Johnson, Cheryl C; Fonner, Virginia; Sands, Anita; Ford, Nathan; Obermeyer, Carla Mahklouf; Tsui, Sharon; Wong, Vincent; Baggaley, Rachel
2017-08-29
In accordance with global testing and treatment targets, many countries are seeking ways to reach the "90-90-90" goals, starting with diagnosing 90% of all people with HIV. Quality HIV testing services are needed to enable people with HIV to be diagnosed and linked to treatment as early as possible. It is essential that opportunities to reach people with undiagnosed HIV are not missed, diagnoses are correct and HIV-negative individuals are not inadvertently initiated on life-long treatment. We conducted this systematic review to assess the magnitude of misdiagnosis and to describe poor HIV testing practices using rapid diagnostic tests. We systematically searched peer-reviewed articles, abstracts and grey literature published from 1 January 1990 to 19 April 2017. Studies were included if they used at least two rapid diagnostic tests and reported on HIV misdiagnosis, factors related to potential misdiagnosis or described quality issues and errors related to HIV testing. Sixty-four studies were included in this review. A small proportion of false positive (median 3.1%, interquartile range (IQR): 0.4-5.2%) and false negative (median: 0.4%, IQR: 0-3.9%) diagnoses were identified. Suboptimal testing strategies were the most common factor in studies reporting misdiagnoses, particularly false positive diagnoses due to using a "tiebreaker" test to resolve discrepant test results. A substantial proportion of false negative diagnoses were related to retesting among people on antiretroviral therapy. Conclusions HIV testing errors and poor practices, particularly those resulting in false positive or false negative diagnoses, do occur but are preventable. Efforts to accelerate HIV diagnosis and linkage to treatment should be complemented by efforts to improve the quality of HIV testing services and strengthen the quality management systems, particularly the use of validated testing algorithms and strategies, retesting people diagnosed with HIV before initiating treatment and providing clear messages to people with HIV on treatment on the risk of a "false negative" test result.
Johnson, Cheryl C.; Fonner, Virginia; Sands, Anita; Ford, Nathan; Obermeyer, Carla Mahklouf; Tsui, Sharon; Wong, Vincent; Baggaley, Rachel
2017-01-01
Abstract Introduction: In accordance with global testing and treatment targets, many countries are seeking ways to reach the “90-90-90” goals, starting with diagnosing 90% of all people with HIV. Quality HIV testing services are needed to enable people with HIV to be diagnosed and linked to treatment as early as possible. It is essential that opportunities to reach people with undiagnosed HIV are not missed, diagnoses are correct and HIV-negative individuals are not inadvertently initiated on life-long treatment. We conducted this systematic review to assess the magnitude of misdiagnosis and to describe poor HIV testing practices using rapid diagnostic tests. Methods: We systematically searched peer-reviewed articles, abstracts and grey literature published from 1 January 1990 to 19 April 2017. Studies were included if they used at least two rapid diagnostic tests and reported on HIV misdiagnosis, factors related to potential misdiagnosis or described quality issues and errors related to HIV testing. Results: Sixty-four studies were included in this review. A small proportion of false positive (median 3.1%, interquartile range (IQR): 0.4-5.2%) and false negative (median: 0.4%, IQR: 0-3.9%) diagnoses were identified. Suboptimal testing strategies were the most common factor in studies reporting misdiagnoses, particularly false positive diagnoses due to using a “tiebreaker” test to resolve discrepant test results. A substantial proportion of false negative diagnoses were related to retesting among people on antiretroviral therapy. Conclusions: HIV testing errors and poor practices, particularly those resulting in false positive or false negative diagnoses, do occur but are preventable. Efforts to accelerate HIV diagnosis and linkage to treatment should be complemented by efforts to improve the quality of HIV testing services and strengthen the quality management systems, particularly the use of validated testing algorithms and strategies, retesting people diagnosed with HIV before initiating treatment and providing clear messages to people with HIV on treatment on the risk of a “false negative” test result. PMID:28872271
Analysis of false results in a series of 835 fine needle aspirates of breast lesions.
Willis, S L; Ramzy, I
1995-01-01
To analyze cases of false diagnoses from a large series to help increase the accuracy of fine needle aspiration of palpable breast lesions. The results of FNA of 835 palpable breast lesions were analyzed to determine the reasons for false positive, false negative and false suspicious diagnoses. Of the 835 aspirates, 174 were reported as positive, 549 as negative and 66 as suspicious or atypical but not diagnostic of malignancy. Forty-six cases were considered unsatisfactory. Tissue was available for comparison in 286 cases. The cytologic diagnoses in these cases were reported as follows: positive, 125 (43.7%); suspicious, 33 (11.5%); atypical, 18 (6.2%); negative, 92 (32%); and unsatisfactory, 18 (6.2%). There was one false positive diagnosis, yielding a false positive rate of 0.8%. This lesion was a case of fibrocystic change with hyperplasia, focal fat necrosis and reparative atypia. There were 14 false negative cases, resulting in a false negative rate of 13.2%. Nearly all these cases were sampling errors and included infiltrating ductal carcinomas (9), ductal carcinomas in situ (2), infiltrating lobular carcinomas (2) and tubular carcinoma (1). Most of the suspicious and atypical lesions proved to be carcinomas (35/50). The remainder were fibroadenomas (6), fibrocystic change (4), gynecomastia (2), adenosis (2) and granulomatous mastitis (1). A positive diagnosis of malignancy by FNA is reliable in establishing the diagnosis and planning the treatment of breast cancer. The false-positive rate is very low, with only a single case reported in 835 aspirates. Most false negatives are due to sampling and not to interpretive difficulties. The category "suspicious but not diagnostic of malignancy" serves a useful purpose in management of patients with breast lumps.
