multiplex PCR tests and current commercial multiplex gastrointestinal pathogen tests. We will focus on two FDA cleared commercial syndromic multiplex tests: Luminex xTAG GPP and Biofire FimArray GI test. These multiplex tests can detect and identify multiple enteric pathogens in one test and provide results within hours. Multiplex PCR tests have shown superior sensitivity to conventional methods for detection of most pathogens. The high negative predictive value of these multiplex tests has led to the suggestion that they be used as screening tools especially in outbreaks. Although the clinical utility and benefit of multiplex PCR test are to be further investigated, implementing these multiplex PCR tests in gastroenterology diagnostic algorithm has the potential to improve diagnosis of infectious gastroenteritis. PMID:26004652

Photoacoustic and ultrasound characterization of bone composition

NASA Astrophysics Data System (ADS)

Lashkari, Bahman; Yang, Lifeng; Liu, Lixian; Tan, Joel W. Y.; Mandelis, Andreas

2015-02-01

This study examines the sensitivity and specificity of backscattered ultrasound (US) and backscattering photoacoustic (PA) signals for bone composition variation assessment. The conventional approach in the evaluation of bone health relies on measurement of bone mineral density (BMD). Although, a crucial and probably the most important parameter, BMD is not the only factor defining the bone health. New trends in osteoporosis research, also pursue the changes in collagen content and cross-links with bone diseases and aging. Therefore, any non-invasive method that can assess any of these parameters can improve the diagnostic tools and also can help with the biomedical studies on the diseases themselves. Our previous studies show that both US and PA are responsive to changes in the BMD, PA is, in addition, sensitive to changes in the collagen content of the bone. Measurements were performed on bone samples before and after mild demineralization and decollagenization at the exact same points. Results show that combining both modalities can enhance the sensitivity and specificity of diagnostic tool.

Conventional and molecular diagnostic strategies for prosthetic joint infections.

PubMed

Esteban, Jaime; Sorlí, Luisa; Alentorn-Geli, Eduard; Puig, Lluís; Horcajada, Juan P

2014-01-01

An accurate diagnosis of prosthetic joint infection (PJI) is the mainstay for an optimized clinical management. This review analyzes different diagnostic strategies of PJI, with special emphasis on molecular diagnostic tools and their current and future applications. Until now, the culture of periprosthetic tissues has been considered the gold standard for the diagnosis of PJI. However, sonication of the implant increases the sensitivity of those cultures and is being increasingly adopted by many centers. Molecular diagnostic methods compared with intraoperative tissue culture, especially if combined with sonication, have a higher sensitivity, a faster turnaround time and are not influenced by previous antimicrobial therapy. However, they still lack a system for detection of antimicrobial susceptibility, which is crucial for an optimized and less toxic therapy of PJI. More studies are needed to assess the clinical value of these methods and their cost-effectiveness.

Polymerase chain reaction: A molecular diagnostic tool in periodontology

PubMed Central

Maheaswari, Rajendran; Kshirsagar, Jaishree Tukaram; Lavanya, Nallasivam

2016-01-01

This review discusses the principles of polymerase chain reaction (PCR) and its application as a diagnostic tool in periodontology. The relevant MEDLINE and PubMed indexed journals were searched manually and electronically by typing PCR, applications of PCR, PCR in periodontics, polymorphism studies in periodontitis, and molecular techniques in periodontology. The searches were limited to articles in English language and the articles describing PCR process and its relation to periodontology were collected and used to prepare a concise review. PCR has now become a standard diagnostic and research tool in periodontology. Various studies reveal that its sensitivity and specificity allow it as a rapid, efficient method of detecting, identifying, and quantifying organism. Different immune and inflammatory markers can be identified at the mRNA expression level, and also the determination of genetic polymorphisms, thus providing the deeper insight into the mechanisms underlying the periodontal disease. PMID:27143822

Analysis of significantly mutated genes as a clinical tool for the diagnosis in a case of lung cancer.

PubMed

Miyashita, Yoshihiro; Hirotsu, Yosuke; Tsutsui, Toshiharu; Higashi, Seishi; Sogami, Yusuke; Kakizaki, Yumiko; Goto, Taichiro; Amemiya, Kenji; Oyama, Toshio; Omata, Masao

2017-01-01

Bronchoendoscopic examination is not necessarily comfortable procedure and limited by its sensitivity, depending on the location and size of the tumor lesion. Patients with a non-diagnostic bronchoendoscopic examination often undergo further invasive examinations. Non-invasive diagnostic tool of lung cancer is desired. A 72-year-old man had a 3.0 cm × 2.5 cm mass lesion in the segment B1 of right lung. Cytological examination of sputum, bronchial washing and curetted samples were all "negative". We could confirm a diagnosis of lung cancer after right upper lung lobe resection pathologically, and also obtained concordant results by genomic analysis using cytological negative samples from airways collected before operation. Genetic analysis showed mutational profiles of both resected specimens and samples from airways were identical. These data clearly indicated the next generation sequencing (NGS) may yield a diagnostic tool to conduct "precision medicine".

Polymerase chain reaction: A molecular diagnostic tool in periodontology.

PubMed

Maheaswari, Rajendran; Kshirsagar, Jaishree Tukaram; Lavanya, Nallasivam

2016-01-01

This review discusses the principles of polymerase chain reaction (PCR) and its application as a diagnostic tool in periodontology. The relevant MEDLINE and PubMed indexed journals were searched manually and electronically by typing PCR, applications of PCR, PCR in periodontics, polymorphism studies in periodontitis, and molecular techniques in periodontology. The searches were limited to articles in English language and the articles describing PCR process and its relation to periodontology were collected and used to prepare a concise review. PCR has now become a standard diagnostic and research tool in periodontology. Various studies reveal that its sensitivity and specificity allow it as a rapid, efficient method of detecting, identifying, and quantifying organism. Different immune and inflammatory markers can be identified at the mRNA expression level, and also the determination of genetic polymorphisms, thus providing the deeper insight into the mechanisms underlying the periodontal disease.

The Diagnostic Accuracy of Cytology for the Diagnosis of Hepatobiliary and Pancreatic Cancers.

PubMed

Al-Hajeili, Marwan; Alqassas, Maryam; Alomran, Astabraq; Batarfi, Bashaer; Basunaid, Bashaer; Alshail, Reem; Alaydarous, Shahad; Bokhary, Rana; Mosli, Mahmoud

2018-06-13

Although cytology testing is considered a valuable method to diagnose tumors that are difficult to access such as hepato-biliary-pancreatic (HBP) malignancies, its diagnostic accuracy remains unclear. We therefore aimed to investigate the diagnostic accuracy of cytology testing for HBP tumors. We performed a retrospective study of all cytology samples that were used to confirm radiologically detected HBP tumors between 2002 and 2016. The cytology techniques used in our center included fine needle aspiration (FNA), brush cytology, and aspiration of bile. Sensitivity, specificity, positive and negative predictive values, and likelihood ratios were calculated in comparison to histological confirmation. From a total of 133 medical records, we calculated an overall sensitivity of 76%, specificity of 74%, a negative likelihood ratio of 0.30, and a positive likelihood ratio of 2.9. Cytology was more accurate in diagnosing lesions of the liver (sensitivity 79%, specificity 57%) and biliary tree (sensitivity 100%, specificity 50%) compared to pancreatic (sensitivity 60%, specificity 83%) and gallbladder lesions (sensitivity 50%, specificity 85%). Cytology was more accurate in detecting primary cancers (sensitivity 77%, specificity 73%) when compared to metastatic cancers (sensitivity 73%, specificity 100%). FNA was the most frequently used cytological technique to diagnose HBP lesions (sensitivity 78.8%). Cytological testing is efficient in diagnosing HBP cancers, especially for hepatobiliary tumors. Given its relative simplicity, cost-effectiveness, and paucity of alternative diagnostic methods, cytology should still be considered as a first-line tool for diagnosing HBP malignancies. © 2018 S. Karger AG, Basel.

Near Infrared Imaging as a Diagnostic Tool for Detecting Enamel Demineralization: An in vivo Study

NASA Astrophysics Data System (ADS)

Lucas, Seth Adam

Background and Objectives: For decades there has been an effort to develop alternative optical methods of imaging dental decay utilizing non-ionizing radiation methods. The purpose of this in-vivo study was to demonstrate whether NIR can be used as a diagnostic tool to evaluate dental caries and to compare the sensitivity and specificity of this method with that of conventional methods, including bitewing x-rays and visual inspection. Materials and Methods: 31 test subjects (n=31) from the UCSF orthodontic clinic undergoing orthodontic treatment with planned premolar extractions were recruited. Calibrated examiners performed caries detection examinations using conventional methods: bitewing radiographs and visual inspection. These findings were compared with the results from NIR examinations: transillumination and reflectance. To confirm the results found in the two different detection methods, a gold standard was used. After teeth were extracted, polarized light microscopy and transverse microradiography were performed. Results: A total of 87 premolars were used in the study. NIR identified the occlusal lesions with a sensitivity of 71% and a specificity of 77%, whereas, the visual examination had a sensitivity of only 40% and a specifity of 39%. For interproximal lesions halfway to DEJ, specificity remained constant, but sensitivity improved to 100% for NIR and 75% for x-rays. Conclusions: The results of this preliminary study demonstrate that NIR is just as effective at detecting enamel interproximal lesions as standard dental x-rays. NIR was more effective at detecting occlusal lesions than visual examination alone. NIR shows promise as an alternative diagnostic tool to the conventional methods of x-rays and visual examination and provides a non-ionizing radiation technique.

The clinical utility and diagnostic performance of magnetic resonance imaging for identification of early and advanced knee osteoarthritis: a systematic review.

PubMed

Quatman, Carmen E; Hettrich, Carolyn M; Schmitt, Laura C; Spindler, Kurt P

2011-07-01

Current diagnostic strategies for detection of structural articular cartilage abnormalities, the earliest structural signs of osteoarthritis, often do not capture the condition until it is too far advanced for the most potential benefit of noninvasive interventions. To systematically review the literature relative to the following questions: (1) Is magnetic resonance imaging (MRI) a valid, sensitive, specific, accurate, and reliable instrument to identify knee articular cartilage abnormalities compared with arthroscopy? (2) Is MRI a sensitive tool that can be utilized to identify early cartilage degeneration? Systematic review. A systematic search was performed in November 2010 using PubMed MEDLINE (from 1966), CINAHL (from 1982), SPORTDiscus (from 1985), SCOPUS (from 1996), and EMBASE (from 1974) databases. Fourteen level I and 13 level II studies were identified that met inclusion criteria and provided information related to diagnostic performance of MRI compared with arthroscopic evaluation. The diagnostic performance of MRI demonstrated a large range of sensitivities, specificities, and accuracies. The sensitivity for identifying articular cartilage abnormalities in the knee joint was reported between 26% and 96%. Specificity and accuracy were reported between 50% and 100% and between 49% and 94%, respectively. The sensitivity, specificity, and accuracy for identifying early osteoarthritis were reported between 0% and 86%, 48% and 95%, and 5% and 94%, respectively. As a result of inconsistencies between imaging techniques and methodological shortcomings of many of the studies, a meta-analysis was not performed, and it was difficult to fully synthesize the information to state firm conclusions about the diagnostic performance of MRI. There is evidence in some MRI protocols that MRI is a relatively valid, sensitive, specific, accurate, and reliable clinical tool for identifying articular cartilage degeneration. Because of heterogeneity of MRI sequences, it is not possible to make definitive conclusions regarding its global clinical utility for guiding diagnosis and treatment strategies. Traumatic sports injuries to the knee may be significant precursor events to early onset of posttraumatic osteoarthritis. Magnetic resonance imaging may aid in early identification of structural injuries to articular cartilage as evidenced by articular cartilage degeneration grading.

The Clinical Utility and Diagnostic Performance of MRI for Identification of Early and Advanced Knee Osteoarthritis: A Systematic Review

PubMed Central

Quatman, Carmen E.; Hettrich, Carolyn M.; Schmitt, Laura C.; Spindler, Kurt P.

2013-01-01

Background Current diagnostic strategies for detection of structural articular cartilage abnormalities, the earliest structural signs of osteoarthritis, often do not capture the condition until it is too far advanced for the most potential benefit of non-invasive interventions. Purpose Systematically review the literature relative to the following questions: (1) Is MRI a valid, sensitive, specific, accurate and reliable instrument to identify knee articular cartilage abnormalities compared to arthroscopy? (2) Is MRI a sensitive tool that can be utilized to identify early cartilage degeneration? Study Design Systematic Review Methods A systematic search was performed in November 2010 using PubMed MEDLINE (from 1966), CINAHL (from 1982), SPORTDiscus (from 1985), and SCOPUS (from 1996) databases. Results Fourteen level I and 13 level II studies were identified that met inclusion criteria and provided information related to diagnostic performance of MRI compared to arthroscopic evaluation. The diagnostic performance of MRI demonstrated a large range of sensitivities, specificities, and accuracies. The sensitivity for identifying articular cartilage abnormalities in the knee joint was reported between 26–96%. Specificity and accuracy was reported between 50–100% and 49–94%, respectively. The sensitivity, specificity, and accuracy for identifying early osteoarthritis were reported between 0–86%, 48–95%, and 5–94%, respectively. As a result of inconsistencies between imaging techniques and methodological shortcomings of many of the studies, a meta-analysis was not performed and it was difficult to fully synthesize the information to state firm conclusions about the diagnostic performance of MRI. Conclusions There is evidence in some MRI protocols that MRI is a relatively valid, sensitive, specific, accurate, and reliable clinical tool for identifying articular cartilage degeneration. Due to heterogeneity of MRI sequences it is not possible to make definitive conclusions regarding its global clinical utility for guiding diagnosis and treatment strategies. Clinical Relevance Traumatic sports injuries to the knee may be significant precursor events to early onset of posttraumatic osteoarthritis. MRI may aid in early identification of structural injuries to articular cartilage as evidenced by articular cartilage degeneration grading. PMID:21730207

Diagnostic performance of an indirect enzyme-linked immunosorbent assay (ELISA) to detect bovine leukemia virus antibodies in bulk-tank milk samples.

PubMed

Nekouei, Omid; Durocher, Jean; Keefe, Greg

2016-07-01

This study assessed the diagnostic performance of a commercial ELISA for detecting bovine leukemia virus antibodies in bulk-tank milk samples from eastern Canada. Sensitivity and specificity of the test were estimated at 97.2% and 100%, respectively. The test was recommended as a cost-efficient tool for large-scale screening programs.

Diagnostic performance of an indirect enzyme-linked immunosorbent assay (ELISA) to detect bovine leukemia virus antibodies in bulk-tank milk samples

PubMed Central

Nekouei, Omid; Durocher, Jean; Keefe, Greg

2016-01-01

This study assessed the diagnostic performance of a commercial ELISA for detecting bovine leukemia virus antibodies in bulk-tank milk samples from eastern Canada. Sensitivity and specificity of the test were estimated at 97.2% and 100%, respectively. The test was recommended as a cost-efficient tool for large-scale screening programs. PMID:27429469

3 Tesla breast MR imaging as a problem-solving tool: Diagnostic performance and incidental lesions

PubMed Central

Spick, Claudio; Szolar, Dieter H. M.; Preidler, Klaus W.; Reittner, Pia; Rauch, Katharina; Brader, Peter; Tillich, Manfred

2018-01-01

Purpose To investigate the diagnostic performance and incidental lesion yield of 3T breast MRI if used as a problem-solving tool. Methods This retrospective, IRB-approved, cross-sectional, single-center study comprised 302 consecutive women (mean: 50±12 years; range: 20–79 years) who were undergoing 3T breast MRI between 03/2013-12/2014 for further workup of conventional and clinical breast findings. Images were read by experienced, board-certified radiologists. The reference standard was histopathology or follow-up ≥ two years. Sensitivity, specificity, PPV, and NPV were calculated. Results were stratified by conventional and clinical breast findings. Results The reference standard revealed 53 true-positive, 243 true-negative, 20 false-positive, and two false-negative breast MRI findings, resulting in a sensitivity, specificity, PPV, and NPV of 96.4% (53/55), 92.4% (243/263), 72.6% (53/73), and 99.2% (243/245), respectively. In 5.3% (16/302) of all patients, incidental MRI lesions classified BI-RADS 3–5 were detected, 37.5% (6/16) of which were malignant. Breast composition and the imaging findings that had led to referral had no significant influence on the diagnostic performance of breast MR imaging (p>0.05). Conclusion 3T breast MRI yields excellent diagnostic results if used as a problem-solving tool independent of referral reasons. The number of suspicious incidental lesions detected by MRI is low, but is associated with a substantial malignancy rate. PMID:29293582

Test Accuracy of Informant-Based Cognitive Screening Tests for Diagnosis of Dementia and Multidomain Cognitive Impairment in Stroke.

PubMed

McGovern, Aine; Pendlebury, Sarah T; Mishra, Nishant K; Fan, Yuhua; Quinn, Terence J

2016-02-01

Poststroke cognitive assessment can be performed using standardized questionnaires designed for family or care givers. We sought to describe the test accuracy of such informant-based assessments for diagnosis of dementia/multidomain cognitive impairment in stroke. We performed a systematic review using a sensitive search strategy across multidisciplinary electronic databases. We created summary test accuracy metrics and described reporting and quality using STARDdem and Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tools, respectively. From 1432 titles, we included 11 studies. Ten papers used the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Four studies described IQCODE for diagnosis of poststroke dementia (n=1197); summary sensitivity: 0.81 (95% confidence interval, 0.60-0.93); summary specificty: 0.83 (95% confidence interval, 0.64-0.93). Five studies described IQCODE as tool for predicting future dementia (n=837); summary sensitivity: 0.60 (95% confidence interval, 0.32-0.83); summary specificity: 0.97 (95% confidence interval, 0.70-1.00). All papers had issues with at least 1 aspect of study reporting or quality. There is a limited literature on informant cognitive assessments in stroke. IQCODE as a diagnostic tool has test properties similar to other screening tools, IQCODE as a prognostic tool is specific but insensitive. We found no papers describing test accuracy of informant tests for diagnosis of prestroke cognitive decline, few papers on poststroke dementia and all included papers had issues with potential bias. © 2015 American Heart Association, Inc.

A new biomarker panel in bronchoalveolar lavage for an improved lung cancer diagnosis.

PubMed

Uribarri, María; Hormaeche, Itsaso; Zalacain, Rafael; Lopez-Vivanco, Guillermo; Martinez, Antonio; Nagore, Daniel; Ruiz-Argüello, M Begoña

2014-10-01

The enormous biological complexity and high mortality rate of lung cancer highlights the need for new global approaches for the discovery of reliable early diagnostic biomarkers. The study of bronchoalveolar lavage samples by proteomic techniques could identify new lung cancer biomarkers and may provide promising noninvasive diagnostic tools able to enhance the sensitivity of current methods. First, an observational prospective study was designed to assess protein expression differences in bronchoalveolar lavages from patients with (n = 139) and without (n = 49) lung cancer, using two-dimensional gel electrophoresis and subsequent protein identification by mass spectrometry. Second, validation of candidate biomarkers was performed by bead-based immunoassays with a different patient cohort (204 patients, 48 controls). Thirty-two differentially expressed proteins were identified in bronchoalveolar lavages, 10 of which were confirmed by immunoassays. The expression levels of APOA1, CO4A, CRP, GSTP1, and SAMP led to a lung cancer diagnostic panel that reached 95% sensitivity and 81% specificity, and the quantification of STMN1 and GSTP1 proteins allowed the two main lung cancer subtypes to be discriminated with 90% sensitivity and 57% specificity. Bronchoalveolar lavage represents a promising noninvasive source of lung cancer specific protein biomarkers with high diagnostic accuracy. Measurement of APOA1, CO4A, CRP, GSTP1, SAMP, and STMN1 in this fluid may be a useful tool for lung cancer diagnosis, although a further validation in a larger clinical set is required for early stages.

Interferometric Reflectance Imaging Sensor (IRIS)—A Platform Technology for Multiplexed Diagnostics and Digital Detection

PubMed Central

Avci, Oguzhan; Lortlar Ünlü, Nese; Yalçın Özkumur, Ayça; Ünlü, M. Selim

2015-01-01

Over the last decade, the growing need in disease diagnostics has stimulated rapid development of new technologies with unprecedented capabilities. Recent emerging infectious diseases and epidemics have revealed the shortcomings of existing diagnostics tools, and the necessity for further improvements. Optical biosensors can lay the foundations for future generation diagnostics by providing means to detect biomarkers in a highly sensitive, specific, quantitative and multiplexed fashion. Here, we review an optical sensing technology, Interferometric Reflectance Imaging Sensor (IRIS), and the relevant features of this multifunctional platform for quantitative, label-free and dynamic detection. We discuss two distinct modalities for IRIS: (i) low-magnification (ensemble biomolecular mass measurements) and (ii) high-magnification (digital detection of individual nanoparticles) along with their applications, including label-free detection of multiplexed protein chips, measurement of single nucleotide polymorphism, quantification of transcription factor DNA binding, and high sensitivity digital sensing and characterization of nanoparticles and viruses. PMID:26205273

Optical diagnostics in the oral cavity: an overview.

PubMed

Wilder-Smith, P; Holtzman, J; Epstein, J; Le, A

2010-11-01

As the emphasis shifts from damage mitigation to disease prevention or reversal of early disease in the oral cavity, the need for sensitive and accurate detection and diagnostic tools become more important. Many novel and emergent optical diagnostic modalities for the oral cavity are becoming available to clinicians with a variety of desirable attributes including: (i) non-invasiveness, (ii) absence of ionizing radiation, (iii) patient-friendliness, (iv) real-time information (v) repeatability, and (vi) high-resolution surface and subsurface images. In this article, the principles behind optical diagnostic approaches, their feasibility and applicability for imaging soft and hard tissues, and their potential usefulness as a tool in the diagnosis of oral mucosal lesions, dental pathologies, and other dental applications will be reviewed. The clinical applications of light-based imaging technologies in the oral cavity and of their derivative devices will be discussed to provide the reader with a comprehensive understanding of emergent diagnostic modalities. © 2010 John Wiley & Sons A/S.

A Comparison of Optical, Electrochemical, Magnetic, and Colorimetric Point-of-Care Biosensors for Infectious Disease Diagnosis.

PubMed

Pashchenko, Oleksandra; Shelby, Tyler; Banerjee, Tuhina; Santra, Santimukul

2018-06-18

Each year, infectious diseases are responsible for millions of deaths, most of which occur in the rural areas of developing countries. Many of the infectious disease diagnostic tools used today require a great deal of time, a laboratory setting, and trained personnel. Due to this, the need for effective point-of-care (POC) diagnostic tools is greatly increasing with an emphasis on affordability, portability, sensitivity, specificity, timeliness, and ease of use. In this Review, we discuss the various diagnostic modalities that have been utilized toward this end and are being further developed to create POC diagnostic technologies, and we focus on potential effectiveness in resource-limited settings. The main modalities discussed herein are optical-, electrochemical-, magnetic-, and colorimetric-based modalities utilized in diagnostic technologies for infectious diseases. Each of these modalities feature pros and cons when considering application in POC settings but, overall, reveal a promising outlook for the future of this field of technological development.

Prospective European-wide multicentre study on a blood based real-time PCR for the diagnosis of acute schistosomiasis.

PubMed

Wichmann, Dominic; Poppert, Sven; Von Thien, Heidrun; Clerinx, Joannes; Dieckmann, Sebastian; Jensenius, Mogens; Parola, Philippe; Richter, Joachim; Schunk, Mirjam; Stich, August; Zanger, Philipp; Burchard, Gerd D; Tannich, Egbert

2013-01-30

Acute schistosomiasis constitutes a rare but serious condition in individuals experiencing their first prepatent Schistosoma infection. To circumvent costly and time-consuming diagnostics, an early and rapid diagnosis is required. So far, classic diagnostic tools such as parasite microscopy or serology lack considerable sensitivity at this early stage of Schistosoma infection. To validate the use of a blood based real-time polymerase chain reaction (PCR) test for the detection of Schistosoma DNA in patients with acute schistosomiasis who acquired their infection in various endemic regions we conducted a European-wide prospective study in 11 centres specialized in travel medicine and tropical medicine. Patients with a history of recent travelling to schistosomiasis endemic regions and freshwater contacts, an episode of fever (body temperature ≥38.5°C) and an absolute or relative eosinophil count of ≥700/μl or 10%, were eligible for participation. PCR testing with DNA extracted from serum was compared with results from serology and microscopy. Of the 38 patients with acute schistosomiasis included into the study, PCR detected Schistosoma DNA in 35 patients at initial presentation (sensitivity 92%). In contrast, sensitivity of serology (enzyme immunoassay and/or immunofluorescence assay) or parasite microscopy was only 70% and 24%, respectively. For the early diagnosis of acute schistosomiasis, real-time PCR for the detection of schistosoma DNA in serum is more sensitive than classic diagnostic tools such as serology or microscopy, irrespective of the region of infection. Generalization of the results to all Schistosoma species may be difficult as in the study presented here only eggs of S. mansoni were detected by microscopy. A minimum amount of two millilitre of serum is required for sufficient diagnostic accuracy.

The Diagnostic Value of Gastrin-17 Detection in Atrophic Gastritis

PubMed Central

Wang, Xu; Ling, Li; Li, Shanshan; Qin, Guiping; Cui, Wei; Li, Xiang; Ni, Hong

2016-01-01

Abstract A meta-analysis was performed to assess the diagnostic value of gastrin-17 (G-17) for the early detection of chronic atrophic gastritis (CAG). An extensive literature search was performed, with the aim of selecting publications that reported the accuracy of G-17 in predicting CAG, in the following databases: PubMed, Science Direct, Web of Science, Chinese Biological Medicine, Chinese National Knowledge Infrastructure, Wanfang, and VIP. To assess the diagnostic value of G-17, the following statistics were estimated and described: sensitivity, specificity, diagnostic odds ratios (DOR), summary receiver operating characteristic curves, area under the curve (AUC), and 95% confidence intervals (CIs). Thirteen studies that met the inclusion criteria were included in this meta-analysis, comprising 894 patients and 1950 controls. The pooled sensitivity and specificity of these studies were 0.48 (95% CI: 0.45–0.51) and 0.79 (95% CI: 0.77–0.81), respectively. The DOR was 5.93 (95% CI: 2.93–11.99), and the AUC was 0.82. G-17 may have potential diagnostic value because it has good specificity and a moderate DOR and AUC for CAG. However, more studies are needed to improve the sensitivity of this diagnostic tool in the future. PMID:27149493

Extended Testability Analysis Tool

NASA Technical Reports Server (NTRS)

Melcher, Kevin; Maul, William A.; Fulton, Christopher

2012-01-01

The Extended Testability Analysis (ETA) Tool is a software application that supports fault management (FM) by performing testability analyses on the fault propagation model of a given system. Fault management includes the prevention of faults through robust design margins and quality assurance methods, or the mitigation of system failures. Fault management requires an understanding of the system design and operation, potential failure mechanisms within the system, and the propagation of those potential failures through the system. The purpose of the ETA Tool software is to process the testability analysis results from a commercial software program called TEAMS Designer in order to provide a detailed set of diagnostic assessment reports. The ETA Tool is a command-line process with several user-selectable report output options. The ETA Tool also extends the COTS testability analysis and enables variation studies with sensor sensitivity impacts on system diagnostics and component isolation using a single testability output. The ETA Tool can also provide extended analyses from a single set of testability output files. The following analysis reports are available to the user: (1) the Detectability Report provides a breakdown of how each tested failure mode was detected, (2) the Test Utilization Report identifies all the failure modes that each test detects, (3) the Failure Mode Isolation Report demonstrates the system s ability to discriminate between failure modes, (4) the Component Isolation Report demonstrates the system s ability to discriminate between failure modes relative to the components containing the failure modes, (5) the Sensor Sensor Sensitivity Analysis Report shows the diagnostic impact due to loss of sensor information, and (6) the Effect Mapping Report identifies failure modes that result in specified system-level effects.

Use of a Process Analysis Tool for Diagnostic Study on Fine Particulate Matter Predictions in the U.S.-Part II: Analysis and Sensitivity Simulations

EPA Science Inventory

Following the Part I paper that described an application of the U.S. EPA Models-3/Community Multiscale Air Quality (CMAQ) modeling system to the 1999 Southern Oxidants Study episode, this paper presents results from process analysis (PA) using the PA tool embedded in CMAQ and s...

A novel molecular diagnostic tool for improved sensitivity and reliability detection of “Candidatus Liberibacter asiaticus”, bacterium associated with huanglongbing (HLB) bacterium Candidatus Liberibacter.

USDA-ARS?s Scientific Manuscript database

Sensitive and accurate detection is a prerequisite for efficient management and regulatory responses to prevent the introduction and spread of HLB-associated “Candidatus Liberibacter species to unaffected areas. To improve the current detection limit of HLB-associated “Ca. Liberibacter” spp, we deve...

Polymeric nanoparticles for optical sensing.

PubMed

Canfarotta, Francesco; Whitcombe, Michael J; Piletsky, Sergey A

2013-12-01

Nanotechnology is a powerful tool for use in diagnostic applications. For these purposes a variety of functional nanoparticles containing fluorescent labels, gold and quantum dots at their cores have been produced, with the aim of enhanced sensitivity and multiplexing capabilities. This work will review progress in the application of polymeric nanoparticles in optical diagnostics, both for in vitro and in vivo detection, together with a discussion of their biodistribution and biocompatibility. © 2013.

Profile of children with urinary tract infection and the utility of urine dipstick as a diagnostic tool.

PubMed

Ojha, A R; Aryal, U R

2014-01-01

Urinary tract infection is a common problem in children and its early diagnosis and treatment is important to prevent long-term complications. Urine dipstick can be an important tool in this respect. The aim of this study is to look at the utility of urine dipstick as a diagnostic tool for UTI and will also see the clinical profile of children with UTI and sensitivity pattern of antibiotics among the isolates of urine culture. Urine samples of all children below 14 years of age who were suspected of urinary tract infection were sent for routine microscopic examination and dipstick testing. Urine culture and sensitivity were sent for those samples that were tested positive for nitrite, leucocyte esterase activity or both. For every fifth sample, which is dipstick negative, a culture and sensitivity testing was done. Among 110 children enrolled, 32(29%) cases had significant bacteriuria. Out of 32 culture positive cases 18(56%) were female. Fever was the main complaint (62.5%)). Escherichia Coli was isolated in 81.25% of cases. Amikacin was sensitive in 93% and amoxicillinwas resistant in 82%. The sensitivity, specificity, positive predictive value, negative predictive value of nitrite test was 65%, 80%, 58%, 85% respectively; those of leucocyte esterase are 84%, 55%, 43%, 89% respectively; those for significant microscopic pyuria >10/hpf were 65%, 74%, 51%, 84% respectively. E. Coli is the commonest uropathogen in children with UTI. Amikacin is the most sensitive antibiotic against all the isolates. A positive dipstick both for nitrite and leucocyte esterase is associated with high sensitivity and specificity for urinary tract infection as compared to either of them positive alone. In addition, urine WBC ≥10/hpf is associated with high probability of UTI.

Computational diagnosis of canine lymphoma

NASA Astrophysics Data System (ADS)

Mirkes, E. M.; Alexandrakis, I.; Slater, K.; Tuli, R.; Gorban, A. N.

2014-03-01

One out of four dogs will develop cancer in their lifetime and 20% of those will be lymphoma cases. PetScreen developed a lymphoma blood test using serum samples collected from several veterinary practices. The samples were fractionated and analysed by mass spectrometry. Two protein peaks, with the highest diagnostic power, were selected and further identified as acute phase proteins, C-Reactive Protein and Haptoglobin. Data mining methods were then applied to the collected data for the development of an online computer-assisted veterinary diagnostic tool. The generated software can be used as a diagnostic, monitoring and screening tool. Initially, the diagnosis of lymphoma was formulated as a classification problem and then later refined as a lymphoma risk estimation. Three methods, decision trees, kNN and probability density evaluation, were used for classification and risk estimation and several preprocessing approaches were implemented to create the diagnostic system. For the differential diagnosis the best solution gave a sensitivity and specificity of 83.5% and 77%, respectively (using three input features, CRP, Haptoglobin and standard clinical symptom). For the screening task, the decision tree method provided the best result, with sensitivity and specificity of 81.4% and >99%, respectively (using the same input features). Furthermore, the development and application of new techniques for the generation of risk maps allowed their user-friendly visualization.

FNA diagnostic value in patients with neck masses in two teaching hospitals in Iran.

PubMed

Saatian, Minoo; Badie, Banafsheh Moradmand; Shahriari, Sogol; Fattahi, Fahimeh; Rasoolinejad, Mehrnaz

2011-01-01

The FNA (fine needle aspiration) procedure is simple, inexpensive, available and a safe method for the diagnosis of a neck mass. FNA has numerous advantages over open surgical biopsies as an initial diagnostic tool; therefore we decided to compare the accuracy of this method with open biopsy. This retrospective as well as descriptive study comparing preoperative FNA results with existing data in the Pathology Department in Bu-Ali and Amir Alam Hospitals. Our study included 100 patients with neck masses of which 22 were thyroid masses, 31 were salivary gland masses, and 47 were other masses. Age ranged from 3 years to 80 years with the mean age of 42.6 years. There were 59 men and 41 women. The Sensitivity was 72%, Specificity 87%, PPV 85%, NPV 75% and diagnostic Accuracy 79%. In this study we had also 26% false negative and 15% false positive. FNA is a valuable diagnostic tool in the management of neck masses; also it has been used for staging and planning of treatment for the wide and metastatic malignancy. This technique reduces the need for more invasive and costly procedures. According to the high sensitivity and high accuracy in this study, FNA can be used as the first step of diagnoses test in neck masses.

Replication and Comparison of the Newly Proposed ADOS-2, Module 4 Algorithm in ASD Without ID: A Multi-site Study.

PubMed

Pugliese, Cara E; Kenworthy, Lauren; Bal, Vanessa Hus; Wallace, Gregory L; Yerys, Benjamin E; Maddox, Brenna B; White, Susan W; Popal, Haroon; Armour, Anna Chelsea; Miller, Judith; Herrington, John D; Schultz, Robert T; Martin, Alex; Anthony, Laura Gutermuth

2015-12-01

Recent updates have been proposed to the Autism Diagnostic Observation Schedule-2 Module 4 diagnostic algorithm. This new algorithm, however, has not yet been validated in an independent sample without intellectual disability (ID). This multi-site study compared the original and revised algorithms in individuals with ASD without ID. The revised algorithm demonstrated increased sensitivity, but lower specificity in the overall sample. Estimates were highest for females, individuals with a verbal IQ below 85 or above 115, and ages 16 and older. Best practice diagnostic procedures should include the Module 4 in conjunction with other assessment tools. Balancing needs for sensitivity and specificity depending on the purpose of assessment (e.g., clinical vs. research) and demographic characteristics mentioned above will enhance its utility.

Use of bacteriophage cell wall-binding proteins for rapid diagnostics of Listeria.

PubMed

Schmelcher, Mathias; Loessner, Martin J

2014-01-01

Diagnostic protocols for food-borne bacterial pathogens such as Listeria need to be sensitive, specific, rapid, and inexpensive. Conventional culture methods are hampered by lengthy enrichment and incubation steps. Bacteriophage-derived high-affinity binding molecules (cell wall-binding domains, CBDs) specific for Listeria cells have recently been introduced as tools for detection and differentiation of this pathogen in foods. When coupled with magnetic separation, these proteins offer advantages in sensitivity and speed compared to the standard diagnostic methods. Furthermore, fusion of CBDs to differently colored fluorescent reporter proteins enables differentiation of Listeria strains in mixed cultures. This chapter provides protocols for detection of Listeria in food by CBD-based magnetic separation and subsequent multiplexed identification of strains of different serotypes with reporter-CBD fusion proteins.

PIVKA-II is a useful tool for diagnostic characterization of ultrasound-detected liver nodules in cirrhotic patients

PubMed Central

Saitta, Carlo; Raffa, Giuseppina; Alibrandi, Angela; Brancatelli, Santa; Lombardo, Daniele; Tripodi, Gianluca; Raimondo, Giovanni; Pollicino, Teresa

2017-01-01

Abstract Protein induced by vitamin K absence-II (PIVKA-II) is a potential screening marker for hepatocellular carcinoma (HCC). Limited data are available about its utility in discriminating neoplastic from regenerative nodules at ultrasonography (US) evaluation in cirrhotic patients. Aim of this study was to investigate the diagnostic utility of PIVKA-II in cases showing liver nodules of uncertain diagnosis at US. Ninety cirrhotics with US evidence of liver nodule(s) were enrolled. All patients underwent blood sampling within 1 week of US and were thereafter followed up. HCC was confirmed in 40/90 cases, and in all cases it was in a very early/early stage. All sera were tested for PIVKA-II and alpha-fetoprotein (AFP) at the end of follow-up. PIVKA-II at a cut off of 60 mAU/mL was significantly associated with HCC at both univariate and multivariate analysis (P = .016 and P = .032, respectively). AFP at a cut off of 6.5 ng/mL was not associated with HCC at univariate analysis (P = .246). ROC curves showed that PIVKA-II had 60% sensitivity, 88% specificity, 80% positive predictive value (PPV), and 73% negative predictive value (NPV), whereas AFP had 67% sensitivity, 68% specificity, 63% PPV, and 72% NPV. AUROC curves showed that the combination of both biomarkers increased the diagnostic accuracy for HCC (AUC 0.76; sensitivity 70%, specificity 94%, PPV 91%, and NPV 79%). In conclusion, PIVKA-II is a useful tool for the diagnostic definition of US-detected liver nodules in cirrhotic patients, and it provides high diagnostic accuracy for HCC when combined with AFP. PMID:28658121

Indications requiring preoperative magnetic resonance imaging before knee arthroscopy.

PubMed

Roßbach, Björn Peter; Pietschmann, Matthias Frank; Gülecyüz, Mehmet Fatih; Niethammer, Thomas Richard; Ficklscherer, Andreas; Wild, Stefan; Jansson, Volkmar; Müller, Peter Ernst

2014-12-22

Knee arthroscopy knee is gold standard in diagnosis and simultaneous treatment of knee disorders. But most patients undergo magnetic resonance imaging (MRI) before arthroscopy, although MRI results are not always consistent with arthroscopic findings. This raises the question in which suspected diagnoses MRI really has influence on diagnosis and consecutive surgical therapy. Preoperative MRI of 330 patients with knee disorders were compared with arthroscopic findings. The MRI were performed by 23 radiologists without specialization in musculoskeletal diagnostics. Specificity, sensitivity, negative/positive predictive value and accuracy of MRI were calculated in comparison to arthroscopic findings. We found sensitivity/specificity of 58%/93% for anterior horn, 94%/46% for posterior horn of medial meniscus and 71%/81% for anterior and 62%/82% for posterior horn of lateral meniscus. Related to anterior cruciate ligament injuries we showed sensitivity/specificity of 82%/91% for grade 0 + I and 72%/96% for grade II + III. For Cartilage damage sensitivity/specificity of 98%/7% for grade I-, 89%/29% for grade II-, 96%/38% for grade III- and 96%/69% for grade IV-lesions were revealed. The MRI should not be used as routine diagnostic tool for knee pain. No relevant information for meniscal lesions and anterior cruciate ligament ruptures has been gained with MRI from non-specialized outside imaging centres. The MRI should not be used as routine diagnostic tool for knee pain. No relevant information for meniscal lesions and anterior cruciate ligament ruptures has been gained with MRI from non-specialized outside imaging centres.

MOLECULAR DIAGNOSTICS - ANOTHER PIECE IN THE ENVIRONMENTAL PUZZLE

EPA Science Inventory

Molecular biology offers sensitive and expedient tools for the detection of exposure to environmental stressors. Molecular approaches provide the means for detection of the "first cellular event(s)" in response to environmental changes-specifically, immediate changes in gene expr...

The diagnostic value of troponin in critically ill.

PubMed

Voga, Gorazd

2010-01-01

Troponin T and I are sensitive and specific markers of myocardial necrosis. They are used for the routine diagnosis of acute coronary syndrome. In critically ill patients they are basic diagnostic tool for diagnosis of myocardial necrosis due to myocardial ischemia. Moreover, the increase of troponin I and T is related with adverse outcome in many subgroups of critically ill patients. The new, high sensitivity tests which have been developed recently allow earlier and more accurate diagnosis of acute coronary syndrome. The use of the new tests has not been studied in critically ill patients, but they will probably replace the old tests and will be used on the routine basis.

Comparative Evaluation of Bivalent Malaria Rapid Diagnostic Tests versus Traditional Methods in Field with Special Reference to Heat Stability Testing in Central India

PubMed Central

Singh, Neeru; Bharti, Praveen K.; Singh, Mrigendra P.; Mishra, Sweta; Shukla, Man M.; Sharma, Ravendra K.; Singh, Rajesh K.

2013-01-01

Background Malaria presents a diagnostic challenge in areas where both Plasmodium falciparum and P.vivax are co-endemic. Bivalent Rapid Diagnostic tests (RDTs) showed promise as diagnostic tools for P.falciparum and P.vivax. To assist national malaria control programme in the selection of RDTs, commercially available seven malaria RDTs were evaluated in terms of their performance with special reference to heat stability. Methodology/Principal Findings This study was undertaken in four forested districts of central India (July, 2011– March, 2012). All RDTs were tested simultaneously in field along with microscopy as gold standard. These RDTs were stored in their original packing at 25°C before transport to the field or they were stored at 35°C and 45°C upto 100 days for testing the performance of RDTs at high temperature. In all 2841 patients with fever were screened for malaria of which 26% were positive for P.falciparum, and 17% for P.vivax. The highest sensitivity of any RDT for P.falciparum was 98% (95% CI; 95.9–98.8) and lowest sensitivity was 76% (95% CI; 71.7–79.6). For P.vivax highest and lowest sensitivity for any RDT was 80% (95% CI; 94.9 - 83.9) and 20% (95% CI; 15.6–24.5) respectively. Heat stability experiments showed that most RDTs for P.falciparum showed high sensitivity at 45°C upto 90 days. While for P.vivax only two RDTs maintained good sensitivity upto day 90 when compared with RDTs kept at room temperature. Agreement between observers was excellent for positive and negative readings for both P.falciparum and P.vivax (Kappa >0.6–0.9). Conclusion This is first field evaluation of RDTs regarding their temperature stability. Although RDTs are useful as diagnostic tool for P.falciparum and P.vivax even at high temperature, the quality of RDTs should be regulated and monitored more closely. PMID:23472135

An electronic screen for triaging adolescent substance use by risk levels.

PubMed

Levy, Sharon; Weiss, Roger; Sherritt, Lon; Ziemnik, Rosemary; Spalding, Allegra; Van Hook, Shari; Shrier, Lydia A

2014-09-01

Screening adolescents for substance use and intervening immediately can reduce the burden of addiction and substance-related morbidity. Several screening tools have been developed to identify problem substance use for adolescents, but none have been calibrated to triage adolescents into clinically relevant risk categories to guide interventions. To describe the psychometric properties of an electronic screen and brief assessment tool that triages adolescents into 4 actionable categories regarding their experience with nontobacco substance use. Adolescent patients (age range, 12-17 years) arriving for routine medical care at 2 outpatient primary care centers and 1 outpatient center for substance use treatment at a pediatric hospital completed an electronic screening tool from June 1, 2012, through March 31, 2013, that consisted of a question on the frequency of using 8 types of drugs in the past year (Screening to Brief Intervention). Additional questions assessed severity of any past-year substance use. Patients completed a structured diagnostic interview (Composite International Diagnostic Interview-Substance Abuse Module), yielding Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) substance use diagnoses. For the entire screen and the Screening to Brief Intervention, sensitivity and specificity for identifying nontobacco substance use, substance use disorders, severe substance use disorders, and tobacco dependence were calculated using the Composite International Diagnostic Interview-Substance Abuse Module as the criterion standard. Of 340 patients invited to participate, 216 (63.5%) enrolled in the study. Sensitivity and specificity were 100% and 84% (95% CI, 76%-89%) for identifying nontobacco substance use, 90% (95% CI, 77%-96%) and 94% (95% CI, 89%-96%) for substance use disorders, 100% and 94% (95% CI, 90%-96%) for severe substance use disorders, and 75% (95% CI, 52%-89%) and 98% (95% CI, 95%-100%) for nicotine dependence. No significant differences were found in sensitivity or specificity between the full tool and the Screening to Brief Intervention. A single screening question assessing past-year frequency use for 8 commonly misused categories of substances appears to be a valid method for discriminating among clinically relevant risk categories of adolescent substance use.

An Electronic Screen for Triaging Adolescent Substance Use by Risk Levels

PubMed Central

Levy, Sharon; Weiss, Roger; Sherritt, Lon; Ziemnik, Rosemary; Spalding, Allegra; Van Hook, Shari; Shrier, Lydia A.

2014-01-01

IMPORTANCE Screening adolescents for substance use and intervening immediately can reduce the burden of addiction and substance-related morbidity. Several screening tools have been developed to identify problem substance use for adolescents, but none have been calibrated to triage adolescents into clinically relevant risk categories to guide interventions. OBJECTIVE To describe the psychometric properties of an electronic screen and brief assessment tool that triages adolescents into 4 actionable categories regarding their experience with nontobacco substance use. DESIGN, SETTING, AND PARTICIPANTS Adolescent patients (age range, 12–17 years) arriving for routine medical care at 2 outpatient primary care centers and 1 outpatient center for substance use treatment at a pediatric hospital completed an electronic screening tool from June 1, 2012, through March 31, 2013, that consisted of a question on the frequency of using 8 types of drugs in the past year (Screening to Brief Intervention). Additional questions assessed severity of any past-year substance use. Patients completed a structured diagnostic interview (Composite International Diagnostic Interview–Substance Abuse Module), yielding Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) substance use diagnoses. MAIN OUTCOMES AND MEASURES For the entire screen and the Screening to Brief Intervention, sensitivity and specificity for identifying nontobacco substance use, substance use disorders, severe substance use disorders, and tobacco dependence were calculated using the Composite International Diagnostic Interview–Substance Abuse Module as the criterion standard. RESULTS Of 340 patients invited to participate, 216 (63.5%) enrolled in the study. Sensitivity and specificity were 100% and 84%(95%CI, 76%–89%) for identifying nontobacco substance use, 90% (95%CI, 77%–96%) and 94%(95%CI, 89%–96%) for substance use disorders, 100% and 94%(95%CI, 90%–96%) for severe substance use disorders, and 75% (95%CI, 52%–89%) and 98%(95%CI, 95%–100%) for nicotine dependence. No significant differences were found in sensitivity or specificity between the full tool and the Screening to Brief Intervention. CONCLUSIONS AND RELEVANCE A single screening question assessing past-year frequency use for 8 commonly misused categories of substances appears to be a valid method for discriminating among clinically relevant risk categories of adolescent substance use. PMID:25070067

Diagnostic tools for identifying sleepy drivers in the field.

DOT National Transportation Integrated Search

2013-05-06

The overarching goal of this project was to identify and evaluate cognitive and behavioral indices that are sensitive to sleep : deprivation and may help identify commercial motor vehicle drivers (CMV) who are at-risk for driving in a sleep deprived ...

Comparative Capabilities of Clinical Assessment, Diagnostic Criteria, and Polysomnography in Detecting Sleep Bruxism

PubMed Central

Palinkas, Marcelo; De Luca Canto, Graziela; Rodrigues, Laíse Angélica Mendes; Bataglion, César; Siéssere, Selma; Semprini, Marisa; Regalo, Simone Cecilio Hallak

2015-01-01

Objective: To evaluate the diagnostic capability of signs and symptoms of sleep bruxism (SB) as per the American Academy of Sleep Medicine (AASM) criteria and a diagnostic grading system proposed by international experts for assessing SB. Methods: The study was conducted in three phases (interview, physical examination, and sleep studies). Subjects were asked about self-reported tooth grinding sounds occurring during sleep, muscle fatigue, temporal headaches, jaw muscle pain, and jaw locking. A visual examination was conducted to check for presence of abnormal tooth wear. A full-night polysomnography (PSG) was performed. After three phases, the subjects were divided into two groups matched by age and gender: Case Group, 45 SB subjects, and Control Group, 45 non-SB subjects. Diagnostic accuracy measurements were calculated for each sign or symptom individually and for the two diagnostic criteria analyzed. Results: Muscle fatigue, temporal headaches, and AASM criteria were associated with highest sensitivity (78%, 67%, 58%, respectively) and also with highest diagnostic odds ratio (OR = 9.63, 9.25, 6.33, respectively). Jaw locking, muscle pain, and the criterion of “probable SB” were associated with the worst sensitivity (16%, 18%, 22%, respectively). Conclusions: Presence of muscle fatigue and temporal headaches can be considered good tools to screen SB patients. None of the diagnostic criteria evaluated was able to accurately identify patients with SB. AASM criteria had the strongest diagnostic capabilities and—although they do not attain diagnostic values high enough to replace the current gold standard (PSG)—should be used as a screening tool to identify SB. Citation: Palinkas M, De Luca Canto G, Rodrigues LA, Bataglion C, Siéssere S, Semprini M, Regalo SC. Comparative capabilities of clinical assessment, diagnostic criteria, and polysomnography in detecting sleep bruxism. J Clin Sleep Med 2015;11(11):1319–1325. PMID:26235152

The diagnostic value of polymerase chain reaction for Mycobacterium tuberculosis to distinguish intestinal tuberculosis from crohn's disease: A meta-analysis.

PubMed

Jin, Ting; Fei, Baoying; Zhang, Yu; He, Xujun

2017-01-01

Intestinal tuberculosis (ITB) and Crohn's disease (CD) are important differential diagnoses that can be difficult to distinguish. Polymerase chain reaction (PCR) for Mycobacterium tuberculosis (MTB) is an efficient and promising tool. This meta-analysis was performed to systematically and objectively assess the potential diagnostic accuracy and clinical value of PCR for MTB in distinguishing ITB from CD. We searched PubMed, Embase, Web of Science, Science Direct, and the Cochrane Library for eligible studies, and nine articles with 12 groups of data were identified. The included studies were subjected to quality assessment using the revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. The summary estimates were as follows: sensitivity 0.47 (95% CI: 0.42-0.51); specificity 0.95 (95% CI: 0.93-0.97); the positive likelihood ratio (PLR) 10.68 (95% CI: 6.98-16.35); the negative likelihood ratio (NLR) 0.49 (95% CI: 0.33-0.71); and diagnostic odds ratio (DOR) 21.92 (95% CI: 13.17-36.48). The area under the curve (AUC) was 0.9311, with a Q* value of 0.8664. Heterogeneity was found in the NLR. The heterogeneity of the studies was evaluated by meta-regression analysis and subgroup analysis. The current evidence suggests that PCR for MTB is a promising and highly specific diagnostic method to distinguish ITB from CD. However, physicians should also keep in mind that negative results cannot exclude ITB for its low sensitivity. Additional prospective studies are needed to further evaluate the diagnostic accuracy of PCR.

Diagnostic methods for assessing maxillary skeletal and dental transverse deficiencies: A systematic review

PubMed Central

Sawchuk, Dena; Currie, Kris; Vich, Manuel Lagravere; Palomo, Juan Martin

2016-01-01

Objective To evaluate the accuracy and reliability of the diagnostic tools available for assessing maxillary transverse deficiencies. Methods An electronic search of three databases was performed from their date of establishment to April 2015, with manual searching of reference lists of relevant articles. Articles were considered for inclusion if they reported the accuracy or reliability of a diagnostic method or evaluation technique for maxillary transverse dimensions in mixed or permanent dentitions. Risk of bias was assessed in the included articles, using the Quality Assessment of Diagnostic Accuracy Studies tool-2. Results Nine articles were selected. The studies were heterogeneous, with moderate to low methodological quality, and all had a high risk of bias. Four suggested that the use of arch width prediction indices with dental cast measurements is unreliable for use in diagnosis. Frontal cephalograms derived from cone-beam computed tomography (CBCT) images were reportedly more reliable for assessing intermaxillary transverse discrepancies than posteroanterior cephalograms. Two studies proposed new three-dimensional transverse analyses with CBCT images that were reportedly reliable, but have not been validated for clinical sensitivity or specificity. No studies reported sensitivity, specificity, positive or negative predictive values or likelihood ratios, or ROC curves of the methods for the diagnosis of transverse deficiencies. Conclusions Current evidence does not enable solid conclusions to be drawn, owing to a lack of reliable high quality diagnostic studies evaluating maxillary transverse deficiencies. CBCT images are reportedly more reliable for diagnosis, but further validation is required to confirm CBCT's accuracy and diagnostic superiority. PMID:27668196

Research gaps for three main tropical diseases in the People’s Republic of China

PubMed Central

2013-01-01

This scoping review analyzes the research gaps of three diseases: schistosomiasis japonica, malaria and echinococcosis. Based on available data in the P.R. China, we highlight the gaps between control capacity and prevalence levels, and between diagnostic/drug development and population need for treatment at different stages of the national control programme. After reviewing the literature from 848 original studies and consultations with experts in the field, the gaps were identified as follows. Firstly, the malaria research gaps include (i) deficiency of active testing in the public community and no appropriate technique to evaluate elimination, (ii) lack of sensitive diagnostic tools for asymptomatic patients, (iii) lack of safe drugs for mass administration. Secondly, gaps in research of schistosomiasis include (i) incongruent policy in the implementation of integrated control strategy for schistosomiasis, (ii) lack of effective tools for Oncomelania sp. snail control, (iii) lack of a more sensitive and cheaper diagnostic test for large population samples, (iv) lack of new drugs in addition to praziquantel. Thirdly, gaps in research of echinococcosis include (i) low capacity in field epidemiology studies, (ii) lack of sanitation improvement studies in epidemic areas, (iii) lack of a sensitivity test for early diagnosis, (iv) lack of more effective drugs for short-term treatment. We believe these three diseases can eventually be eliminated in mainland China if all the research gaps are abridged in a short period of time. PMID:23895635

Development and Validation of a Natural Language Processing Tool to Identify Patients Treated for Pneumonia across VA Emergency Departments.

PubMed

Jones, B E; South, B R; Shao, Y; Lu, C C; Leng, J; Sauer, B C; Gundlapalli, A V; Samore, M H; Zeng, Q

2018-01-01

Identifying pneumonia using diagnosis codes alone may be insufficient for research on clinical decision making. Natural language processing (NLP) may enable the inclusion of cases missed by diagnosis codes. This article (1) develops a NLP tool that identifies the clinical assertion of pneumonia from physician emergency department (ED) notes, and (2) compares classification methods using diagnosis codes versus NLP against a gold standard of manual chart review to identify patients initially treated for pneumonia. Among a national population of ED visits occurring between 2006 and 2012 across the Veterans Affairs health system, we extracted 811 physician documents containing search terms for pneumonia for training, and 100 random documents for validation. Two reviewers annotated span- and document-level classifications of the clinical assertion of pneumonia. An NLP tool using a support vector machine was trained on the enriched documents. We extracted diagnosis codes assigned in the ED and upon hospital discharge and calculated performance characteristics for diagnosis codes, NLP, and NLP plus diagnosis codes against manual review in training and validation sets. Among the training documents, 51% contained clinical assertions of pneumonia; in the validation set, 9% were classified with pneumonia, of which 100% contained pneumonia search terms. After enriching with search terms, the NLP system alone demonstrated a recall/sensitivity of 0.72 (training) and 0.55 (validation), and a precision/positive predictive value (PPV) of 0.89 (training) and 0.71 (validation). ED-assigned diagnostic codes demonstrated lower recall/sensitivity (0.48 and 0.44) but higher precision/PPV (0.95 in training, 1.0 in validation); the NLP system identified more "possible-treated" cases than diagnostic coding. An approach combining NLP and ED-assigned diagnostic coding classification achieved the best performance (sensitivity 0.89 and PPV 0.80). System-wide application of NLP to clinical text can increase capture of initial diagnostic hypotheses, an important inclusion when studying diagnosis and clinical decision-making under uncertainty. Schattauer GmbH Stuttgart.

Accuracy of Brief Screening Tools for Identifying Postpartum Depression Among Adolescent Mothers

PubMed Central

Venkatesh, Kartik K.; Zlotnick, Caron; Triche, Elizabeth W.; Ware, Crystal

2014-01-01

OBJECTIVE: To evaluate the accuracy of the Edinburgh Postnatal Depression Scale (EPDS) and 3 subscales for identifying postpartum depression among primiparous adolescent mothers. METHODS: Mothers enrolled in a randomized controlled trial to prevent postpartum depression completed a psychiatric diagnostic interview and the 10-item EPDS at 6 weeks, 3 months, and 6 months postpartum. Three subscales of the EPDS were assessed as brief screening tools: 3-item anxiety subscale (EPDS-3), 7-item depressive symptoms subscale (EPDS-7), and 2-item subscale (EPDS-2) that resemble the Patient Health Questionnaire-2. Receiver operating characteristic curves and the areas under the curves for each tool were compared to assess accuracy. The sensitivities and specificities of each screening tool were calculated in comparison with diagnostic criteria for a major depressive disorder. Repeated-measures longitudinal analytical techniques were used. RESULTS: A total of 106 women contributed 289 postpartum visits; 18% of the women met criteria for incident postpartum depression by psychiatric diagnostic interview. When used as continuous measures, the full EPDS, EPDS-7, and EPDS-2 performed equally well (area under the curve >0.9). Optimal cutoff scores for a positive depression screen for the EPDS and EPDS-7 were lower (≥9 and ≥7, respectively) than currently recommended cutoff scores (≥10). At optimal cutoff scores, the EPDS and EPDS-7 both had sensitivities of 90% and specificities of >85%. CONCLUSIONS: The EPDS, EPDS-7, and EPDS-2 are highly accurate at identifying postpartum depression among adolescent mothers. In primary care pediatric settings, the EPDS and its shorter subscales have potential for use as effective depression screening tools. PMID:24344102

Replication and Comparison of the Newly Proposed ADOS-2, Module 4 Algorithm in ASD without ID: A Multi-site Study

PubMed Central

Pugliese, Cara E.; Kenworthy, Lauren; Bal, Vanessa Hus; Wallace, Gregory L; Yerys, Benjamin E; Maddox, Brenna B.; White, Susan W.; Popal, Haroon; Armour, Anna Chelsea; Miller, Judith; Herrington, John D.; Schultz, Robert T.; Martin, Alex; Anthony, Laura Gutermuth

2015-01-01

Recent updates have been proposed to the Autism Diagnostic Observation Schedule-2 Module 4 diagnostic algorithm. This new algorithm, however, has not yet been validated in an independent sample without intellectual disability (ID). This multi-site study compared the original and revised algorithms in individuals with ASD without ID. The revised algorithm demonstrated increased sensitivity, but lower specificity in the overall sample. Estimates were highest for females, individuals with a verbal IQ below 85 or above 115, and ages 16 and older. Best practice diagnostic procedures should include the Module 4 in conjunction with other assessment tools. Balancing needs for sensitivity and specificity depending on the purpose of assessment (e.g., clinical vs. research) and demographic characteristics mentioned above will enhance its utility. PMID:26385796

ADC as a useful diagnostic tool for differentiating benign and malignant vertebral bone marrow lesions and compression fractures: a systematic review and meta-analysis.

PubMed

Suh, Chong Hyun; Yun, Seong Jong; Jin, Wook; Lee, Sun Hwa; Park, So Young; Ryu, Chang-Woo

2018-07-01

To assess the sensitivity and specificity of quantitative assessment of the apparent diffusion coefficient (ADC) for differentiating benign and malignant vertebral bone marrow lesions (BMLs) and compression fractures (CFs) METHODS: An electronic literature search of MEDLINE and EMBASE was conducted. Bivariate modelling and hierarchical summary receiver operating characteristic modelling were performed to evaluate the diagnostic performance of ADC for differentiating vertebral BMLs. Subgroup analysis was performed for differentiating benign and malignant vertebral CFs. Meta-regression analyses according to subject, study and diffusion-weighted imaging (DWI) characteristics were performed. Twelve eligible studies (748 lesions, 661 patients) were included. The ADC exhibited a pooled sensitivity of 0.89 (95% confidence interval [CI] 0.80-0.94) and a pooled specificity of 0.87 (95% CI 0.78-0.93) for differentiating benign and malignant vertebral BMLs. In addition, the pooled sensitivity and specificity for differentiating benign and malignant CFs were 0.92 (95% CI 0.82-0.97) and 0.91 (95% CI 0.87-0.94), respectively. In the meta-regression analysis, the DWI slice thickness was a significant factor affecting heterogeneity (p < 0.01); thinner slice thickness (< 5 mm) showed higher specificity (95%) than thicker slice thickness (81%). Quantitative assessment of ADC is a useful diagnostic tool for differentiating benign and malignant vertebral BMLs and CFs. • Quantitative assessment of ADC is useful in differentiating vertebral BMLs. • Quantitative ADC assessment for BMLs had sensitivity of 89%, specificity of 87%. • Quantitative ADC assessment for CFs had sensitivity of 92%, specificity of 91%. • The specificity is highest (95%) with thinner (< 5 mm) DWI slice thickness.

Streptococcus A in paediatric accident and emergency: are rapid streptococcal tests and clinical examination of any help?

PubMed

Van Limbergen, J; Kalima, P; Taheri, S; Beattie, T F

2006-01-01

Rapid streptococcal tests (RSTs) for streptococcal pharyngitis have made diagnosis at once simpler and more complicated. The American Academy of Pediatrics recommends that all RSTs be confirmed by a follow up throat culture unless local validation has proved the RST to be equally sensitive. To evaluate (a) RST as a single diagnostic tool, compared with RST with or without throat culture; (b) clinical diagnosis and the relative contribution of different symptoms. The study included 213 patients with clinical signs of pharyngitis. Throat swabs were analysed using Quickvue+ Strep A Test; negative RSTs were backed up by throat culture. Thirteen clinical features commonly associated with strep throat were analysed using backward stepwise logistic regression. Positive results (RST or throat culture) were obtained in 33 patients; RST correctly identified 21. Eleven samples were false negative on RST. At a strep throat prevalence of 15.9%, sensitivity of RST was 65.6% (95% CI 46.8% to 81.4%) and specificity 99.4% (96.7% to 99.9%). Sensitivity of clinical diagnosis alone was 57% (34% to 78%) and specificity 71% (61% to 80%). Clinically, only history of sore throat, rash, and pyrexia contributed to the diagnosis of strep throat (p<0.05). The high specificity of RST facilitates early diagnosis of strep throat. However, the low sensitivity of RST does not support its use as a single diagnostic tool. The sensitivity in the present study is markedly different from that reported by the manufacturer. Clinical examination is of limited value in the diagnosis of strep throat. It is important to audit the performance of new diagnostic tests, previously validated in different settings.

Streptococcus A in paediatric accident and emergency: are rapid streptococcal tests and clinical examination of any help?

PubMed Central

Van Limbergen, J; Kalima, P; Taheri, S; Beattie, T F

2006-01-01

Background Rapid streptococcal tests (RSTs) for streptococcal pharyngitis have made diagnosis at once simpler and more complicated. The American Academy of Pediatrics recommends that all RSTs be confirmed by a follow up throat culture unless local validation has proved the RST to be equally sensitive. Aims To evaluate (a) RST as a single diagnostic tool, compared with RST with or without throat culture; (b) clinical diagnosis and the relative contribution of different symptoms. Methods The study included 213 patients with clinical signs of pharyngitis. Throat swabs were analysed using Quickvue+ Strep A Test; negative RSTs were backed up by throat culture. Thirteen clinical features commonly associated with strep throat were analysed using backward stepwise logistic regression. Results Positive results (RST or throat culture) were obtained in 33 patients; RST correctly identified 21. Eleven samples were false negative on RST. At a strep throat prevalence of 15.9%, sensitivity of RST was 65.6% (95% CI 46.8% to 81.4%) and specificity 99.4% (96.7% to 99.9%). Sensitivity of clinical diagnosis alone was 57% (34% to 78%) and specificity 71% (61% to 80%). Clinically, only history of sore throat, rash, and pyrexia contributed to the diagnosis of strep throat (p<0.05). Conclusion The high specificity of RST facilitates early diagnosis of strep throat. However, the low sensitivity of RST does not support its use as a single diagnostic tool. The sensitivity in the present study is markedly different from that reported by the manufacturer. Clinical examination is of limited value in the diagnosis of strep throat. It is important to audit the performance of new diagnostic tests, previously validated in different settings. PMID:16373800

Evaluation of the accuracy of the EasyTest™ malaria Pf/Pan Ag, a rapid diagnostic test, in Uganda.

PubMed

Chong, Chom-Kyu; Cho, Pyo Yun; Na, Byoung-Kuk; Ahn, Seong Kyu; Kim, Jin Su; Lee, Jin-Soo; Lee, Sung-Keun; Han, Eun-Taek; Kim, Hak-Yong; Park, Yun-Kyu; Cha, Seok Ho; Kim, Tong-Soo

2014-10-01

In recent years, rapid diagnostic tests (RDTs) have been widely used for malaria detection, primarily because of their simple operation, fast results, and straightforward interpretation. The Asan EasyTest™ Malaria Pf/Pan Ag is one of the most commonly used malaria RDTs in several countries, including Korea and India. In this study, we tested the diagnostic performance of this RDT in Uganda to evaluate its usefulness for field diagnosis of malaria in this country. Microscopic and PCR analyses, and the Asan EasyTest™ Malaria Pf/Pan Ag rapid diagnostic test, were performed on blood samples from 185 individuals with suspected malaria in several villages in Uganda. Compared to the microscopic analysis, the sensitivity of the RDT to detect malaria infection was 95.8% and 83.3% for Plasmodium falciparum and non-P. falciparum, respectively. Although the diagnostic sensitivity of the RDT decreased when parasitemia was ≤500 parasites/µl, it showed 96.8% sensitivity (98.4% for P. falciparum and 93.8% for non-P. falciparum) in blood samples with parasitemia ≥100 parasites/µl. The specificity of the RDT was 97.3% for P. falciparum and 97.3% for non-P. falciparum. These results collectively suggest that the accuracy of the Asan EasyTest™ Malaria Pf/Pan Ag makes it an effective point-of-care diagnostic tool for malaria in Uganda.

Evaluation of the Accuracy of the EasyTest™ Malaria Pf/Pan Ag, a Rapid Diagnostic Test, in Uganda

PubMed Central

Chong, Chom-Kyu; Cho, Pyo Yun; Na, Byoung-Kuk; Ahn, Seong Kyu; Kim, Jin Su; Lee, Jin-Soo; Lee, Sung-Keun; Han, Eun-Taek; Kim, Hak-Yong; Park, Yun-Kyu; Cha, Seok Ho

2014-01-01

In recent years, rapid diagnostic tests (RDTs) have been widely used for malaria detection, primarily because of their simple operation, fast results, and straightforward interpretation. The Asan EasyTest™ Malaria Pf/Pan Ag is one of the most commonly used malaria RDTs in several countries, including Korea and India. In this study, we tested the diagnostic performance of this RDT in Uganda to evaluate its usefulness for field diagnosis of malaria in this country. Microscopic and PCR analyses, and the Asan EasyTest™ Malaria Pf/Pan Ag rapid diagnostic test, were performed on blood samples from 185 individuals with suspected malaria in several villages in Uganda. Compared to the microscopic analysis, the sensitivity of the RDT to detect malaria infection was 95.8% and 83.3% for Plasmodium falciparum and non-P. falciparum, respectively. Although the diagnostic sensitivity of the RDT decreased when parasitemia was ≤500 parasites/µl, it showed 96.8% sensitivity (98.4% for P. falciparum and 93.8% for non-P. falciparum) in blood samples with parasitemia ≥100 parasites/µl. The specificity of the RDT was 97.3% for P. falciparum and 97.3% for non-P. falciparum. These results collectively suggest that the accuracy of the Asan EasyTest™ Malaria Pf/Pan Ag makes it an effective point-of-care diagnostic tool for malaria in Uganda. PMID:25352698

Diagnostic Performance of CT for Diagnosis of Fat-Poor Angiomyolipoma in Patients With Renal Masses: A Systematic Review and Meta-Analysis.

PubMed

Woo, Sungmin; Suh, Chong Hyun; Cho, Jeong Yeon; Kim, Sang Youn; Kim, Seung Hyup

2017-11-01

The purpose of this article is to systematically review and perform a meta-analysis of the diagnostic performance of CT for diagnosis of fat-poor angiomyolipoma (AML) in patients with renal masses. MEDLINE and EMBASE were systematically searched up to February 2, 2017. We included diagnostic accuracy studies that used CT for diagnosis of fat-poor AML in patients with renal masses, using pathologic examination as the reference standard. Two independent reviewers assessed the methodologic quality using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Sensitivity and specificity of included studies were calculated and were pooled and plotted in a hierarchic summary ROC plot. Sensitivity analyses using several clinically relevant covariates were performed to explore heterogeneity. Fifteen studies (2258 patients) were included. Pooled sensitivity and specificity were 0.67 (95% CI, 0.48-0.81) and 0.97 (95% CI, 0.89-0.99), respectively. Substantial and considerable heterogeneity was present with regard to sensitivity and specificity (I 2 = 91.21% and 78.53%, respectively). At sensitivity analyses, the specificity estimates were comparable and consistently high across all subgroups (0.93-1.00), but sensitivity estimates showed significant variation (0.14-0.82). Studies using pixel distribution analysis (n = 3) showed substantially lower sensitivity estimates (0.14; 95% CI, 0.04-0.40) compared with the remaining 12 studies (0.81; 95% CI, 0.76-0.85). CT shows moderate sensitivity and excellent specificity for diagnosis of fat-poor AML in patients with renal masses. When methods other than pixel distribution analysis are used, better sensitivity can be achieved.

Comparison of loop-mediated isothermal amplification assay and smear microscopy with culture for the diagnostic accuracy of tuberculosis.

PubMed

Gelaw, Baye; Shiferaw, Yitayal; Alemayehu, Marta; Bashaw, Abate Assefa

2017-01-17

Tuberculosis (TB) caused by Mycobacterium tuberculosis is one of the leading causes of death from infectious diseases worldwide. Sputum smear microscopy remains the most widely available pulmonary TB diagnostic tool particularly in resource limited settings. A highly sensitive diagnostic with minimal infrastructure, cost and training is required. Hence, we assessed the diagnostic performance of Loop-mediated isothermal amplification (LAMP) assay in detecting M.tuberculosis infection in sputum sample compared to LED fluorescent smear microscopy and culture. A cross-sectional study was conducted at the University of Gondar Hospital from June 01, 2015 to August 30, 2015. Pulmonary TB diagnosis using sputum LED fluorescence smear microscopy, TB-LAMP assay and culture were done. A descriptive analysis was used to determine demographic characteristics of the study participants. Analysis of sensitivity and specificity for smear microscopy and TB-LAMP compared with culture as a reference test was performed. Cohen's kappa was calculated as a measure of agreement between the tests. A total of 78 pulmonary presumptive TB patients sputum sample were analyzed. The overall sensitivity and specificity of LAMP were 75 and 98%, respectively. Among smear negative sputum samples, 33.3% sensitivity and 100% specificity of LAMP were observed. Smear microscopy showed 78.6% sensitivity and 98% specificity. LAMP and smear in series had sensitivity of 67.8% and specificity of 100%. LAMP and smear in parallel had sensitivity of 85.7% and specificity of 96%. The agreement between LAMP and fluorescent smear microscopy tests was very good (κ = 0.83, P-value ≤0.0001). TB-LAMP showed similar specificity but a slightly lower sensitivity with LED fluorescence microscopy. The specificity of LAMP and smear microscopy in series was high. The sensitivity of LAMP was insufficient for smear negative sputum samples.

Characterization of Sarcoptes scabiei Tropomyosin and Paramyosin: Immunoreactive Allergens in Scabies.

PubMed

Naz, Shumaila; Desclozeaux, Marion; Mounsey, Kate E; Chaudhry, Farhana Riaz; Walton, Shelley F

2017-09-01

Scabies is a human skin disease due to the burrowing ectoparasite Sarcoptes scabiei var. hominis resulting in intense itching and inflammation and manifesting as a skin allergy. Because of insufficient mite material and lack of in vitro propagation system for antigen preparation, scabies is a challenging disease to develop serological diagnostics. For allergen characterization, full-length S. scabiei tropomyosin (Sar s 10) was cloned, expressed in pET-15b, and assessed for reactivity with IgE antibodies from human sera. IgE binding was observed to Sar s 10 with sera collected from subjects with ordinary scabies, house dust mite (HDM)-positive and naive subjects and a diagnostic sensitivity of < 30% was observed. S. scabiei paramyosin (Sar s 11) was cloned, and expressed in pET-28a in three overlapping fragments designated Sspara1, Sspara2, and Sspara3. IgE and IgG binding was observed to Sspara2 and Sspara3 antigens with sera collected from ordinary scabies, and HDM-positive subjects, but no binding was observed with sera collected from naive subjects. Sspara2 displayed excellent diagnostic potential with 98% sensitivity and 90% specificity observed for IgE binding and 70% sensitivity for IgG. In contrast, the diagnostic sensitivity of Sspara3 was 84% for IgE binding and 40% for IgG binding. In combination, Sspara2 and Sspara3 provided an IgE sensitivity of 94%. This study shows that IgE binding to Sspara2 and Sspara3 is a highly sensitive method for diagnosis of scabies infestation in clinical practice. The developed enzyme-linked immunosorbent assay helps direct future development of a specific diagnostic tool for scabies.

The use of intrathecal analgesia and contrast radiography as preoperative diagnostic methods for digital flexor tendon sheath pathology.

PubMed

Fiske-Jackson, A R; Barker, W H J; Eliashar, E; Foy, K; Smith, R K W

2013-01-01

The sensitivity of ultrasonography for the diagnosis of manica flexoria (MF) tears within the digital flexor tendon sheath (DFTS) is lower than for diagnosis of marginal tears of the deep digital flexor tendon (DDFT). Additional diagnostic tools would assist in appropriate decision making for either conservative or surgical management. To evaluate the improvement in lameness of horses with MF or DDFT tears following intrathecal analgesia and to assess the sensitivity and specificity of contrast radiography for the diagnosis of these tears. The case records of horses presented to a referral clinic over a 7-year period that underwent intrathecal diagnostic analgesia, or intrathecal analgesia and contrast radiography, of the DFTS with subsequent tenoscopy were examined. Fifty-three limbs had intrathecal diagnostic analgesia performed and 23 contrast tenograms were assessed in horses undergoing DFTS tenoscopy. Horses with DDFT tears were significantly more likely to respond positively to intrathecal diagnostic analgesia than those with MF tears (P = 0.02). Using contrast radiography, tears of the MF were predicted with an overall sensitivity of 96% and specificity of 80%; marginal tears of the DDFT were predicted with an overall sensitivity of 57% and specificity of 84%. The results of intrathecal analgesia of the DFTS in combination with contrast radiography have a high sensitivity for predicting MF tears. The sensitivity of contrast radiography for predicting tears of the DDFT is lower but the specificity remains high. Contrast radiography performed at the same time as intrathecal analgesia provides useful information regarding the presence of MF tears and DDFT tears, which can assist in the decision of whether to manage the lameness conservatively or with tenoscopic evaluation. © 2012 EVJ Ltd.

Automated classification of focal breast lesions according to S-detect: validation and role as a clinical and teaching tool.

PubMed

Di Segni, Mattia; de Soccio, Valeria; Cantisani, Vito; Bonito, Giacomo; Rubini, Antonello; Di Segni, Gabriele; Lamorte, Sveva; Magri, Valentina; De Vito, Corrado; Migliara, Giuseppe; Bartolotta, Tommaso Vincenzo; Metere, Alessio; Giacomelli, Laura; de Felice, Carlo; D'Ambrosio, Ferdinando

2018-06-01

To assess the diagnostic performance and the potential as a teaching tool of S-detect in the assessment of focal breast lesions. 61 patients (age 21-84 years) with benign breast lesions in follow-up or candidate to pathological sampling or with suspicious lesions candidate to biopsy were enrolled. The study was based on a prospective and on a retrospective phase. In the prospective phase, after completion of baseline US by an experienced breast radiologist and S-detect assessment, 5 operators with different experience and dedication to breast radiology performed elastographic exams. In the retrospective phase, the 5 operators performed a retrospective assessment and categorized lesions with BI-RADS 2013 lexicon. Integration of S-detect to in-training operators evaluations was performed by giving priority to S-detect analysis in case of disagreement. 2 × 2 contingency tables and ROC analysis were used to assess the diagnostic performances; inter-rater agreement was measured with Cohen's k; Bonferroni's test was used to compare performances. A significance threshold of p = 0.05 was adopted. All operators showed sensitivity > 90% and varying specificity (50-75%); S-detect showed sensitivity > 90 and 70.8% specificity, with inter-rater agreement ranging from moderate to good. Lower specificities were improved by the addition of S-detect. The addition of elastography did not lead to any improvement of the diagnostic performance. S-detect is a feasible tool for the characterization of breast lesions; it has a potential as a teaching tool for the less experienced operators.

Testing the woman abuse screening tool to identify intimate partner violence in Indonesia.

PubMed

Iskandar, Livia; Braun, Kathryn L; Katz, Alan R

2015-04-01

Intimate Partner Violence (IPV) is a global public health problem. IPV prevalence in Indonesia has been estimated to be less than 1%, based on reported cases. It is likely that IPV prevalence is underreported in Indonesia, as it is in many other countries. Screening for IPV has been found to increase IPV identification, but no screening tools are in use in Indonesia. The aim of this study was to test the translated Woman Abuse Screening Tool (WAST) for detecting IPV in Indonesia. The WAST was tested against a diagnostic interview by a trained psychologist on 240 women attending two Primary Health Centers in Jakarta. IPV prevalence and the reliability, sensitivity, and specificity of the WAST were estimated. Prevalence of IPV by diagnostic interview was 36.3%, much higher than published estimates. The most common forms of IPV identified were psychological (85%) and physical abuse (24%). Internal reliability of the WAST was high (α = .801). A WAST score of 13 (out of 24) is the recommended cutoff for identifying IPV, but only 17% of the Indonesian sample scored 13 or higher. Test sensitivity of the WAST with a cutoff score of 13 was only 41.9%, with a specificity of 96.8%. With a cutoff score of 10, the sensitivity improved to 84.9%, while the specificity decreased to 61.0%. Use of the WAST with a cutoff score of 10 provides good sensitivity and reasonable specificity and would provide a much-needed screening tool for use in Indonesia. Although a lower cutoff would yield a greater proportion of false positives, most of the true cases would be identified, increasing the possibility that women experiencing abuse would receive needed assistance. © The Author(s) 2014.

Diagnostic accuracy of an identification tool for localized neuropathic pain based on the IASP criteria.

PubMed

Mayoral, Víctor; Pérez-Hernández, Concepción; Muro, Inmaculada; Leal, Ana; Villoria, Jesús; Esquivias, Ana

2018-04-27

Based on the clear neuroanatomical delineation of many neuropathic pain (NP) symptoms, a simple tool for performing a short structured clinical encounter based on the IASP diagnostic criteria was developed to identify NP. This study evaluated its accuracy and usefulness. A case-control study was performed in 19 pain clinics within Spain. A pain clinician used the experimental screening tool (the index test, IT) to assign the descriptions of non-neuropathic (nNP), non-localized neuropathic (nLNP), and localized neuropathic (LNP) to the patients' pain conditions. The reference standard was a formal clinical diagnosis provided by another pain clinician. The accuracy of the IT was compared with that of the Douleur Neuropathique en 4 questions (DN4) and the Leeds Assessment of Neuropathic Signs and Symptoms (LANSS). Six-hundred and sixty-six patients were analyzed. There was a good agreement between the IT and the reference standard (kappa =0.722). The IT was accurate in distinguishing between LNP and nLNP (83.2% sensitivity, 88.2% specificity), between LNP and the other pain categories (nLNP + nNP) (80.0% sensitivity, 90.7% specificity), and between NP and nNP (95.5% sensitivity, 89.1% specificity). The accuracy in distinguishing between NP and nNP was comparable with that of the DN4 and the LANSS. The IT took a median of 10 min to complete. A novel instrument based on an operationalization of the IASP criteria can not only discern between LNP and nLNP, but also provide a high level of diagnostic certainty about the presence of NP after a short clinical encounter.

The diagnostic test accuracy of magnetic resonance imaging, magnetic resonance arthrography and computer tomography in the detection of chondral lesions of the hip.

PubMed

Smith, Toby O; Simpson, Michael; Ejindu, Vivian; Hing, Caroline B

2013-04-01

The purpose of this study was to assess the diagnostic test accuracy of magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA) and multidetector arrays in CT arthrography (MDCT) for assessing chondral lesions in the hip joint. A review of the published and unpublished literature databases was performed to identify all studies reporting the diagnostic test accuracy (sensitivity/specificity) of MRI, MRA or MDCT for the assessment of adults with chondral (cartilage) lesions of the hip with surgical comparison (arthroscopic or open) as the reference test. All included studies were reviewed using the quality assessment of diagnostic accuracy studies appraisal tool. Pooled sensitivity, specificity, likelihood ratios and diagnostic odds ratios were calculated with 95 % confidence intervals using a random-effects meta-analysis for MRI, MRA and MDCT imaging. Eighteen studies satisfied the eligibility criteria. These included 648 hips from 637 patients. MRI indicated a pooled sensitivity of 0.59 (95 % CI: 0.49-0.70) and specificity of 0.94 (95 % CI: 0.90-0.97), and MRA sensitivity and specificity values were 0.62 (95 % CI: 0.57-0.66) and 0.86 (95 % CI: 0.83-0.89), respectively. The diagnostic test accuracy for the detection of hip joint cartilage lesions is currently superior for MRI compared with MRA. There were insufficient data to perform meta-analysis for MDCT or CTA protocols. Based on the current limited diagnostic test accuracy of the use of magnetic resonance or CT, arthroscopy remains the most accurate method of assessing chondral lesions in the hip joint.

Value of circulating cell-free DNA analysis as a diagnostic tool for breast cancer: a meta-analysis

PubMed Central

Ma, Xuelei; Zhang, Jing; Hu, Xiuying

2017-01-01

Objectives The aim of this study was to systematically evaluate the diagnostic value of cell free DNA (cfDNA) for breast cancer. Results Among 308 candidate articles, 25 with relevant diagnostic screening qualified for final analysis. The mean sensitivity, specificity and area under the curve (AUC) of SROC plots for 24 studies that distinguished breast cancer patients from healthy controls were 0.70, 0.87, and 0.9314, yielding a DOR of 32.31. When analyzed in subgroups, the 14 quantitative studies produced sensitivity, specificity, AUC, and a DOR of 0.78, 0.83, 0.9116, and 24.40. The 10 qualitative studies produced 0.50, 0.98, 0.9919, and 68.45. For 8 studies that distinguished malignant breast cancer from benign diseases, the specificity, sensitivity, AUC and DOR were 0.75, 0.79, 0.8213, and 9.49. No covariate factors had a significant correlation with relative DOR. Deek's funnel plots indicated an absence of publication bias. Materials and Methods Databases were searched for studies involving the use of cfDNA to diagnose breast cancer. The studies were analyzed to determine sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR), and the summary receiver operating characteristic (SROC). Covariates were evaluated for effect on relative DOR. Deek's Funnel plots were generated to measure publication bias. Conclusions Our analysis suggests a promising diagnostic potential of using cfDNA for breast cancer screening, but this diagnostic method is not yet independently sufficient. Further work refining qualitative cfDNA assays will improve the correct diagnosis of breast cancers. PMID:28460452

Dual-mode endomicroscopy for detection of epithelial dysplasia in the mouth: a descriptive pilot study

NASA Astrophysics Data System (ADS)

Bodenschatz, Nico; Poh, Catherine F.; Lam, Sylvia; Lane, Pierre; Guillaud, Martial; MacAulay, Calum E.

2017-08-01

Dual-mode endomicroscopy is a diagnostic tool for early cancer detection. It combines the high-resolution nuclear tissue contrast of fluorescence endomicroscopy with quantified depth-dependent epithelial backscattering as obtained by diffuse optical microscopy. In an in vivo pilot imaging study of 27 oral lesions from 21 patients, we demonstrate the complementary diagnostic value of both modalities and show correlations between grade of epithelial dysplasia and relative depth-dependent shifts in light backscattering. When combined, the two modalities provide diagnostic sensitivity to both moderate and severe epithelial dysplasia in vivo.

The Role of Computed Tomography in Blunt Abdominal Trauma.

PubMed

Karki, O B

2015-01-01

Blunt injury trauma is regularly encountered in the emergency department. Diagnostic tools that help in optimum management of blunt abdominal trauma include; Focussed Assessment Sonography for Trauma scan, Diagnostic peritoneal lavage and Computed Tomography scan. The aim of this study is to determine the validity of CT scan as an accurate diagnostic tool and its role in management of patients with blunt abdominal trauma. A prospective analysis of 80 patients of blunt abdomen trauma who were admitted in Manipal Teaching Hospital, Pokhara, Nepal within a span of 15 months was done. Demographic data, mechanism of trauma, management and outcomes were studied. Organ injuries were graded using the Organ Injury Scale guidelines. Most of the patients in our study were in the age group of 21-40 years with an M: F ratio of 2.3:1. Road traffic accident (47.5%) was the most common mechanism of injury. Spleen (27.5%) was the commonest organ injured. CT scan was superior to FAST scan and had sensitivity of 97.3% specificity 75% positive predictive value 98.6%. FAST scan had sensitivity of 78.9%, specificity 50%, positive predictive value 96% with p- value of 0.0034. 81% of patients were conservatively managed. In conjunction with close clinical monitoring, CT scan is reliable in the evaluation and management of blunt abdominal trauma patients. Our study also shows CT as a superior diagnostic modality compared to FAST scan.

Screening tests for distal symmetrical polyneuropathy in Latin American patients with type 2 diabetes mellitus.