Rui, Y; Han, M; Zhou, W; He, Q; Li, H; Li, P; Zhang, F; Shi, Y; Su, X
2018-06-06
To determine true negatives and characterise the variables associated with false-negative results when interpreting non-malignant results of computed tomography (CT)-guided lung biopsy. Nine hundred and fifty patients with initial non-malignant findings on their first transthoracic CT-guided core-needle biopsy (TTNB) were included in the study. Initial biopsy results were compared to definitive diagnoses established later. The negative predictive value (NPV) of non-malignant diseases upon initial TTNB was 83.6%. When the biopsy results indicated specific infection or benign tumour (n=225, 26.1%), they all were confirmed true negative for malignancy later. Only one inconclusive "granuloma" diagnosis was false negative. All 141 patients (141/861, 16.4%) who were false negative for malignancy were from the "infection not otherwise specified (NOS)", "inflammatory diseases", or "inconclusive" groups. Age (p=0.002), cancer history (p<0.001), target size (p=0.003), and pneumothorax during lung biopsy (p=0.003) were found to be significant predictors of false-negative results; 47.6% (410/861) of patients underwent additional invasive examinations to reach a final diagnosis. Ultimately, 52.7% (216/410) were successfully diagnosed. Specific infection, benign tumour, and granulomatous inflammation of first TTNBs were mostly true negative. Older age, history of cancer, larger target size, and pneumothorax were highly predictive of false-negative results for malignancies. In such cases, additional invasive examinations were frequently necessary to obtain final diagnoses. Copyright © 2018 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Clinical Features of Children With Autism Who Passed 18-Month Screening.
Øien, Roald A; Schjølberg, Synnve; Volkmar, Fred R; Shic, Frederick; Cicchetti, Domenic V; Nordahl-Hansen, Anders; Stenberg, Nina; Hornig, Mady; Havdahl, Alexandra; Øyen, Anne-Siri; Ventola, Pamela; Susser, Ezra S; Eisemann, Martin R; Chawarska, Katarzyna
2018-06-01
We compared sex-stratified developmental and temperamental profiles at 18 months in children screening negative for autism spectrum disorder (ASD) on the Modified Checklist for Autism in Toddlers (M-CHAT) but later receiving diagnoses of ASD (false-negative group) versus those without later ASD diagnoses (true-negative group). We included 68 197 screen-negative cases from the Norwegian Mother and Child Cohort Study (49.1% girls). Children were screened by using the 6 critical items of the M-CHAT at 18 months. Groups were compared on domains of the Ages and Stages Questionnaire and the Emotionality Activity Sociability Temperament Survey. Despite passing M-CHAT screening at 18 months, children in the false-negative group exhibited delays in social, communication, and motor skills compared with the true-negative group. Differences were more pronounced in girls. However, with regard to shyness, boys in the false-negative group were rated as more shy than their true-negative counterparts, but girls in the false-negative group were rated as less shy than their counterparts in the true-negative group. This is the first study to reveal that children who pass M-CHAT screening at 18 months and are later diagnosed with ASD exhibit delays in core social and communication areas as well as fine motor skills at 18 months. Differences appeared to be more pronounced in girls. With these findings, we underscore the need to enhance the understanding of early markers of ASD in boys and girls, as well as factors affecting parental report on early delays and abnormalities, to improve the sensitivity of screening instruments. Copyright © 2018 by the American Academy of Pediatrics.
Application of Immunosignatures for Diagnosis of Valley Fever
Navalkar, Krupa Arun; Johnston, Stephen Albert; Woodbury, Neal; Galgiani, John N.; Magee, D. Mitchell; Chicacz, Zbigniew
2014-01-01
Valley fever (VF) is difficult to diagnose, partly because the symptoms of VF are confounded with those of other community-acquired pneumonias. Confirmatory diagnostics detect IgM and IgG antibodies against coccidioidal antigens via immunodiffusion (ID). The false-negative rate can be as high as 50% to 70%, with 5% of symptomatic patients never showing detectable antibody levels. In this study, we tested whether the immunosignature diagnostic can resolve VF false negatives. An immunosignature is the pattern of antibody binding to random-sequence peptides on a peptide microarray. A 10,000-peptide microarray was first used to determine whether valley fever patients can be distinguished from 3 other cohorts with similar infections. After determining the VF-specific peptides, a small 96-peptide diagnostic array was created and tested. The performances of the 10,000-peptide array and the 96-peptide diagnostic array were compared to that of the ID diagnostic standard. The 10,000-peptide microarray classified the VF samples from the other 3 infections with 98% accuracy. It also classified VF false-negative patients with 100% sensitivity in a blinded test set versus 28% sensitivity for ID. The immunosignature microarray has potential for simultaneously distinguishing valley fever patients from those with other fungal or bacterial infections. The same 10,000-peptide array can diagnose VF false-negative patients with 100% sensitivity. The smaller 96-peptide diagnostic array was less specific for diagnosing false negatives. We conclude that the performance of the immunosignature diagnostic exceeds that of the existing standard, and the immunosignature can distinguish related infections and might be used in lieu of existing diagnostics. PMID:24964807
Engberts, Marian K; Goedbloed, Annelize F; van Haaften, Maarten; van Haaften, Mathilde; Boon, Mathilde E; Boon, Maarten E; Heintz, Peter M
2007-01-01
To determine the accuracy of the microscopic diagnosis of vulvovaginal candidiasis (presence of [pseudo] hyphae and blastospores) in stained vaginal smears in clinical practice. General practitioners trained in diagnosing vulvovaginal candidiasis performed microscopy of 324 stained vaginal smears. These smears were sent to the pathologist for confirmation of the microscopic diagnosis of the clinician; cytologic diagnosis by the pathologist was considered the gold standard. In 104 of the 342 cases Candida was established by the pathologist. The clinicians made 24 false positive and 50 false negative diagnoses of Candida. Sensitivity and specificity of the microscopic diagnoses of the clinicians were 52% and 89%, respectively. The most frequent reason for a false positive diagnosis was presence of hairs, whereas the most frequent reason for a false negative diagnosis was understaining of the smear. This study shows that even in stained smears it is difficult for clinicians to recognize blastospores and (pseudo)hyphae. Efforts are clearly needed to improve the quality of the clinical diagnosis of vulvovaginal candidiasis.
2014-01-01
Background This study aimed to better understand the supporting role that mutational profiling (MP) of DNA from microdissected cytology slides and supernatant specimens may play in the diagnosis of malignancy in fine-needle aspirates (FNA) and biliary brushing specimens from patients with pancreaticobiliary masses. Methods Cytology results were examined in a total of 30 patients with associated surgical (10) or clinical (20) outcomes. MP of DNA from microdissected cytology slides and from discarded supernatant fluid was analyzed in 26 patients with atypical, negative or indeterminate cytology. Results Cytology correctly diagnosed aggressive disease in 4 patients. Cytological diagnoses for the remaining 26 were as follows: 16 negative (9 false negative), 9 atypical, 1 indeterminate. MP correctly determined aggressive disease in 1 false negative cytology case and confirmed a negative cytology diagnosis in 7 of 7 cases of non-aggressive disease. Of the 9 atypical cytology cases, MP correctly diagnosed 7 as positive and 1 as negative for aggressive disease. One specimen that was indeterminate by cytology was correctly diagnosed as non-aggressive by MP. When first line malignant (positive) cytology results were combined with positive second line MP results, 12/21 cases of aggressive disease were identified, compared to 4/21 cases identified by positive cytology alone. Conclusions When first line cytology results were uncertain (atypical), questionable (negative), or not possible (non-diagnostic/indeterminate), MP provided additional information regarding the presence of aggressive disease. When used in conjunction with first line cytology, MP increased detection of aggressive disease without compromising specificity in patients that were difficult to diagnose by cytology alone. PMID:25084836
Sherlock Holmes and child psychopathology assessment approaches: the case of the false-positive.
Jensen, P S; Watanabe, H
1999-02-01
To explore the relative value of various methods of assessing childhood psychopathology, the authors compared 4 groups of children: those who met criteria for one or more DSM diagnoses and scored high on parent symptom checklists, those who met psychopathology criteria on either one of these two assessment approaches alone, and those who met no psychopathology assessment criterion. Parents of 201 children completed the Child Behavior Checklist (CBCL), after which children and parents were administered the Diagnostic Interview Schedule for Children (version 2.1). Children and parents also completed other survey measures and symptom report inventories. The 4 groups of children were compared against "external validators" to examine the merits of "false-positive" and "false-negative" cases. True-positive cases (those that met DSM criteria and scored high on the CBCL) differed significantly from the true-negative cases on most external validators. "False-positive" and "false-negative" cases had intermediate levels of most risk factors and external validators. "False-positive" cases were not normal per se because they scored significantly above the true-negative group on a number of risk factors and external validators. A similar but less marked pattern was noted for "false-negatives." Findings call into question whether cases with high symptom checklist scores despite no formal diagnoses should be considered "false-positive." Pending the availability of robust markers for mental illness, researchers and clinicians must resist the tendency to reify diagnostic categories or to engage in arcane debates about the superiority of one assessment approach over another.
Yang, Chi; Zhang, Shaojun; Yao, Lan; Fan, Lin
2018-05-01
Objective To investigate the diagnostic efficacy of an interferon-γ release assay, T-SPOT ® . TB, for diagnosing active tuberculosis (TB) and to identify risk factors for false-negative results. Methods This retrospective study enrolled consecutive patients with active TB and with non-TB respiratory diseases to evaluate the risk factors for false-negative results when using the T-SPOT ® . TB assay for the diagnosis of active TB. Patients with active TB were categorized as having confirmed pulmonary TB, clinically diagnosed pulmonary TB or extrapulmonary TB (EPTB). Results This study analysed 4964 consecutive patients; 2425 with active TB and 2539 with non-TB respiratory diseases. Multivariate logistic regression analyses identified the following five factors that were all associated with an increased false-negative rate with the T-SPOT ® . TB assay: increased age (odds ratio [OR] 1.018; 95% confidence interval [CI] 1.013, 1.024); decreased CD8+ count (OR 0.307; 95% CI 0.117, 0.803); negative sputum acid-fast bacilli (AFB) smear staining (OR 1.821; 95% CI 1.338, 2.477); negative mycobacterial cultures (OR 1.379; 95% CI 1.043, 1.824); and absence of EPTB (OR 1.291; 95% CI 1.026, 1.623). Conclusions Increased age, decreased CD8+ count, negative sputum AFB smear results, negative sputum mycobacterial cultures and absence of EPTB might lead to an increased false-negative rate when using the T-SPOT ® . TB assay.
Moatamed, Neda A; Naini, Bita V; Fathizadeh, Payman; Estrella, Julie; Apple, Sophia K
2009-10-01
The clinical diagnosis of a mass in the neck region encompasses a wide spectrum of differential diagnosis. Fine-needle aspiration is a quick and safe technique, which can provide useful information for initial assessment and further therapeutic measures. The aim of this retrospective study was to evaluate the performance characteristics of the fine-needle aspiration (FNA) in cystic neck lesions. Of 142 patients with FNA for cystic neck masses during 2002-2007, 92 cases were selected with a follow-up histologic diagnosis, excluding the cystic colloid nodule of the thyroid. The cases were divided into salivary gland cystic neck (37 patients) and non-salivary cystic neck (55 patients) mass groups. False-positive and false-negative diagnoses were applied only to the malignant lesions after confirmation by histopathology. In the first group, nine malignant and 28 benign diagnoses were made by FNA; of which three were false-negative. In the second group, there were nine malignant and 46 benign diagnoses with three false negatives. The overall performance of the FNA showed 76% sensitivity and 100% specificity. In conclusion, FNA of the cystic neck lesions offers an invaluable and highly specific initial diagnostic approach for the management of the patients. (c) 2009 Wiley-Liss, Inc.