PubMed

Gómez-Banoy, Nicolás; Cuevas, Virginia; Soler, Fernando; Pineda, Maria Fernanda; Mockus, Ismena

2017-01-01

This cross sectional study intended to evaluate two bedside tests (Neuropad and VibraTip) as screening tools for distal symmetrical polyneuropathy (DSPN) in Latin American patients with type 2 diabetes mellitus (T2D). Ninety-three Colombian patients diagnosed with T2D were recruited. Anthropometric variables, glycemic control parameters, lipid profile and renal function were assessed for each patient. DSPN was defined by a Michigan Neuropathy Screening Instrument (MNSI) clinical score greater than 2. Both Neuropad and Vibratip tests were applied to each patient. Contingency analyses were performed to evaluate the diagnostic power of both tools. The prevalence of DSPN determined clinically by MNSI was 25.8%. DSPN in these patients was associated with age, worsening renal function, and insulin treatment. The sensitivity and specificity of the Neuropad test for DSPN was 66.6% and 63% respectively. Its negative predictive value (NPV) was 84.6%. The VibraTip test exhibited a sensitivity of 54.1% and specificity of 91.3%, with a NPV of 85.1%. Neuropad and VibraTip are reliable screening tools for DSPN in Latin American population. VibraTip presents a considerable diagnostic power for DSPN in this population. Further studies regarding the cost-effectiveness of these tools in clinical practice are needed.

Diagnostic Accuracy of Natriuretic Peptides for Heart Failure in Patients with Pleural Effusion: A Systematic Review and Updated Meta-Analysis

PubMed Central

Cheng, Juan-Juan; Zhao, Shi-Di; Gao, Ming-Zhu; Huang, Hong-Yu; Gu, Bing; Ma, Ping; Chen, Yan; Wang, Jun-Hong; Yang, Cheng-Jian; Yan, Zi-He

2015-01-01

Background Previous studies have reported that natriuretic peptides in the blood and pleural fluid (PF) are effective diagnostic markers for heart failure (HF). These natriuretic peptides include N-terminal pro-brain natriuretic peptide (NT-proBNP), brain natriuretic peptide (BNP), and midregion pro-atrial natriuretic peptide (MR-proANP). This systematic review and meta-analysis evaluates the diagnostic accuracy of blood and PF natriuretic peptides for HF in patients with pleural effusion. Methods PubMed and EMBASE databases were searched to identify articles published in English that investigated the diagnostic accuracy of BNP, NT-proBNP, and MR-proANP for HF. The last search was performed on 9 October 2014. The quality of the eligible studies was assessed using the revised Quality Assessment of Diagnostic Accuracy Studies tool. The diagnostic performance characteristics (sensitivity, specificity, and other measures of accuracy) were pooled and examined using a bivariate model. Results In total, 14 studies were included in the meta-analysis, including 12 studies reporting the diagnostic accuracy of PF NT-proBNP and 4 studies evaluating blood NT-proBNP. The summary estimates of PF NT-proBNP for HF had a diagnostic sensitivity of 0.94 (95% confidence interval [CI]: 0.90–0.96), specificity of 0.91 (95% CI: 0.86–0.95), positive likelihood ratio of 10.9 (95% CI: 6.4–18.6), negative likelihood ratio of 0.07 (95% CI: 0.04–0.12), and diagnostic odds ratio of 157 (95% CI: 57–430). The overall sensitivity of blood NT-proBNP for diagnosis of HF was 0.92 (95% CI: 0.86–0.95), with a specificity of 0.88 (95% CI: 0.77–0.94), positive likelihood ratio of 7.8 (95% CI: 3.7–16.3), negative likelihood ratio of 0.10 (95% CI: 0.06–0.16), and diagnostic odds ratio of 81 (95% CI: 27–241). The diagnostic accuracy of PF MR-proANP and blood and PF BNP was not analyzed due to the small number of related studies. Conclusions BNP, NT-proBNP, and MR-proANP, either in blood or PF, are effective tools for diagnosis of HF. Additional studies are needed to rigorously evaluate the diagnostic accuracy of PF and blood MR-proANP and BNP for the diagnosis of HF. PMID:26244664

Nucleic Acid-Based Approaches for Detection of Viral Hepatitis

PubMed Central

Behzadi, Payam; Ranjbar, Reza; Alavian, Seyed Moayed

2014-01-01

Context: To determining suitable nucleic acid diagnostics for individual viral hepatitis agent, an extensive search using related keywords was done in major medical library and data were collected, categorized, and summarized in different sections. Results: Various types of molecular biology tools can be used to detect and quantify viral genomic elements and analyze the sequences. These molecular assays are proper technologies for rapidly detecting viral agents with high accuracy, high sensitivity, and high specificity. Nonetheless, the application of each diagnostic method is completely dependent on viral agent. Conclusions: Despite rapidity, automation, accuracy, cost-effectiveness, high sensitivity, and high specificity of molecular techniques, each type of molecular technology has its own advantages and disadvantages. PMID:25789132

A systematic review of the sensitivity and specificity of the toe-brachial index for detecting peripheral artery disease.

PubMed

Tehan, Peta Ellen; Santos, Derek; Chuter, Vivienne Helaine

2016-08-01

The toe-brachial index (TBI) is used as an adjunct to the ankle-brachial index (ABI) for non-invasive lower limb vascular screening. With increasing evidence suggesting limitations of the ABI for diagnosis of vascular complications, particularly in specific populations including diabetes cohorts, the TBI is being used more widely. The aim of this review was to determine the sensitivity and specificity of the TBI for detecting peripheral artery disease (PAD) in populations at risk of this disease. A database search was conducted to identify current work relating to the sensitivity and specificity of toe-brachial indices up to July 2015. Only studies using valid diagnostic imaging as a reference standard were included. The QUADAS-2 tool was used to critically appraise included articles. Seven studies met the inclusion criteria. Sensitivity of the TBI for PAD was reported in all seven studies and ranged from 45% to 100%; specificity was reported by five studies only and ranged from 16% to 100%. In conclusion, this review suggests that the TBI has variable diagnostic accuracy for the presence of PAD in specific populations at risk of developing the disease. There was a notable lack of large-scale diagnostic accuracy studies determining the diagnostic accuracy of the TBI in detecting PAD in different at-risk cohorts. However, standardised normal values need to be established for the TBI to conclusively determine the diagnostic accuracy of this test. © The Author(s) 2016.

PRNP variants in goats reduce sensitivity of detection of PrPSc by immunoassay

USDA-ARS?s Scientific Manuscript database

Immunoassays are extensively utilized in disease diagnostics with monoclonal antibodies serving as critical tools within the assay. Detection of scrapie in sheep and goats relies heavily on immunoassays including immunohistochemistry, western blotting, and ELISA. In the United States, regulatory tes...

Diagnostic Applications of Next Generation Sequencing in Immunogenetics and Molecular Oncology

PubMed Central

Grumbt, Barbara; Eck, Sebastian H.; Hinrichsen, Tanja; Hirv, Kaimo

2013-01-01

Summary With the introduction of the next generation sequencing (NGS) technologies, remarkable new diagnostic applications have been established in daily routine. Implementation of NGS is challenging in clinical diagnostics, but definite advantages and new diagnostic possibilities make the switch to the technology inevitable. In addition to the higher sequencing capacity, clonal sequencing of single molecules, multiplexing of samples, higher diagnostic sensitivity, workflow miniaturization, and cost benefits are some of the valuable features of the technology. After the recent advances, NGS emerged as a proven alternative for classical Sanger sequencing in the typing of human leukocyte antigens (HLA). By virtue of the clonal amplification of single DNA molecules ambiguous typing results can be avoided. Simultaneously, a higher sample throughput can be achieved by tagging of DNA molecules with multiplex identifiers and pooling of PCR products before sequencing. In our experience, up to 380 samples can be typed for HLA-A, -B, and -DRB1 in high-resolution during every sequencing run. In molecular oncology, NGS shows a markedly increased sensitivity in comparison to the conventional Sanger sequencing and is developing to the standard diagnostic tool in detection of somatic mutations in cancer cells with great impact on personalized treatment of patients. PMID:23922545

Diagnostic accuracy of lymphoma established by fine-needle aspiration cytological biopsy

NASA Astrophysics Data System (ADS)

Delyuzar; Amir, Z.; Suryadi, D.

2018-03-01

Based on Globocan data in 2012, it is estimated that about 14,495 Indonesians suffer from lymphoma, both Hodgkin’s lymphoma, and non-Hodgkin’s lymphoma. Some areas of specialization still doubt the accuracy of cytology diagnosis of fine needle aspiration biopsy.This study is a diagnostic test with a cross sectional analytic design to see how the cytology diagnostic accuracy of fine needle aspiration aspirate in lymphoma. It was in Department of Anatomical Pathology Faculty of Medicine USU, Haji Adam Malik Hospital, Dr.Pirngadi hospital, or private clinic in Medan. Peripheral cytology technique biopsy of fine needle aspiration on lymph node subsequently stained with Giemsa, when the cytology of lymphoma is obtained and confirmed by histopathologic examination. Cytology and histopathologic examination will be tested by Diagnostic Test and assessed for its sensitivity and specificity. The diagnostic of lymphoma cytology provides 93.33% sensitivity and 92.31% specificity when confirmed by histopathological examination. Positive predictive value and negative predictive value of 96.55% and 85.71% respectively. In conclusion, the cytology of fine needle aspiration biopsy is accurate enough to be used as a diagnostic tool, so it is advisable to establish a lymphoma diagnosis to perform a needle aspiration biopsy examination.

Latest generation of flat detector CT as a peri-interventional diagnostic tool: a comparative study with multidetector CT.

PubMed

Leyhe, Johanna Rosemarie; Tsogkas, Ioannis; Hesse, Amélie Carolina; Behme, Daniel; Schregel, Katharina; Papageorgiou, Ismini; Liman, Jan; Knauth, Michael; Psychogios, Marios-Nikos

2017-12-01

Flat detector CT (FDCT) has been used as a peri-interventional diagnostic tool in numerous studies with mixed results regarding image quality and detection of intracranial lesions. We compared the diagnostic aspects of the latest generation FDCT with standard multidetector CT (MDCT). 102 patients were included in our retrospective study. All patients had undergone interventional procedures. FDCT was acquired peri-interventionally and compared with postinterventional MDCT regarding depiction of ventricular/subarachnoidal spaces, detection of intracranial hemorrhage, and delineation of ischemic lesions using an ordinal scale. Ischemic lesions were quantified with the Alberta Stroke Program Early CT Scale (ASPECTS) on both examinations. Two neuroradiologists with varying grades of experience and a medical student scored the anonymized images separately, blinded to the clinical history. The two methods were of equal diagnostic value regarding evaluation of the ventricular system and the subarachnoidal spaces. Subarachnoidal, intraventricular, and parenchymal hemorrhages were detected with a sensitivity of 95%, 97%, and 100% and specificity of 97%, 100%, and 99%, respectively, using FDCT. Gray-white differentiation was feasible in the majority of FDCT scans, and ischemic lesions were detected with a sensitivity of 71% on FDCT, compared with MDCT scans. The mean difference in ASPECTS values on FDCT and MDCT was 0.5 points (95% CI 0.12 to 0.88). The latest generation of FDCT is a reliable and accurate tool for the detection of intracranial hemorrhage. Gray-white differentiation is feasible in the supratentorial region. 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/.

Methodological quality of diagnostic accuracy studies on non-invasive coronary CT angiography: influence of QUADAS (Quality Assessment of Diagnostic Accuracy Studies included in systematic reviews) items on sensitivity and specificity.

PubMed

Schueler, Sabine; Walther, Stefan; Schuetz, Georg M; Schlattmann, Peter; Dewey, Marc

2013-06-01

To evaluate the methodological quality of diagnostic accuracy studies on coronary computed tomography (CT) angiography using the QUADAS (Quality Assessment of Diagnostic Accuracy Studies included in systematic reviews) tool. Each QUADAS item was individually defined to adapt it to the special requirements of studies on coronary CT angiography. Two independent investigators analysed 118 studies using 12 QUADAS items. Meta-regression and pooled analyses were performed to identify possible effects of methodological quality items on estimates of diagnostic accuracy. The overall methodological quality of coronary CT studies was merely moderate. They fulfilled a median of 7.5 out of 12 items. Only 9 of the 118 studies fulfilled more than 75 % of possible QUADAS items. One QUADAS item ("Uninterpretable Results") showed a significant influence (P = 0.02) on estimates of diagnostic accuracy with "no fulfilment" increasing specificity from 86 to 90 %. Furthermore, pooled analysis revealed that each QUADAS item that is not fulfilled has the potential to change estimates of diagnostic accuracy. The methodological quality of studies investigating the diagnostic accuracy of non-invasive coronary CT is only moderate and was found to affect the sensitivity and specificity. An improvement is highly desirable because good methodology is crucial for adequately assessing imaging technologies. • Good methodological quality is a basic requirement in diagnostic accuracy studies. • Most coronary CT angiography studies have only been of moderate design quality. • Weak methodological quality will affect the sensitivity and specificity. • No improvement in methodological quality was observed over time. • Authors should consider the QUADAS checklist when undertaking accuracy studies.

Diagnostic accuracy of contrast-enhanced ultrasound in assessing the therapeutic response to radio frequency ablation for liver tumors: systematic review and meta-analysis.

PubMed

Xuan, Min; Zhou, Fengsheng; Ding, Yan; Zhu, Qiaoying; Dong, Ji; Zhou, Hao; Cheng, Jun; Jiang, Xiao; Wu, Pengxi

2018-04-01

To review the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) used to detect residual or recurrent liver tumors after radiofrequency ablation (RFA). This technique uses contrast-enhanced computer tomography or/and contrast-enhanced magnetic resonance imaging as the gold standard of investigation. MEDLINE, EMBASE, and COCHRANE were systematically searched for all potentially eligible studies comparing CEUS with the reference standard that follows RFA. Risk of bias and applicability concerns were addressed by adopting the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Pooled point estimates for sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratios (DOR) with 95% CI were computed before plotting the sROC (summary receiver operating characteristic) curve. Meta-regression and subgroup analysis were used to identify the source of the heterogeneity that was detected. Publication bias was evaluated using Deeks' funnel plot asymmetry test. Ten eligible studies on 1162 lesions that occurred between 2001 and 2016 were included in the final analysis. The quality of the included studies assessed by the QUADAS-2 tool was considered reasonable. The pooled sensitivity and specificity of CEUS in detecting residual or recurrent liver tumors had the following values: 0.90 (95% CI 0.85-0.94) and 1.00 (95% CI 0.99-1.00), respectively. Overall DOR was 420.10 (95% CI 142.30-1240.20). The sources of heterogeneity could not be precisely identified by meta-regression or subgroup analysis. No evidence of publication bias was found. This study confirmed that CEUS exhibits high sensitivity and specificity in assessing therapeutic responses to RFA for liver tumors.

[Effects of critical ultrasonic management of Peking Union Medical College Hospital on the etiological diagnosis of patients with acute respiratory failure].

PubMed

Zhao, Hua; Wang, Xiaoting; Liu, Dawei; Zhang, Hongmin; He, Huaiwu; Long, Yun

2015-12-15

To evaluate the diagnostic value and potential therapeutic impact of Peking Union Medical College Hospital critical ultrasonic management (PCUM) in the early management of critically ill patients with acute respiratory failure (ARF). Patients admitted into the ICU of Peking Union Medical College Hospital for ARF were consecutively recruited over a 18-month period. Patients were randomly divided into conventional group and PCUM group (critical care ultrasonic examination was added in addition to conventional examinations). The two groups were compared with respect to time to preliminary diagnosis, time to final diagnosis, diagnostic accuracy, time to treatment response, time to other examination. A total of 187 patients were included in this study. The two groups showed no significant differences in general clinical information or final diagnosis (P > 0.05). The PCUM group had a shorter time to preliminary diagnosis, time to final diagnosis, time to treatment response, time to X-ray/CT examination, and a higher diagnostic accuracy than the conventional group (P < 0.001). PCUM had high sensitivity and specificity for the diagnosis of acute respiratory distress syndrome (ARDS) (sensitivity 92.0%, specificity 98.5%), acute pulmonary edema (sensitivity 94.7%, specificity 96.1%), pulmonary consolidation (sensitivity 85.7%, specificity 98.6%), COPD/asthma (sensitivity 84.2%, specificity 98.7%). The PCUM is seem to be an attractive complementary diagnostic tool and able to contribute to an early therapeutic decision for the patients with ARF.

Diagnostic indices for vertiginous diseases

PubMed Central

2010-01-01

Background Vertigo and dizziness are symptoms which are reported frequently in clinical practice. We aimed to develop diagnostic indices for four prevalent vertiginous diseases: benign paroxysmal positional vertigo (BPPV), Menière's disease (MD), vestibular migraine (VM), and phobic postural vertigo (PPV). Methods Based on a detailed questionnaire handed out to consecutive patients presenting for the first time in our dizziness clinic we preselected a set of seven questions with desirable diagnostic properties when compared with the final diagnosis after medical workup. Using exact logistic regression analysis diagnostic scores, each comprising of four to six items that can simply be added up, were built for each of the four diagnoses. Results Of 193 patients 131 questionnaires were left after excluding those with missing consent or data. Applying the suggested cut-off points, sensitivity and specificity were 87.5 and 93.5% for BPPV, 100 and 87.4% for MD, 92.3 and 83.7% for VM, 73.7 and 84.1% for PPV, respectively. By changing the cut-off points sensitivity and specificity can be adjusted to meet diagnostic needs. Conclusions The diagnostic indices showed promising diagnostic properties. Once further validated, they could provide an ease to use and yet flexible tool for screening vertigo in clinical practice and epidemiological research. PMID:20973968

Two non-invasive diagnostic tools for invasive aspergilosis: (1-3)-beta-D-glucan and the galactomannan assay.

PubMed

Kelaher, Amy

2006-01-01

Invasive aspergillosis (IA) is a serious cause of morbidity and mortality among immunocompromised patients. Prompt and non-invasive methods for diagnosing IA are needed to improve the management of this life-threatening infection in patients with hematological disorders. In summary, this retrospective review of studies performed on the two assays finds that both assays have high sensitivity and specificity but are more useful when used together as a diagnostic strategy for patients with invasive aspergillosis.

[Dogs as a diagnostic tool--utopian dream or unexploited possibility?].

PubMed

Klockars, Tuomas

2016-01-01

The dog's sense of smell has been estimated to be as much as 100 000 times more sensitive than that of man. While the dog's sense of smell is utilized by various authorities, medical exploitation of dogs is scarce. A disorder causes in the body metabolic changes, which could possibly be detected by using trained dogs. Promising studies have been published in recent years about the use of diagnostic dogs in identifying cancers or antibiotic-associated diarrhea, for example.

Portable Biomarker Detection with Magnetic Nanotags

PubMed Central

Hall, Drew A.; Wang, Shan X.; Murmann, Boris; Gaster, Richard S.

2012-01-01

This paper presents a hand-held, portable biosensor platform for quantitative biomarker measurement. By combining magnetic nanoparticle (MNP) tags with giant magnetoresistive (GMR) spin-valve sensors, the hand-held platform achieves highly sensitive (picomolar) and specific biomarker detection in less than 20 minutes. The rapid analysis and potential low cost make this technology ideal for point-of-care (POC) diagnostics. Furthermore, this platform is able to detect multiple biomarkers simultaneously in a single assay, creating a promising diagnostic tool for a vast number of applications. PMID:22495252

Evaluating the diagnostic accuracy of the Xpert MTB/RIF assay on bronchoalveolar lavage fluid: A retrospective study.

PubMed

Lu, Yanjun; Zhu, Yaowu; Shen, Na; Tian, Lei; Sun, Ziyong

2018-02-08

Limited data on the diagnostic accuracy of the Xpert MTB/RIF assay using bronchoalveolar lavage fluid from patients with suspected pulmonary tuberculosis (PTB) have been reported in China. Therefore, a retrospective study was designed to evaluate the diagnostic accuracy of this assay. Clinical, radiological, and microbiological characteristics of 238 patients with suspected PTB were reviewed retrospectively. The sensitivity, specificity, positive predictive value, and negative predictive value for the diagnosis of active PTB were calculated for the Xpert MTB/RIF assay using TB culture or final diagnosis based on clinical and radiological evaluation as the reference standard. The sensitivity and specificity of the Xpert MTB/RIF assay were 84.5% and 98.9%, respectively, and those for smear microscopy were 36.2% and 100%, respectively, when compared to the culture method. However, compared with the sensitivity and specificity of final diagnosis based on clinical and radiological evaluation, the sensitivity and specificity of the assay were 72.9% and 98.7%, respectively, which were significantly higher than those for smear microscopy. The Xpert MTB/RIF assay on bronchoalveolar lavage fluid could serve as an additional rapid diagnostic tool for PTB in a high TB-burden country and improve the time to TB treatment initiation in patients with PTB. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

The Generalized Anxiety Disorder Screener (GAD-7) and the anxiety module of the Hospital and Depression Scale (HADS-A) as screening tools for generalized anxiety disorder among cancer patients.

PubMed

Esser, Peter; Hartung, Tim J; Friedrich, Michael; Johansen, Christoffer; Wittchen, Hans-Ulrich; Faller, Hermann; Koch, Uwe; Härter, Martin; Keller, Monika; Schulz, Holger; Wegscheider, Karl; Weis, Joachim; Mehnert, Anja

2018-06-01

Anxiety in cancer patients may represent a normal psychological reaction. To detect patients with pathological levels, appropriate screeners with established cut-offs are needed. Given that previous research is sparse, we investigated the diagnostic accuracy of 2 frequently used screening tools in detecting generalized anxiety disorder (GAD). We used data of a multicenter study including 2141 cancer patients. Diagnostic accuracy was investigated for the Generalized Anxiety Disorder Screener (GAD-7) and the anxiety module of the Hospital Anxiety and Depression Scale (HADS-A). GAD, assessed with the Composite International Diagnostic Interview for Oncology, served as a reference standard. Overall accuracy was measured with the area under the receiver operating characteristics curve (AUC). The AUC of the 2 screeners were statistically compared. We also calculated accuracy measures for selected cut-offs. Diagnostic accuracy could be interpreted as adequate for both screeners, with an identical AUC of .81 (95% CI: .79-.82). Consequently, the 2 screeners did not differ in their performance (P = .86). The best balance between sensitivity and specificity was found for cut-offs ≥7 (GAD-7) and ≥8 (HADS-A). The officially recommended thresholds for the GAD-7 (≥ 10) and the HADS-A (≥11) showed low sensitivities of 55% and 48%, respectively. The GAD-7 and HADS-A showed AUC of adequate diagnostic accuracy and hence are applicable for GAD screening in cancer patients. Nevertheless, the choice of optimal cut-offs should be carefully evaluated. Copyright © 2018 John Wiley & Sons, Ltd.

Simulation of light transport in arthritic- and non-arthritic human fingers

NASA Astrophysics Data System (ADS)

Milanic, Matija; Paluchowski, Lukasz A.; Randeberg, Lise L.

2014-03-01

Rheumatoid arthritis is a disease that frequently leads to joint destruction. It has high incidence rates worldwide, and the disease significantly reduces patient's quality of life due to pain, swelling and stiffness of the affected joints. Early diagnosis is necessary to improve course of the disease, therefore sensitive and accurate diagnostic tools are required. Optical imaging techniques have capability for early diagnosis and monitoring of arthritis. As compared to conventional diagnostic techniques optical technique is a noninvasive, noncontact and fast way of collecting diagnostic information. However, a realistic model of light transport in human joints is needed for understanding and developing of such optical diagnostic tools. The aim of this study is to develop a 3D numerical model of light transport in a human finger. The model will guide development of a hyperspectral imaging (HSI) diagnostic modality for arthritis in human fingers. The implemented human finger geometry is based on anatomical data. Optical data of finger tissues are adjusted to represent either an arthritic or an unaffected finger. The geometry and optical data serve as input into a 3D Monte Carlo method, which calculate diffuse reflectance, transmittance and absorbed energy distributions. The parameters of the model are optimized based on HIS-measurements of human fingers. The presented model serves as an important tool for understanding and development of HSI as an arthritis diagnostic modality. Yet, it can be applied to other optical techniques and finger diseases.

Diagnostic accuracy of repetition tasks for the identification of specific language impairment (SLI) in bilingual children: evidence from Russian and Hebrew.

PubMed

Armon-Lotem, Sharon; Meir, Natalia

2016-11-01

Previous research demonstrates that repetition tasks are valuable tools for diagnosing specific language impairment (SLI) in monolingual children in English and a variety of other languages, with non-word repetition (NWR) and sentence repetition (SRep) yielding high levels of sensitivity and specificity. Yet, only a few studies have addressed the diagnostic accuracy of repetition tasks in bilingual children, and most available research focuses on English-Spanish sequential bilinguals. To evaluate the efficacy of three repetition tasks (forward digit span (FWD), NWR and SRep) in order to distinguish mono- and bilingual children with and without SLI in Russian and Hebrew. A total of 230 mono- and bilingual children aged 5;5-6;8 participated in the study: 144 bilingual Russian-Hebrew-speaking children (27 with SLI); and 52 monolingual Hebrew-speaking children (14 with SLI) and 34 monolingual Russian-speaking children (14 with SLI). Parallel repetition tasks were designed in both Russian and Hebrew. Bilingual children were tested in both languages. The findings confirmed that NWR and SRep are valuable tools in distinguishing monolingual children with and without SLI in Russian and Hebrew, while the results for FWD were mixed. Yet, testing of bilingual children with the same tools using monolingual cut-off points resulted in inadequate diagnostic accuracy. We demonstrate, however, that the use of bilingual cut-off points yielded acceptable levels of diagnostic accuracy. The combination of SRep tasks in L1/Russian and L2/Hebrew yielded the highest overall accuracy (i.e., 94%), but even SRep alone in L2/Hebrew showed excellent levels of sensitivity (i.e., 100%) and specificity (i.e., 89%), reaching 91% of total diagnostic accuracy. The results are very promising for identifying SLI in bilingual children and for showing that testing in the majority language with bilingual cut-off points can provide an accurate classification. © 2016 Royal College of Speech and Language Therapists.

Case finding of lifestyle and mental health disorders in primary care: validation of the ‘CHAT’ tool

PubMed Central

Goodyear-Smith, Felicity; Coupe, Nicole M; Arroll, Bruce; Elley, C Raina; Sullivan, Sean; McGill, Anne-Thea

2008-01-01

Background Primary care is accessible and ideally placed for case finding of patients with lifestyle and mental health risk factors and subsequent intervention. The short self-administered Case-finding and Help Assessment Tool (CHAT) was developed for lifestyle and mental health assessment of adult patients in primary health care. This tool checks for tobacco use, alcohol and other drug misuse, problem gambling, depression, anxiety and stress, abuse, anger problems, inactivity, and eating disorders. It is well accepted by patients, GPs and nurses. Aim To assess criterion-based validity of CHAT against a composite gold standard. Design of study Conducted according to the Standards for Reporting of Diagnostic Accuracy statement for diagnostic tests. Setting Primary care practices in Auckland, New Zealand. Method One thousand consecutive adult patients completed CHAT and a composite gold standard. Sensitivities, specificities, positive and negative predictive values, and likelihood ratios were calculated. Results Response rates for each item ranged from 79.6 to 99.8%. CHAT was sensitive and specific for almost all issues screened, except exercise and eating disorders. Sensitivity ranged from 96% (95% confidence interval [CI] = 87 to 99%) for major depression to 26% (95% CI = 22 to 30%) for exercise. Specificity ranged from 97% (95% CI = 96 to 98%) for problem gambling and problem drug use to 40% (95% CI = 36 to 45%) for exercise. All had high likelihood ratios (3–30), except exercise and eating disorders. Conclusion CHAT is a valid and acceptable case-finding tool for most common lifestyle and mental health conditions. PMID:18186993

Confocal microscopy patterns in nonmelanoma skin cancer and clinical applications.

PubMed

González, S; Sánchez, V; González-Rodríguez, A; Parrado, C; Ullrich, M

2014-06-01

Reflectance confocal microscopy is currently the most promising noninvasive diagnostic tool for studying cutaneous structures between the stratum corneum and the superficial reticular dermis. This tool gives real-time images parallel to the skin surface; the microscopic resolution is similar to that of conventional histology. Numerous studies have identified the main confocal features of various inflammatory skin diseases and tumors, demonstrating the good correlation of these features with certain dermatoscopic patterns and histologic findings. Confocal patterns and diagnostic algorithms have been shown to have high sensitivity and specificity in melanoma and nonmelanoma skin cancer. Possible present and future applications of this noninvasive technology are wide ranging and reach beyond its use in noninvasive diagnosis. This tool can also be used, for example, to evaluate dynamic skin processes that occur after UV exposure or to assess tumor response to noninvasive treatments such as photodynamic therapy. We explain the characteristic confocal features found in the main nonmelanoma skin tumors and discuss possible applications for this novel diagnostic technique in routine dermatology practice. Copyright © 2012 Elsevier España, S.L. and AEDV. All rights reserved.

Development and evaluation of a Loop Mediated Isothermal Amplification (LAMP) technique for the detection of hookworm (Necator americanus) infection in fecal samples.

PubMed

Mugambi, Robert Muriuki; Agola, Eric L; Mwangi, Ibrahim N; Kinyua, Johnson; Shiraho, Esther Andia; Mkoji, Gerald M

2015-11-06

Hookworm infection is a major concern in sub-Saharan Africa, particularly in children and pregnant women. Necator americanus and Ancylostoma duodenale are responsible for this condition. Hookworm disease is one of the Neglected tropical diseases (NTDs) that are targeted for elimination through global mass chemotherapy. To support this there is a need for reliable diagnostic tools. The conventional diagnostic test, Kato-Katz that is based on microscopic detection of parasite ova in faecal samples, is not effective due to its low sensitivity that is brought about mainly by non-random distribution of eggs in stool and day to day variation in egg output. It is tedious, cumbersome to perform and requires experience for correct diagnosis. LAMP-based tests are simple, relatively cheap, offer greater sensitivity, specificity than existing tests, have high throughput capability, and are ideal for use at the point of care. We have developed a LAMP diagnostic test for detection of hookworm infection in faecal samples. LAMP relies on auto cycling strand displacement DNA synthesis performed at isothermal temperature by Bst polymerase and a set of 4 specific primers. The primers used in the LAMP assay were based on the second Internal Transcribed Spacer (ITS-2) region and designed using Primer Explorer version 4 Software. The ITS-2 region of the ribosomal gene (rDNA) was identified as a suitable target due to its low mutation rates and substantial differences between species. DNA was extracted directly from human faecal samples, followed by LAMP amplification at isothermal temperature of 63 °C for 1 h. Amplicons were visualized using gel electrophoresis and SYBR green dye. Both specificity and sensitivity of the assay were determined. The LAMP based technique developed was able to detect N. americanus DNA in faecal samples. The assay showed 100 % specificity and no cross-reaction was observed with other helminth parasites (S. mansoni, A. lumbricoides or T. trichiura). The developed LAMP assay was 97 % sensitive and DNA at concentrations as low as 0.4 fg were amplified. The LAMP assay developed is an appropriate diagnostic method for the detection of N. americanus DNA in human stool samples because of its simplicity, low cost, sensitivity, and specificity. It holds great promise as a useful diagnostic tool for use in disease control where infection intensities have been significantly reduced.

A comparison of bivariate, multivariate random-effects, and Poisson correlated gamma-frailty models to meta-analyze individual patient data of ordinal scale diagnostic tests.

PubMed

Simoneau, Gabrielle; Levis, Brooke; Cuijpers, Pim; Ioannidis, John P A; Patten, Scott B; Shrier, Ian; Bombardier, Charles H; de Lima Osório, Flavia; Fann, Jesse R; Gjerdingen, Dwenda; Lamers, Femke; Lotrakul, Manote; Löwe, Bernd; Shaaban, Juwita; Stafford, Lesley; van Weert, Henk C P M; Whooley, Mary A; Wittkampf, Karin A; Yeung, Albert S; Thombs, Brett D; Benedetti, Andrea

2017-11-01

Individual patient data (IPD) meta-analyses are increasingly common in the literature. In the context of estimating the diagnostic accuracy of ordinal or semi-continuous scale tests, sensitivity and specificity are often reported for a given threshold or a small set of thresholds, and a meta-analysis is conducted via a bivariate approach to account for their correlation. When IPD are available, sensitivity and specificity can be pooled for every possible threshold. Our objective was to compare the bivariate approach, which can be applied separately at every threshold, to two multivariate methods: the ordinal multivariate random-effects model and the Poisson correlated gamma-frailty model. Our comparison was empirical, using IPD from 13 studies that evaluated the diagnostic accuracy of the 9-item Patient Health Questionnaire depression screening tool, and included simulations. The empirical comparison showed that the implementation of the two multivariate methods is more laborious in terms of computational time and sensitivity to user-supplied values compared to the bivariate approach. Simulations showed that ignoring the within-study correlation of sensitivity and specificity across thresholds did not worsen inferences with the bivariate approach compared to the Poisson model. The ordinal approach was not suitable for simulations because the model was highly sensitive to user-supplied starting values. We tentatively recommend the bivariate approach rather than more complex multivariate methods for IPD diagnostic accuracy meta-analyses of ordinal scale tests, although the limited type of diagnostic data considered in the simulation study restricts the generalization of our findings. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diagnostic performance of rapid diagnostic tests for the diagnosis of malaria at public health facilities in north-west Ethiopia.

PubMed

Getnet, Gebeyaw; Getie, Sisay; Srivastava, Mitaly; Birhan, Wubet; Fola, Abebe A; Noedl, Harald

2015-11-01

To assess the performance of RDTs against nested polymerase chain reaction (nPCR) for the diagnosis of malaria in public health facilities in north-western Ethiopia. Cross-sectional study at public health facilities in North Gondar, Ethiopia, of 359 febrile patients with signs and symptoms consistent with malaria. Finger prick blood samples were collected for testing in a P. falciparum/pan-malaria RDTs and for molecular analysis. Sensitivity, specificity and predictive values were determined for the RDTs using nPCR as reference diagnostic method. Kappa value was determined to demonstrate the consistency of the results between the diagnostic tools. By RDTs, 22.28% (80/359) of patients tested positive for malaria, and by nPCR, 27.02% (97/359) did. In nPCR, 1.67% (6/359) and 0.28% (1/359) samples were positive for P. ovale and P. malariae, which had almost all tested negative in the RDTs. The sensitivity, specificity, positive and negative predictive values of RDTs for the diagnosis of malaria were 62.9%, 92.7%, 76.3% and 87.1%, respectively, with 0.589 measurement agreement between RDTs and nPCR. The sensitivity and specificity of RDTs for P. falciparum identification only were 70.8% and 95.2%, and 65.2% and 93.1% for P. vivax. Although RDTs are commonly used at health posts in resource-limited environments, their sensitivity and specificity for the detection and species identification of Plasmodium parasites were poor compared to nPCR, suggesting caution in interpreting RDTs results. Particularly, in the light of expanded efforts to eliminate malaria in the country, more sensitive diagnostic procedures will be needed. © 2015 John Wiley & Sons Ltd.

Current and future molecular diagnostics for ocular infectious diseases.

PubMed

Doan, Thuy; Pinsky, Benjamin A

2016-11-01

Confirmation of ocular infections can pose great challenges to the clinician. A fundamental limitation is the small amounts of specimen that can be obtained from the eye. Molecular diagnostics can circumvent this limitation and have been shown to be more sensitive than conventional culture. The purpose of this review is to describe new molecular methods and to discuss the applications of next-generation sequencing-based approaches in the diagnosis of ocular infections. Efforts have focused on improving the sensitivity of pathogen detection using molecular methods. This review describes a new molecular target for Toxoplasma gondii-directed polymerase chain reaction assays. Molecular diagnostics for Chlamydia trachomatis and Acanthamoeba species are also discussed. Finally, we describe a hypothesis-free approach, metagenomic deep sequencing, which can detect DNA and RNA pathogens from a single specimen in one test. In some cases, this method can provide the geographic location and timing of the infection. Pathogen-directed PCRs have been powerful tools in the diagnosis of ocular infections for over 20 years. The use of next-generation sequencing-based approaches, when available, will further improve sensitivity of detection with the potential to improve patient care.

Diagnostic accuracy of serological diagnosis of hepatitis C and B using dried blood spot samples (DBS): two systematic reviews and meta-analyses.

PubMed

Lange, Berit; Cohn, Jennifer; Roberts, Teri; Camp, Johannes; Chauffour, Jeanne; Gummadi, Nina; Ishizaki, Azumi; Nagarathnam, Anupriya; Tuaillon, Edouard; van de Perre, Philippe; Pichler, Christine; Easterbrook, Philippa; Denkinger, Claudia M

2017-11-01

Dried blood spots (DBS) are a convenient tool to enable diagnostic testing for viral diseases due to transport, handling and logistical advantages over conventional venous blood sampling. A better understanding of the performance of serological testing for hepatitis C (HCV) and hepatitis B virus (HBV) from DBS is important to enable more widespread use of this sampling approach in resource limited settings, and to inform the 2017 World Health Organization (WHO) guidance on testing for HBV/HCV. We conducted two systematic reviews and meta-analyses on the diagnostic accuracy of HCV antibody (HCV-Ab) and HBV surface antigen (HBsAg) from DBS samples compared to venous blood samples. MEDLINE, EMBASE, Global Health and Cochrane library were searched for studies that assessed diagnostic accuracy with DBS and agreement between DBS and venous sampling. Heterogeneity of results was assessed and where possible a pooled analysis of sensitivity and specificity was performed using a bivariate analysis with maximum likelihood estimate and 95% confidence intervals (95%CI). We conducted a narrative review on the impact of varying storage conditions or limits of detection in subsets of samples. The QUADAS-2 tool was used to assess risk of bias. For the diagnostic accuracy of HBsAg from DBS compared to venous blood, 19 studies were included in a quantitative meta-analysis, and 23 in a narrative review. Pooled sensitivity and specificity were 98% (95%CI:95%-99%) and 100% (95%CI:99-100%), respectively. For the diagnostic accuracy of HCV-Ab from DBS, 19 studies were included in a pooled quantitative meta-analysis, and 23 studies were included in a narrative review. Pooled estimates of sensitivity and specificity were 98% (CI95%:95-99) and 99% (CI95%:98-100), respectively. Overall quality of studies and heterogeneity were rated as moderate in both systematic reviews. HCV-Ab and HBsAg testing using DBS compared to venous blood sampling was associated with excellent diagnostic accuracy. However, generalizability is limited as no uniform protocol was applied and most studies did not use fresh samples. Future studies on diagnostic accuracy should include an assessment of impact of environmental conditions common in low resource field settings. Manufacturers also need to formally validate their assays for DBS for use with their commercial assays.

Assessment of OmpATb as a Novel Antigen for the Diagnosis of Bovine Tuberculosis

USDA-ARS?s Scientific Manuscript database

In search for better tools to control bovine tuberculosis, the development of diagnostic tests with improved specificity and sensitivity has a high priority. We chose to search for novel immunodiagnostic reagents. In this study, Rv0899 (Outer membrane protein A of Mycobacterium tuberculosis, OmpATb)...

Laser machined plastic laminates. Towards portable diagnostic devices for use in low resource environments

DOE PAGES

Harper, Jason C.; Carson, Bryan D.; Bachand, George D.; ...

2015-07-14

Despite significant progress in development of bioanalytical devices cost, complexity, access to reagents and lack of infrastructure have prevented use of these technologies in resource-limited regions. To provide a sustainable tool in the global effort to combat infectious diseases the diagnostic device must be low cost, simple to operate and read, robust, and have sensitivity and specificity comparable to laboratory analysis. Thus, in this mini-review we describe recent work using laser machined plastic laminates to produce diagnostic devices that are capable of a wide variety of bioanalytical measurements and show great promise towards future use in low-resource environments.

Smartphone-Based Fluorescent Diagnostic System for Highly Pathogenic H5N1 Viruses.

PubMed

Yeo, Seon-Ju; Choi, Kyunghan; Cuc, Bui Thi; Hong, Nguyen Ngoc; Bao, Duong Tuan; Ngoc, Nguyen Minh; Le, Mai Quynh; Hang, Nguyen Le Khanh; Thach, Nguyen Co; Mallik, Shyam Kumar; Kim, Hak Sung; Chong, Chom-Kyu; Choi, Hak Soo; Sung, Haan Woo; Yu, Kyoungsik; Park, Hyun

2016-01-01

Field diagnostic tools for avian influenza (AI) are indispensable for the prevention and controlled management of highly pathogenic AI-related diseases. More accurate, faster and networked on-site monitoring is demanded to detect such AI viruses with high sensitivity as well as to maintain up-to-date information about their geographical transmission. In this work, we assessed the clinical and field-level performance of a smartphone-based fluorescent diagnostic device with an efficient reflective light collection module using a coumarin-derived dendrimer-based fluorescent lateral flow immunoassay. By application of an optimized bioconjugate, a smartphone-based diagnostic device had a two-fold higher detectability as compared to that of the table-top fluorescence strip reader for three different AI subtypes (H5N3, H7N1, and H9N2). Additionally, in a clinical study of H5N1-confirmed patients, the smartphone-based diagnostic device showed a sensitivity of 96.55% (28/29) [95% confidence interval (CI): 82.24 to 99.91] and a specificity of 98.55% (68/69) (95% CI: 92.19 to 99.96). The measurement results from the distributed individual smartphones were wirelessly transmitted via short messaging service and collected by a centralized database system for further information processing and data mining. Smartphone-based diagnosis provided highly sensitive measurement results for H5N1 detection within 15 minutes. Because of its high sensitivity, portability and automatic reporting feature, the proposed device will enable agile identification of patients and efficient control of AI dissemination.

Smartphone-Based Fluorescent Diagnostic System for Highly Pathogenic H5N1 Viruses

PubMed Central

Yeo, Seon-Ju; Choi, Kyunghan; Cuc, Bui Thi; Hong, Nguyen Ngoc; Bao, Duong Tuan; Ngoc, Nguyen Minh; Le, Mai Quynh; Hang, Nguyen Le Khanh; Thach, Nguyen Co; Mallik, Shyam Kumar; Kim, Hak Sung; Chong, Chom-Kyu; Choi, Hak Soo; Sung, Haan Woo; Yu, Kyoungsik; Park, Hyun

2016-01-01

Field diagnostic tools for avian influenza (AI) are indispensable for the prevention and controlled management of highly pathogenic AI-related diseases. More accurate, faster and networked on-site monitoring is demanded to detect such AI viruses with high sensitivity as well as to maintain up-to-date information about their geographical transmission. In this work, we assessed the clinical and field-level performance of a smartphone-based fluorescent diagnostic device with an efficient reflective light collection module using a coumarin-derived dendrimer-based fluorescent lateral flow immunoassay. By application of an optimized bioconjugate, a smartphone-based diagnostic device had a two-fold higher detectability as compared to that of the table-top fluorescence strip reader for three different AI subtypes (H5N3, H7N1, and H9N2). Additionally, in a clinical study of H5N1-confirmed patients, the smartphone-based diagnostic device showed a sensitivity of 96.55% (28/29) [95% confidence interval (CI): 82.24 to 99.91] and a specificity of 98.55% (68/69) (95% CI: 92.19 to 99.96). The measurement results from the distributed individual smartphones were wirelessly transmitted via short messaging service and collected by a centralized database system for further information processing and data mining. Smartphone-based diagnosis provided highly sensitive measurement results for H5N1 detection within 15 minutes. Because of its high sensitivity, portability and automatic reporting feature, the proposed device will enable agile identification of patients and efficient control of AI dissemination. PMID:26877781

Use of machine learning to improve autism screening and diagnostic instruments: effectiveness, efficiency, and multi-instrument fusion

PubMed Central

Bone, Daniel; Bishop, Somer; Black, Matthew P.; Goodwin, Matthew S.; Lord, Catherine; Narayanan, Shrikanth S.

2016-01-01

Background Machine learning (ML) provides novel opportunities for human behavior research and clinical translation, yet its application can have noted pitfalls (Bone et al., 2015). In this work, we fastidiously utilize ML to derive autism spectrum disorder (ASD) instrument algorithms in an attempt to improve upon widely-used ASD screening and diagnostic tools. Methods The data consisted of Autism Diagnostic Interview-Revised (ADI-R) and Social Responsiveness Scale (SRS) scores for 1,264 verbal individuals with ASD and 462 verbal individuals with non-ASD developmental or psychiatric disorders (DD), split at age 10. Algorithms were created via a robust ML classifier, support vector machine (SVM), while targeting best-estimate clinical diagnosis of ASD vs. non-ASD. Parameter settings were tuned in multiple levels of cross-validation. Results The created algorithms were more effective (higher performing) than current algorithms, were tunable (sensitivity and specificity can be differentially weighted), and were more efficient (achieving near-peak performance with five or fewer codes). Results from ML-based fusion of ADI-R and SRS are reported. We present a screener algorithm for below (above) age 10 that reached 89.2% (86.7%) sensitivity and 59.0% (53.4%) specificity with only five behavioral codes. Conclusions ML is useful for creating robust, customizable instrument algorithms. In a unique dataset comprised of controls with other difficulties, our findings highlight limitations of current caregiver-report instruments and indicate possible avenues for improving ASD screening and diagnostic tools. PMID:27090613

Use of machine learning to improve autism screening and diagnostic instruments: effectiveness, efficiency, and multi-instrument fusion.

PubMed

Bone, Daniel; Bishop, Somer L; Black, Matthew P; Goodwin, Matthew S; Lord, Catherine; Narayanan, Shrikanth S

2016-08-01

Machine learning (ML) provides novel opportunities for human behavior research and clinical translation, yet its application can have noted pitfalls (Bone et al., 2015). In this work, we fastidiously utilize ML to derive autism spectrum disorder (ASD) instrument algorithms in an attempt to improve upon widely used ASD screening and diagnostic tools. The data consisted of Autism Diagnostic Interview-Revised (ADI-R) and Social Responsiveness Scale (SRS) scores for 1,264 verbal individuals with ASD and 462 verbal individuals with non-ASD developmental or psychiatric disorders, split at age 10. Algorithms were created via a robust ML classifier, support vector machine, while targeting best-estimate clinical diagnosis of ASD versus non-ASD. Parameter settings were tuned in multiple levels of cross-validation. The created algorithms were more effective (higher performing) than the current algorithms, were tunable (sensitivity and specificity can be differentially weighted), and were more efficient (achieving near-peak performance with five or fewer codes). Results from ML-based fusion of ADI-R and SRS are reported. We present a screener algorithm for below (above) age 10 that reached 89.2% (86.7%) sensitivity and 59.0% (53.4%) specificity with only five behavioral codes. ML is useful for creating robust, customizable instrument algorithms. In a unique dataset comprised of controls with other difficulties, our findings highlight the limitations of current caregiver-report instruments and indicate possible avenues for improving ASD screening and diagnostic tools. © 2016 Association for Child and Adolescent Mental Health.

Increased Sensitivity of Diagnostic Mutation Detection by Re-analysis Incorporating Local Reassembly of Sequence Reads.

PubMed

Watson, Christopher M; Camm, Nick; Crinnion, Laura A; Clokie, Samuel; Robinson, Rachel L; Adlard, Julian; Charlton, Ruth; Markham, Alexander F; Carr, Ian M; Bonthron, David T

2017-12-01

Diagnostic genetic testing programmes based on next-generation DNA sequencing have resulted in the accrual of large datasets of targeted raw sequence data. Most diagnostic laboratories process these data through an automated variant-calling pipeline. Validation of the chosen analytical methods typically depends on confirming the detection of known sequence variants. Despite improvements in short-read alignment methods, current pipelines are known to be comparatively poor at detecting large insertion/deletion mutations. We performed clinical validation of a local reassembly tool, ABRA (assembly-based realigner), through retrospective reanalysis of a cohort of more than 2000 hereditary cancer cases. ABRA enabled detection of a 96-bp deletion, 4-bp insertion mutation in PMS2 that had been initially identified using a comparative read-depth approach. We applied an updated pipeline incorporating ABRA to the entire cohort of 2000 cases and identified one previously undetected pathogenic variant, a 23-bp duplication in PTEN. We demonstrate the effect of read length on the ability to detect insertion/deletion variants by comparing HiSeq2500 (2 × 101-bp) and NextSeq500 (2 × 151-bp) sequence data for a range of variants and thereby show that the limitations of shorter read lengths can be mitigated using appropriate informatics tools. This work highlights the need for ongoing development of diagnostic pipelines to maximize test sensitivity. We also draw attention to the large differences in computational infrastructure required to perform day-to-day versus large-scale reprocessing tasks.

Nested-PCR and a new ELISA-based NovaLisa test kit for malaria diagnosis in an endemic area of Thailand.

PubMed

Thongdee, Pimwan; Chaijaroenkul, Wanna; Kuesap, Jiraporn; Na-Bangchang, Kesara

2014-08-01

Microscopy is considered as the gold standard for malaria diagnosis although its wide application is limited by the requirement of highly experienced microscopists. PCR and serological tests provide efficient diagnostic performance and have been applied for malaria diagnosis and research. The aim of this study was to investigate the diagnostic performance of nested PCR and a recently developed an ELISA-based new rapid diagnosis test (RDT), NovaLisa test kit, for diagnosis of malaria infection, using microscopic method as the gold standard. The performance of nested-PCR as a malaria diagnostic tool is excellent with respect to its high accuracy, sensitivity, specificity, and ability to discriminate Plasmodium species. The sensitivity and specificity of nested-PCR compared with the microscopic method for detection of Plasmodium falciparum, Plasmodium vivax, and P. falciparum/P. vivax mixed infection were 71.4 vs 100%, 100 vs 98.7%, and 100 vs 95.0%, respectively. The sensitivity and specificity of the ELISA-based NovaLisa test kit compared with the microscopic method for detection of Plasmodium genus were 89.0 vs 91.6%, respectively. NovaLisa test kit provided comparable diagnostic performance. Its relatively low cost, simplicity, and rapidity enables large scale field application.

Applied Genomics: Data Mining Reveals Species-Specific Malaria Diagnostic Targets More Sensitive than 18S rRNA▿†‡

PubMed Central

Demas, Allison; Oberstaller, Jenna; DeBarry, Jeremy; Lucchi, Naomi W.; Srinivasamoorthy, Ganesh; Sumari, Deborah; Kabanywanyi, Abdunoor M.; Villegas, Leopoldo; Escalante, Ananias A.; Kachur, S. Patrick; Barnwell, John W.; Peterson, David S.; Udhayakumar, Venkatachalam; Kissinger, Jessica C.

2011-01-01

Accurate and rapid diagnosis of malaria infections is crucial for implementing species-appropriate treatment and saving lives. Molecular diagnostic tools are the most accurate and sensitive method of detecting Plasmodium, differentiating between Plasmodium species, and detecting subclinical infections. Despite available whole-genome sequence data for Plasmodium falciparum and P. vivax, the majority of PCR-based methods still rely on the 18S rRNA gene targets. Historically, this gene has served as the best target for diagnostic assays. However, it is limited in its ability to detect mixed infections in multiplex assay platforms without the use of nested PCR. New diagnostic targets are needed. Ideal targets will be species specific, highly sensitive, and amenable to both single-step and multiplex PCRs. We have mined the genomes of P. falciparum and P. vivax to identify species-specific, repetitive sequences that serve as new PCR targets for the detection of malaria. We show that these targets (Pvr47 and Pfr364) exist in 14 to 41 copies and are more sensitive than 18S rRNA when utilized in a single-step PCR. Parasites are routinely detected at levels of 1 to 10 parasites/μl. The reaction can be multiplexed to detect both species in a single reaction. We have examined 7 P. falciparum strains and 91 P. falciparum clinical isolates from Tanzania and 10 P. vivax strains and 96 P. vivax clinical isolates from Venezuela, and we have verified a sensitivity and specificity of ∼100% for both targets compared with a nested 18S rRNA approach. We show that bioinformatics approaches can be successfully applied to identify novel diagnostic targets and improve molecular methods for pathogen detection. These novel targets provide a powerful alternative molecular diagnostic method for the detection of P. falciparum and P. vivax in conventional or multiplex PCR platforms. PMID:21525225

Comparison of novel and standard diagnostic tools for the detection of Schistosoma mekongi infection in Lao People's Democratic Republic and Cambodia.

PubMed

Vonghachack, Youthanavanh; Sayasone, Somphou; Khieu, Virak; Bergquist, Robert; van Dam, Govert J; Hoekstra, Pytsje T; Corstjens, Paul L A M; Nickel, Beatrice; Marti, Hanspeter; Utzinger, Jürg; Muth, Sinuon; Odermatt, Peter

2017-08-10

Given the restricted distribution of Schistosoma mekongi in one province in Lao People's Democratic Republic (Lao PDR) and two provinces in Cambodia, together with progress of the national control programmes aimed at reducing morbidity and infection prevalence, the elimination of schistosomiasis mekongi seems feasible. However, sensitive diagnostic tools will be required to determine whether elimination has been achieved. We compared several standard and novel diagnostic tools in S. mekongi-endemic areas. The prevalence and infection intensity of S. mekongi were evaluated in 377 study participants from four villages in the endemic areas in Lao PDR and Cambodia using Kato-Katz stool examination, antibody detection based on an enzyme-linked immunosorbent assay (ELISA) and schistosome circulating antigen detection by lateral-flow tests. Two highly sensitive test systems for the detection of cathodic and anodic circulating antigens (CCA, CAA) in urine and serum were utilized. Stool microscopy revealed an overall prevalence of S. mekongi of 6.4% (one case in Cambodia and 23 cases in Lao PDR), while that of Opisthorchis viverrini, hookworm, Trichuris trichiura, Ascaris lumbricoides and Taenia spp. were 50.4%, 28.1%, 3.5%, 0.3% and 1.9%, respectively. In the urine samples, the tests for CCA and CAA detected S. mekongi infections in 21.0% and 38.7% of the study participants, respectively. In the serum samples, the CAA assay revealed a prevalence of 32.4%, while a combination of the CAA assay in serum and in urine revealed a prevalence of 43.2%. There was a difference between the two study locations with a higher prevalence reached in the samples from Lao PDR. The CCA, CAA and ELISA results showed substantially higher prevalence estimates for S. mekongi compared to Kato-Katz thick smears. Active schistosomiasis mekongi in Lao PDR and Cambodia might thus have been considerably underestimated previously. Hence, sustained control efforts are still needed to break transmission of S. mekongi. The pivotal role of highly sensitive diagnostic assays in areas targeting elimination cannot be overemphasised.

Application of Heart Rate Variability in Diagnosis and Prognosis of Individuals with Diabetes Mellitus: Systematic Review.

PubMed

França da Silva, Anne Kastelianne; Penachini da Costa de Rezende Barbosa, Marianne; Marques Vanderlei, Franciele; Destro Christofaro, Diego Giuliano; Marques Vanderlei, Luiz Carlos

2016-05-01

The use of heart rate variability as a tool capable of discriminating individuals with diabetes mellitus is still little explored, as its use has been limited to comparing those with and without the disease. Thus, the purpose of this study was to verify the use of heart rate variability as a tool for diagnostic and prognostic evaluation in person with diabetes and to identify whether there are cutoff points generated from the use of this tool in these individuals. A search was conducted in the electronic databases MEDLINE, Cochrane Library, Web of Science, EMBASE, and LILACS starting from the oldest records until January 2015, by means of descriptors related to the target condition, evaluated tool, and evaluation method. All the studies were evaluated for methodological quality using the QUADAS-2 instrument. Eight studies were selected. In general, the studies showed that the heart rate variability is useful to discriminate cardiac autonomic neuropathy in person with diabetes, and the sample entropy, SD1/SD2 indices, SDANN, HF, and slope of TFC have better discriminatory power to detect autonomic dysfunction, with sensitivity and specificity values ranging from 72% to 100% and 71% to 97%, respectively. Although there are methodological differences in indices used, in general, this tool demonstrated good sensitivity and specificity and can be used as an additional and/or complementary tool to the conventional autonomic tests, in order to obtain safer and more effective diagnostic, collaborating for better risk stratification conditions of these patients. © 2016 Wiley Periodicals, Inc.

18F-FDG-PET/CT Angiography for the Diagnosis of Infective Endocarditis.

PubMed

Roque, A; Pizzi, M N; Cuéllar-Calàbria, H; Aguadé-Bruix, S

2017-02-01

This article reviews the current imaging role of 18 F-fluordeoxyglucose positron emission computed tomography ( 18 F-FDG-PET/CT) combined with cardiac CT angiography (CTA) in infective endocarditis and discusses the strengths and limitations of this technique. The diagnosis of infective endocarditis affecting prosthetic valves and intracardiac devices is challenging because echocardiography and, therefore, the modified Duke criteria have well-recognized limitations in this clinical scenario. The high sensitivity of 18 F-FDG-PET/CT for the detection of infection associated with the accurate definition of structural damage by gated cardiac CTA in a combined technique (PET/CTA) has provided a significant increase in diagnostic sensitivity for the detection of IE. PET/CTA has proven to be a useful diagnostic tool in patients with suspected infective endocarditis. The additional information provided by this technique improves diagnostic performance in prosthetic valve endocarditis when it is used in combination with the Duke criteria. The findings obtained in PET/CTA studies have been included as a major criterion in the recently updated diagnostic algorithm in infective endocarditis guidelines.

Advanced DNA-Based Point-of-Care Diagnostic Methods for Plant Diseases Detection.

PubMed

Lau, Han Yih; Botella, Jose R

2017-01-01

Diagnostic technologies for the detection of plant pathogens with point-of-care capability and high multiplexing ability are an essential tool in the fight to reduce the large agricultural production losses caused by plant diseases. The main desirable characteristics for such diagnostic assays are high specificity, sensitivity, reproducibility, quickness, cost efficiency and high-throughput multiplex detection capability. This article describes and discusses various DNA-based point-of care diagnostic methods for applications in plant disease detection. Polymerase chain reaction (PCR) is the most common DNA amplification technology used for detecting various plant and animal pathogens. However, subsequent to PCR based assays, several types of nucleic acid amplification technologies have been developed to achieve higher sensitivity, rapid detection as well as suitable for field applications such as loop-mediated isothermal amplification, helicase-dependent amplification, rolling circle amplification, recombinase polymerase amplification, and molecular inversion probe. The principle behind these technologies has been thoroughly discussed in several review papers; herein we emphasize the application of these technologies to detect plant pathogens by outlining the advantages and disadvantages of each technology in detail.

Advanced DNA-Based Point-of-Care Diagnostic Methods for Plant Diseases Detection

PubMed Central

Lau, Han Yih; Botella, Jose R.

2017-01-01

Diagnostic technologies for the detection of plant pathogens with point-of-care capability and high multiplexing ability are an essential tool in the fight to reduce the large agricultural production losses caused by plant diseases. The main desirable characteristics for such diagnostic assays are high specificity, sensitivity, reproducibility, quickness, cost efficiency and high-throughput multiplex detection capability. This article describes and discusses various DNA-based point-of care diagnostic methods for applications in plant disease detection. Polymerase chain reaction (PCR) is the most common DNA amplification technology used for detecting various plant and animal pathogens. However, subsequent to PCR based assays, several types of nucleic acid amplification technologies have been developed to achieve higher sensitivity, rapid detection as well as suitable for field applications such as loop-mediated isothermal amplification, helicase-dependent amplification, rolling circle amplification, recombinase polymerase amplification, and molecular inversion probe. The principle behind these technologies has been thoroughly discussed in several review papers; herein we emphasize the application of these technologies to detect plant pathogens by outlining the advantages and disadvantages of each technology in detail. PMID:29375588

Lichtheimia Infection in a Lymphoma Patient: Case Report and a Brief Review of the Available Diagnostic Tools.

PubMed

Zimmerli, Stefan; Bialek, Ralf; Blau, Igor W; Christe, Andreas; Lass-Flörl, Cornelia; Presterl, Elisabeth

2016-08-01

We describe the case of a patient with a T-lymphoblastic lymphoma whose disseminated mucormycosis was diagnosed with delay, and we address the diagnostic and therapeutic decision-making process and review the diagnostic workup of patients with potential IFD. The diagnosis was delayed despite a suggestive radiological presentation of the patient's pulmonary lesion. The uncommon risk profile (T-lymphoblastic lymphoma, short neutropenic phases) wrongly led to a low level of suspicion. The diagnosis was also hampered by the lack of indirect markers for infections caused by Mucorales, the low sensitivity of both fungal culture and panfungal PCR, and the limited availability of species-specific PCR. A high level of suspicion of IFD is needed, and aggressive diagnostic procedures should be promptly initiated even in apparently low-risk patients with uncommon presentations. The extent of the analytical workup should be decided on a case-by-case base. Diagnostic tests such as the galactomannan and β-D-glucan test and/or PCR on biological material followed by sequencing should be chosen according to their availability and after evaluation of their specificity and sensitivity. In high-risk patients, preemptive therapy with a broad-spectrum mould-active antifungal agent should be started before definitive diagnostic findings become available.

Diagnostic performance of 64-slice multidetector coronary computed tomographic angiography in women.

PubMed

Jug, Borut; Gupta, Mohit; Papazian, Jenny; Li, Dong; Tsang, Janet; Bhatia, Harpreet; Karlsberg, Ronald; Budoff, Matthew

2012-12-01

Diagnostic approach to chest pain in women is challenging, but still under-investigated. The purpose of this study was to assess the diagnostic performance of 64-slice multidetector coronary computed tomographic angiography (CCTA) in women with chest pain. We included 606 patients--255 women and 351 men (mean age 61 ± 12 years for both)--who had been referred for a CCTA and an invasive coronary angiography (diagnostic standard) because of chest pain, either as part of clinical work-up in two urban medical centers or as part of the multicenter ACCURACY trial. On a patient-based model, the sensitivity, specificity, and positive predictive value (PPV) and negative predictive value to detect ≥50% and ≥70% stenosis were 98%, 84%, 87%, and 97% and 96%, 83%, 77%, and 97%, respectively, for women and 97%, 83%, 89%, and 95% and 94%, 91%, 90%, and 94%, respectively, for men. There were no statistically significant differences between men and women in diagnostic performance measures except for the PPV of detecting a ≥70% stenosis (P = .007). In women with chest pain, 64-slice multidetector CCTA is at least as sensitive and specific as in men. Our findings suggest that CCTA is a promising diagnostic tool for timely detection and/or exclusion of CAD in symptomatic intermediate-risk female populations.

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.

Diagnostic accuracy of fundal height and handheld ultrasound-measured abdominal circumference to screen for fetal growth abnormalities

PubMed Central

Haragan, Adriane F.; Hulsey, Thomas C.; Hawk, Angela F.; Newman, Roger B.; Chang, Eugene Y.

2015-01-01

OBJECTIVE We sought to compare fundal height and handheld ultrasound–measured fetal abdominal circumference (HHAC) for the prediction of fetal growth restriction (FGR) or large for gestational age. STUDY DESIGN This was a diagnostic accuracy study in nonanomalous singleton pregnancies between 24 and 40 weeks’ gestation. Patients underwent HHAC and fundal height measurement prior to formal growth ultrasound. FGR was defined as estimated fetal weight less than 10%, whereas large for gestational age was defined as estimated fetal weight greater than 90%. Sensitivity and specificity were calculated and compared using methods described elsewhere. RESULTS There were 251 patients included in this study. HHAC had superior sensitivity and specificity for the detection of FGR (sensitivity, 100% vs 42.86%) and (specificity, 92.62% vs 85.24%). HHAC had higher specificity but lower sensitivity when screening for LGA (specificity, 85.66% vs 66.39%) and (sensitivity, 57.14% vs 71.43%). CONCLUSION HHAC could prove to be a valuable screening tool in the detection of FGR. Further studies are needed in a larger population. PMID:25818672

Field evaluation of the photo-induced electron transfer fluorogenic primers (PET) real-time PCR for the detection of Plasmodium falciparum in Tanzania.

PubMed

Talundzic, Eldin; Maganga, Mussa; Masanja, Irene M; Peterson, David S; Udhayakumar, Venkatachalam; Lucchi, Naomi W

2014-01-27

Accurate diagnosis of malaria infections remains challenging, especially in the identification of submicroscopic infections. New molecular diagnostic tools that are inexpensive, sensitive enough to detect low-level infections and suitable in laboratory settings of resource-limited countries are required for malaria control and elimination programmes. Here the diagnostic potential of a recently developed photo-induced electron transfer fluorogenic primer (PET) real-time polymerase chain reaction (PCR) called PET-PCR was investigated. This study aimed to (i) evaluate the use of this assay as a method for the detection of both Plasmodium falciparum and other Plasmodium species infections in a developing country's diagnostic laboratory; and, (ii) determine the assay's sensitivity and specificity compared to a nested 18S rRNA PCR. Samples used in this study were obtained from a previous study conducted in the region of Iringa, Tanzania. A total of 303 samples from eight health facilities in Tanzania were utilized for this evaluation. All samples were screened using the multiplex PET-PCR assay designed to detect Plasmodium genus and P. falciparum initially in laboratory in Tanzania and then repeated at a reference laboratory at the CDC in the USA. Microscopy data was available for all the 303 samples. A subset of the samples were tested in a blinded fashion to find the sensitivity and specificity of the PET-PCR compared to the nested 18S rRNA PCR. Compared to microscopy, the PET-PCR assay was 59% more sensitive in detecting P. falciparum infections. The observed sensitivity and specificity were 100% (95% confidence interval (CI0.95) = 94-100%) and (CI0.95 = 96-100%), respectively, for the PET-PCR assay when compared to nested 18S rRNA PCR. When compared to 18S rRNA PCR, microscopy had a low sensitivity of 40% (CI0.95 = 23-61%) and specificity of 100% (CI0.95 = 96-100%). The PET-PCR results performed in the field laboratory in Tanzania were in 100% concordance with the results obtained at the reference laboratory in the USA. The PET-PCR is a new molecular diagnostic tool with similar performance characteristics as commonly used PCR methods that is less expensive, easy to use, and amiable to large scale-surveillance studies in developing country settings.

Diagnosing schistosomiasis: where are we?

PubMed

Gomes, Luciana Inácia; Enk, Martin Johannes; Rabello, Ana

2014-01-01

In light of the World Health Organization's initiative to extend schistosomiasis morbidity and mortality control programs by including a disease elimination strategy in low endemic settings, this paper reviews diagnostic tools described during the last decades and provide an overview of ongoing efforts in making an efficient diagnostic tool available worldwide. A literature search on PubMed using the search criteria schistosomiasis and diagnosis within the period from 1978 to 2013 was carried out. Articles with abstract in English and that used laboratory techniques specifically developed for the detection of schistosomiasis in humans were included. Publications were categorized according to the methodology applied (parasitological, immunological, or molecular) and stage of development (in house development, limited field, or large scale field testing). The initial research generated 4,535 publications, of which only 643 met the inclusion criteria. The vast majority (537) of the publications focused on immunological techniques; 81 focused on parasitological diagnosis, and 25 focused on molecular diagnostic methods. Regarding the stage of development, 307 papers referred to in-house development, 202 referred to limited field tests, and 134 referred to large scale field testing. The data obtained show that promising new diagnostic tools, especially for Schistosoma antigen and deoxyribonucleic acid (DNA) detection, which are characterized by high sensitivity and specificity, are being developed. In combination with international funding initiatives these tools may result in a significant step forward in successful disease elimination and surveillance, which is to make efficient tests accessible and its large use self-sustainable for control programs in endemic countries.

Molecular malaria diagnostics: A systematic review and meta-analysis.

PubMed

Roth, Johanna M; Korevaar, Daniël A; Leeflang, Mariska M G; Mens, Pètra F

2016-01-01

Accurate diagnosis of malaria is essential for identification and subsequent treatment of the disease. Currently, microscopy and rapid diagnostic tests are the most commonly used diagnostics, next to treatment based on clinical signs only. These tests are easy to deploy, but have a relatively high detection limit. With declining prevalence in many areas, there is an increasing need for more sensitive diagnostics. Molecular tools may be a suitable alternative, although costs and technical requirements currently hamper their implementation in resource limited settings. A range of (near) point-of-care diagnostics is therefore under development, including simplifications in sample preparation, amplification and/or read-out of the test. Accuracy data, in combination with technical characteristics, are essential in determining which molecular test, if any, would be the most promising to be deployed. This review presents a comprehensive overview of the currently available molecular malaria diagnostics, ranging from well-known tests to platforms in early stages of evaluation, and systematically evaluates their published accuracy. No important difference in accuracy was found between the most commonly used PCR-based assays (conventional, nested and real-time PCR), with most of them having high sensitivity and specificity, implying that there are no reasons other than practical ones to choose one technique over the other. Loop-mediated isothermal amplification and other (novel) diagnostics appear to be highly accurate as well, with some offering potential to be used in resource-limited settings.

Assessment of Mycobacterium tuberculosis OmpATb as a Novel Antigen for the Diagnosis of Bovine Tuberculosis

USDA-ARS?s Scientific Manuscript database

In search for improved tools to control bovine tuberculosis, the development of diagnostic tests with improved specificity and sensitivity has a high priority. Such tests require the identification of enhanced immunodiagnostic reagents. In this study, we evaluated the potential of Rv0899 (Outer memb...

Efficiency of the Bethesda System for Thyroid Cytopathology.

PubMed

Mora-Guzmán, Ismael; Muñoz de Nova, José Luis; Marín-Campos, Cristina; Jiménez-Heffernan, José Antonio; Cuesta Pérez, Juan Julián; Lahera Vargas, Marcos; Torres Mínguez, Emma; Martín-Pérez, Elena

2018-03-28

Fine-needle aspiration biopsies are a key tool for preoperative assessment of thyroid nodules, and the Bethesda system is the preferred method to report cytological analysis. The purpose of this study is to assess the efficiency of the Bethesda system to identify the malignancy risk of thyroid nodules. Patients who underwent thyroid surgery between June 2010 and June 2017 were included. Samples were classified into 6categories according to rates of malignancy associated with each diagnostic category. In order to investigate the correlation between categories, a statistical analysis compared the categories with pathology reports. Diagnostic indicators were calculated as a screening test (categories IV, V, VI as true-positive) and as a method to identify malignancy (V, VI as true-positive). In a series of 522 patients, we found 184 (35.2%) malignant tumours, papillary carcinoma being the most prevalent with 155 cases (84.2%). Malignant rates for diagnostic categories were: I, 0%; II, 1.5%; III, 6.4%; IV, 31%; V, 86.5%; VI, 100%. A robust correlation was identified between categories on statistical analysis. For the «screening test» analysis, sensitivity was 98.9%, specificity 84.4%, positive predictive value 69.6%, negative predictive value 99.5%, and diagnostic accuracy 88.2%. Analysing the accuracy to detect malignancy, values were: sensitivity 98.6%, specificity 97.6%, positive predictive value 93.5%, negative predictive value 99.5%, diagnostic accuracy 97.9%. The Bethesda system is a clear and reliable approach to report thyroid cytology and therefore is an effective tool to identify malignancy risk and guide clinical management. Copyright © 2018 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

A Meta-analysis for the Diagnostic Performance of Transient Elastography for Clinically Significant Portal Hypertension.

PubMed

You, Myung-Won; Kim, Kyung Won; Pyo, Junhee; Huh, Jimi; Kim, Hyoung Jung; Lee, So Jung; Park, Seong Ho

2017-01-01

We aimed to evaluate the correlation between liver stiffness measurement using transient elastography (TE-LSM) and hepatic venous pressure gradient and the diagnostic performance of TE-LSM in assessing clinically significant portal hypertension through meta-analysis. Eleven studies were included from thorough literature research and selection processes. The summary correlation coefficient was 0.783 (95% confidence interval [CI], 0.737-0.823). Summary sensitivity, specificity and area under the hierarchical summary receiver operating characteristic curve (AUC) were 87.5% (95% CI, 75.8-93.9%), 85.3 % (95% CI, 76.9-90.9%) and 0.9, respectively. The subgroup with low cut-off values of 13.6-18 kPa had better summary estimates (sensitivity 91.2%, specificity 81.3% and partial AUC 0.921) than the subgroup with high cut-off values of 21-25 kPa (sensitivity 71.2%, specificity 90.9% and partial AUC 0.769). In summary, TE-LSM correlated well with hepatic venous pressure gradient and represented good diagnostic performance in diagnosing clinically significant portal hypertension. For use as a sensitive screening tool, we propose using low cut-off values of 13.6-18 kPa in TE-LSM. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Point-of-care diagnostic assay for the detection of Zika virus using the recombinase polymerase amplification method.

PubMed

Vasileva Wand, Nadina I; Bonney, Laura C; Watson, Robert J; Graham, Victoria; Hewson, Roger

2018-06-13

The sudden and explosive expansion of Zika virus (ZIKV) from the African continent through Oceania and culminating in the outbreak in South America has highlighted the importance of new rapid point-of-care diagnostic tools for the control and prevention of transmission. ZIKV infection has devastating consequences, such as neurological congenital malformations in infants born to infected mothers and Guillain-Barré syndrome in adults. Additionally, its potential for transmission through vector bites, as well as from person to person through blood transfusions and sexual contact, are important considerations for prompt diagnosis. Recombinase polymerase amplification (RPA), an isothermal method, was developed as an alternative field-applicable assay to PCR. Here we report the development of a novel ZIKV real-time reverse transcriptase RPA (RT-RPA) assay capable of detecting a range of different ZIKV strains from a variety of geographical locations. The ZIKV RT-RPA was shown to be highly sensitive, being capable of detecting as few as five copies of target nucleic acid per reaction, and suitable for use with a battery-operated portable device. The ZIKV RT-RPA demonstrated 100 % specificity and 83 % sensitivity in clinical samples. Furthermore, we determined that the ZIKV RT-RPA is a versatile assay that can be applied to crude samples, such as saliva and serum, and can be used as a vector surveillance tool on crude mosquito homogenates. Therefore, the developed ZIKV RT-RPA is a useful diagnostic tool that can be transferred to a resource-limited location, eliminating the need for a specialized and sophisticated laboratory environment and highly trained staff.

Diagnostic accuracy of physical examination for anterior knee instability: a systematic review.

PubMed

Leblanc, Marie-Claude; Kowalczuk, Marcin; Andruszkiewicz, Nicole; Simunovic, Nicole; Farrokhyar, Forough; Turnbull, Travis Lee; Debski, Richard E; Ayeni, Olufemi R

2015-10-01

Determining diagnostic accuracy of Lachman, pivot shift and anterior drawer tests versus gold standard diagnosis (magnetic resonance imaging or arthroscopy) for anterior cruciate ligament (ACL) insufficiency cases. Secondarily, evaluating effects of: chronicity, partial rupture, awake versus anaesthetized evaluation. Searching MEDLINE, EMBASE and PubMed identified studies on diagnostic accuracy for ACL insufficiency. Studies identification and data extraction were performed in duplicate. Quality assessment used QUADAS tool, and statistical analyses were completed for pooled sensitivity and specificity. Eight studies were included. Given insufficient data, pooled analysis was only possible for sensitivity on Lachman and pivot shift test. During awake evaluation, sensitivity for the Lachman test was 89 % (95 % CI 0.76, 0.98) for all rupture types, 96 % (95 % CI 0.90, 1.00) for complete ruptures and 68 % (95 % CI 0.25, 0.98) for partial ruptures. For pivot shift in awake evaluation, results were 79 % (95 % CI 0.63, 0.91) for all rupture types, 86 % (95 % CI 0.68, 0.99) for complete ruptures and 67 % (95 % CI 0.47, 0.83) for partial ruptures. Decreased sensitivity of Lachman and pivot shift tests for partial rupture cases and for awake patients raised suspicions regarding the accuracy of these tests for diagnosis of ACL insufficiency. This may lead to further research aiming to improve the understanding of the true accuracy of these physical diagnostic tests and increase the reliability of clinical investigation for this pathology. IV.

Breast-specific gamma camera imaging with 99mTc-MIBI has better diagnostic performance than magnetic resonance imaging in breast cancer patients: A meta-analysis.

PubMed

Zhang, Aimi; Li, Panli; Liu, Qiufang; Song, Shaoli

2017-01-01

This study aimed to evaluate the diagnostic role of breast-specific gamma camera imaging (BSGI) with technetium-99m-methoxy isobutyl isonitrile ( 99m Tc-MIBI) and magnetic resonance imaging (MRI) in patients with breast cancer through a meta-analysis. Three reviewers searched articles published in medical journals before June 2016 in MEDLINE, EMBASE and Springer Databases; the references listed in original articles were also retrieved. We used the quality assessment of diagnostic accuracy studies (QUADAS) tool to assess the quality of the included studies. Heterogeneity, pooled sensitivity and specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR) and summary receiver operating characteristic (SROC) curves were calculated by Meta-DiSc software to estimate the diagnostic performance of BSGI and MRI. Ten studies with 517 patients were included after meeting the inclusion criteria. We did a subgroup analysis of the same data type. The pooled sensitivities of BSGI and MRI were: 0.84 (95% CI, 0.79-0.88) and 0.89 (95% CI, 0.84-0.92) respectively, and the pooled specificities of BSGI and MRI were: 0.82 (95% CI, 0.74-0.88) and 0.39 (95% CI, 0.30-0.49) respectively. The areas under the SROC curve of BSGI and MRI were 0.93 and 0.72 respectively. The results of our meta-analysis indicated that compared with MRI, BSGI has similar sensitivity, higher specificity, better diagnostic performance, and can be widely used in clinical practice.

The role of spectrophotometry in the diagnosis of melanoma.

PubMed

Ascierto, Paolo A; Palla, Marco; Ayala, Fabrizio; De Michele, Ileana; Caracò, Corrado; Daponte, Antonio; Simeone, Ester; Mori, Stefano; Del Giudice, Maurizio; Satriano, Rocco A; Vozza, Antonio; Palmieri, Giuseppe; Mozzillo, Nicola

2010-08-13

Spectrophotometry (SPT) could represent a promising technique for the diagnosis of cutaneous melanoma (CM) at earlier stages of the disease. Starting from our experience, we further assessed the role of SPT in CM early detection. During a health campaign for malignant melanoma at National Cancer Institute of Naples, we identified a subset of 54 lesions to be addressed to surgical excision and histological examination. Before surgery, all patients were investigated by clinical and epiluminescence microscopy (ELM) screenings; selected lesions underwent spectrophotometer analysis. For SPT, we used a video spectrophotometer imaging system (Spectroshade MHT S.p.A., Verona, Italy). Among the 54 patients harbouring cutaneous pigmented lesions, we performed comparison between results from the SPT screening and the histological diagnoses as well as evaluation of both sensitivity and specificity in detecting CM using either SPT or conventional approaches. For all pigmented lesions, agreement between histology and SPT classification was 57.4%. The sensitivity and specificity of SPT in detecting melanoma were 66.6% and 76.2%, respectively. Although SPT is still considered as a valuable diagnostic tool for CM, its low accuracy, sensitivity, and specificity represent the main hamper for the introduction of such a methodology in clinical practice. Dermoscopy remains the best diagnostic tool for the preoperative diagnosis of pigmented skin lesions.

Molecular diagnosis of Plasmodium ovale by photo-induced electron transfer fluorogenic primers: PET-PCR

PubMed Central

Akerele, David; Ljolje, Dragan; Talundzic, Eldin; Udhayakumar, Venkatachalam

2017-01-01

Accurate diagnosis of malaria infections continues to be challenging and elusive, especially in the detection of submicroscopic infections. Developing new malaria diagnostic tools that are sensitive enough to detect low-level infections, user friendly, cost effective and capable of performing large scale diagnosis, remains critical. We have designed novel self-quenching photo-induced electron transfer (PET) fluorogenic primers for the detection of P. ovale by real-time PCR. In our study, a total of 173 clinical samples, consisting of different malaria species, were utilized to test this novel PET-PCR primer. The sensitivity and specificity were calculated using nested-PCR as the reference test. The novel primer set demonstrated a sensitivity of 97.5% and a specificity of 99.2% (95% CI 85.2–99.8% and 95.2–99.9% respectively). Furthermore, the limit of detection for P. ovale was found to be 1 parasite/μl. The PET-PCR assay is a new molecular diagnostic tool with comparable performance to other commonly used PCR methods. It is relatively easy to perform, and amiable to large scale malaria surveillance studies and malaria control and elimination programs. Further field validation of this novel primer will be helpful to ascertain the utility for large scale malaria screening programs. PMID:28640824

Molecular diagnosis of Plasmodium ovale by photo-induced electron transfer fluorogenic primers: PET-PCR.

PubMed

Akerele, David; Ljolje, Dragan; Talundzic, Eldin; Udhayakumar, Venkatachalam; Lucchi, Naomi W

2017-01-01

Accurate diagnosis of malaria infections continues to be challenging and elusive, especially in the detection of submicroscopic infections. Developing new malaria diagnostic tools that are sensitive enough to detect low-level infections, user friendly, cost effective and capable of performing large scale diagnosis, remains critical. We have designed novel self-quenching photo-induced electron transfer (PET) fluorogenic primers for the detection of P. ovale by real-time PCR. In our study, a total of 173 clinical samples, consisting of different malaria species, were utilized to test this novel PET-PCR primer. The sensitivity and specificity were calculated using nested-PCR as the reference test. The novel primer set demonstrated a sensitivity of 97.5% and a specificity of 99.2% (95% CI 85.2-99.8% and 95.2-99.9% respectively). Furthermore, the limit of detection for P. ovale was found to be 1 parasite/μl. The PET-PCR assay is a new molecular diagnostic tool with comparable performance to other commonly used PCR methods. It is relatively easy to perform, and amiable to large scale malaria surveillance studies and malaria control and elimination programs. Further field validation of this novel primer will be helpful to ascertain the utility for large scale malaria screening programs.

The role of spectrophotometry in the diagnosis of melanoma

PubMed Central

2010-01-01

Background Spectrophotometry (SPT) could represent a promising technique for the diagnosis of cutaneous melanoma (CM) at earlier stages of the disease. Starting from our experience, we further assessed the role of SPT in CM early detection. Methods During a health campaign for malignant melanoma at National Cancer Institute of Naples, we identified a subset of 54 lesions to be addressed to surgical excision and histological examination. Before surgery, all patients were investigated by clinical and epiluminescence microscopy (ELM) screenings; selected lesions underwent spectrophotometer analysis. For SPT, we used a video spectrophotometer imaging system (Spectroshade® MHT S.p.A., Verona, Italy). Results Among the 54 patients harbouring cutaneous pigmented lesions, we performed comparison between results from the SPT screening and the histological diagnoses as well as evaluation of both sensitivity and specificity in detecting CM using either SPT or conventional approaches. For all pigmented lesions, agreement between histology and SPT classification was 57.4%. The sensitivity and specificity of SPT in detecting melanoma were 66.6% and 76.2%, respectively. Conclusions Although SPT is still considered as a valuable diagnostic tool for CM, its low accuracy, sensitivity, and specificity represent the main hamper for the introduction of such a methodology in clinical practice. Dermoscopy remains the best diagnostic tool for the preoperative diagnosis of pigmented skin lesions. PMID:20707921

Highly sensitive immunoassay of anti-cyclic citrullinated peptide marker using surface-enhanced Raman scattering detection

NASA Astrophysics Data System (ADS)

Chon, H.; Lee, S.; Wang, R.; Bang, S.-Y.; Lee, H.-S.; Bae, S.-C.; Hong, S. H.; Yoon, Y. H.; Lim, D.; Choo, J.

2015-07-01

We report a highly sensitive anti-cyclic citrullinated peptide (anti-CCP) detection method for early diagnosis of rheumatoid arthritis (RA) using surface-enhanced Raman scattering (SERS)-based immunoassay. Herein, cyclic citrullinated peptide (CCP)-conjugated magnetic beads and anti-human IgG-conjugated hollow gold nanospheres (HGNs) were used as substrates and SERS nano-tags, respectively. First, its detection sensitivity was evaluated using anti-CCP standard solutions. Then quantitative anti-CCP levels, determined by the SERS-based assay, were compared with those obtained from three commercially available anti-CCP assay kits (Immunoscan CCPlus, ImmunnLisa™ CCP and BioPlex™ 2200) to assess its potential utility as a clinical tool. Finally, clinical samples from 20 RA patients were investigated using them. In the SERS-based assay, the anti-CCP level in human serum was successfully determined by monitoring the characteristic Raman peak intensity of SERS nano-tags. The diagnostic performance of our SERS-based immunoassay for clinical samples shows a good agreement with those measured by three commercial anti-CCP kits. In addition, our SERS-based assay results are more consistent in the low concentration range (0-25 U/mL) than those achieved by the commercial kits. Accordingly, it is estimated that the SERS-based assay is a potentially useful diagnostic tool for early diagnosis of RA.

Diagnostic Performance of Narrow Band Imaging for Laryngeal Cancer: A Systematic Review and Meta-analysis.

PubMed

Sun, Changling; Han, Xue; Li, Xiaoying; Zhang, Yayun; Du, Xiaodong

2017-04-01

Objective To evaluate the performance of narrow band imaging (NBI) for the diagnosis of laryngeal cancer and to compare the diagnostic value of NBI with that of white light endoscopy. Data Sources PubMed, Embase, Cochrane Library, and CNKI databases. Review Methods Data analyses were performed with Meta-DiSc. The updated Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess study quality and potential bias. Publication bias was assessed with the Deeks's asymmetry test. The protocol used in this article has been published on PROSPERO and is in accordance with the PRISMA checklist. The registry number for this study is CRD42015025866. Results Six studies including 716 lesions were included in this meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratio for the NBI diagnosis of laryngeal cancer were 0.94 (95% confidence interval [95% CI]: 0.91-0.96), 0.89 (95% CI: 0.85-0.92), and 142.12 (95% CI: 46.42-435.15), respectively, and the area under receiver operating characteristics curve was 0.97. Among the 6 studies, 3 evaluated the diagnostic value of white light endoscopy, with a sensitivity of 0.81 (95% CI: 0.76-0.86), a specificity of 0.92 (95% CI: 0.88-0.95), and a diagnostic odds ratio of 33.82 (95% CI: 14.76-77.49). The evaluation of heterogeneity, calculated per the diagnostic odds ratio, gave an I 2 of 66%. No marked publication bias ( P = .84) was detected in this meta-analysis. Conclusion The sensitivity of NBI is superior to white light endoscopy, and the potential value of NBI needs to be validated in future studies.

The diagnostic value of pepsin detection in saliva for gastro-esophageal reflux disease: a preliminary study from China.