Hocagil, Hilal; Hocagil, Abdullah Cüneyt; Karacabey, Sinan; Akkaya, Tuğba; Şimşek, Gözde; Sanrı, Erkman
2015-09-01
This study aimed to discuss the effectiveness of Pneumoscan working with micropower impulse radar (MIR) technology in diagnosing pneumothorax (PTX) in the emergency department. Patients with suspicion of PTX and indication for thorax tomography (CT) were included into the study. Findings of the Thorax CT were compared with the results of Pneumoscan. Chi-square and Fisher's exact tests were used in categorical variables. One hundred and fifteen patients were included into the study group; twelve patients presented with PTX diagnosed by CT, 10 of which were detected by Pneumoscan. Thirty-six true negative results, sixty-seven false positive results, and two false negative results were obtained, which resulted in an overall sensitivity of 83.3%, specificity of 35.0% for Pneumoscan. There was no statistically significant difference between the effectiveness of Pneumoscan and CT on the detection of PTX (p=0.33). There was no difference between the size of PTX diagnosed by CT and PTX diagnosed by Pneumoscan (p=0.47). There was no statistically significant difference between Pneumoscan and CT on detecting the localisation of the PTX (p=1.00). For the 10 cases diagnosed by Pneumoscan, mean chest wall thickness was determined as 50.3 mm while mean chest wall thickness for two false negatives diagnosed by Pneumoscan was 56.5 mm. However, no statistically significant difference was found between the chest wall thickness and the effectiveness of Pneumoscan on the detection of the PTX (p=0.77). Among sixty-seven false positives diagnosed by Pneumoscan, 46.3% had additional medical signs such as bronchiectasis, pulmonary consolidation, pulmonary edema or pulmonary tumor when they had a reading with CT. The relationship between having additional medical signs at the reading with CT and the effectiveness of Pneumoscan on the detection of the PTX was investigated and no significant difference was found (p=0.472). Using Pneumoscan to detect PTX is controversial since the device has a high false positive ratio. Wherein, false positive diagnosis can cause unjustifiable chest tube insertion. In addition, the device failed to show the size of the PTX, and therefore, it did not aid in determining the treatment and prognosis on contrary to traditional diagnostic methods. The findings could not demonstrate that the device was efficient in emergency care. Further studies and increasing experience may change this outcome in upcoming years.
Singh, Gurmukh
2017-01-01
Background Serum free light chain assay (SFLCA) and κ/λ ratio, and protein electrophoretic methods are used in the diagnosis and monitoring of monoclonal gammopathies. Methods Results for serum free light chains, serum and urine protein electrophoreses and immunofixation electrophoreses in 468 patients with a diagnosis of monoclonal gammopathy were compared. The results of the two methods were graded as concordant, non-concordant or discordant with the established diagnoses to assess the relative performance of the methods. Results of κ/λ ratio in samples with monoclonal protein detectable by electrophoretic methods were also analyzed. Results Protein electrophoreses results were concordant with the established diagnoses significantly more often than κ/λ ratio. The false negative rate for κ/λ ratio was higher than that for electrophoretic methods. κ/λ ratio was falsely negative in about 27% of the 1,860 samples with detectable monoclonal immunoglobulin. The false negative rate was higher in lesions with lambda chains (32%) than those with kappa chains (24%). The false negative rate for κ/λ ratio was over 55% in samples with monoclonal gammopathy of undetermined significance. Even at first encounter, the false negative rates for κ/λ ratios for monoclonal gammopathy of undetermined significance, smoldering myeloma and multiple myeloma were 66.98%, 23.08%, and 30.15%, respectively, with false negative rate for lambda chain lesions being higher. Conclusions Electrophoretic studies of serum and urine are superior to SFLCA and κ/λ ratio. Abnormal κ/λ ratio, per se, is not diagnostic of monoclonal gammopathy. A normal κ/λ ratio does not exclude monoclonal gammopathy. False negative rates for lesions with lambda chain are higher than those for lesions with kappa chains. Electrophoretic studies of urine are underutilized. Clinical usefulness and medical necessity of SFLCA and κ/λ ratio is of questionable value in routine clinical testing. PMID:27924175
Singh, Gurmukh
2017-01-01
Serum free light chain assay (SFLCA) and κ/λ ratio, and protein electrophoretic methods are used in the diagnosis and monitoring of monoclonal gammopathies. Results for serum free light chains, serum and urine protein electrophoreses and immunofixation electrophoreses in 468 patients with a diagnosis of monoclonal gammopathy were compared. The results of the two methods were graded as concordant, non-concordant or discordant with the established diagnoses to assess the relative performance of the methods. Results of κ/λ ratio in samples with monoclonal protein detectable by electrophoretic methods were also analyzed. Protein electrophoreses results were concordant with the established diagnoses significantly more often than κ/λ ratio. The false negative rate for κ/λ ratio was higher than that for electrophoretic methods. κ/λ ratio was falsely negative in about 27% of the 1,860 samples with detectable monoclonal immunoglobulin. The false negative rate was higher in lesions with lambda chains (32%) than those with kappa chains (24%). The false negative rate for κ/λ ratio was over 55% in samples with monoclonal gammopathy of undetermined significance. Even at first encounter, the false negative rates for κ/λ ratios for monoclonal gammopathy of undetermined significance, smoldering myeloma and multiple myeloma were 66.98%, 23.08%, and 30.15%, respectively, with false negative rate for lambda chain lesions being higher. Electrophoretic studies of serum and urine are superior to SFLCA and κ/λ ratio. Abnormal κ/λ ratio, per se , is not diagnostic of monoclonal gammopathy. A normal κ/λ ratio does not exclude monoclonal gammopathy. False negative rates for lesions with lambda chain are higher than those for lesions with kappa chains. Electrophoretic studies of urine are underutilized. Clinical usefulness and medical necessity of SFLCA and κ/λ ratio is of questionable value in routine clinical testing.
Causes of false-negative for high-grade urothelial carcinoma in urine cytology.
Lee, Paul J; Owens, Christopher L; Lithgow, Marie Y; Jiang, Zhong; Fischer, Andrew H
2016-12-01
The Paris System for classifying urine cytology emphasizes identification of high-grade urothelial carcinoma (HGUC). The causes of false-negative urine cytologies (UC) within this system are not well described. We identified 660 cases between 2005 and 2013 with both UC and subsequent cystoscopic biopsies. UC were classified as either Negative for HGUC or "Abnormal" ("Atypical", "Suspicious", and "Malignant"). Apparent false-negative cases were reviewed in a nonblinded fashion by two cytopathologists and two subspecialized genitourinary pathologists. A total of 199 of the 660 cases (30%) were histologically diagnosed as HGUC. The UC were "Abnormal" in 170/199 cases (sensitivity/specificity of 86%/71%). Twenty four apparent false negative cases were available for retrospective review. Five of 24 (21%) cystoscopic biopsies were found not to be HGUC on review (one false positive and four low-grade urothelial carcinoma (LGUC on review). Of the remaining 19 UC, 7 (29%) cytology samples were found to be truly negative on review, 11 (46%) were found to be Atypical, and 1 (4%) suspicious. Of the 12 UC that were at least "Atypical" with histologic HGUC on review: six misses (half) were attributed to obscuring inflammation/blood, four to poor preservation, eight to paucity of abnormal cells, and 1 case to interpretive error; many cases demonstrated overlapping reasons. About one fifth of apparent false negative diagnoses for HGUC can be because of overdiagnosis of HGUC by surgical pathologists. If poor preservation or obscured samples are called nondiagnostic, the sensitivity/specificity of UC for HGUC can be as high as 94%/71%. Diagn. Cytopathol. 2016;44:994-999. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Microscopic diagnosis of dysbacteriosis in stained vaginal smears in clinical practice.
Verbruggen, Banut-Sabine M; Boon, Mathilde E; Melkerl, Peter; van Haaften, Maarten; Heintz, A Peter M
2006-10-01
Dysbacteriosis is a microscopical diagnosis. In women with dysbacteriosis, an overgrowth of coccoid bacteria and almost a complete absence of lactobacilli are observed in the (stained) vaginal smear. The aim of this study was to determine the accuracy of this microscopic diagnosis in clinical practice. The analysis concerned 342 consecutive cases in which the microscopy of the stained smears was performed by general practitioners trained in diagnosing dysbacteriosis. These smears were sent to the pathologist for confirmation of the microscopical diagnosis of the clinician. The cytological diagnoses of the pathologist, sometimes performed on restained slides when the quality of the staining was substandard, were considered as the "gold standard." In 92 of the 342 cases, dysbacteriosis was unequivocally established by the pathologist. Sensitivity and specificity of the microscopical diagnoses of the clinicians were 40% and 85%, respectively. There were 37 false-positive and 54 false-negative diagnoses of dysbacteriosis rendered by the clinicians. The most frequent reason for a false-negative diagnosis was an excess of lactobacilli in the smear. This study shows that even in stained smears it is difficult for clinicians to render a correct evaluation of the status of the vaginal flora.
Almawazini, Abdulmajid M; Hanafi, Hamdi K; Madkhali, Hasan A; Majrashi, Noura B
2017-10-01
To evaluate the effectiveness of critical congenital heart disease (CCHD) screening program for early diagnosis of cardiac anomalies in newborn infants. Methods: This is a hospital-based prospective cross-sectional study conducted in the Pediatric and Neonatology Department, King Fahad Hospital at Albaha, Saudi Arabia, between February 2016 and February 2017. Results: We screened 2961 (95.4%) of 3103 patients in a nursery unit; 142 (4.6%) patients were not screened. The test was positive in 114 (3.9%) patients and negative in 2847 (96.1%). There were 94 (3.2%) false positives and 20 (0.7%) true positives. Critical cardiac defects were diagnosed in 7 (0.2%) patients of all screened infants, and severe pulmonary hypertension was diagnosed in 13 (0.4%) patients. True negative results were found in 2841(96%) patients, and no cardiac defect was diagnosed, whereas false negative results were seen in 6 (0.2%) patients diagnosed with ventricular septal defect. The sensitivity was 77%, and the specificity was very high at 97%, with a positive predictive value of 18%, and a negative predictive value of 99.8% (95% confidence interval 13.78-19.18, p=0.0001). Conclusion: Pulse oximetry was found to be easy, safe, sensitive, and highly specific for diagnosis of CCHD.
Yamatsuji, Tomoki; Ishida, Naomasa; Takaoka, Munenori; Hayashi, Jiro; Yoshida, Kazuhiro; Shigemitsu, Kaori; Urakami, Atsushi; Haisa, Minoru; Naomoto, Yoshio
2017-01-01
Of 129 esophagectomies at our institute from June 2010 to March 2015, we experienced three preoperative positron emission tomography-computed tomographic (PET/CT) false positives. Bone metastasis was originally suspected in 2 cases, but they were later found to be bone metastasis negative after a preoperative bone biopsy and clinical course observation. The other cases suspected of mediastinal lymph node metastasis were diagnosed as inflammatory lymphadenopathy by a pathological examination of the removed lymph nodes. Conducting a PET/CT is useful when diagnosing esophageal cancer metastasis, but we need to be aware of the possibility of false positives. Therapeutic decisions should be made based on appropriate and accurate diagnoses, with pathological diagnosis actively introduced if necessary. PMID:28469502
Rossi, Esther Diana; Wong, Lawrence Q; Bizzarro, Tommaso; Petrone, Gianluigi; Mule, Antonio; Fadda, Guido; Baloch, Zubair M
2016-06-01
Fine-needle aspiration cytology (FNAC) has proven its value as an essential step in the diagnosis of salivary gland lesions. Although the majority of salivary gland lesions, especially those that are common and benign, can be diagnosed with ease on FNAC, limited cellularity and morphologic lesion heterogeneity can pose diagnostic challenges and lead to false-positive and false-negative diagnoses. This study presents the institutional experience of FNAC of salivary gland lesions from 2 academic centers. A retrospective analysis was conducted on 1729 salivary gland FNAC specimens that were diagnosed over an 8-year period from January 2008 to March 2015. All samples were processed either with liquid-based cytology alone or in combination with air-dried, Diff-Quik-stained or alcohol-fixed, Papanicolaou-stained smears. Surgical excision was performed in 709 of 1749 FNACs (41%) that were diagnosed as nondiagnostic/inadequate (n = 29), benign (n = 111), neoplasm (n = 453), atypical (n = 15), suspicious for malignancy (n = 28), and malignant (n = 73). The overall concordance between cytologic and histologic diagnoses was 92.2%, with 91.8% concordance in the benign category and 89.5% concordance in cases diagnosed as suspicious for malignancy and malignant. The most frequent benign and malignant lesions were pleomorphic adenoma and squamous cell carcinoma, respectively. There were 46 false-negative and 13 false-positive results, leading to an overall specificity of 97.6% and diagnostic accuracy of 91.3%. FNAC is a reliable diagnostic modality for the diagnosis and management of salivary gland lesions based on its high specificity and diagnostic accuracy. Cancer Cytopathol 2016;124:388-96. © 2016 American Cancer Society. © 2016 American Cancer Society.