PubMed

Du, Xing; Wang, Feng; Hu, Zhiwei; Wu, Jimin; Wang, Zhonggao; Yan, Chao; Zhang, Chao; Tang, Juan

2017-10-17

None of current diagnostic methods has been proven to be a reliable tool for gastro-esophageal reflux disease (GERD). Pepsin in saliva has been proposed as a promising diagnostic biomarker for gastro-esophageal reflux. We aimed to determine the diagnostic value of salivary pepsin detection for GERD. Two hundred and fifty patients with symptoms suggestive of GERD and 35 asymptomatic healthy volunteers provided saliva on morning waking, after lunch and dinner for pepsin determination using the Peptest lateral flow device. All patients underwent 24-h multichannel intraluminal impedance pH (24-h MII-pH) monitoring and upper gastrointestinal endoscopy. Based on 24-h MII-pH and endoscopy study, patients were defined as GERD (abnormal MII-pH results and/or reflux esophagitis) and non-GERD otherwise. Patients with GERD had a higher prevalence of pepsin in saliva and higher pepsin concentration than patients with non-GERD and healthy controls (P < 0.001 for all). The pepsin test had a sensitivity of 73% and a specificity of 88.3% for diagnosing GERD using the optimal cut-off value of 76 ng/mL. Postprandial saliva samples collected when the symptoms occurred had a more powerful ability to identify GERD. Salivary pepsin test had moderate diagnostic value for GERD. It may be a promising tool to replace the use of currently invasive tools with advantages of non-invasive, easy to perform and cost effective. ChiCTR-DDD-16009506 (date of registration: October 20, 2016).

The Usefulness of Rapid Diagnostic Tests in the New Context of Low Malaria Transmission in Zanzibar

PubMed Central

Shakely, Delér; Msellem, Mwinyi I.; Morris, Ulrika; Omar, Rahila; Weiping, Xu; Petzold, Max; Greenhouse, Bryan; Baltzell, Kimberly A.; Ali, Abdullah S.; Björkman, Anders; Mårtensson, Andreas

2013-01-01

Background We assessed if histidine-rich-protein-2 (HRP2) based rapid diagnostic test (RDT) remains an efficient tool for Plasmodium falciparum case detection among fever patients in Zanzibar and if primary health care workers continue to adhere to RDT results in the new epidemiological context of low malaria transmission. Further, we evaluated the performance of RDT within the newly adopted integrated management of childhood illness (IMCI) algorithm in Zanzibar. Methods and Findings We enrolled 3890 patients aged ≥2 months with uncomplicated febrile illness in this health facility based observational study conducted in 12 primary health care facilities in Zanzibar, between May-July 2010. One patient had an inconclusive RDT result. Overall 121/3889 (3.1%) patients were RDT positive. The highest RDT positivity rate, 32/528 (6.1%), was found in children aged 5–14 years. RDT sensitivity and specificity against PCR was 76.5% (95% CI 69.0–83.9%) and 99.9% (95% CI 99.7–100%), and against blood smear microscopy 78.6% (95% CI 70.8–85.1%) and 99.7% (95% CI 99.6–99.9%), respectively. All RDT positive, but only 3/3768 RDT negative patients received anti-malarial treatment. Adherence to RDT results was thus 3887/3889 (99.9%). RDT performed well in the IMCI algorithm with equally high adherence among children <5 years as compared with other age groups. Conclusions The sensitivity of HRP-2 based RDT in the hands of health care workers compared with both PCR and microscopy for P. falciparum case detection was relatively low, whereas adherence to test results with anti-malarial treatment was excellent. Moreover, the results provide evidence that RDT can be reliably integrated in IMCI as a tool for improved childhood fever management. However, the relatively low RDT sensitivity highlights the need for improved quality control of RDT use in primary health care facilities, but also for more sensitive point-of-care malaria diagnostic tools in the new epidemiological context of low malaria transmission in Zanzibar. Trial registration ClinicalTrials.gov NCT01002066 PMID:24023791

Diagnostics of underwater electrical wire explosion through a time- and space-resolved hard x-ray source

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

Sheftman, D.; Shafer, D.; Efimov, S.

2012-10-15

A time- and space-resolved hard x-ray source was developed as a diagnostic tool for imaging underwater exploding wires. A {approx}4 ns width pulse of hard x-rays with energies of up to 100 keV was obtained from the discharge in a vacuum diode consisting of point-shaped tungsten electrodes. To improve contrast and image quality, an external pulsed magnetic field produced by Helmholtz coils was used. High resolution x-ray images of an underwater exploding wire were obtained using a sensitive x-ray CCD detector, and were compared to optical fast framing images. Future developments and application of this diagnostic technique are discussed.

Diagnostics of underwater electrical wire explosion through a time- and space-resolved hard x-ray source.

PubMed

Sheftman, D; Shafer, D; Efimov, S; Gruzinsky, K; Gleizer, S; Krasik, Ya E

2012-10-01

A time- and space-resolved hard x-ray source was developed as a diagnostic tool for imaging underwater exploding wires. A ~4 ns width pulse of hard x-rays with energies of up to 100 keV was obtained from the discharge in a vacuum diode consisting of point-shaped tungsten electrodes. To improve contrast and image quality, an external pulsed magnetic field produced by Helmholtz coils was used. High resolution x-ray images of an underwater exploding wire were obtained using a sensitive x-ray CCD detector, and were compared to optical fast framing images. Future developments and application of this diagnostic technique are discussed.

Improved reliability of serological tools for the diagnosis of West Nile fever in horses within Europe

PubMed Central

Lowenski, Steeve; Durand, Benoit; Bahuon, Céline; Zientara, Stéphan; Lecollinet, Sylvie

2017-01-01

West Nile Fever is a zoonotic disease caused by a mosquito-borne flavivirus, WNV. By its clinical sensitivity to the disease, the horse is a useful sentinel of infection. Because of the virus’ low-level, short-term viraemia in horses, the primary tools used to diagnose WNV are serological tests. Inter-laboratory proficiency tests (ILPTs) were held in 2010 and 2013 to evaluate WNV serological diagnostic tools suited for the European network of National Reference Laboratories (NRLs) for equine diseases. These ILPTs were designed to evaluate the laboratories’ and methods’ performances in detecting WNV infection in horses through serology. The detection of WNV immunoglobulin G (IgG) antibodies by ELISA is widely used in Europe, with 17 NRLs in 2010 and 20 NRLs in 2013 using IgG WNV assays. Thanks to the development of new commercial IgM capture kits, WNV IgM capture ELISAs were rapidly implemented in NRLs between 2010 (4 NRLs) and 2013 (13 NRLs). The use of kits allowed the quick standardisation of WNV IgG and IgM detection assays in NRLs with more than 95% (20/21) and 100% (13/13) of satisfactory results respectively in 2013. Conversely, virus neutralisation tests (VNTs) were implemented in 33% (7/21) of NRLs in 2013 and their low sensitivity was evidenced in 29% (2/7) of NRLs during this ILPT. A comparison of serological diagnostic methods highlighted the higher sensitivity of IgG ELISAs compared to WNV VNTs. They also revealed that the low specificity of IgG ELISA kits meant that it could detect animals infected with other flaviviruses. In contrast VNT and IgM ELISA assays were highly specific and did not detect antibodies against related flaviviruses. These results argue in favour of the need for and development of new, specific serological diagnostic assays that could be easily transferred to partner laboratories. PMID:28915240

Synthetic biology devices for in vitro and in vivo diagnostics.

PubMed

Slomovic, Shimyn; Pardee, Keith; Collins, James J

2015-11-24

There is a growing need to enhance our capabilities in medical and environmental diagnostics. Synthetic biologists have begun to focus their biomolecular engineering approaches toward this goal, offering promising results that could lead to the development of new classes of inexpensive, rapidly deployable diagnostics. Many conventional diagnostics rely on antibody-based platforms that, although exquisitely sensitive, are slow and costly to generate and cannot readily confront rapidly emerging pathogens or be applied to orphan diseases. Synthetic biology, with its rational and short design-to-production cycles, has the potential to overcome many of these limitations. Synthetic biology devices, such as engineered gene circuits, bring new capabilities to molecular diagnostics, expanding the molecular detection palette, creating dynamic sensors, and untethering reactions from laboratory equipment. The field is also beginning to move toward in vivo diagnostics, which could provide near real-time surveillance of multiple pathological conditions. Here, we describe current efforts in synthetic biology, focusing on the translation of promising technologies into pragmatic diagnostic tools and platforms.

Synthetic biology devices for in vitro and in vivo diagnostics

PubMed Central

Slomovic, Shimyn; Pardee, Keith; Collins, James J.

2015-01-01

There is a growing need to enhance our capabilities in medical and environmental diagnostics. Synthetic biologists have begun to focus their biomolecular engineering approaches toward this goal, offering promising results that could lead to the development of new classes of inexpensive, rapidly deployable diagnostics. Many conventional diagnostics rely on antibody-based platforms that, although exquisitely sensitive, are slow and costly to generate and cannot readily confront rapidly emerging pathogens or be applied to orphan diseases. Synthetic biology, with its rational and short design-to-production cycles, has the potential to overcome many of these limitations. Synthetic biology devices, such as engineered gene circuits, bring new capabilities to molecular diagnostics, expanding the molecular detection palette, creating dynamic sensors, and untethering reactions from laboratory equipment. The field is also beginning to move toward in vivo diagnostics, which could provide near real-time surveillance of multiple pathological conditions. Here, we describe current efforts in synthetic biology, focusing on the translation of promising technologies into pragmatic diagnostic tools and platforms. PMID:26598662

Artificial neural networks for processing fluorescence spectroscopy data in skin cancer diagnostics

NASA Astrophysics Data System (ADS)

Lenhardt, L.; Zeković, I.; Dramićanin, T.; Dramićanin, M. D.

2013-11-01

Over the years various optical spectroscopic techniques have been widely used as diagnostic tools in the discrimination of many types of malignant diseases. Recently, synchronous fluorescent spectroscopy (SFS) coupled with chemometrics has been applied in cancer diagnostics. The SFS method involves simultaneous scanning of both emission and excitation wavelengths while keeping the interval of wavelengths (constant-wavelength mode) or frequencies (constant-energy mode) between them constant. This method is fast, relatively inexpensive, sensitive and non-invasive. Total synchronous fluorescence spectra of normal skin, nevus and melanoma samples were used as input for training of artificial neural networks. Two different types of artificial neural networks were trained, the self-organizing map and the feed-forward neural network. Histopathology results of investigated skin samples were used as the gold standard for network output. Based on the obtained classification success rate of neural networks, we concluded that both networks provided high sensitivity with classification errors between 2 and 4%.

Diagnostic accuracy of tests to detect Hepatitis C antibody: a meta-analysis and review of the literature.

PubMed

Tang, Weiming; Chen, Wen; Amini, Ali; Boeras, Debi; Falconer, Jane; Kelly, Helen; Peeling, Rosanna; Varsaneux, Olivia; Tucker, Joseph D; Easterbrook, Philippa

2017-11-01

Although direct-acting antivirals can achieve sustained virological response rates greater than 90% in Hepatitis C Virus (HCV) infected persons, at present the majority of HCV-infected individuals remain undiagnosed and therefore untreated. While there are a wide range of HCV serological tests available, there is a lack of formal assessment of their diagnostic performance. We undertook a systematic review and meta-analysis to evaluate he diagnostic accuracy of available rapid diagnostic tests (RDT) and laboratory based EIA assays in detecting antibodies to HCV. We used the PRISMA checklist and Cochrane guidance to develop our search protocol. The search strategy was registered in PROSPERO (CRD42015023567). The search focused on hepatitis C, diagnostic tests, and diagnostic accuracy within eight databases (MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Science Citation Index Expanded, Conference Proceedings Citation Index-Science, SCOPUS, Literatura Latino-Americana e do Caribe em Ciências da Saúde and WHO Global Index Medicus. Studies were included if they evaluated an assay to determine the sensitivity and specificity of HCV antibody (HCV Ab) in humans. Two reviewers independently extracted data and performed a quality assessment of the studies using the QUADAS tool. We pooled test estimates using the DerSimonian-Laird method, by using the software R and RevMan. 5.3. A total of 52 studies were identified that included 52,673 unique test measurements. Based on five studies, the pooled sensitivity and specificity of HCV Ab rapid diagnostic tests (RDTs) were 98% (95% CI 98-100%) and 100% (95% CI 100-100%) compared to an enzyme immunoassay (EIA) reference standard. High HCV Ab RDTs sensitivity and specificity were observed across screening populations (general population, high risk populations, and hospital patients) using different reference standards (EIA, nucleic acid testing, immunoblot). There were insufficient studies to undertake subanalyses based on HIV co-infection. Oral HCV Ab RDTs also had excellent sensitivity and specificity compared to blood reference tests, respectively at 94% (95% CI 93-96%) and 100% (95% CI 100-100%). Among studies that assessed individual oral RDTs, the eight studies revealed that OraQuick ADVANCE® had a slightly higher sensitivity (98%, 95% CI 97-98%) compared to the other oral brands (pooled sensitivity: 88%, 95% CI 84-92%). RDTs, including oral tests, have excellent sensitivity and specificity compared to laboratory-based methods for HCV antibody detection across a wide range of settings. Oral HCV Ab RDTs had good sensitivity and specificity compared to blood reference standards.

Assessment of deep dynamic mechanical sensitivity in individuals with tension-type headache: The dynamic pressure algometry.

PubMed

Palacios-Ceña, M; Wang, K; Castaldo, M; Guerrero-Peral, Á; Caminero, A B; Fernández-de-Las-Peñas, C; Arendt-Nielsen, L

2017-09-01

To explore the validity of dynamic pressure algometry for evaluating deep dynamic mechanical sensitivity by assessing its association with headache features and widespread pressure sensitivity in tension-type headache (TTH). One hundred and eighty-eight subjects with TTH (70% women) participated. Deep dynamic sensitivity was assessed with a dynamic pressure algometry set (Aalborg University, Denmark © ) consisting of 11 different rollers including fixed levels from 500 g to 5300 g. Each roller was moved at a speed of 0.5 cm/s over a 60-mm horizontal line covering the temporalis muscle. Dynamic pain threshold (DPT-level of the first painful roller) was determined and pain intensity during DPT was rated on a numerical pain rate scale (NPRS, 0-10). Headache clinical features were collected on a headache diary. As gold standard, static pressure pain thresholds (PPT) were assessed over temporalis, C5/C6 joint, second metacarpal, and tibialis anterior muscle. Side-to-side consistency between DPT (r = 0.843, p < 0.001) and pain evoked (r = 0.712; p < 0.001) by dynamic algometer was observed. DPT was moderately associated with widespread PPTs (0.526 > r > 0.656, all p < 0.001). Furthermore, pain during DPT was negatively associated with widespread PPTs (-0.370 < r < -0.162, all p < 0.05). Dynamic pressure algometry was a valid tool for assessing deep dynamic mechanical sensitivity in TTH. DPT was associated with widespread pressure sensitivity independently of the frequency of headaches supporting that deep dynamic pressure sensitivity within the trigeminal area is consistent with widespread pressure sensitivity. Assessing deep static and dynamic somatic tissue pain sensitivity may provide new opportunities for differentiated diagnostics and possibly a new tool for assessing treatment effects. The current study found that dynamic pressure algometry in the temporalis muscle was associated with widespread pressure pain sensitivity in individuals with tension-type headache. The association was independent of the frequency of headaches. Assessing deep static and dynamic somatic tissue pain sensitivity may provide new opportunities for differentiated diagnostics and possibly a tool for assessing treatment effects. © 2017 European Pain Federation - EFIC®.

Ultra-Sensitive Detection of Plasmodium falciparum by Amplification of Multi-Copy Subtelomeric Targets

PubMed Central

Hofmann, Natalie; Mwingira, Felista; Shekalaghe, Seif; Robinson, Leanne J.; Mueller, Ivo; Felger, Ingrid

2015-01-01

Background Planning and evaluating malaria control strategies relies on accurate definition of parasite prevalence in the population. A large proportion of asymptomatic parasite infections can only be identified by surveillance with molecular methods, yet these infections also contribute to onward transmission to mosquitoes. The sensitivity of molecular detection by PCR is limited by the abundance of the target sequence in a DNA sample; thus, detection becomes imperfect at low densities. We aimed to increase PCR diagnostic sensitivity by targeting multi-copy genomic sequences for reliable detection of low-density infections, and investigated the impact of these PCR assays on community prevalence data. Methods and Findings Two quantitative PCR (qPCR) assays were developed for ultra-sensitive detection of Plasmodium falciparum, targeting the high-copy telomere-associated repetitive element 2 (TARE-2, ∼250 copies/genome) and the var gene acidic terminal sequence (varATS, 59 copies/genome). Our assays reached a limit of detection of 0.03 to 0.15 parasites/μl blood and were 10× more sensitive than standard 18S rRNA qPCR. In a population cross-sectional study in Tanzania, 295/498 samples tested positive using ultra-sensitive assays. Light microscopy missed 169 infections (57%). 18S rRNA qPCR failed to identify 48 infections (16%), of which 40% carried gametocytes detected by pfs25 quantitative reverse-transcription PCR. To judge the suitability of the TARE-2 and varATS assays for high-throughput screens, their performance was tested on sample pools. Both ultra-sensitive assays correctly detected all pools containing one low-density P. falciparum–positive sample, which went undetected by 18S rRNA qPCR, among nine negatives. TARE-2 and varATS qPCRs improve estimates of prevalence rates, yet other infections might still remain undetected when absent in the limited blood volume sampled. Conclusions Measured malaria prevalence in communities is largely determined by the sensitivity of the diagnostic tool used. Even when applying standard molecular diagnostics, prevalence in our study population was underestimated by 8% compared to the new assays. Our findings highlight the need for highly sensitive tools such as TARE-2 and varATS qPCR in community surveillance and for monitoring interventions to better describe malaria epidemiology and inform malaria elimination efforts. PMID:25734259

Enhancing malaria diagnosis through microfluidic cell enrichment and magnetic resonance relaxometry detection

NASA Astrophysics Data System (ADS)

Fook Kong, Tian; Ye, Weijian; Peng, Weng Kung; Wei Hou, Han; Marcos; Preiser, Peter Rainer; Nguyen, Nam-Trung; Han, Jongyoon

2015-06-01

Despite significant advancements over the years, there remains an urgent need for low cost diagnostic approaches that allow for rapid, reliable and sensitive detection of malaria parasites in clinical samples. Our previous work has shown that magnetic resonance relaxometry (MRR) is a potentially highly sensitive tool for malaria diagnosis. A key challenge for making MRR based malaria diagnostics suitable for clinical testing is the fact that MRR baseline fluctuation exists between individuals, making it difficult to detect low level parasitemia. To overcome this problem, it is important to establish the MRR baseline of each individual while having the ability to reliably determine any changes that are caused by the infection of malaria parasite. Here we show that an approach that combines the use of microfluidic cell enrichment with a saponin lysis before MRR detection can overcome these challenges and provide the basis for a highly sensitive and reliable diagnostic approach of malaria parasites. Importantly, as little as 0.0005% of ring stage parasites can be detected reliably, making this ideally suited for the detection of malaria parasites in peripheral blood obtained from patients. The approaches used here are envisaged to provide a new malaria diagnosis solution in the near future.

Riems influenza a typing array (RITA): An RT-qPCR-based low density array for subtyping avian and mammalian influenza a viruses.

PubMed

Hoffmann, Bernd; Hoffmann, Donata; Henritzi, Dinah; Beer, Martin; Harder, Timm C

2016-06-03

Rapid and sensitive diagnostic approaches are of the utmost importance for the detection of humans and animals infected by specific influenza virus subtype(s). Cascade-like diagnostics starting with the use of pan-influenza assays and subsequent subtyping devices are normally used. Here, we demonstrated a novel low density array combining 32 TaqMan(®) real-time RT-PCR systems in parallel for the specific detection of the haemagglutinin (HA) and neuraminidase (NA) subtypes of avian and porcine hosts. The sensitivity of the newly developed system was compared with that of the pan-influenza assay, and the specificity of all RT-qPCRs was examined using a broad panel of 404 different influenza A virus isolates representing 45 different subtypes. Furthermore, we analysed the performance of the RT-qPCR assays with diagnostic samples obtained from wild birds and swine. Due to the open format of the array, adaptations to detect newly emerging influenza A virus strains can easily be integrated. The RITA array represents a competitive, fast and sensitive subtyping tool that requires neither new machinery nor additional training of staff in a lab where RT-qPCR is already established.

Evaluation of PCR Approaches for Detection of Bartonella bacilliformis in Blood Samples.

PubMed

Gomes, Cláudia; Martinez-Puchol, Sandra; Pons, Maria J; Bazán, Jorge; Tinco, Carmen; del Valle, Juana; Ruiz, Joaquim

2016-03-01

The lack of an effective diagnostic tool for Carrion's disease leads to misdiagnosis, wrong treatments and perpetuation of asymptomatic carriers living in endemic areas. Conventional PCR approaches have been reported as a diagnostic technique. However, the detection limit of these techniques is not clear as well as if its usefulness in low bacteriemia cases. The aim of this study was to evaluate the detection limit of 3 PCR approaches. We determined the detection limit of 3 different PCR approaches: Bartonella-specific 16S rRNA, fla and its genes. We also evaluated the viability of dry blood spots to be used as a sample transport system. Our results show that 16S rRNA PCR is the approach with a lowest detection limit, 5 CFU/μL, and thus, the best diagnostic PCR tool studied. Dry blood spots diminish the sensitivity of the assay. From the tested PCRs, the 16S rRNA PCR-approach is the best to be used in the direct blood detection of acute cases of Carrion's disease. However its use in samples from dry blood spots results in easier management of transport samples in rural areas, a slight decrease in the sensitivity was observed. The usefulness to detect by PCR the presence of low-bacteriemic or asymptomatic carriers is doubtful, showing the need to search for new more sensible techniques.

Central Sensitization-Based Classification for Temporomandibular Disorders: A Pathogenetic Hypothesis

PubMed Central

Cattaneo, Ruggero; Marci, Maria Chiara; Pietropaoli, Davide; Ortu, Eleonora

2017-01-01

Dysregulation of Autonomic Nervous System (ANS) and central pain pathways in temporomandibular disorders (TMD) is a growing evidence. Authors include some forms of TMD among central sensitization syndromes (CSS), a group of pathologies characterized by central morphofunctional alterations. Central Sensitization Inventory (CSI) is useful for clinical diagnosis. Clinical examination and CSI cannot identify the central site(s) affected in these diseases. Ultralow frequency transcutaneous electrical nerve stimulation (ULFTENS) is extensively used in TMD and in dental clinical practice, because of its effects on descending pain modulation pathways. The Diagnostic Criteria for TMD (DC/TMD) are the most accurate tool for diagnosis and classification of TMD. However, it includes CSI to investigate central aspects of TMD. Preliminary data on sensory ULFTENS show it is a reliable tool for the study of central and autonomic pathways in TMD. An alternative classification based on the presence of Central Sensitization and on individual response to sensory ULFTENS is proposed. TMD may be classified into 4 groups: (a) TMD with Central Sensitization ULFTENS Responders; (b) TMD with Central Sensitization ULFTENS Nonresponders; (c) TMD without Central Sensitization ULFTENS Responders; (d) TMD without Central Sensitization ULFTENS Nonresponders. This pathogenic classification of TMD may help to differentiate therapy and aetiology. PMID:28932132

Is early detection of abused children possible?: a systematic review of the diagnostic accuracy of the identification of abused children

PubMed Central

2013-01-01

Background Early detection of abused children could help decrease mortality and morbidity related to this major public health problem. Several authors have proposed tools to screen for child maltreatment. The aim of this systematic review was to examine the evidence on accuracy of tools proposed to identify abused children before their death and assess if any were adapted to screening. Methods We searched in PUBMED, PsycINFO, SCOPUS, FRANCIS and PASCAL for studies estimating diagnostic accuracy of tools identifying neglect, or physical, psychological or sexual abuse of children, published in English or French from 1961 to April 2012. We extracted selected information about study design, patient populations, assessment methods, and the accuracy parameters. Study quality was assessed using QUADAS criteria. Results A total of 2 280 articles were identified. Thirteen studies were selected, of which seven dealt with physical abuse, four with sexual abuse, one with emotional abuse, and one with any abuse and physical neglect. Study quality was low, even when not considering the lack of gold standard for detection of abused children. In 11 studies, instruments identified abused children only when they had clinical symptoms. Sensitivity of tests varied between 0.26 (95% confidence interval [0.17-0.36]) and 0.97 [0.84-1], and specificity between 0.51 [0.39-0.63] and 1 [0.95-1]. The sensitivity was greater than 90% only for three tests: the absence of scalp swelling to identify children victims of inflicted head injury; a decision tool to identify physically-abused children among those hospitalized in a Pediatric Intensive Care Unit; and a parental interview integrating twelve child symptoms to identify sexually-abused children. When the sensitivity was high, the specificity was always smaller than 90%. Conclusions In 2012, there is low-quality evidence on the accuracy of instruments for identifying abused children. Identified tools were not adapted to screening because of low sensitivity and late identification of abused children when they have already serious consequences of maltreatment. Development of valid screening instruments is a pre-requisite before considering screening programs. PMID:24314318

Diagnostic and prognostic utility of an inexpensive rapid on site malaria diagnostic test (ParaHIT f) among ethnic tribal population in areas of high, low and no transmission in central India.

PubMed

Singh, Neeru; Mishra, A K; Shukla, M M; Chand, S K; Bharti, Praveen Kumar

2005-06-21

Malaria presents a diagnostic challenge in most tropical countries. Rapid detection of the malaria parasite and early treatment of infection still remain the most important goals of disease management. Therefore, performance characteristics of the new indigenous ParaHIT f test (Span diagnostic Ltd, Surat, India) was determined among ethnic tribal population in four districts of different transmission potential in central India to assess whether this rapid diagnostic test (RDT) could be widely applied as a diagnostic tool to control malaria. Beyond diagnosis, the logical utilization of RDTs is to monitor treatment outcome. A finger prick blood sample was collected from each clinically suspected case of malaria to prepare blood smear and for testing with the RDT after taking informed consent. The blood smears were read by an experienced technician blinded to the RDT results and clinical status of the subjects. The figures for specificity, sensitivity, accuracy and predictive values were calculated using microscopy as gold standard. The prevalence of malaria infection estimated by RDT in parallel with microscopy provide evidence of the type of high, low or no transmission in the study area. Analysis revealed (pooled data of all four epidemiological settings) that overall sensitivity, specificity and accuracy of the RDT were >90% in areas of different endemicity. While, RDT is useful to confirm the diagnosis of new symptomatic cases of suspected P. falciparum infection, the persistence of parasite antigen leading to false positives even after clearance of asexual parasitaemia has limited its utility as a prognostic tool. The study showed that the ParaHIT f test was easy to use, reliable and cheap. Thus this RDT is an appropriate test for the use in the field by paramedical staff when laboratory facilities are not available and thus likely to contribute greatly to an effective control of malaria in resource poor countries.

A Novel Malaria Pf/Pv Ab Rapid Diagnostic Test Using a Differential Diagnostic Marker Identified by Network Biology.

PubMed

Cho, Sung Jin; Lee, Jihoo; Lee, Hyun Jae; Jo, Hyun-Young; Sinniah, Mangalam; Kim, Hak-Yong; Chong, Chom-Kyu; Song, Hyun-Ok

2016-01-01

Rapid diagnostic tests (RDTs) can detect anti-malaria antibodies in human blood. As they can detect parasite infection at the low parasite density, they are useful in endemic areas where light infection and/or re-infection of parasites are common. Thus, malaria antibody tests can be used for screening bloods in blood banks to prevent transfusion-transmitted malaria (TTM), an emerging problem in malaria endemic areas. However, only a few malaria antibody tests are available in the microwell-based assay format and these are not suitable for field application. A novel malaria antibody (Ab)-based RDT using a differential diagnostic marker for falciparum and vivax malaria was developed as a suitable high-throughput assay that is sensitive and practical for blood screening. The marker, merozoite surface protein 1 (MSP1) was discovered by generation of a Plasmodium-specific network and the hierarchical organization of modularity in the network. Clinical evaluation revealed that the novel Malaria Pf/Pv Ab RDT shows improved sensitivity (98%) and specificity (99.7%) compared with the performance of a commercial kit, SD BioLine Malaria P.f/P.v (95.1% sensitivity and 99.1% specificity). The novel Malaria Pf/Pv Ab RDT has potential for use as a cost-effective blood-screening tool for malaria and in turn, reduces TTM risk in endemic areas.

A systematic review of diagnostic criteria for psoriasis in adults and children: evidence from studies with a primary aim to develop or validate diagnostic criteria.

PubMed

Burden-Teh, E; Phillips, R C; Thomas, K S; Ratib, S; Grindlay, D; Murphy, R

2017-11-06

The diagnosis of psoriasis in adults and children is made clinically, for both patient management and the selection of participants in research. Diagnostic criteria provide a structure for clinical assessment, which in turn helps standardize patient recruitment into clinical trials and case definitions in observational studies. The aim of this systematic review was to identify and critically appraise the published studies to date that had a primary research aim to develop or validate diagnostic criteria for psoriasis. A search of Ovid MEDLINE and Ovid Embase was conducted in October 2016. The primary objective was to record the sensitivity and specificity of diagnostic criteria for psoriasis. Secondary objectives included diagnostic recommendations, applicability to children and study characteristics. Diagnostic accuracy studies were critically appraised for risk of bias using the QUADAS-2 tool. Twenty-three studies met the inclusion criteria. None detailed clinical examination-based diagnostic criteria. The included criteria varied from genetic and molecular diagnostic models to skin imaging, histopathology, and questionnaire-based, computer-aided and traditional Chinese medicine criteria. High sensitivity and specificity (> 90%) were reported in many studies. However, the study authors often did not specify how the criteria would be used clinically or in research. This review identified studies with varying risk of bias, and due to each study developing separate criteria meta-analysis was not possible. Clinical examination-based diagnostic criteria are currently lacking for psoriasis. Future research could follow an international collaborative approach and employ study designs allowing high-quality diagnostic accuracy testing. Existing and newly developed criteria require validation. © 2017 British Association of Dermatologists.

Remote skin tissue diagnostics in vivo by fiber optic evanescent wave Fourier transform infrared (FEW-FTIR) spectroscopy

NASA Astrophysics Data System (ADS)

Afanasyeva, Natalia I.; Kolyakov, Sergei F.; Butvina, Leonid N.

1998-04-01

The new method of fiber-optical evanescent wave Fourier transform IR (FEW-FTIR) spectroscopy has been applied to the diagnostics of normal tissue, as well as precancerous and cancerous conditions. The FEW-FTIR technique is nondestructive and sensitive to changes of vibrational spectra in the IR region, without heating and damaging human and animal skin tissue. Therefore this method and technique is an ideal diagnostic tool for tumor and cancer characterization at an early stage of development on a molecular level. The application of fiber optic technology in the middle IR region is relatively inexpensive and can be adapted easily to any commercially available tabletop FTIR spectrometers. This method of diagnostics is fast, remote, and can be applied to many fields Noninvasive medical diagnostics of skin cancer and other skin diseases in vivo, ex vivo, and in vitro allow for the development convenient, remote clinical applications in dermatology and related fields. The spectral variations from normal to pathological skin tissue and environmental influence on skin have been measured and assigned in the regions of 850-4000 cm-1. The lipid structure changes are discussed. We are able to develop the spectral histopathology as a fast and informative tool of analysis.

INCLEN diagnostic tool for attention deficit hyperactivity disorder (INDT-ADHD): development and validation.

PubMed

Mukherjee, Sharmila; Aneja, Satinder; Russell, Paul S S; Gulati, Sheffali; Deshmukh, Vaishali; Sagar, Rajesh; Silberberg, Donald; Bhutani, Vinod K; Pinto, Jennifer M; Durkin, Maureen; Pandey, Ravindra M; Nair, M K C; Arora, Narendra K

2014-06-01

To develop and validate INCLEN Diagnostic Tool for Attention Deficit Hyperactivity Disorder (INDT-ADHD). Diagnostic test evaluation by cross sectional design. Tertiary care pediatric centers. 156 children aged 65-117 months. After randomization, INDT-ADHD and Connors 3 Parent Rating Scale (C3PS) were administered, followed by an expert evaluation by DSM-IV-TR diagnostic criteria. Psychometric evaluation of diagnostic accuracy, validity (construct, criterion and convergent) and internal consistency. INDT-ADHD had 18 items that quantified symptoms and impairment. Attention deficit hyperactivity disorder was identified in 57, 87 and 116 children by expert evaluation, INDT-ADHD and C3PS, respectively. Psychometric parameters of INDT-ADHD for differentiating attention deficit hyperactivity disorder and normal children were: sensitivity 87.7%, specificity 97.2%, positive predictive value 98.0% and negative predictive value 83.3%, whereas for differentiating from other neuro-developmental disorders were 87.7%, 42.9%, 58.1% and 79.4%, respectively. Internal consistency was 0.91. INDT-ADHD has a 4-factor structure explaining 60.4% of the variance. Convergent validity with Conner's Parents Rating Scale was moderate (r =0.73, P= 0.001). INDT-ADHD is suitable for diagnosing attention deficit hyperactivity disorder in Indian children between the ages of 6 to 9 years.

Detection of Grapevine Leafroll-associated virus 7 using real-time qRT-PCR and conventional RT-PCR

USDA-ARS?s Scientific Manuscript database

Nine isolates of Grapevine Leafroll-associated Virus 7 (GLRaV-7) from California have been sequenced to design more sensitive molecular diagnostic tools. These sequences were from the coat protein (CP) and the homologous heat shock protein (hHSP70) genes. Sequence identity among these isolates rang...

Nested PCR Assay for Eight Pathogens: A Rapid Tool for Diagnosis of Bacterial Meningitis.

PubMed

Bhagchandani, Sharda P; Kubade, Sushant; Nikhare, Priyanka P; Manke, Sonali; Chandak, Nitin H; Kabra, Dinesh; Baheti, Neeraj N; Agrawal, Vijay S; Sarda, Pankaj; Mahajan, Parikshit; Ganjre, Ashish; Purohit, Hemant J; Singh, Lokendra; Taori, Girdhar M; Daginawala, Hatim F; Kashyap, Rajpal S

2016-02-01

Bacterial meningitis is a dreadful infectious disease with a high mortality and morbidity if remained undiagnosed. Traditional diagnostic methods for bacterial meningitis pose a challenge in accurate identification of pathogen, making prognosis difficult. The present study is therefore aimed to design and evaluate a specific and sensitive nested 16S rDNA genus-based polymerase chain reaction (PCR) assay using clinical cerebrospinal fluid (CSF) for rapid diagnosis of eight pathogens causing the disease. The present work was dedicated to development of an in-house genus specific 16S rDNA nested PCR covering pathogens of eight genera responsible for causing bacterial meningitis using newly designed as well as literature based primers for respective genus. A total 150 suspected meningitis CSF obtained from the patients admitted to Central India Institute of Medical Sciences (CIIMS), India during the period from August 2011 to May 2014, were used to evaluate clinical sensitivity and clinical specificity of optimized PCR assays. The analytical sensitivity and specificity of our newly designed genus-specific 16S rDNA PCR were found to be ≥92%. With such a high sensitivity and specificity, our in-house nested PCR was able to give 100% sensitivity in clinically confirmed positive cases and 100% specificity in clinically confirmed negative cases indicating its applicability in clinical diagnosis. Our in-house nested PCR system therefore can diagnose the accurate pathogen causing bacterial meningitis and therefore be useful in selecting a specific treatment line to minimize morbidity. Results are obtained within 24 h and high sensitivity makes this nested PCR assay a rapid and accurate diagnostic tool compared to traditional culture-based methods.

Assessment of African Swine Fever Diagnostic Techniques as a Response to the Epidemic Outbreaks in Eastern European Union Countries: How To Improve Surveillance and Control Programs

PubMed Central

Nieto, R.; Soler, A.; Pelayo, V.; Fernández-Pinero, J.; Markowska-Daniel, I.; Pridotkas, G.; Nurmoja, I.; Granta, R.; Simón, A.; Pérez, C.; Martín, E.; Fernández-Pacheco, P.; Arias, M.

2015-01-01

This study represents a complete comparative analysis of the most widely used African swine fever (ASF) diagnostic techniques in the European Union (EU) using field and experimental samples from animals infected with genotype II ASF virus (ASFV) isolates circulating in Europe. To detect ASFV, three different PCRs were evaluated in parallel using 785 field and experimental samples. The results showed almost perfect agreement between the Universal ProbeLibrary (UPL-PCR) and the real-time (κ = 0.94 [95% confidence interval {CI}, 0.91 to 0.97]) and conventional (κ = 0.88 [95% CI, 0.83 to 0.92]) World Organisation for Animal Health (OIE)-prescribed PCRs. The UPL-PCR had greater diagnostic sensitivity for detecting survivors and allows earlier detection of the disease. Compared to the commercial antigen enzyme-linked immunosorbent assay (ELISA), good-to-moderate agreement (κ = 0.67 [95% CI, 0.58 to 0.76]) was obtained, with a sensitivity of 77.2% in the commercial test. For ASF antibody detection, five serological methods were tested, including three commercial ELISAs, the OIE-ELISA, and the confirmatory immunoperoxidase test (IPT). Greater sensitivity was obtained with the IPT than with the ELISAs, since the IPT was able to detect ASF antibodies at an earlier point in the serological response, when few antibodies are present. The analysis of the exudate tissues from dead wild boars showed that IPT might be a useful serological tool for determining whether or not animals had been exposed to virus infection, regardless of whether antibodies were present. In conclusion, the UPL-PCR in combination with the IPT was the most trustworthy method for detecting ASF during the epidemic outbreaks affecting EU countries in 2014. The use of the most appropriate diagnostic tools is critical when implementing effective control programs. PMID:26041901

Assessment of African Swine Fever Diagnostic Techniques as a Response to the Epidemic Outbreaks in Eastern European Union Countries: How To Improve Surveillance and Control Programs.

PubMed

Gallardo, C; Nieto, R; Soler, A; Pelayo, V; Fernández-Pinero, J; Markowska-Daniel, I; Pridotkas, G; Nurmoja, I; Granta, R; Simón, A; Pérez, C; Martín, E; Fernández-Pacheco, P; Arias, M

2015-08-01

This study represents a complete comparative analysis of the most widely used African swine fever (ASF) diagnostic techniques in the European Union (EU) using field and experimental samples from animals infected with genotype II ASF virus (ASFV) isolates circulating in Europe. To detect ASFV, three different PCRs were evaluated in parallel using 785 field and experimental samples. The results showed almost perfect agreement between the Universal ProbeLibrary (UPL-PCR) and the real-time (κ = 0.94 [95% confidence interval {CI}, 0.91 to 0.97]) and conventional (κ = 0.88 [95% CI, 0.83 to 0.92]) World Organisation for Animal Health (OIE)-prescribed PCRs. The UPL-PCR had greater diagnostic sensitivity for detecting survivors and allows earlier detection of the disease. Compared to the commercial antigen enzyme-linked immunosorbent assay (ELISA), good-to-moderate agreement (κ = 0.67 [95% CI, 0.58 to 0.76]) was obtained, with a sensitivity of 77.2% in the commercial test. For ASF antibody detection, five serological methods were tested, including three commercial ELISAs, the OIE-ELISA, and the confirmatory immunoperoxidase test (IPT). Greater sensitivity was obtained with the IPT than with the ELISAs, since the IPT was able to detect ASF antibodies at an earlier point in the serological response, when few antibodies are present. The analysis of the exudate tissues from dead wild boars showed that IPT might be a useful serological tool for determining whether or not animals had been exposed to virus infection, regardless of whether antibodies were present. In conclusion, the UPL-PCR in combination with the IPT was the most trustworthy method for detecting ASF during the epidemic outbreaks affecting EU countries in 2014. The use of the most appropriate diagnostic tools is critical when implementing effective control programs. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

APRI test and hyaluronic acid as non-invasive diagnostic tools for post HCV liver fibrosis: Systematic review and meta-analysis.

PubMed

El Serafy, Magdy Amin; Kassem, Abdel Meguid; Omar, Heba; Mahfouz, Mohammad Shaaban; El Said El Raziky, Maissa

2017-06-01

Hepatitis C virus (HCV) accounts for a sizable proportion of chronic liver disease cases and represents the most common indication for liver transplantation. Precise diagnosis of hepatic fibrosis stage is considered a funnel-neck in proper management and follow-up of HCV-infected patients. Given the possible complications of liver biopsy, a non-invasive method for assessing hepatic fibrosis is needed. This study aimed to evaluate the diagnostic accuracy of APRI and hyaluronic acid as non-invasive diagnostic assessment tools for post HCV liver fibrosis. Systematic literature searching identified studies performed on Egyptian territory to evaluate APRI and hyaluronic acid as non-invasive tests of fibrosis and using liver biopsy as the reference standard. Meta-analysis was performed for areas with an adequate number of publications. Validation of meta- analysis on APRI was done on a subset of 150 treatment-naïve post-hepatitis C patients. Both APRI and hyaluronic acid have superior predictive power for hepatic cirrhosis (F4) than for significant fibrosis (F2-F3). The pooled estimate for sensitivities and specificities of APRI and hyaluronic acid to diagnose F4 were (84% and 82%) and (83% and 89%) respectively. In the subgroup of treatment naïve post-hepatitis C patients, APRI had higher diagnostic performance to diagnose liver cirrhosis with 93.8% sensitivity and 72.4% specificity (AUC; 0.908, 95%CI; 0.851-0.965, p-value; <0.001) compared to its accuracy to diagnose significant hepatic fibrosis with 65.1% sensitivity and 77.8% (AUC; 0.685, 95% CI; 0.59-0.78, p-value; 0.001). APRI score and hyaluronic acid levels are simple and reliable non-invasive markers to detect advanced fibrosis among post-hepatitis C patients. Copyright © 2017 Pan-Arab Association of Gastroenterology. Published by Elsevier B.V. All rights reserved.

The Rapid-Heat LAMPellet Method: A Potential Diagnostic Method for Human Urogenital Schistosomiasis

PubMed Central

Carranza-Rodríguez, Cristina; Pérez-Arellano, José Luis; Vicente, Belén; López-Abán, Julio; Muro, Antonio

2015-01-01

Background Urogenital schistosomiasis due to Schistosoma haematobium is a serious underestimated public health problem affecting 112 million people - particularly in sub-Saharan Africa. Microscopic examination of urine samples to detect parasite eggs still remains as definitive diagnosis. This work was focussed on developing a novel loop-mediated isothermal amplification (LAMP) assay for detection of S. haematobium DNA in human urine samples as a high-throughput, simple, accurate and affordable diagnostic tool to use in diagnosis of urogenital schistosomiasis. Methodology/Principal Findings A LAMP assay targeting a species specific sequence of S. haematobium ribosomal intergenic spacer was designed. The effectiveness of our LAMP was assessed in a number of patients´ urine samples with microscopy confirmed S. haematobium infection. For potentially large-scale application in field conditions, different DNA extraction methods, including a commercial kit, a modified NaOH extraction method and a rapid heating method were tested using small volumes of urine fractions (whole urine, supernatants and pellets). The heating of pellets from clinical samples was the most efficient method to obtain good-quality DNA detectable by LAMP. The detection limit of our LAMP was 1 fg/µL of S. haematobium DNA in urine samples. When testing all patients´ urine samples included in our study, diagnostic parameters for sensitivity and specificity were calculated for LAMP assay, 100% sensitivity (95% CI: 81.32%-100%) and 86.67% specificity (95% CI: 75.40%-94.05%), and also for microscopy detection of eggs in urine samples, 69.23% sensitivity (95% CI: 48.21% -85.63%) and 100% specificity (95% CI: 93.08%-100%). Conclusions/Significance We have developed and evaluated, for the first time, a LAMP assay for detection of S. haematobium DNA in heated pellets from patients´ urine samples using no complicated requirement procedure for DNA extraction. The procedure has been named the Rapid-Heat LAMPellet method and has the potential to be developed further as a field diagnostic tool for use in urogenital schistosomiasis-endemic areas. PMID:26230990

DNA-mounted self-assembly: new approaches for genomic analysis and SNP detection.

PubMed

Bichenkova, Elena V; Lang, Zhaolei; Yu, Xuan; Rogert, Candelaria; Douglas, Kenneth T

2011-01-01

This article presents an overview of new emerging approaches for nucleic acid detection via hybridization techniques that can potentially be applied to genomic analysis and SNP identification in clinical diagnostics. Despite the availability of a diverse variety of SNP genotyping technologies on the diagnostic market, none has truly succeeded in dominating its competitors thus far. Having been designed for specific diagnostic purposes or clinical applications, each of the existing bio-assay systems (briefly outlined here) is usually limited to a relatively narrow aspect or format of nucleic acid detection, and thus cannot entirely satisfy all the varieties of commercial requirements and clinical demands. This drives the diagnostic sector to pursue novel, cost-effective approaches to ensure rapid and reliable identification of pathogenic or hereditary human diseases. Hence, the purpose of this review is to highlight some new strategic directions in DNA detection technologies in order to inspire development of novel molecular diagnostic tools and bio-assay systems with superior reliability, reproducibility, robustness, accuracy and sensitivity at lower assay cost. One approach to improving the sensitivity of an assay to confidently discriminate between single point mutations is based on the use of target assembled, split-probe systems, which constitutes the main focus of this review. Copyright © 2010 Elsevier B.V. All rights reserved.

Clinical application of optical coherence tomography in combination with functional diagnostics: advantages and limitations for diagnosis and assessment of therapy outcome in central serous chorioretinopathy.

PubMed

Schliesser, Joshua A; Gallimore, Gary; Kunjukunju, Nancy; Sabates, Nelson R; Koulen, Peter; Sabates, Felix N

2014-01-01

While identifying functional and structural parameters of the retina in central serous chorioretinopathy (CSCR) patients, this study investigated how an optical coherence tomography (OCT)-based diagnosis can be significantly supplemented with functional diagnostic tools and to what degree the determination of disease severity and therapy outcome can benefit from diagnostics complementary to OCT. CSCR patients were evaluated prospectively with microperimetry (MP) and spectral domain optical coherence tomography (SD-OCT) to determine retinal sensitivity function and retinal thickness as outcome measures along with measures of visual acuity (VA). Patients received clinical care that involved focal laser photocoagulation or pharmacotherapy targeting inflammation and neovascularization. Correlation of clinical parameters with a focus on functional parameters, VA, and mean retinal sensitivity, as well as on the structural parameter mean retinal thickness, showed that functional measures were similar in diagnostic power. A moderate correlation was found between OCT data and the standard functional assessment of VA; however, a strong correlation between OCT and MP data showed that diagnostic measures cannot always be used interchangeably, but that complementary use is of higher clinical value. The study indicates that integrating SD-OCT with MP provides a more complete diagnosis with high clinical relevance for complex, difficult to quantify diseases such as CSCR.

Is the Atopy Patch Test Reliable in the Evaluation of Food Allergy-Related Atopic Dermatitis?

PubMed

Mansouri, Mahboubeh; Rafiee, Elham; Darougar, Sepideh; Mesdaghi, Mehrnaz; Chavoshzadeh, Zahra

2018-01-01

Aeroallergens and food allergens are found to be relevant in atopic dermatitis. The atopy patch test (APT) can help to detect food allergies in children with atopic dermatitis. This study evaluates if the APT is a valuable tool in the diagnostic workup of children with food allergy-related atopic dermatitis. 42 children between 6 months and 12 years of age were selected at the Mofid Children Hospital. Atopic dermatitis was diagnosed, and the severity of the disease was determined. At the test visit, the patients underwent a skin prick test (SPT), APT, and serum IgE level measurement for cow's milk, egg yolk, egg white, wheat, and soy. We found a sensitivity of 91.7%, a specificity of 72.7%, a positive predictive value (PPV) of 88%, a negative predictive value (NPV) of 80%, and an accuracy of 85.7% for APT performed for cow's milk. APT performed for egg yolk had a sensitivity and a NPV of 100%, while the same parameters obtained with egg white were 84.2 and 75%, respectively. The sensitivity, specificity, and NPV of the APT for wheat were 100, 75, and 100%, respectively. The sensitivity, PPV, and NPV of the APT for soy were 87.5, 70, and 87.5%, respectively. Our data demonstrate that the APT is a reliable diagnostic tool to evaluate suspected food allergy-related skin symptoms in childhood and infancy. © 2018 S. Karger AG, Basel.

Quality and reporting of diagnostic accuracy studies in TB, HIV and malaria: evaluation using QUADAS and STARD standards.

PubMed

Fontela, Patricia Scolari; Pant Pai, Nitika; Schiller, Ian; Dendukuri, Nandini; Ramsay, Andrew; Pai, Madhukar

2009-11-13

Poor methodological quality and reporting are known concerns with diagnostic accuracy studies. In 2003, the QUADAS tool and the STARD standards were published for evaluating the quality and improving the reporting of diagnostic studies, respectively. However, it is unclear whether these tools have been applied to diagnostic studies of infectious diseases. We performed a systematic review on the methodological and reporting quality of diagnostic studies in TB, malaria and HIV. We identified diagnostic accuracy studies of commercial tests for TB, malaria and HIV through a systematic search of the literature using PubMed and EMBASE (2004-2006). Original studies that reported sensitivity and specificity data were included. Two reviewers independently extracted data on study characteristics and diagnostic accuracy, and used QUADAS and STARD to evaluate the quality of methods and reporting, respectively. Ninety (38%) of 238 articles met inclusion criteria. All studies had design deficiencies. Study quality indicators that were met in less than 25% of the studies included adequate description of withdrawals (6%) and reference test execution (10%), absence of index test review bias (19%) and reference test review bias (24%), and report of uninterpretable results (22%). In terms of quality of reporting, 9 STARD indicators were reported in less than 25% of the studies: methods for calculation and estimates of reproducibility (0%), adverse effects of the diagnostic tests (1%), estimates of diagnostic accuracy between subgroups (10%), distribution of severity of disease/other diagnoses (11%), number of eligible patients who did not participate in the study (14%), blinding of the test readers (16%), and description of the team executing the test and management of indeterminate/outlier results (both 17%). The use of STARD was not explicitly mentioned in any study. Only 22% of 46 journals that published the studies included in this review required authors to use STARD. Recently published diagnostic accuracy studies on commercial tests for TB, malaria and HIV have moderate to low quality and are poorly reported. The more frequent use of tools such as QUADAS and STARD may be necessary to improve the methodological and reporting quality of future diagnostic accuracy studies in infectious diseases.

Quality and Reporting of Diagnostic Accuracy Studies in TB, HIV and Malaria: Evaluation Using QUADAS and STARD Standards

PubMed Central

Fontela, Patricia Scolari; Pant Pai, Nitika; Schiller, Ian; Dendukuri, Nandini; Ramsay, Andrew; Pai, Madhukar

2009-01-01

Background Poor methodological quality and reporting are known concerns with diagnostic accuracy studies. In 2003, the QUADAS tool and the STARD standards were published for evaluating the quality and improving the reporting of diagnostic studies, respectively. However, it is unclear whether these tools have been applied to diagnostic studies of infectious diseases. We performed a systematic review on the methodological and reporting quality of diagnostic studies in TB, malaria and HIV. Methods We identified diagnostic accuracy studies of commercial tests for TB, malaria and HIV through a systematic search of the literature using PubMed and EMBASE (2004–2006). Original studies that reported sensitivity and specificity data were included. Two reviewers independently extracted data on study characteristics and diagnostic accuracy, and used QUADAS and STARD to evaluate the quality of methods and reporting, respectively. Findings Ninety (38%) of 238 articles met inclusion criteria. All studies had design deficiencies. Study quality indicators that were met in less than 25% of the studies included adequate description of withdrawals (6%) and reference test execution (10%), absence of index test review bias (19%) and reference test review bias (24%), and report of uninterpretable results (22%). In terms of quality of reporting, 9 STARD indicators were reported in less than 25% of the studies: methods for calculation and estimates of reproducibility (0%), adverse effects of the diagnostic tests (1%), estimates of diagnostic accuracy between subgroups (10%), distribution of severity of disease/other diagnoses (11%), number of eligible patients who did not participate in the study (14%), blinding of the test readers (16%), and description of the team executing the test and management of indeterminate/outlier results (both 17%). The use of STARD was not explicitly mentioned in any study. Only 22% of 46 journals that published the studies included in this review required authors to use STARD. Conclusion Recently published diagnostic accuracy studies on commercial tests for TB, malaria and HIV have moderate to low quality and are poorly reported. The more frequent use of tools such as QUADAS and STARD may be necessary to improve the methodological and reporting quality of future diagnostic accuracy studies in infectious diseases. PMID:19915664

Dermoscopy, Digital Dermoscopy and Other Diagnostic Tools in the Early Detection of Melanoma and Follow-up of High-risk Skin Cancer Patients.

PubMed

Thomas, Luc; Puig, Susana

2017-07-05

Early detection is a key strategy for reducing the mortality and economic burden associated with melanoma. Dermoscopy is a non-invasive and cost-effective tool for melanoma diagnosis, which has been shown to be a reliable and sensitive method for detecting early-stage skin cancer and reducing the number of unnecessary excisions. Patients at high risk of developing melanoma require long-term surveillance. Use of digital dermoscopy follow-up of these patients has led to improved outcomes. Combined follow-up programmes using total-body photography and digital dermoscopy have led to further improvements in early diagnosis and diagnostic accuracy. Dermoscopy is now widely used by dermatologists, but the public health impact of this tool is yet to be evaluated. Despite the clear advantages of dermoscopy and digital follow-up meth-ods, dermoscopy training and access to digital dermoscopy among dermatologists and general practitioners needs to be improved.

Development of Molecular Methods to Detect Macrophomina phaseolina from Strawberry Plants and Soil.

PubMed

Burkhardt, Alyssa; Ramon, Marina L; Smith, Brett; Koike, Steven T; Martin, Frank N

2018-06-05

Macrophomina phaseolina is a broad-host range fungus that shows some degree of host preference on strawberry, and causes symptoms including crown rot and root rot. Recently, this pathogen has impacted strawberry production as fumigation practices have changed, leaving many growers in California and around the world in need of accurate, rapid diagnostic tools for M. phaseolina in soil and infected plants. This study uses next-generation sequencing and comparative genomics to identify a locus that is unique to isolates within a main genotype shared by a majority of isolates that infect strawberry. This locus was used to develop a quantitative single-tube nested TaqMan qPCR assay which is able to quantify as little as 2-3 microsclerotia/g of soil with 100% genotype specificity. An isothermal assay using recombinase polymerase amplification (RPA) was developed from the same locus and has been validated on over 200 infected strawberry plants with a diagnostic sensitivity of 93% and a diagnostic specificity of 99%, respectively. Together, this work demonstrates the value of using new approaches to identify loci for detection and provides valuable diagnostic tools that can be used to monitor soil and strawberry plant samples for M. phaseolina.

The complementary role of music therapy in the detection of awareness in disorders of consciousness: an audit of concurrent SMART and MATADOC assessments.

PubMed

O'Kelly, Julian; Magee, Wendy L

2013-01-01

In the behavioural assessment of disorders of consciousness (DOC), best practice is for several different assessment tools to be used to encourage a variety of different responses indicative of awareness. Anecdotal evidence suggests a range of musical stimuli may be particularly effective in eliciting responses to guide the assessment process, although comparative data regarding behavioural domains is lacking. This study examined 42 concurrent records of patients assessed using the Sensory Modality Assessment and Rehabilitation Technique (SMART), and the Music Therapy Assessment Tool for Awareness in Disorders of Consciousness (MATADOC) to explore the relationship between diagnosis and behavioural characteristics of the cohort. Whilst the two tools produced a high level of agreement in diagnostic outcome (Spearman Rho .80), divergent diagnosis and weaker correlations between behavioural response items highlight contrasting sensitivities of the tools. Whilst MATADOC has higher sensitivity within auditory and visual domains relative to SMART, SMART has higher sensitivity in the motor domain. The significant contribution of musical response items in MATADOC, and the tactile response item in SMART, indicates both tools provide unique behavioural data predictive of awareness. Multidisciplinary assessment using SMART and MATADOC provides complementary data contributing to a fuller understanding of a patient's level of awareness.

Early, Accurate Diagnosis and Early Intervention in Cerebral Palsy: Advances in Diagnosis and Treatment.

PubMed

Novak, Iona; Morgan, Cathy; Adde, Lars; Blackman, James; Boyd, Roslyn N; Brunstrom-Hernandez, Janice; Cioni, Giovanni; Damiano, Diane; Darrah, Johanna; Eliasson, Ann-Christin; de Vries, Linda S; Einspieler, Christa; Fahey, Michael; Fehlings, Darcy; Ferriero, Donna M; Fetters, Linda; Fiori, Simona; Forssberg, Hans; Gordon, Andrew M; Greaves, Susan; Guzzetta, Andrea; Hadders-Algra, Mijna; Harbourne, Regina; Kakooza-Mwesige, Angelina; Karlsson, Petra; Krumlinde-Sundholm, Lena; Latal, Beatrice; Loughran-Fowlds, Alison; Maitre, Nathalie; McIntyre, Sarah; Noritz, Garey; Pennington, Lindsay; Romeo, Domenico M; Shepherd, Roberta; Spittle, Alicia J; Thornton, Marelle; Valentine, Jane; Walker, Karen; White, Robert; Badawi, Nadia

2017-09-01

Cerebral palsy describes the most common physical disability in childhood and occurs in 1 in 500 live births. Historically, the diagnosis has been made between age 12 and 24 months but now can be made before 6 months' corrected age. To systematically review best available evidence for early, accurate diagnosis of cerebral palsy and to summarize best available evidence about cerebral palsy-specific early intervention that should follow early diagnosis to optimize neuroplasticity and function. This study systematically searched the literature about early diagnosis of cerebral palsy in MEDLINE (1956-2016), EMBASE (1980-2016), CINAHL (1983-2016), and the Cochrane Library (1988-2016) and by hand searching. Search terms included cerebral palsy, diagnosis, detection, prediction, identification, predictive validity, accuracy, sensitivity, and specificity. The study included systematic reviews with or without meta-analyses, criteria of diagnostic accuracy, and evidence-based clinical guidelines. Findings are reported according to the PRISMA statement, and recommendations are reported according to the Appraisal of Guidelines, Research and Evaluation (AGREE) II instrument. Six systematic reviews and 2 evidence-based clinical guidelines met inclusion criteria. All included articles had high methodological Quality Assessment of Diagnostic Accuracy Studies (QUADAS) ratings. In infants, clinical signs and symptoms of cerebral palsy emerge and evolve before age 2 years; therefore, a combination of standardized tools should be used to predict risk in conjunction with clinical history. Before 5 months' corrected age, the most predictive tools for detecting risk are term-age magnetic resonance imaging (86%-89% sensitivity), the Prechtl Qualitative Assessment of General Movements (98% sensitivity), and the Hammersmith Infant Neurological Examination (90% sensitivity). After 5 months' corrected age, the most predictive tools for detecting risk are magnetic resonance imaging (86%-89% sensitivity) (where safe and feasible), the Hammersmith Infant Neurological Examination (90% sensitivity), and the Developmental Assessment of Young Children (83% C index). Topography and severity of cerebral palsy are more difficult to ascertain in infancy, and magnetic resonance imaging and the Hammersmith Infant Neurological Examination may be helpful in assisting clinical decisions. In high-income countries, 2 in 3 individuals with cerebral palsy will walk, 3 in 4 will talk, and 1 in 2 will have normal intelligence. Early diagnosis begins with a medical history and involves using neuroimaging, standardized neurological, and standardized motor assessments that indicate congruent abnormal findings indicative of cerebral palsy. Clinicians should understand the importance of prompt referral to diagnostic-specific early intervention to optimize infant motor and cognitive plasticity, prevent secondary complications, and enhance caregiver well-being.

The comparative accuracy of rapid diagnostic test with microscopy to diagnose malaria in subdistrict lima puluh batubara regency North Sumatera province

NASA Astrophysics Data System (ADS)

Rezeki, S.; Pasaribu, A. P.

2018-03-01

Indonesia is the country where malaria is still the most common population problem. The high rate of mortality and morbidity occurred due to delays in diagnosis whichis strongly influenced by the availability of diagnostic tools and personnel with required laboratory skill. This diagnostic study aims to compare the accuracy of a Rapid Diagnostic Test (RDT) without skill requirement, to agold standard microscopic method for malaria diagnosis. The study was conducted in Subdistrict Lima Puluh North Sumatera Province from December 2015 to January 2016. The subject was taken cross-sectionally from a population with characteristics typically found in malaria patients in Subdistrict Lima Puluh. The result showed a sensitivity of 100% and a specificity of 72.4% with a positive predictive value of 89.9% and a negative predictive value of 100%; the negative likelihood ratio is 0 and the positive likelihood ratio of 27.6 for Parascreen. This research indicates that Parascreen had a high sensitivity and specificity and may be consideredas an alternative for the diagnosis of malaria in Subdistrict Lima Puluh North Sumatera Province especially in areas where no skilled microscopist is available.

Parasites under the Spotlight: Applications of Vibrational Spectroscopy to Malaria Research.

PubMed

Perez-Guaita, David; Marzec, Katarzyna M; Hudson, Andrew; Evans, Corey; Chernenko, Tatyana; Matthäus, Christian; Miljkovic, Milos; Diem, Max; Heraud, Philip; Richards, Jack S; Andrew, Dean; Anderson, David A; Doerig, Christian; Garcia-Bustos, Jose; McNaughton, Don; Wood, Bayden R

2018-04-20

New technologies to diagnose malaria at high sensitivity and specificity are urgently needed in the developing world where the disease continues to pose a huge burden on society. Infrared and Raman spectroscopy-based diagnostic methods have a number of advantages compared with other diagnostic tests currently on the market. These include high sensitivity and specificity for detecting low levels of parasitemia along with ease of use and portability. Here, we review the application of vibrational spectroscopic techniques for monitoring and detecting malaria infection. We discuss the role of vibrational (infrared and Raman) spectroscopy in understanding the processes of parasite biology and its application to the study of interactions with antimalarial drugs. The distinct molecular phenotype that characterizes malaria infection and the high sensitivity enabling detection of low parasite densities provides a genuine opportunity for vibrational spectroscopy to become a front-line tool in the elimination of this deadly disease and provide molecular insights into the chemistry of this unique organism.

Rapid and visual detection of Leptospira in urine by LigB-LAMP assay with pre-addition of dye.

PubMed

Ali, Syed Atif; Kaur, Gurpreet; Boby, Nongthombam; Sabarinath, T; Solanki, Khushal; Pal, Dheeraj; Chaudhuri, Pallab

2017-12-01

Leptospirosis is considered to be the most widespread zoonotic disease caused by pathogenic species of Leptospira. The present study reports a novel set of primers targeting LigB gene for visual detection of pathogenic Leptospira in urine samples through Loop-mediated isothermal amplification (LAMP). The results were recorded by using Hydroxyl napthol blue (HNB), SYBR GREEN I and calcein. Analytical sensitivity of LAMP was as few as 10 leptospiral organisms in spiked urine samples from cattle and dog. LigB gene based LAMP, termed as LigB-LAMP, was found 10 times more sensitive than conventional PCR. The diagnostic specificity of LAMP was 100% when compared to SYBR green qPCR for detection of Leptospira in urine samples. Though qPCR was found more sensitive, the rapidity and simplicity in setting LAMP test followed by visual detection of Leptospira infection in clinical samples makes LigB-LAMP an alternative and favourable diagnostic tool in resource poor setting. Copyright © 2017 Elsevier Ltd. All rights reserved.

Diagnostic accuracy of the 14C-urea breath test in Helicobacter pylori infections: a meta-analysis.

PubMed

Zhou, Qiaohui; Li, Ling; Ai, Yaowei; Pan, Zhihong; Guo, Mingwen; Han, Jingbo

2017-01-01

To summarize and appraise the available literature regarding the use of the 14 C-urea breath test in the diagnosis of Helicobacter pylori infections in adult patients with dyspepsia and to calculate pooled diagnostic accuracy measures. We systematically searched the PubMed, EMBASE, Cochrane Library, Chinese Journals Full-text (CNKI) and CBMDisc databases to identify published data regarding the sensitivity, specificity, and other measures of diagnostic accuracy of the 14 C-urea breath test in the diagnosis of Helicobacter pylori infections in adult patients with dyspeptic symptoms. Risk of bias was assessed using the QUADAS (Quality Assessment of Diagnostic Accuracy Studies)-2 tool. Statistical analyses were performed using Meta-Disc 1.4 software and STATA. Eighteen studies met the inclusion criteria. Pooled results indicated that the  14 C-urea breath test showed a diagnostic sensitivity of 0.96 (95% CI 0.95 to 0.96) and specificity of 0.93 (95% CI 0.91 to 0.94). The positive like ratio (PLR) was 12.27 (95% CI 8.17 to 18.44), the negative like ratio (NLR) was 0.05 (95% CI 0.04 to 0.07), and the area under the curve was 0.985. The DOR was 294.95 (95% CI 178.37 to 487.70). The 14 C-urea breath test showed sufficient sensitivity and specificity for diagnosing Helicobacter pylori infection, but unexplained heterogeneity after meta-regression and several subgroup analyses remained. The UBT has high accuracy for diagnosing H. pylori infections in adult patients with dyspepsia. However, the reliability of these diagnostic meta-analytic estimates is limited by significant heterogeneity due to unknown factors.

Integrating Oil Debris and Vibration Measurements for Intelligent Machine Health Monitoring. Degree awarded by Toledo Univ., May 2002

NASA Technical Reports Server (NTRS)

Dempsey, Paula J.

2003-01-01

A diagnostic tool for detecting damage to gears was developed. Two different measurement technologies, oil debris analysis and vibration were integrated into a health monitoring system for detecting surface fatigue pitting damage on gears. This integrated system showed improved detection and decision-making capabilities as compared to using individual measurement technologies. This diagnostic tool was developed and evaluated experimentally by collecting vibration and oil debris data from fatigue tests performed in the NASA Glenn Spur Gear Fatigue Rig. An oil debris sensor and the two vibration algorithms were adapted as the diagnostic tools. An inductance type oil debris sensor was selected for the oil analysis measurement technology. Gear damage data for this type of sensor was limited to data collected in the NASA Glenn test rigs. For this reason, this analysis included development of a parameter for detecting gear pitting damage using this type of sensor. The vibration data was used to calculate two previously available gear vibration diagnostic algorithms. The two vibration algorithms were selected based on their maturity and published success in detecting damage to gears. Oil debris and vibration features were then developed using fuzzy logic analysis techniques, then input into a multi sensor data fusion process. Results show combining the vibration and oil debris measurement technologies improves the detection of pitting damage on spur gears. As a result of this research, this new diagnostic tool has significantly improved detection of gear damage in the NASA Glenn Spur Gear Fatigue Rigs. This research also resulted in several other findings that will improve the development of future health monitoring systems. Oil debris analysis was found to be more reliable than vibration analysis for detecting pitting fatigue failure of gears and is capable of indicating damage progression. Also, some vibration algorithms are as sensitive to operational effects as they are to damage. Another finding was that clear threshold limits must be established for diagnostic tools. Based on additional experimental data obtained from the NASA Glenn Spiral Bevel Gear Fatigue Rig, the methodology developed in this study can be successfully implemented on other geared systems.

[Sensitivity and specificity between the Composite International Diagnostic Interview Version 3.0 (World Mental Health, CIDI) and the Standardised Clinical Evaluation version I (SCID-I) in a mental health survey of the city of Medellin, 2012].

PubMed

Montoya Gonzalez, Laura Elisa; Restrepo Bernal, Diana Patricia; Mejía-Montoya, Roberto; Bareño-Silva, José; Sierra-Hincapié, Gloria; Torres de Galvis, Yolanda; Marulanda-Restrepo, Daniel; Gómez-Sierra, Natalia; Gaviria-Arbeláez, Silvia

2016-01-01

In order to address the mental health problems of the Colombian population it is necessary to have diagnostic tools (local and international) that are valid, easy to apply, and comparable. To compare the sensitivity and specificity between the CIDI 3.0 and the SCID-I for major depressive disorder, bipolar I and II disorder, and substance dependence disorder. Cross-sectional study comparing the life prevalence of three mental disorders in 100 subjects using the CIDI 3.0 and the SCID-I. The study was approved by the Institutional Ethics Committee. The two diagnostic interviews were performed that measured by sensitivity, specificity, positive predictive value and negative predictive value with confidence intervals of 95%. The SPSS version 21.0 software was used for data analysis. The median age was 43.5 years, with an interquartile interval of 30 years. The highest sensitivity (Se) and specificity (Sp) was observed for drug dependence diagnosis - with 80%, (95%CI, 34.94-100), and 98.46 (95%CI, 94.7-100), respectively. SCID-I and CIDI 3.0 showed different levels of sensitivity and specificity for the three disorders studied with: high for substance dependence disorder, moderate for bipolar disorder I and II, and low for major depressive disorder. Copyright © 2015 Asociación Colombiana de Psiquiatría. All rights reserved.

The future of targeted peptidomics.

PubMed

Findeisen, Peter

2013-12-01

Targeted MS is becoming increasingly important for sensitive and specific quantitative detection of proteins and respective PTMs. In this article, Ceglarek et al. [Proteomics Clin. Appl. 2013, 7, 794-801] present an LC-MS-based method for simultaneous quantitation of seven apolipoproteins in serum specimens. The assay fulfills many necessities of routine diagnostic applications, namely, low cost, high throughput, and good reproducibility. We anticipate that validation of new biomarkers will speed up with this technology and the palette of laboratory-based diagnostic tools will hopefully be augmented significantly in the near future. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Three-dimensional virtual bronchoscopy using a tablet computer to guide real-time transbronchial needle aspiration.

PubMed

Fiorelli, Alfonso; Raucci, Antonio; Cascone, Roberto; Reginelli, Alfonso; Di Natale, Davide; Santoriello, Carlo; Capuozzo, Antonio; Grassi, Roberto; Serra, Nicola; Polverino, Mario; Santini, Mario

2017-04-01

We proposed a new virtual bronchoscopy tool to improve the accuracy of traditional transbronchial needle aspiration for mediastinal staging. Chest-computed tomographic images (1 mm thickness) were reconstructed with Osirix software to produce a virtual bronchoscopic simulation. The target adenopathy was identified by measuring its distance from the carina on multiplanar reconstruction images. The static images were uploaded in iMovie Software, which produced a virtual bronchoscopic movie from the images; the movie was then transferred to a tablet computer to provide real-time guidance during a biopsy. To test the validity of our tool, we divided all consecutive patients undergoing transbronchial needle aspiration retrospectively in two groups based on whether the biopsy was guided by virtual bronchoscopy (virtual bronchoscopy group) or not (traditional group). The intergroup diagnostic yields were statistically compared. Our analysis included 53 patients in the traditional and 53 in the virtual bronchoscopy group. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for the traditional group were 66.6%, 100%, 100%, 10.53% and 67.92%, respectively, and for the virtual bronchoscopy group were 84.31%, 100%, 100%, 20% and 84.91%, respectively. The sensitivity ( P  = 0.011) and diagnostic accuracy ( P  = 0.011) of sampling the paratracheal station were better for the virtual bronchoscopy group than for the traditional group; no significant differences were found for the subcarinal lymph node. Our tool is simple, economic and available in all centres. It guided in real time the needle insertion, thereby improving the accuracy of traditional transbronchial needle aspiration, especially when target lesions are located in a difficult site like the paratracheal station. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Ga-68-DOTA-TATE PET/CT for discrimination of tumors of the optic pathway.

PubMed

Klingenstein, Annemarie; Haug, Alexander R; Miller, Christina; Hintschich, Christoph

2015-02-01

Symptomatic tumors of the optic nerve pathway may endanger vision. They are difficult to classify by imaging alone and biopsy may damage visual function. Tumor pathology influences treatment decision and a diagnostic tool with a high sensitivity and specificity would therefore be invaluable. We hypothesized that Ga-68-DOTA-TATE PET/CT may help in discriminating optic nerve tumors as uptake of somatostatin is elevated in meningiomas. Ga-68-DOTA-TATE PET/CT was used to examine 13 patients with ambiguous, symptomatic lesions of the optic pathway for treatment planning. The presence or absence of meningioma was validated by histopathology or supplementary diagnostic work-up. Ga-68-DOTA-TATE PET/CT identified 10 meningiomas (en plaque = 1, optic nerve sheath = 4, sphenoidal = 5) correctly via increased SSTR (somatostatin receptor) expression (mean SUVmax (maximum standardized uptake value) = 14.3 ± 15.4). 3 tumors did not show elevated Ga-68-DOTA-TATE uptake (SUVmax = 2.1 ± 1.0). Subsumizing all clinical-radiological follow-up tools available, these lesions were classified as an intracerebral metastasis of an advanced gastric carcinoma, histologically proven inflammatory collagenous connective tissue and presumed leukemic infiltration of a newly diagnosed chronic lymphocytic leukemia. In this case series, Ga-68-DOTA-TATE PET/CT demonstrated both a sensitivity and specificity of 100%. Yet, the golden standard of histopathology was only available in a subset of patients included. Ga-68-DOTA-TATE PET/CT proved to be a valuable diagnostic tool for the correct classification of equivocal, symptomatic tumors of the anterior optic pathway requiring therapy. PET/CT results influenced therapy decision essentially in all cases.

Sensitivity and specificity of the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and the Intensive Care Delirium Screening Checklist (ICDSC) for detecting post-cardiac surgery delirium: A single-center study in Japan.

PubMed

Nishimura, Katsuji; Yokoyama, Kanako; Yamauchi, Noriko; Koizumi, Masako; Harasawa, Nozomi; Yasuda, Taeko; Mimura, Chizuru; Igita, Hazuki; Suzuki, Eriko; Uchiide, Yoko; Seino, Yusuke; Nomura, Minoru; Yamazaki, Kenji; Ishigooka, Jun

2016-01-01

To compare the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and the Intensive Care Delirium Screening Checklist (ICDSC) for detecting post-cardiac surgery delirium. These tools have not been tested in a specialized cardio-surgical ICU. Sensitivities and specificities of each tool were assessed in a cardio-surgical ICU in Japan by two trained nurses independently. Results were compared with delirium diagnosed by psychiatrists using the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision. There were 110 daily, paired assessments in 31 patients. The CAM-ICU showed 38% sensitivity and 100% specificity for both nurses. All 20 false-negative cases resulted from high scores in the auditory attention screening in CAM-ICU. The ICDSC showed 97% and 94% sensitivity, and 97% and 91% specificity for the two nurses (cutoff ≥4). In a Japanese cardio-surgical ICU, the ICDSC had a higher sensitivity than the CAM-ICU. Copyright © 2016 Elsevier Inc. All rights reserved.

Clinical usefulness of a biomarker-based diagnostic test for acute stroke: the Biomarker Rapid Assessment in Ischemic Injury (BRAIN) study.

PubMed

Laskowitz, Daniel T; Kasner, Scott E; Saver, Jeffrey; Remmel, Kerri S; Jauch, Edward C

2009-01-01

One of the significant limitations in the evaluation and management of patients with suspected acute cerebral ischemia is the absence of a widely available, rapid, and sensitive diagnostic test. The objective of the current study was to assess whether a test using a panel of biomarkers might provide useful diagnostic information in the early evaluation of stroke by differentiating patients with cerebral ischemia from other causes of acute neurological deficit. A total of 1146 patients presenting with neurological symptoms consistent with possible stroke were prospectively enrolled at 17 different sites. Timed blood samples were assayed for matrix metalloproteinase 9, brain natriuretic factor, d-dimer, and protein S100beta. A separate cohort of 343 patients was independently enrolled to validate the multiple biomarker model approach. A diagnostic tool incorporating the values of matrix metalloproteinase 9, brain natriuretic factor, d-dimer, and S-100beta into a composite score was sensitive for acute cerebral ischemia. The multivariate model demonstrated modest discriminative capabilities with an area under the receiver operating characteristic curve of 0.76 for hemorrhagic stroke and 0.69 for all stroke (likelihood test P<0.001). When the threshold for the logistic model was set at the first quartile, this resulted in a sensitivity of 86% for detecting all stroke and a sensitivity of 94% for detecting hemorrhagic stroke. Moreover, results were reproducible in a separate cohort tested on a point-of-care platform. These results suggest that a biomarker panel may add valuable and time-sensitive diagnostic information in the early evaluation of stroke. Such an approach is feasible on a point-of-care platform. The rapid identification of patients with suspected stroke would expand the availability of time-limited treatment strategies. Although the diagnostic accuracy of the current panel is clearly imperfect, this study demonstrates the feasibility of incorporating a biomarker based point-of-care algorithm with readily available clinical data to aid in the early evaluation and management of patients at high risk for cerebral ischemia.

Evaluation of phenotypic detection methods for metallo-β-lactamases (MBLs) in clinical isolates of Pseudomonas aeruginosa.

PubMed

Peter, S; Lacher, A; Marschal, M; Hölzl, F; Buhl, M; Autenrieth, I; Kaase, M; Willmann, M

2014-07-01

Metallo-beta-lactamase (MBL) production in Pseudomonas aeruginosa is a growing issue across the globe. Fast and reliable diagnostic tools are needed for appropriate implementation of infection control measures. In this study we evaluated the performance of three commercial combined disk tests, two EDTA based in-house combined disk tests and the Carba NP test in comparison to molecular detection of MBL genes on 133 meropenem non-susceptible non-duplicate P. aeruginosa clinical isolates. The meropenem/DPA based commercial KPC + MBL-confirm ID kit (Rosco Diagnostica, Denmark) and the MASTDISCS™ ID carbapenemase (Enterobacteriaceae) detection disc set (MAST Diagnostics, UK) showed sensitivities of 31.1 % and 28.8 % and specificities of 69.3 % and 79.6 %, respectively. The total MBL confirm kit (Rosco Diagnostica, Denmark) contains imipenem/DPA and imipenem/EDTA combination disks. Evaluation of the single disk combinations revealed 84.4 % sensitivity and 81.8 % specificity for the imipenem/DPA assay and 86.7 % sensitivity and 51.1 % specificity for the imipenem/EDTA test. Applying both tests simultaneously resulted in a slightly higher sensitivity of 88.9 % but a lower specificity of 48.9 % when compared to the single tests alone. The Carba NP test showed 93.3 % sensitivity and 96.6 % specificity. All phenotypic combined disk tests lacked either sensitivity or specificity for the detection of MBL in P. aeruginosa. The Carba NP test showed excellent test properties, but suffers from drawbacks in handling and high costs. The optimal diagnostic approach needs to be chosen depending on the epidemiological situation, laboratory resources and availability of molecular confirmation tests.

Unenhanced breast MRI (STIR, T2-weighted TSE, DWIBS): An accurate and alternative strategy for detecting and differentiating breast lesions.

PubMed

Telegrafo, Michele; Rella, Leonarda; Stabile Ianora, Amato Antonio; Angelelli, Giuseppe; Moschetta, Marco

2015-10-01

To assess the role of STIR, T2-weighted TSE and DWIBS sequences for detecting and characterizing breast lesions and to compare unenhanced (UE)-MRI results with contrast-enhanced (CE)-MRI and histological findings, having the latter as the reference standard. Two hundred eighty consecutive patients (age range, 27-73 years; mean age±standard deviation (SD), 48.8±9.8years) underwent MR examination with a diagnostic protocol including STIR, T2-weighted TSE, THRIVE and DWIBS sequences. Two radiologists blinded to both dynamic sequences and histological findings evaluated in consensus STIR, T2-weighted TSE and DWIBS sequences and after two weeks CE-MRI images searching for breast lesions. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy for UE-MRI and CE-MRI were calculated. UE-MRI results were also compared with CE- MRI. UE-MRI sequences obtained sensitivity, specificity, diagnostic accuracy, PPV and NPV values of 94%, 79%, 86%, 79% and 94%, respectively. CE-MRI sequences obtained sensitivity, specificity, diagnostic accuracy, PPV and NPV values of 98%, 83%, 90%, 84% and 98%, respectively. No statistically significant difference between UE-MRI and CE-MRI was found. Breast UE-MRI could represent an accurate diagnostic tool and a valid alternative to CE-MRI for evaluating breast lesions. STIR and DWIBS sequences allow to detect breast lesions while T2-weighted TSE sequences and ADC values could be useful for lesion characterization. Copyright © 2015 Elsevier Inc. All rights reserved.

Diagnostic Accuracy of Rating Scales for Attention-Deficit/Hyperactivity Disorder: A Meta-analysis.

PubMed

Chang, Ling-Yin; Wang, Mei-Yeh; Tsai, Pei-Shan

2016-03-01

The Child Behavior Checklist-Attention Problem (CBCL-AP) scale and Conners Rating Scale-Revised (CRS-R) are commonly used behavioral rating scales for diagnosing attention-deficit/hyperactivity disorder (ADHD) in children and adolescents. To evaluate and compare the diagnostic performance of CBCL-AP and CRS-R in diagnosing ADHD in children and adolescents. PubMed, Ovid Medline, and other relevant electronic databases were searched for articles published up to May 2015. We included studies evaluating the diagnostic performance of either CBCL-AP scale or CRS-R for diagnosing ADHD in pediatric populations in comparison with a defined reference standard. Bivariate random effects models were used for pooling and comparing diagnostic performance. We identified and evaluated 14 and 11 articles on CBCL-AP and CRS-R, respectively. The results revealed pooled sensitivities of 0.77, 0.75, 0.72, and 0.83 and pooled specificities of 0.73, 0.75, 0.84, and 0.84 for CBCL-AP, Conners Parent Rating Scale-Revised, Conners Teacher Rating Scale-Revised, and Conners Abbreviated Symptom Questionnaire (ASQ), respectively. No difference was observed in the diagnostic performance of the various scales. Study location, age of participants, and percentage of female participants explained the heterogeneity in the specificity of the CBCL-AP. CBCL-AP and CRS-R both yielded moderate sensitivity and specificity in diagnosing ADHD. According to the comparable diagnostic performance of all examined scales, ASQ may be the most effective diagnostic tool in assessing ADHD because of its brevity and high diagnostic accuracy. CBCL is recommended for more comprehensive assessments. Copyright © 2016 by the American Academy of Pediatrics.

Molecular Diagnosis of Orthopedic-Device-Related Infection Directly from Sonication Fluid by Metagenomic Sequencing

PubMed Central

Sanderson, Nicholas D.; Atkins, Bridget L.; Brent, Andrew J.; Cole, Kevin; Foster, Dona; McNally, Martin A.; Oakley, Sarah; Peto, Leon; Taylor, Adrian; Peto, Tim E. A.; Crook, Derrick W.; Eyre, David W.

2017-01-01

ABSTRACT Culture of multiple periprosthetic tissue samples is the current gold standard for microbiological diagnosis of prosthetic joint infections (PJI). Additional diagnostic information may be obtained through culture of sonication fluid from explants. However, current techniques can have relatively low sensitivity, with prior antimicrobial therapy and infection by fastidious organisms influencing results. We assessed if metagenomic sequencing of total DNA extracts obtained direct from sonication fluid can provide an alternative rapid and sensitive tool for diagnosis of PJI. We compared metagenomic sequencing with standard aerobic and anaerobic culture in 97 sonication fluid samples from prosthetic joint and other orthopedic device infections. Reads from Illumina MiSeq sequencing were taxonomically classified using Kraken. Using 50 derivation samples, we determined optimal thresholds for the number and proportion of bacterial reads required to identify an infection and confirmed our findings in 47 independent validation samples. Compared to results from sonication fluid culture, the species-level sensitivity of metagenomic sequencing was 61/69 (88%; 95% confidence interval [CI], 77 to 94%; for derivation samples 35/38 [92%; 95% CI, 79 to 98%]; for validation samples, 26/31 [84%; 95% CI, 66 to 95%]), and genus-level sensitivity was 64/69 (93%; 95% CI, 84 to 98%). Species-level specificity, adjusting for plausible fastidious causes of infection, species found in concurrently obtained tissue samples, and prior antibiotics, was 85/97 (88%; 95% CI, 79 to 93%; for derivation samples, 43/50 [86%; 95% CI, 73 to 94%]; for validation samples, 42/47 [89%; 95% CI, 77 to 96%]). High levels of human DNA contamination were seen despite the use of laboratory methods to remove it. Rigorous laboratory good practice was required to minimize bacterial DNA contamination. We demonstrate that metagenomic sequencing can provide accurate diagnostic information in PJI. Our findings, combined with the increasing availability of portable, random-access sequencing technology, offer the potential to translate metagenomic sequencing into a rapid diagnostic tool in PJI. PMID:28490492

Loop-Mediated Isothermal Amplification Test for Trypanosoma gambiense Group 1 with Stem Primers: A Molecular Xenomonitoring Test for Sleeping Sickness.

PubMed

Njiru, Zablon K; Mbae, Cecilia K; Mburugu, Gitonga N

2017-01-01

The World Health Organization has targeted Human African Trypanosomiasis (HAT) for elimination by 2020 with zero incidence by 2030. To achieve and sustain this goal, accurate and easy-to-deploy diagnostic tests for Gambian trypanosomiasis which accounts for over 98% of reported cases will play a crucial role. Most needed will be tools for surveillance of pathogen in vectors (xenomonitoring) since population screening tests are readily available. The development of new tests is expensive and takes a long time while incremental improvement of existing technologies that have potential for xenomonitoring may offer a shorter pathway to tools for HAT surveillance. We have investigated the effect of including a second set of reaction accelerating primers (stem primers) to the standard T. brucei gambiense LAMP test format. The new test format was analyzed with and without outer primers. Amplification was carried out using Rotorgene 6000 and the portable ESE Quant amplification unit capable of real-time data output. The stem LAMP formats indicated shorter time to results (~8 min), were 10-100-fold more sensitive, and indicated higher diagnostic sensitivity and accuracy compared to the standard LAMP test. It was possible to confirm the predicted product using ESE melt curves demonstrating the potential of combining LAMP and real-time technologies as possible tool for HAT molecular xenomonitoring.

Critical comparison of diffuse reflectance spectroscopy and colorimetry as dermatological diagnostic tools for acanthosis nigricans: a chemometric approach.

PubMed

Devpura, Suneetha; Pattamadilok, Bensachee; Syed, Zain U; Vemulapalli, Pranita; Henderson, Marsha; Rehse, Steven J; Hamzavi, Iltefat; Lim, Henry W; Naik, Ratna

2011-06-01

Quantification of skin changes due to acanthosis nigricans (AN), a disorder common among insulin-resistant diabetic and obese individuals, was investigated using two optical techniques: diffuse reflectance spectroscopy (DRS) and colorimetry. Measurements were obtained from AN lesions on the neck and two control sites of eight AN patients. A principal component/discriminant function analysis successfully differentiated between AN lesion and normal skin with 87.7% sensitivity and 94.8% specificity in DRS measurements and 97.2% sensitivity and 96.4% specificity in colorimetry measurements.