Accuracy in inference of nursing diagnoses in heart failure patients.
Pereira, Juliana de Melo Vellozo; Cavalcanti, Ana Carla Dantas; Lopes, Marcos Venícios de Oliveira; da Silva, Valéria Gonçalves; de Souza, Rosana Oliveira; Gonçalves, Ludmila Cuzatis
2015-01-01
Heart failure (HF) is a common cause of hospitalization and requires accuracy in clinical judgment and appropriate nursing diagnoses. to determine the accuracy of nursing diagnoses of fatigue, intolerance to activity and decreased cardiac output in hospitalized HF patients. descriptive study applied to nurses with experience in NANDA-I and/or HF nursing diagnoses. Evaluation and accuracy were determined by calculating efficacy (E), false negative (FN), false positive (FP) and trend (T) measures. Nurses who showed acceptable inspection for two diagnoses were selected. the nursing diagnosis of fatigue was the most commonly mistaken diagnosis identified by the nursing evaluators. the search for improving diagnostic accuracy reaffirms the need for continuous and specific training to improve the diagnosis capability of nurses. the training allowed the exercise of clinical judgment and better accuracy of nurses.
Ko, Kyung Dae; El-Ghazawi, Tarek; Kim, Dongkyu; Morizono, Hiroki
2014-05-01
Motor neuron diseases (MNDs) are a class of progressive neurological diseases that damage the motor neurons. An accurate diagnosis is important for the treatment of patients with MNDs because there is no standard cure for the MNDs. However, the rates of false positive and false negative diagnoses are still very high in this class of diseases. In the case of Amyotrophic Lateral Sclerosis (ALS), current estimates indicate 10% of diagnoses are false-positives, while 44% appear to be false negatives. In this study, we developed a new methodology to profile specific medical information from patient medical records for predicting the progression of motor neuron diseases. We implemented a system using Hbase and the Random forest classifier of Apache Mahout to profile medical records provided by the Pooled Resource Open-Access ALS Clinical Trials Database (PRO-ACT) site, and we achieved 66% accuracy in the prediction of ALS progress.
False Negatives, Canter's Background Interference Procedure, the Trail Making Test, and Epileptics.
ERIC Educational Resources Information Center
McKinzey, Ronald K.; And Others
1985-01-01
Results of correlation studies of 141 adult epileptics' scores on the Background Interference Procedure (BIP) indicated that the BIP often does not agree with abnormal neurological diagnoses but often does agree with psychiatric diagnoses of Organic Brain Syndrome (OBS). Suggests that future BIP validity studies include a behavioral measure of OBS…
Parry, John V; Easterbrook, Philippa; Sands, Anita R
2017-11-01
Initial serological testing for chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection is conducted using either rapid diagnostic tests (RDT) or laboratory-based enzyme immunoassays (EIA)s for detection of hepatitis B surface antigen (HBsAg) or antibodies to HCV (anti-HCV), typically on serum or plasma specimens and, for certain RDTs, capillary whole blood. WHO recommends the use of standardized testing strategies - defined as a sequence of one or more assays to maximize testing accuracy while simplifying the testing process and ideally minimizing cost. Our objective was to examine the diagnostic outcomes of a one- versus two-assay serological testing strategy. These data were used to inform recommendations in the 2017 WHO Guidelines on hepatitis B and C testing. Few published studies have compared diagnostic outcomes for one-assay versus two-assay serological testing strategies for HBsAg and anti-HCV. Therefore, the principles of Bayesian statistics were used to conduct a modelling exercise to examine the outcomes of a one-assay versus two-assay testing strategy when applied to a hypothetical population of 10,000 individuals. The resulting model examined the diagnostic outcomes (true and false positive diagnoses; true and false negative diagnoses; positive and negative predictive values as a function of prevalence; and total tests required) for both one-assay and two-assay testing strategies. The performance characteristics assumed for assays used within the testing strategies were informed by WHO prequalification assessment findings and systematic reviews for diagnostic accuracy studies. Each of the presumptive testing strategies (one-assay or two-assay) was modelled at varying prevalences of HBsAg (10%, 2% and 0.4%) and of anti-HCV (40%, 10%, 2% and 0.4%), aimed at representing the range of testing populations typically encountered in WHO Member States. When the two-assay testing strategy was considered, the model assumed the independence of the two assays. Modeling demonstrated that applying a single assay (HBsAg or anti-HCV), even with high specificity (99%), may result in considerable numbers of false positive diagnoses and low positive predictive values (PPV), particularly in lower prevalence settings. Even at very low prevalences shifting to a two-assay testing strategy would result in a PPV approaching 1.0. When test sensitivity is high (>99%) false negative reactions are rare at all but the highest prevalences; but a two-test strategy might yield more false negative diagnoses. The order in which the tests are used has no impact on the overall accuracy of a two-assay strategy though it may impact the total number of tests needed to complete the diagnostic strategy, incurring added cost and complexity. HBsAg assays may have a low sensitivity (<90%), and result in large numbers of false negative diagnoses, particularly in high prevalence settings, which would be exacerbated in the two-assay testing strategy. In contrast, most anti-HCV assays have high sensitivity and lead to fewer false negative results, both in the one-assay and two-assay testing strategies. At prevalences ≤2% the number of tests needed using a second assay was nearly always small, at <300 per 10,000 individuals tested, making sustainability of a second assay uncertain in such a setting. A key public health objective of an effective testing strategy is to identify all individuals who would benefit from treatment. Therefore, a strategy that prioritizes a high NPV (minimal false negatives) may be acceptable even if the PPV is suboptimal (some false positives) as the implementation of such a public health programme must also take account of other factors such as costs, feasibility, impact on testing uptake and linkage to care, and consequences of a false-positive test. This rationale informed the development of the WHO Viral Hepatitis Testing Guidelines, with a conditional recommendation for a one-assay serological testing strategy in most testing settings and populations (≥0.4% prevalence in population tested). A one-test strategy results in few failures to diagnose infection and, although it is associated under most assumptions with a sub-optimal PPV, benefits include greater simplicity, easier implementation, lower costs and better feasibility, uptake and linkage to care. Furthermore, prior to antiviral therapy all those diagnosed either HBsAg or anti-HCV positive will require confirmation of viræmia, preventing unnecessary treatment of those who may be false positive on serology. For HBsAg, in low-prevalence settings (≤0.4%), a second recommendation was made to consider a two-assay testing strategy, using a confirmatory neutralization step or a second different HBsAg assay.
Sadder and less accurate? False memory for negative material in depression.
Joormann, Jutta; Teachman, Bethany A; Gotlib, Ian H
2009-05-01
Previous research has demonstrated that induced sad mood is associated with increased accuracy of recall in certain memory tasks; the effects of clinical depression, however, are likely to be quite different. The authors used the Deese-Roediger-McDermott paradigm to examine the impact of clinical depression on erroneous recall of neutral and/or emotional stimuli. Specifically, they presented Deese-Roediger-McDermott lists that were highly associated with negative, neutral, or positive lures and compared participants diagnosed with major depressive disorder and nondepressed control participants on the accuracy of their recall of presented material and their false recall of never-presented lures. Compared with control participants, major depressive disorder participants recalled fewer words that had been previously presented but were more likely to falsely recall negative lures; there were no differences between major depressive disorder and control participants in false recall of positive or neutral lures. These findings indicate that depression is associated with false memories of negative material.
Iguchi, Hiroyoshi; Wada, Tadashi; Matsushita, Naoki; Oishi, Masahiro; Teranishi, Yuichi; Yamane, Hideo
2014-07-01
The accuracy and sensitivity of fine-needle aspiration cytology (FNAC) in this analysis were not satisfactory, and the false-negative rate seemed to be higher than for parotid tumours. The possibility of low-grade malignancy should be considered in the surgical treatment of accessory parotid gland (APG) tumours, even if the preoperative results of FNAC suggest that the tumour is benign. Little is known about the usefulness of FNAC in the preoperative evaluation of APG tumours, probably due to the paucity of APG tumour cases. We examined the usefulness of FNAC in the detection of malignant APG tumours. We conducted a retrospective analysis of 3 cases from our hospital, along with 18 previously reported Japanese cases. We compared the preoperative FNAC results with postoperative histopathological diagnoses of APG tumours and evaluated the accuracy, sensitivity, specificity and false-negative rates of FNAC in detecting malignant APG tumours. There were four false-negative cases (19.0%), three of mucoepidermoid carcinomas and one of malignant lymphoma. One false-positive result was noted in the case of a myoepithelioma, which was cytologically diagnosed as suspected adenoid cystic carcinoma. The accuracy, sensitivity and specificity of FNAC in detecting malignant tumours were 76.2%, 60.0% and 90.9%, respectively.
Breast cancers not detected at MRI: review of false-negative lesions.
Shimauchi, Akiko; Jansen, Sanaz A; Abe, Hiroyuki; Jaskowiak, Nora; Schmidt, Robert A; Newstead, Gillian M
2010-06-01
The objective of our study was to determine the sensitivity of cancer detection at breast MRI using current imaging techniques and to evaluate the characteristics of lesions with false-negative examinations. Two hundred seventeen patients with 222 newly diagnosed breast cancers or highly suspicious breast lesions that were subsequently shown to be malignant underwent breast MRI examinations for staging. Two breast imaging radiologists performed a consensus review of the breast MRI examinations. The absence of perceptible contrast enhancement at the expected site was considered to be a false-negative MRI. Histology of all lesions was reviewed by an experienced breast pathologist. Enhancement was observed in 213 (95.9%) of the 222 cancer lesions. Of the nine lesions without visible enhancement, two lesions were excluded because the entire tumor had been excised at percutaneous biopsy performed before the MRI examination and no residual tumor was noted on the final histology. The overall sensitivity of MRI for the known cancers was 96.8% (213/220); for invasive cancer, 98.3% (176/179); and for ductal carcinoma in situ, 90.2% (37/41). In a population of 220 sequentially diagnosed breast cancer lesions, we found seven (3.2%) MRI-occult cancers, fewer than seen in other published studies. Small tumor size and diffuse parenchymal enhancement were the principal reasons for these false-negative results. Although the overall sensitivity of cancer detection was high (96.8%), it should be emphasized that a negative MRI should not influence the management of a lesion that appears to be of concern on physical examination or on other imaging techniques.