Sensitivity and specificity of a briefer version of the Cambridge Cognitive Examination (CAMCog-Short) in the detection of cognitive decline in the elderly: An exploratory study.

PubMed

Radanovic, Marcia; Facco, Giuliana; Forlenza, Orestes V

2018-05-01

To create a reduced and briefer version of the widely used Cambridge Cognitive Examination (CAMCog) battery as a concise cognitive test to be used in primary and secondary levels of health care to detect cognitive decline. Our aim was to reduce the administration time of the original test while maintaining its diagnostic accuracy. On the basis of the analysis of 835 CAMCog tests performed by 429 subjects (107 controls, 192 mild cognitive impairment [MCI], and 130 dementia patients), we extracted items that most contributed to intergroup differentiation, according to 2 educational levels (≤8 and >8 y of formal schooling). The final 33-item "low education" and 24-item"high education" CAMCog-Short correspond to 48.5% and 35% of the original version and yielded similar rates of accuracy: area under ROC curves (AUC) > 0.9 in the differentiation between controls × dementia and MCI × dementia (sensitivities > 75%; specificities > 90%); AUC > 0.7 for the differentiation between controls and MCI (sensitivities > 65%; specificities > 75%). The CAMCog-Short emerges as a promising tool for a brief, yet sufficiently accurate, screening tool for use in clinical settings. Further prospective studies designed to validate its diagnostic accuracy are needed. Copyright © 2018 John Wiley & Sons, Ltd.

The diagnostic accuracy of magnetic resonance venography in the detection of deep venous thrombosis: a systematic review and meta-analysis.

PubMed

Abdalla, G; Fawzi Matuk, R; Venugopal, V; Verde, F; Magnuson, T H; Schweitzer, M A; Steele, K E

2015-08-01

To search the literature for further evidence for the use of magnetic resonance venography (MRV) in the detection of suspected DVT and to re-evaluate the accuracy of MRV in the detection of suspected deep vein thrombosis (DVT). PubMed, EMBASE, Scopus, Cochrane, and Web of Science were searched. Study quality and the risk of bias were evaluated using the QUADAS 2. A random effects meta-analysis including subgroup and sensitivity analyses were performed. The search resulted in 23 observational studies all from academic centres. Sixteen articles were included in the meta-analysis. The summary estimates for MRV as a diagnostic non-invasive tool revealed a sensitivity of 93% (95% confidence interval [CI]: 89% to 95%) and specificity of 96% (95% CI: 94% to 97%). The heterogeneity of the studies was high. Inconsistency (I2) for sensitivity and specificity was 80.7% and 77.9%, respectively. Further studies investigating the use of MRV in the detection of suspected DVT did not offer further evidence to support the replacement of ultrasound with MRV as the first-line investigation. However, MRV may offer an alternative tool in the detection/diagnosis of DVT for whom ultrasound is inadequate or not feasible (such as in the obese patient). Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Serum Adenosine Deaminase (ADA) Activity: A Novel Screening Test to Differentiate HIV Monoinfection From HIV-HBV and HIV-HCV Coinfections.

PubMed

Abdi, Mohammad; Rahbari, Rizgar; Khatooni, Zahed; Naseri, Nima; Najafi, Adel; Khodadadi, Iraj

2016-05-01

CD4(+) cell count, the common HIV infection screening test, is costly and unable to differentiate HIV monoinfection from its concurrent infection with hepatitis B or C virus. We aimed to ascertain diagnostic value of serum adenosine deaminase (ADA) activity as a useful tool to differentiate HIV mono- and co-infection. Blood samples were collected from 30 HIV-HBV and 30 HIV-HCV coinfected patients, 33 HIV positive subjects, and 72 controls. CD4(+) cell count, serum total ADA (tADA), and ADA1, and ADA2 isoenzyme activities were determined and their sensitivity and specificity were computed. tADA and ADA2 activities were significantly higher and CD4(+) counts were markedly lower in all patients compared with controls. Strong inverse agreements between CD4(+) cell counts and both tADA and ADA2 activities were observed. Serum tADA and ADA1 activities showed the highest specificity and the highest sensitivity, respectively, for differentiating HIV monoinfection from HIV-HBV and HIV-HCV coinfections. We showed strong agreement and correlation between CD4(+) cell count and ADA enzyme activity. Based on high ADA sensitivity and specificity, it is concluded that determination of ADA activity might be a novel diagnostic tool to distinguish of HIV monoinfection from its coinfection with HBV or HCV. © 2015 Wiley Periodicals, Inc.

Field evaluation of the photo-induced electron transfer fluorogenic primers (PET) real-time PCR for the detection of Plasmodium falciparum in Tanzania

PubMed Central

2014-01-01

Background Accurate diagnosis of malaria infections remains challenging, especially in the identification of submicroscopic infections. New molecular diagnostic tools that are inexpensive, sensitive enough to detect low-level infections and suitable in laboratory settings of resource-limited countries are required for malaria control and elimination programmes. Here the diagnostic potential of a recently developed photo-induced electron transfer fluorogenic primer (PET) real-time polymerase chain reaction (PCR) called PET-PCR was investigated. This study aimed to (i) evaluate the use of this assay as a method for the detection of both Plasmodium falciparum and other Plasmodium species infections in a developing country’s diagnostic laboratory; and, (ii) determine the assay’s sensitivity and specificity compared to a nested 18S rRNA PCR. Methods Samples used in this study were obtained from a previous study conducted in the region of Iringa, Tanzania. A total of 303 samples from eight health facilities in Tanzania were utilized for this evaluation. All samples were screened using the multiplex PET-PCR assay designed to detect Plasmodium genus and P. falciparum initially in laboratory in Tanzania and then repeated at a reference laboratory at the CDC in the USA. Microscopy data was available for all the 303 samples. A subset of the samples were tested in a blinded fashion to find the sensitivity and specificity of the PET-PCR compared to the nested 18S rRNA PCR. Results Compared to microscopy, the PET-PCR assay was 59% more sensitive in detecting P. falciparum infections. The observed sensitivity and specificity were 100% (95% confidence interval (CI0.95) = 94-100%) and (CI0.95 = 96-100%), respectively, for the PET-PCR assay when compared to nested 18S rRNA PCR. When compared to 18S rRNA PCR, microscopy had a low sensitivity of 40% (CI0.95 = 23-61%) and specificity of 100% (CI0.95 = 96-100%). The PET-PCR results performed in the field laboratory in Tanzania were in 100% concordance with the results obtained at the reference laboratory in the USA. Conclusion The PET-PCR is a new molecular diagnostic tool with similar performance characteristics as commonly used PCR methods that is less expensive, easy to use, and amiable to large scale-surveillance studies in developing country settings. PMID:24467985

Diagnosis of TIA (DOT) score--design and validation of a new clinical diagnostic tool for transient ischaemic attack.

PubMed

Dutta, Dipankar

2016-02-09

The diagnosis of Transient Ischaemic Attack (TIA) can be difficult and 50-60% of patients seen in TIA clinics turn out to be mimics. Many of these mimics have high ABCD2 scores and fill urgent TIA clinic slots inappropriately. A TIA diagnostic tool may help non-specialists make the diagnosis with greater accuracy and improve TIA clinic triage. The only available diagnostic score (Dawson et al) is limited in scope and not widely used. The Diagnosis of TIA (DOT) Score is a new and internally validated web and mobile app based diagnostic tool which encompasses both brain and retinal TIA. The score was derived retrospectively from a single centre TIA clinic database using stepwise logistic regression by backwards elimination to find the best model. An optimum cutpoint was obtained for the score. The derivation and validation cohorts were separate samples drawn from the years 2010/12 and 2013 respectively. Receiver Operating Characteristic (ROC) curves and area under the curve (AUC) were calculated and the diagnostic accuracy of DOT was compared to the Dawson score. A web and smartphone calculator were designed subsequently. The derivation cohort had 879 patients and the validation cohort 525. The final model had seventeen predictors and had an AUC of 0.91 (95% CI: 0.89-0.93). When tested on the validation cohort, the AUC for DOTS was 0.89 (0.86-0.92) while that of the Dawson score was 0.77 (0.73-0.81). The sensitivity and specificity of the DOT score were 89% (CI: 84%-93%) and 76% (70%-81%) respectively while those of the Dawson score were 83% (78%-88%) and 51% (45%-57%). Other diagnostic accuracy measures (DOT vs. Dawson) include positive predictive values (75% vs. 58%), negative predictive values (89% vs. 79%), positive likelihood ratios (3.67 vs. 1.70) and negative likelihood ratios (0.15 vs. 0.32). The DOT score shows promise as a diagnostic tool for TIA and requires independent external validation before it can be widely used. It could potentially improve the triage of patients assessed for suspected TIA.

Sensitivity and Specificity of Long Wave Infrared Imaging for Attention-Deficit/Hyperactivity Disorder

ERIC Educational Resources Information Center

Coben, Robert; Myers, Thomas E.

2009-01-01

Objective: This study was the first to investigate the efficacy of long wave infrared (LWIR) imaging as a diagnostic tool for ADHD. Method: with ADHD and a high level of specificity (94%) in discriminating those with ADHD from those with other diagnoses. The overall classification rate was 73.16%. This was indicative of a high level of…

Diagnostic Accuracy of Repetition Tasks for the Identification of Specific Language Impairment (SLI) in Bilingual Children: Evidence from Russian and Hebrew

ERIC Educational Resources Information Center

Armon-Lotem, Sharon; Meir, Natalia

2016-01-01

Background: Previous research demonstrates that repetition tasks are valuable tools for diagnosing specific language impairment (SLI) in monolingual children in English and a variety of other languages, with non-word repetition (NWR) and sentence repetition (SRep) yielding high levels of sensitivity and specificity. Yet, only a few studies have…

Microfluidics-Based Lab-on-Chip Systems in DNA-Based Biosensing: An Overview

PubMed Central

Dutse, Sabo Wada; Yusof, Nor Azah

2011-01-01

Microfluidics-based lab-on-chip (LOC) systems are an active research area that is revolutionising high-throughput sequencing for the fast, sensitive and accurate detection of a variety of pathogens. LOCs also serve as portable diagnostic tools. The devices provide optimum control of nanolitre volumes of fluids and integrate various bioassay operations that allow the devices to rapidly sense pathogenic threat agents for environmental monitoring. LOC systems, such as microfluidic biochips, offer advantages compared to conventional identification procedures that are tedious, expensive and time consuming. This paper aims to provide a broad overview of the need for devices that are easy to operate, sensitive, fast, portable and sufficiently reliable to be used as complementary tools for the control of pathogenic agents that damage the environment. PMID:22163925

Predictive Ability of an Emergency Medical Dispatch Stroke Diagnostic Tool in Identifying Hospital-Confirmed Strokes.

PubMed

Clawson, Jeff J; Scott, Greg; Gardett, Isabel; Youngquist, Scott; Taillac, Peter; Fivaz, Conrad; Olola, Christopher

2016-08-01

Early hospital notification of a possible stroke arriving via emergency medical services (EMS) can prepare stroke center personnel for timely treatment, especially timely administration of tissue plasminogen activator. Stroke center notification from the emergency dispatch center-before responders reach the scene-may promote even earlier and faster system activation, meaning that stroke center teams may be ready to receive patients as soon as the ambulance arrives. This study evaluates the use of a Medical Priority Dispatch System (MPDS; Priority Dispatch Corp., Salt Lake City, UT) Stroke Diagnostic Tool (SDxT) to identify possible strokes early by comparing the tools' results to on-scene and hospital findings. The retrospective descriptive study utilized stroke data from 3 sources: emergency medical dispatch, EMS, and emergency department/hospital. A total of 830 cases were collected between June 2012 and December 2013, of which 603 (72.7%) had matching dispatch records. Of the 603 cases, 304 (50.4%) were handled using MPDS Stroke Protocol 28. The SDxT had an 86.4% ability (OR [95% CI]: 2.3 [1.5, 3.5]) to effectively identify strokes among all the hospital-confirmed stroke cases (sensitivity), and a 26.6% ability to effectively identify nonstrokes among all the hospital-confirmed nonstroke cases (specificity). The SDxT demonstrated a very high sensitivity, compared to similar tools used in the field and at dispatch. The specificity was somewhat low, but this was expected-and is intended in the creation of protocols to be used over the phone in emergency situations. The tool is a valuable method for identifying strokes early and may allow early hospital notification. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Performance of in silico prediction tools for the classification of rare BRCA1/2 missense variants in clinical diagnostics.

PubMed

Ernst, Corinna; Hahnen, Eric; Engel, Christoph; Nothnagel, Michael; Weber, Jonas; Schmutzler, Rita K; Hauke, Jan

2018-03-27

The use of next-generation sequencing approaches in clinical diagnostics has led to a tremendous increase in data and a vast number of variants of uncertain significance that require interpretation. Therefore, prediction of the effects of missense mutations using in silico tools has become a frequently used approach. Aim of this study was to assess the reliability of in silico prediction as a basis for clinical decision making in the context of hereditary breast and/or ovarian cancer. We tested the performance of four prediction tools (Align-GVGD, SIFT, PolyPhen-2, MutationTaster2) using a set of 236 BRCA1/2 missense variants that had previously been classified by expert committees. However, a major pitfall in the creation of a reliable evaluation set for our purpose is the generally accepted classification of BRCA1/2 missense variants using the multifactorial likelihood model, which is partially based on Align-GVGD results. To overcome this drawback we identified 161 variants whose classification is independent of any previous in silico prediction. In addition to the performance as stand-alone tools we examined the sensitivity, specificity, accuracy and Matthews correlation coefficient (MCC) of combined approaches. PolyPhen-2 achieved the lowest sensitivity (0.67), specificity (0.67), accuracy (0.67) and MCC (0.39). Align-GVGD achieved the highest values of specificity (0.92), accuracy (0.92) and MCC (0.73), but was outperformed regarding its sensitivity (0.90) by SIFT (1.00) and MutationTaster2 (1.00). All tools suffered from poor specificities, resulting in an unacceptable proportion of false positive results in a clinical setting. This shortcoming could not be bypassed by combination of these tools. In the best case scenario, 138 families would be affected by the misclassification of neutral variants within the cohort of patients of the German Consortium for Hereditary Breast and Ovarian Cancer. We show that due to low specificities state-of-the-art in silico prediction tools are not suitable to predict pathogenicity of variants of uncertain significance in BRCA1/2. Thus, clinical consequences should never be based solely on in silico forecasts. However, our data suggests that SIFT and MutationTaster2 could be suitable to predict benignity, as both tools did not result in false negative predictions in our analysis.

Diagnostic value of using 18F-FDG PET and PET/CT in immunocompetent patients with primary central nervous system lymphoma: A systematic review and meta-analysis.

PubMed

Zou, Yaru; Tong, Jianjing; Leng, Haiyan; Jiang, Jingwei; Pan, Meng; Chen, Zi

2017-06-20

18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and PET/CT have become two of the most powerful tools for malignant lymphoma exploration, but their diagnostic role in primary central nervous system lymphoma (PCNSL) is still disputed. The purpose of our study is to identify the usefulness of 18F-FDG PET and PET/CT for detecting PCNSL. A total of 129 patients, obtained from eight eligible studies, were included for this systematic review and meta-analysis. The performance of 18F-FDG PET and PET/CT for diagnosing PCNSL were as follows: the pooled sensitivity was 0.88 (95% CI: 0.80-0.94), specificity was 0.86 (95% CI: 0.73-0.94), positive likelihood ratio (PLR) was 3.99 (95% CI: 2.31-6.90), negative likelihood ratio (NLR) was 0.11 (95% CI: 0.04-0.32), and diagnostic odds ratio (DOR) was 33.40 (95% CI: 10.40-107.3). In addition, the area under the curve (AUC) and Q index were 0.9192 and 0.8525, respectively. PubMed/MEDLINE, Embase and Cochrane Library were systematically searched for potential publications (last updated on July 16th, 2016). Reference lists of included articles were also checked. Original articles that reported data on patients who were suspected of having PCNSL were considered suitable for inclusion. The sensitivities and specificities of 18F-FDG PET and PET/CT in each study were evaluated. The Stata software and Meta-Disc software were employed in the process of data analysis. 18F-FDG PET and PET/CT showed considerable accuracy in identifying PCNSL in immunocompetent patients and could be a valuable radiological diagnostic tool for PCNSL.

Lung ultrasound in diagnosing pneumonia in childhood: a systematic review and meta-analysis.

PubMed

Orso, Daniele; Ban, Alessio; Guglielmo, Nicola

2018-06-21

Pneumonia is the third leading cause of death in children under 5 years of age worldwide. In pediatrics, both the accuracy and safety of diagnostic tools are important. Lung ultrasound (LUS) could be a safe diagnostic tool for this reason. We searched in the literature for diagnostic studies about LUS to predict pneumonia in pediatric patients using systematic review and meta-analysis. The Medline, CINAHL, Cochrane Library, Embase, SPORTDiscus, ScienceDirect, and Web of Science databases from inception to September 2017 were searched. All studies that evaluated the diagnostic accuracy of LUS in determining the presence of pneumonia in patients under 18 years of age were included. 1042 articles were found by systematic search. 76 articles were assessed for eligibility. Seventeen studies were included in the systematic review. We included 2612 pooled cases. The age of the pooled sample population ranged from 0 to about 21 years old. Summary sensitivity, specificity, and AUC were 0.94 (IQR: 0.89-0.97), 0.93 (IQR: 0.86-0.98), and 0.98 (IQR: 0.94-0.99), respectively. No agreement on reference standard was detected: nine studies used chest X-rays, while four studies considered the clinical diagnosis. Only one study used computed tomography. LUS seems to be a promise tool for diagnosing pneumonia in children. However, the high heterogeneity found across the individual studies, and the absence of a reliable reference standard, make the finding questionable. More methodologically rigorous studies are needed.

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

Interactive visualisation for interpreting diagnostic test accuracy study results.

PubMed

Fanshawe, Thomas R; Power, Michael; Graziadio, Sara; Ordóñez-Mena, José M; Simpson, John; Allen, Joy

2018-02-01

Information about the performance of diagnostic tests is typically presented in the form of measures of test accuracy such as sensitivity and specificity. These measures may be difficult to translate directly into decisions about patient treatment, for which information presented in the form of probabilities of disease after a positive or a negative test result may be more useful. These probabilities depend on the prevalence of the disease, which is likely to vary between populations. This article aims to clarify the relationship between pre-test (prevalence) and post-test probabilities of disease, and presents two free, online interactive tools to illustrate this relationship. These tools allow probabilities of disease to be compared with decision thresholds above and below which different treatment decisions may be indicated. They are intended to help those involved in communicating information about diagnostic test performance and are likely to be of benefit when teaching these concepts. A substantive example is presented using C reactive protein as a diagnostic marker for bacterial infection in the older adult population. The tools may also be useful for manufacturers of clinical tests in planning product development, for authors of test evaluation studies to improve reporting and for users of test evaluations to facilitate interpretation and application of the results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The diagnostic value of the premature ejaculation diagnostic tool and its association with intravaginal ejaculatory latency time.

PubMed

Kam, Sung Chul; Han, Deok Hyun; Lee, Sung Won

2011-03-01

Premature ejaculation (PE) is the most prevalent male ejaculation disorder. The premature ejaculation diagnostic tool (PEDT) was developed to systematically apply the DSM-IV-TR criteria in diagnostic PE. To evaluate the diagnostic value of the PEDT and its association with intravaginal ejaculatory latency time (IELT). (i) Korean validation of PEDT: data was collected from men interviewed by one of the two clinical experts, who made a diagnostic of present or absence of PE, using DSM-IV-TR criteria. A total of 103 patients with PE and 100 men without PE were enrolled into the study and requested to complete the PEDT; and (ii) The correlation between IELT and PEDT: 200 participants were enrolled and each participant was asked to make out PEDT. All participants were requested to measure IELT. Validity and reliability of the PEDT and its association with IELT. The geometric mean IELT of the PE group was 115.37 ± 78.14 seconds. The number of men reporting IELTs of <1, 1 to ≤ 2, and >2 minutes were 28 (28.6%), 29 (29.6%), and 41 (41.8%), respectively. The Cronbach's alpha score was calculated as 0.93, showing adequate internal consistency. The test-retest correlation coefficients of each item were higher than 0.72 and the correlation coefficients of the total score was 0.88. (P < 0.001) Sensitivity and specificity analyses suggested a score of ≤ 8 indicated no PE, 9 and 10 probable PE, and ≥ 11 PE. The PEDT total score and IELT showed an adequate negative correlation. (ρ = -0.77, P < 0.0001) also, the PEDT total score of the PE subgroup (IELT ≤ 2 minutes) and IELT showed a negative correlation. (ρ = -0.6, P < 0.0001) The PEDT was highly effective in detecting the presence of PE. The result of our study supports its validity as a diagnostic tool in the clinical setting. © 2010 International Society for Sexual Medicine.

Self-diagnosis of active head lice infestation by individuals from an impoverished community: high sensitivity and specificity.

PubMed

Pilger, Daniel; Khakban, Adak; Heukelbach, Jorg; Feldmeier, Hermann

2008-01-01

To compare sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of self-diagnosis for head lice infestation with visual inspection, we conducted a study in an urban slum in Brazil. Individuals were asked about active head lice infestation (self-diagnosis); we performed visual inspection and thereafter wet combing (gold standard). Of the 175 individuals included, 77 (44%) had an active head lice infestation. For self-diagnosis, sensitivity (80.5%), specificity (91.8%), PPV (88.6%) and NPV (85.7%) were high. Sensitivity of visual inspection was 35.1%. Public health professionals can use self-diagnosis as a diagnostic tool, to estimate accurately prevalence of pediculosis in a community, and to monitor ongoing intervention strategies.

Current ante-mortem techniques for diagnosis of bovine tuberculosis.

PubMed

Bezos, Javier; Casal, Carmen; Romero, Beatriz; Schroeder, Bjoern; Hardegger, Roland; Raeber, Alex J; López, Lissette; Rueda, Paloma; Domínguez, Lucas

2014-10-01

Bovine tuberculosis (TB), mainly caused by Mycobacterium bovis, is a zoonotic disease with implications for Public Health and having an economic impact due to decreased production and limitations to the trade. Bovine TB is subjected to official eradication campaigns mainly based on a test and slaughter policy using diagnostic assays based on the cell-mediated immune response as the intradermal tuberculin test and the gamma-interferon (IFN-γ) assay. Moreover, several diagnostic assays based on the detection of specific antibodies (Abs) have been developed in the last few years with the aim of complementing the current diagnostic techniques in the near future. This review provides an overview of the current ante-mortem diagnostic tools for diagnosis of bovine TB regarding historical background, methodologies and sensitivity (Se) and specificity (Sp) obtained in previous studies under different epidemiological situations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Diagnostic accuracy of scapular physical examination tests for shoulder disorders: a systematic review.

PubMed

Wright, Alexis A; Wassinger, Craig A; Frank, Mason; Michener, Lori A; Hegedus, Eric J

2013-09-01

To systematically review and critique the evidence regarding the diagnostic accuracy of physical examination tests for the scapula in patients with shoulder disorders. A systematic, computerised literature search of PubMED, EMBASE, CINAHL and the Cochrane Library databases (from database inception through January 2012) using keywords related to diagnostic accuracy of physical examination tests of the scapula. The Quality Assessment of Diagnostic Accuracy Studies tool was used to critique the quality of each paper. Eight articles met the inclusion criteria; three were considered to be of high quality. Of the three high-quality studies, two were in reference to a 'diagnosis' of shoulder pain. Only one high-quality article referenced specific shoulder pathology of acromioclavicular dislocation with reported sensitivity of 71% and 41% for the scapular dyskinesis and SICK scapula test, respectively. Overall, no physical examination test of the scapula was found to be useful in differentially diagnosing pathologies of the shoulder.

Detection of spring viraemia of carp virus (SVCV) by loop-mediated isothermal amplification (LAMP) in koi carp, Cyprinus carpio L

USGS Publications Warehouse

Shivappa, R.B.; Savan, R.; Kono, T.; Sakai, M.; Emmenegger, E.; Kurath, G.; Levine, Jay F.

2008-01-01

Spring viraemia of carp virus (SVCV) is a rhabdovirus associated with systemic illness and mortality in cyprinids. Several diagnostic tests are available for detection of SVCV. However, most of these tests are time consuming and are not well adapted for field-based diagnostics. In this study, a diagnostic tool for SVCV detection based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) has been developed. Based on the nucleotide sequence of the glycoprotein (G) gene of SVCV North Carolina (NC) isolate, four sets (each set containing two outer and two inner) of primers were designed. Temperature and time conditions were optimized to 65 ??C and 60 min, respectively, for LAMP and RT-LAMP using one primer set. In vitro specificity was evaluated using four different strains of fish rhabdoviruses and RT-LAMP was found to be specific to SVCV. Serial dilutions of SVCV NC isolate was used to evaluate the in vitro sensitivity of RT-LAMP. Sensitivity of the assays was similar to RT-PCR and detected SVCV even at the lowest dilution of 10 1 TCID50 mL-1. The ability of RT-LAMP to detect SVCV from infected carp was also tested and the assay detected SVCV from all infected fish. The isothermal temperature requirements, high specificity and sensitivity, and short incubation time of the RT-LAMP assay make it an excellent choice as a field diagnostic test for SVCV. ?? 2008 The Authors.

Nutritional screening in hospitalized pediatric patients: a systematic review.

PubMed

Teixeira, Adriana Fonseca; Viana, Kátia Danielle Araújo Lourenço

2016-01-01

This systematic review aimed to verify the available scientific evidence on the clinical performance and diagnostic accuracy of nutritional screening tools in hospitalized pediatric patients. A search was performed in the Medline (National Library of Medicine United States), LILACS (Latin American and Caribbean Health Sciences), PubMed (US National Library of Medicine National Institutes of Health), in the SCIELO (Scientific Electronic Library Online), through CAPES portal (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior), bases Scopus e Web of Science. The descriptors used in accordance with the Descriptors in Health Sciences (DeCS)/Medical Subject Headings (MeSH) list were "malnutrition", "screening", and "pediatrics", as well as the equivalent words in Portuguese. The authors identified 270 articles published between 2004 and 2014. After applying the selection criteria, 35 were analyzed in full and eight articles were included in the systematic review. We evaluated the methodological quality of the studies using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS). Five nutritional screening tools in pediatrics were identified. Among these, the Screening Tool for the Assessment of Malnutrition in Pediatrics (STAMP) showed high sensitivity, almost perfect inter-rater agreement and between the screening and the reference standard; the Screening Tool Risk on Nutritional Status and Growth (STRONGkids) showed high sensitivity, lower percentage of specificity, substantial intra-rater agreement, and ease of use in clinical practice. The studies included in this systematic review showed good performance of the nutritional screening tools in pediatrics, especially STRONGkids and STAMP. The authors emphasize the need to perform for more studies in this area. Only one tool was translated and adapted to the Brazilian pediatric population, and it is essential to carry out studies of tool adaptation and validation for this population. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

The Diagnostic Validity and Reliability of an Internet-Based Clinical Assessment Program for Mental Disorders

PubMed Central

Klein, Britt; Meyer, Denny; Austin, David William; Abbott, Jo-Anne M

2015-01-01

Background Internet-based assessment has the potential to assist with the diagnosis of mental health disorders and overcome the barriers associated with traditional services (eg, cost, stigma, distance). Further to existing online screening programs available, there is an opportunity to deliver more comprehensive and accurate diagnostic tools to supplement the assessment and treatment of mental health disorders. Objective The aim was to evaluate the diagnostic criterion validity and test-retest reliability of the electronic Psychological Assessment System (e-PASS), an online, self-report, multidisorder, clinical assessment and referral system. Methods Participants were 616 adults residing in Australia, recruited online, and representing prospective e-PASS users. Following e-PASS completion, 158 participants underwent a telephone-administered structured clinical interview and 39 participants repeated the e-PASS within 25 days of initial completion. Results With structured clinical interview results serving as the gold standard, diagnostic agreement with the e-PASS varied considerably from fair (eg, generalized anxiety disorder: κ=.37) to strong (eg, panic disorder: κ=.62). Although the e-PASS’ sensitivity also varied (0.43-0.86) the specificity was generally high (0.68-1.00). The e-PASS sensitivity generally improved when reducing the e-PASS threshold to a subclinical result. Test-retest reliability ranged from moderate (eg, specific phobia: κ=.54) to substantial (eg, bulimia nervosa: κ=.87). Conclusions The e-PASS produces reliable diagnostic results and performs generally well in excluding mental disorders, although at the expense of sensitivity. For screening purposes, the e-PASS subclinical result generally appears better than a clinical result as a diagnostic indicator. Further development and evaluation is needed to support the use of online diagnostic assessment programs for mental disorders. Trial Registration Australian and New Zealand Clinical Trials Registry ACTRN121611000704998; http://www.anzctr.org.au/trial_view.aspx?ID=336143 (Archived by WebCite at http://www.webcitation.org/618r3wvOG). PMID:26392066

Imaging of femoroacetabular impingement-current concepts

PubMed Central

Albers, Christoph E.; Wambeek, Nicholas; Hanke, Markus S.; Schmaranzer, Florian; Prosser, Gareth H.; Yates, Piers J.

2016-01-01

Following the recognition of femoroacetabular impingement (FAI) as a clinical entity, diagnostic tools have continuously evolved. While the diagnosis of FAI is primarily made based on the patients’ history and clinical examination, imaging of FAI is indispensable. Routine diagnostic work-up consists of a set of plain radiographs, magnetic resonance imaging (MRI) and MR-arthrography. Recent advances in MRI technology include biochemically sensitive sequences bearing the potential to detect degenerative changes of the hip joint at an early stage prior to their appearance on conventional imaging modalities. Computed tomography may serve as an adjunct. Advantages of CT include superior bone to soft tissue contrast, making CT applicable for image-guiding software tools that allow evaluation of the underlying dynamic mechanisms causing FAI. This article provides a summary of current concepts of imaging in FAI and a review of the literature on recent advances, and their application to clinical practice. PMID:29632685

Early prosthetic aortic valve infection identified with the use of positron emission tomography in a patient with lead endocarditis.

PubMed

Amraoui, Sana; Tlili, Ghoufrane; Sohal, Manav; Bordenave, Laurence; Bordachar, Pierre

2016-12-01

18-Fluorodeoxyglucose positron emission tomography/computerized tomography (FDG PET/CT) scanning has recently been proposed as a diagnostic tool for lead endocarditis (LE). FDG PET/CT might be also useful to localize associated septic emboli in patients with LE. We report an interesting case of a LE patient with a prosthetic aortic valve in whom a trans-esophageal echocardiogram did not show associated aortic endocarditis. FDG PET/CT revealed prosthetic aortic valve infection. A second TEE performed 2 weeks after identified aortic vegetation. A longer duration of antimicrobial therapy with serial follow-up echocardiography was initiated. There was also increased uptake in the sigmoid colon, corresponding to focal polyps resected during a colonoscopy. FDG PET/CT scanning seems to be highly sensitive for prosthetic aortic valve endocarditis diagnosis. This promising diagnostic tool may be beneficial in LE patients, by identifying septic emboli and potential sites of pathogen entry.

Evaluation of FTIR spectroscopy as diagnostic tool for colorectal cancer using spectral analysis

NASA Astrophysics Data System (ADS)

Dong, Liu; Sun, Xuejun; Chao, Zhang; Zhang, Shiyun; Zheng, Jianbao; Gurung, Rajendra; Du, Junkai; Shi, Jingsen; Xu, Yizhuang; Zhang, Yuanfu; Wu, Jinguang

2014-03-01

The aim of this study is to confirm FTIR spectroscopy as a diagnostic tool for colorectal cancer. 180 freshly removed colorectal samples were collected from 90 patients for spectrum analysis. The ratios of spectral intensity and relative intensity (/I1460) were calculated. Principal component analysis (PCA) and Fisher's discriminant analysis (FDA) were applied to distinguish the malignant from normal. The FTIR parameters of colorectal cancer and normal tissues were distinguished due to the contents or configurations of nucleic acids, proteins, lipids and carbohydrates. Related to nitrogen containing, water, protein and nucleic acid were increased significantly in the malignant group. Six parameters were selected as independent factors to perform discriminant functions. The sensitivity for FTIR in diagnosing colorectal cancer was 96.6% by discriminant analysis. Our study demonstrates that FTIR can be a useful technique for detection of colorectal cancer and may be applied in clinical colorectal cancer diagnosis.

Whole-body multislice computed tomography as the primary and sole diagnostic tool in patients with blunt trauma: searching for its appropriate indication.

PubMed

Wurmb, Thomas Erik; Frühwald, Peter; Hopfner, Wittiko; Roewer, Norbert; Brederlau, Jörg

2007-11-01

In our hospital, whole-body multislice computed tomography is used as the primary diagnostic tool in patients with suspected multiple trauma. A triage rule is used for its indication. We have retrospectively analyzed data of sedated, intubated and ventilated patients consecutively admitted to our trauma center to assess whether the triage rule can help identify patients with severe trauma (injury severity score > or = 16). We have found that overtriage (injury severity score < 16) occurs in 30%, and undertriage occurs in 6% of patients. Although we have found the triage rule to be highly sensitive, this results in a high rate of overtriage. Until we know more about the most relevant and independent predictive factors, sole reliance upon multislice computed tomography in triaging suspected polytrauma victims will imply the risk to overscan many patients.

Incidence of vertebral hemangioma on spinal magnetic resonance imaging in Northern Iran.

PubMed

Barzin, M; Maleki, I

2009-03-15

The incidence of vertebral hemangiomas as the most common benign spinal neoplasms has been differently reported from 10 to 27% based on autopsy series, plain X-rays and MRI reviews. In this study, we reviewed consecutive 782 standard spinal MRI with axial and sagital T1 weighted and T2 weighted images looking for hemangiomas. In this study, the incidence of hemangioma was 26.9%, more common in females (30%) than males (23%), in older age group and in lumbar spine. Most hemangiomas (65%) were less than 10 mm in diameter. Multiple hemangiomas were seen in 33% of cases. The results of this study are similar to another Mediterranean study reported based on MRI findings, but differ from other reports using X-ray or autopsy as diagnostic tool, suggesting the influence of either the race or the sensitivity of the diagnostic tool on the incidence of vertebral hemangioma.

Use of Malachite Green-Loop Mediated Isothermal Amplification for Detection of Plasmodium spp. Parasites

PubMed Central

Lucchi, Naomi W.; Ljolje, Dragan; Silva-Flannery, Luciana; Udhayakumar, Venkatachalam

2016-01-01

Malaria elimination efforts are hampered by the lack of sensitive tools to detect infections with low-level parasitemia, usually below the threshold of standard diagnostic methods, microscopy and rapid diagnostic tests. Isothermal nucleic acid amplification assays such as the loop-mediated isothermal amplification (LAMP), are well suited for field use as they do not require thermal cyclers to run the test. However, the use of specialized equipment, as described by many groups, reduces the versatility of the LAMP technique as a simple tool for use in endemic countries. In this study, the use of the malachite green (MG) dye, as a visual endpoint readout, together with a simple mini heat block was evaluated for the detection of malaria parasites. The assay was performed for 1 hour at 63°C and the results scored by 3 independent human readers. The limit of detection of the assay was determined using well-quantified Plasmodium spp. infected reference samples and its utility in testing clinical samples was determined using 190 pre-treatment specimens submitted for reference diagnosis of imported malaria in the United States. Use of a simplified boil and spin methods of DNA extraction from whole blood and filter paper was also investigated. We demonstrate the accurate and sensitive detection of malaria parasites using this assay with a detection limit ranging between 1–8 parasites/μL, supporting its applicability for the detection of infections with low parasite burden. This assay is compatible with the use of a simple boil and spin sample preparation method from both whole blood and filter papers without a loss of sensitivity. The MG-LAMP assay described here has great potential to extend the reach of molecular tools to settings where they are needed. PMID:26967908

Using microRNA profiling in urine samples to develop a non-invasive test for bladder cancer.

PubMed

Mengual, Lourdes; Lozano, Juan José; Ingelmo-Torres, Mercedes; Gazquez, Cristina; Ribal, María José; Alcaraz, Antonio

2013-12-01

Current standard methods used to detect and monitor bladder urothelial cell carcinoma (UCC) are invasive or have low sensitivity. The incorporation into clinical practice of a non-invasive tool for UCC assessment would enormously improve patients' quality of life and outcome. This study aimed to examine the microRNA (miRNA) expression profiles in urines of UCC patients in order to develop a non-invasive accurate and reliable tool to diagnose and provide information on the aggressiveness of the tumor. We performed a global miRNA expression profiling analysis of the urinary cells from 40 UCC patients and controls using TaqMan Human MicroRNA Array followed by validation of 22 selected potentially diagnostic and prognostic miRNAs in a separate cohort of 277 samples using a miRCURY LNA qPCR system. miRNA-based signatures were developed by multivariate logistic regression analysis and internally cross-validated. In the initial cohort of patients, we identified 40 and 30 aberrantly expressed miRNA in UCC compared with control urines and in high compared with low grade tumors, respectively. Quantification of 22 key miRNAs in an independent cohort resulted in the identification of a six miRNA diagnostic signature with a sensitivity of 84.8% and specificity of 86.5% (AUC = 0.92) and a two miRNA prognostic model with a sensitivity of 84.95% and a specificity of 74.14% (AUC = 0.83). Internal cross-validation analysis confirmed the accuracy rates of both models, reinforcing the strength of our findings. Although the data needs to be externally validated, miRNA analysis in urine appears to be a valuable tool for the non-invasive assessment of UCC. Copyright © 2013 UICC.

Methods Developed by the Tools for Engine Diagnostics Task to Monitor and Predict Rotor Damage in Real Time

NASA Technical Reports Server (NTRS)

Baaklini, George Y.; Smith, Kevin; Raulerson, David; Gyekenyesi, Andrew L.; Sawicki, Jerzy T.; Brasche, Lisa

2003-01-01

Tools for Engine Diagnostics is a major task in the Propulsion System Health Management area of the Single Aircraft Accident Prevention project under NASA s Aviation Safety Program. The major goal of the Aviation Safety Program is to reduce fatal aircraft accidents by 80 percent within 10 years and by 90 percent within 25 years. The goal of the Propulsion System Health Management area is to eliminate propulsion system malfunctions as a primary or contributing factor to the cause of aircraft accidents. The purpose of Tools for Engine Diagnostics, a 2-yr-old task, is to establish and improve tools for engine diagnostics and prognostics that measure the deformation and damage of rotating engine components at the ground level and that perform intermittent or continuous monitoring on the engine wing. In this work, nondestructive-evaluation- (NDE-) based technology is combined with model-dependent disk spin experimental simulation systems, like finite element modeling (FEM) and modal norms, to monitor and predict rotor damage in real time. Fracture mechanics time-dependent fatigue crack growth and damage-mechanics-based life estimation are being developed, and their potential use investigated. In addition, wireless eddy current and advanced acoustics are being developed for on-wing and just-in-time NDE engine inspection to provide deeper access and higher sensitivity to extend on-wing capabilities and improve inspection readiness. In the long run, these methods could establish a base for prognostic sensing while an engine is running, without any overt actions, like inspections. This damage-detection strategy includes experimentally acquired vibration-, eddy-current- and capacitance-based displacement measurements and analytically computed FEM-, modal norms-, and conventional rotordynamics-based models of well-defined damages and critical mass imbalances in rotating disks and rotors.

Potential of mid-infrared spectroscopy as a non-invasive diagnostic test in urine for endometrial or ovarian cancer.

PubMed

Paraskevaidi, Maria; Morais, Camilo L M; Lima, Kássio M G; Ashton, Katherine M; Stringfellow, Helen F; Martin-Hirsch, Pierre L; Martin, Francis L

2018-06-07

The current lack of an accurate, cost-effective and non-invasive test that would allow for screening and diagnosis of gynaecological carcinomas, such as endometrial and ovarian cancer, signals the necessity for alternative approaches. The potential of spectroscopic techniques in disease investigation and diagnosis has been previously demonstrated. Here, we used attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy to analyse urine samples from women with endometrial (n = 10) and ovarian cancer (n = 10), as well as from healthy individuals (n = 10). After applying multivariate analysis and classification algorithms, biomarkers of disease were pointed out and high levels of accuracy were achieved for both endometrial (95% sensitivity, 100% specificity; accuracy: 95%) and ovarian cancer (100% sensitivity, 96.3% specificity; accuracy 100%). The efficacy of this approach, in combination with the non-invasive method for urine collection, suggest a potential diagnostic tool for endometrial and ovarian cancers.

INCLEN Diagnostic Tool for Autism Spectrum Disorder (INDT-ASD): development and validation.

PubMed

Juneja, Monica; Mishra, Devendra; Russell, Paul S S; Gulati, Sheffali; Deshmukh, Vaishali; Tudu, Poma; Sagar, Rajesh; Silberberg, Donald; Bhutani, Vinod K; Pinto, Jennifer M; Durkin, Maureen; Pandey, Ravindra M; Nair, M K C; Arora, Narendra K

2014-05-01

To develop and validate INCLEN Diagnostic Tool for Autism Spectrum Disorder (INDT-ASD). Diagnostic test evaluation by cross sectional design. Four tertiary pediatric neurology centers in Delhi and Thiruvanthapuram, India. Children aged 2-9 years were enrolled in the study. INDT-ASD and Childhood Autism Rating Scale (CARS) were administered in a randomly decided sequence by trained psychologist, followed by an expert evaluation by DSM-IV TR diagnostic criteria (gold standard). Psychometric parameters of diagnostic accuracy, validity (construct, criterion and convergent) and internal consistency. 154 children (110 boys, mean age 64.2 mo) were enrolled. The overall diagnostic accuracy (AUC=0.97, 95% CI 0.93, 0.99; P<0.001) and validity (sensitivity 98%, specificity 95%, positive predictive value 91%, negative predictive value 99%) of INDT-ASD for Autism spectrum disorder were high, taking expert diagnosis using DSM-IV-TR as gold standard. The concordance rate between the INDT-ASD and expert diagnosis for 'ASD group' was 82.52% [Cohen's k=0.89; 95% CI (0.82, 0.97); P=0.001]. The internal consistency of INDT-ASD was 0.96. The convergent validity with CARS (r = 0.73, P= 0.001) and divergent validity with Binet-Kamat Test of intelligence (r = -0.37; P=0.004) were significantly high. INDT-ASD has a 4-factor structure explaining 85.3% of the variance. INDT-ASD has high diagnostic accuracy, adequate content validity, good internal consistency high criterion validity and high to moderate convergent validity and 4-factor construct validity for diagnosis of Autistm spectrum disorder.

Prehospital lung ultrasound for the diagnosis of cardiogenic pulmonary oedema: a pilot study.

PubMed

Laursen, Christian B; Hänselmann, Anja; Posth, Stefan; Mikkelsen, Søren; Videbæk, Lars; Berg, Henrik

2016-08-02

An improved prehospital diagnostic accuracy of cardiogenic pulmonary oedema could potentially improve initial treatment, triage, and outcome. A pilot study was conducted to assess the feasibility, time-use, and diagnostic accuracy of prehospital lung ultrasound (PLUS) for the diagnosis of cardiogenic pulmonary oedema. A prospective observational study was conducted in a prehospital setting. Patients were included if the physician based prehospital mobile emergency care unit was activated and one or more of the following two were present: respiratory rate >30/min., oxygen saturation <90 %. Exclusion criteria were: age <18 years, permanent mental disability or PLUS causing a delay in life-saving treatment or transportation. Following clinical assessment PLUS was performed and presence or absence of interstitial syndrome was registered. Audit by three physicians using predefined diagnostic criteria for cardiogenic pulmonary oedema was used as gold standard. A total of 40 patients were included in the study. Feasibility of PLUS was 100 % and median time used was 3 min. The gold standard diagnosed 18 (45.0 %) patients with cardiogenic pulmonary oedema. The diagnostic accuracy of PLUS for the diagnosis of cardiogenic pulmonary oedema was: sensitivity 94.4 % (95 % confidence interval (CI) 72.7-99.9 %), specificity 77.3 % (95 % CI 54.6-92.2 %), positive predictive value 77.3 % (95 % CI 54.6-92.2 %), negative predictive value 94.4 % (95 % CI 72.7-99.9 %). The sensitivity of PLUS is high, making it a potential tool for ruling-out cardiogenic pulmonary. The observed specificity was lower than what has been described in previous studies. Performed, as part of a physician based prehospital emergency service, PLUS seems fast and highly feasible in patients with respiratory failure. Due to its diagnostic accuracy, PLUS may have potential as a prehospital tool, especially to rule out cardiogenic pulmonary oedema.

The Microbial Detection Array Combined with Random Phi29-Amplification Used as a Diagnostic Tool for Virus Detection in Clinical Samples

PubMed Central

Erlandsson, Lena; Rosenstierne, Maiken W.; McLoughlin, Kevin; Jaing, Crystal; Fomsgaard, Anders

2011-01-01

A common technique used for sensitive and specific diagnostic virus detection in clinical samples is PCR that can identify one or several viruses in one assay. However, a diagnostic microarray containing probes for all human pathogens could replace hundreds of individual PCR-reactions and remove the need for a clear clinical hypothesis regarding a suspected pathogen. We have established such a diagnostic platform for random amplification and subsequent microarray identification of viral pathogens in clinical samples. We show that Phi29 polymerase-amplification of a diverse set of clinical samples generates enough viral material for successful identification by the Microbial Detection Array, demonstrating the potential of the microarray technique for broad-spectrum pathogen detection. We conclude that this method detects both DNA and RNA virus, present in the same sample, as well as differentiates between different virus subtypes. We propose this assay for diagnostic analysis of viruses in clinical samples. PMID:21853040

[Laboratory diagnostics of urogenital clamidiosis].

PubMed

Churakov, A A; Kulichenko, A N; Kzakova, E S; Serebrianik, N E; Suvorov, A P; Kutyrev, V V; Glybochko, P V

2005-02-01

Laboratory diagnostic tools of urogenital clamidiosis--PCR, ELISA (IgG and IgM) and direct immunofluorescence (DIF)--were comparatively analyzed. The positive PCR result was checked by another PCR test with a different primer; 5 false positive responses were registered (specificity 99.6%). As against PCR, the sensitivity of ELISA made 53%, its specificity -75.5%, the diagnostic value of positive result -58%, the diagnostic value of negative result -71.6% and the diagnostics accuracy -66.7%. The respective DIF parameters were as follows: 36%, 90%, 81.5%, 54.2% and 60.9%. A high rate of detection (above 90%) of the conditionally pathogenic microflora associated with Chlamydia trachomatis (above 110 microbe cells/ml) was pointed out. Hardnerelli and ureaplasms were more often found in female smears, staphylococci and enterococci--in male sperm. It is underlined as important to hold complex examinations for Chlamidia (PCR, ELISA and DIC as an additional test) combined with bacteriological quantification of the conditionally pathogenic microflora and determination of its resistance to antibiotics.

Loop mediated isothermal amplification: An innovative gene amplification technique for animal diseases.

PubMed

Sahoo, Pravas Ranjan; Sethy, Kamadev; Mohapatra, Swagat; Panda, Debasis

2016-05-01

India being a developing country mainly depends on livestock sector for its economy. However, nowadays, there is emergence and reemergence of more transboundary animal diseases. The existing diagnostic techniques are not so quick and with less specificity. To reduce the economy loss, there should be a development of rapid, reliable, robust diagnostic technique, which can work with high degree of sensitivity and specificity. Loop mediated isothermal amplification assay is a rapid gene amplification technique that amplifies nucleic acid under an isothermal condition with a set of designed primers spanning eight distinct sequences of the target. This assay can be used as an emerging powerful, innovative gene amplification diagnostic tool against various pathogens of livestock diseases. This review is to highlight the basic concept and methodology of this assay in livestock disease.

Evaluation of a focussed protocol for hand-held echocardiography and computer-assisted auscultation in detecting latent rheumatic heart disease in scholars.

PubMed

Zühlke, Liesl J; Engel, Mark E; Nkepu, Simpiwe; Mayosi, Bongani M

2016-08-01

Introduction Echocardiography is the diagnostic test of choice for latent rheumatic heart disease. The utility of echocardiography for large-scale screening is limited by high cost, complex diagnostic protocols, and time to acquire multiple images. We evaluated the performance of a brief hand-held echocardiography protocol and computer-assisted auscultation in detecting latent rheumatic heart disease with or without pathological murmur. A total of 27 asymptomatic patients with latent rheumatic heart disease based on the World Heart Federation criteria and 66 healthy controls were examined by standard cardiac auscultation to detect pathological murmur. Hand-held echocardiography using a focussed protocol that utilises one view - that is, the parasternal long-axis view - and one measurement - that is, mitral regurgitant jet - and a computer-assisted auscultation utilising an automated decision tool were performed on all patients. The sensitivity and specificity of computer-assisted auscultation in latent rheumatic heart disease were 4% (95% CI 1.0-20.4%) and 93.7% (95% CI 84.5-98.3%), respectively. The sensitivity and specificity of the focussed hand-held echocardiography protocol for definite rheumatic heart disease were 92.3% (95% CI 63.9-99.8%) and 100%, respectively. The test reliability of hand-held echocardiography was 98.7% for definite and 94.7% for borderline disease, and the adjusted diagnostic odds ratios were 1041 and 263.9 for definite and borderline disease, respectively. Computer-assisted auscultation has extremely low sensitivity but high specificity for pathological murmur in latent rheumatic heart disease. Focussed hand-held echocardiography has fair sensitivity but high specificity and diagnostic utility for definite or borderline rheumatic heart disease in asymptomatic patients.

Sensitivity, Specificity, Predictive Values, and Accuracy of Three Diagnostic Tests to Predict Inferior Alveolar Nerve Blockade Failure in Symptomatic Irreversible Pulpitis

PubMed Central

Rodríguez-Wong, Laura; Noguera-González, Danny; Esparza-Villalpando, Vicente; Montero-Aguilar, Mauricio

2017-01-01

Introduction The inferior alveolar nerve block (IANB) is the most common anesthetic technique used on mandibular teeth during root canal treatment. Its success in the presence of preoperative inflammation is still controversial. The aim of this study was to evaluate the sensitivity, specificity, predictive values, and accuracy of three diagnostic tests used to predict IANB failure in symptomatic irreversible pulpitis (SIP). Methodology A cross-sectional study was carried out on the mandibular molars of 53 patients with SIP. All patients received a single cartridge of mepivacaine 2% with 1 : 100000 epinephrine using the IANB technique. Three diagnostic clinical tests were performed to detect anesthetic failure. Anesthetic failure was defined as a positive painful response to any of the three tests. Sensitivity, specificity, predictive values, accuracy, and ROC curves were calculated and compared and significant differences were analyzed. Results IANB failure was determined in 71.7% of the patients. The sensitivity scores for the three tests (lip numbness, the cold stimuli test, and responsiveness during endodontic access) were 0.03, 0.35, and 0.55, respectively, and the specificity score was determined as 1 for all of the tests. Clinically, none of the evaluated tests demonstrated a high enough accuracy (0.30, 0.53, and 0.68 for lip numbness, the cold stimuli test, and responsiveness during endodontic access, resp.). A comparison of the areas under the curve in the ROC analyses showed statistically significant differences between the three tests (p < 0.05). Conclusion None of the analyzed tests demonstrated a high enough accuracy to be considered a reliable diagnostic tool for the prediction of anesthetic failure. PMID:28694714

Accuracy of early detection of colorectal tumours by stool methylation markers: A meta-analysis

PubMed Central

Zhang, Hu; Qi, Jian; Wu, Ya-Qiong; Zhang, Ping; Jiang, Jun; Wang, Qi-Xian; Zhu, You-Qing

2014-01-01

AIM: To evaluate the accuracy of methylation of genes in stool samples for diagnosing colorectal tumours. METHODS: Electronic databases including PubMed, Web of Science, Chinese Journals Full-Text Database and Wanfang Journals Full-Text Database were searched to find relevant original articles about methylated genes to be used in diagnosing colorectal tumours. A quality assessment of diagnostic accuracy studies tool (QADAS) was used to evaluate the quality of the included articles, and the Meta-disc 1.4 and SPSS 13.0 software programs were used for data analysis. RESULTS: Thirty-seven articles met the inclusion criteria, and 4484 patients were included. The sensitivity and specificity for the detection of colorectal cancer (CRC) were 73% (95%CI: 71%-75%) and 92% (95%CI: 90%-93%), respectively. For adenoma, the sensitivity and specificity were 51% (95%CI: 47%-54%) and 92% (95%CI: 90%-93%), respectively. Pooled diagnostic performance of SFRP2 methylation for CRC provided the following results: the sensitivity was 79% (95%CI: 75%-82%), the specificity was 93% (95%CI: 90%-96%), the diagnostic OR was 47.57 (95%CI: 20.08-112.72), the area under the curve was 0.9565. Additionally, the results of accuracy of SFRP2 methylation for detecting colorectal adenomas were as follows: sensitivity was 43% (95%CI: 38%-49%), specificity was 94% (95%CI: 91%-97%), the diagnostic OR was 11.06 (95%CI: 5.77-21.18), and the area under the curve was 0.9563. CONCLUSION: Stool-based DNA testing may be useful for noninvasively diagnosing colorectal tumours and SFRP2 methylation is a promising marker that has great potential in early CRC diagnosis. PMID:25320544

The diagnostic accuracy of screening questionnaires for the identification of adults with epilepsy: a systematic review.

PubMed

Keezer, Mark R; Bouma, Hanni K; Wolfson, Christina

2014-11-01

To describe the diagnostic accuracy of screening questionnaires to identify epilepsy in adults, we performed a systematic review of diagnostic studies that assessed the sensitivity and specificity of such screening questionnaires as compared to a physician's clinical assessment. We searched Ovid MEDLINE (1946 to present) and Ovid EMBASE (1947 to present) for studies that estimated the sensitivity and specificity of nonphysician administered screening questionnaires for adults with epilepsy. Both telephone and in-person administered questionnaires were included, whether applied to population or hospital/clinic-based cohorts. The risk of bias was assessed using the Quality Assessment of Diagnostic Studies-2 (QUADAS-2) tool. Our initial search strategy resulted in 917 records. We found nine studies eligible for inclusion. The estimated sensitivity and specificity of the questionnaires used to identify persons with a lifetime history of epilepsy ranged from 81.5% to 100% and 65.6% to 99.2%, respectively. The sensitivity and specificity of these questionnaires in identifying persons with active epilepsy ranged from 48.6% to 100% and 73.9% to 99.9%, respectively. Overall we found a high risk of bias in patient selection and study flow in the majority of studies. We identified nine validation studies of epilepsy screening questionnaires, summarized their study characteristics, presented their results, and performed a rigorous quality assessment. This review serves as a basis for future studies by providing a systematic review of existing work. Future research addressing previous limitations will ultimately allow us to more accurately estimate the burden and risk of epilepsy in the general population. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.

Rapid and sensitive detection of Yersinia pestis using amplification of plague diagnostic bacteriophages monitored by real-time PCR.

PubMed

Sergueev, Kirill V; He, Yunxiu; Borschel, Richard H; Nikolich, Mikeljon P; Filippov, Andrey A

2010-06-28

Yersinia pestis, the agent of plague, has caused many millions of human deaths and still poses a serious threat to global public health. Timely and reliable detection of such a dangerous pathogen is of critical importance. Lysis by specific bacteriophages remains an essential method of Y. pestis detection and plague diagnostics. The objective of this work was to develop an alternative to conventional phage lysis tests--a rapid and highly sensitive method of indirect detection of live Y. pestis cells based on quantitative real-time PCR (qPCR) monitoring of amplification of reporter Y. pestis-specific bacteriophages. Plague diagnostic phages phiA1122 and L-413C were shown to be highly effective diagnostic tools for the detection and identification of Y. pestis by using qPCR with primers specific for phage DNA. The template DNA extraction step that usually precedes qPCR was omitted. phiA1122-specific qPCR enabled the detection of an initial bacterial concentration of 10(3) CFU/ml (equivalent to as few as one Y. pestis cell per 1-microl sample) in four hours. L-413C-mediated detection of Y. pestis was less sensitive (up to 100 bacteria per sample) but more specific, and thus we propose parallel qPCR for the two phages as a rapid and reliable method of Y. pestis identification. Importantly, phiA1122 propagated in simulated clinical blood specimens containing EDTA and its titer rise was detected by both a standard plating test and qPCR. Thus, we developed a novel assay for detection and identification of Y. pestis using amplification of specific phages monitored by qPCR. The method is simple, rapid, highly sensitive, and specific and allows the detection of only live bacteria.

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.

Accuracy of early detection of colorectal tumours by stool methylation markers: a meta-analysis.

PubMed

Zhang, Hu; Qi, Jian; Wu, Ya-Qiong; Zhang, Ping; Jiang, Jun; Wang, Qi-Xian; Zhu, You-Qing

2014-10-14

To evaluate the accuracy of methylation of genes in stool samples for diagnosing colorectal tumours. Electronic databases including PubMed, Web of Science, Chinese Journals Full-Text Database and Wanfang Journals Full-Text Database were searched to find relevant original articles about methylated genes to be used in diagnosing colorectal tumours. A quality assessment of diagnostic accuracy studies tool (QADAS) was used to evaluate the quality of the included articles, and the Meta-disc 1.4 and SPSS 13.0 software programs were used for data analysis. Thirty-seven articles met the inclusion criteria, and 4484 patients were included. The sensitivity and specificity for the detection of colorectal cancer (CRC) were 73% (95%CI: 71%-75%) and 92% (95%CI: 90%-93%), respectively. For adenoma, the sensitivity and specificity were 51% (95%CI: 47%-54%) and 92% (95%CI: 90%-93%), respectively. Pooled diagnostic performance of SFRP2 methylation for CRC provided the following results: the sensitivity was 79% (95%CI: 75%-82%), the specificity was 93% (95%CI: 90%-96%), the diagnostic OR was 47.57 (95%CI: 20.08-112.72), the area under the curve was 0.9565. Additionally, the results of accuracy of SFRP2 methylation for detecting colorectal adenomas were as follows: sensitivity was 43% (95%CI: 38%-49%), specificity was 94% (95%CI: 91%-97%), the diagnostic OR was 11.06 (95%CI: 5.77-21.18), and the area under the curve was 0.9563. Stool-based DNA testing may be useful for noninvasively diagnosing colorectal tumours and SFRP2 methylation is a promising marker that has great potential in early CRC diagnosis.

Predictive Accuracy of Sweep Frequency Impedance Technology in Identifying Conductive Conditions in Newborns.

PubMed

Aithal, Venkatesh; Kei, Joseph; Driscoll, Carlie; Murakoshi, Michio; Wada, Hiroshi

2018-02-01

Diagnosing conductive conditions in newborns is challenging for both audiologists and otolaryngologists. Although high-frequency tympanometry (HFT), acoustic stapedial reflex tests, and wideband absorbance measures are useful diagnostic tools, there is performance measure variability in their detection of middle ear conditions. Additional diagnostic sensitivity and specificity measures gained through new technology such as sweep frequency impedance (SFI) measures may assist in the diagnosis of middle ear dysfunction in newborns. The purpose of this study was to determine the test performance of SFI to predict the status of the outer and middle ear in newborns against commonly used reference standards. Automated auditory brainstem response (AABR), HFT (1000 Hz), transient evoked otoacoustic emission (TEOAE), distortion product otoacoustic emission (DPOAE), and SFI tests were administered to the study sample. A total of 188 neonates (98 males and 90 females) with a mean gestational age of 39.4 weeks were included in the sample. Mean age at the time of testing was 44.4 hr. Diagnostic accuracy of SFI was assessed in terms of its ability to identify conductive conditions in neonates when compared with nine different reference standards (including four single tests [AABR, HFT, TEOAE, and DPOAE] and five test batteries [HFT + DPOAE, HFT + TEOAE, DPOAE + TEOAE, DPOAE + AABR, and TEOAE + AABR]), using receiver operating characteristic (ROC) analysis and traditional test performance measures such as sensitivity and specificity. The test performance of SFI against the test battery reference standard of HFT + DPOAE and single reference standard of HFT was high with an area under the ROC curve (AROC) of 0.87 and 0.82, respectively. Although the HFT + DPOAE test battery reference standard performed better than the HFT reference standard in predicting middle ear conductive conditions in neonates, the difference in AROC was not significant. Further analysis revealed that the highest sensitivity and specificity for SFI (86% and 88%, respectively) was obtained when compared with the reference standard of HFT + DPOAE. Among the four single reference standards, SFI had the highest sensitivity and specificity (76% and 88%, respectively) when compared against the HFT reference standard. The high test performance of SFI against the HFT and HFT + DPOAE reference standards indicates that the SFI measure has appropriate diagnostic accuracy in detection of conductive conditions in newborns. Hence, the SFI test could be used as adjunct tool to identify conductive conditions in universal newborn hearing screening programs, and can also be used in diagnostic follow-up assessments. American Academy of Audiology

Diagnostic performance characteristics of a rapid field test for anthrax in cattle.

PubMed

Muller, Janine; Gwozdz, Jacek; Hodgeman, Rachel; Ainsworth, Catherine; Kluver, Patrick; Czarnecki, Jill; Warner, Simone; Fegan, Mark

2015-07-01

Although diagnosis of anthrax can be made in the field with a peripheral blood smear, and in the laboratory with bacterial culture or molecular based tests, these tests require either considerable experience or specialised equipment. Here we report on the evaluation of the diagnostic sensitivity and specificity of a simple and rapid in-field diagnostic test for anthrax, the anthrax immunochromatographic test (AICT). The AICT detects the protective antigen (PA) component of the anthrax toxin present within the blood of an animal that has died from anthrax. The test provides a result in 15min and offers the advantage of avoiding the necessity for on-site necropsy and subsequent occupational risks and environmental contamination. The specificity of the test was determined by testing samples taken from 622 animals, not infected with Bacillus anthracis. Diagnostic sensitivity was estimated on samples taken from 58 animals, naturally infected with B. anthracis collected over a 10-year period. All samples used to estimate the diagnostic sensitivity and specificity of the AICT were also tested using the gold standard of bacterial culture. The diagnostic specificity of the test was estimated to be 100% (99.4-100%; 95% CI) and the diagnostic sensitivity was estimated to be 93.1% (83.3-98.1%; 95% CI) (Clopper-Pearson method). Four samples produced false negative AICT results. These were among 9 samples, all of which tested positive for B. anthracis by culture, where there was a time delay between collection and testing of >48h and/or the samples were collected from animals that were >48h post-mortem. A statistically significant difference (P<0.001; Fishers exact test) was found between the ability of the AICT to detect PA in samples from culture positive animals <48h post-mortem, 49 of 49, Se=100% (92.8-100%; 95% CI) compared with samples tested >48h post-mortem 5 of 9 Se=56% (21-86.3%; 95% CI) (Clopper-Pearson method). Based upon these results a post hoc cut-off for use of the AICT of 48h post-mortem was applied, Se=100% (92.8-100%; 95% CI) and Sp=100% (99.4-100%; 95% CI). The high diagnostic sensitivity and specificity and the simplicity of the AICT enables it to be used for active surveillance in areas with a history of anthrax, or used as a preliminary tool in investigating sudden, unexplained death in cattle. Copyright © 2015 Elsevier B.V. All rights reserved.

Bench-to-bedside review: Rapid molecular diagnostics for bloodstream infection - a new frontier?

PubMed Central

2012-01-01

Among critically ill patients, the diagnosis of bloodstream infection poses a major challenge. Current standard bacterial identification based on blood culture platforms is intrinsically time-consuming and slow. The continuous evolvement of molecular techniques has the potential of providing a faster, more sensitive and direct identification of causative pathogens without prior need for cultivation. This may ultimately impact clinical decision-making and antimicrobial treatment. This review summarises the currently available technologies, their strengths and limitations and the obstacles that have to be overcome in order to develop a satisfactory bedside point-of-care diagnostic tool for detection of bloodstream infection. PMID:22647543

Diagnosing clean margins through Raman spectroscopy in human and animal mammary tumour surgery: a short review

PubMed Central

Birtoiu, I. A.; Rizea, C.; Togoe, D.; Munteanu, R. M.; Micsa, C.; Rusu, M. I.; Tautan, M.; Braic, L.; Scoicaru, L. O.; Parau, A.; Becherescu-Barbu, N. D.; Udrea, M. V.; Tonetto, A.; Notonier, R.

2016-01-01

Breast cancer frequency in human and other mammal female populations has worryingly increased lately. The acute necessity for taxonomy of the aetiological factors along with seeking for new diagnostic tools and therapy procedures aimed at reducing mortality have yielded in an intense research effort worldwide. Surgery is a regular method to counteract extensive development of breast cancer and prevent metastases provided that negative surgical margins are achieved. This highly technical challenge requires fast, extremely sensitive and selective discrimination between malignant and benign tissues even down to molecular level. The particular advantages of Raman spectroscopy, such as high chemical specificity, and the ability to measure raw samples and optical responses in the visible or near-infrared spectral range, have recently recommended it as a means with elevated potential in precise diagnostic in oncology surgery. This review spans mainly the latter 10 years of exceptional efforts of scientists implementing Raman spectroscopy as a nearly real-time diagnostic tool for clean margins assessment in mastectomy and lumpectomy. Although greatly contributing to medical discoveries for the wealth of humanity, animals as patients have benefitted less from advances in surgery diagnostic using Raman spectroscopy. This work also dedicates a few lines to applications of surface enhanced Raman spectroscopy in veterinary oncological surgery. PMID:27920899

3D-CAM: Derivation and Validation of a 3-Minute Diagnostic Interview for CAM-defined Delirium

PubMed Central

Marcantonio, Edward R.; Ngo, Long H.; O’Connor, Margaret; Jones, Richard N.; Crane, Paul K.; Metzger, Eran D.; Inouye, Sharon K.

2015-01-01

Background Delirium is common, morbid, and costly, yet remains often unrecognized in most clinical settings. The Confusion Assessment Method (CAM) is the most widely used diagnostic algorithm, and operationalizing its features would represent a substantial advance for clinical care. Objective To derive the 3D-CAM, a new 3-minute diagnostic assessment for CAM-defined delirium, and to validate it against a clinical reference standard. Design Diagnostic test study Setting 4 general medicine units in an academic medical center Participants 201 inpatients aged ≥ 75 years old Measurements We identified 20 items that best operationalized the 4 CAM diagnostic features to create the 3D-CAM. For prospective validation, 3D-CAM assessments were administered by trained research assistants. Independently, clinicians performed an extensive assessment that included patient interviews, family interviews, and review of the medical record. These data were considered by an expert panel to determine the presence or absence of delirium and dementia (reference standard). We compared the 3D-CAM delirium determination to the reference standard in all patients and in subgroups with and without dementia. Results The 201 participants in the prospective validation study had mean age (SD) of 84 (5.5) years, and 27% had dementia. The expert panel identified delirium in 21%. Median administration time for 3D-CAM was 3 minutes (inter-quartile range: 2–5 minutes). The sensitivity [95% CI] of 3D-CAM was 95% [84%, 99%] and the specificity was 94% [90%, 97%]. The 3D-CAM performed well in patients both with dementia (sensitivity=96% [82%, 100%], specificity=86% [67%, 96%]) and without dementia (sensitivity=93% [66%, 100%], specificity=96% [91%,99%]). Limitations Limited to single center, cross-sectional, and medicine patients only Conclusion The 3D-CAM operationalizes the CAM algorithm using a 3-minute structured assessment with high sensitivity and specificity relative to a reference standard and could be an important tool for improving recognition of delirium. PMID:25329203

Performance of rapid diagnostic test, blood-film microscopy and PCR for the diagnosis of malaria infection among febrile children from Korogwe District, Tanzania.

PubMed

Mahende, Coline; Ngasala, Billy; Lusingu, John; Yong, Tai-Soon; Lushino, Paminus; Lemnge, Martha; Mmbando, Bruno; Premji, Zul

2016-07-26

Rapid diagnostic tests (RDT) and light microscopy are still recommended for diagnosis to guide the clinical management of malaria despite difficult challenges in rural settings. The performance of these tests may be affected by several factors, including malaria prevalence and intensity of transmission. The study evaluated the diagnostic performance of malaria RDT, light microscopy and polymerase chain reaction (PCR) in detecting malaria infections among febrile children at outpatient clinic in Korogwe District, northeastern Tanzania. The study enrolled children aged 2-59 months with fever and/or history of fever in the previous 48 h attending outpatient clinics. Blood samples were collected for identification of Plasmodium falciparum infection using histidine-rich-protein-2 (HRP-2)-based malaria RDT, light microscopy and conventional PCR. A total of 867 febrile patients were enrolled into the study. Malaria-positive samples were 85/867 (9.8 %, 95 % CI, 7.9-12.0 %) by RDT, 72/867 (8.3 %, 95 % CI, 6.5-10.1 %) by microscopy and 79/677 (11.7 %, 95 % CI, 9.3-14.3 %) by PCR. The performance of malaria RDT compared with microscopy results had sensitivity and positive predictive value (PPV) of 88.9 % (95 % CI, 79.3-95.1 %) and 75.3 % (95 % CI, 64.8-84.0 %), respectively. Confirmation of P. falciparum infection with PCR analysis provided lower sensitivity and PPV of 88.6 % (95 % CI, 79.5-94.7 %) and 84.3 % (95 % CI, 74.7-91.4 %) for RDT compared to microscopy. Diagnosis of malaria infection is still a challenge due to variation in results among diagnostic methods. HRP-2 malaria RDT and microscopy were less sensitive than PCR. Diagnostic tools with high sensitivity are required in areas of low malaria transmission.

Transbronchial Lung Cryobiopsy and Video-assisted Thoracoscopic Lung Biopsy in the Diagnosis of Diffuse Parenchymal Lung Disease. A Meta-analysis of Diagnostic Test Accuracy.

PubMed

Iftikhar, Imran H; Alghothani, Lana; Sardi, Alejandro; Berkowitz, David; Musani, Ali I

2017-07-01

Transbronchial lung cryobiopsy is increasingly being used for the assessment of diffuse parenchymal lung diseases. Several studies have shown larger biopsy samples and higher yields compared with conventional transbronchial biopsies. However, the higher risk of bleeding and other complications has raised concerns for widespread use of this modality. To study the diagnostic accuracy and safety profile of transbronchial lung cryobiopsy and compare with video-assisted thoracoscopic surgery (VATS) by reviewing available evidence from the literature. Medline and PubMed were searched from inception until December 2016. Data on diagnostic performance were abstracted by constructing two-by-two contingency tables for each study. Data on a priori selected safety outcomes were collected. Risk of bias was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool. Random effects meta-analyses were performed to obtain summary estimates of the diagnostic accuracy. The pooled diagnostic yield, pooled sensitivity, and pooled specificity of transbronchial lung cryobiopsy were 83.7% (76.9-88.8%), 87% (85-89%), and 57% (40-73%), respectively. The pooled diagnostic yield, pooled sensitivity, and pooled specificity of VATS were 92.7% (87.6-95.8%), 91.0% (89-92%), and 58% (31-81%), respectively. The incidence of grade 2 (moderate to severe) endobronchial bleeding after transbronchial lung cryobiopsy and of post-procedural pneumothorax was 4.9% (2.2-10.7%) and 9.5% (5.9-14.9%), respectively. Although the diagnostic test accuracy measures of transbronchial lung cryobiopsy lag behind those of VATS, with an acceptable safety profile and potential cost savings, the former could be considered as an alternative in the evaluation of patients with diffuse parenchymal lung diseases.

Dual-hologram shearing interference technique with regulated sensitivity

NASA Astrophysics Data System (ADS)

Toker, Gregory R.; Levin, Daniel

1998-06-01

A novel optical diagnostic technique,namely, a dual hologram shearing interferometry with regulated sensitivity, is proposed for visualization and measuring the density gradients of compressible flows in wind tunnels. It has advantages over conventional shearing interferometry in both accuracy and sensitivity. The method is especially useful for strong turbulent or unsteady regions of the flows including shock flows. The interferometer proved to be insensitive to mechanical vibrations and allowed to record holograms during the noisy wind tunnel run. The proposed approach was demonstrated by its application to a supersonic flow over spherically blunted and sharp nose cone/cylinder models. It is believed that the technique will become an effective tool for receiving optical data in many flow facilities.

Dual-hologram shearing interferometry with regulated sensitivity

NASA Astrophysics Data System (ADS)

Toker, Gregory R.; Levin, Daniel

1998-07-01

A novel optical diagnostic technique, namely, a dual hologram shearing interferometry with regulated sensitivity, is proposed for visualization and measuring the density gradients of compressible flows in wind tunnels. It has advantages over conventional shearing interferometry in both accuracy and sensitivity. The method is especially useful for strong turbulent or unsteady regions of the flows including shock flows. The interferometer proved to be insensitive to mechanical vibrations and allowed to record holograms during the noisy wind tunnel run. The proposed approach was demonstrated by its application to a supersonic flow over spherically blunted and sharp nose cone/cylinder models. It is believed that the technique will become an effective tool for receiving optical data in many flow facilities.

Walking on thin ice! Identifying methamphetamine "drug mules" on digital plain radiography.

PubMed

Abdul Rashid, S N; Mohamad Saini, S B; Abdul Hamid, S; Muhammad, S J; Mahmud, R; Thali, M J; Flach, P M

2014-04-01

The purpose of this study was to retrospectively evaluate the sensitivity, specificity and accuracy of identifying methamphetamine (MA) internal payloads in "drug mules" by plain abdominal digital radiography (DR). The study consisted of 35 individuals suspected of internal MA drug containers. A total of 59 supine digital radiographs were collected. An overall calculation regarding the diagnostic accuracy for all "drug mules" and a specific evaluation concerning the radiological appearance of drug packs as well as the rate of clearance and complications in correlation with the reader's experience were performed. The gold standard was the presence of secured drug packs in the faeces. There were 16 true-positive "drug mules" identified. DR of all drug carriers for Group 1 (forensic imaging experienced readers, n = 2) exhibited a sensitivity of 100%, a mean specificity of 76.3%, positive predictive value (PPV) of 78.5%, negative predictive value (NPV) of 100% and a mean accuracy 87.2%. Group 2 (inexperienced readers, n = 3) showed a lower sensitivity (93.7%), a mean specificity of 86%, a PPV of 86.5%, an NPV of 94.1% and a mean accuracy of 89.5%. The interrater agreement within Group 1 was 0.72 and within Group 2 averaged to 0.79, indicating a fair to very good agreement. DR is a valuable screening tool in cases of MA body packers with huge internal payloads being associated with a high diagnostic insecurity. Diagnostic insecurity on plain films may be overcome by low-dose CT as a cross-sectional imaging modality and addressed by improved radiological education in reporting drug carriers on imaging. Diagnostic signs (double-condom and halo signs) on digital plain radiography are specific in MA "drug mules", although DR is associated with high diagnostic insecurity and underreports the total internal payload.

Ultrasound for Distal Forearm Fracture: A Systematic Review and Diagnostic Meta-Analysis

PubMed Central

Douma-den Hamer, Djoke; Blanker, Marco H.; Edens, Mireille A.; Buijteweg, Lonneke N.; Boomsma, Martijn F.; van Helden, Sven H.; Mauritz, Gert-Jan

2016-01-01

Study Objective To determine the diagnostic accuracy of ultrasound for detecting distal forearm fractures. Methods A systematic review and diagnostic meta-analysis was performed according to the PRISMA statement. We searched MEDLINE, Web of Science and the Cochrane Library from inception to September 2015. All prospective studies of the diagnostic accuracy of ultrasound versus radiography as the reference standard were included. We excluded studies with a retrospective design and those with evidence of verification bias. We assessed the methodological quality of the included studies with the QUADAS-2 tool. We performed a meta-analysis of studies evaluating ultrasound to calculate the pooled sensitivity and specificity with 95% confidence intervals (CI95%) using a bivariate model with random effects. Subgroup and sensitivity analysis were used to examine the effect of methodological differences and other study characteristics. Results Out of 867 publications we included 16 studies with 1,204 patients and 641 fractures. The pooled test characteristics for ultrasound were: sensitivity 97% (CI95% 93–99%), specificity 95% (CI95% 89–98%), positive likelihood ratio (LR) 20.0 (8.5–47.2) and negative LR 0.03 (0.01–0.08). The corresponding pooled diagnostic odds ratio (DOR) was 667 (142–3,133). Apparent differences were shown for method of viewing, with the 6-view method showing higher specificity, positive LR, and DOR, compared to the 4-view method. Conclusion The present meta-analysis showed that ultrasound has a high accuracy for the diagnosis of distal forearm fractures in children when used by proper viewing method. Based on this, ultrasound should be considered a reliable alternative, which has the advantages of being radiation free. PMID:27196439

Image-guided fine-needle aspiration of retroperitoneal masses: The role of the cytopathologist.

PubMed

Mehdi, Ghazala; Maheshwari, Veena; Afzal, Sheerin; Ansari, Hena A; Ahmad, Ibne

2013-01-01

Retroperitoneal tumors constitute a difficult diagnostic category as they are not easily accessible. The advent of image-guided fine-needle aspiration (FNA) has resolved this problem significantly. We present a short study based on guided aspiration of retroperitoneal tumors, in which we have tried to assess the role of image-guided fine-needle aspiration cytology as a tool for pre-operative diagnosis. The study was conducted on patients diagnosed with retroperitoneal masses. FNA was performed under image guidance with the help of ultrasonography and/or computed tomography; smears were prepared and meticulously screened according to a fixed protocol. The results were analyzed to determine sensitivity, specificity, and diagnostic efficacy of cytopathological diagnosis using image-guided FNA techniques. We assessed 38 patients with retroperitoneal masses. In all cases, adequate cellular material was obtained. No major complications were encountered. Statistical analysis was carried out in 35 cases; sensitivity, specificity, and diagnostic accuracy were 100% in these cases. FNA under image guidance should be considered a first-line diagnostic approach for retroperitoneal and other abdominal tumors, although caution should be exercised in case selection. In areas where advanced tests are not available, the cytotechnologist and cytopathologist have a very important role to play in ensuring accurate diagnoses.

Utility of dengue NS1 antigen rapid diagnostic test for use in difficult to reach areas and its comparison with dengue NS1 ELISA and qRT-PCR.

PubMed

Shukla, Mohan K; Singh, Neeru; Sharma, Ravendra K; Barde, Pradip V

2017-07-01

The objective of this study was to demonstrate the utility of dengue virus (DENV) non structural protein 1 (NS1) based rapid diagnostic test (RDT) for use in tribal and difficult to reach areas for early dengue (DEN) diagnosis in acute phase patients and evaluate its sensitivity and specificity against DENV NS1 enzyme linked immune sorbent assay (ELISA) and real time reverse transcriptase polymerase chain reaction (qRT-PCR). The DENV NS1 RDT was used for preliminary diagnosis during outbreaks in difficult to reach rural and tribal areas. The diagnosis was confirmed by DENV NS1 ELISA in the laboratory. The samples were also tested and serotyped by qRT-PCR. The results were evaluated using statistical tests. The DENV NS1 RDT showed 99.2% sensitivity and 96.0% specificity when analyzed using DENV NS1 ELISA as standard. The specificity and sensitivity of the RDT when compared with qRT-PCR was 93.6% and 91.1%, respectively. The serotype specific evaluation showed more than 90% sensitivity and specificity for DENV-1, 2, and 3. The RDT proved a good diagnostic tool in difficult to reach rural and tribal areas. Further evaluation studies with different commercially available RDTs in different field conditions are essential, that will help clinicians and patients for treatment and programme managers for timely intervention. © 2017 Wiley Periodicals, Inc.

Diagnostic accuracy of HLA-B*57:01 screening for the prediction of abacavir hypersensitivity and clinical utility of the test: a meta-analytic review.

PubMed

Cargnin, Sarah; Jommi, Claudio; Canonico, Pier Luigi; Genazzani, Armando A; Terrazzino, Salvatore

2014-05-01

To determine diagnostic accuracy of HLA-B*57:01 testing for prediction of abacavir-induced hypersensitivity and to quantify the clinical benefit of pretreatment screening through a meta-analytic review of published studies. A comprehensive search was performed up to June 2013. The methodological quality of relevant studies was assessed by the QUADAS-2 tool. The pooled diagnostic estimates were calculated using a random effect model. Despite the presence of heterogeneity in sensitivity or specificity estimates, the pooled diagnostic odds ratio to detect abacavir-induced hypersensitivity on the basis of clinical criteria was 33.07 (95% CI: 22.33-48.97, I(2): 13.9%), while diagnostic odds ratio for detection of immunologically confirmed abacavir hypersensitivity was 1141 (95% CI: 409-3181, I(2): 0%). Pooled analysis of risk ratio showed that prospective HLA-B*57:01 testing significantly reduced the incidence of abacavir-induced hypersensitivity. This meta-analysis demonstrates an excellent diagnostic accuracy of HLA-B*57:01 testing to detect immunologically confirmed abacavir hypersensitivity and corroborates existing recommendations.

Analytical Tools to Improve Optimization Procedures for Lateral Flow Assays

PubMed Central

Hsieh, Helen V.; Dantzler, Jeffrey L.; Weigl, Bernhard H.

2017-01-01

Immunochromatographic or lateral flow assays (LFAs) are inexpensive, easy to use, point-of-care medical diagnostic tests that are found in arenas ranging from a doctor’s office in Manhattan to a rural medical clinic in low resource settings. The simplicity in the LFA itself belies the complex task of optimization required to make the test sensitive, rapid and easy to use. Currently, the manufacturers develop LFAs by empirical optimization of material components (e.g., analytical membranes, conjugate pads and sample pads), biological reagents (e.g., antibodies, blocking reagents and buffers) and the design of delivery geometry. In this paper, we will review conventional optimization and then focus on the latter and outline analytical tools, such as dynamic light scattering and optical biosensors, as well as methods, such as microfluidic flow design and mechanistic models. We are applying these tools to find non-obvious optima of lateral flow assays for improved sensitivity, specificity and manufacturing robustness. PMID:28555034

The Berlin Inventory of Gambling behavior - Screening (BIG-S): Validation using a clinical sample.

PubMed

Wejbera, Martin; Müller, Kai W; Becker, Jan; Beutel, Manfred E

2017-05-18

Published diagnostic questionnaires for gambling disorder in German are either based on DSM-III criteria or focus on aspects other than life time prevalence. This study was designed to assess the usability of the DSM-IV criteria based Berlin Inventory of Gambling Behavior Screening tool in a clinical sample and adapt it to DSM-5 criteria. In a sample of 432 patients presenting for behavioral addiction assessment at the University Medical Center Mainz, we checked the screening tool's results against clinical diagnosis and compared a subsample of n=300 clinically diagnosed gambling disorder patients with a comparison group of n=132. The BIG-S produced a sensitivity of 99.7% and a specificity of 96.2%. The instrument's unidimensionality and the diagnostic improvements of DSM-5 criteria were verified by exploratory and confirmatory factor analysis as well as receiver operating characteristic analysis. The BIG-S is a reliable and valid screening tool for gambling disorder and demonstrated its concise and comprehensible operationalization of current DSM-5 criteria in a clinical setting.

Critical comparison of diffuse reflectance spectroscopy and colorimetry as dermatological diagnostic tools for acanthosis nigricans: a chemometric approach

PubMed Central

Devpura, Suneetha; Pattamadilok, Bensachee; Syed, Zain U.; Vemulapalli, Pranita; Henderson, Marsha; Rehse, Steven J.; Hamzavi, Iltefat; Lim, Henry W.; Naik, Ratna

2011-01-01

Quantification of skin changes due to acanthosis nigricans (AN), a disorder common among insulin-resistant diabetic and obese individuals, was investigated using two optical techniques: diffuse reflectance spectroscopy (DRS) and colorimetry. Measurements were obtained from AN lesions on the neck and two control sites of eight AN patients. A principal component/discriminant function analysis successfully differentiated between AN lesion and normal skin with 87.7% sensitivity and 94.8% specificity in DRS measurements and 97.2% sensitivity and 96.4% specificity in colorimetry measurements. PMID:21698027

3-d brownian motion simulator for high-sensitivity nanobiotechnological applications.

PubMed

Toth, Arpád; Banky, Dániel; Grolmusz, Vince

2011-12-01

A wide variety of nanobiotechnologic applications are being developed for nanoparticle based in vitro diagnostic and imaging systems. Some of these systems make possible highly sensitive detection of molecular biomarkers. Frequently, the very low concentration of the biomarkers makes impossible the classical, partial differential equation-based mathematical simulation of the motion of the nanoparticles involved. We present a three-dimensional Brownian motion simulation tool for the prediction of the movement of nanoparticles in various thermal, viscosity, and geometric settings in a rectangular cuvette. For nonprofit users the server is freely available at the site http://brownian.pitgroup.org.

Non-invasive 13C-glucose breath test using residual gas analyzer-mass spectrometry: a novel tool for screening individuals with pre-diabetes and type 2 diabetes.

PubMed

Ghosh, Chiranjit; Maity, Abhijit; Banik, Gourab D; Som, Suman; Chakraborty, Arpita; Selvan, Chitra; Ghosh, Shibendu; Ghosh, Barnali; Chowdhury, Subhankar; Pradhan, Manik

2014-09-01

We report, for the first time, the clinical feasibility of a novel residual gas analyzer mass spectrometry (RGA-MS) method for accurate evaluation of the (13)C-glucose breath test ((13)C-GBT) in the diagnosis of pre-diabetes (PD) and type 2 diabetes mellitus (T2D). In T2D or PD, glucose uptake is impaired and results in blunted isotope enriched (13)CO2 production in exhaled breath samples. Using the Receiver operating characteristics (ROC) curve analysis, an optimal diagnostic cut-off point of the (13)CO2/(12)CO2 isotope ratios expressed as the delta-over-baseline (DOB) value, was determined to be δDOB(13)C‰ = 28.81‰ for screening individuals with non-diabetes controls (NDC) and pre-diabetes (PD), corresponding to a sensitivity of 100% and specificity of 94.4%. We also determined another optimal diagnostic cut-off point of δDOB(13)C‰ = 19.88‰ between individuals with PD and T2D, which exhibited 100% sensitivity and 95.5% specificity. Our RGA-MS methodology for the (13)C-GBT also manifested a typical diagnostic positive and negative predictive value of 96% and 100%, respectively. The diagnostic accuracy, precision and validity of the results were also confirmed by high-resolution optical cavity enhanced integrated cavity output spectroscopy (ICOS) measurements. The δDOB(13)C‰ values measured with RGA-MS method, correlated favourably (R(2) = 0.979) with those determined by the laser based ICOS method. Moreover, we observed that the effects of endogenous CO2 production related to basal metabolic rates in individuals were statistically insignificant (p = 0.37 and 0.73) on the diagnostic accuracy. Our findings suggest that the RGA-MS is a valid and sufficiently robust method for the (13)C-GBT which may serve as an alternative non-invasive point-of-care diagnostic tool for routine clinical practices as well as for large-scale diabetes screening purposes in real-time.

A diagnostic interface for the ICOsahedral Non-hydrostatic (ICON) modelling framework based on the Modular Earth Submodel System (MESSy v2.50)

NASA Astrophysics Data System (ADS)

Kern, Bastian; Jöckel, Patrick

2016-10-01

Numerical climate and weather models have advanced to finer scales, accompanied by large amounts of output data. The model systems hit the input and output (I/O) bottleneck of modern high-performance computing (HPC) systems. We aim to apply diagnostic methods online during the model simulation instead of applying them as a post-processing step to written output data, to reduce the amount of I/O. To include diagnostic tools into the model system, we implemented a standardised, easy-to-use interface based on the Modular Earth Submodel System (MESSy) into the ICOsahedral Non-hydrostatic (ICON) modelling framework. The integration of the diagnostic interface into the model system is briefly described. Furthermore, we present a prototype implementation of an advanced online diagnostic tool for the aggregation of model data onto a user-defined regular coarse grid. This diagnostic tool will be used to reduce the amount of model output in future simulations. Performance tests of the interface and of two different diagnostic tools show, that the interface itself introduces no overhead in form of additional runtime to the model system. The diagnostic tools, however, have significant impact on the model system's runtime. This overhead strongly depends on the characteristics and implementation of the diagnostic tool. A diagnostic tool with high inter-process communication introduces large overhead, whereas the additional runtime of a diagnostic tool without inter-process communication is low. We briefly describe our efforts to reduce the additional runtime from the diagnostic tools, and present a brief analysis of memory consumption. Future work will focus on optimisation of the memory footprint and the I/O operations of the diagnostic interface.

The role of rapid antigen testing for influenza in the era of molecular diagnostics.

PubMed

Dale, Suzanne E

2010-08-01

Rapid antigen testing for influenza has been both maligned and revered since its conception. Microbiologists have long lamented the lack of sensitivity of commercial rapid influenza detection tests (RIDTs), whereas many clinicians have eschewed their utility by emphasizing the value of definitely diagnosing influenza at the patient's bedside. RIDTs, although quick and easy to perform, are widely accepted as being less sensitive than traditional culture techniques and newer molecular methods, including reverse-transcription polymerase chain reaction (RT-PCR). Moreover, the performance characteristics of RIDTs vary widely, and their applications as clinical diagnostic tools are not well understood. In contrast, traditional techniques are time consuming and require significant expertise to perform. Often, the delay in diagnosing influenza through these methods has little impact on patient care. The benefits of achieving a diagnosis of influenza at the point of care are numerous and include increased access to appropriate antivirals, appropriate patient cohorting for infection control purposes, and better resource utilization. Therefore, it behooves the microbiology community to communicate these issues to clinicians and to work to improve the sensitivity of RIDTs.

Ultrasonography and magnetic resonance imaging in the diagnosis of Morton's neuroma.

PubMed

Fazal, Muhammad Ali; Khan, Ishrat; Thomas, Cherian

2012-01-01

Magnetic resonance imaging (MRI) and ultrasonography are used widely for the diagnosis of Morton's neuroma. The aim of this study was to assess the accuracy of these two modalities as diagnostic tools in Morton's neuroma. Fifty feet of 47 consecutive patients (39 women and 8 men; mean age, 46 years; age range, 36-64 years) who presented between January 1, 2005, and June 30, 2008, were included in the study. Twenty-five feet were investigated with ultrasonography and 25 with MRI. Morton's neuroma was confirmed surgically and histologically in all of the patients. A Student unpaired t test was applied. Twenty-two MRIs were diagnostic (sensitivity, 88%). Three patients with negative MRI findings underwent ultrasonography and were found to have a neuroma smaller than 5 mm. Twenty-four ultrasound scans demonstrated the neuroma (sensitivity, 96%), with five neuromas being smaller than 5 mm. Ultrasonography has a slightly higher sensitivity in the diagnosis of Morton's neuroma, particularly of neuromas smaller than 5 mm, and should be the preferred imaging modality in suspected cases, and MRI should be reserved for cases with equivocal diagnosis.

Diagnostic accuracy of interleukin-6 and procalcitonin in patients with periprosthetic joint infection: a systematic review and meta-analysis.

PubMed

Yoon, Jung-Ro; Yang, Se-Hyun; Shin, Young-Soo

2018-06-01

Many studies have found associations between laboratory biomarkers and periprosthetic joint infection (PJI), but it remains unclear whether these biomarkers are clinically useful in ruling out PJI. This meta-analysis compared the performance of interleukin-6 (IL-6) versus procalcitonin (PCT) for the diagnosis of PJI. In this meta-analysis, we reviewed studies that evaluated IL-6 or/and PCT as a diagnostic biomarker for PJI and provided sufficient data to permit sensitivity and specificity analyses for each test. The major databases MEDLINE, EMBASE, the Cochrane Library, Web of Science, and SCOPUS were searched for appropriate studies from the earliest available date of indexing through February 28, 2017. No restrictions were placed on language of publication. We identified 18 studies encompassing a total of 1,835 subjects; 16 studies reported on IL-6 and 6 studies reported on PCT. The area under the curve (AUC) was 0.93 (95% CI, 0.91-0.95) for IL-6 and 0.83 (95% CI, 0.79-0.86) for PCT. The pooled sensitivity was 0.83 (95% CI, 0.74-0.89) for IL-6 and 0.58 (95% CI, 0.31-0.81) for PCT. The pooled specificity was 0.91 (95% CI, 0.84-0.95) for IL-6 and 0.95 (95% CI, 0.63-1.00) for PCT. Both the IL-6 and PCT tests had a high positive likelihood ratio (LR); 9.3 (95% CI, 5.3-16.2) and 12.4 (95% CI, 1.7-89.8), respectively, making them excellent rule-in tests for the diagnosis of PJI. The pooled negative LR for IL-6 was 0.19 (95% CI, 0.12-0.29), making it suitable as a rule-out test, whereas the pooled negative LR for PCT was 0.44 (95% CI, 0.25-0.78), making it unsuitable as a rule-out diagnostic tool. Based on the results of the present meta-analysis, IL-6 has higher diagnostic value than PCT for the diagnosis of PJI. Moreover, the specificity of the IL-6 test is higher than its sensitivity. Conversely, PCT is not recommended for use as a rule-out diagnostic tool.

Accuracy of Pediatric Trauma Field Triage: A Systematic Review.

PubMed

van der Sluijs, Rogier; van Rein, Eveline A J; Wijnand, Joep G J; Leenen, Luke P H; van Heijl, Mark

2018-05-16

Field triage of pediatric patients with trauma is critical for transporting the right patient to the right hospital. Mortality and lifelong disabilities are potentially attributable to erroneously transporting a patient in need of specialized care to a lower-level trauma center. To quantify the accuracy of field triage and associated diagnostic protocols used to identify children in need of specialized trauma care. MEDLINE, Embase, PsycINFO, and Cochrane Register of Controlled Trials were searched from database inception to November 6, 2017, for studies describing the accuracy of diagnostic tests to identify children in need of specialized trauma care in a prehospital setting. Identified articles with a study population including patients not transported by emergency medical services were excluded. Quality assessment was performed using a modified version of the Quality Assessment of Diagnostic Accuracy Studies-2. After deduplication, 1430 relevant articles were assessed, a full-text review of 38 articles was conducted, and 5 of those articles were included. All studies were observational, published between 1996 and 2017, and conducted in the United States, and data collection was prospective in 1 study. Three different protocols were studied that analyzed a combined total of 1222 children in need of specialized trauma care. One protocol was specifically developed for a pediatric out-of-hospital cohort. The percentage of pediatric patients requiring specialized trauma care in each study varied between 2.6% (110 of 4197) and 54.7% (58 of 106). The sensitivity of the prehospital triage tools ranged from 49.1% to 87.3%, and the specificity ranged from 41.7% to 84.8%. No prehospital triage protocol alone complied with the international standard of 95% or greater sensitivity. Undertriage and overtriage rates, representative of the quality of the full diagnostic strategy to transport a patient to the right hospital, were not reported for inclusive trauma systems or emergency medical services regions. It is crucial to transport the right patient to the right hospital. Yet the quality of the full diagnostic strategy to determine the optimal receiving hospital is unknown. None of the investigated field triage protocols complied with current sensitivity targets. Improved efforts are needed to develop accurate child-specific tools to prevent undertriage and its potential life-threatening consequences.

Diagnostic accuracy of metronome-paced tachypnea to detect dynamic hyperinflation.

PubMed

Lahaije, Anke J M C; Willems, Laura M; van Hees, Hieronymus W H; Dekhuijzen, P N Richard; van Helvoort, Hanneke A C; Heijdra, Yvonne F

2013-01-01

This prospective study was carried out to investigate if metronome-paced tachypnea (MPT) can serve as an accurate diagnostic tool to identify patients with chronic obstructive pulmonary disease (COPD) who are susceptible to develop dynamic hyperinflation during exercise. Commonly, this is assessed by measuring change in inspiratory capacity (IC) during cardiopulmonary exercise testing (CPET), which, however, is complex and laborious. Fifty-three patients with COPD (FEV(1) 58 ± 22%pred) and 20 age-matched healthy subjects were characterized by lung function testing and performed CPET (reference standard) and MPT. The repeatability coefficient of IC (10·2%) was used as cut-off to classify subjects as hyperinflators during CPET. Subsequently, dynamic hyperinflation was measured after MPT. With receiver operating characteristic analysis, the optimal cut-off for MPT-induced dynamic hyperinflation was determined and sensitivity and specificity of MPT to identify hyperinflators were evaluated. With 10·2% decrease in IC as cut-off for CPET-induced dynamic hyperinflation, the optimal cut-off for MPT was 11·1% decrease in IC. Using these cut-offs, MPT had a sensitivity of 85% and specificity of 85% to identify the subjects who hyperinflated during CPET. The MPT test shows good overall accuracy to identify subjects who are susceptible to develop dynamic hyperinflation during CPET. Before considering the use of MPT as a screening tool for dynamic hyperinflation in COPD, sensitivity and specificity need further evaluation. © 2012 The Authors Clinical Physiology and Functional Imaging © 2012 Scandinavian Society of Clinical Physiology and Nuclear Medicine.

Loop-mediated isothermal amplification (LAMP) assays for the species-specific detection of Eimeria that infect chickens

PubMed Central

2011-01-01

Background Eimeria parasites can cause the disease coccidiosis in poultry and even subclinical infection can incur economic loss. Diagnosis of infection predominantly relies on traditional techniques including lesion scoring and faecal microscopy despite the availability of sensitive molecular assays, largely due to cost and the requirement for specialist equipment. Despite longstanding proven efficacy these traditional techniques demand time and expertise, can be highly subjective and may under-diagnose subclinical disease. Recognition of the tight economic margins prevailing in modern poultry production and the impact of avian coccidiosis on poverty in many parts of the world has highlighted a requirement for a panel of straightforward and sensitive, but cost-effective, Eimeria species-specific diagnostic assays. Results Loop-mediated isothermal amplification (LAMP) is an uncomplicated, quick and relatively inexpensive diagnostic tool. In this study we have developed a panel of species-specific LAMP assays targeting the seven Eimeria species that infect the chicken. Each assay has been shown to be genuinely species-specific with the capacity to detect between one and ten eimerian genomes, equivalent to less than a single mature schizont. Development of a simple protocol for template DNA preparation from tissue collected post mortem with no requirement for specialist laboratory equipment supports the use of these assays in routine diagnosis of eimerian infection. Preliminary field testing supports this hypothesis. Conclusions Development of a panel of sensitive species-specific LAMP assays introduces a valuable new cost-effective tool for use in poultry husbandry. PMID:22053893

Head-To-Head Comparison Between High- and Standard-b-Value DWI for Detecting Prostate Cancer: A Systematic Review and Meta-Analysis.

PubMed

Woo, Sungmin; Suh, Chong Hyun; Kim, Sang Youn; Cho, Jeong Yeon; Kim, Seung Hyup

2018-01-01

The purpose of this study was to perform a head-to-head comparison between high-b-value (> 1000 s/mm 2 ) and standard-b-value (800-1000 s/mm 2 ) DWI regarding diagnostic performance in the detection of prostate cancer. The MEDLINE and EMBASE databases were searched up to April 1, 2017. The analysis included diagnostic accuracy studies in which high- and standard-b-value DWI were used for prostate cancer detection with histopathologic examination as the reference standard. Methodologic quality was assessed with the revised Quality Assessment of Diagnostic Accuracy Studies tool. Sensitivity and specificity of all studies were calculated and were pooled and plotted in a hierarchic summary ROC plot. Meta-regression and multiple-subgroup analyses were performed to compare the diagnostic performances of high- and standard-b-value DWI. Eleven studies (789 patients) were included. High-b-value DWI had greater pooled sensitivity (0.80 [95% CI, 0.70-0.87]) (p = 0.03) and specificity (0.92 [95% CI, 0.87-0.95]) (p = 0.01) than standard-b-value DWI (sensitivity, 0.78 [95% CI, 0.66-0.86]); specificity, 0.87 [95% CI, 0.77-0.93] (p < 0.01). Multiple-subgroup analyses showed that specificity was consistently higher for high- than for standard-b-value DWI (p ≤ 0.05). Sensitivity was significantly higher for high- than for standard-b-value DWI only in the following subgroups: peripheral zone only, transition zone only, multiparametric protocol (DWI and T2-weighted imaging), visual assessment of DW images, and per-lesion analysis (p ≤ 0.04). In a head-to-head comparison, high-b-value DWI had significantly better sensitivity and specificity for detection of prostate cancer than did standard-b-value DWI. Multiple-subgroup analyses showed that specificity was consistently superior for high-b-value DWI.

Comparative application of IS711-based polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) for canine brucellosis diagnosis.

PubMed

Batinga, Maria Cryskely Agra; de Lima, Julia Teresa Ribeiro; Gregori, Fabio; Diniz, Jaqueline Assumpção; Muner, Kerstin; Oliveira, Trícia M F S; Ferreira, Helena Lage; Soares, Rodrigo Martins; Keid, Lara Borges

2018-06-01

Canine brucellosis is caused by Brucella canis, a gram negative and facultative intracellular bacterium that is commonly associated with reproductive failures in dogs. The accurate diagnosis of the infection relies on the use of serological tests associated with blood culturing to guarantee sensitivity. The polymerase chain reaction (PCR) can replace the culturing procedure for the direct diagnosis of the infection because of its speed, high specificity and sensitivity values; however, it depends on some laboratory infrastructure to be conducted. The loop-mediated isothermal amplification (LAMP) may be an alternative method for DNA amplification in a shorter period, using simpler equipment, and with a lower cost. This study evaluated the potential of molecular tools based on PCR and LAMP using primers targeting the insertion sequence IS711 for Brucella detection in three groups of dogs (infected, non-infected and suspected of brucellosis), which were determined according to the results of blood culturing and clinical examination. The performance of the three diagnostic tests was also determined using McNemar test and Kappa coefficient. The proportion of positive samples detected by blood culturing, PCR and LAMP was respectively 31.57% (18/57), 33.34% (19/57), and 14.03% (8/57). The agreement between blood culturing and PCR was almost perfect, while the agreement of PCR and blood culturing compared to LAMP was fair. The diagnostic sensitivity of PCR and LAMP was respectively 100% (18/18) and 44.44% (8/18), while the diagnostic specificity of both tests was 100% (21/21). LAMP performance was not satisfactory for canine brucellosis diagnosis because of the low diagnostic sensitivity of the test. The IS711 based PCR, otherwise, showed high values of sensitivity and specificity, which makes it a good alternative for use for the rapid diagnosis of canine brucellosis. Copyright © 2018 Elsevier Ltd. All rights reserved.

High-sensitivity MALDI-TOF MS quantification of anthrax lethal toxin for diagnostics and evaluation of medical countermeasures.

PubMed

Boyer, Anne E; Gallegos-Candela, Maribel; Quinn, Conrad P; Woolfitt, Adrian R; Brumlow, Judith O; Isbell, Katherine; Hoffmaster, Alex R; Lins, Renato C; Barr, John R

2015-04-01

Inhalation anthrax has a rapid progression and high fatality rate. Pathology and death from inhalation of Bacillus anthracis spores are attributed to the actions of secreted protein toxins. Protective antigen (PA) binds and imports the catalytic component lethal factor (LF), a zinc endoprotease, and edema factor (EF), an adenylyl cyclase, into susceptible cells. PA-LF is termed lethal toxin (LTx) and PA-EF, edema toxin. As the universal transporter for both toxins, PA is an important target for vaccination and immunotherapeutic intervention. However, its quantification has been limited to methods of relatively low analytic sensitivity. Quantification of LTx may be more clinically relevant than LF or PA alone because LTx is the toxic form that acts on cells. A method was developed for LTx-specific quantification in plasma using anti-PA IgG magnetic immunoprecipitation of PA and quantification of LF activity that co-purified with PA. The method was fast (<4 h total time to detection), sensitive at 0.033 ng/mL LTx in plasma for the fast analysis (0.0075 ng/mL LTx in plasma for an 18 h reaction), precise (6.3-9.9% coefficient of variation), and accurate (0.1-12.7%error; n ≥ 25). Diagnostic sensitivity was 100% (n = 27 animal/clinical cases). Diagnostic specificity was 100% (n = 141). LTx was detected post-antibiotic treatment in 6/6 treated rhesus macaques and 3/3 clinical cases of inhalation anthrax and as long as 8 days post-treatment. Over the course of infection in two rhesus macaques, LTx was first detected at 0.101 and 0.237 ng/mL at 36 h post-exposure and increased to 1147 and 12,107 ng/mL in late-stage anthrax. This demonstrated the importance of LTx as a diagnostic and therapeutic target. This method provides a sensitive, accurate tool for anthrax toxin detection and evaluation of PA-directed therapeutics.

Development and Validation of a Novel Diagnostic Test for Human Brucellosis Using a Glyco-engineered Antigen Coupled to Magnetic Beads

PubMed Central

Ciocchini, Andrés E.; Rey Serantes, Diego A.; Melli, Luciano J.; Iwashkiw, Jeremy A.; Deodato, Bettina; Wallach, Jorge; Feldman, Mario F.; Ugalde, Juan E.; Comerci, Diego J.

2013-01-01

Brucellosis is a highly contagious zoonosis and still a major human health problem in endemic areas of the world. Although several diagnostic tools are available, most of them are difficult to implement especially in developing countries where complex health facilities are limited. Taking advantage of the identical structure and composition of the Brucella spp. and Yersinia enterocolitica O:9 O-polysaccharide, we explored the application of a recombinant Y. enterocolitica O:9-polysaccharide-protein conjugate (OAg-AcrA) as a novel antigen for diagnosis of human brucellosis. We have developed and validated an indirect immunoassay using OAg-AcrA coupled to magnetic beads. OAg-AcrA was produced and purified with high yields in Y. enterocolitica O:9 cells co-expressing the oligosaccharyltransferase PglB and the protein acceptor AcrA of Campylobacter jejuni without the need for culturing Brucella. Expression of PglB and AcrA in Y. enterocolitica resulted in the transfer of the host O-polysaccharide from its lipid carrier to AcrA. To validate the assay and determine the cutoff values, a receiver-operating characteristic analysis was performed using a panel of characterized serum samples obtained from healthy individuals and patients of different clinical groups. Our results indicate that, using this assay, it is possible to detect infection caused by the three main human brucellosis agents (B. abortus, B. melitensis and B. suis) and select different cutoff points to adjust sensitivity and specificity levels as needed. A cutoff value of 13.20% gave a sensitivity of 100% and a specificity of 98.57%, and a cutoff value of 16.15% resulted in a test sensitivity and specificity of 93.48% and 100%, respectively. The high diagnostic accuracy, low cost, reduced assay time and simplicity of this new glycoconjugate-magnetic beads assay makes it an attractive diagnostic tool for using not only in clinics and brucellosis reference laboratories but also in locations with limited laboratory infrastructure and/or minimally trained community health workers. PMID:23459192

Performance of an ultra-sensitive Plasmodium falciparum HRP2-based rapid diagnostic test with recombinant HRP2, culture parasites, and archived whole blood samples.

PubMed

Das, Smita; Peck, Roger B; Barney, Rebecca; Jang, Ihn Kyung; Kahn, Maria; Zhu, Meilin; Domingo, Gonzalo J

2018-03-17

As malaria endemic countries shift from control to elimination, the proportion of low density Plasmodium falciparum infections increases. Current field diagnostic tools, such as microscopy and rapid diagnostic tests (RDT), with detection limits of approximately 100-200 parasites/µL (p/µL) and 800-1000 pg/mL histidine-rich protein 2 (HRP2), respectively, are unable to detect these infections. A novel ultra-sensitive HRP2-based Alere™ Malaria Ag P.f RDT (uRDT) was evaluated in laboratory conditions to define the test's performance against recombinant HRP2 and native cultured parasites. The uRDT detected dilutions of P. falciparum recombinant GST-W2 and FliS-W2, as well as cultured W2 and ITG, diluted in whole blood down to 10-40 pg/mL HRP2, depending on the protein tested. uRDT specificity was 100% against 123 archived frozen whole blood samples. Rapid test cross-reactivity with HRP3 was investigated using pfhrp2 gene deletion strains D10 and Dd2, pfhrp3 gene deletion strain HB3, and controls pfhrp2 and pfhrp3 double deletion strain 3BD5 and pfhrp2 and pfhrp3 competent strain ITG. The commercial Standard Diagnostics, Inc. BIOLINE Malaria Ag P.f RDT (SD-RDT) and uRDT detected pfhrp2 positive strains down to 49 and 3.13 p/µL, respectively. The pfhrp2 deletion strains were detected down to 98 p/µL by both tests. The performance of the uRDT was variable depending on the protein, but overall showed a greater than 10-fold improvement over the SD-RDT. The uRDT also exhibited excellent specificity and showed the same cross-reactivity with HRP3 as the SD-RDT. Together, the results support the uRDT as a more sensitive HRP2 test that could be a potentially effective tool in elimination campaigns. Further clinical evaluations for this purpose are merited.

Diagnostic performance of random urine samples using albumin concentration vs ratio of albumin to creatinine for microalbuminuria screening in patients with diabetes mellitus: a systematic review and meta-analysis.

PubMed

Wu, Hon-Yen; Peng, Yu-Sen; Chiang, Chih-Kang; Huang, Jenq-Wen; Hung, Kuan-Yu; Wu, Kwan-Dun; Tu, Yu-Kang; Chien, Kuo-Liong

2014-07-01

A random urine sample measuring the albumin concentration (UAC) without simultaneously measuring the urinary creatinine is less expensive than measuring the ratio of albumin to creatinine (ACR), but comparisons of their diagnostic performance for microalbuminuria screening among patients with diabetes mellitus (DM) have not been undertaken in previous meta-analyses. To compare the diagnostic performance of the UAC vs the ACR in random urine samples for microalbuminuria screening among patients with DM. Electronic literature searches of PubMed, MEDLINE, and Scopus for English-language publications from the earliest available date of indexing through July 31, 2012. Clinical studies assessing the UAC or the ACR of random urine samples in detecting the presence of microalbuminuria among patients with DM using a urinary albumin excretion rate of 30 to 300 mg/d in 24-hour timed urine collections as the criterion standard. Bivariate random-effects models for analysis and pooling of the diagnostic performance measures across studies, as well as comparisons between different screening tests. The primary end point was the diagnostic performance measures of the UAC or the ACR in random urine samples, as well as comparisons between them. We identified 14 studies, with a total of 2078 patients; 9 studies reported on the UAC, and 12 studies reported on the ACR. Meta-analysis showed pooled sensitivities of 0.85 and 0.87 for the UAC and the ACR, respectively, and pooled specificities of 0.88 and 0.88, respectively. No differences in sensitivity (P = .70), specificity (P = .63), or diagnostic odds ratios (P = .59) between the UAC and the ACR were found. The time point of urine collection did not affect the diagnostic performance of either test. The UAC and the ACR yielded high sensitivity and specificity for the detection of microalbuminuria. Because the diagnostic performance of the UAC is comparable to that of the ACR, our findings indicate that the UAC of random urine samples may become the screening tool of choice for the population with DM, considering the rising incidence of DM and the constrained health care resources in many countries.

Autism detection in early childhood (ADEC): reliability and validity data for a Level 2 screening tool for autistic disorder.

PubMed

Nah, Yong-Hwee; Young, Robyn L; Brewer, Neil; Berlingeri, Genna

2014-03-01

The Autism Detection in Early Childhood (ADEC; Young, 2007) was developed as a Level 2 clinician-administered autistic disorder (AD) screening tool that was time-efficient, suitable for children under 3 years, easy to administer, and suitable for persons with minimal training and experience with AD. A best estimate clinical Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR; American Psychiatric Association, 2000) diagnosis of AD was made for 70 children using all available information and assessment results, except for the ADEC data. A screening study compared these children on the ADEC with 57 children with other developmental disorders and 64 typically developing children. Results indicated high internal consistency (α = .91). Interrater reliability and test-retest reliability of the ADEC were also adequate. ADEC scores reliably discriminated different diagnostic groups after controlling for nonverbal IQ and Vineland Adaptive Behavior Composite scores. Construct validity (using exploratory factor analysis) and concurrent validity using performance on the Autism Diagnostic Observation Schedule (Lord et al., 2000), the Autism Diagnostic Interview-Revised (Le Couteur, Lord, & Rutter, 2003), and DSM-IV-TR criteria were also demonstrated. Signal detection analysis identified the optimal ADEC cutoff score, with the ADEC identifying all children who had an AD (N = 70, sensitivity = 1.0) but overincluding children with other disabilities (N = 13, specificity ranging from .74 to .90). Together, the reliability and validity data indicate that the ADEC has potential to be established as a suitable and efficient screening tool for infants with AD. 2014 APA

Early caries imaging and monitoring with near-infrared light.

PubMed

Fried, Daniel; Featherstone, John D B; Darling, Cynthia L; Jones, Robert S; Ngaotheppitak, Patara; Bühler, Christopher M

2005-10-01

Enamel is highly transparent in the near infrared (NIR); therefore, this region of the electromagnetic spectrum is suited ideally for the development of new optical diagnostic tools for the detection and imaging of early dental caries. This article discusses the NIR optical properties of sound and demineralized dental enamel and the potential use of polarization sensitive optical coherence tomography and NIR transillumination for the imaging of dental caries.

Dental History Predictors of Caries Related Dental Emergencies.

DTIC Science & Technology

1981-11-01

10+) 50% of those with U- lesions would be selected and only 4% of those without disease would be selected. The accuracy of such a system as well as...sufficient sensitivity, specificity, and diagnostic power to be useful as predictive tools. Dental health classification systems are typically only...predicted with some reliability given the intimacy of the relationship and the relatively long duration of the pre-emergency state. The incidence of

Correcting for bias in the selection and validation of informative diagnostic tests.

PubMed

Robertson, David S; Prevost, A Toby; Bowden, Jack

2015-04-15

When developing a new diagnostic test for a disease, there are often multiple candidate classifiers to choose from, and it is unclear if any will offer an improvement in performance compared with current technology. A two-stage design can be used to select a promising classifier (if one exists) in stage one for definitive validation in stage two. However, estimating the true properties of the chosen classifier is complicated by the first stage selection rules. In particular, the usual maximum likelihood estimator (MLE) that combines data from both stages will be biased high. Consequently, confidence intervals and p-values flowing from the MLE will also be incorrect. Building on the results of Pepe et al. (SIM 28:762-779), we derive the most efficient conditionally unbiased estimator and exact confidence intervals for a classifier's sensitivity in a two-stage design with arbitrary selection rules; the condition being that the trial proceeds to the validation stage. We apply our estimation strategy to data from a recent family history screening tool validation study by Walter et al. (BJGP 63:393-400) and are able to identify and successfully adjust for bias in the tool's estimated sensitivity to detect those at higher risk of breast cancer. © 2015 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.

Plant pathogen nanodiagnostic techniques: forthcoming changes?

PubMed Central

Khiyami, Mohammad A.; Almoammar, Hassan; Awad, Yasser M.; Alghuthaymi, Mousa A.; Abd-Elsalam, Kamel A.

2014-01-01

Plant diseases are among the major factors limiting crop productivity. A first step towards managing a plant disease under greenhouse and field conditions is to correctly identify the pathogen. Current technologies, such as quantitative polymerase chain reaction (Q-PCR), require a relatively large amount of target tissue and rely on multiple assays to accurately identify distinct plant pathogens. The common disadvantage of the traditional diagnostic methods is that they are time consuming and lack high sensitivity. Consequently, developing low-cost methods to improve the accuracy and rapidity of plant pathogens diagnosis is needed. Nanotechnology, nano particles and quantum dots (QDs) have emerged as essential tools for fast detection of a particular biological marker with extreme accuracy. Biosensor, QDs, nanostructured platforms, nanoimaging and nanopore DNA sequencing tools have the potential to raise sensitivity, specificity and speed of the pathogen detection, facilitate high-throughput analysis, and to be used for high-quality monitoring and crop protection. Furthermore, nanodiagnostic kit equipment can easily and quickly detect potential serious plant pathogens, allowing experts to help farmers in the prevention of epidemic diseases. The current review deals with the application of nanotechnology for quicker, more cost-effective and precise diagnostic procedures of plant diseases. Such an accurate technology may help to design a proper integrated disease management system which may modify crop environments to adversely affect crop pathogens. PMID:26740775

Recent Advances in Biosensing With Photonic Crystal Surfaces: A Review

PubMed Central

Cunningham, B.T.; Zhang, M.; Zhuo, Y.; Kwon, L.; Race, C.

2016-01-01

Photonic crystal surfaces that are designed to function as wavelength-selective optical resonators have become a widely adopted platform for label-free biosensing, and for enhancement of the output of photon-emitting tags used throughout life science research and in vitro diagnostics. While some applications, such as analysis of drug-protein interactions, require extremely high resolution and the ability to accurately correct for measurement artifacts, others require sensitivity that is high enough for detection of disease biomarkers in serum with concentrations less than 1 pg/ml. As the analysis of cells becomes increasingly important for studying the behavior of stem cells, cancer cells, and biofilms under a variety of conditions, approaches that enable high resolution imaging of live cells without cytotoxic stains or photobleachable fluorescent dyes are providing new tools to biologists who seek to observe individual cells over extended time periods. This paper will review several recent advances in photonic crystal biosensor detection instrumentation and device structures that are being applied towards direct detection of small molecules in the context of high throughput drug screening, photonic crystal fluorescence enhancement as utilized for high sensitivity multiplexed cancer biomarker detection, and label-free high resolution imaging of cells and individual nanoparticles as a new tool for life science research and single-molecule diagnostics. PMID:27642265

A grid matrix-based Raman spectroscopic method to characterize different cell milieu in biopsied axillary sentinel lymph nodes of breast cancer patients.

PubMed

Som, Dipasree; Tak, Megha; Setia, Mohit; Patil, Asawari; Sengupta, Amit; Chilakapati, C Murali Krishna; Srivastava, Anurag; Parmar, Vani; Nair, Nita; Sarin, Rajiv; Badwe, R

2016-01-01

Raman spectroscopy which is based upon inelastic scattering of photons has a potential to emerge as a noninvasive bedside in vivo or ex vivo molecular diagnostic tool. There is a need to improve the sensitivity and predictability of Raman spectroscopy. We developed a grid matrix-based tissue mapping protocol to acquire cellular-specific spectra that also involved digital microscopy for localizing malignant and lymphocytic cells in sentinel lymph node biopsy sample. Biosignals acquired from specific cellular milieu were subjected to an advanced supervised analytical method, i.e., cross-correlation and peak-to-peak ratio in addition to PCA and PC-LDA. We observed decreased spectral intensity as well as shift in the spectral peaks of amides and lipid bands in the completely metastatic (cancer cells) lymph nodes with high cellular density. Spectral library of normal lymphocytes and metastatic cancer cells created using the cellular specific mapping technique can be utilized to create an automated smart diagnostic tool for bench side screening of sampled lymph nodes. Spectral library of normal lymphocytes and metastatic cancer cells created using the cellular specific mapping technique can be utilized to develop an automated smart diagnostic tool for bench side screening of sampled lymph nodes supported by ongoing global research in developing better technology and signal and big data processing algorithms.

Is Diagnostic Performance of Quantitative 2D-Shear Wave Elastography Optimal for Clinical Classification of Benign and Malignant Thyroid Nodules?: A Systematic Review and Meta-analysis.

PubMed

Nattabi, Haliimah A; Sharif, Norhafidzah M; Yahya, Noorazrul; Ahmad, Rozilawati; Mohamad, Mazlyfarina; Zaki, Faizah M; Yusoff, Ahmad N

2017-10-17

This study is a dedicated 2D-shear wave elastography (2D-SWE) review aimed at systematically eliciting up-to-date evidence of its clinical value in differential diagnosis of benign and malignant thyroid nodules. PubMed, Web of Science, and Scopus databases were searched for studies assessing the diagnostic value of 2D-SWE for thyroid malignancy risk stratification published until December 2016. The retrieved titles and abstracts were screened and evaluated according to the predefined inclusion and exclusion criteria. Methodological quality of the studies was assessed using the Quality Assessment of Studies of Diagnostic Accuracy included in Systematic Review 2 (QUADAS-2) tool. Extracted 2D-SWE diagnostic performance data were meta-analyzed to assess the summary sensitivity, specificity, and area under the receiver operating characteristic curve. After stepwise review, 14 studies in which 2D-SWE was used to evaluate 2851 thyroid nodules (1092 malignant, 1759 benign) from 2139 patients were selected for the current study. Study quality on QUADAS-2 assessment was moderate to high. The summary sensitivity, specificity and area under the receiver operating characteristic curve of 2D-SWE for differential diagnosis of benign and malignant thyroid nodules were 0.66 (95% confidence interval [CI]: 0.64-0.69), 0.78 (CI: 0.76-0.80), and 0.851 (Q* = 0.85), respectively. The pooled diagnostic odds ratio, negative likelihood ratio, and positive likelihood ratio were 12.73 (CI: 8.80-18.43), 0.31 (CI: 0.22-0.44), and 3.87 (CI: 2.83-5.29), respectively. Diagnostic performance of quantitative 2D-SWE for malignancy risk stratification of thyroid nodules is suboptimal with mediocre sensitivity and specificity, contrary to earlier reports of excellence. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

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.

Reliability and diagnostic characteristics of the JFK coma recovery scale-revised: exploring the influence of rater's level of experience.

PubMed

Løvstad, Marianne; Frøslie, Kathrine F; Giacino, Joseph T; Skandsen, Toril; Anke, Audny; Schanke, Anne-Kristine

2010-01-01

To confirm the reliability and diagnostic validity of the JFK Coma Recovery Scale-Revised (CRS-R) across raters with varying levels of experience. Thirty-one patients with disorders of consciousness were recruited from 6 Norwegian hospitals. CRS-R and the Disability Rating Scale. Reliability measures were good for the CRS-R total scores and moderate to good for its subscales. Diagnostic agreement among examiners was good. Raters' experience with the CRS-R favorably influenced reliability. Sensitivity and specificity analyses demonstrated better detection of patients in minimally conscious state on the CRS-R relative to the Disability Rating Scale. The CRS-R is a reliable tool for diagnosing vegetative state and minimally conscious state. Raters' level of experience influences the reliability of the CRS-R scores.

Diagnosis of scrub typhus.

PubMed

Janardhanan, Jeshina; Trowbridge, Paul; Varghese, George M

2014-12-01

Scrub typhus is an acute febrile illness that, if untreated, can result in considerable morbidity and mortality. One of the primary reasons for delays in the treatment of this potentially fatal infection is the difficulty in diagnosing the condition. Diagnosis is often complicated because of the combination of non-specific symptoms that overlap with other infections commonly found in endemic areas and the poor available diagnostics. In the majority of the endemic settings, diagnosis still relies on the Weil-Felix test, which is neither sensitive nor specific. Other methods of testing have become available, but at this time, these remain insufficient to provide the rapid point-of-care diagnostics that would be necessary to significantly change the management of this infection by providers in endemic areas. This article reviews the currently available diagnostic tools for scrub typhus and their utility in the clinical setting.

Genetic Determinants of Drug Resistance in Mycobacterium tuberculosis and Their Diagnostic Value.

PubMed

Farhat, Maha R; Sultana, Razvan; Iartchouk, Oleg; Bozeman, Sam; Galagan, James; Sisk, Peter; Stolte, Christian; Nebenzahl-Guimaraes, Hanna; Jacobson, Karen; Sloutsky, Alexander; Kaur, Devinder; Posey, James; Kreiswirth, Barry N; Kurepina, Natalia; Rigouts, Leen; Streicher, Elizabeth M; Victor, Tommie C; Warren, Robin M; van Soolingen, Dick; Murray, Megan

2016-09-01

The development of molecular diagnostics that detect both the presence of Mycobacterium tuberculosis in clinical samples and drug resistance-conferring mutations promises to revolutionize patient care and interrupt transmission by ensuring early diagnosis. However, these tools require the identification of genetic determinants of resistance to the full range of antituberculosis drugs. To determine the optimal molecular approach needed, we sought to create a comprehensive catalog of resistance mutations and assess their sensitivity and specificity in diagnosing drug resistance. We developed and validated molecular inversion probes for DNA capture and deep sequencing of 28 drug-resistance loci in M. tuberculosis. We used the probes for targeted sequencing of a geographically diverse set of 1,397 clinical M. tuberculosis isolates with known drug resistance phenotypes. We identified a minimal set of mutations to predict resistance to first- and second-line antituberculosis drugs and validated our predictions in an independent dataset. We constructed and piloted a web-based database that provides public access to the sequence data and prediction tool. The predicted resistance to rifampicin and isoniazid exceeded 90% sensitivity and specificity but was lower for other drugs. The number of mutations needed to diagnose resistance is large, and for the 13 drugs studied it was 238 across 18 genetic loci. These data suggest that a comprehensive M. tuberculosis drug resistance diagnostic will need to allow for a high dimension of mutation detection. They also support the hypothesis that currently unknown genetic determinants, potentially discoverable by whole-genome sequencing, encode resistance to second-line tuberculosis drugs.

Genetic Determinants of Drug Resistance in Mycobacterium tuberculosis and Their Diagnostic Value

PubMed Central

Sultana, Razvan; Iartchouk, Oleg; Bozeman, Sam; Galagan, James; Sisk, Peter; Stolte, Christian; Nebenzahl-Guimaraes, Hanna; Jacobson, Karen; Sloutsky, Alexander; Kaur, Devinder; Posey, James; Kreiswirth, Barry N.; Kurepina, Natalia; Rigouts, Leen; Streicher, Elizabeth M.; Victor, Tommie C.; Warren, Robin M.; van Soolingen, Dick; Murray, Megan

2016-01-01

Rationale: The development of molecular diagnostics that detect both the presence of Mycobacterium tuberculosis in clinical samples and drug resistance–conferring mutations promises to revolutionize patient care and interrupt transmission by ensuring early diagnosis. However, these tools require the identification of genetic determinants of resistance to the full range of antituberculosis drugs. Objectives: To determine the optimal molecular approach needed, we sought to create a comprehensive catalog of resistance mutations and assess their sensitivity and specificity in diagnosing drug resistance. Methods: We developed and validated molecular inversion probes for DNA capture and deep sequencing of 28 drug-resistance loci in M. tuberculosis. We used the probes for targeted sequencing of a geographically diverse set of 1,397 clinical M. tuberculosis isolates with known drug resistance phenotypes. We identified a minimal set of mutations to predict resistance to first- and second-line antituberculosis drugs and validated our predictions in an independent dataset. We constructed and piloted a web-based database that provides public access to the sequence data and prediction tool. Measurements and Main Results: The predicted resistance to rifampicin and isoniazid exceeded 90% sensitivity and specificity but was lower for other drugs. The number of mutations needed to diagnose resistance is large, and for the 13 drugs studied it was 238 across 18 genetic loci. Conclusions: These data suggest that a comprehensive M. tuberculosis drug resistance diagnostic will need to allow for a high dimension of mutation detection. They also support the hypothesis that currently unknown genetic determinants, potentially discoverable by whole-genome sequencing, encode resistance to second-line tuberculosis drugs. PMID:26910495

A new simple and rapid LC-ESI-MS/MS method for quantification of plasma oxysterols as dimethylaminobutyrate esters. Its successful use for the diagnosis of Niemann-Pick type C disease.

PubMed

Boenzi, Sara; Deodato, Federica; Taurisano, Roberta; Martinelli, Diego; Verrigni, Daniela; Carrozzo, Rosalba; Bertini, Enrico; Pastore, Anna; Dionisi-Vici, Carlo; Johnson, David W

2014-11-01

Two oxysterols, cholestan-3β,5α,6β-triol (C-triol) and 7-ketocholesterol (7-KC), have been recently proposed as diagnostic markers of Niemann-Pick type C (NP-C) disease, representing a potential alternative diagnostic tool to the more invasive and time consuming filipin test in cultured fibroblasts. Usually, the oxysterols are detected and quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) method using atmospheric pressure chemical ionization (APCI) or electro-spray-ionization (ESI) sources, after a variety of derivatization procedures to enhance sensitivity. We developed a sensitive LC-MS/MS method to quantify the oxysterols in plasma as dimethylaminobutyrate ester, suitable for ESI analysis. This method, with an easy liquid-phase extraction and a short derivatization procedure, has been validated to demonstrate specificity, linearity, recovery, lowest limit of quantification, accuracy and precision. The assay was linear over a concentration range of 0.5-200ng/mL for C-triol and 1.0-200ng/mL for 7-KC. Intra-day and inter-day coefficients of variation (CV%) were <15% for both metabolites. Receiver operating characteristic analysis estimates that the area under curve was 0.998 for C-triol, and 0.972 for 7-KC, implying a significant discriminatory power for the method in this patient population of both oxysterols. In summary, our method provides a simple, rapid and non-invasive diagnostic tool for the biochemical diagnosis of NP-C disease. Copyright © 2014 Elsevier B.V. All rights reserved.

Accuracy of clinical diagnosis versus the World Health Organization case definition in the Amoy Garden SARS cohort.

PubMed

Wong, W N; Sek, Antonio C H; Lau, Rick F L; Li, K M; Leung, Joe K S; Tse, M L; Ng, Andy H W; Stenstrom, Robert

2003-11-01

To compare the diagnostic accuracy of emergency department (ED) physicians with the World Health Organization (WHO) case definition in a large community-based SARS (severe acute respiratory syndrome) cohort. This was a cohort study of all patients from Hong Kong's Amoy Garden complex who presented to an ED SARS screening clinic during a 2-month outbreak. Clinical findings and WHO case definition criteria were recorded, along with ED diagnoses. Final diagnoses were established independently based on relevant diagnostic tests performed after the ED visit. Emergency physician diagnostic accuracy was compared with that of the WHO SARS case definition. Sensitivity, specificity, predictive values and likelihood ratios were calculated using standard formulae. During the study period, 818 patients presented with SARS-like symptoms, including 205 confirmed SARS, 35 undetermined SARS and 578 non-SARS. Sensitivity, specificity and accuracy were 91%, 96% and 94% for ED clinical diagnosis, versus 42%, 86% and 75% for the WHO case definition. Positive likelihood ratios (LR+) were 21.1 for physician judgement and 3.1 for the WHO criteria. Negative likelihood ratios (LR-) were 0.10 for physician judgement and 0.67 for the WHO criteria, indicating that clinician judgement was a much more powerful predictor than the WHO criteria. Physician clinical judgement was more accurate than the WHO case definition. Reliance on the WHO case definition as a SARS screening tool may lead to an unacceptable rate of misdiagnosis. The SARS case definition must be revised if it is to be used as a screening tool in emergency departments and primary care settings.

Metabolic and Genetic Screening of Electromagnetic Hypersensitive Subjects as a Feasible Tool for Diagnostics and Intervention

PubMed Central

De Luca, Chiara; Chung Sheun Thai, Jeffrey; Raskovic, Desanka; Cesareo, Eleonora; Caccamo, Daniela; Trukhanov, Arseny

2014-01-01

Growing numbers of “electromagnetic hypersensitive” (EHS) people worldwide self-report severely disabling, multiorgan, non-specific symptoms when exposed to low-dose electromagnetic radiations, often associated with symptoms of multiple chemical sensitivity (MCS) and/or other environmental “sensitivity-related illnesses” (SRI). This cluster of chronic inflammatory disorders still lacks validated pathogenetic mechanism, diagnostic biomarkers, and management guidelines. We hypothesized that SRI, not being merely psychogenic, may share organic determinants of impaired detoxification of common physic-chemical stressors. Based on our previous MCS studies, we tested a panel of 12 metabolic blood redox-related parameters and of selected drug-metabolizing-enzyme gene polymorphisms, on 153 EHS, 147 MCS, and 132 control Italians, confirming MCS altered (P < 0.05–0.0001) glutathione-(GSH), GSH-peroxidase/S-transferase, and catalase erythrocyte activities. We first described comparable—though milder—metabolic pro-oxidant/proinflammatory alterations in EHS with distinctively increased plasma coenzyme-Q10 oxidation ratio. Severe depletion of erythrocyte membrane polyunsaturated fatty acids with increased ω6/ω3 ratio was confirmed in MCS, but not in EHS. We also identified significantly (P = 0.003) altered distribution-versus-control of the CYP2C19∗1/∗2 SNP variants in EHS, and a 9.7-fold increased risk (OR: 95% C.I. = 1.3–74.5) of developing EHS for the haplotype (null)GSTT1 + (null)GSTM1 variants. Altogether, results on MCS and EHS strengthen our proposal to adopt this blood metabolic/genetic biomarkers' panel as suitable diagnostic tool for SRI. PMID:24812443

Evidence assessing the diagnostic performance of medical smartphone apps: a systematic review and exploratory meta-analysis

PubMed Central

Buechi, Rahel; Faes, Livia; Bachmann, Lucas M; Thiel, Michael A; Bodmer, Nicolas S; Schmid, Martin K; Job, Oliver; Lienhard, Kenny R

2017-01-01

Objective The number of mobile applications addressing health topics is increasing. Whether these apps underwent scientific evaluation is unclear. We comprehensively assessed papers investigating the diagnostic value of available diagnostic health applications using inbuilt smartphone sensors. Methods Systematic Review—MEDLINE, Scopus, Web of Science inclusive Medical Informatics and Business Source Premier (by citation of reference) were searched from inception until 15 December 2016. Checking of reference lists of review articles and of included articles complemented electronic searches. We included all studies investigating a health application that used inbuilt sensors of a smartphone for diagnosis of disease. The methodological quality of 11 studies used in an exploratory meta-analysis was assessed with the Quality Assessment of Diagnostic Accuracy Studies 2 tool and the reporting quality with the ’STAndards for the Reporting of Diagnostic accuracy studies' (STARD) statement. Sensitivity and specificity of studies reporting two-by-two tables were calculated and summarised. Results We screened 3296 references for eligibility. Eleven studies, most of them assessing melanoma screening apps, reported 17 two-by-two tables. Quality assessment revealed high risk of bias in all studies. Included papers studied 1048 subjects (758 with the target conditions and 290 healthy volunteers). Overall, the summary estimate for sensitivity was 0.82 (95 % CI 0.56 to 0.94) and 0.89 (95 %CI 0.70 to 0.97) for specificity. Conclusions The diagnostic evidence of available health apps on Apple’s and Google’s app stores is scarce. Consumers and healthcare professionals should be aware of this when using or recommending them. PROSPERO registration number 42016033049. PMID:29247099

Real-time fluorescence loop mediated isothermal amplification for the diagnosis of malaria.

PubMed

Lucchi, Naomi W; Demas, Allison; Narayanan, Jothikumar; Sumari, Deborah; Kabanywanyi, Abdunoor; Kachur, S Patrick; Barnwell, John W; Udhayakumar, Venkatachalam

2010-10-29

Molecular diagnostic methods can complement existing tools to improve the diagnosis of malaria. However, they require good laboratory infrastructure thereby restricting their use to reference laboratories and research studies. Therefore, adopting molecular tools for routine use in malaria endemic countries will require simpler molecular platforms. The recently developed loop-mediated isothermal amplification (LAMP) method is relatively simple and can be improved for better use in endemic countries. In this study, we attempted to improve this method for malaria diagnosis by using a simple and portable device capable of performing both the amplification and detection (by fluorescence) of LAMP in one platform. We refer to this as the RealAmp method. Published genus-specific primers were used to test the utility of this method. DNA derived from different species of malaria parasites was used for the initial characterization. Clinical samples of P. falciparum were used to determine the sensitivity and specificity of this system compared to microscopy and a nested PCR method. Additionally, directly boiled parasite preparations were compared with a conventional DNA isolation method. The RealAmp method was found to be simple and allowed real-time detection of DNA amplification. The time to amplification varied but was generally less than 60 minutes. All human-infecting Plasmodium species were detected. The sensitivity and specificity of RealAmp in detecting P. falciparum was 96.7% and 91.7% respectively, compared to microscopy and 98.9% and 100% respectively, compared to a standard nested PCR method. In addition, this method consistently detected P. falciparum from directly boiled blood samples. This RealAmp method has great potential as a field usable molecular tool for diagnosis of malaria. This tool can provide an alternative to conventional PCR based diagnostic methods for field use in clinical and operational programs.

Diagnostic performance of brain MRI in pharmacovigilance of natalizumab-treated MS patients.

PubMed

Wattjes, Mike P; Wijburg, Martijn T; Vennegoor, Anke; Witte, Birgit I; Roosendaal, Stefan D; Sanchez, Esther; Liu, Yaou; Martins Jarnalo, Carine O; Richert, Nancy D; Uitdehaag, Bernard Mj; Barkhof, Frederik; Killestein, Joep

2016-08-01

In natalizumab-treated multiple sclerosis (MS) patients, magnetic resonance imaging (MRI) is considered as a sensitive tool in detecting both MS disease activity and progressive multifocal leukoencephalopathy (PML). To investigate the performance of neuroradiologists using brain MRI in detecting new MS lesions and asymptomatic PML lesions and in differentiating between MS and PML lesions in natalizumab-treated MS patients. The secondary aim was to investigate interrater variability. In this retrospective diagnostic study, four blinded neuroradiologists assessed reference and follow-up brain MRI scans of 48 natalizumab-treated MS patients with new asymptomatic PML lesions (n = 21) or new MS lesions (n = 20) or no new lesions (n = 7). Sensitivity and specificity for detection of new lesions in general (MS and PML lesions), MS and PML lesion differentiation, and PML detection were determined. Interrater agreement was calculated. Overall sensitivity and specificity for the detection of new lesions, regardless of the nature of the lesions, were 77.4% and 89.3%, respectively; for PML-MS lesion differentiation, 74.2% and 84.7%, respectively; and for asymptomatic PML lesion detection, 59.5% and 91.7%, respectively. Interrater agreement for the tested categories was fair to moderate. The diagnostic performance of trained neuroradiologists using brain MRI in pharmacovigilance of natalizumab-treated MS patients is moderately good. Interrater agreement among trained readers is fair to moderate. © The Author(s), 2015.

Diagnostic value of 3D time-of-flight MRA in trigeminal neuralgia.

PubMed

Cai, Jing; Xin, Zhen-Xue; Zhang, Yu-Qiang; Sun, Jie; Lu, Ji-Liang; Xie, Feng

2015-08-01

The aim of this meta-analysis was to evaluate the diagnostic value of 3D time-of-flight magnetic resonance angiography (3D-TOF-MRA) in trigeminal neuralgia (TN). Relevant studies were identified by computerized database searches supplemented by manual search strategies. The studies were included in accordance with stringent inclusion and exclusion criteria. Following a multistep screening process, high quality studies related to the diagnostic value of 3D-TOF-MRA in TN were selected for meta-analysis. Statistical analyses were conducted using Statistical Analysis Software (version 8.2; SAS Institute, Cary, NC, USA) and Meta Disc (version 1.4; Unit of Clinical Biostatistics, Ramon y Cajal Hospital, Madrid, Spain). For the present meta-analysis, we initially retrieved 95 studies from database searches. A total of 13 studies were eventually enrolled containing a combined total of 1084 TN patients. The meta-analysis results demonstrated that the sensitivity and specificity of the diagnostic value of 3D-TOF-MRA in TN were 95% (95% confidence interval [CI] 0.93-0.96) and 77% (95% CI 0.66-0.86), respectively. The pooled positive likelihood ratio and negative likelihood ratio were 2.72 (95% CI 1.81-4.09) and 0.08 (95% CI 0.06-0.12), respectively. The pooled diagnostic odds ratio of 3D-TOF-MRA in TN was 52.92 (95% CI 26.39-106.11), and the corresponding area under the curve in the summary receiver operating characteristic curve based on the 3D-TOF-MRA diagnostic image of observers was 0.9695 (standard error 0.0165). Our results suggest that 3D-TOF-MRA has excellent sensitivity and specificity as a diagnostic tool for TN, and that it can accurately identify neurovascular compression in TN patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

A meta-analysis of use of Prostate Imaging Reporting and Data System Version 2 (PI-RADS V2) with multiparametric MR imaging for the detection of prostate cancer.

PubMed

Zhang, Li; Tang, Min; Chen, Sipan; Lei, Xiaoyan; Zhang, Xiaoling; Huan, Yi

2017-12-01

This meta-analysis was undertaken to review the diagnostic accuracy of PI-RADS V2 for prostate cancer (PCa) detection with multiparametric MR (mp-MR). A comprehensive literature search of electronic databases was performed by two observers independently. Inclusion criteria were original research using the PI-RADS V2 system in reporting prostate MRI. The methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Data necessary to complete 2 × 2 contingency tables were obtained from the included studies. Thirteen studies (2,049 patients) were analysed. This is an initial meta-analysis of PI-RADs V2 and the overall diagnostic accuracy in diagnosing PCa was as follows: pooled sensitivity, 0.85 (0.78-0.91); pooled specificity, 0.71 (0.60-0.80); pooled positive likelihood ratio (LR+), 2.92 (2.09-4.09); pooled negative likelihood ratio (LR-), 0.21 (0.14-0.31); pooled diagnostic odds ratio (DOR), 14.08 (7.93-25.01), respectively. Positive predictive values ranged from 0.54 to 0.97 and negative predictive values ranged from 0.26 to 0.92. Currently available evidence indicates that PI-RADS V2 appears to have good diagnostic accuracy in patients with PCa lesions with high sensitivity and moderate specificity. However, no recommendation regarding the best threshold can be provided because of heterogeneity. • PI-RADS V2 shows good diagnostic accuracy for PCa detection. • Initially pooled specificity of PI-RADS v2 remains moderate. • PCa detection is increased by experienced radiologists. • There is currently a high heterogeneity in prostate diagnostics with MRI.

It's time to change perspective! New diagnostic tools for lateral elbow pain.

PubMed

Arrigoni, P; Cucchi, D; Menon, A; Randelli, P

2017-12-01

The presence of intra-articular findings that may complement the extra-articular pathology in lateral epicondilytis has been suggested, and a role for minor instability of the elbow as part of the causative process of this disease has been postulated. This study was designed to describe two new clinical tests, aimed at detecting intra-articular pathology in patients affected by recalcitrant lateral epicondylitis and investigate their diagnostic performance. Ten patients suffering of atraumatic lateral elbow pain unresponsive to conservative treatment were considered in this study. Two clinical tests were developed and administrated prior to arthroscopy: Supination and Antero-Lateral pain Test (SALT); Posterior Elbow Pain by Palpation-Extension of the Radiocapitellar joint (PEPPER). Sensitivity, specificity, predictive values and accuracy of SALT and PEPPER as diagnostic tests for seven intra-articular findings were calculated. In 90% of the patients, at least one test was positive. All patients with signs of lateral ligamentous patholaxity or intra-articular abnormal findings had a positive response to at least one of the two tests. SALT proved to have a high sensitivity but a low specificity and is accurate in detecting the presence of intra-articular abnormal findings, especially synovitis. PEPPER test was sensible, specific and accurate in the detection of radial head chondropathy. Two new diagnostic tests (SALT and PEPPER) were specifically designed to evoke pain from intra-articular structures. These tests could be a valid support in the diagnostic algorithm of recalcitrant lateral elbow pain. Positive findings may be indicative of a minor instability of the lateral elbow condition. Diagnostic study, development of diagnostic criteria on basis of consecutive patients, level II.

Residual gas analyzer mass spectrometry for human breath analysis: a new tool for the non-invasive diagnosis of Helicobacter pylori infection.

PubMed

Maity, Abhijit; Banik, Gourab D; Ghosh, Chiranjit; Som, Suman; Chaudhuri, Sujit; Daschakraborty, Sunil B; Ghosh, Shibendu; Ghosh, Barnali; Raychaudhuri, Arup K; Pradhan, Manik

2014-03-01

A residual gas analyzer (RGA) coupled with a high vacuum chamber is described for the non-invasive diagnosis of the Helicobacter pylori (H. pylori) infection through ¹³C-urea breath analysis. The present RGA-based mass spectrometry (MS) method is capable of measuring high-precision ¹³CO₂ isotope enrichments in exhaled breath samples from individuals harboring the H. pylori infection. The system exhibited 100% diagnostic sensitivity, and 93% specificity alongside positive and negative predictive values of 95% and 100%, respectively, compared with invasive endoscopy-based biopsy tests. A statistically sound diagnostic cut-off value for the presence of H. pylori was determined to be 3.0‰ using a receiver operating characteristic curve analysis. The diagnostic accuracy and validity of the results are also supported by optical off-axis integrated cavity output spectroscopy measurements. The δ¹³(DOB)C‰ values of both methods correlated well (R² = 0.9973 at 30 min). The RGA-based instrumental setup described here is simple, robust, easy-to-use and more portable and cost-effective compared to all other currently available detection methods, thus making it a new point-of-care medical diagnostic tool for the purpose of large-scale screening of the H. pylori infection in real time. The RGA-MS technique should have broad applicability for ¹³C-breath tests in a wide range of biomedical research and clinical diagnostics for many other diseases and metabolic disorders.

The CD63 basophil activation test in Hymenoptera venom allergy: a prospective study.

PubMed

Sturm, G J; Böhm, E; Trummer, M; Weiglhofer, I; Heinemann, A; Aberer, W

2004-10-01

The basophil activation test (BAT), which relies on flow cytometric quantitation of the allergen-induced up-regulation of the granule-associated marker CD63 in peripheral blood basophils, has been suggested to be a useful approach in detecting responsiveness to allergens. The purpose of this study was to establish the usefulness of the BAT with regard to the clinical history and current diagnostic tools in Hymenoptera venom allergy using a prospective study design. Fifty-seven consecutive patients allergic to Hymenoptera venom as defined by a systemic reaction after an insect sting, and 30 age- and sex-matched control subjects with a negative history were included. The degree and nature of sensitization was confirmed by skin testing, specific immunoglobulin E (IgE), serum tryptase levels and BAT. In the nonallergic control group only analysis of specific IgE and BAT were performed. Correlation of BAT, skin test and specific IgE, respectively, with the clinical history in the allergic group was termed as sensitivity and in the control group as specificity. Twenty one of 23 (91.3%) bee venom allergic patients and 29 of 34 (85.3%) patients allergic to wasp and hornet venom tested positive in BAT. The overall sensitivity of BAT, specific IgE and skin tests were 87.7, 91.2 and 93.0%, respectively. The overall specificities were 86.7% for BAT and 66.7% for specific IgE. No correlation between the severity of clinical symptoms and the magnitude of basophil activation was observed. The BAT seems to be an appropriate method to identify patients allergic to bee or wasp venom with a comparable sensitivity to standard diagnostic regimens. The higher specificity of BAT as compared with specific IgE makes this test a useful tool in the diagnosis of Hymenoptera venom allergy.

Predictive value of auscultation of femoropopliteal arteries.

PubMed

Kaufmann, Carla; Jacomella, Vincenzo; Kovacicova, Ludmila; Husmann, Marc; Clemens, Robert K; Thalhammer, Christopf; Amann-Vesti, Beatrice R

2013-03-05

Femoropopliteal bruits indicate flow turbulences and increased blood flow velocity, usually caused by an atherosclerotic plaque or stenosis. No data exist on the quality of bruits as a means for quantifying the degree of stenosis. We therefore conducted a prospective observational study to investigate the sensitivity and specificity of femoropopliteal auscultation, differentiated on the basis of bruit quality, to detect and quantify clinically relevant stenoses in patients with symptomatic and asymptomatic peripheral arterial disease (PAD). Patients with known chronic and stable PAD were recruited in the outpatient clinic. We included patients with known PAD and an ankle-brachial index (ABI) <0.90 and/or an ABI ≥0.90 with a history of lower limb revascularisation. Auscultation was performed independently by three investigators with varied clinical experience after a 10-minute period of rest. Femoropopliteal lesions were classified as follows: normal vessel wall or slight wall thickening (<20%), atherosclerotic plaque with below 50% reduction of the vessel lumen, prestenotic/intrastenotic ratio over 2.5 (<70%), over 3.5 (<99%) and complete occlusion (100%). Weighted Cohen's κ coefficients for differentiated auscultation were low in all vascular regions and did not differ between investigators. Sensitivity was low in most areas with an increase after exercise. The highest sensitivity in detecting relevant (>50%) stenosis was found in the common femoral artery (86%). Vascular auscultation is known to be of great use in routine clinical practice in recognising arterial abnormalities. Diagnosis of PAD is based on various diagnostic tools (pulse palpation, ABI measurement) and auscultation can localise relevant stenosis. However, auscultation alone is of limited sensitivity and specificity in grading stenosis in femoropopliteal arteries. Where PAD is clinically suspected further diagnostic tools, especially colour-coded duplex ultrasound, should be employed to quantify the underlying lesion.

The Clinical Utility of Methicillin Resistant Staphylococcus aureus (MRSA) Nasal Screening to Rule Out MRSA Pneumonia: A Diagnostic Meta-analysis with Antimicrobial Stewardship Implications.

PubMed

Parente, Diane M; Cunha, Cheston B; Mylonakis, Eleftherios; Timbrook, Tristan T

2018-01-11

Recent literature has highlighted MRSA nasal screening as a possible antimicrobial stewardship program (ASP) tool for avoiding unnecessary empiric MRSA therapy for pneumonia, yet current guidelines recommend MRSA therapy based on risk factors. The objective of this meta-analysis was to evaluate the diagnostic value of MRSA nasal screening in MRSA pneumonia. Pubmed and EMBASE were searched from inception to November 2016 for English studies evaluating MRSA nasal screening and development of MRSA pneumonia. Data analysis was performed using a bivariate random-effects model to estimate pooled sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values. Twenty-two studies, comprising of 5,163 patients met our inclusion criteria. Pooled sensitivity and specificity of MRSA nares screen for all MRSA pneumonia types was 70.9% and 90.3%, respectively. With a 10% prevalence of potential MRSA pneumonia, the calculated PPV was 44.8% while the NPV was 96.5%. The pooled sensitivity and specificity for MRSA community-acquired pneumonia (CAP) and healthcare-associated pneumonia (HCAP) were at 85% and 92.1%, respectively. For CAP and HCAP both the PPV and NPV increased to 56.8% and 98.1%, respectively. In comparison, for MRSA ventilated-associated pneumonia (VAP), the sensitivity, specificity, PPV, NPV was 40.3%, 93.7%, 35.7%, and 94.8%, respectively. Nares screening for MRSA had a high specificity and NPV for ruling out MRSA pneumonia, particularly in cases of CAP/HCAP. Based on the NPV, utilization of MRSA nares screening is a valuable tool for AMS to streamline empiric antibiotic therapy, especially among patients with pneu. © The Author(s) 2018. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

The diagnostic value and histologic correlate of distinct patterns of shiny white streaks for the diagnosis of melanoma: A retrospective, case-control study.

PubMed

Verzi, Anna Eliza; Quan, Victor L; Walton, Kara E; Martini, Mary C; Marghoob, Ashfaq A; Garfield, Erin M; Kong, Betty Y; Isales, Maria Cristina; VandenBoom, Timothy; Zhang, Bin; West, Dennis P; Gerami, Pedram

2018-05-01

Shiny white streaks (SWSs) are best visualized with polarized dermoscopy and correlate with dermal fibroplasia histopathologically. SWSs have been described at higher frequencies in melanomas than in benign nevi. We assessed the diagnostic value of different patterns of SWSs and their histologic correlate in melanocytic lesions. Polarized dermoscopic images of 1507 histopathologically diagnosed melanocytic neoplasms were analyzed for presence and pattern of SWSs. Histology was also reviewed for correlation. Among 1507 melanocytic neoplasms, SWSs were observed in 31 of 144 melanomas (22%) and 22 of 1363 benign neoplasms (1.6%) (P < .001). The sensitivity and specificity of SWSs for melanoma were 22% and 98%, respectively. Diffuse SWSs exhibited the greatest diagnostic value for melanoma, with sensitivity of 11.8% and specificity of 99.5%. Focal central and peripheral SWSs were comparable in diagnostic significance. The presence of SWSs was highly uncommon in dysplastic nevi, whereas in certain benign subgroups of nevi such as Spitz nevi and atypical genital special site nevi, SWSs were not uncommon. Diffuse SWSs correlated with greater breadth of deep fibroplasia than focal SWSs (P = .009), and SWSs correlated with greater Breslow depth among melanomas (P = .007). This study was retrospective. Polarized dermoscopy is a valuable diagnostic tool in the identification of SWSs, a feature that is highly specific for melanoma. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Evaluation of diagnostic value of four tumor markers in bronchoalveolar lavage fluid of peripheral lung cancer.

PubMed

Li, Jian; Chen, Ping; Mao, Chao-Ming; Tang, Xing-Ping; Zhu, Li-Rong

2014-06-01

The diagnostic role of carcinoembryonic antigen (CEA), squamous cell carcinoma (SCC) antigen, Cyfra 21-1 and neuron-specific enolase (NSE) in the bronchoalveolar lavage fluid (BALF) for lung cancer is still controversial. The aim of this study was to evaluate the diagnostic value of these four tumor markers in BALF for peripheral lung cancer. We measured and compared the levels of CEA, SCC, Cyfra21-1 and NSE in BALF in 42 patients with peripheral lung cancer and 22 patients with benign lung disease. In the patients with peripheral lung cancer, the BAL was separately performed in the bronchus of the tumor-bearing lung and in the corresponding bronchus of the opposite healthy lung. The levels of CEA, SCC, Cyfra21-1 and NSE were significantly elevated in BALF from the tumor-bearing lung compared with the opposite healthy lung in the lung cancer patients (P < 0.001) or the benign lung disease patients (P < 0.005). The diagnostic sensitivities of Cyfra21-1 (86 and 76%), with a specificity of 91%, were the highest among the four tumor markers for the tumor-bearing lung versus the opposite healthy lung and benign lung disease. The combination of Cyfra21-1 and CEA increased the sensitivity to 93 and 86 percent, respectively. The assay of these tumor markers in BALF may be used as a diagnostic tool to complement a cytological examination in the diagnosis of peripheral lung cancer. © 2013 Wiley Publishing Asia Pty Ltd.

Near-infrared confocal micro-Raman spectroscopy combined with PCA-LDA multivariate analysis for detection of esophageal cancer

NASA Astrophysics Data System (ADS)

Chen, Long; Wang, Yue; Liu, Nenrong; Lin, Duo; Weng, Cuncheng; Zhang, Jixue; Zhu, Lihuan; Chen, Weisheng; Chen, Rong; Feng, Shangyuan

2013-06-01

The diagnostic capability of using tissue intrinsic micro-Raman signals to obtain biochemical information from human esophageal tissue is presented in this paper. Near-infrared micro-Raman spectroscopy combined with multivariate analysis was applied for discrimination of esophageal cancer tissue from normal tissue samples. Micro-Raman spectroscopy measurements were performed on 54 esophageal cancer tissues and 55 normal tissues in the 400-1750 cm-1 range. The mean Raman spectra showed significant differences between the two groups. Tentative assignments of the Raman bands in the measured tissue spectra suggested some changes in protein structure, a decrease in the relative amount of lactose, and increases in the percentages of tryptophan, collagen and phenylalanine content in esophageal cancer tissue as compared to those of a normal subject. The diagnostic algorithms based on principal component analysis (PCA) and linear discriminate analysis (LDA) achieved a diagnostic sensitivity of 87.0% and specificity of 70.9% for separating cancer from normal esophageal tissue samples. The result demonstrated that near-infrared micro-Raman spectroscopy combined with PCA-LDA analysis could be an effective and sensitive tool for identification of esophageal cancer.

Usefulness of Four Different Echinococcus granulosus Recombinant Antigens for Serodiagnosis of Unilocular Hydatid Disease (UHD) and Postsurgical Follow-Up of Patients Treated for UHD▿

PubMed Central

Hernández-González, Ana; Muro, Antonio; Barrera, Inmaculada; Ramos, Guillermo; Orduña, Antonio; Siles-Lucas, Mar

2008-01-01

Four different recombinant antigens derived from Echinococcus granulosus, designated B1t, B2t, E14t, and C317, were tested with enzyme-linked immunosorbent assays (ELISAs) for the detection of specific immunoglobulin G (IgG) in patients with unilocular hydatid disease (UHD). The results were compared to those obtained with hydatid fluid and were subjected to receiver operator characteristic analysis. The diagnostic performance of the above-listed proteins was defined with respect to their specificity, sensitivity, and predictive values (PV); the influence of cyst location; and usefulness in the follow-up of surgical treatment for UHD and in the determination of whether or not patients have been surgically cured of UHD. The best diagnostic results were obtained with the anti-B2t IgG ELISA, with 91.2% sensitivity, 93% specificity, and high positive and negative PV (89.4 and 94.2, respectively). In addition, this diagnostic tool proved to be useful for the follow-up of surgically treated UHD patients. The anti-B2t IgG ELISA may find an application in the serodiagnosis of UHD in clinical laboratories. PMID:17989342

Sensitivity of Helicobacter pylori detection by Giemsa staining is poor in comparison with immunohistochemistry and fluorescent in situ hybridization and strongly depends on inflammatory activity.

PubMed

Kocsmár, Éva; Szirtes, Ildikó; Kramer, Zsófia; Szijártó, Attila; Bene, László; Buzás, György Miklós; Kenessey, István; Bronsert, Peter; Csanadi, Agnes; Lutz, Lisa; Werner, Martin; Wellner, Ulrich Friedrich; Kiss, András; Schaff, Zsuzsa; Lotz, Gábor

2017-08-01

Conventional stainings (including H&E and special stains like Giemsa) are the most widely applied histopathologic detection methods of Helicobacter pylori (HP). We aimed to compare the diagnostic performance of Giemsa staining with immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) on a monocentric cohort of 2896 gastric biopsies and relate results to histologic alterations in order to find such histopathologic subgroups in which these methods underperform. All cases were categorized regarding presence or absence of chronic gastritis, inflammatory activity, and mucosal structural alterations. Giemsa revealed 687 cases (23.7%), IHC 795 cases (27.5%), and FISH 788 cases (27.2%) as being HP positive. Giemsa showed significantly lower overall sensitivity (83.3%) compared to IHC (98.8%) and FISH (98.0%). Moreover, the sensitivity of Giemsa dramatically dropped to 33.6% in the nonactive cases. We found that sensitivity of Giemsa strongly depends on HP density and, accordingly, on the presence of activity. Structural alterations (intestinal metaplasia, atrophy, etc.) had only no or weak effect on sensitivity of the three stainings. Both IHC and FISH proved to be equally reliable HP detecting techniques whose diagnostic performance is minimally influenced by mucosal inflammatory and structural alterations contrary to conventional stainings. We highly recommend immunohistochemistry for clinically susceptible, nonactive chronic gastritis cases, if the conventional stain-based HP detection is negative. Moreover, we recommend to use IHC more widely as basic HP stain. Helicobacter pylori FISH technique is primarily recommended to determine bacterial clarithromycin resistance. Furthermore, it is another accurate diagnostic tool for HP. © 2017 John Wiley & Sons Ltd.

Performance of a High-Sensitivity Rapid Diagnostic Test for Plasmodium falciparum Malaria in Asymptomatic Individuals from Uganda and Myanmar and Naive Human Challenge Infections.

PubMed

Das, Smita; Jang, Ihn Kyung; Barney, Becky; Peck, Roger; Rek, John C; Arinaitwe, Emmanuel; Adrama, Harriet; Murphy, Maxwell; Imwong, Mallika; Ling, Clare L; Proux, Stephane; Haohankhunnatham, Warat; Rist, Melissa; Seilie, Annette M; Hanron, Amelia; Daza, Glenda; Chang, Ming; Nakamura, Tomoka; Kalnoky, Michael; Labarre, Paul; Murphy, Sean C; McCarthy, James S; Nosten, Francois; Greenhouse, Bryan; Allauzen, Sophie; Domingo, Gonzalo J

2017-11-01

Sensitive field-deployable diagnostic tests can assist malaria programs in achieving elimination. The performance of a new Alere™ Malaria Ag P.f Ultra Sensitive rapid diagnostic test (uRDT) was compared with the currently available SD Bioline Malaria Ag P.f RDT in blood specimens from asymptomatic individuals in Nagongera, Uganda, and in a Karen Village, Myanmar, representative of high- and low-transmission areas, respectively, as well as in pretreatment specimens from study participants from four Plasmodium falciparum -induced blood-stage malaria (IBSM) studies. A quantitative reverse transcription PCR (qRT-PCR) and a highly sensitive enzyme-linked immunosorbent assay (ELISA) test for histidine-rich protein II (HRP2) were used as reference assays. The uRDT showed a greater than 10-fold lower limit of detection for HRP2 compared with the RDT. The sensitivity of the uRDT was 84% and 44% against qRT-PCR in Uganda and Myanmar, respectively, and that of the RDT was 62% and 0% for the same two sites. The specificities of the uRDT were 92% and 99.8% against qRT-PCR for Uganda and Myanmar, respectively, and 99% and 99.8% against the HRP2 reference ELISA. The RDT had specificities of 95% and 100% against qRT-PCR for Uganda and Myanmar, respectively, and 96% and 100% against the HRP2 reference ELISA. The uRDT detected new infections in IBSM study participants 1.5 days sooner than the RDT. The uRDT has the same workflow as currently available RDTs, but improved performance characteristics to identify asymptomatic malaria infections. The uRDT may be a useful tool for malaria elimination strategies.

Performance of a High-Sensitivity Rapid Diagnostic Test for Plasmodium falciparum Malaria in Asymptomatic Individuals from Uganda and Myanmar and Naive Human Challenge Infections

PubMed Central

Das, Smita; Jang, Ihn Kyung; Barney, Becky; Peck, Roger; Rek, John C.; Arinaitwe, Emmanuel; Adrama, Harriet; Murphy, Maxwell; Imwong, Mallika; Ling, Clare L.; Proux, Stephane; Haohankhunnatham, Warat; Rist, Melissa; Seilie, Annette M.; Hanron, Amelia; Daza, Glenda; Chang, Ming; Nakamura, Tomoka; Kalnoky, Michael; Labarre, Paul; Murphy, Sean C.; McCarthy, James S.; Nosten, Francois; Greenhouse, Bryan; Allauzen, Sophie; Domingo, Gonzalo J.

2017-01-01

Abstract. Sensitive field-deployable diagnostic tests can assist malaria programs in achieving elimination. The performance of a new Alere™ Malaria Ag P.f Ultra Sensitive rapid diagnostic test (uRDT) was compared with the currently available SD Bioline Malaria Ag P.f RDT in blood specimens from asymptomatic individuals in Nagongera, Uganda, and in a Karen Village, Myanmar, representative of high- and low-transmission areas, respectively, as well as in pretreatment specimens from study participants from four Plasmodium falciparum-induced blood-stage malaria (IBSM) studies. A quantitative reverse transcription PCR (qRT-PCR) and a highly sensitive enzyme-linked immunosorbent assay (ELISA) test for histidine-rich protein II (HRP2) were used as reference assays. The uRDT showed a greater than 10-fold lower limit of detection for HRP2 compared with the RDT. The sensitivity of the uRDT was 84% and 44% against qRT-PCR in Uganda and Myanmar, respectively, and that of the RDT was 62% and 0% for the same two sites. The specificities of the uRDT were 92% and 99.8% against qRT-PCR for Uganda and Myanmar, respectively, and 99% and 99.8% against the HRP2 reference ELISA. The RDT had specificities of 95% and 100% against qRT-PCR for Uganda and Myanmar, respectively, and 96% and 100% against the HRP2 reference ELISA. The uRDT detected new infections in IBSM study participants 1.5 days sooner than the RDT. The uRDT has the same workflow as currently available RDTs, but improved performance characteristics to identify asymptomatic malaria infections. The uRDT may be a useful tool for malaria elimination strategies. PMID:28820709

Characterization and Plasma Measurement of the WE-14 Peptide in Patients with Pheochromocytoma

PubMed Central

Guillemot, Johann; Guérin, Marlène; Thouënnon, Erwan; Montéro-Hadjadje, Maité; Leprince, Jérôme; Lefebvre, Hervé; Klein, Marc; Muresan, Mihaela; Anouar, Youssef; Yon, Laurent

2014-01-01

Granins and their derived peptides are valuable circulating biological markers of neuroendocrine tumors. The aim of the present study was to investigate the tumoral chromogranin A (CgA)-derived peptide WE-14 and the potential advantage to combine plasma WE-14 detection with the EM66 assay and the existing current CgA assay for the diagnosis of pheochromocytoma. Compared to healthy volunteers, plasma WE-14 levels were 5.4-fold higher in patients with pheochromocytoma, but returned to normal values after surgical resection of the tumor. Determination of plasma CgA and EM66 concentrations in the same group of patients revealed that the test assays for these markers had an overall 84% diagnostic sensitivity, which is identical to that determined for WE-14. However, we found that WE-14 measurement improved the diagnostic sensitivity when combined with the results of CgA or EM66 assays. By combining the results of the three assays, the sensitivity for the diagnosis of pheochromocytoma was increased to 95%. In fact, the combination of WE-14 with either CgA or EM66 test assays achieved 100% sensitivity for the diagnosis of paragangliomas and sporadic or malignant pheochromocytomas if taken separately to account for the heterogeneity of the tumor. These data indicate that WE-14 is produced in pheochromocytoma and secreted into the general circulation, and that elevated plasma WE-14 levels are correlated with the occurrence of this chromaffin cell tumor. In addition, in association with other biological markers, such as CgA and/or EM66, WE-14 measurement systematically improves the diagnostic sensitivity for pheochromocytoma. These findings support the notion that granin-processing products may represent complementary tools for the diagnosis of neuroendocrine tumors. PMID:24523932

The recomBead Borrelia antibody index, CXCL13 and total IgM index for laboratory diagnosis of Lyme neuroborreliosis in children.

PubMed

Skogman, B H; Lager, M; Henningsson, A J; Tjernberg, I

2017-11-01

For laboratory diagnostics of Lyme neuroborreliosis (LNB), the recomBead Borrelia antibody index (AI) assay has shown promising results in a mixed age population, but has not previously been evaluated with specific focus on paediatric patients. The aim of the study was to evaluate the recomBead Borrelia AI assay in cerebrospinal fluid (CSF) for the laboratory diagnosis of LNB in children. We also wanted to explore whether early markers, such as CXCL13 in CSF and/or total IgM index could be useful as complementary diagnostic tools. Children being evaluated for LNB in a Swedish Lyme endemic area were included in the study (n = 146). Serum and CSF were collected on admission. Patients with other specific diagnoses were controls (n = 15). The recomBead Borrelia AI assay and the recomBead CXCL13 assay (Mikrogen) were applied together with total IgM index. The overall sensitivity for recomBead Borrelia AI (IgM and IgG together) was 74% and the specificity was 97%. However, the highest sensitivity (91%) at an acceptable level of specificity (90%) was obtained by recomBead Borrelia AI together with CXCL13 and total IgM index, showing a positive predictive value of 84% and a negative predictive value of 95%. Thus, the recomBead Borrelia AI assay performs with moderate sensitivity and high specificity in paediatric LNB patients. The major advantage seems to be increased sensitivity in the possible LNB group compared to the IDEIA assay. The diagnostic sensitivity may be further increased by using a combination of early markers, such as CXCL13 in CSF and total IgM index.

The Validity of the Montgomery-Asberg Depression Rating Scale in an Inpatient Sample with Alcohol Dependence

PubMed Central

Hobden, Breanne; Schwandt, Melanie L.; Carey, Mariko; Lee, Mary R.; Farokhnia, Mehdi; Bouhlal, Sofia; Oldmeadow, Christopher; Leggio, Lorenzo

2017-01-01

Background The Montgomery-Asberg Depression Rating Scale (MADRS) is commonly used to examine depressive symptoms in clinical settings, including facilities treating patients for alcohol addiction. No studies have examined the validity of the MADRS compared to an established clinical diagnostic tool of depression in this population. This study aimed to examine: 1) the validity of the MADRS compared to a clinical diagnosis of a depressive disorder (using the Structured Clinical Interview for DSM-IV (SCID)) in patients seeking treatment for alcohol dependence (AD); 2) whether the validity of the MADRS differs by type of SCID-based diagnosis of depression; and 3) which items contribute to the optimal predictive model of the MADRS compared to a SCID diagnosis of a depressive disorder. Methods Individuals seeking treatment for AD and admitted to an inpatient unit were administered the MADRS at day 2 of their detoxification program. Clinical diagnoses of AD and depression were made via the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders-IV at the beginning of treatment. Results In total, 803 participants were included in the study. The MADRS demonstrated low overall accuracy relative to the clinical diagnosis of depression with an area under the curve of 0.68. The optimal threshold for balancing sensitivity and specificity identified by the Euclidean distance was >14. This cut-point demonstrated a sensitivity of 66%, a specificity of 60%, a positive predictive value of 50% and a negative predictive value of 75%. The MADRS performed slightly better for major depressive disorders compared to alcohol-induced depression. Items related to lassitude, concentration and appetite slightly decreased the accuracy of the MADRS. Conclusion The MADRS does not appear to be an appropriate substitute for a diagnostic tool among alcohol-dependent patients. The MADRS may, however, still be a useful screening tool assuming careful consideration of cut-off scores. PMID:28421616

Inherent Contrast in Magnetic Resonance Imaging and the Potential for Contrast Enhancement

PubMed Central

Brasch, Robert C.

1985-01-01

Magnetic resonance (MR) imaging is emerging as a powerful new diagnostic tool valued for its apparent lack of adverse effects. The excellent inherent contrast between biologic tissues and fluids afforded by MR imaging is one of the foremost characteristics of this technique and depends on physicochemical properties such as hydrogen density and T1 and T2 relaxation rates, on magnetic field strength and on operator-chosen factors for acquiring the MR imaging signal. Pharmaceutical contrast-enhancing agents shorten the MR imaging process and improve sensitivity and diagnostic accuracy. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 8.Figure 9.Figure 10.Figure 11. PMID:2992172

Xpert MTB/RIF assay can be used on archived gastric aspirate and induced sputum samples for sensitive diagnosis of paediatric tuberculosis.

PubMed

Singh, Sarman; Singh, Amit; Prajapati, Suneel; Kabra, Sushil K; Lodha, Rakesh; Mukherjee, Aparna; Singh, Varinder; Hesseling, Anneke C; Grewal, Harleen M S

2015-09-29

Tuberculosis (TB) in children is neglected, mainly due to lack of sensitive diagnostic tools. Recently Xpert MTB/RIF assay has revolutionized the diagnostic field, but its usefulness in pediatric TB has not been reported from India and no report is available on its use on long term archived samples. We recruited 130 pediatric patients with probable intrathoracic tuberculosis and their gastric aspirate (GA) and induced sputum (IS) samples on 2 consecutive days were collected between January 2009 and December 2012. All samples (n = 520) were subjected to smear examination, BACTEC-MGIT culture and in-house multiplex PCR. An aliquot of each sample was stored at -80 °C and tested in Xpert MTB/RIF assay in 2013. Sample wise and patient wise detection rate of smear microscopy was 4.4 % and 10 %, while for BACTEC-MGIT culture this rate was 24.4 % and 46.9 %, respectively. Of the 130 day 1 GA samples, 31.5 % and 27.7 % day 2 GA samples were culture positive. Only 17.7 % GA samples were positive on both days. Of the 130 IS samples collected on day 1 and day 2, 15.4 % and 23.1 % samples were culture positive. A combination of GA and IS yielded best results. Combining both GA and IS, the overall sensitivity of Xpert MTB/RIF on smear and culture positive samples was 95.6 %. In smear negative and culture positive samples its sensitivity was 62.5 %. The duration of sample storage impacted the Xpert MTB/RIF test performance (p = 0.0001). In smear positive samples stored for 650-849 days, its sensitivity was 85.7 % and 77.1 % for IS and GA samples which dropped to 33.3 % and 50 %, respectively, if stored for more than 1050 days. Confirmatory diagnosis of tuberculosis particularly in children is a medical challenge. No laboratory or radiological test can reach to a satisfactory level of diagnostic sensitivity. However, in this study we found that combination of multiple samples and multiple diagnostic tests can give much better yield, though not optimum. In present study, combination of 2 gastric aspirates (GA) and 2 induced sputum (IS) samples collected on two consecutive days, and tested on three diagnostic methods yielded a significantly high detection rate. Despite long term storage, the overall sensitivity of Xpert MTB/RIF on smear and -culture positive samples remained very high. But after storing these samples under subfreezing conditions the sensitivity of Xpert MTB/RIF decreased significantly. This is expected because even if the sample is smear and culture positive, the count of surviving mycobacteria goes down, after several years this count can reach to a undetectable level. This report shows that smear and culture positive samples stored at subfreezing conditions for several years can be used in the Xpert MTB/RIF assay, while maintaining appreciable diagnostic test sensitivity and specificity.

The Diagnostic Accuracy of the Berg Balance Scale in Predicting Falls.

PubMed

Park, Seong-Hi; Lee, Young-Shin

2017-11-01

This study aimed to evaluate the predictive validity of the Berg Balance Scale (BBS) as a screening tool for fall risks among those with varied levels of balance. A total of 21 studies reporting predictive validity of the BBS of fall risk were meta-analyzed. With regard to the overall predictive validity of the BBS, the pooled sensitivity and specificity were 0.72 and 0.73, respectively; the accuracy curve area was 0.84. The findings showed statistical heterogeneity among studies. Among the sub-groups, the age group of those younger than 65 years, those with neuromuscular disease, those with 2+ falls, and those with a cutoff point of 45 to 49 showed better sensitivity with statistically less heterogeneity. The empirical evidence indicates that the BBS is a suitable tool to screen for the risk of falls and shows good predictability when used with the appropriate criteria and applied to those with neuromuscular disease.

Gram staining in the diagnosis of acute septic arthritis.

PubMed

Faraj, A A; Omonbude, O D; Godwin, P

2002-10-01

This study aimed at determining the sensitivity and specificity of Gram staining of synovial fluid as a diagnostic tool in acute septic arthritis. A retrospective study was made of 22 patients who had arthroscopic lavage following a provisional diagnosis of acute septic arthritis of the knee joint. Gram stains and cultures of the knee aspirates were compared with the clinical and laboratory parameters, to evaluate their usefulness in diagnosing acute arthritis. All patients who had septic arthritis had pain, swelling and limitation of movement. CRP was elevated in 90% of patients. The incidence of elevated white blood cell count was higher in the group of patients with a positive Gram stain study (60%) as compared to patients with a negative Gram stain study (33%). Gram staining sensitivity was 45%. Its specificity was however 100%. Gram staining is an unreliable tool in early decision making in patients requiring urgent surgical drainage and washout.

Fluorescence diagnostics in oncological gynecology

NASA Astrophysics Data System (ADS)

Belyaeva, Ludmila A.; Adamyan, Leila V.; Kozachenko, Vladimir P.; Stratonnikov, Alexander A.; Stranadko, Eugene F.; Loschenov, Victor B.

2003-10-01

The method of fluorescent diagnostics (FD) of tumors is a promising tool that may allow to increase sensitivity of tumor detection especially at initial stages. One of the most promising photosensitizers today is 5-aminolevulinic acid (5-ALA) that, actually, is not photosensitizer itself but precursor of protoporphyrin IX (PpIX). This paper deals with cancer diagnostics in gynecology by means of ALA-induced Pp IX laser-fluorescence spectroscopy. The tissue fluorescence spectra in vivo were studied in patients with various pathologies of ovaries, uterine and vulva after 5-aminolevulinic acid administration. It was shown that different pathologies varies in accumulation of Pp IX. Coefficient of fluorescence kf for normal tissue is not high, but exceptions are endometrium and mucous membrane of uterine tubes. Benign tumors of uterus and ovary have low values of kf, but polyps of endometrium exhibit high kf. Optical express-biopsy is important for diagnosis of ovarian cancer and micrometastatic spread. Coefficients of diagnostic contrast were determined for cancer of endometrium, cervical cancer, vulvar cancer.

Hepatocellular carcinoma and microRNA: new perspectives on therapeutics and diagnostics.

PubMed

Yang, Ningning; Ekanem, Nsikak R; Sakyi, Clement A; Ray, Sidhartha D

2015-01-01

Hepatocellular carcinoma (HCC) remains one of the most lethal forms of cancer in the world. In this arena, utilities of microRNA (miRNA) as a sophisticated tool, in therapeutics and diagnostics, remains a prime focus among the leading researchers. It is well known that viral hepatitis, chronic alcoholism and metabolic syndrome are the prime causes of HCCs. Nevertheless, HCCs are usually diagnosed at late stages by using current serum biomarkers. Most epidemiological studies have found the survival rate in HCC cases to be relatively low. Therefore, development of effective noninvasive biomarkers for early detention of HCC and new strategies for HCC treatment remains a high priority research area on the shoulders of liver oncologists. Accumulating evidence in cancer diagnostics and therapeutics indicates that miRNAs involve in HCC progression, which may serve as sensitive biomarkers for detecting carcinogenesis and monitoring therapies of HCC. This review focuses on the role of miRNAs in the diagnostics and therapeutics of HCC. Copyright © 2014 Elsevier B.V. All rights reserved.

Remote Skin Tissue Diagnostics In Vivo By Fiber Optic Evanescent Wave Fourier Transform Infrared (FEW-FTIR) Spectroscopy

NASA Astrophysics Data System (ADS)

Kolyakov, Sergei; Afanasyeva, Natalia; Bruch, Reinhard; Afanasyeva, Natalia

1998-05-01

The new method of fiber optical evanescent wave Fourier transform infrared (FEW-FTIR) spectroscopy has been applied to the diagnostics of normal skin tissue, as well as precancerous and cancerous conditions. The FEW-FTIR technique is nondestructive and sensitive to changes of vibrational spectra in the IR region, without heating and damaging human and animal skin tissue. Therefore this method and technique is an ideal diagnostic tool for tumor and cancer characterization at an early stage of development on a molecular level. The application of fiber optic technology in the middle infrared (MIR) region is relatively inexpensive and can be adapted easily to any commercially available tabletop FTIR spectrometers. This method of diagnostics is fast (several seconds), and can be applied to many fields. Noninvasive medical diagnostics of skin cancer and other skin diseases in vivo, ex vivo, and in vitro allow for the development of convenient, remote clinical applications in dermatology and related fields. The spectral variations from normal to pathological skin tissue and environmental influence on skin have been measured.

An electronic thesaurus of Evidence Based Laboratory Medicine hematological and biochemical diagnostic tests.

PubMed

Dorizzi, R M; Maconi, M; Giavarina, D; Loza, G; Aman, M; Moreira, J; Bisoffi, Z; Gennuso, C

2009-10-01

The adoption of Evidence Based Laboratory Medicine (EBLM) has been hampered until today by the lack of effective tools. The SIMeL EBLM e-Thesaurus (on-line Repertoire of the diagnostic effectiveness of the laboratory, radiology and cardiology test) provides a useful support to clinical laboratory professionals and to clinicians for the interpretation of the diagnostic tests. The e-Thesaurus is an application developed using Microsoft Active Server Pages technology and carried out with Web Server Microsoft Internet Information Server and is available at the SIMeL website using a browser running JavaScript scripts (Internet Explorer is recommended). It contains a database (in Italian, English and Spanish) of the sensitivity and specificity (including the 95% confidence interval), the positive and negative likelihood ratios, the Diagnostic Odds Ratio and the Number Needed to Diagnose of more than 2000 diagnostic (most laboratory but also cardiology and radiology) tests. The e-Thesaurus improves the previous SIMeL paper and CD Thesaurus; its main features are a three languages search and a continuous and an easy updating capability.

Diagnosis of Hirschsprung's disease with particular emphasis on histopathology. A systematic review of current literature

PubMed Central

Szylberg, Łukasz

2014-01-01

Hirschsprung's disease (HD) is a disorder that involves several medical specialties such as paediatric gastroenterology, paediatric surgery, and pathology. Hirschsprung's disease is a congenital bowel innervation disorder characterised by the absence of ganglion cells in myenteric (Auerbach) and submucosal (Meissner) plexus in the distal colon in its classical form. Rapid and accurate diagnosis of HD is a key element in further treatment patterns. The efficiency of different diagnostic methods used in HD patients may vary. Using one limited diagnostic procedure can lead to as much as a few per cent of overlooked cases. In recent years, rectal biopsy was recognised as an important diagnostic tool that allows for a definitive HD diagnosis with an accuracy of 95% of cases. A correct diagnosis depends on the localisation of the biopsied sample, its representativeness, the number of specimens, and proper interpretation of microscopic studies supported by histochemical and immunohistochemical methods. When several methods are used and all diagnostic criteria are used, the diagnostic sensitivity can almost eliminate cases of undiagnosed patients. PMID:25395999

Development and evaluation of a novel LAMP assay for the diagnosis of Cutaneous and Visceral Leishmaniasis.

PubMed

Adams, Emily Rebecca; Schoone, Gerard; Versteeg, Inge; Gomez, Maria Adelaida; Diro, Ermias; Mori, Yasuyoshi; Perlee, Desiree; Downing, Tim; Saravia, Nancy; Assaye, Ashenafi; Hailu, Asrat; Albertini, Audrey; Ndung'u, Joseph Mathu; Schallig, Henk

2018-04-25

A novel Pan-Leishmania LAMP assay was developed for diagnosis of Cutaneous and Visceral Leishmaniasis (CL & VL) which can be used in near-patient settings. Primers were designed on the 18S rDNA and the conserved region of minicircle kDNA selected on the basis of high copy number. LAMP assays were evaluated for CL in a prospective cohort trial of 105 patients in South-West Colombia. Lesion swab samples from CL suspects were collected and tested using LAMP and compared to a composite reference of microscopy AND/OR culture to calculate diagnostic accuracy. LAMP assays were tested on 50 VL suspected patients from Ethiopia, including whole blood, peripheral blood mononuclear cells, and buffy coat. Diagnostic accuracy was calculated against a reference standard of microscopy of splenic or bone marrow aspirates. To calculate analytical specificity 100 clinical samples and isolates with fever causing pathogens including malaria, arboviruses and bacterial infections were tested. The LAMP assay had a sensitivity of 95% (95% CI: 87.2% - 98.5 %) and a specificity of 86% (95% CI: 67.3% -95.9 %) for the diagnosis of CL. On VL suspects the sensitivity was 92% (95% CI: 74.9 - 99.1%) and specificity of 100% (95% CI: 85.8-100%) in whole blood. For CL, LAMP is a sensitive tool for diagnosis and requires less equipment, time and expertise than alternative CL diagnostics. For VL, LAMP is sensitive using a minimally invasive sample as compared to the gold standard. The analytical specificity was 100%. Copyright © 2018 Adams et al.

Rapid and accurate detection of KRAS mutations in colorectal cancers using the isothermal-based optical sensor for companion diagnostics

PubMed Central

Koo, Bonhan; Lee, Tae Yoon; Lee, Jeong Hoon; Shin, Yong; Lim, Seok-Byung

2017-01-01

Although KRAS mutational status testing is becoming a companion diagnostic tool for managing patients with colorectal cancer (CRC), there are still several difficulties when analyzing KRAS mutations using the existing assays, particularly with regard to low sensitivity, its time-consuming, and the need for large instruments. We developed a rapid, sensitive, and specific mutation detection assay based on the bio-photonic sensor termed ISAD (isothermal solid-phase amplification/detection), and used it to analyze KRAS gene mutations in human clinical samples. To validate the ISAD-KRAS assay for use in clinical diagnostics, we examined for hotspot KRAS mutations (codon 12 and codon 13) in 70 CRC specimens using PCR and direct sequencing methods. In a serial dilution study, ISAD-KRAS could detect mutations in a sample containing only 1% of the mutant allele in a mixture of wild-type DNA, whereas both PCR and direct sequencing methods could detect mutations in a sample containing approximately 30% of mutant cells. The results of the ISAD-KRAS assay from 70 clinical samples matched those from PCR and direct sequencing, except in 5 cases, wherein ISAD-KRAS could detect mutations that were not detected by PCR and direct sequencing. We also found that the sensitivity and specificity of ISAD-KRAS were 100% within 30 min. The ISAD-KRAS assay provides a rapid, highly sensitive, and label-free method for KRAS mutation testing, and can serve as a robust and near patient testing approach for the rapid detection of patients most likely to respond to anti-EGFR drugs. PMID:29137388

An Innovative Field-Applicable Molecular Test to Diagnose Cutaneous Leishmania Viannia spp. Infections

PubMed Central

Saldarriaga, Omar A.; Castellanos-Gonzalez, Alejandro; Porrozzi, Renato; Baldeviano, Gerald C.; Lescano, Andrés G.; de Los Santos, Maxy B.; Fernandez, Olga L.; Saravia, Nancy G.; Costa, Erika; Melby, Peter C.; Travi, Bruno L.

2016-01-01

Cutaneous and mucosal leishmaniasis is widely distributed in Central and South America. Leishmania of the Viannia subgenus are the most frequent species infecting humans. L. (V.) braziliensis, L. (V.) panamensis are also responsible for metastatic mucosal leishmaniasis. Conventional or real time PCR is a more sensitive diagnostic test than microscopy, but the cost and requirement for infrastructure and trained personnel makes it impractical in most endemic regions. Primary health systems need a sensitive and specific point of care (POC) diagnostic tool. We developed a novel POC molecular diagnostic test for cutaneous leishmaniasis caused by Leishmania (Viannia) spp. Parasite DNA was amplified using isothermal Recombinase Polymerase Amplification (RPA) with primers and probes that targeted the kinetoplast DNA. The amplification product was detected by naked eye with a lateral flow (LF) immunochromatographic strip. The RPA-LF had an analytical sensitivity equivalent to 0.1 parasites per reaction. The test amplified the principal L. Viannia species from multiple countries: L. (V.) braziliensis (n = 33), L. (V.) guyanensis (n = 17), L. (V.) panamensis (n = 9). The less common L. (V.) lainsoni, L. (V.) shawi, and L. (V.) naiffi were also amplified. No amplification was observed in parasites of the L. (Leishmania) subgenus. In a small number of clinical samples (n = 13) we found 100% agreement between PCR and RPA-LF. The high analytical sensitivity and clinical validation indicate the test could improve the efficiency of diagnosis, especially in chronic lesions with submicroscopic parasite burdens. Field implementation of the RPA-LF test could contribute to management and control of cutaneous and mucosal leishmaniasis. PMID:27115155

Systematic review of fall risk screening tools for older patients in acute hospitals.

PubMed

Matarese, Maria; Ivziku, Dhurata; Bartolozzi, Francesco; Piredda, Michela; De Marinis, Maria Grazia

2015-06-01

To determine the most accurate fall risk screening tools for predicting falls among patients aged 65 years or older admitted to acute care hospitals. Falls represent a serious problem in older inpatients due to the potential physical, social, psychological and economic consequences. Older inpatients present with risk factors associated with age-related physiological and psychological changes as well as multiple morbidities. Thus, fall risk screening tools for older adults should include these specific risk factors. There are no published recommendations addressing what tools are appropriate for older hospitalized adults. Systematic review. MEDLINE, CINAHL and Cochrane electronic databases were searched between January 1981-April 2013. Only prospective validation studies reporting sensitivity and specificity values were included. Recommendations of the Cochrane Handbook of Diagnostic Test Accuracy Reviews have been followed. Three fall risk assessment tools were evaluated in seven articles. Due to the limited number of studies, meta-analysis was carried out only for the STRATIFY and Hendrich Fall Risk Model II. In the combined analysis, the Hendrich Fall Risk Model II demonstrated higher sensitivity than STRATIFY, while the STRATIFY showed higher specificity. In both tools, the Youden index showed low prognostic accuracy. The identified tools do not demonstrate predictive values as high as needed for identifying older inpatients at risk for falls. For this reason, no tool can be recommended for fall detection. More research is needed to evaluate fall risk screening tools for older inpatients. © 2014 John Wiley & Sons Ltd.

A case definition and photographic screening tool for the facial phenotype of fetal alcohol syndrome.

PubMed

Astley, S J; Clarren, S K

1996-07-01

The purpose of this study was to demonstrate that a quantitative, multivariate case definition of the fetal alcohol syndrome (FAS) facial phenotype could be derived from photographs of individuals with FAS and to demonstrate how this case definition and photographic approach could be used to develop efficient, accurate, and precise screening tools, diagnostic aids, and possibly surveillance tools. Frontal facial photographs of 42 subjects (from birth to 27 years of age) with FAS were matched to 84 subjects without FAS. The study population was randomly divided in half. Group 1 was used to identify the facial features that best differentiated individuals with and without FAS. Group 2 was used for cross validation. In group 1, stepwise discriminant analysis identified three facial features (reduced palpebral fissure length/inner canthal distance ratio, smooth philtrum, and thin upper lip) as the cluster of features that differentiated individuals with and without FAS in groups 1 and 2 with 100% accuracy. Sensitivity and specificity were unaffected by race, gender, and age. The phenotypic case definition derived from photographs accurately distinguished between individuals with and without FAS, demonstrating the potential of this approach for developing screening, diagnostic, and surveillance tools. Further evaluation of the validity and generalizability of this method will be needed.

Criterion and concurrent validity of Conners Adult ADHD Diagnostic Interview for DSM-IV (CAADID) Spanish version.

PubMed

Ramos-Quiroga, Josep Antoni; Bosch, Rosa; Richarte, Vanesa; Valero, Sergi; Gómez-Barros, Nuria; Nogueira, Mariana; Palomar, Gloria; Corrales, Montse; Sáez-Francàs, Naia; Corominas, Margarida; Real, Alberto; Vidal, Raquel; Chalita, Pablo J; Casas, Miguel

2012-01-01

Attention deficit hyperactivity disorder (ADHD) is a common neuropsychiatric disorder in adulthood. Its diagnosis requires a retrospective evaluation of ADHD symptoms in childhood, the continuity of these symptoms in adulthood, and a differential diagnosis. For these reasons, diagnosis of ADHD in adults is a complex process which needs effective diagnostic tools. To analyse the criterion validity of the CAADID semi-structured interview, Spanish version, and the concurrent validity compared with other ADHD severity scales. An observational case-control study was conducted on 691 patients with ADHD. They were out-patients treated in a program for adults with ADHD in a hospital. A sensitivity of 98.86%, specificity 67.68%, positive predictive value 90.77% and a negative predictive value 94.87% were observed. Diagnostic precision was 91.46%. The kappa index concordance between the clinical diagnostic interview and the CAADID was 0.88. Good concurrent validity was obtained, the CAADID correlated significantly with WURS scale (r=0.522, P<.01), ADHD Rating Scale (r=0.670, P<.0.1) and CAARS (self-rating version; r=0.656, P<.01 and observer-report r=0.514, P<.01). CAADID is a valid and useful tool for the diagnosis of ADHD in adults for clinical, as well as for research purposes. Copyright © 2012 SEP y SEPB. Published by Elsevier España, S.L. All rights reserved.

Discovery of putative salivary biomarkers for Sjögren's syndrome using high resolution mass spectrometry and bioinformatics.

PubMed

Zoukhri, Driss; Rawe, Ian; Singh, Mabi; Brown, Ashley; Kublin, Claire L; Dawson, Kevin; Haddon, William F; White, Earl L; Hanley, Kathleen M; Tusé, Daniel; Malyj, Wasyl; Papas, Athena

2012-03-01

The purpose of the current study was to determine if saliva contains biomarkers that can be used as diagnostic tools for Sjögren's syndrome (SjS). Twenty seven SjS patients and 27 age-matched healthy controls were recruited for these studies. Unstimulated glandular saliva was collected from the Wharton's duct using a suction device. Two µl of salvia were processed for mass spectrometry analyses on a prOTOF 2000 matrix-assisted laser desorption/ionization orthogonal time of flight (MALDI O-TOF) mass spectrometer. Raw data were analyzed using bioinformatic tools to identify biomarkers. MALDI O-TOF MS analyses of saliva samples were highly reproducible and the mass spectra generated were very rich in peptides and peptide fragments in the 750-7,500 Da range. Data analysis using bioinformatic tools resulted in several classification models being built and several biomarkers identified. One model based on 7 putative biomarkers yielded a sensitivity of 97.5%, specificity of 97.8% and an accuracy of 97.6%. One biomarker was present only in SjS samples and was identified as a proteolytic peptide originating from human basic salivary proline-rich protein 3 precursor. We conclude that salivary biomarkers detected by high-resolution mass spectrometry coupled with powerful bioinformatic tools offer the potential to serve as diagnostic/prognostic tools for SjS.

Utility of a brief assessment tool developed from the Dizziness Handicap Inventory to screen for Cervicogenic dizziness: A case control study.

PubMed

Reid, Susan A; Callister, Robin; Katekar, Michael G; Treleaven, Julia M

2017-08-01

Cervicogenic dizziness (CGD) is hard to diagnose as there is no objective test. Can a brief assessment tool be derived from the Dizziness Handicap Inventory (DHI) to assist in screening for CGD? Case-control study with split-sample analysis. 86 people with CGD and 86 people with general dizziness completed the DHI as part of the assessment of their dizziness. Descriptive statistics were used to assess how frequently each question on the DHI was answered 'yes' or 'sometimes' by participants with CGD and by participants with general dizziness. The questions that best discriminated between GCD and general dizziness were compiled into a brief assessment tool for CGD. Data from 80 participants (40 from each group) were used to generate a receiver operating characteristic (ROC) curve to establish a cut-off score for that brief assessment tool. Then, data from the remaining 92 participants were used to try to validate the diagnostic ability of the brief assessment tool using that cut-off score. Questions 1, 9 and 11 were the most discriminatory and were combined to form the brief assessment tool. The ROC curve indicated an optimal threshold of 9. The diagnostic ability of the brief assessment tool among the remaining 46 participants from each group was: sensitivity 77% (95% CI: 67 to 84), specificity 66% (56-75), positive likelihood ratio 2.28 (1.66-3.13), and negative likelihood ratio 0.35 (0.23-0.53). A brief assessment tool of three questions appears to be helpful in screening for CGD. Copyright © 2017. Published by Elsevier Ltd.

NEMOTAM: tangent and adjoint models for the ocean modelling platform NEMO

NASA Astrophysics Data System (ADS)

Vidard, A.; Bouttier, P.-A.; Vigilant, F.

2015-04-01

Tangent linear and adjoint models (TAMs) are efficient tools to analyse and to control dynamical systems such as NEMO. They can be involved in a large range of applications such as sensitivity analysis, parameter estimation or the computation of characteristic vectors. A TAM is also required by the 4D-Var algorithm, which is one of the major methods in data assimilation. This paper describes the development and the validation of the tangent linear and adjoint model for the NEMO ocean modelling platform (NEMOTAM). The diagnostic tools that are available alongside NEMOTAM are detailed and discussed, and several applications are also presented.

NEMOTAM: tangent and adjoint models for the ocean modelling platform NEMO

NASA Astrophysics Data System (ADS)

Vidard, A.; Bouttier, P.-A.; Vigilant, F.

2014-10-01

The tangent linear and adjoint model (TAM) are efficient tools to analyse and to control dynamical systems such as NEMO. They can be involved in a large range of applications such as sensitivity analysis, parameter estimation or the computation of characteristics vectors. TAM is also required by the 4-D-VAR algorithm which is one of the major method in Data Assimilation. This paper describes the development and the validation of the Tangent linear and Adjoint Model for the NEMO ocean modelling platform (NEMOTAM). The diagnostic tools that are available alongside NEMOTAM are detailed and discussed and several applications are also presented.

Evaluation of serological diagnostic tests for typhoid fever in Papua New Guinea using a composite reference standard.

PubMed

Siba, Valentine; Horwood, Paul F; Vanuga, Kilagi; Wapling, Johanna; Sehuko, Rebecca; Siba, Peter M; Greenhill, Andrew R

2012-11-01

Typhoid fever remains a major global health problem. A major impediment to improving outcomes is the lack of appropriate diagnostic tools, which have not significantly improved in low-income settings for 100 years. We evaluated two commercially available rapid diagnostic tests (Tubex and TyphiDot), a prototype (TyphiRapid TR-02), and the commonly used single-serum Widal test in a previously reported high-burden area of Papua New Guinea. Samples were collected from 530 outpatients with axillary temperatures of ≥37.5°C, and analysis was conducted on all malaria-negative samples (n = 500). A composite reference standard of blood culture and PCR was used, by which 47 participants (9.4%) were considered typhoid fever positive. The sensitivity and specificity of the Tubex (51.1% and 88.3%, respectively) and TyphiDot (70.0% and 80.1%, respectively) tests were not high enough to warrant their ongoing use in this setting; however, the sensitivity and specificity for the TR-02 prototype were promising (89.4% and 85.0%, respectively). An axillary temperature of ≥38.5°C correlated with typhoid fever (P = 0.014). With an appropriate diagnostic test, conducting typhoid fever diagnosis only on patients with high-grade fever could dramatically decrease the costs associated with diagnosis while having no detrimental impact on the ability to accurately diagnose the illness.

Comparing the diagnostic properties of skin scraping, adhesive tape, and dermoscopy in diagnosing scabies.

PubMed

Abdel-Latif, Azmy A; Elshahed, Ahmad R; Salama, Omar A; Elsaie, Mohamed L

2018-06-01

Scabies is a contagious skin infestation that mainly presents with itching at night and skin burrows that are visible to the naked eye. Diagnosing scabies with dermoscopy is still a matter of controversy. The aim of our study was to compare the diagnostic properties of adhesive tape, skin scraping, and dermoscopy in diagnosing scabies. One hundred patients with clinical presumptive diagnoses of scabies underwent skin scraping, adhesive tape testing, and dermoscopic examination. Each diagnostic procedure was performed on three different areas. Comparing the diagnostic properties of the three methods, the adhesive tape test was the most sensitive method for diagnosing scabies. Sixteen cases (16.0%) were definitely diagnosed as scabies using the adhesive tape test detecting the presence of mites or their eggs. Only 10 cases (10.0%) were definitely diagnosed as scabies using the skin scraping test detecting mites or their eggs. Dermoscopic examination suggested a diagnosis of scabies in 22 cases (22.0%), of which only 10 were definitely diagnosed as scabies by detecting mites using the adhesive tape test, skin scraping, or both. The diagnosis of scabies can only be confirmed by seeing mites. The adhesive tape test and skin scraping procedure have high specificity in diagnosing scabies, but their low sensitivity cannot exclude the possibility of scabies. Dermoscopy-guided tape testing can be a helpful tool for better diagnosis of scabies.

Bone Disease after Kidney Transplantation

PubMed Central

Bouquegneau, Antoine; Salam, Syrazah; Delanaye, Pierre; Eastell, Richard

2016-01-01

Bone and mineral disorders occur frequently in kidney transplant recipients and are associated with a high risk of fracture, morbidity, and mortality. There is a broad spectrum of often overlapping bone diseases seen after transplantation, including osteoporosis as well as persisting high– or low–turnover bone disease. The pathophysiology underlying bone disorders after transplantation results from a complex interplay of factors, including preexisting renal osteodystrophy and bone loss related to a variety of causes, such as immunosuppression and alterations in the parathyroid hormone-vitamin D-fibroblast growth factor 23 axis as well as changes in mineral metabolism. Management is complex, because noninvasive tools, such as imaging and bone biomarkers, do not have sufficient sensitivity and specificity to detect these abnormalities in bone structure and function, whereas bone biopsy is not a widely available diagnostic tool. In this review, we focus on recent data that highlight improvements in our understanding of the prevalence, pathophysiology, and diagnostic and therapeutic strategies of mineral and bone disorders in kidney transplant recipients. PMID:26912549

Electromigration techniques--a fast and economical tool for differentiation of similar strains of microorganisms.

PubMed

Horká, Marie; Horký, Jaroslav; Kubesová, Anna; Mazanec, Karel; Matousková, Hana; Slais, Karel

2010-07-01

The detection and identification of pathogens currently relies upon a very diverse range of techniques and skills, from traditional cultivation and taxonomic procedures to modern rapid and sensitive diagnostic methods. Real-time PCR is now exploited as a front line diagnostic screening tool in human, animal and plant health as well as bio-security. Nevertheless, new techniques for pathogen identification, particularly of unknown samples, are needed. In this study we propose the combination of electrophoresis-based procedures for the fast differentiation of microorganisms. The method feasibility is proved on the model of seven similar strains of Pseudomonas syringae pathovars from 37 sources, identified by gas chromatography of fatty acid methyl esters. The results from the routine laboratory were compared with results of the combination of the developed capillary and gel electrophoresis as well as mass spectrometry. According to our experiments appropriate combination of electromigration techniques appears to be useful for the fast and economical differentiation of unknown microorganisms.

eap Gene as novel target for specific identification of Staphylococcus aureus.

PubMed

Hussain, Muzaffar; von Eiff, Christof; Sinha, Bhanu; Joost, Insa; Herrmann, Mathias; Peters, Georg; Becker, Karsten

2008-02-01

The cell surface-associated extracellular adherence protein (Eap) mediates adherence of Staphylococcus aureus to host extracellular matrix components and inhibits inflammation, wound healing, and angiogenesis. A well-characterized collection of S. aureus and non-S. aureus staphylococcal isolates (n = 813) was tested for the presence of the Eap-encoding gene (eap) by PCR to investigate the use of the eap gene as a specific diagnostic tool for identification of S. aureus. Whereas all 597 S. aureus isolates were eap positive, this gene was not detectable in 216 non-S. aureus staphylococcal isolates comprising 47 different species and subspecies of coagulase-negative staphylococci and non-S. aureus coagulase-positive or coagulase-variable staphylococci. Furthermore, non-S. aureus isolates did not express Eap homologs, as verified on the transcriptional and protein levels. Based on these data, the sensitivity and specificity of the newly developed PCR targeting the eap gene were both 100%. Thus, the unique occurrence of Eap in S. aureus offers a promising tool particularly suitable for molecular diagnostics of this pathogen.

Noninvasive detection of intracerebral hemorrhage using near-infrared spectroscopy (NIRS)

NASA Astrophysics Data System (ADS)

Hennes, Hans-Juergen; Lott, Carsten; Windirsch, Michael; Hanley, Daniel F.; Boor, Stephan; Brambrink, Ansgar; Dick, Wolfgang

1998-01-01

Intracerebral Hemorrhage (IH) is an important cause of secondary brain injury in neurosurgical patients. Early identification and treatment improve neurologic outcome. We have tested Near Infrared Spectroscopy (NIRS) as an alternative noninvasive diagnostic tool compared to CT-Scans to detect IH. We prospectively studied 212 patients with neurologic symptoms associated with intracranial pathology before performing a CT-scan. NIRS signals indicated pathologies in 181 cases (sensitivity 0.96; specificity 0.29). In a subgroup of subdural hematomas NIRS detected 45 of 46 hematomas (sensitivity 0.96; specificity 0.79). Identification of intracerebral hemorrhage using NIRS has the potential to allow early treatment, thus possibly avoiding further injury.

Noninvasive detection of intracerebral hemorrhage using near-infrared spectroscopy (NIRS)

NASA Astrophysics Data System (ADS)

Hennes, Hans J.; Lott, C.; Windirsch, Michael; Hanley, Daniel F.; Boor, Stephan; Brambrink, Ansgar; Dick, Wolfgang

1997-12-01

Intracerebral Hemorrhage (IH) is an important cause of secondary brain injury in neurosurgical patients. Early identification and treatment improve neurologic outcome. We have tested Near Infrared Spectroscopy (NIRS) as an alternative noninvasive diagnostic tool compared to CT-Scans to detect IH. We prospectively studied 212 patients with neurologic symptoms associated with intracranial pathology before performing a CT-scan. NIRS signals indicated pathologies in 181 cases (sensitivity 0.96; specificity 0.29). In a subgroup of subdural hematomas NIRS detected 45 of 46 hematomas (sensitivity 0.96; specificity 0.79). Identification of intracerebral hemorrhage using NIRS has the potential to allow early treatment, thus possibly avoiding further injury.

Evaluating the Diagnostic Accuracy of Xpert MTB/RIF Assay in Pulmonary Tuberculosis

PubMed Central

Sharma, Surendra K; Kohli, Mikashmi; Yadav, Raj Narayan; Chaubey, Jigyasa; Bhasin, Dinkar; Sreenivas, Vishnubhatla; Sharma, Rohini; Singh, Binit K

2015-01-01

Pulmonary tuberculosis still remains a major communicable disease worldwide. In 2013, 9 million people developed TB and 1.5 million people died from the disease. India constitutes 24% of the total TB burden. Early detection of TB cases is the key to successful treatment and reduction of disease transmission. Xpert MTB/RIF, an automated cartridge-based molecular technique detects Mycobacterium tuberculosis and rifampicin resistance within two hours has been endorsed by WHO for rapid diagnosis of TB. Our study is the first study from India with a large sample size to evaluate the performance of Xpert MTB/RIF assay in PTB samples. The test showed an overall sensitivity and specificity of 95.7% (430/449) and 99.3% (984/990) respectively. In smear negative-culture positive cases, the test had a sensitivity of 77.7%. The sensitivity and specificity for detecting rifampicin resistance was 94.5% and 97.7% respectively with respect to culture as reference standard. However, after resolving the discrepant samples with gene sequencing, the sensitivity and specificity rose to 99.0% and 99.3% respectively. Hence, while solid culture still forms the foundation of TB diagnosis, Xpert MTB/RIF proposes to be a strong first line diagnostic tool for pulmonary TB cases. PMID:26496123

A statistical approach to detection of copy number variations in PCR-enriched targeted sequencing data.

PubMed

Demidov, German; Simakova, Tamara; Vnuchkova, Julia; Bragin, Anton

2016-10-22

Multiplex polymerase chain reaction (PCR) is a common enrichment technique for targeted massive parallel sequencing (MPS) protocols. MPS is widely used in biomedical research and clinical diagnostics as the fast and accurate tool for the detection of short genetic variations. However, identification of larger variations such as structure variants and copy number variations (CNV) is still being a challenge for targeted MPS. Some approaches and tools for structural variants detection were proposed, but they have limitations and often require datasets of certain type, size and expected number of amplicons affected by CNVs. In the paper, we describe novel algorithm for high-resolution germinal CNV detection in the PCR-enriched targeted sequencing data and present accompanying tool. We have developed a machine learning algorithm for the detection of large duplications and deletions in the targeted sequencing data generated with PCR-based enrichment step. We have performed verification studies and established the algorithm's sensitivity and specificity. We have compared developed tool with other available methods applicable for the described data and revealed its higher performance. We showed that our method has high specificity and sensitivity for high-resolution copy number detection in targeted sequencing data using large cohort of samples.

Developing the Thai Siriraj Psoriatic Arthritis Screening Tool and validating the Thai Psoriasis Epidemiology Screening Tool and the Early Arthritis for Psoriatic Patients questionnaire.

PubMed

Chiowchanwisawakit, Praveena; Wattanamongkolsil, Luksame; Srinonprasert, Varalak; Petcharat, Chonachan; Siriwanarangsun, Palanan; Katchamart, Wanruchada

2016-10-01

To validate the Thai language version of the Psoriasis Epidemiology Screening Tool (PEST) and the Early Arthritis for Psoriatic Patients Questionnaire (EARP), as well as also to develop a new tool for screening psoriatic arthritis (PsA) among psoriasis (Ps) patients. This was a cross-sectional study. Ps patients visiting the psoriasis clinic at Siriraj Hospital were recruited. They completed the EARP and PEST. Full musculoskeletal history, examination, and radiography were evaluated. PsA was diagnosed by a rheumatologist's evaluation and fulfillment of the classification criteria for psoriatic arthritis. Receiver operator characteristic (ROC) curves, sensitivity, and specificity were used to evaluate the performances of the tools. The Siriraj Psoriatic Arthritis Screening Tool (SiPAT) contained questions most relevant to peripheral arthritis, axial inflammation, and enthesitis, selected from multivariate analysis. Of a total of 159 patients, the prevalence of PsA was 78.6 %. The ROC curve analyses of Thai EARP, PEST, and SiPAT were 0.90 (95 % CI 0.84, 0.96), 0.85 (0.78, 0.92), and 0.89 (0.83, 0.95), respectively. The sensitivities of SiPAT, Thai EARP, and PEST were 91.0, 83.0, and 72.0 %, respectively, while the specificities were 69.0, 79.3, and 89.7 %, respectively. All screening questionnaires showed good diagnostic performances. SiPAT could be considered as a screening tool with its desirable properties: higher sensitivity and taking less time. Thai PEST and EARP could possibly be sequentially administered for people with a positive test from SiPAT to reduce the number of false positives.

Evaluation of whole genome sequencing and software tools for drug susceptibility testing of Mycobacterium tuberculosis.

PubMed

van Beek, J; Haanperä, M; Smit, P W; Mentula, S; Soini, H

2018-04-11

Culture-based assays are currently the reference standard for drug susceptibility testing for Mycobacterium tuberculosis. They provide good sensitivity and specificity but are time consuming. The objective of this study was to evaluate whether whole genome sequencing (WGS), combined with software tools for data analysis, can replace routine culture-based assays for drug susceptibility testing of M. tuberculosis. M. tuberculosis cultures sent to the Finnish mycobacterial reference laboratory in 2014 (n = 211) were phenotypically tested by Mycobacteria Growth Indicator Tube (MGIT) for first-line drug susceptibilities. WGS was performed for all isolates using the Illumina MiSeq system, and data were analysed using five software tools (PhyResSE, Mykrobe Predictor, TB Profiler, TGS-TB and KvarQ). Diagnostic time and reagent costs were estimated for both methods. The sensitivity of the five software tools to predict any resistance among strains was almost identical, ranging from 74% to 80%, and specificity was more than 95% for all software tools except for TGS-TB. The sensitivity and specificity to predict resistance to individual drugs varied considerably among the software tools. Reagent costs for MGIT and WGS were €26 and €143 per isolate respectively. Turnaround time for MGIT was 19 days (range 10-50 days) for first-line drugs, and turnaround time for WGS was estimated to be 5 days (range 3-7 days). WGS could be used as a prescreening assay for drug susceptibility testing with confirmation of resistant strains by MGIT. The functionality and ease of use of the software tools need to be improved. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Efficiency of Nested-PCR in Detecting Asymptomatic Cases toward Malaria Elimination Program in an Endemic Area of Iran.

PubMed

Turki, Habibollah; Raeisi, Ahmad; Malekzadeh, Kianoosh; Ghanbarnejad, Amin; Zoghi, Samaneh; Yeryan, Masoud; Abedi Nejad, Masoumeh; Mohseni, Fatemeh; Shekari, Mohammad

2015-01-01

The aim of this study was to detect low parasite and asymptomatic malaria infections by means of three malaria diagnostic tests, in a low transmission region of Minab district, Hormozgan Province, southern Iran. Blood samples of 200 healthy volunteers from Bagh-e-Malek area were evaluated using microscopic, rapid diagnostic tests (RDT) and nested-PCR to inspect malaria parasite. The results showed no Plasmodium parasite in subjects by means of microscopy and RDT. However, 3 P. vivax positive samples (1.5%) were discovered by Nested-PCR while microscopy and RDT missed the cases. Microscopy as the gold standard method and RDT correctly identified 98.5% of cases, and molecular analysis is sensitive and reliable, especially in the detection of "asymptomatic" infections for active case surveillance. Regarding the existence of asymptomatic malaria in endemic area of Hormozgan, Iran, nested-PCR could be considered as a sensitive tool to interrupt malaria transmission in the country, beside the microscopic and RDT methods.

Diagnostic imaging of blunt abdominal trauma in pediatric patients.

PubMed

Miele, Vittorio; Piccolo, Claudia Lucia; Trinci, Margherita; Galluzzo, Michele; Ianniello, Stefania; Brunese, Luca

2016-05-01

Trauma is a leading cause of morbidity and mortality in childhood, and blunt trauma accounts for 80-90 % of abdominal injuries. The mechanism of trauma is quite similar to that of the adults, but there are important physiologic differences between children and adults in this field, such as the smaller blood vessels and the high vasoconstrictive response, leading to the spreading of a non-operative management. The early imaging of children undergoing a low-energy trauma can be performed by CEUS, a valuable diagnostic tool to demonstrate solid organ injuries with almost the same sensitivity of CT scans; nevertheless, as for as urinary tract injuries, MDCT remains still the technique of choice, because of its high sensitivity and accuracy, helping to discriminate between an intra-peritoneal form a retroperitoneal urinary leakage, requiring two different managements. The liver is the most common organ injured in blunt abdominal trauma followed by the spleen. Renal, pancreatic, and bowel injuries are quite rare. In this review we present various imaging findings of blunt abdominal trauma in children.

Assessment of Myometrial Invasion in Premenopausal Grade 1 Endometrial Carcinoma: Is Magnetic Resonance Imaging a Reliable Tool in Selecting Patients for Fertility-Preserving Therapy?

PubMed

Sakane, Makoto; Hori, Masatoshi; Onishi, Hiromitsu; Tsuboyama, Takahiro; Ota, Takashi; Tatsumi, Mitsuaki; Ueda, Yutaka; Kimura, Toshihiro; Kimura, Tadashi; Tomiyama, Noriyuki

The aim of this study was to evaluate the diagnostic ability of magnetic resonance imaging (MRI) in premenopausal women with G1 endometrial carcinoma. Twenty-six patients underwent T2W, diffusion weighted, and dynamic contrast-enhanced 3-T MRI. The degree of myometrial invasion was pathologically classified into no invasion, shallow (3 mm or less), and more. Two radiologists assessed myometrial invasion on MRI. Diagnostic accuracy, sensitivity, specificity, positive and negative predictive values, AUC, and interobserver agreement were analyzed. For assessing myometrial invasion, mean accuracy, sensitivity, specificity, positive predictive values, negative predictive values, and AUC, respectively, were as follows: 63%, 42%, 85%, 79%, 47%, and 0.75. Mean interobserver agreement was fair (k = 0.36). Shallow invasions were underestimated as no invasion on MRI in all 6 cases. Magnetic resonance imaging produced false-negative result on half of patients. The misjudgments tended to happen in patients with shallow invasion.

Efficient genome-wide association in biobanks using topic modeling identifies multiple novel disease loci.

PubMed

McCoy, Thomas H; Castro, Victor M; Snapper, Leslie A; Hart, Kamber L; Perlis, Roy H

2017-08-31

Biobanks and national registries represent a powerful tool for genomic discovery, but rely on diagnostic codes that may be unreliable and fail to capture the relationship between related diagnoses. We developed an efficient means of conducting genome-wide association studies using combinations of diagnostic codes from electronic health records (EHR) for 10845 participants in a biobanking program at two large academic medical centers. Specifically, we applied latent Dirichilet allocation to fit 50 disease topics based on diagnostic codes, then conducted genome-wide common-variant association for each topic. In sensitivity analysis, these results were contrasted with those obtained from traditional single-diagnosis phenome-wide association analysis, as well as those in which only a subset of diagnostic codes are included per topic. In meta-analysis across three biobank cohorts, we identified 23 disease-associated loci with p<1e-15, including previously associated autoimmune disease loci. In all cases, observed significant associations were of greater magnitude than for single phenome-wide diagnostic codes, and incorporation of less strongly-loading diagnostic codes enhanced association. This strategy provides a more efficient means of phenome-wide association in biobanks with coded clinical data.

Efficient Genome-wide Association in Biobanks Using Topic Modeling Identifies Multiple Novel Disease Loci

PubMed Central

McCoy, Thomas H; Castro, Victor M; Snapper, Leslie A; Hart, Kamber L; Perlis, Roy H

2017-01-01

Biobanks and national registries represent a powerful tool for genomic discovery, but rely on diagnostic codes that can be unreliable and fail to capture relationships between related diagnoses. We developed an efficient means of conducting genome-wide association studies using combinations of diagnostic codes from electronic health records for 10,845 participants in a biobanking program at two large academic medical centers. Specifically, we applied latent Dirichilet allocation to fit 50 disease topics based on diagnostic codes, then conducted a genome-wide common-variant association for each topic. In sensitivity analysis, these results were contrasted with those obtained from traditional single-diagnosis phenome-wide association analysis, as well as those in which only a subset of diagnostic codes were included per topic. In meta-analysis across three biobank cohorts, we identified 23 disease-associated loci with p < 1e-15, including previously associated autoimmune disease loci. In all cases, observed significant associations were of greater magnitude than single phenome-wide diagnostic codes, and incorporation of less strongly loading diagnostic codes enhanced association. This strategy provides a more efficient means of identifying phenome-wide associations in biobanks with coded clinical data. PMID:28861588

Multivariate Analysis As a Support for Diagnostic Flowcharts in Allergic Bronchopulmonary Aspergillosis: A Proof-of-Concept Study.

PubMed

Vitte, Joana; Ranque, Stéphane; Carsin, Ania; Gomez, Carine; Romain, Thomas; Cassagne, Carole; Gouitaa, Marion; Baravalle-Einaudi, Mélisande; Bel, Nathalie Stremler-Le; Reynaud-Gaubert, Martine; Dubus, Jean-Christophe; Mège, Jean-Louis; Gaudart, Jean

2017-01-01

Molecular-based allergy diagnosis yields multiple biomarker datasets. The classical diagnostic score for allergic bronchopulmonary aspergillosis (ABPA), a severe disease usually occurring in asthmatic patients and people with cystic fibrosis, comprises succinct immunological criteria formulated in 1977: total IgE, anti- Aspergillus fumigatus ( Af ) IgE, anti- Af "precipitins," and anti- Af IgG. Progress achieved over the last four decades led to multiple IgE and IgG(4) Af biomarkers available with quantitative, standardized, molecular-level reports. These newly available biomarkers have not been included in the current diagnostic criteria, either individually or in algorithms, despite persistent underdiagnosis of ABPA. Large numbers of individual biomarkers may hinder their use in clinical practice. Conversely, multivariate analysis using new tools may bring about a better chance of less diagnostic mistakes. We report here a proof-of-concept work consisting of a three-step multivariate analysis of Af IgE, IgG, and IgG4 biomarkers through a combination of principal component analysis, hierarchical ascendant classification, and classification and regression tree multivariate analysis. The resulting diagnostic algorithms might show the way for novel criteria and improved diagnostic efficiency in Af -sensitized patients at risk for ABPA.

Diagnostic accuracy of quantitative real-time PCR assay versus clinical and Gram stain identification of bacterial vaginosis.

PubMed

Menard, J-P; Mazouni, C; Fenollar, F; Raoult, D; Boubli, L; Bretelle, F

2010-12-01

The purpose of this investigation was to determine the diagnostic accuracy of quantitative real-time polymerase chain reaction (PCR) assay in diagnosing bacterial vaginosis versus the standard methods, the Amsel criteria and the Nugent score. The Amsel criteria, the Nugent score, and results from the molecular tool were obtained independently from vaginal samples of 163 pregnant women who reported abnormal vaginal symptoms before 20 weeks gestation. To determine the performance of the molecular tool, we calculated the kappa value, sensitivity, specificity, and positive and negative predictive values. Either or both of the Amsel criteria (≥3 criteria) and the Nugent score (score ≥7) indicated that 25 women (15%) had bacterial vaginosis, and the remaining 138 women did not. DNA levels of Gardnerella vaginalis or Atopobium vaginae exceeded 10(9) copies/mL or 10(8) copies/mL, respectively, in 34 (21%) of the 163 samples. Complete agreement between both reference methods and high concentrations of G. vaginalis and A. vaginae was found in 94.5% of women (154/163 samples, kappa value = 0.81, 95% confidence interval 0.70-0.81). The nine samples with discordant results were categorized as intermediate flora by the Nugent score. The molecular tool predicted bacterial vaginosis with a sensitivity of 100%, a specificity of 93%, a positive predictive value of 73%, and a negative predictive value of 100%. The quantitative real-time PCR assay shows excellent agreement with the results of both reference methods for the diagnosis of bacterial vaginosis.

Bioelectronic Sensors and Devices

NASA Astrophysics Data System (ADS)

Reed, Mark

Nanoscale electronic devices have recently enabled the ability to controllably probe biological systems, from the molecular to the cellular level, opening up new applications and understanding of biological function and response. This talk reviews some of the advances in the field, ranging from diagnostic and therapeutic applications, to cellular manipulation and response, to the emulation of biological response. In diagnostics, integrated nanodevice biosensors compatible with CMOS technology have achieved unprecedented sensitivity, enabling a wide range of label-free biochemical and macromolecule sensing applications down to femtomolar concentrations. These systems have demonstrated integrated assays of biomarkers at clinically important concentrations for both diagnostics and as a quantitative tool for drug design and discovery. Cellular level response can also be observed, including immune response function and dynamics. Finally, the field is beginning to create devices that emulate function, and the demonstration of a solid state artificial ion channel will be discussed.

Biosensors-on-chip: a topical review

NASA Astrophysics Data System (ADS)

Chen, Sensen; Shamsi, Mohtashim H.

2017-08-01

This review will examine the integration of two fields that are currently at the forefront of science, i.e. biosensors and microfluidics. As a lab-on-a-chip (LOC) technology, microfluidics has been enriched by the integration of various detection tools for analyte detection and quantitation. The application of such microfluidic platforms is greatly increased in the area of biosensors geared towards point-of-care diagnostics. Together, the merger of microfluidics and biosensors has generated miniaturized devices for sample processing and sensitive detection with quantitation. We believe that microfluidic biosensors (biosensors-on-chip) are essential for developing robust and cost effective point-of-care diagnostics. This review is relevant to a variety of disciplines, such as medical science, clinical diagnostics, LOC technologies including MEMs/NEMs, and analytical science. Specifically, this review will appeal to scientists working in the two overlapping fields of biosensors and microfluidics, and will also help new scientists to find their directions in developing point-of-care devices.

Early Diagnosis of Breast Cancer.

PubMed

Wang, Lulu

2017-07-05

Early-stage cancer detection could reduce breast cancer death rates significantly in the long-term. The most critical point for best prognosis is to identify early-stage cancer cells. Investigators have studied many breast diagnostic approaches, including mammography, magnetic resonance imaging, ultrasound, computerized tomography, positron emission tomography and biopsy. However, these techniques have some limitations such as being expensive, time consuming and not suitable for young women. Developing a high-sensitive and rapid early-stage breast cancer diagnostic method is urgent. In recent years, investigators have paid their attention in the development of biosensors to detect breast cancer using different biomarkers. Apart from biosensors and biomarkers, microwave imaging techniques have also been intensely studied as a promising diagnostic tool for rapid and cost-effective early-stage breast cancer detection. This paper aims to provide an overview on recent important achievements in breast screening methods (particularly on microwave imaging) and breast biomarkers along with biosensors for rapidly diagnosing breast cancer.

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.

The Ritvo Autism Asperger Diagnostic Scale-Revised (RAADS-R): a scale to assist the diagnosis of Autism Spectrum Disorder in adults: an international validation study.

PubMed

Ritvo, Riva Ariella; Ritvo, Edward R; Guthrie, Donald; Ritvo, Max J; Hufnagel, Demetra H; McMahon, William; Tonge, Bruce; Mataix-Cols, David; Jassi, Amita; Attwood, Tony; Eloff, Johann

2011-08-01

The Ritvo Autism Asperger Diagnostic Scale-Revised (RAADS-R) is a valid and reliable instrument to assist the diagnosis of adults with Autism Spectrum Disorders (ASD). The 80-question scale was administered to 779 subjects (201 ASD and 578 comparisons). All ASD subjects met inclusion criteria: DSM-IV-TR, ADI/ADOS diagnoses and standardized IQ testing. Mean scores for each of the questions and total mean ASD vs. the comparison groups' scores were significantly different (p < .0001). Concurrent validity with Constantino Social Responsiveness Scale-Adult = 95.59%. Sensitivity = 97%, specificity = 100%, test-retest reliability r = .987. Cronbach alpha coefficients for the subscales and 4 derived factors were good. We conclude that the RAADS-R is a useful adjunct diagnostic tool for adults with ASD.

Rapid bacterial diagnostics via surface enhanced Raman microscopy.

PubMed

Premasiri, W R; Sauer-Budge, A F; Lee, J C; Klapperich, C M; Ziegler, L D

2012-06-01

There is a continuing need to develop new techniques for the rapid and specific identification of bacterial pathogens in human body fluids especially given the increasing prevalence of drug resistant strains. Efforts to develop a surface enhanced Raman spectroscopy (SERS) based approach, which encompasses sample preparation, SERS substrates, portable Raman microscopy instrumentation and novel identification software, are described. The progress made in each of these areas in our laboratory is summarized and illustrated by a spiked infectious sample for urinary tract infection (UTI) diagnostics. SERS bacterial spectra exhibit both enhanced sensitivity and specificity allowing the development of an easy to use, portable, optical platform for pathogen detection and identification. SERS of bacterial cells is shown to offer not only reproducible molecular spectroscopic signatures for analytical applications in clinical diagnostics, but also is a new tool for studying biochemical activity in real time at the outer layers of these organisms.

Utility of the PHQ-9 to identify major depressive disorder in adult patients in Spanish primary care centres.

PubMed

Muñoz-Navarro, Roger; Cano-Vindel, Antonio; Medrano, Leonardo Adrián; Schmitz, Florian; Ruiz-Rodríguez, Paloma; Abellán-Maeso, Carmen; Font-Payeras, Maria Antonia; Hermosilla-Pasamar, Ana María

2017-08-09

The prevalence of major depressive disorder (MDD) in Spanish primary care (PC) centres is high. However, MDD is frequently underdiagnosed and consequently only some patients receive the appropriate treatment. The present study aims to determine the utility of the Patient Health Questionnaire-9 (PHQ-9) to identify MDD in a subset of PC patients participating in the large PsicAP study. A total of 178 patients completed the full PHQ test, including the depression module (PHQ-9). Also, a Spanish version of the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) was implemented by clinical psychologists that were blinded to the PHQ-9 results. We evaluated the psychometric properties of the PHQ-9 as a screening tool as compared to the SCID-I as a reference standard. The psychometric properties of the PHQ-9 for a cut-off value of 10 points were as follows: sensitivity, 0.95; specificity, 0.67. Using a cut-off of 12 points, the values were: sensitivity, 0.84; specificity, 0.78. Finally, using the diagnostic algorithm for depression (DSM-IV criteria), the sensitivity was 0.88 and the specificity 0.80. As a screening instrument, the PHQ-9 performed better with a cut-off value of 12 versus the standard cut-off of 10. However, the best psychometric properties were obtained with the DSM-IV diagnostic algorithm for depression. These findings indicate that the PHQ-9 is a highly satisfactory tool that can be used for screening MDD in the PC setting. Current Controlled Trials ISRCTN58437086 . Registered 20 May 2013.

Asking For Help is Helpful: Validation of a Brief Lifestyle and Mood Assessment Tool in Primary Health Care

PubMed Central

Goodyear-Smith, Felicity; Arroll, Bruce; Coupe, Nicole

2009-01-01

PURPOSE The short, validated, self-administered, Case-finding and Help Assessment Tool (CHAT) for lifestyle and mental health assessment of adult patients in primary health care addresses inactivity, tobacco use, alcohol and other drug misuse, problem gambling, depression, anxiety and stress, abuse, and anger problems. For each issue patients are asked whether they would like help, either during the consultation or at a later date. This study aims to assess the value of the help question. METHODS Validation of the CHAT was conducted according to the STAndards for Reporting of Diagnostic accuracy studies statement for diagnostic tests. The setting was Auckland primary care practices with populations ranging from socioeconomically advantaged to deprived. Participants were 755 consecutive primary care patients who completed the CHAT plus the help question and reference standards. Sensitivity, specificity, and likelihood ratios with and without the addition of help the question were calculated. RESULTS Sensitivity ranged from 80% to 98% for the more-common conditions (depression, nicotine dependency, anxiety, problematic drinking). For each condition, specificity increased with the addition of the help question: depression increased from 73% to 98%; anxiety 77% to 99%; drinking 85% to 99%; verbal anger 92% to 99%; verbal abuse 97% to 99%; problematic drinking and gambling 98% to 99%. CONCLUSIONS The help question increased specificity without compromising sensitivity and reduced false positives, thereby increasing the positive predictive value. It allowed patients with comorbidities to prioritize issues they wished to address, indicate their readiness to change, promote self-determination, and give the clinician an indication of which topics to pursue. PMID:19433841

Validation of a basic neurosonology laboratory for detecting cervical carotid artery stenosis.

PubMed

de la Cruz Cosme, C; Dawid Milner, M S; Ojeda Burgos, G; Gallardo Tur, A; Márquez Martínez, M; Segura, T

2017-03-24

Most of the cases of ischaemic stroke in our setting are of atherothrombotic origin. Detecting intracranial and cervical carotid artery stenosis in patients with ischaemic stroke is therefore essential. Ultrasonography has become the tool of choice for diagnosing carotid artery stenosis because it is both readily accessibility and reliable. However, use of this technique must be validated in each laboratory. The purpose of this study is to validate Doppler ultrasound in our laboratory as a means of detecting severe carotid artery stenosis. We conducted an observational descriptive study to evaluate diagnostic tests. The results from transcranial and cervical carotid Doppler ultrasound scans conducted by neurologists were compared to those from carotid duplex scans performed by radiologists in patients diagnosed with stroke. Arteriography was considered the gold standard (MR angiography, CT angiography, or conventional arteriography). Our sample included 228 patients. Transcranial and cervical carotid Doppler ultrasound showed a sensitivity of 95% and specificity of 100% for detection of carotid artery stenosis > 70%, whereas carotid duplex displayed a sensitivity of 87% and a specificity of 94%. Transcranial carotid Doppler ultrasound achieved a sensitivity of 78% and a specificity of 98% for detection of intracranial stenosis. Doppler ultrasound in our neurosonology laboratory was found to be a useful diagnostic tool for detecting cervical carotid artery stenosis and demonstrated superiority to carotid duplex despite the lack of B-mode. Furthermore, this technique was found to be useful for detecting intracranial stenosis. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Consequences of Base Time for Redundant Signals Experiments

PubMed Central

Townsend, James T.; Honey, Christopher

2007-01-01

We report analytical and computational investigations into the effects of base time on the diagnosticity of two popular theoretical tools in the redundant signals literature: (1) the race model inequality and (2) the capacity coefficient. We show analytically and without distributional assumptions that the presence of base time decreases the sensitivity of both of these measures to model violations. We further use simulations to investigate the statistical power model selection tools based on the race model inequality, both with and without base time. Base time decreases statistical power, and biases the race model test toward conservatism. The magnitude of this biasing effect increases as we increase the proportion of total reaction time variance contributed by base time. We marshal empirical evidence to suggest that the proportion of reaction time variance contributed by base time is relatively small, and that the effects of base time on the diagnosticity of our model-selection tools are therefore likely to be minor. However, uncertainty remains concerning the magnitude and even the definition of base time. Experimentalists should continue to be alert to situations in which base time may contribute a large proportion of the total reaction time variance. PMID:18670591

Diagnostic Tools for Acute Anterior Cruciate Ligament Injury: GNRB, Lachman Test, and Telos.

PubMed

Ryu, Seung Min; Na, Ho Dong; Shon, Oog Jin

2018-06-01

The purpose of this study is to compare the accuracy of the GNRB arthrometer (Genourob), Lachman test, and Telos device (GmbH) in acute anterior cruciate ligament (ACL) injuries and to evaluate the accuracy of each diagnostic tool according to the length of time from injury to examination. From September 2015 to September 2016, 40 cases of complete ACL rupture were reviewed. We divided the time from injury to examination into three periods of 10 days each and analyzed the diagnostic tools according to the time frame. An analysis of the area under the curve (AUC) of a receiver operating characteristic curve showed that all diagnostic tools were fairly informative. The GNRB showed a higher AUC than other diagnostic tools. In 10 cases assessed within 10 days after injury, the GNRB showed statistically significant side-to-side difference in laxity (p＜0.001), whereas the Telos test and Lachman test did not show significantly different laxity (p=0.541 and p=0.413, respectively). All diagnostic values of the GNRB were better than other diagnostic tools in acute ACL injuries. The GNRB was more effective in acute ACL injuries examined within 10 days of injury. The GNRB arthrometer can be a useful diagnostic tool for acute ACL injuries.

Serial combination of non-invasive tools improves the diagnostic accuracy of severe liver fibrosis in patients with NAFLD.

PubMed

Petta, S; Wong, V W-S; Cammà, C; Hiriart, J-B; Wong, G L-H; Vergniol, J; Chan, A W-H; Di Marco, V; Merrouche, W; Chan, H L-Y; Marra, F; Le-Bail, B; Arena, U; Craxì, A; de Ledinghen, V

2017-09-01

The accuracy of available non-invasive tools for staging severe fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) is still limited. To assess the diagnostic performance of paired or serial combination of non-invasive tools in NAFLD patients. We analysed data from 741 patients with a histological diagnosis of NAFLD. The GGT/PLT, APRI, AST/ALT, BARD, FIB-4, and NAFLD Fibrosis Score (NFS) scores were calculated according to published algorithms. Liver stiffness measurement (LSM) was performed by FibroScan. LSM, NFS and FIB-4 were the best non-invasive tools for staging F3-F4 fibrosis (AUC 0.863, 0.774, and 0.792, respectively), with LSM having the highest sensitivity (90%), and the highest NPV (94%), and NFS and FIB-4 the highest specificity (97% and 93%, respectively), and the highest PPV (73% and 79%, respectively). The paired combination of LSM or NFS with FIB-4 strongly reduced the likelihood of wrongly classified patients (ranging from 2.7% to 2.6%), at the price of a high uncertainty area (ranging from 54.1% to 58.2%), and of a low overall accuracy (ranging from 43% to 39.1%). The serial combination with the second test used in patients in the grey area of the first test and in those with high LSM values (>9.6 KPa) or low NFS or FIB-4 values (<-1.455 and <1.30, respectively) overall increased the diagnostic performance generating an accuracy ranging from 69.8% to 70.1%, an uncertainty area ranging from 18.9% to 20.4% and a rate of wrong classification ranging from 9.2% to 11.3%. The serial combination of LSM with FIB-4/NFS has a good diagnostic accuracy for the non-invasive diagnosis of severe fibrosis in NAFLD. © 2017 John Wiley & Sons Ltd.

A Comparison of Variant Calling Pipelines Using Genome in a Bottle as a Reference

PubMed Central

2015-01-01

High-throughput sequencing, especially of exomes, is a popular diagnostic tool, but it is difficult to determine which tools are the best at analyzing this data. In this study, we use the NIST Genome in a Bottle results as a novel resource for validation of our exome analysis pipeline. We use six different aligners and five different variant callers to determine which pipeline, of the 30 total, performs the best on a human exome that was used to help generate the list of variants detected by the Genome in a Bottle Consortium. Of these 30 pipelines, we found that Novoalign in conjunction with GATK UnifiedGenotyper exhibited the highest sensitivity while maintaining a low number of false positives for SNVs. However, it is apparent that indels are still difficult for any pipeline to handle with none of the tools achieving an average sensitivity higher than 33% or a Positive Predictive Value (PPV) higher than 53%. Lastly, as expected, it was found that aligners can play as vital a role in variant detection as variant callers themselves. PMID:26539496

Acoustic sensors as a biophysical tool for probing cell attachment and cell/surface interactions.

PubMed

Saitakis, Michael; Gizeli, Electra

2012-02-01

Acoustic biosensors offer the possibility to analyse cell attachment and spreading. This is due to the offered speed of detection, the real-time non-invasive approach and their high sensitivity not only to mass coupling, but also to viscoelastic changes occurring close to the sensor surface. Quartz crystal microbalance (QCM) and surface acoustic wave (Love-wave) systems have been used to monitor the adhesion of animal cells to various surfaces and record the behaviour of cell layers under various conditions. The sensors detect cells mostly via their sensitivity in viscoelasticity and mechanical properties. Particularly, the QCM sensor detects cytoskeletal rearrangements caused by specific drugs affecting either actin microfilaments or microtubules. The Love-wave sensor directly measures cell/substrate bonds via acoustic damping and provides 2D kinetic and affinity parameters. Other studies have applied the QCM sensor as a diagnostic tool for leukaemia and, potentially, for chemotherapeutic agents. Acoustic sensors have also been used in the evaluation of the cytocompatibility of artificial surfaces and, in general, they have the potential to become powerful tools for even more diverse cellular analysis.

Ultrasound as a monitoring tool for cystic echinococcosis in sheep.

PubMed

Dore, F; Varcasia, A; Pipia, A P; Sanna, G; Pinna Parpaglia, M L; Corda, A; Romig, T; Scala, A

2014-06-16

An ultrasound-based survey for cystic echinococcosis (CE) in sheep was carried out in Sardinia in 2012. The study was done on three farms (A, B, C) which had been pre-selected for different CE prevalence levels (A: >80%, B: 50-80%, C: <50%). In total, 129 sheep were examined on the farms using portable ultrasound equipment (A: n=51, B: n=30, C: n=48). Within a period of 20 days after ultrasound examination, all sheep were slaughtered and underwent a parasitological post-mortem examination for cysts in the liver and lungs. With post-mortem as gold standard, ultrasonography gave a test sensitivity of 88.7% and a specificity of 75.9%, while the positive and negative predictive values were 81.8% and 84.6%, respectively. When only sheep with fertile cysts were considered, the sensitivity of the test increased to 100%. We conclude that the ultrasound examination of the liver in sheep - using state-of-the-art technology - is a sensitive and specific diagnostic tool, which is cost-effective, highly appropriate for field use and requires only moderate time (no shaving required). The method can also be applied to other livestock species and will be useful tool in epidemiological studies, monitoring schemes and vaccination/control trials. Copyright © 2014 Elsevier B.V. All rights reserved.

Usefulness of an inexpensive, Paracheck test in detecting asymptomatic infectious reservoir of plasmodium falciparum during dry season in an inaccessible terrain in central India.

PubMed

Singh, N; Saxena, A; Sharma, V P

2002-10-01

The performance of a new indigenous rapid diagnostic test, Paracheck Pf was evaluated in detection of Plasmodium falciparum in asymptomatic children in remote forest villages of Mandla district, central India to determine the lower limits of sensitivity and specificity of rapid test. A finger prick blood sample was collected to prepare blood smear and for testing with the Paracheck test. The blood smears were read by an experienced technician blinded to the Paracheck results. The figures for specificity, sensitivity, accuracy and predictive values were calculated using microscopy as gold standard. The new diagnostic test had a sensitivity of 94% and a specificity of 89%. The positive and negative predictive values were 71% and 98%, respectively. The J -index was 0.83%. The rapid test was found to be very easy to perform and the result could be read reliably by field workers. The field evaluation with this new inexpensive test, ($0.65/test) indicates that it could be used as an epidemiological tool in the management of malaria particularly in areas where microscopy is not operationally feasible to attain the goal of the roll back malaria initiative.

Diagnostic Ability of Wide-field Retinal Nerve Fiber Layer Maps Using Swept-Source Optical Coherence Tomography for Detection of Preperimetric and Early Perimetric Glaucoma.

PubMed

Lee, Won June; Na, Kyeong Ik; Kim, Young Kook; Jeoung, Jin Wook; Park, Ki Ho

2017-06-01

To evaluate the diagnostic ability of wide-field retinal nerve fiber layer (RNFL) maps with swept-source optical coherence tomography (SS-OCT) for detection of preperimetric (PPG) and early perimetric glaucoma (EG). One hundred eighty-four eyes, including 67 healthy eyes, 43 eyes with PPG, and 74 eyes with EG, were analyzed. Patients underwent a comprehensive ocular examination including red-free RNFL photography, visual field testing and wide-field SS-OCT scanning (DRI-OCT-1 Atlantis; Topcon, Tokyo, Japan). SS-OCT provides a wide-field RNFL thickness map and a SuperPixel map, which are composed of the RNFL deviation map of the peripapillary area and the deviation map of the composition of the ganglion cell layer with the inner plexiform layer and RNFL (GC-IPL+RNFL) in the macular area. The ability to discriminate PPG and EG from healthy eyes was assessed using sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) for all parameters and criteria provided by the wide-field SS-OCT scan. The wide-field RNFL thickness map using SS-OCT showed the highest sensitivity of PPG-diagnostic and EG-diagnostic performance compared with the other SS-OCT criteria based on the internal normative base (93.0 and 97.3%, respectively). Among the SS-OCT continuous parameters, the RFNL thickness of the 7 clock-hour, inferior and inferotemporal macular ganglion cell analyses showed the largest AUC of PPG-diagnostic and EG-diagnostic performance (AUC=0.809 to 0.865). The wide-field RNFL thickness map using SS-OCT performed well in distinguishing eyes with PPG and EG from healthy eyes. In the clinical setting, wide-field RNFL maps of SS-OCT can be useful tools for detection of early-stage glaucoma.

Evidence assessing the diagnostic performance of medical smartphone apps: a systematic review and exploratory meta-analysis.

PubMed

Buechi, Rahel; Faes, Livia; Bachmann, Lucas M; Thiel, Michael A; Bodmer, Nicolas S; Schmid, Martin K; Job, Oliver; Lienhard, Kenny R

2017-12-14

The number of mobile applications addressing health topics is increasing. Whether these apps underwent scientific evaluation is unclear. We comprehensively assessed papers investigating the diagnostic value of available diagnostic health applications using inbuilt smartphone sensors. Systematic Review-MEDLINE, Scopus, Web of Science inclusive Medical Informatics and Business Source Premier (by citation of reference) were searched from inception until 15 December 2016. Checking of reference lists of review articles and of included articles complemented electronic searches. We included all studies investigating a health application that used inbuilt sensors of a smartphone for diagnosis of disease. The methodological quality of 11 studies used in an exploratory meta-analysis was assessed with the Quality Assessment of Diagnostic Accuracy Studies 2 tool and the reporting quality with the 'STAndards for the Reporting of Diagnostic accuracy studies' (STARD) statement. Sensitivity and specificity of studies reporting two-by-two tables were calculated and summarised. We screened 3296 references for eligibility. Eleven studies, most of them assessing melanoma screening apps, reported 17 two-by-two tables. Quality assessment revealed high risk of bias in all studies. Included papers studied 1048 subjects (758 with the target conditions and 290 healthy volunteers). Overall, the summary estimate for sensitivity was 0.82 (95 % CI 0.56 to 0.94) and 0.89 (95 %CI 0.70 to 0.97) for specificity. The diagnostic evidence of available health apps on Apple's and Google's app stores is scarce. Consumers and healthcare professionals should be aware of this when using or recommending them. 42016033049. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Diagnostic accuracy, risk assessment, and cost-effectiveness of component-resolved diagnostics for food allergy: A systematic review.

PubMed

Flores Kim, J; McCleary, N; Nwaru, B I; Stoddart, A; Sheikh, A

2018-01-10

Component-resolved diagnostics (CRD) are promising tools for diagnosing food allergy, offering the potential to determine specific phenotypes and to develop patient-tailored risk profiles. Nevertheless, the diagnostic accuracy of these tests varies across studies; thus, their clinical utility remains unclear. Therefore, we synthesized the evidence from studies investigating the diagnostic accuracy, risk assessment ability, and cost-effectiveness of CRD for food allergy. We systematically searched 10 electronic databases and four clinical trial registries for studies published from January 2000 to February 2017. The quality of included studies was assessed using QUADAS-2. Due to heterogeneity, we narratively synthesized the evidence. Eleven studies met inclusion criteria, altogether recruiting 1098 participants. The food allergies investigated were cow's milk, hen's egg, peanut, hazelnut, and shrimp. The components with the highest diagnostic accuracy for each allergen, along with their sensitivity-specificity pairs, were as follows: Bos d 4 for cow's milk (62.0% and 87.5%), Gal d 1 for hen's egg (84.2% and 89.8% for heated egg, and 60.6% and 97.1% for raw egg), Ara h 6 for peanut (94.9% and 95.1%), Cor a 14 for hazelnut (100% and 93.8%), and Lit v 1 for shrimp (82.8% and 56.3%) allergy. Selected components of cow's milk, hen's egg, peanut, hazelnut, and shrimp allergen showed high specificity, but lower sensitivity. However, few studies exist for each component, and studies vary widely regarding the cutoff values used, making it challenging to synthesize findings across studies. Further research is needed to determine clinically appropriate cutoff values, risk assessment abilities, and cost-effectiveness of CRD approaches. © 2018 The Authors. Allergy Published by John Wiley & Sons Ltd.

Performance of the new automated Abbott RealTime MTB assay for rapid detection of Mycobacterium tuberculosis complex in respiratory specimens.

PubMed

Chen, J H K; She, K K K; Kwong, T-C; Wong, O-Y; Siu, G K H; Leung, C-C; Chang, K-C; Tam, C-M; Ho, P-L; Cheng, V C C; Yuen, K-Y; Yam, W-C

2015-09-01

The automated high-throughput Abbott RealTime MTB real-time PCR assay has been recently launched for Mycobacterium tuberculosis complex (MTBC) clinical diagnosis. This study would like to evaluate its performance. We first compared its diagnostic performance with the Roche Cobas TaqMan MTB assay on 214 clinical respiratory specimens. Prospective analysis of a total 520 specimens was then performed to further evaluate the Abbott assay. The Abbott assay showed a lower limit of detection at 22.5 AFB/ml, which was more sensitive than the Cobas assay (167.5 AFB/ml). The two assays demonstrated a significant difference in diagnostic performance (McNemar's test; P = 0.0034), in which the Abbott assay presented significantly higher area under curve (AUC) than the Cobas assay (1.000 vs 0.880; P = 0.0002). The Abbott assay demonstrated extremely low PCR inhibition on clinical respiratory specimens. The automated Abbott assay required only very short manual handling time (0.5 h), which could help to improve the laboratory management. In the prospective analysis, the overall estimates for sensitivity and specificity of the Abbott assay were both 100 % among smear-positive specimens, whereas the smear-negative specimens were 96.7 and 96.1 %, respectively. No cross-reactivity with non-tuberculosis mycobacterial species was observed. The superiority in sensitivity of the Abbott assay for detecting MTBC in smear-negative specimens could further minimize the risk in MTBC false-negative detection. The new Abbott RealTime MTB assay has good diagnostic performance which can be a useful diagnostic tool for rapid MTBC detection in clinical laboratories.

Comparative Evaluation of the Diagnostic Performance of the Prototype Cepheid GeneXpert Ebola Assay

PubMed Central

Jansen van Vuren, Petrus; Grobbelaar, Antoinette; Storm, Nadia; Conteh, Ousman; Konneh, Kelfala; Kamara, Abdul; Sanne, Ian

2015-01-01

The Ebola virus disease (EVD) outbreak in West Africa has highlighted an urgent need for point-of-care (POC) assays for the diagnosis of this devastating disease in resource-limited African countries. The diagnostic performance characteristics of a prototype Cepheid GeneXpert Ebola POC used to detect Ebola virus (EBOV) in stored serum and plasma samples collected from suspected EVD cases in Sierra Leone in 2014 and 2015 was evaluated. The GeneXpert Ebola POC is a self-contained single-cartridge automated system that targets the glycoprotein (GP) and nucleoprotein (NP) genes of EBOV and yields results within 90 min. Results from 281 patient samples were compared to the results of a TaqMan real-time reverse transcription-PCR (RT-PCR) targeting the polymerase gene and performed on two real-time PCR machines. Agreement between the three platforms was 100% at cycle threshold (CT) values of ≤34.99, but discordant results were noted between CT values of 35 and 45.The diagnostic sensitivity of the three platforms was 100% in 91 patient samples that were confirmed to be infectious by virus isolation. All three molecular platforms detected viral EBOV RNA in additional samples that did not contain viable EBOV. The analytical sensitivity of the GeneXpert Ebola POC for the detection of NP was higher, and comparable to that of polymerase gene detection, than that for the detection of GP when using a titrated laboratory stock of EBOV. There was no detectable cross-reactivity with other hemorrhagic fever viruses or arboviruses. The GeneXpert Ebola POC offers an easy to operate and sensitive diagnostic tool that can be used for the rapid screening of suspected EVD cases in treatment or in holding centers during EVD outbreaks. PMID:26637383

Comparison of Para-Selles Bailenger/Kop-Color Fumouze, Para-Selles-Iodésine/Kop-Color II Fumouze diagnostic kits with conventional microscopic methods in identifying intestinal parasitic diseases in Senegal.

PubMed

Sow, Doudou; Dieng, Yémou; Haouchine, Djamal; Niang, Khadim; Niang, Thiane; Sylla, Khadime; Tine, Roger Clément; Ndiaye, Magatte; Ndiaye, Jean Louis; Faye, Babacar; Faye, Omar; Gaye, Oumar; Dieng, Thérèse; Izri, Arezki

2017-09-01

In the context of controlling intestinal parasites, accurate diagnosis is essential. Our objective was to evaluate the performance of new diagnostic kits compared to conventional microscopic methods in identifying intestinal parasites. Faeces collected in rural area in Senegal were subjected to several detection techniques. Thus, the sensitivity, specificity, positive and negative predictive values of new diagnostic techniques were compared to conventional merthiolate-iodine-formalin, conventional Bailenger and modified Ritchie. Furthermore, the kappa coefficient was calculated to evaluate the correlation between the new kit and those of modified Ritchie. Out of the 117 patients examined, 102 presented with a parasite, or prevalence of 87.1%. The Fumouze techniques proved to be as effective as the conventional methods in detecting flagellates and helminths with sensitivities ranging from 97 to 100%. However, conventional techniques were slightly more sensitive in identifying Endolimax nana and Blastocystis hominis . The correlation was nearly perfect (k = 0.83 and 1), respectively between Bailenger Fumouze, Iodesine Fumouze and modified Ritchie in identifying helminths while it was just acceptable (k = 0.27 and 0.28) in identifying B. hominis . The modified Ritchie technique routinely used in our laboratory remains a good diagnostic tool. However, the use of kit techniques was interesting when reading the pellet after concentration and the Colour KOP staining was a considerable contribution to the diagnosis of the vegetative forms. Therefore, it would be interesting to determine the cost of a stool test using Fumouze kit techniques to provide the most cost effective way.

The diagnostic accuracy of the MyDiagnostick to detect atrial fibrillation in primary care

PubMed Central

2014-01-01

Background Atrial fibrillation is very common in people aged 65 or older. This condition increases the risk of death, congestive heart failure and thromboembolic conditions. Many patients with atrial fibrillation are asymptomatic and a cerebrovascular accident (CVA) is often the first clinical presentation. Guidelines concerning the prevention of CVA recommend monitoring the heart rate in patients aged 65 or older. Recently, the MyDiagnostick (Applied Biomedical Systems BV, Maastricht, The Netherlands) was introduced as a new screening tool which might serve as an alternative for the less accurate pulse palpation. This study was designed to explore the diagnostic accuracy of the MyDiagnostick for the detection of atrial fibrillation. Methods A phase II diagnostic accuracy study in a convenience sample of 191 subjects recruited in primary care. The majority of participants were patients with a known history of atrial fibrillation (n = 161). Readings of the MyDiagnostick were compared with electrocardiographic recordings. Sensitivity and specificity and their 95% confidence interval were calculated using 2x2 tables. Results A prevalence of 54% for an atrial fibrillation rhythm was found in the study population at the moment of the study. A combination of three measurements with the MyDiagnostick for each patient showed a sensitivity of 94% (95% CI 87 – 98) and a specificity of 93% (95% CI 85 – 97). Conclusion The MyDiagnostick is an easy-to-use device that showed a good diagnostic accuracy with a high sensitivity and specificity for atrial fibrillation in a convenience sample in primary care. Future research is needed to determine the place of the MyDiagnostick in possible screening or case-finding strategies for atrial fibrillation. PMID:24913608

C-reactive protein as a screening test for HIV-associated pulmonary tuberculosis prior to antiretroviral therapy in South Africa.

PubMed

Shapiro, Adrienne E; Hong, Ting; Govere, Sabina; Thulare, Hilary; Moosa, Mahomed-Yunus; Dorasamy, Afton; Wallis, Carole L; Celum, Connie L; Grosset, Jacques; Drain, Paul K

2018-05-28

There is an urgent need for more accurate screening tests for tuberculosis(TB). We assessed the diagnostic accuracy of C-reactive protein (CRP) as a screening test for active TB in HIV-infected ambulatory adults. CRP levels were measured in blood collected at the time of HIV testing.Diagnostic accuracy of CRP for pulmonary TB was calculated (reference standard: TB culture), compared to the WHO 4-symptom screen, consisting of cough, fever, night sweats, and weight loss. Diagnostic accuracy was also calculated for CRP in a larger cohort of HIV-infected adults with a positive symptom screen (reference standard: clinical or microbiological TB). Among 425 HIV-infected outpatients systematically tested for pulmonary TB, TB culture was positive in 42 (10%), 279 (66%) had at least one TB-related symptom and 197 (46%) had a CRP >5 mg/L. The sensitivity of CRP and the TB symptom screen to detect TB was the same (90.5%; 95%CI 77.4-97.3) but specificity of CRP was higher than for the TB symptom screen (58.5% vs. 37.1%, p<0.001). Of persons with no symptoms and normal CRP, 99 (98%) had no TB. In another cohort of 749 patients presenting with at least one TB-related symptom and clinically evaluated, CRP had a sensitivity of 98.7% and specificity of 48.3%. In HIV-infected outpatients, CRP was as sensitive but substantially more specific than TB symptom screening. Use of CRP as a screening tool to exclude active TB could identify the same number of HIV-associated TB cases, but reduce the use of diagnostic sputum testing in TB-endemic regions.

The development of a quality appraisal tool for studies of diagnostic reliability (QAREL).

PubMed

Lucas, Nicholas P; Macaskill, Petra; Irwig, Les; Bogduk, Nikolai

2010-08-01

In systematic reviews of the reliability of diagnostic tests, no quality assessment tool has been used consistently. The aim of this study was to develop a specific quality appraisal tool for studies of diagnostic reliability. Key principles for the quality of studies of diagnostic reliability were identified with reference to epidemiologic principles, existing quality appraisal checklists, and the Standards for Reporting of Diagnostic Accuracy (STARD) and Quality Assessment of Diagnostic Accuracy Studies (QUADAS) resources. Specific items that encompassed each of the principles were developed. Experts in diagnostic research provided feedback on the items that were to form the appraisal tool. This process was iterative and continued until consensus among experts was reached. The Quality Appraisal of Reliability Studies (QAREL) checklist includes 11 items that explore seven principles. Items cover the spectrum of subjects, spectrum of examiners, examiner blinding, order effects of examination, suitability of the time interval among repeated measurements, appropriate test application and interpretation, and appropriate statistical analysis. QAREL has been developed as a specific quality appraisal tool for studies of diagnostic reliability. The reliability of this tool in different contexts needs to be evaluated. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Nutritional assessment of community-dwelling older adults in rural Nepal

PubMed Central

Ghimire, Saruna; Baral, Binaya Kumar; Callahan, Karen

2017-01-01

Background Demographic transition in Nepal, like in many developing countries, has resulted in a burgeoning elderly population whose health status is not currently monitored. One pillar of health is adequate nutrition. Yet, little is known about the nutritional health status of the elderly in Nepal. The financial, material, and personnel limitations in Nepal’s health delivery services necessitate health screening instruments that require minimal clinical staff and resources. To our knowledge, no such nutritional assessment tool has been validated in Nepal. Therefore, our aims are two-fold: To assess the nutritional status of the elderly population in one typical Nepali village, Okharpauwa, in Nuwakot District, Nepal; and concurrently, to validate the Mini Nutritional Assessment (MNA) tool. Methods A cross-sectional field study was conducted with a sample of 242 elderly people in Okharpauwa, Nepal to obtain prevalence of malnutrition. Differences in demographic and lifestyle factors between these who were malnourished, those at risk of malnourishment, and those who had adequate nutritional status were analyzed. The MNA tool was evaluated using receiver operating characteristic (ROC) curve analysis; sensitivity, specificity, and diagnostic accuracy were calculated. Results 111 males and 131 females, with a mean age of 69.8±7.4 years, participated in this study. The mean BMI of the participants was 21.4±3.9 kg/m2; the mean MNA score was 19.3±4.2. BMI was significantly correlated with the total MNA score (r = 0.58; p<0.001). The diagnostic accuracy, sensitivity and specificity of MNA were 81%, 86% and 67% respectively. Of the 242 elderly sampled, 24% were malnourished and 65% were at risk of malnutrition. Malnutrition was more prevalent among females (29%) than males (18%), and most prevalent among the marginalized Dalit ethnic group (40%). Elderly persons who were married and literate had better nutritional health than their counterparts. Conclusions The MNA appears to be a valid and sensitive tool for rapid nutritional screening of the elderly in Nepal. The prevalence of malnutrition was high among Nepalese elderly in the Okharpauwa VDC, which requires urgent health monitoring and management attention. PMID:28196115

Nutritional assessment of community-dwelling older adults in rural Nepal.

PubMed

Ghimire, Saruna; Baral, Binaya Kumar; Callahan, Karen

2017-01-01

Demographic transition in Nepal, like in many developing countries, has resulted in a burgeoning elderly population whose health status is not currently monitored. One pillar of health is adequate nutrition. Yet, little is known about the nutritional health status of the elderly in Nepal. The financial, material, and personnel limitations in Nepal's health delivery services necessitate health screening instruments that require minimal clinical staff and resources. To our knowledge, no such nutritional assessment tool has been validated in Nepal. Therefore, our aims are two-fold: To assess the nutritional status of the elderly population in one typical Nepali village, Okharpauwa, in Nuwakot District, Nepal; and concurrently, to validate the Mini Nutritional Assessment (MNA) tool. A cross-sectional field study was conducted with a sample of 242 elderly people in Okharpauwa, Nepal to obtain prevalence of malnutrition. Differences in demographic and lifestyle factors between these who were malnourished, those at risk of malnourishment, and those who had adequate nutritional status were analyzed. The MNA tool was evaluated using receiver operating characteristic (ROC) curve analysis; sensitivity, specificity, and diagnostic accuracy were calculated. 111 males and 131 females, with a mean age of 69.8±7.4 years, participated in this study. The mean BMI of the participants was 21.4±3.9 kg/m2; the mean MNA score was 19.3±4.2. BMI was significantly correlated with the total MNA score (r = 0.58; p<0.001). The diagnostic accuracy, sensitivity and specificity of MNA were 81%, 86% and 67% respectively. Of the 242 elderly sampled, 24% were malnourished and 65% were at risk of malnutrition. Malnutrition was more prevalent among females (29%) than males (18%), and most prevalent among the marginalized Dalit ethnic group (40%). Elderly persons who were married and literate had better nutritional health than their counterparts. The MNA appears to be a valid and sensitive tool for rapid nutritional screening of the elderly in Nepal. The prevalence of malnutrition was high among Nepalese elderly in the Okharpauwa VDC, which requires urgent health monitoring and management attention.

An accuracy evaluation of clinical, arthrometric, and stress-sonographic acute ankle instability examinations.

PubMed

Wiebking, Ulrich; Pacha, Tarek Omar; Jagodzinski, Michael

2015-03-01

Ankle sprain injuries, often due to lateral ligamentous injury, are the most common sports traumatology conditions. Correct diagnoses require an understanding of the assessment tools with a high degree of diagnostic accuracy. Obviously, there are still no clear consensuses or standard methods to differentiate between a ligament tear and an ankle sprain. In addition to clinical assessments, stress sonography, arthrometer and other methods are often performed simultaneously. These methods are often costly, however, and their accuracy is controversial. The aim of this study was to investigate three different measurement tools that can be used after a lateral ligament lesion of the ankle with injury of the anterior talofibular ligament to determine their diagnostic accuracy. Thirty patients were recruited for this study. The mean patient age was 35±14 years. There were 15 patients with a ligamentous rupture and 15 patients with an ankle sprain. We quantified two devices and one clinical assessment by which we calculated the sensitivity and specifity: Stress sonography according to Hoffmann, an arthrometer to investigate the 100N talar drawer and maximum manual testing and the clinical assessment of the anterior drawer test. A high resolution sonography was used as the gold standard. The ultrasound-assisted gadgetry according to Hoffmann, with a 3mm cut-off value, displayed a sensitivity of 0.27 and a specificity of 0.87. Using a 3.95mm cut-off value, the arthrometer displayed a sensitivity of 0.8 and a specificity of 0.4. The clinical investigation sensitivities and specificities were 0.93 and 0.67, respectively. Different assessment methods for ankle rupture diagnoses are suggested in the literature; however, these methods lack reliable data to set investigation standards. Clinical examination under adequate analgesia seems to remains the most reliable tool to investigate ligamentous ankle lesions. Further clinical studies with higher case numbers are necessary, however, to evaluate these findings and to measure the reliability. Copyright © 2014 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Rapid Accurate Identification of Tuberculous Meningitis Among South African Children Using a Novel Clinical Decision Tool.

PubMed

Goenka, Anu; Jeena, Prakash M; Mlisana, Koleka; Solomon, Tom; Spicer, Kevin; Stephenson, Rebecca; Verma, Arpana; Dhada, Barnesh; Griffiths, Michael J

2018-03-01

Early diagnosis of tuberculous meningitis (TBM) is crucial to achieve optimum outcomes. There is no effective rapid diagnostic test for use in children. We aimed to develop a clinical decision tool to facilitate the early diagnosis of childhood TBM. Retrospective case-control study was performed across 7 hospitals in KwaZulu-Natal, South Africa (2010-2014). We identified the variables most predictive of microbiologically confirmed TBM in children (3 months to 15 years) by univariate analysis. These variables were modelled into a clinical decision tool and performance tested on an independent sample group. Of 865 children with suspected TBM, 3% (25) were identified with microbiologically confirmed TBM. Clinical information was retrieved for 22 microbiologically confirmed cases of TBM and compared with 66 controls matched for age, ethnicity, sex and geographical origin. The 9 most predictive variables among the confirmed cases were used to develop a clinical decision tool (CHILD TB LP): altered Consciousness; caregiver HIV infected; Illness length >7 days; Lethargy; focal neurologic Deficit; failure to Thrive; Blood/serum sodium <132 mmol/L; CSF >10 Lymphocytes ×10/L; CSF Protein >0.65 g/L. This tool successfully classified an independent sample of 7 cases and 21 controls with a sensitivity of 100% and specificity of 90%. The CHILD TB LP decision tool accurately classified microbiologically confirmed TBM. We propose that CHILD TB LP is prospectively evaluated as a novel rapid diagnostic tool for use in the initial evaluation of children with suspected neurologic infection presenting to hospitals in similar settings.

Validation of an automatically generated screening score for frailty: the care assessment need (CAN) score.

PubMed

Ruiz, Jorge G; Priyadarshni, Shivani; Rahaman, Zubair; Cabrera, Kimberly; Dang, Stuti; Valencia, Willy M; Mintzer, Michael J

2018-05-04

Frailty is a state of vulnerability to stressors that is prevalent in older adults and is associated with higher morbidity, mortality and healthcare utilization. Multiple instruments are used to measure frailty; most are time-consuming. The Care Assessment Need (CAN) score is automatically generated from electronic health record data using a statistical model. The methodology for calculation of the CAN score is consistent with the deficit accumulation model of frailty. At a 95 percentile, the CAN score is a predictor of hospitalization and mortality in Veteran populations. The purpose of this study was to validate the CAN score as a screening tool for frailty in primary care. This is a cross-sectional, validation study compared the CAN score with a 40-item Frailty Index reference standard based on a comprehensive geriatric assessment. We included community-dwelling male patients over age 65 from an outpatient geriatric medicine clinic. We calculated the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of the CAN score. 184 patients over age 65 were included in the study: 97.3% male, 64.2% White, 80.9% non-Hispanic. The CGA-based Frailty Index defined 14.1% as robust, 53.3% as prefrail and 32.6% as frail. For the frail, statistical analysis demonstrated that a CAN score of 55 provides sensitivity, specificity, PPV and NPV of 91.67, 40.32, 42.64 and 90.91% respectively whereas at a score of 95 the sensitivity, specificity, PPV and NPV were 43.33, 88.81, 63.41, 77.78% respectively. Area under the receiver operating characteristics curve was 0.736 (95% CI = .661-.811). CAN score is a potential screening tool for frailty among older adults; it is generated automatically and provides acceptable diagnostic accuracy. Hence, the CAN score may be a useful tool to primary care providers for detection of frailty in their patient panels.

Super-Resolution Microscopy of Cerebrospinal Fluid Biomarkers as a Tool for Alzheimer's Disease Diagnostics.

PubMed

Zhang, William I; Antonios, Gregory; Rabano, Alberto; Bayer, Thomas A; Schneider, Anja; Rizzoli, Silvio O

2015-01-01

Alzheimer's disease (AD) is neuropathologically characterized by aggregates of amyloid-β peptides (Aβ) and tau proteins. The consensus in the AD field is that Aβ and tau should serve as diagnostic biomarkers for AD. However, their aggregates have been difficult to investigate by conventional fluorescence microscopy, since their size is below the diffraction limit (∼200 nm). To solve this, we turned to a super-resolution imaging technique, stimulated emission depletion (STED) microscopy, which has a high enough precision to allow the discrimination of low- and high-molecular weight aggregates prepared in vitro. We used STED to analyze the structural organization of Aβ and tau in cerebrospinal fluid (CSF) from 36 AD patients, 11 patients with mild cognitive impairment (MCI), and 21 controls. We measured the numbers of aggregates in the CSF samples, and the aggregate sizes and intensities. These parameters enabled us to distinguish AD patients from controls with a specificity of ∼87% and a sensitivity of ∼79% . In addition, the aggregate parameters determined with STED microscopy correlated with the severity of cognitive impairment in AD patients. Finally, these parameters may be useful as predictive tools for MCI cases. The STED parameters of two MCI patients who developed AD during the course of the study, as well as of MCI patients whose Aβ ELISA values fall within the accepted range for AD, placed them close to the AD averages. We suggest that super-resolution imaging is a promising tool for AD diagnostics.

Delving into cornerstones of hypersensitivity to antineoplastic and biological agents: value of diagnostic tools prior to desensitization.

PubMed

Alvarez-Cuesta, E; Madrigal-Burgaleta, R; Angel-Pereira, D; Ureña-Tavera, A; Zamora-Verduga, M; Lopez-Gonzalez, P; Berges-Gimeno, M P

2015-07-01

Evidence regarding drug provocation test (DPT) with antineoplastic and biological agents is scarce. Our aim was to assess the usefulness of including DPT as a paramount gold standard diagnostic tool (prior to desensitization). Prospective, observational, longitudinal study with patients who, during a 3-year period, were referred to the Desensitization Program at Ramon y Cajal University Hospital. Patients underwent a structured diagnostic protocol by means of anamnesis, skin tests (ST), risk assessment, and DPT. Oxaliplatin-specific IgE was determined in oxaliplatin-reactive patients (who underwent DPT regardless of oxaliplatin-specific IgE results). Univariate analysis and multivariate analysis were used to identify predictors of the final diagnosis among several variables. A total of 186 patients were assessed. A total of 104 (56%) patients underwent DPT. Sixty-four percent of all DPTs were negative (i.e., hypersensitivity was excluded). Sensitivity for oxaliplatin-specific IgE (0.35 UI/l cutoff point) was 34%, specificity 90.3%, negative predictive value 45.9%, positive predictive value 85%, negative likelihood ratio 0.7, and positive likelihood ratio 3.5. These are the first reported data based on more than 100 DPTs with antineoplastic and biological agents (paclitaxel, oxaliplatin, rituximab, infliximab, irinotecan, and other drugs). Implementation of DPT in diagnostic protocols helps exclude hypersensitivity (in 36% of all referred patients), and avoids unnecessary desensitizations in nonhypersensitive patients (30-56% of patients, depending on culprit-drug). Drug provocation test is vital to validate diagnostic tools; consequently, quality data are shown on oxaliplatin-specific IgE and oxaliplatin-ST in the largest series of oxaliplatin-reactive patients reported to date (74 oxaliplatin-reactive patients). Identifying phenotypes and predictors of a diagnosis of hypersensitivity may be helpful for tailored plans. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Role of nasal challenge and local eosinophilia in indirect exposure to cat in allergic rhinitis patients.

PubMed

Al Ahmad, M; Arifhodzic, N; Nurkic, J; Jusufovic, E; Hanoun, A L; Rodriguez, T

2018-01-17

Introduction. Sensitization to cat allergens is common worldwide. Currently, there is a trend towards costly and often unavailable diagnostic analysis. Objectives. The aim is to assess the reliability of skin prick test (SPT) and serum specific IgE (ssIgE) to cat sensitization, by performing nasal challenge test (NCT) in a community with low cat ownership but common presence of stray cats. Patients and methods. Forty-one pa-tients with perennial allergic rhinitis (AR) who were mono or polysensitized (including cat) were included. We had 31 cat non-owners and 10 present cat owners. SPT (> 5 mm / diameter), ssIgE (≥ 0.70 IU/ml), nasal smear for eosinophil (Eo) and NCT were compared between groups. Outcomes included nasal challenge score, nasal Eo positivity, peak inspiratory and expiratory flow (PIF and PEF) 2 and 8 hours after the NCT, and were compared to baseline. Results. Baseline SPT wheal size and ssIgE level were similar in both groups. NCT positivity was more frequent in cat owners. The strongest nasal reaction was on the top concentration in both groups. Nasal Eo positivity in cat owners was higher before and 2 hours after NCT, but similar to non-owners at last measurement. NCT positive cat non-owners had bigger SPT wheal size than NCT negative non-owners, but smaller than NCT positive cat owners. In contrast to PEF, a significant fall in PIF was noticed in both groups. Mono and polysensitised patients showed similar NCT positivity. Conclusion. Stray cats may pose a relevant risk of developing perennial AR. Regardless of cat ownership status, SPT and ssIgE should be the first diagnostic tool. Nasal Eo and NCT seem to be good diagnostic tools in cat non-owners if diagnosis is elusive.

Nanostructured plasmonic interferometers for ultrasensitive label-free biosensing

NASA Astrophysics Data System (ADS)

Gao, Yongkang

Optical biosensors that utilize surface plasmon resonance (SPR) technique to analyze the biomolecular interactions have been extensively explored in the last two decades and have become the gold standard for label-free biosensing. These powerful sensing tools allow fast, highly-sensitive monitoring of the interaction between biomolecules in real time, without the need for laborious fluorescent labeling, and have found widely ranging applications from biomedical diagnostics and drug discovery, to environmental sensing and food safety monitoring. However, the prism-coupling SPR geometry is complex and bulky, and has severely limited the integration of this technique into low-cost portable biomedical devices for point-of-care diagnostics and personal healthcare applications. Also, the complex prism-coupling scheme prevents the use of high numerical aperture (NA) optics to increase the spatial resolution for multi-channel, high-throughput detection in SPR imaging mode. This dissertation is focused on the design and fabrication of a promising new class of nanopatterned interferometric SPR sensors that integrate the strengths of miniaturized nanoplasmonic architectures with sensitive optical interferometry techniques to achieve bold advances in SPR biosensing. The nanosensor chips developed provide superior sensing performance comparable to conventional SPR systems, but employing a far simpler collinear optical transmission geometry, which largely facilitates system integration, miniaturization, and low-cost production. Moreover, the fabricated nanostructure-based SPR sensors feature a very small sensor footprint, allowing massive multiplexing on a chip for high-throughput detection. The successful transformation of SPR technique from bulky prism-coupling setup into this low-cost compact plasmonic platform would have a far-reaching impact on point-of-care diagnostic tools and also lead to advances in high-throughput sensing applications in proteomics, immunology, drug discovery, and fundamental cell biology research.

Improved Diagnostic Accuracy of SPECT Through Statistical Analysis and the Detection of Hot Spots at the Primary Sensorimotor Area for the Diagnosis of Alzheimer Disease in a Community-Based Study: "The Osaki-Tajiri Project".

PubMed

Kaneta, Tomohiro; Nakatsuka, Masahiro; Nakamura, Kei; Seki, Takashi; Yamaguchi, Satoshi; Tsuboi, Masahiro; Meguro, Kenichi

2016-01-01

SPECT is an important diagnostic tool for dementia. Recently, statistical analysis of SPECT has been commonly used for dementia research. In this study, we evaluated the accuracy of visual SPECT evaluation and/or statistical analysis for the diagnosis (Dx) of Alzheimer disease (AD) and other forms of dementia in our community-based study "The Osaki-Tajiri Project." Eighty-nine consecutive outpatients with dementia were enrolled and underwent brain perfusion SPECT with 99mTc-ECD. Diagnostic accuracy of SPECT was tested using 3 methods: visual inspection (SPECT Dx), automated diagnostic tool using statistical analysis with easy Z-score imaging system (eZIS Dx), and visual inspection plus eZIS (integrated Dx). Integrated Dx showed the highest sensitivity, specificity, and accuracy, whereas eZIS was the second most accurate method. We also observed that a higher than expected rate of SPECT images indicated false-negative cases of AD. Among these, 50% showed hypofrontality and were diagnosed as frontotemporal lobar degeneration. These cases typically showed regional "hot spots" in the primary sensorimotor cortex (ie, a sensorimotor hot spot sign), which we determined were associated with AD rather than frontotemporal lobar degeneration. We concluded that the diagnostic abilities were improved by the integrated use of visual assessment and statistical analysis. In addition, the detection of a sensorimotor hot spot sign was useful to detect AD when hypofrontality is present and improved the ability to properly diagnose AD.

Macular Diagnostic Ability in OCT for Assessing Glaucoma in High Myopia.

PubMed

Hung, Kuo-Chi; Wu, Pei-Chang; Poon, Yi-Chieh; Chang, Hsueh-Wen; Lai, Ing-Chou; Tsai, Jen-Chia; Lin, Pei-Wen; Teng, Mei-Ching

2016-02-01

To compare the diagnostic abilities of spectral-domain optical coherence tomography (SD-OCT; Spectralis OCT) and time-domain OCT (TD-OCT; Stratus OCT). Changes in macular parameters in highly myopic eyes of glaucoma patients and highly myopic eyes of glaucoma suspects were evaluated and compared. We collected data from 72 highly myopic eyes (spherical equivalent, ≤-6.0D). Forty-one eyes had perimetric glaucoma and 31 eyes were suspected to have glaucoma (control group). All eyes underwent SD-OCT and TD-OCT imaging. Area under the receiver operating characteristic (AUROC) curve and sensitivity were examined on macular volume and thickness parameters at a fixed specificity and compared between groups. The highest TD-OCT AUROC curves were found using outer inferior sector macular thickness (AUROC curve, 0.911) and volume (AUROC curve, 0.909). The highest SD-OCT AUROC curves were found using outer inferior region thickness (AUROC curve, 0.836) and volume (AUROC curve, 0.834). The difference between the two imaging modalities was not statistically significant (thickness, p = 0.141; volume, p = 0.138). The sensitivity of TD-OCT macular outer inferior average thickness was highest and was 88.2%, with a specificity of 80.4%. The sensitivity of TD-OCT average volume measurements in this same region was 76.5%, with a specificity of 91.3%. The SD-OCT average thickness measurements also had the highest sensitivity in this region, which was 78.6%, with a specificity of 82.1%. The SD-OCT volume measurements had a sensitivity of 67.9%, with a specificity of 92.3%. Both SD-OCT and TD-OCT measurements of outer inferior macular thickness and volume can differentiate between eyes of glaucoma patients and glaucoma suspects with high myopia. These independent predictors all had good sensitivity. Based on our results, SD-OCT and TD-OCT have similar diagnostic abilities. These parameters may provide useful additional data in highly myopic eyes to complement standard glaucoma diagnosis tools.

Interpreting ambiguous 'trace' results in Schistosoma mansoni CCA Tests: Estimating sensitivity and specificity of ambiguous results with no gold standard.

PubMed

Clements, Michelle N; Donnelly, Christl A; Fenwick, Alan; Kabatereine, Narcis B; Knowles, Sarah C L; Meité, Aboulaye; N'Goran, Eliézer K; Nalule, Yolisa; Nogaro, Sarah; Phillips, Anna E; Tukahebwa, Edridah Muheki; Fleming, Fiona M

2017-12-01

The development of new diagnostics is an important tool in the fight against disease. Latent Class Analysis (LCA) is used to estimate the sensitivity and specificity of tests in the absence of a gold standard. The main field diagnostic for Schistosoma mansoni infection, Kato-Katz (KK), is not very sensitive at low infection intensities. A point-of-care circulating cathodic antigen (CCA) test has been shown to be more sensitive than KK. However, CCA can return an ambiguous 'trace' result between 'positive' and 'negative', and much debate has focused on interpretation of traces results. We show how LCA can be extended to include ambiguous trace results and analyse S. mansoni studies from both Côte d'Ivoire (CdI) and Uganda. We compare the diagnostic performance of KK and CCA and the observed results by each test to the estimated infection prevalence in the population. Prevalence by KK was higher in CdI (13.4%) than in Uganda (6.1%), but prevalence by CCA was similar between countries, both when trace was assumed to be negative (CCAtn: 11.7% in CdI and 9.7% in Uganda) and positive (CCAtp: 20.1% in CdI and 22.5% in Uganda). The estimated sensitivity of CCA was more consistent between countries than the estimated sensitivity of KK, and estimated infection prevalence did not significantly differ between CdI (20.5%) and Uganda (19.1%). The prevalence by CCA with trace as positive did not differ significantly from estimates of infection prevalence in either country, whereas both KK and CCA with trace as negative significantly underestimated infection prevalence in both countries. Incorporation of ambiguous results into an LCA enables the effect of different treatment thresholds to be directly assessed and is applicable in many fields. Our results showed that CCA with trace as positive most accurately estimated infection prevalence.

Interpreting ambiguous ‘trace’ results in Schistosoma mansoni CCA Tests: Estimating sensitivity and specificity of ambiguous results with no gold standard

PubMed Central

Donnelly, Christl A.; Fenwick, Alan; Kabatereine, Narcis B.; Knowles, Sarah C. L.; Meité, Aboulaye; N'Goran, Eliézer K.; Nalule, Yolisa; Nogaro, Sarah; Phillips, Anna E.; Tukahebwa, Edridah Muheki; Fleming, Fiona M.

2017-01-01

Background The development of new diagnostics is an important tool in the fight against disease. Latent Class Analysis (LCA) is used to estimate the sensitivity and specificity of tests in the absence of a gold standard. The main field diagnostic for Schistosoma mansoni infection, Kato-Katz (KK), is not very sensitive at low infection intensities. A point-of-care circulating cathodic antigen (CCA) test has been shown to be more sensitive than KK. However, CCA can return an ambiguous ‘trace’ result between ‘positive’ and ‘negative’, and much debate has focused on interpretation of traces results. Methodology/Principle findings We show how LCA can be extended to include ambiguous trace results and analyse S. mansoni studies from both Côte d’Ivoire (CdI) and Uganda. We compare the diagnostic performance of KK and CCA and the observed results by each test to the estimated infection prevalence in the population. Prevalence by KK was higher in CdI (13.4%) than in Uganda (6.1%), but prevalence by CCA was similar between countries, both when trace was assumed to be negative (CCAtn: 11.7% in CdI and 9.7% in Uganda) and positive (CCAtp: 20.1% in CdI and 22.5% in Uganda). The estimated sensitivity of CCA was more consistent between countries than the estimated sensitivity of KK, and estimated infection prevalence did not significantly differ between CdI (20.5%) and Uganda (19.1%). The prevalence by CCA with trace as positive did not differ significantly from estimates of infection prevalence in either country, whereas both KK and CCA with trace as negative significantly underestimated infection prevalence in both countries. Conclusions Incorporation of ambiguous results into an LCA enables the effect of different treatment thresholds to be directly assessed and is applicable in many fields. Our results showed that CCA with trace as positive most accurately estimated infection prevalence. PMID:29220354

Diagnostic testing for celiac disease among patients with abdominal symptoms: a systematic review.

PubMed

van der Windt, Daniëlle A W M; Jellema, Petra; Mulder, Chris J; Kneepkens, C M Frank; van der Horst, Henriëtte E

2010-05-05

The symptoms and consequences of celiac disease usually resolve with a lifelong gluten-free diet. However, clinical presentation is variable and most patients presenting with abdominal symptoms in primary care will not have celiac disease and unnecessary diagnostic testing should be avoided. To summarize evidence on the performance of diagnostic tests for identifying celiac disease in adults presenting with abdominal symptoms in primary care or similar settings. A literature search via MEDLINE (beginning in January 1966) and EMBASE (beginning in January 1947) through December 2009 and a manual search of references for additional relevant studies. Diagnostic studies were selected if they had a cohort or nested case-control design, enrolled adults presenting with nonacute abdominal symptoms, the prevalence of celiac disease was 15% or less, and the tests used included gastrointestinal symptoms or serum antibody tests. Quality assessment using the Quality Assessment of Diagnostic Accuracy Studies tool and data extraction were performed by 2 reviewers independently. Sensitivities and specificities were calculated for each study and pooled estimates were computed using bivariate analysis if there was clinical and statistical homogeneity. Sixteen studies were included in the review (N = 6085 patients). The performance of abdominal symptoms varied widely. The sensitivity of diarrhea, for example, ranged from 0.27 to 0.86 and specificity from 0.21 to 0.86. Pooled estimates for IgA antiendomysial antibodies (8 studies) were 0.90 (95% confidence interval [CI], 0.80-0.95) for sensitivity and 0.99 (95% CI, 0.98-1.00) for specificity (positive likelihood ratio [LR] of 171 and negative LR of 0.11). Pooled estimates for IgA antitissue transglutaminase antibodies (7 studies) were 0.89 (95% CI, 0.82-0.94) and 0.98 (95% CI, 0.95-0.99), respectively (positive LR of 37.7 and negative LR of 0.11). The IgA and IgG antigliadin antibodies showed variable results, especially for sensitivity (range, 0.46-0.87 and range, 0.25-0.93, respectively). One recent study using diamidated gliadin peptides showed good specificity (> or = 0.94), but evidence is limited in this target population. Among adult patients presenting with abdominal symptoms in primary care or other unselected populations, IgA antitissue transglutaminase antibodies and IgA antiendomysial antibodies have high sensitivity and specificity for diagnosing celiac disease.

Target prioritization and strategy selection for active case-finding of pulmonary tuberculosis: a tool to support country-level project planning.

PubMed

Nishikiori, Nobuyuki; Van Weezenbeek, Catharina

2013-02-02

Despite the progress made in the past decade, tuberculosis (TB) control still faces significant challenges. In many countries with declining TB incidence, the disease tends to concentrate in vulnerable populations that often have limited access to health care. In light of the limitations of the current case-finding approach and the global urgency to improve case detection, active case-finding (ACF) has been suggested as an important complementary strategy to accelerate tuberculosis control especially among high-risk populations. The present exercise aims to develop a model that can be used for county-level project planning. A simple deterministic model was developed to calculate the number of estimated TB cases diagnosed and the associated costs of diagnosis. The model was designed to compare cost-effectiveness parameters, such as the cost per case detected, for different diagnostic algorithms when they are applied to different risk populations. The model was transformed into a web-based tool that can support national TB programmes and civil society partners in designing ACF activities. According to the model output, tuberculosis active case-finding can be a costly endeavor, depending on the target population and the diagnostic strategy. The analysis suggests the following: (1) Active case-finding activities are cost-effective only if the tuberculosis prevalence among the target population is high. (2) Extensive diagnostic methods (e.g. X-ray screening for the entire group, use of sputum culture or molecular diagnostics) can be applied only to very high-risk groups such as TB contacts, prisoners or people living with human immunodeficiency virus (HIV) infection. (3) Basic diagnostic approaches such as TB symptom screening are always applicable although the diagnostic yield is very limited. The cost-effectiveness parameter was sensitive to local diagnostic costs and the tuberculosis prevalence of target populations. The prioritization of appropriate target populations and careful selection of cost-effective diagnostic strategies are critical prerequisites for rational active case-finding activities. A decision to conduct such activities should be based on the setting-specific cost-effectiveness analysis and programmatic assessment. A web-based tool was developed and is available to support national tuberculosis programmes and partners in the formulation of cost-effective active case-finding activities at the national and subnational levels.

Peptide nanotube-modified electrodes for enzyme-biosensor applications.

PubMed

Yemini, Miri; Reches, Meital; Gazit, Ehud; Rishpon, Judith

2005-08-15

The fabrication and notably improved performance of composite electrodes based on modified self-assembled diphenylalanine peptide nanotubes is described. Peptide nanotubes were attached to gold electrodes, and we studied the resulting electrochemical behavior using cyclic voltammetry and chronoamperometry. The peptide nanotube-based electrodes demonstrated a direct and unmediated response to hydrogen peroxide and NADH at a potential of +0.4 V (vs SCE). This biosensor enables a sensitive determination of glucose by monitoring the hydrogen peroxide produced by an enzymatic reaction between the glucose oxidase attached to the peptide nanotubes and glucose. In addition, the marked electrocatalytic activity toward NADH enabled a sensitive detection of ethanol using ethanol dehydrogenase and NAD+. The peptide nanotube-based amperometric biosensor provides a potential new tool for sensitive biosensors and biomolecular diagnostics.

Diagnostic Accuracy of Ascites Fluid Gross Appearance in Detection of Spontaneous Bacterial Peritonitis.

PubMed

Aminiahidashti, Hamed; Hosseininejad, Seyed Mohammad; Montazer, Hosein; Bozorgi, Farzad; Goli Khatir, Iraj; Jahanian, Fateme; Raee, Behnaz

2014-01-01

Spontaneous bacterial peritonitis (SBP) as a monomicrobial infection of ascites fluid is one of the most important causes of morbidity and mortality in cirrhotic patients. This study was aimed to determine the diagnostic accuracy of ascites fluid color in detection of SBP in cirrhotic cases referred to the emergency department. Cirrhotic patients referred to the ED for the paracentesis of ascites fluid were enrolled. For all studied patients, the results of laboratory analysis and gross appearance of ascites fluid registered and reviewed by two emergency medicine specialists. The sensitivity, specificity, positive and negative predictive value, and positive and negative likelihood ration of the ascites fluid gross appearance in detection of SBP were measured with 95% confidence interval. The present project was performed in 80 cirrhotic patients with ascites (52.5 female). The mean of the subjects' age was 56.25±12.21 years (35-81). Laboratory findings revealed SBP in 23 (29%) cases. Fifty nine (73%) cases had transparent ascites fluid appearance of whom 17 (29%) ones suffered from SBP. From 21 (26%) cases with opaque ascites appearance, 15 (71%) had SBP. The sensitivity and specificity of the ascites fluid appearance in detection of SBP were 46.88% (Cl: 30.87-63.55) and 87.50% (95% Cl: 75.3-94.14), respectively. It seems that the gross appearance of ascites fluid had poor diagnostic accuracy in detection of SBP and considering its low sensitivity, it could not be used as a good screening tool for this propose.

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 Validity of an Automated Probabilistic Tractography in Amnestic Mild Cognitive Impairment

PubMed Central

Jung, Won Sang; Um, Yoo Hyun; Kang, Dong Woo; Lee, Chang Uk; Woo, Young Sup; Bahk, Won-Myong

2018-01-01

Objective Although several prior works showed the white matter (WM) integrity changes in amnestic mild cognitive impairment (aMCI) and Alzheimer’s disease, it is still unclear the diagnostic accuracy of the WM integrity measurements using diffusion tensor imaging (DTI) in discriminating aMCI from normal controls. The aim of this study is to explore diagnostic validity of whole brain automated probabilistic tractography in discriminating aMCI from normal controls. Methods One hundred-two subjects (50 aMCI and 52 normal controls) were included and underwent DTI scans. Whole brain WM tracts were reconstructed with automated probabilistic tractography. Fractional anisotropy (FA) and mean diffusivity (MD) values of the memory related WM tracts were measured and compared between the aMCI and the normal control groups. In addition, the diagnostic validities of these WM tracts were evaluated. Results Decreased FA and increased MD values of memory related WM tracts were observed in the aMCI group compared with the control group. Among FA and MD value of each tract, the FA value of left cingulum angular bundle showed the highest area under the curve (AUC) of 0.85 with a sensitivity of 88.2%, a specificity of 76.9% in differentiating MCI patients from control subjects. Furthermore, the combination FA values of WM integrity measures of memory related WM tracts showed AUC value of 0.98, a sensitivity of 96%, a specificity of 94.2%. Conclusion Our results with good diagnostic validity of WM integrity measurements suggest DTI might be promising neuroimaging tool for early detection of aMCI and AD patients. PMID:29739127

Evaluation of Accuracy of DIAGNOdent in Diagnosis of Primary and Secondary Caries in Comparison to Conventional Methods

PubMed Central

Nokhbatolfoghahaie, Hanieh; Alikhasi, Marzieh; Chiniforush, Nasim; Khoei, Farzaneh; Safavi, Nassimeh; Yaghoub Zadeh, Behnoush

2013-01-01

Introduction: Today the prevalence of teeth decays has considerably decreased. Related organizations and institutions mention several reasons for it such as improvement of decay diagnostic equipment and tools which are even capable of detecting caries in their initial stages. This resulted in reduction of costs for patients and remarkable increase in teeth life span. There are many methods for decay diagnostic, like: visual and radiographic methods, devices with fluorescence such as Quantitative light-induced fluorescence (QLF), Vista proof, Laser fluorescence (LF or DIAGNOdent), Fluorescence Camera (FC) and Digital radiography. Although DIAGNOdent is considered a valuable device for decay diagnostic ,there are concerns regarding its efficacy and accuracy. Considering the sensitivity of decaydiagnosis and the exorbitant annual expenses supported by government and people for caries treatment, finding the best method for early caries detection is of the most importance. Numerous studies were performed to compare different diagnostic methods with conflicting results. The objective of this study is a comparative review of the efficiency of DIAGNOdent in comparison to visual methods and radiographic methods in the diagnostic of teeth occlusal surfaces. Methods: Search of PubMed, Google Scholar electronic resources was performed in order to find clinical trials in English in the period between 1998 and 2013. Full texts of only 35 articles were available. Conclusion: Considering the sensitivity and specificity reported in the different studies, it seems that DIAGNOdent is an appropriate modality for caries detection as a complementary method beside other methods and its use alone to obtain treatment plan is not enough. PMID:25606325

Affirm VPIII microbial identification test can be used to detect gardnerella vaginalis, Candida albicans and trichomonas vaginalis microbial infections in Korean women.

PubMed

Byun, Seung Won; Park, Yeon Joon; Hur, Soo Young

2016-04-01

The aim of this study was to compare Affirm VPIII Microbial Identification Test results for Korean women to those obtained for Gardnerella vaginalis through Nugent score, Candida albicans based on vaginal culture and Trichomonas vaginalis based on wet smear diagnostic standards. Study participants included 195 women with symptomatic or asymptomatic vulvovaginitis under hospital obstetric or gynecologic care. A definite diagnosis was made based on Nugent score for Gardnerella, vaginal culture for Candida and wet prep for Trichomonas vaginalis. Affirm VPIII Microbial Identification Test results were then compared to diagnostic standard results. Of the 195 participants, 152 were symptomatic, while 43 were asymptomatic. Final diagnosis revealed 68 (37.87%) cases of Gardnerella, 29 (14.87%) cases of Candida, one (0.51%) case of Trichomonas, and 10 (5.10%) cases of mixed infections. The detection rates achieved by each detection method (Affirm assay vs diagnostic standard) for Gardnerella and Candida were not significantly different (33.33% vs 34.8% for Gardnerella, 13.33% vs 14.87% for Candida, respectively). The sensitivity and specificity of the Affirm test for Gardnerella compared to the diagnostic standard were 75.0% and 88.98%, respectively. For Candida, the sensitivity and specificity of the Affirm test compared to the diagnostic standard were 82.76% and 98.80%, respectively. The number of Trichomonas cases was too small (1 case) to be statistically analyzed. The Affirm test is a quick tool that can help physicians diagnose and treat patients with infectious vaginitis at the point of care. © 2016 Japan Society of Obstetrics and Gynecology.

The role of latex agglutination test for the etiological diagnosis of pleural effusion in children and adolescents.

PubMed

Camargos, Paulo; Fonseca, Ana Cristina; Amantéa, Sérgio; Oliveira, Elizabeth; Benfica, Maria das Graças; Chamone, Chequer

2017-05-01

The etiological diagnosis of pleural effusion is a difficult task because the diagnostic tools can only establish a definitive etiological diagnosis in at most 76% of cases. To verify the diagnostic accuracy of the latex agglutination test (LAT) for the etiological diagnosis of pleural effusions caused by Streptococcus pneumoniae and Haemophilus influenzae type b. After thoracocentesis, paired fresh samples of pleural fluid from 418 children and adolescents were included in this investigation. They were tested blindly and simultaneously through counterimmunoelectrophoresis (CIE) and LAT for both bacteria. Sensitivity, specificity, predictive values and likelihood ratios (LR) were calculated taking CIE as a reference standard. The sensitivity and specificity of LAT was 100% (95% confidence interval, 94.4%-100%) and 83.3% (95% confidence interval, 79.0%-87.0%), respectively, whereas the positive (calculated from Bayes' theorem) and negative predictive values were, respectively, lower than 1% and 100% (95% confidence interval, 98.8%-100%). Positive and negative LR were 6.0 (95% confidence interval, 4.7-7.6) and zero, respectively. Our results suggest that LAT is a useful tool for the etiological diagnosis of pleural effusion. It is a reliable, rapid, simple to perform and shows an excellent yield in our studied population, helping to prescribe appropriate antibiotics for this clinical condition. © 2015 John Wiley & Sons Ltd.

Evaluation of the malaria rapid diagnostic test VIKIA malaria Ag Pf/Pan™ in endemic and non-endemic settings

PubMed Central

2013-01-01

Background Malaria rapid diagnostic tests (RDTs) are a useful tool in endemic malaria countries, where light microscopy is not feasible. In non-endemic countries they can be used as complementary tests to provide timely results in case of microscopy inexperience. This study aims to compare the new VIKIA Malaria Ag Pf/Pan™ RDT with PCR-corrected microscopy results and the commonly used CareStart™ RDT to diagnose falciparum and non-falciparum malaria in the endemic setting of Bamako, Mali and the non-endemic setting of Lyon, France. Methods Blood samples were collected during a 12-months and six-months period in 2011 from patients suspected to have malaria in Lyon and Bamako respectively. The samples were examined by light microscopy, the VIKIA Malaria Ag Pf/Pan™ test and in Bamako additionally with the CareStart™ RDT. Discordant results were corrected by real-time PCR. Sensitivity, specificity, positive predictive value and negative predictive value were used to evaluate test performance. Results Samples of 877 patients from both sites were included. The VIKIA Malaria Ag Pf/Pan™ had a sensitivity of 98% and 96% for Plasmodium falciparum in Lyon and Bamako, respectively, performing similar to PCR-corrected microscopy. Conclusions The VIKIA Malaria Ag Pf/Pan™ performs similar to PCR-corrected microscopy for the detection of P. falciparum, making it a valuable tool in malaria endemic and non-endemic regions. PMID:23742633

Waist-to-Height Ratio: a simple, effective and practical screening tool for childhood obesity and metabolic syndrome.

PubMed

Zhou, Dan; Yang, Min; Yuan, Zhe-Ping; Zhang, Dan-Dan; Liang, Li; Wang, Chun-Lin; Zhang, Shuai; Zhu, Hong-Hong; Lai, Mao-De; Zhu, Yi-Min

2014-10-01

This study aimed to evaluate the diagnostic value of Waist-to-Height Ratio in early detection of obesity and metabolic syndrome in Chinese children and adolescents. A cross-sectional study was conducted in six cities in China in 2010 with 16,914 children and adolescents aged 7-17 years. Participants were randomly divided into the training and testing sets. Diagnostic values were estimated using sensitivity, specificity and areas under receiver operating characteristic curves. The coefficients of variation of Waist-to-Height Ratio among age groups were lower than that of body mass index and waist circumstance. The area under receiver operating characteristic curve of Waist-to-Height Ratio was 0.968 in boys and 0.949 in girls for general obesity evaluation, and 0.983 in boys and 0.984 in girls for central obesity. The optimal cut-offs of Waist-to-Height Ratio were 0.47 in boys and 0.45 in girls in the training set and validated in the testing set. For metabolic syndrome evaluation, the sensitivity and specificity were 0.858 and 0.825 in boys, 0.864 and 0.812 in girls under the suggested cut-offs. Waist-to-Height Ratio was a simple, effective and practical tool for mass screening childhood obesity and metabolic syndrome in China. It will have potential values in public health practice. Copyright © 2014 Elsevier Inc. All rights reserved.

Evaluation of the malaria rapid diagnostic test VIKIA malaria Ag Pf/Pan™ in endemic and non-endemic settings.

PubMed

Eibach, Daniel; Traore, Boubacar; Bouchrik, Mourad; Coulibaly, Boubacar; Coulibaly, Nianégué; Siby, Fanta; Bonnot, Guillaume; Bienvenu, Anne-Lise; Picot, Stéphane

2013-06-06

Malaria rapid diagnostic tests (RDTs) are a useful tool in endemic malaria countries, where light microscopy is not feasible. In non-endemic countries they can be used as complementary tests to provide timely results in case of microscopy inexperience. This study aims to compare the new VIKIA Malaria Ag Pf/Pan™ RDT with PCR-corrected microscopy results and the commonly used CareStart™ RDT to diagnose falciparum and non-falciparum malaria in the endemic setting of Bamako, Mali and the non-endemic setting of Lyon, France. Blood samples were collected during a 12-months and six-months period in 2011 from patients suspected to have malaria in Lyon and Bamako respectively. The samples were examined by light microscopy, the VIKIA Malaria Ag Pf/Pan™ test and in Bamako additionally with the CareStart™ RDT. Discordant results were corrected by real-time PCR. Sensitivity, specificity, positive predictive value and negative predictive value were used to evaluate test performance. Samples of 877 patients from both sites were included. The VIKIA Malaria Ag Pf/Pan™ had a sensitivity of 98% and 96% for Plasmodium falciparum in Lyon and Bamako, respectively, performing similar to PCR-corrected microscopy. The VIKIA Malaria Ag Pf/Pan™ performs similar to PCR-corrected microscopy for the detection of P. falciparum, making it a valuable tool in malaria endemic and non-endemic regions.

Diagnostic Performance of Narrow Band Imaging for Nasopharyngeal Cancer: A Systematic Review and Meta-analysis.

PubMed

Sun, Changling; Zhang, Yayun; Han, Xue; Du, Xiaodong

2018-03-01

Objective The purposes of this study were to verify the effectiveness of the narrow band imaging (NBI) system in diagnosing nasopharyngeal cancer (NPC) as compared with white light endoscopy. Data Sources PubMed, Cochrane Library, EMBASE, CNKI, and Wan Fang databases. Review Methods Data analyses were performed with Meta-Disc. The updated Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess study quality and potential bias. Publication bias was assessed with a Deeks asymmetry test. The registry number of the protocol published on PROSPERO is CRD42015026244. Results This meta-analysis included 10 studies of 1337 lesions. For NBI diagnosis of NPC, the pooled values were as follows: sensitivity, 0.83 (95% CI, 0.80-0.86); specificity, 0.91 (95% CI, 0.89-0.93); positive likelihood ratio, 8.82 (95% CI, 5.12-15.21); negative likelihood ratio, 0.18 (95% CI, 0.12-0.27); and diagnostic odds ratio, 65.73 (95% CI, 36.74-117.60). The area under the curve was 0.9549. For white light endoscopy in diagnosing NPC, the pooled values were as follows: sensitivity, 0.79 (95% CI, 0.75-0.83); specificity, 0.87 (95% CI, 0.84-0.90); positive likelihood ratio, 5.02 (95% CI, 1.99-12.65); negative likelihood ratio, 0.34 (95% CI, 0.24-0.49); and diagnostic odds ratio, 16.89 (95% CI, 5.98-47.66). The area under the curve was 0.8627. The evaluation of heterogeneity, calculated per the diagnostic odds ratio, gave an I 2 of 0.326. No marked publication bias ( P = .68) existed in this meta-analysis. Conclusion The sensitivity and specificity of NBI for the diagnosis of NPC are similar to those of white light endoscopy, and the potential value of NBI for the diagnosis of NPC needs to be validated further.

Walking on thin ice! Identifying methamphetamine “drug mules” on digital plain radiography

PubMed Central

Abdul Rashid, S N; Mohamad Saini, S B; Abdul Hamid, S; Muhammad, S J; Mahmud, R; Thali, M J

2014-01-01

Objective: The purpose of this study was to retrospectively evaluate the sensitivity, specificity and accuracy of identifying methamphetamine (MA) internal payloads in “drug mules” by plain abdominal digital radiography (DR). Methods: The study consisted of 35 individuals suspected of internal MA drug containers. A total of 59 supine digital radiographs were collected. An overall calculation regarding the diagnostic accuracy for all “drug mules” and a specific evaluation concerning the radiological appearance of drug packs as well as the rate of clearance and complications in correlation with the reader's experience were performed. The gold standard was the presence of secured drug packs in the faeces. Results: There were 16 true-positive “drug mules” identified. DR of all drug carriers for Group 1 (forensic imaging experienced readers, n = 2) exhibited a sensitivity of 100%, a mean specificity of 76.3%, positive predictive value (PPV) of 78.5%, negative predictive value (NPV) of 100% and a mean accuracy 87.2%. Group 2 (inexperienced readers, n = 3) showed a lower sensitivity (93.7%), a mean specificity of 86%, a PPV of 86.5%, an NPV of 94.1% and a mean accuracy of 89.5%. The interrater agreement within Group 1 was 0.72 and within Group 2 averaged to 0.79, indicating a fair to very good agreement. Conclusion: DR is a valuable screening tool in cases of MA body packers with huge internal payloads being associated with a high diagnostic insecurity. Diagnostic insecurity on plain films may be overcome by low-dose CT as a cross-sectional imaging modality and addressed by improved radiological education in reporting drug carriers on imaging. Advances in knowledge: Diagnostic signs (double-condom and halo signs) on digital plain radiography are specific in MA “drug mules”, although DR is associated with high diagnostic insecurity and underreports the total internal payload. PMID:24472728

Clinical neurophysiology and quantitative sensory testing in the investigation of orofacial pain and sensory function.

PubMed

Jääskeläinen, Satu K

2004-01-01

Chronic orofacial pain represents a diagnostic and treatment challenge for the clinician. Some conditions, such as atypical facial pain, still lack proper diagnostic criteria, and their etiology is not known. The recent development of neurophysiological methods and quantitative sensory testing for the examination of the trigeminal somatosensory system offers several tools for diagnostic and etiological investigation of orofacial pain. This review presents some of these techniques and the results of their application in studies on orofacial pain and sensory dysfunction. Clinical neurophysiological investigation has greater diagnostic accuracy and sensitivity than clinical examination in the detection of the neurogenic abnormalities of either peripheral or central origin that may underlie symptoms of orofacial pain and sensory dysfunction. Neurophysiological testing may also reveal trigeminal pathology when magnetic resonance imaging has failed to detect it, so these methods should be considered complementary to each other in the investigation of orofacial pain patients. The blink reflex, corneal reflex, jaw jerk, sensory neurography of the inferior alveolar nerve, and the recording of trigeminal somatosensory-evoked potentials with near-nerve stimulation have all proved to be sensitive and reliable in the detection of dysfunction of the myelinated sensory fibers of the trigeminal nerve or its central connections within the brainstem. With appropriately small thermodes, thermal quantitative sensory testing is useful for the detection of trigeminal small-fiber dysfunction (Adelta and C). In neuropathic conditions, it is most sensitive to lesions causing axonal injury. By combining different techniques for investigation of the trigeminal system, an accurate topographical diagnosis and profile of sensory fiber pathology can be determined. Neurophysiological and quantitative sensory tests have already highlighted some similarities among various orofacial pain conditions and have shown heterogeneity within clinical diagnostic categories. With the aid of neurophysiological recordings and quantitative sensory testing, it is possible to approach a mechanism-based classification of orofacial pain.

A Comparative Analysis of the ADOS-G and ADOS-2 Algorithms: Preliminary Findings.

PubMed

Dorlack, Taylor P; Myers, Orrin B; Kodituwakku, Piyadasa W

2018-06-01

The Autism Diagnostic Observation Schedule (ADOS) is a widely utilized observational assessment tool for diagnosis of autism spectrum disorders. The original ADOS was succeeded by the ADOS-G with noted improvements. More recently, the ADOS-2 was introduced to further increase its diagnostic accuracy. Studies examining the validity of the ADOS have produced mixed findings, and pooled relationship trends between the algorithm versions are yet to be analyzed. The current review seeks to compare the relative merits of the ADOS-G and ADOS-2 algorithms, Modules 1-3. Eight studies met inclusion criteria for the review, and six were selected for paired comparisons of the sensitivity and specificity of the ADOS. Results indicate several contradictory findings, underscoring the importance of further study.

Detection of Intestinal Protozoa in the Clinical Laboratory

PubMed Central

McHardy, Ian H.; Wu, Max; Shimizu-Cohen, Robyn; Couturier, Marc Roger

2014-01-01

Despite recent advances in diagnostic technology, microscopic examination of stool specimens remains central to the diagnosis of most pathogenic intestinal protozoa. Microscopy is, however, labor-intensive and requires a skilled technologist. New, highly sensitive diagnostic methods have been developed for protozoa endemic to developed countries, including Giardia lamblia (syn. G. intestinalis/G. duodenalis) and Cryptosporidium spp., using technologies that, if expanded, could effectively complement or even replace microscopic approaches. To date, the scope of such novel technologies is limited and may not include common protozoa such as Dientamoeba fragilis, Entamoeba histolytica, or Cyclospora cayetanensis. This minireview describes canonical approaches for the detection of pathogenic intestinal protozoa, while highlighting recent developments and FDA-approved tools for clinical diagnosis of common intestinal protozoa. PMID:24197877

Detection of intestinal protozoa in the clinical laboratory.

PubMed

McHardy, Ian H; Wu, Max; Shimizu-Cohen, Robyn; Couturier, Marc Roger; Humphries, Romney M

2014-03-01

Despite recent advances in diagnostic technology, microscopic examination of stool specimens remains central to the diagnosis of most pathogenic intestinal protozoa. Microscopy is, however, labor-intensive and requires a skilled technologist. New, highly sensitive diagnostic methods have been developed for protozoa endemic to developed countries, including Giardia lamblia (syn. G. intestinalis/G. duodenalis) and Cryptosporidium spp., using technologies that, if expanded, could effectively complement or even replace microscopic approaches. To date, the scope of such novel technologies is limited and may not include common protozoa such as Dientamoeba fragilis, Entamoeba histolytica, or Cyclospora cayetanensis. This minireview describes canonical approaches for the detection of pathogenic intestinal protozoa, while highlighting recent developments and FDA-approved tools for clinical diagnosis of common intestinal protozoa.

Occupational and Environmental Bronchiolar Disorders

PubMed Central

Cummings, Kristin J.; Kreiss, Kathleen

2015-01-01

Occupational and environmental causes of bronchiolar disorders are recognized on the basis of case reports, case series, and, less commonly, epidemiologic investigations. Pathology may be limited to the bronchioles or also involve other components of the respiratory tract, including the alveoli. A range of clinical, functional, and radiographic findings, including symptomatic disease lacking abnormalities on noninvasive testing, poses a diagnostic challenge and highlights the value of surgical biopsy. Disease clusters in workplaces and communities have identified new etiologies, drawn attention to indolent disease that may otherwise have been categorized as idiopathic, and expanded the spectrum of histopathologic responses to an exposure. More sensitive noninvasive diagnostic tools, evidence-based therapies, and ongoing epidemiologic investigation of at-risk populations are needed to identify, treat, and prevent exposure-related bronchiolar disorders. PMID:26024345

The Alpha-Defensin Immunoassay and Leukocyte Esterase Colorimetric Strip Test for the Diagnosis of Periprosthetic Infection

PubMed Central

Wyatt, M.C.; Beswick, A.D.; Kunutsor, S.K.; Wilson, M.J.; Whitehouse, M.R.; Blom, A.W.

2016-01-01

Background: Synovial biomarkers have recently been adopted as diagnostic tools for periprosthetic joint infection (PJI), but their utility is uncertain. The purpose of this systematic review and meta-analysis was to synthesize the evidence on the accuracy of the alpha-defensin immunoassay and leukocyte esterase colorimetric strip test for the diagnosis of PJI compared with the Musculoskeletal Infection Society diagnostic criteria. Methods: We performed a systematic review to identify diagnostic technique studies evaluating the accuracy of alpha-defensin or leukocyte esterase in the diagnosis of PJI. MEDLINE and Embase on Ovid, ACM, ADS, arXiv, CERN DS (Conseil Européen pour la Recherche Nucléaire Document Server), CrossRef DOI (Digital Object Identifier), DBLP (Digital Bibliography & Library Project), Espacenet, Google Scholar, Gutenberg, HighWire, IEEE Xplore (Institute of Electrical and Electronics Engineers digital library), INSPIRE, JSTOR (Journal Storage), OAlster (Open Archives Initiative Protocol for Metadata Harvesting), Open Content, Pubget, PubMed, and Web of Science were searched for appropriate studies indexed from inception until May 30, 2015, along with unpublished or gray literature. The classification of studies and data extraction were performed independently by 2 reviewers. Data extraction permitted meta-analysis of sensitivity and specificity with construction of receiver operating characteristic curves for each test. Results: We included 11 eligible studies. The pooled diagnostic sensitivity and specificity of alpha-defensin (6 studies) for PJI were 1.00 (95% confidence interval [CI], 0.82 to 1.00) and 0.96 (95% CI, 0.89 to 0.99), respectively. The area under the curve (AUC) for alpha-defensin and PJI was 0.99 (95% CI, 0.98 to 1.00). The pooled diagnostic sensitivity and specificity of leukocyte esterase (5 studies) for PJI were 0.81 (95% CI, 0.49 to 0.95) and 0.97 (95% CI, 0.82 to 0.99), respectively. The AUC for leukocyte esterase and PJI was 0.97 (95% CI, 0.95 to 0.98). There was substantial heterogeneity among studies for both diagnostic tests. Conclusions: The diagnostic accuracy for PJI was high for both tests. Given the limited number of studies and the large cost difference between the tests, more independent research on these tests is warranted. Level of Evidence: Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence. PMID:27307359

Diagnostic performance of semi-quantitative and quantitative stress CMR perfusion analysis: a meta-analysis.

PubMed

van Dijk, R; van Assen, M; Vliegenthart, R; de Bock, G H; van der Harst, P; Oudkerk, M

2017-11-27

Stress cardiovascular magnetic resonance (CMR) perfusion imaging is a promising modality for the evaluation of coronary artery disease (CAD) due to high spatial resolution and absence of radiation. Semi-quantitative and quantitative analysis of CMR perfusion are based on signal-intensity curves produced during the first-pass of gadolinium contrast. Multiple semi-quantitative and quantitative parameters have been introduced. Diagnostic performance of these parameters varies extensively among studies and standardized protocols are lacking. This study aims to determine the diagnostic accuracy of semi- quantitative and quantitative CMR perfusion parameters, compared to multiple reference standards. Pubmed, WebOfScience, and Embase were systematically searched using predefined criteria (3272 articles). A check for duplicates was performed (1967 articles). Eligibility and relevance of the articles was determined by two reviewers using pre-defined criteria. The primary data extraction was performed independently by two researchers with the use of a predefined template. Differences in extracted data were resolved by discussion between the two researchers. The quality of the included studies was assessed using the 'Quality Assessment of Diagnostic Accuracy Studies Tool' (QUADAS-2). True positives, false positives, true negatives, and false negatives were subtracted/calculated from the articles. The principal summary measures used to assess diagnostic accuracy were sensitivity, specificity, andarea under the receiver operating curve (AUC). Data was pooled according to analysis territory, reference standard and perfusion parameter. Twenty-two articles were eligible based on the predefined study eligibility criteria. The pooled diagnostic accuracy for segment-, territory- and patient-based analyses showed good diagnostic performance with sensitivity of 0.88, 0.82, and 0.83, specificity of 0.72, 0.83, and 0.76 and AUC of 0.90, 0.84, and 0.87, respectively. In per territory analysis our results show similar diagnostic accuracy comparing anatomical (AUC 0.86(0.83-0.89)) and functional reference standards (AUC 0.88(0.84-0.90)). Only the per territory analysis sensitivity did not show significant heterogeneity. None of the groups showed signs of publication bias. The clinical value of semi-quantitative and quantitative CMR perfusion analysis remains uncertain due to extensive inter-study heterogeneity and large differences in CMR perfusion acquisition protocols, reference standards, and methods of assessment of myocardial perfusion parameters. For wide spread implementation, standardization of CMR perfusion techniques is essential. CRD42016040176 .

Advances in the Diagnosis of Human Opisthorchiasis: Development of Opisthorchis viverrini Antigen Detection in Urine

PubMed Central

Duenngai, Kunyarat; Wangboon, Chompunoot; Sithithaworn, Jiraporn; Watwiengkam, Nattaya; Namwat, Nisana; Techasen, Anchalee; Loilome, Watcharin; Yongvanit, Puangrat; Loukas, Alex; Sithithaworn, Paiboon; Bethony, Jeffrey M.

2015-01-01

Background Many strategies to control opisthorchiasis have been employed in Thailand, but not in the other neighbouring countries. Specific control methods include mass drug administration (MDA) and health education to reduce raw fish consumption. These control efforts have greatly shifted the epidemiology of Opisthorchis viverrini (OV) infection over the last decade from presenting as densely concentrated "heavy" infections in single villages to widespread "light" OV infections distributed over wide geographical areas. Currently, the "gold standard" detection method for OV infection is formalin ethyl-acetate concentration technique (FECT), which has limited diagnostic sensitivity and diagnostic specificity for light OV infections, with OV eggs often confused with eggs of minute intestinal flukes (MIFs) in feces. In this study, we developed and evaluated the diagnostic performance of a monoclonal antibody-based enzyme-linked immunosorbent assay for the measurement of OV excretory-secretory (ES) antigens in urine (urine OV-ES assay) for the diagnosis of opisthorchiasis compared to the gold standard detection FECT method. Methodology We tested several methods for pre-treating urine samples prior to testing the diagnostic performance of the urine OV-ES assay. Using trichloroacetic acid (TCA) pre-treated urine, we compared detection and quantification of OV infection using the urine OV-ES assay versus FECT in OV-endemic areas in Northeastern Thailand. Receiver operating characteristic (ROC) curves were used to determine the diagnostic sensitivity and specificity of the urine OV-ES assay using TCA pre-treated urine, and to establish diagnostic positivity thresholds. The Positive Predictive Value as well as the likelihood of obtaining a positive test result (LR+) or a negative test result (LR-) were calculated for the established diagnostic positivity threshold. Diagnostic risks (Odds Ratios) were estimated using logistic regression. Results When urine samples were pre-treated with TCA prior to use in the urine OV-ES assay, the analytical sensitivity was significantly improved. Using TCA pre-treatment of urine, the urine OV-ES assay had a limit of detection (LoD) of 39 ng/ml compared to the LoD of 52 ng/mL reported for coprological antigen detection methods. Similarly, the urine OV-ES assay correlated significantly with intensity of OV infection as measured by FECT. The urine OV-ES assay was also able to detect 28 individuals as positive from the 63 (44.4%) individuals previously determined to be negative using FECT. The likelihood of a positive diagnosis of OV infection by urine OV-ES assay increased significantly with the intensity of OV infection as determined by FECT. With reference to FECT, the sensitivity and specificity of the urine OV-ES assay was 81% and 70%, respectively. Conclusion The detection of OV-infection by the urine OV-ES assay showed much greater diagnostic sensitivity and diagnostic specificity than the current "gold standard" FECT method for the detection and quantification of OV infection. Due to its ease-of-use, and noninvasive sample collection (urine), the urine OV-ES assay offers the potential to revolutionize the diagnosis of liver fluke infection and provide an effective tool for control and elimination of these tumorigenic parasites. PMID:26485024

Frailty Screening Tools for Elderly Patients Incident to Dialysis.

PubMed

van Loon, Ismay N; Goto, Namiko A; Boereboom, Franciscus T J; Bots, Michiel L; Verhaar, Marianne C; Hamaker, Marije E

2017-09-07

A geriatric assessment is an appropriate method for identifying frail elderly patients. In CKD, it may contribute to optimize personalized care. However, a geriatric assessment is time consuming. The purpose of our study was to compare easy to apply frailty screening tools with the geriatric assessment in patients eligible for dialysis. A total of 123 patients on incident dialysis ≥65 years old were included <3 weeks before to ≤2 weeks after dialysis initiation, and all underwent a geriatric assessment. Patients with impairment in two or more geriatric domains on the geriatric assessment were considered frail. The diagnostic abilities of six frailty screening tools were compared with the geriatric assessment: the Fried Frailty Index, the Groningen Frailty Indicator, Geriatric8, the Identification of Seniors at Risk, the Hospital Safety Program, and the clinical judgment of the nephrologist. Outcome measures were sensitivity, specificity, positive predictive value, and negative predictive value. In total, 75% of patients were frail according to the geriatric assessment. Sensitivity of frailty screening tools ranged from 48% (Fried Frailty Index) to 88% (Geriatric8). The discriminating features of the clinical judgment were comparable with the other screening tools. The Identification of Seniors at Risk screening tool had the best discriminating abilities, with a sensitivity of 74%, a specificity of 80%, a positive predictive value of 91%, and a negative predictive value of 52%. The negative predictive value was poor for all tools, which means that almost one half of the patients screened as fit (nonfrail) had two or more geriatric impairments on the geriatric assessment. All frailty screening tools are able to detect geriatric impairment in elderly patients eligible for dialysis. However, all applied screening tools, including the judgment of the nephrologist, lack the discriminating abilities to adequately rule out frailty compared with a geriatric assessment. Copyright © 2017 by the American Society of Nephrology.

Glaucoma diagnostics.

PubMed

Geimer, Sabina Andersson

2013-02-01

This thesis addresses several aspects of glaucoma diagnostics from both a clinical and a screening perspective. New instruments for diagnosing glaucoma have been developed over the past years, but little information is available regarding their performance as screening methods and their usefulness in ordinary clinical practice. PURPOSE OF THE RESEARCH UNDERLYING THIS THESIS:  The objectives of this research were as follows: to compare the accuracy of results of analysis of the optic nerve head (ONH) achieved by computerized imaging using the Heidelberg Retina Tomograph (HRT) and by subjective assessment performed by physicians with different degrees of experience of glaucoma (paper III); to evaluate the effect of a continuous medical education (CME) lecture on subjective assessment of the ONH for diagnosis of glaucoma (paper II); to investigate subjective assessment of perimetric test results by physicians with varying knowledge of glaucoma with a trained artificial neural network (ANN) and to compare the certainty of the classifications (paper IV); and to compare the diagnostic performance of time-domain Stratus optical coherence tomography (OCT) with that of spectral-domain Cirrus OCT (paper I), frequency doubling technology (FDT) screening perimetry and scanning laser polarimetry with the GDx variable corneal compensator (VCC) in a random population-based sample and in patients with glaucoma of varying disease severity.   In evaluation of the ONH, use of the HRT statistical tools, Moorfields regression analysis (MRA) and the Glaucoma Probability Score (GPS) was compared with subjective assessment performed by 45 physicians. Optic nerve head images and photographs from 138 healthy and 97 glaucoma subjects were included. The sensitivity of MRA was higher (87-94%) than that of the average physician (62-82%), considerably greater than that of ophthalmologists with subspecialties other than glaucoma (53-77%) and non-significantly better than that of glaucoma experts (72-88%). Sensitivity achieved by GPS (79-93%) was also greater than that of the average physician. MRA correctly classified all eyes with advanced glaucomatous visual field defects, a result that was not achieved by GPS or even by the glaucoma experts. In eyes with small discs, MRA sensitivity (88%) was comparable with that of glaucoma experts (85%) and much better than that of GPS (50%). Also, the group comprising all physicians provided specificity (75-92%) similar to that of both MRA (69 - 86%) and GPS (72-94%) (Andersson et al. 2011a). A 1-hr CME lecture on ONH assessment led to a significant improvement in sensitivity (from 70% to 80%) and a significant decrease in uncertain assessments (from 22% to 13%), whereas specificity remained unchanged (68%) (Andersson et al. 2011b). A rise in sensitivity was seen in all subgroups of physicians, including glaucoma experts. Thirty physicians assessing standard automated perimetry (SAP) test results as Humphrey Field Analyzer single-field analysis printouts with full StatPac information from 99 patients with glaucoma and 66 healthy subjects were compared with a trained ANN regarding diagnostic performance. ANN reached significantly higher sensitivity (93%) than the average physician (83%), whereas specificity was similar for these two groups (91% and 90%, respectively). Diagnostic accuracy was similar among the different groups of physicians and seemingly rather independent of experience. Sensitivity ranged from 82% in the subgroup of other subspecialists to 87% in the glaucoma expert group, and specificity ranged from 88% among general ophthalmologists to 91% for glaucoma experts. The ANN attained certainty of classification that was in parity with that provided by the glaucoma experts and did not make any completely incorrect classifications of the visual fields (i.e. erroneous classifications were in the borderline zone) (Andersson et al. 2012). From a population-based randomly selected sample (n=308) of older subjects (aged ≥ 50 years) living in southern Sweden, 170 subjects underwent a comprehensive examination that included Stratus OCT, Cirrus OCT, an FDT screening programme and the GDx VCC. The same test protocol was applied to 138 randomized clinical patients with different stages of glaucoma. In the population-based sample, both Stratus and Cirrus OCT showed high diagnostic accuracy with area under the receiver-operating curve (aROC) values close to 1.0 (Bengtsson et al. 2012). Both OCT instruments correctly classified all of the clinical glaucoma patients with advanced disease. FDT screening showed high sensitivity (91%) but erroneously gave normal test results for some eyes with advanced disease. GDx VCC had lower sensitivity (73-92%) and also led to a large proportion of examinations with an atypical retardation pattern that is known to affect the diagnostic efficiency of this instrument.   The HRT MRA performed better than most physicians and was consistent with the glaucoma experts. These results suggest that MRA can be a valuable tool for diagnosing glaucoma in ordinary practice, particularly when only a few glaucoma experts are available. Even though MRA provided 100% sensitivity in eyes with advanced glaucoma, it probably does not offer sufficient specificity to make it suitable as a screening method. Continuing medical education on ONH analysis had a small, but positive effect on diagnostic accuracy for glaucoma. An ANN trained to classify visual fields seemed to perform at least as well as most of the participating physicians, whose performances were remarkably similar regardless of their level of experience. This indicates that available tools for interpreting SAP findings are helpful in assessments of visual field test results. However, SAP is associated with learning effects (Heijl et al. 1989) that may entail low specificity for untrained subjects, and hence, it is not an ideal screening method for glaucoma. By comparison, the screening test of FDT is rapid and easy, but it is probably less suitable for screening purpose, because some eyes with advanced glaucoma were missed in this investigation. GDx VCC images for a relatively large number of eyes could not be analysed and is thus not appropriate for screening. The OCT instruments offer both high sensitivity and high specificity, and all eyes with advanced disease were correctly classified as glaucomatous in this evaluation. However, these instruments are still expensive and require special operator skills. Additional development to obtain OCT instrument that is more compact, easier to use and less expensive might render such tomography suitable as a screening tool for glaucoma. © 2013 The Author. Acta Ophthalmologica © 2013 Acta Ophthalmologica Scandinavica Foundation.

The RIPASA score is sensitive and specific for the diagnosis of acute appendicitis in a western population.

PubMed

Malik, Muhammad Usman; Connelly, Tara M; Awan, Faisal; Pretorius, Frederik; Fiuza-Castineira, Constantino; El Faedy, Osama; Balfe, Paul

2017-04-01

The definitive diagnosis of acute appendicitis (AA) requires histopathological examination. Various clinical diagnostic scoring systems attempt to reduce negative appendectomy rates. The most commonly used in Western Europe and the USA is the Alvarado score. The Raja Isteri Pengiran Anak Saleha appendicitis (RIPASA) score achieves better sensitivity and specificity in Asian and Middle Eastern populations. We aimed to determine the diagnostic accuracy of the RIPASA score in Irish patients with AA. All patients who presented to our institution with right iliac fossa pain and clinically suspected AA between January 1 and December 31, 2015, were indentified from our hospital inpatient enquiry database and retrospectively studied. Operating theatre records and histology reports confirmed those who underwent a non-elective operative procedure and the presence or absence of AA. SPSS version 22 was used for statistical analysis. Standard deviation is provided where appropriate. Two hundred eight patients were included in the study (106/51% male, mean age 22.7 ± 9.2 years). One hundred thirty-five (64.9%) had histologically confirmed AA (mean symptom duration = 36.19 ± 15.90 h). At a score ≥7.5, the previously determined score most likely associated with AA in Eastern populations, the RIPASA scoring system demonstrated a sensitivity of 85.39%, specificity of 69.86%, positive predictive value of 84.06%, negative predictive value of 72.86% and diagnostic accuracy of 80% in our cohort. The RIPASA score is a useful tool to aid in the diagnosis of acute appendicitis in the Irish population. A score of ≥7.5 provides sensitivity and specificity exceeding that previously documented for the Alvarado score in Western populations. WHAT DOES THIS PAPER ADD TO THE LITERATURE?: This is the first study evaluating the utility of the RIPASA score in predicting acute appendicitis in a Western population. At a value of 7.5, a cut-off score suggestive of appendicitis in the Eastern population, RIPASA demonstrated a high-sensitivity, specificity, positive predictive value and diagnostic accuracy in our cohort and was more accurate than the commonly used Alvarado score.

Diagnostic yield of endobronchial ultrasound-guided transbronchial needle aspiration for mediastinal staging in lung cancer*

PubMed Central

Fernández-Bussy, Sebastián; Labarca, Gonzalo; Canals, Sofia; Caviedes, Iván; Folch, Erik; Majid, Adnan

2015-01-01

OBJECTIVE: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive diagnostic test with a high diagnostic yield for suspicious central pulmonary lesions and for mediastinal lymph node staging. The main objective of this study was to describe the diagnostic yield of EBUS-TBNA for mediastinal lymph node staging in patients with suspected lung cancer. METHODS: Prospective study of patients undergoing EBUS-TBNA for diagnosis. Patients ≥ 18 years of age were recruited between July of 2010 and August of 2013. We recorded demographic variables, radiological characteristics provided by axial CT of the chest, location of the lesion in the mediastinum as per the International Association for the Study of Lung Cancer classification, and definitive diagnostic result (EBUS with a diagnostic biopsy or a definitive diagnostic method). RESULTS: Our analysis included 354 biopsies, from 145 patients. Of those 145 patients, 54.48% were male. The mean age was 63.75 years. The mean lymph node size was 15.03 mm, and 90 lymph nodes were smaller than 10.0 mm. The EBUS-TBNA method showed a sensitivity of 91.17%, a specificity of 100.0%, and a negative predictive value of 92.9%. The most common histological diagnosis was adenocarcinoma. CONCLUSIONS: EBUS-TBNA is a diagnostic tool that yields satisfactory results in the staging of neoplastic mediastinal lesions. PMID:26176519

KS-Detect – Validation of Solar Thermal PCR for the Diagnosis of Kaposi’s Sarcoma Using Pseudo-Biopsy Samples

PubMed Central

Snodgrass, Ryan; Gardner, Andrea; Jiang, Li; Fu, Cheng; Cesarman, Ethel; Erickson, David

2016-01-01

Resource-limited settings present unique engineering challenges for medical diagnostics. Diagnosis is often needed for those unable to reach central healthcare systems, making portability and independence from traditional energy infrastructure essential device parameters. In 2014, our group presented a microfluidic device that performed a solar-powered variant of the polymerase chain reaction, which we called solar thermal PCR. In this work, we expand on our previous effort by presenting an integrated, portable, solar thermal PCR system targeted towards the diagnosis of Kaposi’s sarcoma. We call this system KS-Detect, and we now report the system’s performance as a diagnostic tool using pseudo-biopsy samples made from varying concentrations of human lymphoma cell lines positive for the KS herpesvirus (KSHV). KS-Detect achieved 83% sensitivity and 70% specificity at high (≥10%) KSHV+ cell concentrations when diagnosing pseudo-biopsy samples by smartphone image. Using histology, we confirm that our prepared pseudo-biopsies contain similar KSHV+ cell concentrations as human biopsies positive for KS. Through our testing of samples derived from human cell lines, we validate KS-Detect as a viable, portable KS diagnostic tool, and we identify critical engineering considerations for future solar-thermal PCR devices. PMID:26799834

Improving early detection of childhood depression in mental health care: the Children׳s Depression Screener (ChilD-S).

PubMed

Allgaier, Antje-Kathrin; Krick, Kathrin; Opitz, Ansgar; Saravo, Barbara; Romanos, Marcel; Schulte-Körne, Gerd

2014-07-30

Diagnosing childhood depression can pose a challenge, even for mental health specialists. Screening tools can aid clinicians within the initial step of the diagnostic process. For the first time, the Children׳s Depression Screener (ChilD-S) is validated in a mental health setting as a novel field of application beyond the previously examined pediatric setting. Based on a structured interview, DSM-IV-TR diagnoses of depression were made for 79 psychiatric patients aged 9-12, serving as the gold standard for validation. For assessing criterion validity, receiver operating characteristic (ROC) curves were calculated. Point prevalence of major depression and dysthymia was 28%. Diagnostic accuracy in terms of the area under the ROC curve was high (0.97). At the optimal cut-off point ≥12 according to the Youden׳s index, sensitivity was 0.91 and specificity was 0.81. The findings suggest that the ChilD-S is not only a valid screening instrument for childhood depression in pediatric care but also in mental health settings. As a brief tool it can easily be implemented into daily clinical practice of mental health professionals facilitating the diagnostic process, especially in case of comorbid depression. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Malaria attacks due to P. vivax or P. ovale in two French military teaching hospitals (2000 to 2009).

PubMed

Demaison, X; Rapp, C; de Laval, F; Simon, F

2013-04-01

Non-falciparum malaria is less studied than Plasmodium falciparum malaria, both in endemic and non-endemic zones. A retrospective study was made of the medical files of patients managed for attacks of malaria due to Plasmodium vivax or Plasmodium ovale, between 2000 and 2009, in two French military teaching hospitals. Seventy-five percent of attacks occurred after a stay in French Guiana, in the Comoros Archipelago, or in the Ivory Coast Republic. The most frequent symptoms two months after coming back were a flu-like syndrome with headaches, and occasional digestive symptoms, without any difference between the first attack and recurrence. One third of patients presented with anemia, 78% with thrombocytopenia, and 12% with liver dysfunction. This study was the most important made in France on imported non-falciparum malaria. Military patients and immigrants accounted for a majority of patients due to the specificity of military hospitals and local recruitment. Clinical and biological features were not specific and did not allow guiding the diagnosis. Diagnostic tools were less sensitive for P. ovale. Patient management could be optimized by more efficient diagnostic tools, specific guidelines for the diagnostic and therapeutic management, and a dedicated medical training for family practitioners as well as hospitals practice. Copyright © 2013. Published by Elsevier SAS.

Selection and application of familiar and novel tools in patients with left and right hemispheric stroke: Psychometrics and normative data.

PubMed

Buchmann, Ilka; Randerath, Jennifer

2017-09-01

Frequently left brain damage (LBD) leads to limb apraxia, a disorder that can affect tool-use. Despite its impact on daily life, classical tests examining the pantomime of tool-use and imitation of gestures are seldom applied in clinical practice. The study's aim was to present a diagnostic approach which appears more strongly related to actions in daily life in order to sensitize applicants and patients about the relevance of the disorder before patients are discharged. Two tests were introduced that evaluate actual tool selection and tool-object-application: the Novel Tools (NTT) and the Familiar Tools (FTT) Test (parts of the DILA-S: Diagnostic Instrument for Limb Apraxia - Short Version). Normative data in healthy subjects (N = 82) was collected. Then the tests were applied in stroke patients with unilateral left brain damage (LBD: N = 33), a control right brain damage group (RBD: N = 20) as well as healthy age and gender matched controls (CL: N = 28, and CR, N = 18). The tests showed appropriate interrater-reliability and internal consistency as well as concurrent and divergent validity. To examine criterion validity based on the well-known left lateralization of limb apraxia, group comparisons were run. As expected, the LBD group demonstrated a high prevalence of tool-use apraxia (NTT: 36.4%, FTT: 48.5%) ranging from mild to severe impairment and scored worse than their control group (CL). A few RBD patients did demonstrate impairments in tool-use (NTT: 15%, FTT: 15%). On a group level they did not differ from their healthy controls (CR). Further, it was demonstrated that the selection and application of familiar and novel tools can be impaired selectively. Our study results suggest that real tool-use tests evaluating tool selection and tool application should be considered for standard diagnosis of limb apraxia in left as well as right brain damaged patients. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Triage tools for detecting cervical spine injury in pediatric trauma patients.

PubMed

Slaar, Annelie; Fockens, M M; Wang, Junfeng; Maas, Mario; Wilson, David J; Goslings, J Carel; Schep, Niels Wl; van Rijn, Rick R

2017-12-07

Pediatric cervical spine injury (CSI) after blunt trauma is rare. Nonetheless, missing these injuries can have severe consequences. To prevent the overuse of radiographic imaging, two clinical decision tools have been developed: The National Emergency X-Radiography Utilization Study (NEXUS) criteria and the Canadian C-spine Rule (CCR). Both tools are proven to be accurate in deciding whether or not diagnostic imaging is needed in adults presenting for blunt trauma screening at the emergency department. However, little information is known about the accuracy of these triage tools in a pediatric population. To determine the diagnostic accuracy of the NEXUS criteria and the Canadian C-spine Rule in a pediatric population evaluated for CSI following blunt trauma. We searched the following databases to 24 February 2015: CENTRAL, MEDLINE, MEDLINE Non-Indexed and In-Process Citations, PubMed, Embase, Science Citation Index, ProQuest Dissertations & Theses Database, OpenGrey, ClinicalTrials.gov, World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects, the Health Technology Assessment, and the Aggressive Research Intelligence Facility. We included all retrospective and prospective studies involving children following blunt trauma that evaluated the accuracy of the NEXUS criteria, the Canadian C-spine Rule, or both. Plain radiography, computed tomography (CT) or magnetic resonance imaging (MRI) of the cervical spine, and follow-up were considered as adequate reference standards. Two review authors independently assessed the quality of included studies using the QUADAS-2 checklists. They extracted data on study design, patient characteristics, inclusion and exclusion criteria, clinical parameters, target condition, reference standard, and the diagnostic two-by-two table. We calculated and plotted sensitivity, specificity and negative predictive value in ROC space, and constructed forest plots for visual examination of variation in test accuracy. Three cohort studies were eligible for analysis, including 3380 patients ; 96 children were diagnosed with CSI. One study evaluated the accuracy of the Canadian C-spine Rule and the NEXUS criteria, and two studies evaluated the accuracy of the NEXUS criteria. The studies were of moderate quality. Due to the small number of included studies and the diverse outcomes of those studies, we could not describe a pooled estimate for the diagnostic test accuracy. The sensitivity of the NEXUS criteria of the individual studies was 0.57 (95% confidence interval (CI) 0.18 to 0.90), 0.98 (95% CI 0.91 to 1.00) and 1.00 (95% CI 0.88 to 1.00). The specificity of the NEXUS criteria was 0.35 (95% CI 0.25 to 0.45), 0.54 (95% CI 0.45 to 0.62) and 0.2 (95% CI 0.18 to 0.21). For the Canadian C-spine Rule the sensitivity was 0.86 (95% CI 0.42 to 1.00) and specificity was 0.15 (95% CI 0.08 to 0.23). Since the quantity of the data was small we were not able to investigate heterogeneity. There are currently few studies assessing the diagnostic test accuracy of the NEXUS criteria and CCR in children. At the moment, there is not enough evidence to determine the accuracy of the Canadian C-spine Rule to detect CSI in pediatric trauma patients following blunt trauma. The confidence interval of the sensitivity of the NEXUS criteria between the individual studies showed a wide range, with a lower limit varying from 0.18 to 0.91 with a total of four false negative test results, meaning that if physicians use the NEXUS criteria in children, there is a chance of missing CSI. Since missing CSI could have severe consequences with the risk of significant morbidity, we consider that the NEXUS criteria are at best a guide to clinical assessment, with current evidence not supporting strict or protocolized adoption of the tool into pediatric trauma care. Moreover, we have to keep in mind that the sensitivity differs among several studies, and individual confidence intervals of these studies show a wide range. Our main conclusion is therefore that additional well-designed studies with large sample sizes are required to better evaluate the accuracy of the NEXUS criteria or the Canadian C-spine Rule, or both, in order to determine whether they are appropriate triage tools for the clearance of the cervical spine in children following blunt trauma.

A sensitive one-step TaqMan amplification approach for detection of rubella virus clade I and II genotypes in clinical samples.

PubMed

Claus, C; Bergs, S; Emmrich, N C; Hübschen, J M; Mankertz, A; Liebert, U G

2017-02-01

Although teratogenic rubella virus (RV) causes a vaccine-preventable disease, it is still endemic in several countries worldwide. Thus, there is a constant risk of RV importation into non-endemic areas. RV monitoring, especially during measles and Zika virus outbreaks, requires reliable diagnostic tools. For this study, a TaqMan-based one-step reverse transcription-quantitative PCR (RT-qPCR) assay, with the p90 gene as a novel and so far unexplored target for detection of clade I and II genotypes, was developed and evaluated. Automated nucleic acid extraction was carried out. Performance characteristics of the TaqMan RT-qPCR assay were determined for a RV plasmid standard and RNA extracted from virus-infected cell culture supernatants representing clade I and II genotypes. Diagnostic specificity and sensitivity were validated against other RNA and DNA viruses, relevant for RV diagnostic approaches and for RV-positive clinical samples, respectively. The assay is specific and highly sensitive with a limit of detection as low as five to one copies per reaction or 200 infectious virus particles per ml. The coefficients of variation (CV) were specified as intra- (within one run) and inter- (between different runs) assay variation, and calculated based on the standard deviations for the obtained Ct values of the respective samples. Intra- and inter-assay CV values were low, with a maximum of 3.4% and 2.4%, respectively. The assay was shown to be suitable and specific for the analysis of clinical samples. With p90 as a novel target, the highly sensitive and specific TaqMan assay outlined in this study is suitable for RV diagnosis worldwide.

An assessment of Movement Disorder Society Task Force diagnostic criteria for mild cognitive impairment in Parkinson's disease.

PubMed

Uysal-Cantürk, P; Hanağası, H A; Bilgiç, B; Gürvit, H; Emre, M

2018-01-01

Cognitive impairment is one of the most disabling non-motor symptoms of Parkinson's disease. Mild cognitive impairment constitutes a major risk for the development of Parkinson's disease dementia in the course of the disease. A Movement Disorder Society Task Force proposed diagnostic criteria for mild cognitive impairment in Parkinson's disease (PD-MCI), comprising two operational levels: Level I and Level II. The objective of our study was to test the accuracy of Level I versus Level II diagnostic criteria. Eighty-six consecutive patients with Parkinson's disease were screened and 68 patients without dementia or depression were included in the study. We used the Montreal Cognitive Assessment, Mini-Mental State Examination and Addenbrooke's Cognitive Evaluation-R screening tools for Level I and an extensive neuropsychological battery for Level II assessment. We first diagnosed PD-MCI on the basis of Level II assessment and then calculated sensitivity, specificity and area under the receiver-operator characteristics curve, comparing the performance of the three screening batteries. None of the three screening batteries proposed for Level I assessment provided satisfactory combined sensitivity and specificity for detecting PD-MCI, and their performance was similar. Using the Level II criteria, 29 patients (43%) were diagnosed as having PD-MCI. Lowest cut-off levels that provided at least 80% sensitivity were 24 for the Montreal Cognitive Assessment, 29 for the Mini-Mental State Examination and 87 for the Addenbrooke's Cognitive Evaluation-R. However, specificity levels were below 80% at these cut-off levels. We conclude that Level I assessment alone using screening batteries is not sufficiently sensitive/specific to detect PD-MCI. © 2017 EAN.

Rapid and quantitative detection of zoonotic influenza A virus infection utilizing coumarin-derived dendrimer-based fluorescent immunochromatographic strip test (FICT).

PubMed

Yeo, Seon-Ju; Huong, Dinh Thi; Hong, Nguyen Ngoc; Li, Chun-Ying; Choi, Kyunghan; Yu, Kyoungsik; Choi, Du-Young; Chong, Chom-Kyu; Choi, Hak Soo; Mallik, Shyam Kumar; Kim, Hak Sung; Sung, Haan Woo; Park, Hyun

2014-01-01

Great efforts have been made to develop robust signal-generating fluorescence materials which will help in improving the rapid diagnostic test (RDT) in terms of sensitivity and quantification. In this study, we developed coumarin-derived dendrimer-based fluorescent immunochromatographic strip test (FICT) assay with enhanced sensitivity as a quantitative diagnostic tool in typical RDT environments. The accuracy of the proposed FICT was compared with that of dot blot immunoassay techniques and conventional RDTs. Through conjugation of coumarin-derived dendrimers with latex beads, fluorescent emission covering broad output spectral ranges was obtained which provided a distinct advantage of easy discrimination of the fluorescent emission of the latex beads with a simple insertion of a long-pass optical filter away from the excitation wavelength. The newly developed FICT assay was able to detect 100 ng/10 μL of influenza A nucleoprotein (NP) antigen within 5 minutes, which corresponded to 2.5-fold higher sensitivity than that of the dot blot immunoassay or conventional RDTs. Moreover, the FICT assay was confirmed to detect at least four avian influenza A subtypes (H5N3, H7N1, H7N7, and H9N2). On applying the FICT to the clinical swab samples infected with respiratory viruses, our FICT assay was confirmed to differentiate influenza H1N1 infection from other respiratory viral diseases. These data demonstrate that the proposed FICT assay is able to detect zoonotic influenza A viruses with a high sensitivity, and it enables the quantitation of the infection intensity by providing the numerical diagnostic values; thus demonstrating enhanced detectability of influenza A viruses.

Comparison of four rapid diagnostic tests, ELISA, microscopy and PCR for the detection of Giardia lamblia, Cryptosporidium spp. and Entamoeba histolytica in feces.

PubMed

Van den Bossche, Dorien; Cnops, Lieselotte; Verschueren, Jacob; Van Esbroeck, Marjan

2015-03-01

Microscopy is the diagnostic reference standard for the detection of parasites, but it is labor-intensive and requires experience. Rapid diagnostic tests (RDTs) can provide an alternative to microscopy. RDTs from four different manufacturers were compared to enzyme-linked immunosorbent assay (ELISA), microscopy and/or parasite-specific real-time PCR: ImmunoCardSTAT!®CGE (Meridian Bioscience Inc., Cincinnati, Ohio, USA) (A), Crypto/Giardia Duo-Strip (Coris Bioconcepts, Gembloux, Belgium) (B), RIDA®QUICK Cryptosporidium/Giardia/Entamoeba Combi (R-BioPharm, Darmstadt, Germany) (C) and Giardia/Cryptosporidium Quik Chek (Techlab Inc., Blacksburg, Virginia, USA) (D). Thirty frozen samples were analyzed retrospectively. For Giardia lamblia (n=12) and Cryptosporidium (n=12) sensitivities ranged from 58% (B), over 83% (A, C) to 100% (D) and from 92% (B) to 100% (A, C, D), respectively. Specificity for both G. lamblia and Cryptosporidium was 100% for all RDT brands. Sensitivity for Entamoeba histolytica (n=5) was 100%, while specificity reached 80% (A) to 88% (C). In a prospective study, fresh samples were tested. For G. lamblia (n=30), sensitivity ranged from 66% (B), over 79% (A) and 83% (C) to 100% (D) and specificity varied between 94% (D) and 100% (A, B, C). For Cryptosporidium (n=3), sensitivity was 100% for all brands except (B) (67%) and specificities were 95% (A, B), 98% (C) and 100% (D). E. histolytica (n=1) was detected by both (A) and (C), while specificity was 81% and 87% respectively. RDTs can be a valuable tool when microscopic expertise is poor and in remote and outbreak settings where other techniques are often not available and rapid diagnosis is required. Copyright © 2015 Elsevier B.V. All rights reserved.

Development and evaluation of a brief self-completed family history screening tool for common chronic disease prevention in primary care

PubMed Central

Walter, Fiona M; Prevost, A Toby; Birt, Linda; Grehan, Nicola; Restarick, Kathy; Morris, Helen C; Sutton, Stephen; Rose, Peter; Downing, Sarah; Emery, Jon D

2013-01-01

Background Family history is an important risk factor for many common chronic diseases, but it remains underutilised for diagnostic assessment and disease prevention in routine primary care. Aim To develop and validate a brief self-completed family history questionnaire (FHQ) for systematic primary care assessment for family history of diabetes, ischaemic heart disease, breast cancer, and colorectal cancer. Design and setting Two-stage diagnostic validation study in 10 general practices in eastern England. Method Participants aged 18–50 years were identified via random sampling from electronic searches of general practice records. Participants completed a FHQ then had a three-generational ‘gold standard’ pedigree taken, to determine disease risk category. In stage 1, the FHQ comprised 12 items; in stage 2 the shorter 6-item FHQ was validated against the same ‘gold standard’. Results There were 1147 participants (stage 1: 618; stage 2: 529). Overall, 32% were at increased risk of one or more marker conditions (diabetes 18.9%, ischaemic heart disease 13.3%, breast cancer 6.2%, colorectal cancer 2.2%). The shorter 6-item FHQ performed very well for all four conditions: pooled data from both stages show diabetes, sensitivity = 98%, specificity = 94%; ischaemic heart disease, sensitivity = 93%, specificity = 81%; breast cancer, sensitivity = 81%, specificity = 83%; colorectal cancer, sensitivity = 96%, specificity = 88%, with an area under the receiver operating characteristic curve of 0.90 for males and 0.89 for females. Conclusion This brief self-completed FHQ shows good diagnostic accuracy for identifying people at higher risk of four common chronic diseases. It could be used in routine primary care to identify patients who would be most likely to benefit from a more detailed pedigree and risk assessment, and consequent management strategies. PMID:23735410

Sensitivity and specificity of the Geriatric Anxiety Inventory and the Hospital Anxiety and Depression Scale in the detection of anxiety disorders in older people with chronic obstructive pulmonary disease.

PubMed

Cheung, Gary; Patrick, Colin; Sullivan, Glenda; Cooray, Manisha; Chang, Catherina L

2012-01-01

Anxiety and depression are prevalent in patients with chronic obstructive pulmonary disease (COPD). This study evaluates the sensitivity and specificity of two self-administered anxiety rating scales in older people with COPD. The Geriatric Anxiety Inventory (GAI) and the Hospital Anxiety and Depression Scale (HADS) are established useful screening tools but they have not been previously validated in this population. Older people with COPD completed the GAI and the HADS along with a structured diagnostic psychiatric interview, the Mini International Neuropsychiatric Interview (MINI). The outcomes of both rating scales were compared against the diagnosis of anxiety disorders based on the MINI. Receiver operating characteristic (ROC) curves were used to identify the optimal diagnostic cut points for each scale. Fourteen (25.5%) of the 55 participants, were diagnosed with an anxiety disorder. Mean GAI and HADS-anxiety subscale scores were significantly higher in subjects with an anxiety disorder than those without the diagnosis (p = 0.002 and 0.005 respectively). Both scales demonstrated moderate diagnostic value (area under the ROC curve was 0.83 for GAI and 0.79 for HADS). Optimal cut points were ≥3 (GAI) and ≥4 (HADS-anxiety subscale). At these cut-points, the GAI had a sensitivity of 85.7%, specificity of 78.0% and the HADS had a sensitivity of 78.6%, specificity 70.7%. Our results support the use of the GAI and HADS as screening instruments for anxiety disorders in older people with COPD. The optimal cut points in this population were lower than previously recommended for both rating scales. The results of this study should be replicated before these cut points can be recommended for general use in older people with COPD.

Selective parathyroid venous sampling in primary hyperparathyroidism: A systematic review and meta-analysis.

PubMed

Ibraheem, Kareem; Toraih, Eman A; Haddad, Antoine B; Farag, Mahmoud; Randolph, Gregory W; Kandil, Emad

2018-05-14

Minimally invasive parathyroidectomy requires accurate preoperative localization techniques. There is considerable controversy about the effectiveness of selective parathyroid venous sampling (sPVS) in primary hyperparathyroidism (PHPT) patients. The aim of this meta-analysis is to examine the diagnostic accuracy of sPVS as a preoperative localization modality in PHPT. Studies evaluating the diagnostic accuracy of sPVS for PHPT were electronically searched in the PubMed, EMBASE, Web of Science, and Cochrane Controlled Trials Register databases. Two independent authors reviewed the studies, and revised quality assessment of diagnostic accuracy study tool was used for the quality assessment. Study heterogeneity and pooled estimates were calculated. Two hundred and two unique studies were identified. Of those, 12 studies were included in the meta-analysis. Pooled sensitivity, specificity, and positive likelihood ratio (PLR) of sPVS were 74%, 41%, and 1.55, respectively. The area-under-the-receiver operating characteristic curve was 0.684, indicating an average discriminatory ability of sPVS. On comparison between sPVS and noninvasive imaging modalities, sensitivity, PLR, and positive posttest probability were significantly higher in sPVS compared to noninvasive imaging modalities. Interestingly, super-selective venous sampling had the highest sensitivity, accuracy, and positive posttest probability compared to other parathyroid venous sampling techniques. This is the first meta-analysis to examine the accuracy of sPVS in PHPT. sPVS had higher pooled sensitivity when compared to noninvasive modalities in revision parathyroid surgery. However, the invasiveness of this technique does not favor its routine use for preoperative localization. Super-selective venous sampling was the most accurate among all other parathyroid venous sampling techniques. Laryngoscope, 2018. © 2018 The American Laryngological, Rhinological and Otological Society, Inc.

Diagnostic performance of serological tests for swine brucellosis in the presence of false positive serological reactions.

PubMed

Dieste-Pérez, L; Blasco, J M; de Miguel, M J; Moriyón, I; Muñoz, P M

2015-04-01

Swine brucellosis caused by Brucella suis biovar 2 is an emerging disease in Europe. Currently used diagnostic tests for swine brucellosis detect antibodies to the O-polysaccharide (O-PS) of Brucella smooth lipopolysaccharide (S-LPS) but their specificity is compromised by false-positive serological reactions (FPSRs) when bacteria carrying cross-reacting O-PS infect pigs. FPSRs occur throughout Europe, and the only tool available for a specific B. suis diagnosis is the intradermal test with Brucella protein extracts free of O-PS or S-LPS. Using sera of 162 sows naturally infected by B. suis biovar 2, 406 brucellosis-free sows, and 218 pigs of brucellosis-free farms affected by FPSR, we assessed the diagnostic performance of an indirect ELISA with rough LPS (thus devoid of O-PS) and of gel immunodiffusion, counterimmunoelectrophoresis, latex agglutination and indirect ELISA with O-PS free proteins in comparison with several S-LPS tests (Rose Bengal, complement fixation, gel immunodiffusion and indirect ELISA). When adjusted to 100% specificity, the sensitivity of the rough LPS ELISA was very low (30%), and adoption of other cut-offs resulted in poor specificity/sensitivity ratios. Although their specificity was 100%, the sensitivity of protein tests (ELISA, latex agglutination, counterimmunoelectrophoresis, and gel immunodiffusion) was only moderate (45, 58, 61 and 63%, respectively). Among S-LPS tests, gel immunodiffusion was the only test showing acceptable sensitivity/specificity (68 and 100%, respectively). Despite these shortcomings, and when the purpose is to screen out FPSR at herd level, gel immunodiffusion tests may offer a technically simple and practical alternative to intradermal testing. Copyright © 2015 Elsevier B.V. All rights reserved.

Quality Assurance in the Polio Laboratory. Cell Sensitivity and Cell Authentication Assays.

PubMed

Dunn, Glynis

2016-01-01

The accuracy of poliovirus surveillance is largely dependent on the quality of the cell lines used for virus isolation, which is the foundation of poliovirus diagnostic work. Many cell lines are available for the isolation of enteroviruses, whilst genetically modified L20B cells can be used as a diagnostic tool for the identification of polioviruses. To be confident that cells can consistently isolate the virus of interest, it is necessary to have a quality assurance system in place, which will ensure that the cells in use are not contaminated with other cell lines or microorganisms and that they remain sensitive to the viruses being studied.The sensitivity of cell lines can be assessed by the regular testing of a virus standard of known titer in the cell lines used for virus isolation. The titers obtained are compared to previously obtained titers in the same assay, so that any loss of sensitivity can be detected.However, the detection of cell line cross contamination is more difficult. DNA bar coding is a technique that uses a short DNA sequence from a standardized position in the genome as a molecular diagnostic assay for species-level identification. For almost all groups of higher animals, the cytochrome c oxidase subunit 1 of mitochondrial DNA (CO1) is emerging as the standard barcode region. This region is 648 nucleotide base pairs long in most phylogenetic groups and is flanked by regions of conserved sequences, making it relatively easy to isolate and analyze. DNA barcodes vary among individuals of the same species to a very minor degree (generally less than 1-2 %), and a growing number of studies have shown that the COI sequences of even closely related species differ by several per cent, making it possible to identify different species with high confidence.

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.

Problem Representation, Background Evidence, Analysis, Recommendation: An Oral Case Presentation Tool to Promote Diagnostic Reasoning.

PubMed

Carter, Cristina; Akar-Ghibril, Nicole; Sestokas, Jeff; Dixon, Gabrina; Bradford, Wilhelmina; Ottolini, Mary

2018-03-01

Oral case presentations provide an opportunity for trainees to communicate diagnostic reasoning at the bedside. However, few tools exist to enable faculty to provide effective feedback. We developed a tool to assess diagnostic reasoning and communication during oral case presentations. Published by Elsevier Inc.

Measuring diagnostic and predictive accuracy in disease management: an introduction to receiver operating characteristic (ROC) analysis.

PubMed

Linden, Ariel

2006-04-01

Diagnostic or predictive accuracy concerns are common in all phases of a disease management (DM) programme, and ultimately play an influential role in the assessment of programme effectiveness. Areas, such as the identification of diseased patients, predictive modelling of future health status and costs and risk stratification, are just a few of the domains in which assessment of accuracy is beneficial, if not critical. The most commonly used analytical model for this purpose is the standard 2 x 2 table method in which sensitivity and specificity are calculated. However, there are several limitations to this approach, including the reliance on a single defined criterion or cut-off for determining a true-positive result, use of non-standardized measurement instruments and sensitivity to outcome prevalence. This paper introduces the receiver operator characteristic (ROC) analysis as a more appropriate and useful technique for assessing diagnostic and predictive accuracy in DM. Its advantages include; testing accuracy across the entire range of scores and thereby not requiring a predetermined cut-off point, easily examined visual and statistical comparisons across tests or scores, and independence from outcome prevalence. Therefore the implementation of ROC as an evaluation tool should be strongly considered in the various phases of a DM programme.

Evaluation of outpatients with suspected pulmonary tuberculosis in a high HIV prevalence setting in Ethiopia: clinical, diagnostic and epidemiological characteristics.

PubMed

Bruchfeld, Judith; Aderaye, Getachew; Palme, Ingela Berggren; Bjorvatn, Bjarne; Britton, Sven; Feleke, Yewenhareg; Källenius, Gunilla; Lindquist, Lars

2002-01-01

In a setting with a high prevalence of HIV we studied (i) the prevalence of pulmonary tuberculosis (PTB) and HIV; (ii) clinical and epidemiological characteristics of PTB; and (iii) the usefulness of standard procedures for diagnosing PTB. Of 509 consecutive outpatients evaluated on clinical suspicion of PTB in Addis Ababa, 33.0% were culture-verified as having PTB. PTB patients, non-TB patients and controls were HIV-1-positive in 57.1%, 38.5% and 8.3% of cases, respectively. Predictors for culture-verified PTB were age < 25 y, male gender and the presence of HIV and fever, whereas profound weight loss indicated HIV infection. Diagnosis of PTB based on clinical symptoms, sputum microscopy for acid-fast bacilli and chest radiography was sensitive (86.7%) but unspecific (64.1%). In HIV-positive patients both sensitivity and specificity were significantly lower (p < 0.05). HIV-related pulmonary infections are often misinterpreted as smear-negative PTB. HIV screening is therefore warranted not only in cases of verified TB but also as part of the diagnostic work-up in patients with respiratory symptoms suggestive of PTB. Also, increased awareness of, and improved diagnostic tools for, HIV-related pulmonary infections other than PTB are required, together with algorithms for patients with suspected PTB.

Diagnostic value of prostate-specific antigen in women with polycystic ovary syndrome.

PubMed

Mardanian, Farahnaz; Heidari, Nasrin

2011-08-01

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women. Its presentation is that of irregular menstruation associated with ovulation defects. Because of adverse outcomes such as metabolic and cardiovascular disorders, its diagnosis and treatment is very important. Therefore, the diagnostic value of prostatespecific antigen (PSA) in women with polycystic ovary syndrome was evaluated. A total of 32 women with PCOS and 32 aged matched healthy females were recruited in this case-control study. The subjects were compared by means of metabolic measures and serum PSA level. The correlations between these markers were evaluated. Sensitivity and specificity values and cut off levels of PSA were established for diagnosis of PCOS. Mean PSA, Ferriman Gallwey score (FGS), luteinizing hormone/follicle stimulating hormone ratio (LH/FSH), testosterone, dehydroepiandrosterone sulfate (DHEAS), 17(α) hydroxyprogesterone (17(α) HP) levels were significantly higher in PCOS (P<0.001, respectively). PSA levels greater than 0.07 ng/ml yielded a sensitivity of 91% and specificity of 82%, and was helpful as a diagnostic tool for women with PCOS. Circulating androgens and hirsutism were associated with higher levels of PSA in PCOS women. Our results showed direct correlation between PSA, hirsutism and hyperandrogemsm state. Therefore, it seems logical to use PSA level for detection of hyperandrogemsm state in women.

Recall Tests Are Effective to Detect Mild Cognitive Impairment: A Systematic Review and Meta-analysis of 108 Diagnostic Studies.

PubMed

Tsoi, Kelvin K F; Chan, Joyce Y C; Hirai, Hoyee W; Wong, Adrian; Mok, Vincent C T; Lam, Linda C W; Kwok, Timothy C Y; Wong, Samuel Y S

2017-09-01

Mild cognitive impairment (MCI) is a prevalent symptom associated with the increased risk of dementia. There are many cognitive tests available for detection of MCI, and investigation of the diagnostic performance of the tests is deemed necessary. This study aims to evaluate the diagnostic performance of different cognitive tests used for MCI detection. A list of cognitive tests was identified in previous reviews and from online search engines. Literature searches were performed on each of the cognitive tests in MEDLINE, Embase, and PsycINFO from the earliest available dates of individual databases to December 31, 2016. Google Scholar was used as a supplementary search tool. Studies that were used to assess the diagnostic performance of the cognitive tests were extracted with inclusion and exclusion criteria. Each test's performance was compared with the standard diagnostic criteria. Bivariate random effects models were used to summarize the test performance as a point estimate for sensitivity and specificity, and presented in a summary receiver operating characteristic curve. Reporting quality and risk of bias were evaluated. A total of 108 studies with 23,546 participants were selected to evaluate 9 cognitive tests for MCI detection. Most of the studies used the Mini-Mental State Examination (MMSE) (n = 58) and the Montreal Cognitive Assessment (MoCA) (n = 35). The combined diagnostic performance of the MMSE in MCI detection was 0.71 sensitivity [95% confidence interval (CI): 0.66-0.75] and 0.74 specificity (95% CI: 0.70-0.78), and of the MoCA in MCI detection was 0.83 sensitivity (95% CI: 0.80-0.86) and 0.75 specificity (95% CI: 0.69-0.80). Among the 9 cognitive tests, recall tests showed the best diagnostic performance with 0.89 sensitivity (95% CI: 0.86-0.92) and 0.84 specificity (95% CI, 0.79-0.89). In subgroup analyses, long- or short-delay recall tests have shown better performance than immediate recall tests. Recall tests were shown to be the most effective test in MCI detection, especially for the population with symptoms of memory deterioration. They can be potentially used as the triage screening test for MCI in primary care setting. But when a patient shows cognitive impairments beyond memory deterioration, a more comprehensive test such as the MoCA should be used. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Does the Alpha-defensin Immunoassay or the Lateral Flow Test Have Better Diagnostic Value for Periprosthetic Joint Infection? A Systematic Review.

PubMed

Eriksson, Hannah K; Nordström, Jakob; Gabrysch, Katja; Hailer, Nils P; Lazarinis, Stergios

2018-05-01

Measuring alpha-defensin concentrations in synovial fluid may help to diagnose periprosthetic joint infection (PJI). There are two commercially available methods for measuring alpha-defensin in synovial fluid: the enzyme-linked immunosorbent assay-based Synovasure® alpha-defensin immunoassay, which gives a numeric readout within 24 hours, and the Synovasure lateral flow test, which gives a binary readout within 20 minutes. There is no compilation of the existing literature to support the use of one of these two tests over the other. Does the immunoassay or the lateral flow test have better diagnostic value (sensitivity and specificity) in diagnosing PJI? We followed PRISMA guidelines and identified all studies on alpha-defensin concentration in synovial fluid as a PJI diagnostic marker, indexed to April 14, 2017, in PubMed, JSTOR, Google Scholar, and OVID databases. The search retrieved 1578 records. All prospective and retrospective studies on alpha-defensin as a PJI marker (PJI classified according to the criteria of the Musculoskeletal Infection Society) after THA or TKA were included in the analysis. All studies used only one of the two commercially available test methods, but none of them was comparative. After excluding studies with overlapping patient populations, four studies investigating the alpha-defensin immunoassay and three investigating the lateral flow test remained. Alpha-defensin immunoassay studies included 482 joints and lateral flow test studies included 119. The quality of the trials was assessed according to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. The heterogeneity among studies was evaluated by the I index, indicating that the heterogeneity of the included studies was low. Pooled sensitivity, specificity, positive and negative likelihood ratios, and receiver operating curves were calculated for each method and compared with each other. The alpha-defensin immunoassay had superior overall diagnostic value compared with the lateral flow test (area under the curve, 0.98 versus 0.75) with higher sensitivity (96% [90%-98%] versus 71% [55%-83%], p < 0.001), but no difference in specificity with the numbers available (96% [93%-97%] versus 90% [81%-95%], p = 0.060). Measurement of alpha-defensin in synovial fluid is a valuable complement to existing diagnostic criteria, and the immunoassay test detects PJI more accurately than the lateral flow test. The lateral flow test has lower sensitivity, making it difficult to rule out infection, but its relatively high specificity combined with the advantage of a quick response time can make it useful to rule in infection perioperatively. Level III, diagnostic study.

Sensitivity, specificity, positive and negative predictive values: diagnosing purple mange.

PubMed

Collier, Jill; Huebscher, Roxana

2010-04-01

To shed light on several epidemiological terms for better understanding of diagnostic testing measures by using a mythical condition, "purple mange." Scientific literature related to epidemiology and statistical tests. Nurse practitioners (NPs) use the concepts of sensitivity (SEN), specificity (SPEC), positive predictive value (PPV), and negative predictive value (NPV) daily in primary care and specialty areas. In addition, PPV and NPV vary with the prevalence of a condition. At times, NPs misunderstand the meaning of these terms. In order to develop appropriate treatment plans, an understanding of the concepts of SEN, SPEC, PPV, and NPV is important for interpreting test results. The authors have used this mythical condition purple mange as a teaching tool for NP students.

SEM analysis of ionizing radiation effects in linear integrated circuits. [Scanning Electron Microscope

NASA Technical Reports Server (NTRS)

Stanley, A. G.; Gauthier, M. K.

1977-01-01

A successful diagnostic technique was developed using a scanning electron microscope (SEM) as a precision tool to determine ionization effects in integrated circuits. Previous SEM methods radiated the entire semiconductor chip or major areas. The large area exposure methods do not reveal the exact components which are sensitive to radiation. To locate these sensitive components a new method was developed, which consisted in successively irradiating selected components on the device chip with equal doses of electrons /10 to the 6th rad (Si)/, while the whole device was subjected to representative bias conditions. A suitable device parameter was measured in situ after each successive irradiation with the beam off.

A dielectrophoretic method of discrimination between normal oral epithelium, and oral and oropharyngeal cancer in a clinical setting.

PubMed

Graham, K A; Mulhall, H J; Labeed, F H; Lewis, M P; Hoettges, K F; Kalavrezos, N; McCaul, J; Liew, C; Porter, S; Fedele, S; Hughes, M P

2015-08-07

Despite the accessibility of the oral cavity to clinical examination, delays in diagnosis of oral and oropharyngeal carcinoma (OOPC) are observed in a large majority of patients, with negative impact on prognosis. Diagnostic aids might help detection and improve early diagnosis, but there remains little robust evidence supporting the use of any particular diagnostic technology at the moment. The aim of the present feasibility first-in-human study was to evaluate the preliminary diagnostic validity of a novel technology platform based on dielectrophoresis (DEP). DEP does not require labeling with antibodies or stains and it is an ideal tool for rapid analysis of cell properties. Cells from OOPC/dysplasia tissue and healthy oral mucosa were collected from 57 study participants via minimally-invasive brush biopsies and tested with a prototype DEP platform using median membrane midpoint frequency as main analysis parameter. Results indicate that the current DEP platform can discriminate between brush biopsy samples from cancerous and healthy oral tissue with a diagnostic sensitivity of 81.6% and a specificity of 81.0%. The present ex vivo results support the potential application of DEP testing for identification of OOPC. This result indicates that DEP has the potential to be developed into a low-cost, rapid platform as an assistive tool for the early identification of oral cancer in primary care; given the rapid, minimally-invasive and non-expensive nature of the test, dielectric characterization represents a promising platform for cost-effective early cancer detection.

Diagnostic value of soluble triggering receptor expressed on myeloid cells in paediatric sepsis: a systematic review.

PubMed

Pontrelli, Giuseppe; De Crescenzo, Franco; Buzzetti, Roberto; Calò Carducci, Francesca; Jenkner, Alessandro; Amodio, Donato; De Luca, Maia; Chiurchiù, Sara; Davies, Elin Haf; Simonetti, Alessandra; Ferretti, Elena; Della Corte, Martina; Gramatica, Luca; Livadiotti, Susanna; Rossi, Paolo

2016-04-27

Differential diagnosis between sepsis and non-infectious inflammatory disorders demands improved biomarkers. Soluble Triggering Receptor Expression on Myeloid cells (sTREM-1) is an activating receptor whose role has been studied throughout the last decade. We performed a systematic review to evaluate the accuracy of plasma sTREM-1 levels in the diagnosis of sepsis in children with Systemic Inflammatory Response Syndrome (SIRS). A literature search of PubMed, Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and ISI Web of Knowledge databases was performed using specific search terms. Studies were included if they assessed the diagnostic accuracy of plasma sTREM-1 for sepsis in paediatric patients with SIRS. Data on sensitivity, specificity, positive predictive value, negative predictive value, area under receiver operating characteristic curve were extracted. The methodological quality of each study was assessed using a checklist based on the Quality Assessment Tool for Diagnostic Accuracy Studies. Nine studies comprising 961 patients were included, four of which were in newborns, three in children and two in children with febrile neutropenia. Some data from single studies support a role of sTREM-1 as a diagnostic tool in pediatric sepsis, but cannot be considered conclusive, because a quantitative synthesis was not possible, due to heterogeneity in studies design. This systematic review suggests that available data are insufficient to support a role for sTREM in the diagnosis and follow-up of paediatric sepsis.

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.

Methylene Blue as a Diagnostic Aid in the Early Detection of Potentially Malignant and Malignant Lesions of Oral Mucosa.

PubMed

Lejoy, Abraham; Arpita, Rai; Krishna, Burde; Venkatesh, Naikmasur

2016-05-01

In vivo stains are the prompt resources, which have emerged in recent years to aid as clinical diagnostic tools in detecting early potentially malignant and malignant lesions. Toluidine blue, by its property of retaining in the increased DNA and RNA cellular activity areas, aids in delineating the suspicious areas. However, it is hazardous if swallowed, and has been shown to have toxicity to fibroblasts. Methylene blue has a similar chemical structure and exhibits similar physicochemical properties as toluidine blue. It is less toxic to the human body and has recently been proposed for screening some gastrointestinal or prostate tumors. The application of this material in detecting oral lesions has so far not been addressed. The objective of this study was to evaluate the sensitivity and reliability of in vivo staining with methylene blue as a diagnostic adjunct in screening for oral malignant or potentially malignant lesions. The present study involved the examination of 75 patients suspected of having oral malignant or potentially malignant lesions by methylene blue staining. The results of methylene blue uptake were compared with a simultaneous biopsy of these lesions. The overall sensitivity was 95% (100% for malignancy and 92% for potentially malignant lesions) and specificity was 70%. The positive predictive value was 91% and negative predictive value of 80% was observed in the study. We consider that methylene blue staining is a useful diagnostic adjunct in a large, community-based oral cancer screening program for high-risk individuals.

Genome-wide DNA methylation measurements in prostate tissues uncovers novel prostate cancer diagnostic biomarkers and transcription factor binding patterns.

PubMed

Kirby, Marie K; Ramaker, Ryne C; Roberts, Brian S; Lasseigne, Brittany N; Gunther, David S; Burwell, Todd C; Davis, Nicholas S; Gulzar, Zulfiqar G; Absher, Devin M; Cooper, Sara J; Brooks, James D; Myers, Richard M

2017-04-17

Current diagnostic tools for prostate cancer lack specificity and sensitivity for detecting very early lesions. DNA methylation is a stable genomic modification that is detectable in peripheral patient fluids such as urine and blood plasma that could serve as a non-invasive diagnostic biomarker for prostate cancer. We measured genome-wide DNA methylation patterns in 73 clinically annotated fresh-frozen prostate cancers and 63 benign-adjacent prostate tissues using the Illumina Infinium HumanMethylation450 BeadChip array. We overlaid the most significantly differentially methylated sites in the genome with transcription factor binding sites measured by the Encyclopedia of DNA Elements consortium. We used logistic regression and receiver operating characteristic curves to assess the performance of candidate diagnostic models. We identified methylation patterns that have a high predictive power for distinguishing malignant prostate tissue from benign-adjacent prostate tissue, and these methylation signatures were validated using data from The Cancer Genome Atlas Project. Furthermore, by overlaying ENCODE transcription factor binding data, we observed an enrichment of enhancer of zeste homolog 2 binding in gene regulatory regions with higher DNA methylation in malignant prostate tissues. DNA methylation patterns are greatly altered in prostate cancer tissue in comparison to benign-adjacent tissue. We have discovered patterns of DNA methylation marks that can distinguish prostate cancers with high specificity and sensitivity in multiple patient tissue cohorts, and we have identified transcription factors binding in these differentially methylated regions that may play important roles in prostate cancer development.

Stationary intraoral tomosynthesis for dental imaging

NASA Astrophysics Data System (ADS)

Inscoe, Christina R.; Wu, Gongting; Soulioti, Danai E.; Platin, Enrique; Mol, Andre; Gaalaas, Laurence R.; Anderson, Michael R.; Tucker, Andrew W.; Boyce, Sarah; Shan, Jing; Gonzales, Brian; Lu, Jianping; Zhou, Otto

2017-03-01

Despite recent advances in dental radiography, the diagnostic accuracies for some of the most common dental diseases have not improved significantly, and in some cases remain low. Intraoral x-ray is the most commonly used x-ray diagnostic tool in dental clinics. It however suffers from the typical limitations of a 2D imaging modality including structure overlap. Cone-beam computed tomography (CBCT) uses high radiation dose and suffers from image artifacts and relatively low resolution. The purpose of this study is to investigate the feasibility of developing a stationary intraoral tomosynthesis (s-IOT) using spatially distributed carbon nanotube (CNT) x-ray array technology, and to evaluate its diagnostic accuracy compared to conventional 2D intraoral x-ray. A bench-top s-IOT device was constructed using a linear CNT based X-ray source array and a digital intraoral detector. Image reconstruction was performed using an iterative reconstruction algorithm. Studies were performed to optimize the imaging configuration. For evaluation of s-IOT's diagnostic accuracy, images of a dental quality assurance phantom, and extracted human tooth specimens were acquired. Results show s-IOT increases the diagnostic sensitivity for caries compared to intraoral x-ray at a comparable dose level.

Molecular Classifiers for Acute Kidney Transplant Rejection in Peripheral Blood by Whole Genome Gene Expression Profiling

PubMed Central

Kurian, S. M.; Williams, A. N.; Gelbart, T.; Campbell, D.; Mondala, T. S.; Head, S. R.; Horvath, S.; Gaber, L.; Thompson, R.; Whisenant, T.; Lin, W.; Langfelder, P.; Robison, E. H.; Schaffer, R. L.; Fisher, J. S.; Friedewald, J.; Flechner, S. M.; Chan, L. K.; Wiseman, A. C.; Shidban, H.; Mendez, R.; Heilman, R.; Abecassis, M. M.; Marsh, C. L.; Salomon, D. R.

2015-01-01

There are no minimally invasive diagnostic metrics for acute kidney transplant rejection (AR), especially in the setting of the common confounding diagnosis, acute dysfunction with no rejection (ADNR). Thus, though kidney transplant biopsies remain the gold standard, they are invasive, have substantial risks, sampling error issues and significant costs and are not suitable for serial monitoring. Global gene expression profiles of 148 peripheral blood samples from transplant patients with excellent function and normal histology (TX; n = 46), AR (n = 63) and ADNR (n = 39), from two independent cohorts were analyzed with DNA microarrays. We applied a new normalization tool, frozen robust multi-array analysis, particularly suitable for clinical diagnostics, multiple prediction tools to discover, refine and validate robust molecular classifiers and we tested a novel one-by-one analysis strategy to model the real clinical application of this test. Multiple three-way classifier tools identified 200 highest value probesets with sensitivity, specificity, positive predictive value, negative predictive value and area under the curve for the validation cohort ranging from 82% to 100%, 76% to 95%, 76% to 95%, 79% to 100%, 84% to 100% and 0.817 to 0.968, respectively. We conclude that peripheral blood gene expression profiling can be used as a minimally invasive tool to accurately reveal TX, AR and ADNR in the setting of acute kidney transplant dysfunction. PMID:24725967

Identification of a new diagnostic antigen for glanders using immunoproteome analysis.

PubMed

Dohre, Sudhir K; Kamthan, Aayushi; Singh, Sandeep; Alam, Syed Imteyaz; Kumar, Subodh

2017-08-01

Glanders is a disease of horses, donkeys and mules. The causative agent Burkholderia mallei, is a biorisk group 3 pathogen and is also a biothreat agent. Simple and rapid diagnostic tool is essential for control of glanders. Using a proteomic approach and immunoblotting with equine sera, we identified 12 protein antigens that may have diagnostic potential. Various immunoreactive proteins e.g. GroEL, translation elongation factor Tu, elongation factor Ts, arginine deiminase, malate dehydrogenase, DNA directed RNA polymerase subunit alpha were identified on 2-dimentional immunoblots. One of these proteins, GroEL, was cloned and expressed in E. coli and purified using Ni-NTA affinity chromatography. The recombinant GroEL protein was evaluated in ELISA format on a panel of glanders positive (n=49) and negative (n=79) equine serum samples to determine its diagnostic potential. The developed ELISA had a sensitivity and specificity of 96 and 98.7% respectively. The results of this study highlight the potential of GroEL in serodiagnosis of glanders. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Prevalence of PCR detectable malaria infection among febrile patients with a negative Plasmodium falciparum specific rapid diagnostic test in Zanzibar.

PubMed

Baltzell, Kimberly A; Shakely, Deler; Hsiang, Michelle; Kemere, Jordan; Ali, Abdullah Suleiman; Björkman, Anders; Mårtensson, Andreas; Omar, Rahila; Elfving, Kristina; Msellem, Mwinyi; Aydin-Schmidt, Berit; Rosenthal, Philip J; Greenhouse, Bryan

2013-02-01

We screened for malaria in 594 blood samples from febrile patients who tested negative by a Plasmodium falciparum-specific histidine-rich protein-2-based rapid diagnostic test at 12 health facilities in Zanzibar districts North A and Micheweni, from May to August 2010. Screening was with microscopy, polymerase chain reaction (PCR) targeting the cytochrome b gene (cytbPCR) of the four major human malaria species, and quantitative PCR (qPCR). The prevalence of cytbPCR-detectable malaria infection was 2% (12 of 594), including 8 P. falciparum, 3 Plasmodium malariae, and 1 Plasmodium vivax infections. Microscopy identified 4 of 8 P. falciparum infections. Parasite density as estimated by microscopy or qPCR was > 4,000 parasites/μL in 5 of 8 cytbPCR-detectable P. falciparum infections. The infections that were missed by the rapid diagnostic test represent a particular challenge in malaria elimination settings and highlight the need for more sensitive point-of-care diagnostic tools to improve case detection of all human malaria species in febrile patients.

Detection of Catheter-Related Bloodstream Infections by the Differential-Time-to-Positivity Method and Gram Stain-Acridine Orange Leukocyte Cytospin Test in Neutropenic Patients after Hematopoietic Stem Cell Transplantation

PubMed Central

Krause, R.; Auner, H. W.; Gorkiewicz, G.; Wölfler, A.; Daxboeck, F.; Linkesch, W.; Krejs, G. J.; Wenisch, C.; Reisinger, E. C.

2004-01-01

For febrile neutropenic patients who received hematopoietic stem cell transplantation, the Gram stain-acridine orange leukocyte cytospin (AOLC) test and the differential-time-to-positivity method (DTP) were performed. As a diagnostic tool for catheter-related bloodstream infections in these patients, the Gram stain-AOLC test has a lower sensitivity than does the DTP method but acceptable positive and negative predictive values. PMID:15472355

Diagnostic Molecular Microbiology: A 2018 Snapshot.

PubMed

Fairfax, Marilynn Ransom; Bluth, Martin H; Salimnia, Hossein

2018-06-01

Molecular biological techniques have evolved expeditiously and in turn have been applied to the detection of infectious disease. Maturation of these technologies and their coupling with related technological advancement in fluorescence, electronics, digitization, nanodynamics, and sensors among others have afforded clinical medicine additional tools toward expedient identification of infectious organisms at concentrations and sensitivities previously unattainable. These advancements have been adapted in select settings toward addressing clinical demands for more timely and effective patient management. Copyright © 2018 Elsevier Inc. All rights reserved.

Voltage and Current Measurements in HIFX Diodes

DTIC Science & Technology

1977-08-01

Laboratories High- Intensity Flash X Ray Pacility. Sensitivities of these monitors have been measured to an accuracy of 10 percent or better by improved...importance of voltage (V) and current (1) monitors as a diagnostic tool for pulsed-electron beam machines such as High-Intensity Flash X Ray (HIFX) is well...15.4 2.7 109515. .2 7. - 3. 172.6 6.0 2.30 36. 4T. H. Martin, K. R. Prestwicht and D. L. Johnson, Summary of th e Hermes Flash X -Ray Program, Sandia

[Nuclear medicine diagnosis of pheochromocytoma].

PubMed

Farahati, J; Reiners, C

1997-01-01

The synthesis of radioiodinated meta-iodobenzylguanidine (MIBG), a physiologic norepinephrine analog, was first accomplished by a group from the University of Michigan. Since the first report of the detection of pheochromocytoma with MIBG in humans, there have been several studies about the role of this agent in the diagnosis of pheochromocytoma and neuroblastoma. With a sensitivity of about 90% and a specificity of nearly 100% MIBG has been shown to be a reliable diagnostic tool for the detection and follow-up of pheochromocytoma.

Diagnostic value of unenhanced postmortem computed tomography in the detection of traumatic abdominal injuries.

PubMed

Carballeira Álvarez, A; Mancini, J; Tuchtan-Torrents, L; Gach, P; Bartoli, C; Desfeux, J; Piercecchi, M D; Gorincour, G

2018-02-20

To determine the diagnostic capabilities of unenhanced postmortem computed tomography (UPMCT) in detecting traumatic abdominal injuries. Cases of traumatic death with both UPMCT and classical autopsy were collected retrospectively from our institution "virtopsy" database in a period of 5 years. Cadavers with gunshot injuries were excluded. Sensitivity, specificity, accuracy, negative (NPV) and positive (PPV) predictive values of PMCT globally and for hemoperitoneum, liver, spleen, pancreas and kidney injuries individually were estimated using the autopsy report as gold standard. Seventy-one cadavers were included. UPMCT had a sensitivity of 80% and a specificity 94%, with an accuracy of 83%, a PPV of 98% and a NPV of 59% for the diagnosis of traumatic abdominal injuries. The highest sensitivity was obtained for the detection of hepatic injuries (71%) and the lowest for pancreatic injuries (12%). UPMCT had a specificity of 100% for the detection of hemoperitoneum. A NPV of 98% was found for the detection of perihepatic hematomas. The low sensitivity and low NPV do not support the use of UPMCT as an alternative to conventional autopsy to diagnose and/or rule out traumatic abdominal injuries. Nevertheless, UPMCT remains a helpful tool as it helps detect hemoperitoneum and virtually exclude presence of perihepatic hematomas. Copyright © 2018 Société française de radiologie. Published by Elsevier Masson SAS. All rights reserved.

Species-specific diagnostic assays for Bonamia ostreae and B. exitiosa in European flat oyster Ostrea edulis: conventional, real-time and multiplex PCR.

PubMed

Ramilo, Andrea; Navas, J Ignacio; Villalba, Antonio; Abollo, Elvira

2013-05-27

Bonamia ostreae and B. exitiosa have caused mass mortalities of various oyster species around the world and co-occur in some European areas. The World Organisation for Animal Health (OIE) has included infections with both species in the list of notifiable diseases. However, official methods for species-specific diagnosis of either parasite have certain limitations. In this study, new species-specific conventional PCR (cPCR) and real-time PCR techniques were developed to diagnose each parasite species. Moreover, a multiplex PCR method was designed to detect both parasites in a single assay. The analytical sensitivity and specificity of each new method were evaluated. These new procedures were compared with 2 OIE-recommended methods, viz. standard histology and PCR-RFLP. The new procedures showed higher sensitivity than the OIE recommended ones for the diagnosis of both species. The sensitivity of tests with the new primers was higher using oyster gills and gonad tissue, rather than gills alone. The lack of a 'gold standard' prevented accurate estimation of sensitivity and specificity of the new methods. The implementation of statistical tools (maximum likelihood method) for the comparison of the diagnostic tests showed the possibility of false positives with the new procedures, although the absence of a gold standard precluded certainty. Nevertheless, all procedures showed negative results when used for the analysis of oysters from a Bonamia-free area.

Bedside diagnosis of dysphagia: a systematic review.

PubMed

O'Horo, John C; Rogus-Pulia, Nicole; Garcia-Arguello, Lisbeth; Robbins, JoAnne; Safdar, Nasia

2015-04-01

Dysphagia is associated with aspiration, pneumonia, and malnutrition, but remains challenging to identify at the bedside. A variety of exam protocols and maneuvers are commonly used, but the efficacy of these maneuvers is highly variable. We conducted a comprehensive search of 7 databases, including MEDLINE, Embase, and Scopus, from each database's earliest inception through June 9, 2014. Studies reporting diagnostic performance of a bedside examination maneuver compared to a reference gold standard (videofluoroscopic swallow study or flexible endoscopic evaluation of swallowing with sensory testing) were included for analysis. From each study, data were abstracted based on the type of diagnostic method and reference standard study population and inclusion/exclusion characteristics, design, and prediction of aspiration. The search strategy identified 38 articles meeting inclusion criteria. Overall, most bedside examinations lacked sufficient sensitivity to be used for screening purposes across all patient populations examined. Individual studies found dysphonia assessments, abnormal pharyngeal sensation assessments, dual axis accelerometry, and 1 description of water swallow testing to be sensitive tools, but none were reported as consistently sensitive. A preponderance of identified studies was in poststroke adults, limiting the generalizability of results. No bedside screening protocol has been shown to provide adequate predictive value for presence of aspiration. Several individual exam maneuvers demonstrated reasonable sensitivity, but reproducibility and consistency of these protocols was not established. More research is needed to design an optimal protocol for dysphagia detection. © 2015 Society of Hospital Medicine.

Diagnostic accuracy of HbA1c in diabetes between Eastern and Western.

PubMed

Yan, Shuang; Liu, Siying; Zhao, Yashuang; Zhang, Wencui; Sun, Xiaohui; Li, Jianing; Jiang, Fuli; Ju, Jiaming; Lang, Ning; Zhang, Yingqi; Zhou, Weiyu; Li, Qiang

2013-07-01

In 2010, the American Diabetes Association recommended the use of HbA1c as a diagnostic criterion for diabetes. However, HbA1c is not an accepted diagnostic tool for diabetes in Eastern Asia, because genetic differences compromise the standardization of the diagnostic cut-off point. This study evaluated differences in the use of HbA1c for diagnosing diabetes in Eastern and Western populations and investigated whether HbA1c cut-off point of ≥ 6.5% is diagnostic of diabetes in patients from Eastern Asia. Literature was obtained from MEDLINE, EMBASE and Cochrane databases. The pooled sensitivity and specificity of each HbA1c cut-off point were extracted and compared between Western and Eastern populations. Differences in the cut-off point for diagnosing diabetes in each region were compared by examining differences in the area under summary receiver operating characteristic (SROC) curves. Twelve publications from Eastern countries (n = 59,735) and 13 from Western countries (n = 22,954) were included in the analysis. Areas under SROC curves in the Eastern and Western groups were 0.9331 and 0.9120, respectively (P = 0.98). The cut-off point of the highest Youden index was 6.0%. At the HbA1c cut-off point of 6.5%, the pooled sensitivity and specificity were 58.7% and 98.4% for Eastern countries and 65.5% and 98.1% for Western countries, respectively. HbA1c exhibits the same diagnostic value for diabetes in Eastern and Western populations. In both populations, HbA1c levels > 6.0% identify the population at high risk of diabetes, and HbA1c > 6.5% is diagnostic of clinically established diabetes. © 2013 Stichting European Society for Clinical Investigation Journal Foundation. Published by John Wiley & Sons Ltd.

CT-guided transthoracic core needle biopsy for small pulmonary lesions: diagnostic performance and adequacy for molecular testing.

PubMed

Tian, Panwen; Wang, Ye; Li, Lei; Zhou, Yongzhao; Luo, Wenxin; Li, Weimin

2017-02-01

Computed tomography (CT)-guided transthoracic needle biopsy is a well-established, minimally invasive diagnostic tool for pulmonary lesions. Few large studies have been conducted on the diagnostic performance and adequacy for molecular testing of transthoracic core needle biopsy (TCNB) for small pulmonary lesions. This study included CT-guided TCNB with 18-gauge cutting needles in 560 consecutive patients with small (≤3 cm) pulmonary lesions from January 2012 to January 2015. There were 323 males and 237 females, aged 51.8±12.7 years. The size of the pulmonary lesions was 1.8±0.6 cm. The sensitivity, specificity, accuracy and complications of the biopsies were investigated. The risk factors of diagnostic failure were assessed using univariate and multivariate analyses. The sample's adequacy for molecular testing of non-small cell lung cancer (NSCLC) was analyzed. The overall sensitivity, specificity, and accuracy for diagnosis of malignancy were 92.0% (311/338), 98.6% (219/222), and 94.6% (530/560), respectively. The incidence of bleeding complications was 22.9% (128/560), and the incidence of pneumothorax was 10.4% (58/560). Logistic multivariate regression analysis showed that the independent risk factors for diagnostic failure were a lesion size ≤1 cm [odds ratio (OR), 3.95; P=0.007], lower lobe lesions (OR, 2.83; P=0.001), and pneumothorax (OR, 1.98; P=0.004). Genetic analysis was successfully performed on 95.45% (168/176) of specimens diagnosed as NSCLC. At least 96.8% of samples with two or more passes from a lesion were sufficient for molecular testing. The diagnostic yield of small pulmonary lesions by CT-guided TCNB is high, and the procedure is relatively safe. A lesion size ≤1 cm, lower lobe lesions, and pneumothorax are independent risk factors for biopsy diagnostic failure. TCNB specimens could provide adequate tissues for molecular testing.

Clinical detection of deletion structural variants in whole-genome sequences

PubMed Central

Noll, Aaron C; Miller, Neil A; Smith, Laurie D; Yoo, Byunggil; Fiedler, Stephanie; Cooley, Linda D; Willig, Laurel K; Petrikin, Josh E; Cakici, Julie; Lesko, John; Newton, Angela; Detherage, Kali; Thiffault, Isabelle; Saunders, Carol J; Farrow, Emily G; Kingsmore, Stephen F

2016-01-01

Optimal management of acutely ill infants with monogenetic diseases requires rapid identification of causative haplotypes. Whole-genome sequencing (WGS) has been shown to identify pathogenic nucleotide variants in such infants. Deletion structural variants (DSVs, >50 nt) are implicated in many genetic diseases, and tools have been designed to identify DSVs using short-read WGS. Optimisation and integration of these tools into a WGS pipeline could improve diagnostic sensitivity and specificity of WGS. In addition, it may improve turnaround time when compared with current CNV assays, enhancing utility in acute settings. Here we describe DSV detection methods for use in WGS for rapid diagnosis in acutely ill infants: SKALD (Screening Konsensus and Annotation of Large Deletions) combines calls from two tools (Breakdancer and GenomeStrip) with calibrated filters and clinical interpretation rules. In four WGS runs, the average analytic precision (positive predictive value) of SKALD was 78%, and recall (sensitivity) was 27%, when compared with validated reference DSV calls. When retrospectively applied to a cohort of 36 families with acutely ill infants SKALD identified causative DSVs in two. The first was heterozygous deletion of exons 1–3 of MMP21 in trans with a heterozygous frame-shift deletion in two siblings with transposition of the great arteries and heterotaxy. In a newborn female with dysmorphic features, ventricular septal defect and persistent pulmonary hypertension, SKALD identified the breakpoints of a heterozygous, de novo 1p36.32p36.13 deletion. In summary, consensus DSV calling, implemented in an 8-h computational pipeline with parameterised filtering, has the potential to increase the diagnostic yield of WGS in acutely ill neonates and discover novel disease genes. PMID:29263817

Paradigm for diagnosing mycobacterial disease: direct detection and differentiation of Mycobacterium tuberculosis complex and non-tuberculous mycobacteria in clinical specimens using multiplex real-time PCR.

PubMed

Kim, Jeong-Uk; Ryu, Dae-Shick; Cha, Choong-Hwan; Park, Seon-Hee

2018-03-20

Mycobacterium tuberculosis and non-tuberculous mycobacteria (NTM) are clinically different, and the rapid detection and differentiation of M. tuberculosis complex (MTBC) and NTM is crucial for patient management and infection control. Given the slow growth of most pathogenic mycobacteria, nucleic acid amplification assays are excellent tools for direct identification of mycobacteria in clinical specimens. Recently, a multiplex real-time PCR assay was developed that can directly detect 20 mycobacterial species in clinical specimens. Here, we evaluated the diagnostic performance of the assay for diagnosing mycobacterial disease under routine laboratory conditions. A total of 3334 specimens collected from 1437 patients suspected of tuberculosis infection were subjected to acid-fast bacilli staining, conventional culture and the multiplex real-time PCR assay. To evaluate the sensitivity and specificity of the assay, the overall diagnosis of tuberculosis was defined by positive culture plus medical history, and the 2007 American Thoracic Society and Infectious Disease Society of America diagnostic criteria for NTM disease were applied. The sensitivity, specificity, positive predictive value and negative predictive value were 87.5%, 99.6%, 96.1% and 98.5%, respectively, for the detection of MTBC isolates and 53.3%, 99.9%, 95.2%, and 98.9%, respectively, for detecting NTM isolates. Thus, the assay can correctly differentiate between MTBC and NTM isolates in clinical specimens and would be a useful tool for the rapid differentiation of tuberculosis and NTM disease, despite its limited sensitivity for the diagnosis of NTM disease. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Clinical application of the basic definition of malnutrition proposed by the European Society for Clinical Nutrition and Metabolism (ESPEN): Comparison with classical tools in geriatric care.

PubMed

Sánchez-Rodríguez, Dolores; Annweiler, Cédric; Ronquillo-Moreno, Natalia; Tortosa-Rodríguez, Andrea; Guillén-Solà, Anna; Vázquez-Ibar, Olga; Escalada, Ferran; Muniesa, Josep M; Marco, Ester

Malnutrition is a prevalent condition related to adverse outcomes in older people. Our aim was to compare the diagnostic capacity of the malnutrition criteria of the European Society of Parenteral and Enteral Nutrition (ESPEN) with other classical diagnostic tools. Cohort study of 102 consecutive in-patients ≥70 years admitted for postacute rehabilitation. Patients were considered malnourished if their Mini-Nutritional Assessment-Short Form (MNA-SF) score was ≤11 and serum albumin <3 mg/dL or MNA-SF ≤ 11, serum albumin <3 mg/dL, and usual clinical signs and symptoms of malnutrition. Sensitivity, specificity, positive and negative predictive values, accuracy likelihood ratios, and kappa values were calculated for both methods: and compared with ESPEN consensus. Of 102 eligible in-patients, 88 fulfilled inclusion criteria and were identified as "at risk" by MNA-SF. Malnutrition diagnosis was confirmed in 11.6% and 10.5% of the patients using classical methods,whereas 19.3% were malnourished according to the ESPEN criteria. Combined with low albumin levels, the diagnosis showed 57.9% sensitivity, 64.5% specificity, 85.9% negative predictive value,0.63 accuracy (fair validity, low range), and kappa index of 0.163 (poor ESPEN agreement). The combination of MNA-SF, low albumin, and clinical malnutrition showed 52.6% sensitivity, 88.3% specificity, 88.3%negative predictive value, and 0.82 accuracy (fair validity, low range), and kappa index of 0.43 (fair ESPEN agreement). Malnutrition was almost twice as prevalent when diagnosed by the ESPEN consensus, compared to classical assessment methods: Classical methods: showed fair validity and poor agreement with the ESPEN consensus in assessing malnutrition in geriatric postacute care. Copyright © 2018 Elsevier B.V. All rights reserved.

Chip-Based Sensors for Disease Diagnosis

NASA Astrophysics Data System (ADS)

Fang, Zhichao

Nucleic acid analysis is one of the most important disease diagnostic approaches in medical practice, and has been commonly used in cancer biomarker detection, bacterial speciation and many other fields in laboratory. Currently, the application of powerful research methods for genetic analysis, including the polymerase chain reaction (PCR), DNA sequencing, and gene expression profiling using fluorescence microarrays, are not widely used in hospitals and extended-care units due to high-cost, long detection times, and extensive sample preparation. Bioassays, especially chip-based electrochemical sensors, may be suitable for the next generation of rapid, sensitive, and multiplexed detection tools. Herein, we report three different microelectrode platforms with capabilities enabled by nano- and microtechnology: nanoelectrode ensembles (NEEs), nanostructured microelectrodes (NMEs), and hierarchical nanostructured microelectrodes (HNMEs), all of which are able to directly detect unpurified RNA in clinical samples without enzymatic amplification. Biomarkers that are cancer and infectious disease relevant to clinical medicine were chosen to be the targets. Markers were successfully detected with clinically-relevant sensitivity. Using peptide nucleic acids (PNAs) as probes and an electrocatalytic reporter system, NEEs were able to detect prostate cancer-related gene fusions in tumor tissue samples with 100 ng of RNA. The development of NMEs improved the sensitivity of the assay further to 10 aM of DNA target, and multiplexed detection of RNA sequences of different prostate cancer-related gene fusion types was achieved on the chip-based NMEs platform. An HNMEs chip integrated with a bacterial lysis device was able to detect as few as 25 cfu bacteria in 30 minutes and monitor the detection in real time. Bacterial detection could also be performed in neat urine samples. The development of these versatile clinical diagnostic tools could be extended to the detection of various cancers, genetic, and infectious diseases.

Microcolony culture techniques for tuberculosis diagnosis: a systematic review.

PubMed

Leung, E; Minion, J; Benedetti, A; Pai, M; Menzies, D

2012-01-01

There is considerable demand for quicker and more affordable yet accurate diagnostic tools for tuberculosis (TB). The microscopic observation drug susceptibility (MODS) assay and the thin-layer agar (TLA) assay are inexpensive, rapid microcolony-based culture methods. A systematic review and meta-analysis was performed to assess the accuracy and other test characteristics of MODS and TLA compared to a reference standard of traditional solid or liquid culture. Pooled estimates of sensitivity and specificity and their 95% confidence intervals were estimated with an exact binomial likelihood random effects meta-analysis. A total of 21 eligible studies were identified, 12 that evaluated MODS, seven that evaluated TLA and two that evaluated both. The overall pooled sensitivity and specificity of MODS were respectively 92% (95%CI 87-97) and 96% (90-100), and for TLA they were respectively 87% (95%CI 79-94) and 98% (95%CI 94-100), although there was considerable heterogeneity of results. When the studies were restricted to those assessing accuracy of MODS in sputum samples only, the sensitivity was 96% (95%CI 94-98) and the specificity 96% (95%CI 89-100). The mean intervals from reception of specimens to results were 9.2 days with MODS and 11.5 days with TLA; contamination rates averaged 6.6% with MODS and 12.3% with TLA; materials and supplies costs averaged US$1.48 for MODS and US$2.42 for TLA. MODS and TLA appear to be accurate and rapid yet inexpensive diagnostic tools for active TB. However, this review did not find sufficient evidence on the feasibility and costs of implementation of these tests, nor on the impact of these tests on patient outcomes.

A multiplex PCR assay for the rapid and sensitive detection of methicillin-resistant Staphylococcus aureus and simultaneous discrimination of Staphylococcus aureus from coagulase-negative staphylococci.

PubMed

Xu, Benjin; Liu, Ling; Liu, Li; Li, Xinping; Li, Xiaofang; Wang, Xin

2012-11-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a global health concern, which had been detected in food and food production animals. Conventional testing for detection of MRSA takes 3 to 5 d to yield complete information of the organism and its antibiotic sensitivity pattern. So, a rapid method is needed to diagnose and treat the MRSA infections. The present study focused on the development of a multiplex PCR assay for the rapid and sensitive detection of MRSA. The assay simultaneously detected 4 genes, namely, 16S rRNA of the Staphylococcus genus, femA of S. aureus, mecA that encodes methicillin resistance, and one internal control. It was rapid and yielded results within 4 h. The analytical sensitivity and specificity of the multiplex PCR assay was evaluated by comparing it with the conventional method. The analytical sensitivity of the multiplex PCR assay at the DNA level was 10 ng DNA. The analytical specificity was evaluated with 10 reference staphylococci strains and was 100%. The diagnostic evaluation of MRSA was carried out using 360 foodborne staphylococci isolates, and showed 99.1% of specificity, 96.4% of sensitivity, 97.5% of positive predictive value, and 97.3% of negative predictive value compared to the conventional method. The inclusion of an internal control in the multiplex PCR assay is important to exclude false-negative cases. This test can be used as an effective diagnostic and surveillance tool to investigate the spread and emergence of MRSA. © 2012 Institute of Food Technologists®

Sensitivity and specificity of the American College of Rheumatology 1987 criteria for the diagnosis of rheumatoid arthritis according to disease duration: a systematic literature review and meta-analysis.

PubMed

Banal, F; Dougados, M; Combescure, C; Gossec, L

2009-07-01

To evaluate the ability of the widely used ACR set of criteria (both list and tree format) to diagnose RA compared with expert opinion according to disease duration. A systematic literature review was conducted in PubMed and Embase databases. All articles reporting the prevalence of RA according to ACR criteria and expert opinion in cohorts of early (<1 year duration) or established (>1 year) arthritis were analysed to calculate the sensitivity and specificity of ACR 1987 criteria against the "gold standard" (expert opinion). A meta-analysis using a summary receiver operating characteristic (SROC) curve was performed and pooled sensitivity and specificity were calculated with confidence intervals. Of 138 publications initially identified, 19 were analysable (total 7438 patients, 3883 RA). In early arthritis, pooled sensitivity and specificity of the ACR set of criteria were 77% (68% to 84%) and 77% (68% to 84%) in the list format versus 80% (72% to 88%) and 33% (24% to 43%) in the tree format. In established arthritis, sensitivity and specificity were respectively 79% (71% to 85%) and 90% (84% to 94%) versus 80% (71% to 85%) and 93% (86% to 97%). The SROC meta-analysis confirmed the statistically significant differences, suggesting that diagnostic performances of ACR list criteria are better in established arthritis. The specificity of ACR 1987 criteria in early RA is low, and these criteria should not be used as diagnostic tools. Sensitivity and specificity in established RA are higher, which reflects their use as classification criteria gold standard.

Reflective measurement of water concentration using millimeter wave illumination

NASA Astrophysics Data System (ADS)

Sung, Shijun; Bennett, David; Taylor, Zachary; Bajwa, Neha; Tewari, Priyamvada; Maccabi, Ashkan; Culjat, Martin; Singh, Rahul; Grundfest, Warren

2011-04-01

THz and millimeter wave technology have shown the potential to become a valuable medical imaging tool because of its sensitivity to water and safe, non-ionizing photon energy. Using the high dielectric constant of water in these frequency bands, reflectionmode THz sensing systems can be employed to measure water content in a target with high sensitivity. This phenomenology may lead to the development of clinical systems to measure the hydration state of biological targets. Such measurements may be useful in fast and convenient diagnosis of conditions whose symptoms can be characterized by changes in water concentration such as skin burns, dehydration, or chemical exposure. To explore millimeter wave sensitivity to hydration, a reflectometry system is constructed to make water concentration measurements at 100 GHz, and the minimum detectable water concentration difference is measured. This system employs a 100 GHz Gunn diode source and Golay cell detector to perform point reflectivity measurements of a wetted polypropylene towel as it dries on a mass balance. A noise limited, minimum detectable concentration difference of less than 0.5% by mass can be detected in water concentrations ranging from 70% to 80%. This sensitivity is sufficient to detect hydration changes caused by many diseases and pathologies and may be useful in the future as a diagnostic tool for the assessment of burns and other surface pathologies.

[Diagnostic value of cardiac magnetic resonance in patients with acute viral myocarditis].

PubMed

Ouyang, Haichun; Chen, Haixiong; Hu, Yunzhao; Wu, Yanxian; Li, Wensheng; Chen, Yuying; Cen, Yujian

2014-11-01

To assess the diagnostic value of cardiac magnetic resonance (CMR) in patients with acute viral myocarditis. Thirty patients with suspected acute viral myocarditis admitted in first people's hospital of Shunde from June 2011 to June 2013 were included in this prospective study. The diagnostic sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of acute viral myocarditis were evaluated by clinical diagnosis. Diagnostic value among different scan methods and Lake Louise criteria were compared. Acute viral myocarditis was diagnosed in 63.33% (19/30) patients.Values for sensitivity, specificity, PPV, NPV, and diagnostic accuracy within the overall cohort were 57.89%, 72.73%, 78.57%, 50.00%, 63.33%, respectively by edema imaging (ER).Values for sensitivity, specificity, PPV, NPV, and diagnostic accuracy within the overall cohort were 78.95%, 63.64%, 78.95%, 63.64%, 73.33%, respectively using global relative enhancement (gRE).Values for sensitivity, specificity, PPV, NPV, and diagnostic accuracy within the overall cohort were 78.95%, 54.55%, 75.00%, 60.00%, 70.00%, respectively using late gadolinium enhancement (LGE) criteria.Values for sensitivity, specificity, PPV, NPV, and diagnostic accuracy within the overall cohort were 84.21%, 81.82%, 88.89%, 75.00%, 83.33% using Lake Louise criteria. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy using Lake Louise criteria were significantly higher than using ER, gRE, LGE alone(all P < 0.05).Specificity was higher using ER than using gRE and LGE (both P < 0.05). The sensitivity, NPV, and diagnostic accuracy were significantly higher using gRE than using ER (all P < 0.05) and was similar as using LGE (all P > 0.05). Cardiac magnetic resonance is an excellent imaging modality for the diagnosis of acute viral myocarditis.

Exfoliative cytology: a helpful tool for the diagnosis of paracoccidioidomycosis.

PubMed

Cardoso, S V; Moreti, M M; Costa, I M; Loyola, A M

2001-07-01

To describe the main cytological findings associated with smears collected from oral lesions of paracoccidioidomycosis and to appraise the use of cytology as a diagnostic tool for the disease. Cytological smears and biopsies were collected from 40 lesions with a clinical suspicion of paracoccidioidomycosis. Evaluation of the sensitivity, specificity, positive and negative predictive values, accuracy and the positive likeness ratio of the oral smear when compared with the histological diagnosis, was performed. The latter is considered the 'gold standard' for comparison. The main morphological findings were the rounded-shaped, birefringent and multiple-budded fungi, Langhans' giant cells and epithelioid cells. The following associative measures were found: sensitivity, 67.9%; specificity, 91.7%; positive predictive value, 95.0%; negative predictive value, 55.0%; accuracy, 75.0%; and positive likeness ratio, 8.14. The cytological findings of paracoccidioidomycosis are characteristic and cytology is accurate in the diagnosis of the disease. Positive patients should be treated. Negative patients should be submitted to biopsy to confirm or to dismiss the diagnosis of this mycosis.

Design and validation of a new ratiometric intracellular pH imaging probe using lanthanide-doped upconverting nanoparticles.

PubMed

Du, Shuoren; Hernández-Gil, Javier; Dong, Hao; Zheng, Xiaoyu; Lyu, Guangming; Bañobre-López, Manuel; Gallo, Juan; Sun, Ling-Dong; Yan, Chun-Hua; Long, Nicholas J

2017-10-17

pH homeostasis is strictly controlled at a subcellular level. A deregulation of the intra/extra/subcellular pH environment is associated with a number of diseases and as such, the monitoring of the pH state of cells and tissues is a valuable diagnostic tool. To date, only a few tools have been developed to measure the pH in living cells with the spatial resolution needed for intracellular imaging. Among the techniques available, only optical imaging offers enough resolution and biocompatibility to be proposed for subcellular pH monitoring. We present herein a ratiometric probe based on upconversion nanoparticles modified with a pH sensitive moiety for the quantitative imaging of pH at the subcellular level in living cells. This system provides the properties required for live cell quantitative imaging i.e. positive cellular uptake, biocompatibility, long wavelength excitation, sensitive response to pH within a biologically relevant range, and self-referenced signal.

Broad-range (pan) Salmonella and Salmonella serotype typhi-specific real-time PCR assays: potential tools for the clinical microbiologist.

PubMed

Farrell, John J; Doyle, Laura J; Addison, Rachel M; Reller, L Barth; Hall, Geraldine S; Procop, Gary W

2005-03-01

We describe broad-range salmonellae (ie, Salmonella) and Salmonella serotype Typhi-specific LightCycler (Roche Diagnostics, Indianapolis, IN) real-time polymerase chain reaction assays. We validated these with a battery of 280 bacteria, 108 of which were salmonellae representing 20 serotypes. In addition, 298 isolates from 170 clinical specimens that were suspected to possibly represent Salmonella were tested with the pan- Salmonella assay. Finally, the pan-Salmonella assay also was used to test DNA extracts from 101 archived, frozen stool specimens, 55 of which were culture-positive for salmonellae. Both assays were 100% sensitive and specific when cultured isolates of the battery were tested. The pan- Salmonella assay also characterized correctly all salmonellae on the primary isolation agar and was 96% sensitive (53/55) and 96% specific (49/51) when nucleic acid extracts from direct stool specimens were tested. These assays represent potential tools the clinical microbiologist could use to screen suspect isolates or stool specimens for Salmonella.

Accuracy of biochemical markers for predicting nasogastric tube placement in adults--a systematic review of diagnostic studies.

PubMed

Fernandez, Ritin S; Chau, Janita Pak-Chun; Thompson, David R; Griffiths, Rhonda; Lo, Hoi-Shan

2010-08-01

The objective of this study was to investigate the diagnostic performance of biochemical tests used to determine placement of nasogastric (NG) tubes after insertion in adults. A systematic review of diagnostic studies was undertaken. A literature search of the bibliographic databases and the World Wide Web was performed to locate original diagnostic studies in English or Chinese on biochemical markers for detecting NG tube location. Studies in which one or more different tests were evaluated with a reference standard, and diagnostic values were reported or could be calculated were included. Two reviewers independently checked all abstracts and full text studies for inclusion criteria. Included studies were assessed for their quality using the QUADAS tool. Study features and diagnostic values were extracted from the included studies. Of the 10 studies included in this review, seven investigated the diagnostic accuracy of pH, one investigated the diagnostic accuracy of pH and bilirubin respectively, two a combination of pH and bilirubin and one a combination of pH, pepsin and trypsin levels in identifying NG tube location. All studies used X-rays as the reference standard for comparison. Pooled results demonstrated that a pH of

Development of class model based on blood biochemical parameters as a diagnostic tool of PSE meat.

PubMed

Qu, Daofeng; Zhou, Xu; Yang, Feng; Tian, Shiyi; Zhang, Xiaojun; Ma, Lin; Han, Jianzhong

2017-06-01

A fast, sensitive and effective method based on the blood biochemical parameters for the detection of PSE meat was developed in this study. A total of 200 pigs were slaughtered in the same slaughterhouse. Meat quality was evaluated by measuring pH, electrical conductivity and color at 45min, 2h and 24h after slaughtering in M. longissimus thoracis et lumborum (LD). Blood biochemical parameters were determined in blood samples collected during carcass bleeding. Principal component analysis (PCA) biplot showed that high levels of exsanguination Creatine Kinase, Lactate Dehydrogenase, Aspertate aminotransferase, blood glucose and lactate were associated with the PSE meat, and the five biochemical parameters were found to be good indicators of PSE meat Discriminant function analysis (DFA) was able to clearly identify PSE meat using the five biochemical parameters as input data, and the class model is an effective diagnostic tool in pigs which can be used to detect the PSE meat and reduce economic loss for the company. Copyright © 2017 Elsevier Ltd. All rights reserved.

Diagnostic performance of confocal laser endomicroscopy for optical diagnosis of gastric intestinal metaplasia: a meta-analysis.

PubMed

He, Xing-Kang; Liu, Dan; Sun, Lei-Min

2016-09-05

Gastric intestinal metaplasia (IM) is generally considered as a precancerous condition, a related risk factor for intestinal-type gastric cancer. However, an accurate endoscopic diagnosis of IM is a clinical challenge. Confocal Laser Endomicroscopy (CLE) is a newly technique that can provide real-time magnified images and visualize tissues at cellular or subcellular levels. The aim of this study is to clarify the diagnostic value of CLE in detection of IM in patients at high risk of gastric cancer. Systematic literature searches up to April 2015 in PubMed, Embase, Web of Science, Cochrane Library databases were conducted by two reviewers independently. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was applied to assess study quality and to reduce potential bias. A meta-analysis using Meta-Disc (version 1.4) and STATA software (version 13) was performed. A total of four studies enrolled 218 patients and 579 lesions were included in this meta-analysis. On per-lesion basis, the pooled sensitivity and specificity of CLE were 0.97(95 % confidence interval (CI) = 0.94-0.98) and 0.94 (95 % CI = 0.91-0.97) respectively. The pooled positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 15.20 (95 % CI = 9.46-24.41) and 0.04 (95 % CI = 0.02-0.07) respectively. The pooled diagnostic odds ratio (DOR) was 479.59 (95 % CI = 205.64-1118.51) and summary receiver operating curve (SROC) area under the curve was 0.9884. There was no statistical significance of publication bias. CLE is a promising endoscopic tool in the detection of IM with the relatively high diagnostic value in patients at high risk of gastric cancer.

Nearest Neighbor Classification Using a Density Sensitive Distance Measurement

DTIC Science & Technology

2009-09-01

both the proposed density sensitive distance measurement and Euclidean distance are compared on the Wisconsin Diagnostic Breast Cancer dataset and...proposed density sensitive distance measurement and Euclidean distance are compared on the Wisconsin Diagnostic Breast Cancer dataset and the MNIST...35 1. The Wisconsin Diagnostic Breast Cancer (WDBC) Dataset..........35 2. The

Receiver operating characteristic (ROC) curves: review of methods with applications in diagnostic medicine

NASA Astrophysics Data System (ADS)

Obuchowski, Nancy A.; Bullen, Jennifer A.

2018-04-01

Receiver operating characteristic (ROC) analysis is a tool used to describe the discrimination accuracy of a diagnostic test or prediction model. While sensitivity and specificity are the basic metrics of accuracy, they have many limitations when characterizing test accuracy, particularly when comparing the accuracies of competing tests. In this article we review the basic study design features of ROC studies, illustrate sample size calculations, present statistical methods for measuring and comparing accuracy, and highlight commonly used ROC software. We include descriptions of multi-reader ROC study design and analysis, address frequently seen problems of verification and location bias, discuss clustered data, and provide strategies for testing endpoints in ROC studies. The methods are illustrated with a study of transmission ultrasound for diagnosing breast lesions.

Amplitude Integrated Electroencephalography Compared With Conventional Video EEG for Neonatal Seizure Detection: A Diagnostic Accuracy Study.

PubMed

Rakshasbhuvankar, Abhijeet; Rao, Shripada; Palumbo, Linda; Ghosh, Soumya; Nagarajan, Lakshmi

2017-08-01

This diagnostic accuracy study compared the accuracy of seizure detection by amplitude-integrated electroencephalography with the criterion standard conventional video EEG in term and near-term infants at risk of seizures. Simultaneous recording of amplitude-integrated EEG (2-channel amplitude-integrated EEG with raw trace) and video EEG was done for 24 hours for each infant. Amplitude-integrated EEG was interpreted by a neonatologist; video EEG was interpreted by a neurologist independently. Thirty-five infants were included in the analysis. In the 7 infants with seizures on video EEG, there were 169 seizure episodes on video EEG, of which only 57 were identified by amplitude-integrated EEG. Amplitude-integrated EEG had a sensitivity of 33.7% for individual seizure detection. Amplitude-integrated EEG had an 86% sensitivity for detection of babies with seizures; however, it was nonspecific, in that 50% of infants with seizures detected by amplitude-integrated EEG did not have true seizures by video EEG. In conclusion, our study suggests that amplitude-integrated EEG is a poor screening tool for neonatal seizures.

Are current case-finding methods under-diagnosing tuberculosis among women in Myanmar? An analysis of operational data from Yangon and the nationwide prevalence survey.

PubMed

Khan, M S; Khine, T M; Hutchison, C; Coker, R J; Hane, K M; Innes, A L; Aung, S

2016-03-03

Although there is a large increase in investment for tuberculosis control in Myanmar, there are few operational analyses to inform policies. Only 34% of nationally reported cases are from women. In this study, we investigate sex differences in tuberculosis diagnoses in Myanmar in order to identify potential health systems barriers that may be driving lower tuberculosis case finding among women. From October 2014 to March 2015, we systematically collected data on all new adult smear positive tuberculosis cases in ten township health centres across Yangon, the largest city in Myanmar, to produce an electronic tuberculosis database. We conducted a descriptive cross-sectional analysis of sex differences in tuberculosis diagnoses at the township health centres. We also analysed national prevalence survey data to calculate additional case finding in men and women by using sputum culture when smear microscopy was negative, and estimated the sex-specific impact of using a more sensitive diagnostic tool at township health centres. Overall, only 514 (30%) out of 1371 new smear positive tuberculosis patients diagnosed at the township health centres were female. The proportion of female patients varied by township (from 21% to 37%, p = 0.0172), month of diagnosis (37% in February 2015 and 23% in March 2015 p = 0.0004) and age group (26% in 25-64 years and 49% in 18-25 years, p < 0.0001). Smear microscopy grading of sputum specimens was not substantially different between sexes. The prevalence survey analysis indicated that the use of a more sensitive diagnostic tool could result in the proportion of females diagnosed at township health centres increasing to 36% from 30%. Our study, which is the first to systematically compile and analyse routine operational data from tuberculosis diagnostic centres in Myanmar, found that substantially fewer women than men were diagnosed in all study townships. The sex ratio of newly diagnosed cases varied by age group, month of diagnosis and township of diagnosis. Low sensitivity of tuberculosis diagnosis may lead to a potential under-diagnosis of tuberculosis among women.

Real-time PCR as a surveillance tool for the detection of Trichinella infection in muscle samples from wildlife.

PubMed

Cuttell, Leigh; Corley, Sean W; Gray, Christian P; Vanderlinde, Paul B; Jackson, Louise A; Traub, Rebecca J

2012-09-10

Trichinella nematodes are the causative agent of trichinellosis, a meat-borne zoonosis acquired by consuming undercooked, infected meat. Although most human infections are sourced from the domestic environment, the majority of Trichinella parasites circulate in the natural environment in carnivorous and scavenging wildlife. Surveillance using reliable and accurate diagnostic tools to detect Trichinella parasites in wildlife hosts is necessary to evaluate the prevalence and risk of transmission from wildlife to humans. Real-time PCR assays have previously been developed for the detection of European Trichinella species in commercial pork and wild fox muscle samples. We have expanded on the use of real-time PCR in Trichinella detection by developing an improved extraction method and SYBR green assay that detects all known Trichinella species in muscle samples from a greater variety of wildlife. We simulated low-level Trichinella infections in wild pig, fox, saltwater crocodile, wild cat and a native Australian marsupial using Trichinella pseudospiralis or Trichinella papuae ethanol-fixed larvae. Trichinella-specific primers targeted a conserved region of the small subunit of the ribosomal RNA and were tested for specificity against host and other parasite genomic DNAs. The analytical sensitivity of the assay was at least 100 fg using pure genomic T. pseudospiralis DNA serially diluted in water. The diagnostic sensitivity of the assay was evaluated by spiking 10 g of each host muscle with T. pseudospiralis or T. papuae larvae at representative infections of 1.0, 0.5 and 0.1 larvae per gram, and shown to detect larvae at the lowest infection rate. A field sample evaluation on naturally infected muscle samples of wild pigs and Tasmanian devils showed complete agreement with the EU reference artificial digestion method (k-value=1.00). Positive amplification of mouse tissue experimentally infected with T. spiralis indicated the assay could also be used on encapsulated species in situ. This real-time PCR assay offers an alternative highly specific and sensitive diagnostic method for use in Trichinella wildlife surveillance and could be adapted to wildlife hosts of any region. Copyright © 2012 Elsevier B.V. All rights reserved.

Assessing Predictive Validity of Pressure Ulcer Risk Scales- A Systematic Review and Meta-Analysis

PubMed Central

PARK, Seong-Hi; LEE, Hea Shoon

2016-01-01

Background: The purpose of this study was to present a scientific reason for pressure ulcer risk scales: Cubbin& Jackson modified Braden, Norton, and Waterlow, as a nursing diagnosis tool by utilizing predictive validity of pressure sores. Methods: Articles published between 1966 and 2013 from periodicals indexed in the Ovid Medline, Embase, CINAHL, KoreaMed, NDSL, and other databases were selected using the key word “pressure ulcer”. QUADAS-II was applied for assessment for internal validity of the diagnostic studies. Selected studies were analyzed using meta-analysis with MetaDisc 1.4. Results: Seventeen diagnostic studies with high methodological quality, involving 5,185 patients, were included. In the results of the meta-analysis, sROC AUC of Braden, Norton, and Waterflow scale was over 0.7, showing moderate predictive validity, but they have limited interpretation due to significant differences between studies. In addition, Waterlow scale is insufficient as a screening tool owing to low sensitivity compared with other scales. Conclusion: The contemporary pressure ulcer risk scale is not suitable for uninform practice on patients under standardized criteria. Therefore, in order to provide more effective nursing care for bedsores, a new or modified pressure ulcer risk scale should be developed upon strength and weaknesses of existing tools. PMID:27114977

Investigation of the subcellular architecture of L7 neurons of Aplysia californica using magnetic resonance microscopy (MRM) at 7.8 microns.

PubMed

Lee, Choong H; Flint, Jeremy J; Hansen, Brian; Blackband, Stephen J

2015-06-10

Magnetic resonance microscopy (MRM) is a non-invasive diagnostic tool which is well-suited to directly resolve cellular structures in ex vivo and in vitro tissues without use of exogenous contrast agents. Recent advances in its capability to visualize mammalian cellular structure in intact tissues have reinvigorated analytical interest in aquatic cell models whose previous findings warrant up-to-date validation of subcellular components. Even if the sensitivity of MRM is less than other microscopic technologies, its strength lies in that it relies on the same image contrast mechanisms as clinical MRI which make it a unique tool for improving our ability to interpret human diagnostic imaging through high resolution studies of well-controlled biological model systems. Here, we investigate the subcellular MR signal characteristics of isolated cells of Aplysia californica at an in-plane resolution of 7.8 μm. In addition, direct correlation and positive identification of subcellular architecture in the cells is achieved through well-established histology. We hope this methodology will serve as the groundwork for studying pathophysiological changes through perturbation studies and allow for development of disease-specific cellular modeling tools. Such an approach promises to reveal the MR contrast changes underlying cellular mechanisms in various human diseases, for example in ischemic stroke.

Volatile metabolomic signature of human breast cancer cell lines

PubMed Central

Silva, Catarina L.; Perestrelo, Rosa; Silva, Pedro; Tomás, Helena; Câmara, José S.

2017-01-01

Breast cancer (BC) remains the most prevalent oncologic pathology in women, causing huge psychological, economic and social impacts on our society. Currently, the available diagnostic tools have limited sensitivity and specificity. Metabolome analysis has emerged as a powerful tool for obtaining information about the biological processes that occur in organisms, and is a useful platform for discovering new biomarkers or make disease diagnosis using different biofluids. Volatile organic compounds (VOCs) from the headspace of cultured BC cells and normal human mammary epithelial cells, were collected by headspace solid-phase microextraction (HS-SPME) and analyzed by gas chromatography combined with mass spectrometry (GC–MS), thus defining a volatile metabolomic signature. 2-Pentanone, 2-heptanone, 3-methyl-3-buten-1-ol, ethyl acetate, ethyl propanoate and 2-methyl butanoate were detected only in cultured BC cell lines. Multivariate statistical methods were used to verify the volatomic differences between BC cell lines and normal cells in order to find a set of specific VOCs that could be associated with BC, providing comprehensive insight into VOCs as potential cancer biomarkers. The establishment of the volatile fingerprint of BC cell lines presents a powerful approach to find endogenous VOCs that could be used to improve the BC diagnostic tools and explore the associated metabolomic pathways. PMID:28256598

Urinary Proteomic Biomarkers for Diagnosis and Risk Stratification of Autosomal Dominant Polycystic Kidney Disease: A Multicentric Study

PubMed Central

Kistler, Andreas D.; Serra, Andreas L.; Siwy, Justyna; Poster, Diane; Krauer, Fabienne; Torres, Vicente E.; Mrug, Michal; Grantham, Jared J.; Bae, Kyongtae T.; Bost, James E.; Mullen, William; Wüthrich, Rudolf P.; Mischak, Harald; Chapman, Arlene B.

2013-01-01

Treatment options for autosomal dominant polycystic kidney disease (ADPKD) will likely become available in the near future, hence reliable diagnostic and prognostic biomarkers for the disease are strongly needed. Here, we aimed to define urinary proteomic patterns in ADPKD patients, which aid diagnosis and risk stratification. By capillary electrophoresis online coupled to mass spectrometry (CE-MS), we compared the urinary peptidome of 41 ADPKD patients to 189 healthy controls and identified 657 peptides with significantly altered excretion, of which 209 could be sequenced using tandem mass spectrometry. A support-vector-machine based diagnostic biomarker model based on the 142 most consistent peptide markers achieved a diagnostic sensitivity of 84.5% and specificity of 94.2% in an independent validation cohort, consisting of 251 ADPKD patients from five different centers and 86 healthy controls. The proteomic alterations in ADPKD included, but were not limited to markers previously associated with acute kidney injury (AKI). The diagnostic biomarker model was highly specific for ADPKD when tested in a cohort consisting of 481 patients with a variety of renal and extrarenal diseases, including AKI. Similar to ultrasound, sensitivity and specificity of the diagnostic score depended on patient age and genotype. We were furthermore able to identify biomarkers for disease severity and progression. A proteomic severity score was developed to predict height adjusted total kidney volume (htTKV) based on proteomic analysis of 134 ADPKD patients and showed a correlation of r = 0.415 (p<0.0001) with htTKV in an independent validation cohort consisting of 158 ADPKD patients. In conclusion, the performance of peptidomic biomarker scores is superior to any other biochemical markers of ADPKD and the proteomic biomarker patterns are a promising tool for prognostic evaluation of ADPKD. PMID:23326375

A Systematic Review and Meta-analysis of the Diagnostic Accuracy of Prostate Health Index and 4-Kallikrein Panel Score in Predicting Overall and High-grade Prostate Cancer.

PubMed

Russo, Giorgio Ivan; Regis, Federica; Castelli, Tommaso; Favilla, Vincenzo; Privitera, Salvatore; Giardina, Raimondo; Cimino, Sebastiano; Morgia, Giuseppe

2017-08-01

Markers for prostate cancer (PCa) have progressed over recent years. In particular, the prostate health index (PHI) and the 4-kallikrein (4K) panel have been demonstrated to improve the diagnosis of PCa. We aimed to review the diagnostic accuracy of PHI and the 4K panel for PCa detection. We performed a systematic literature search of PubMed, EMBASE, Cochrane, and Academic One File databases until July 2016. We included diagnostic accuracy studies that used PHI or 4K panel for the diagnosis of PCa or high-grade PCa. The methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Twenty-eight studies including 16,762 patients have been included for the analysis. The pooled data showed a sensitivity of 0.89 and 0.74 for PHI and 4K panel, respectively, for PCa detection and a pooled specificity of 0.34 and 0.60 for PHI and 4K panel, respectively. The derived area under the curve (AUC) from the hierarchical summary receiver operating characteristic (HSROC) showed an accuracy of 0.76 and 0.72 for PHI and 4K panel respectively. For high-grade PCa detection, the pooled sensitivity was 0.93 and 0.87 for PHI and 4K panel, respectively, whereas the pooled specificity was 0.34 and 0.61 for PHI and 4K panel, respectively. The derived AUC from the HSROC showed an accuracy of 0.82 and 0.81 for PHI and 4K panel, respectively. Both PHI and the 4K panel provided good diagnostic accuracy in detecting overall and high-grade PCa. Copyright © 2016 Elsevier Inc. All rights reserved.

The value of FDG PET/CT for follow-up of patients with melanoma: a retrospective analysis

PubMed Central

Vensby, Philip H; Schmidt, Grethe; Kjær, Andreas; Fischer, Barbara M

2017-01-01

The incidence of melanoma (MM) is among the fastest rising cancers in the western countries. Positron Emission Tomography with Computed Tomography (PET/CT) is a valuable non-invasive tool for the diagnosis and staging of patients with MM. However, research on the value of PET/CT in follow-up of melanoma patients is limited. This study assesses the diagnostic value of PET/CT for follow-up after melanoma surgery. This retrospective study includes patients with MM who performed at least one PET/CT scan after initial surgery and staging. PET/CT findings were compared to histology, MRI or fine needle aspiration (FNA) to estimate the diagnostic accuracy. The diagnostic performance of PET/CT performed in patients with and without a clinical suspicion of relapse was compared. 238 patients (526 scans) were included. Of the 526 scans 130 (25%) scans were PET-positive, 365 (69%) PET-negative, and 28 (5%) had equivocal findings. Sensitivity was 89% [0.82-0.94], specificity 92% [0.89-0.95], positive and negative predictive values of 78% [0.70-0.84] and 97% [0.94-0.98] respectively. When stratified for reason of referral there was no statistical significant difference in the diagnostic accuracy of PET/CT between patients referred with or without a clinical suspicion of relapse. This study demonstrates that PET/CT despite a moderate sensitivity has a high negative predictive value in the follow-up of melanoma patients. Thus, a negative PET/CT-scan essentially rules out relapse. However, the frequency of false positive findings is relatively high, especially among patients undergoing a “routine” PET/CT with no clinical suspicion of relapse, potentially causing anxiety and leading to further diagnostic procedures. PMID:29348980

The value of FDG PET/CT for follow-up of patients with melanoma: a retrospective analysis.

PubMed

Vensby, Philip H; Schmidt, Grethe; Kjær, Andreas; Fischer, Barbara M

2017-01-01

The incidence of melanoma (MM) is among the fastest rising cancers in the western countries. Positron Emission Tomography with Computed Tomography (PET/CT) is a valuable non-invasive tool for the diagnosis and staging of patients with MM. However, research on the value of PET/CT in follow-up of melanoma patients is limited. This study assesses the diagnostic value of PET/CT for follow-up after melanoma surgery. This retrospective study includes patients with MM who performed at least one PET/CT scan after initial surgery and staging. PET/CT findings were compared to histology, MRI or fine needle aspiration (FNA) to estimate the diagnostic accuracy. The diagnostic performance of PET/CT performed in patients with and without a clinical suspicion of relapse was compared. 238 patients (526 scans) were included. Of the 526 scans 130 (25%) scans were PET-positive, 365 (69%) PET-negative, and 28 (5%) had equivocal findings. Sensitivity was 89% [0.82-0.94], specificity 92% [0.89-0.95], positive and negative predictive values of 78% [0.70-0.84] and 97% [0.94-0.98] respectively. When stratified for reason of referral there was no statistical significant difference in the diagnostic accuracy of PET/CT between patients referred with or without a clinical suspicion of relapse. This study demonstrates that PET/CT despite a moderate sensitivity has a high negative predictive value in the follow-up of melanoma patients. Thus, a negative PET/CT-scan essentially rules out relapse. However, the frequency of false positive findings is relatively high, especially among patients undergoing a "routine" PET/CT with no clinical suspicion of relapse, potentially causing anxiety and leading to further diagnostic procedures.

Diagnostic accuracy of the Patient Health Questionnaire-9 for assessment of depression in type II diabetes mellitus and/or coronary heart disease in primary care.

PubMed

van der Zwaan, G Lennart; van Dijk, Susan E M; Adriaanse, Marcel C; van Marwijk, Harm W J; van Tulder, Maurits W; Pols, Alide D; Bosmans, Judith E

2016-01-15

Depression is common among type 2 diabetes mellitus (DM2)/coronary heart disease (CHD) patients and is associated with adverse health effects. A promising strategy to reduce burden of disease is to identify patients at risk for depression in order to offer indicated prevention. This study aims to assess the diagnostic accuracy of the Patient Health Questionnaire-9 (PHQ-9) to be used as a tool to identify high risk patients. In this cross-sectional study, 586 consecutive DM2/CHD patients aged >18 were recruited through 23 general practices. PHQ-9 outcomes were compared to the Mini International Neuropsychiatric Interview (MINI), which was considered the reference standard. Diagnostic accuracy was evaluated for minor and major depression, comparing both sum- and algorithm based PHQ-9 scores. For minor depression, the optimal cut-off score was 8 (sensitivity 71%, specificity 71% and an AUC of 0.74). For major depression, the optimal cut-off score was 10 resulting in a sensitivity of 84%, a specificity of 82%, and an AUC of 0.88. The positive predictive value of the PHQ-9 algorithm for diagnosing minor and major depression was 25% and 33%, respectively. Two main limitations apply. MINI Interviewers were not blinded for PHQ-9 scores and less than 10% of all invited patients could be included in the analyses. This could have resulted in biased outcomes. The PHQ-9 sum score performs well in identifying patients at high risk of minor and major depression. However, the PHQ-9 showed suboptimal results for diagnostic purposes. Therefore, it is recommended to combine the use of the PHQ-9 with further diagnostics to identify depression. Copyright © 2015 Elsevier B.V. All rights reserved.