Bonanzinga, Tommaso; Zahar, Akos; Dütsch, Michael; Lausmann, Christian; Kendoff, Daniel; Gehrke, Thorsten
2017-02-01
A key issue in the treatment of periprosthetic joint infection (PJI) is the correct diagnosis. The main problem is lack of diagnostic tools able to diagnose a PJI with high accuracy. Alpha-defensin has been proposed as a possible solution, but in the current literature, there is a lack of independent validation. We performed a prospective study to determine (1) what is the sensitivity, specificity, and positive and the negative predictive values of the alpha-defensin immunoassay test in diagnosing PJI; and (2) which clinical features may be responsible for false-positive and false-negative results? Preoperative aspiration was performed in all patients presenting with a painful hip/knee arthroplasty, including both primary and revision implants. Metallosis, other inflammatory comorbidities, and previous/concomitant antibiotic therapy were not considered as exclusion criteria. An inadequate amount of synovial fluid for culture was an exclusion criterion. A total of 156 patients (65 knees, 91 hips) were included in this prospective study. At the time of revision, synovial fluid samples were taken to perform the alpha-defensin assay. During surgical débridement of tissue, samples for cultures and histologic evaluation were taken, and samples were cultured until positive or until negative at 14 days. A diagnosis of PJI was confirmed in 29 patients according to the International Consensus Group on PJI. The sensitivity of the alpha-defensin immunoassay was 97% (95% confidence interval [CI], 92%-99%), the specificity was 97% (95% CI, 92%-99%), the positive predictive value was 88% (95% CI, 81%-92%), and the negative predictive value was 99% (95% CI, 96%-99%). Among four false-positive patients, two had metallosis and one had polyethylene wear. The false-negative case presented with a draining sinus, and intraoperative cultures were also negative. Alpha-defensin assay appears to be a reliable test, but followup evaluation is needed to estimate longer term performance of the test. The authors believe that alpha-defensin has demonstrated itself to be sufficiently robust that PJI diagnostic criteria now should include this test. Future studies are needed to compare the differences among the diagnostic capability of the available tests, in particular when metallosis is present, because metallosis may predispose the test to a false-positive result. Level I, diagnostic study.
Weemhoff, M; Kluivers, K B; Govaert, B; Evers, J L H; Kessels, A G H; Baeten, C G
2013-03-01
This study concerns the level of agreement between transperineal ultrasound and evacuation proctography for diagnosing enteroceles and intussusceptions. In a prospective observational study, 50 consecutive women who were planned to have an evacuation proctography underwent transperineal ultrasound too. Sensitivity, specificity, positive (PPV) and negative predictive value, as well as the positive and negative likelihood ratio of transperineal ultrasound were assessed in comparison to evacuation proctography. To determine the interobserver agreement of transperineal ultrasound, the quadratic weighted kappa was calculated. Furthermore, receiver operating characteristic curves were generated to show the diagnostic capability of transperineal ultrasound. For diagnosing intussusceptions (PPV 1.00), a positive finding on transperineal ultrasound was predictive of an abnormal evacuation proctography. Sensitivity of transperineal ultrasound was poor for intussusceptions (0.25). For diagnosing enteroceles, the positive likelihood ratio was 2.10 and the negative likelihood ratio, 0.85. There are many false-positive findings of enteroceles on ultrasonography (PPV 0.29). The interobserver agreement of the two ultrasonographers assessed as the quadratic weighted kappa of diagnosing enteroceles was 0.44 and that of diagnosing intussusceptions was 0.23. An intussusception on ultrasound is predictive of an abnormal evacuation proctography. For diagnosing enteroceles, the diagnostic quality of transperineal ultrasound was limited compared to evacuation proctography.
Gupta, Nalini; Banik, Tarak; Rajwanshi, Arvind; Radotra, Bishan D; Panda, Naresh; Dey, Pranab; Srinivasan, Radhika; Nijhawan, Raje
2012-01-01
This study was undertaken to evaluate the diagnostic utility and pitfalls of fine needle aspiration cytology (FNAC) in oral and oropharyngeal lesions. This was a retrospective audit of oral and oropharyngeal lesions diagnosed with FNAC over a period of six years (2005-2010). Oral/oropharyngeal lesions [n=157] comprised 0.35% of the total FNAC load. The age ranged 1-80 years with the male: female ratio being 1.4:1. Aspirates were inadequate in 7% cases. Histopathology was available in 73/157 (46.5%) cases. Palate was the most common site of involvement [n=66] followed by tongue [n=35], buccal mucosa [n=18], floor of the mouth [n=17], tonsil [n=10], alveolus [n=5], retromolar trigone [n=3], and posterior pharyngeal wall [n=3]. Cytodiagnoses were categorized into infective/inflammatory lesions and benign cysts, and benign and malignant tumours. Uncommon lesions included ectopic lingual thyroid and adult rhabdomyoma of tongue, and solitary fibrous tumor (SFT), and leiomyosarcoma in buccal mucosa. A single false-positive case was dense inflammation with squamous cells misinterpreted as squamous cell carcinoma (SCC) on cytology. There were eight false-negative cases mainly due to sampling error. One false-negative case due to interpretation error was in a salivary gland tumor. The sensitivity of FNAC in diagnosing oral/oropharyngeal lesions was 71.4%; specificity was 97.8% with diagnostic accuracy of 87.7%. Salivary gland tumors and squamous cell carcinoma (SCC) are the most common lesions seen in the oral cavity. FNAC proves to be highly effective in diagnosing the spectrum of different lesions in this region. Sampling error is the main cause of false-negative cases in this region.
Kwon, Hyuk-Jin; Yoo, Hee-Jeong; Kim, Joo-Hyun; Noh, Dong-Hyun; Sunwoo, Hyun-Jung; Jeon, Ye Seul; Lee, Sang-Youn; Jo, Ye-Ul; Bong, Gui-Young
2017-10-01
The current cut-off score of the Korean version of the Childhood Autism Rating Scale (K-CARS) does not seem to be sensitive enough to precisely diagnose high-functioning autism. The aim of this study was to identify the optimal cut-off score of K-CARS for diagnosing high-functioning individuals with autism spectrum disorders (ASD). A total of 329 participants were assessed by the Korean versions of the Autism Diagnostic Interview - Revised (K-ADI-R), Autism Diagnostic Observation Schedule (K-ADOS), and K-CARS. IQ and Social Maturity Scale scores were also obtained. The true positive and false negative rates of K-CARS were 77.2% and 22.8%, respectively. Verbal IQ (VIQ) and Social Quotient (SQ) were significant predictors of misclassification. The false negative rate increased to 36.0% from 19.8% when VIQ was >69.5, and the rate increased to 44.1% for participants with VIQ > 69.5 and SQ > 75.5. In addition, if SQ was >83.5, the false negative rate increased to 46.7%, even if the participant's VIQ was ≤69.5. Optimal cut-off scores were 28.5 (for VIQ ≤ 69.5 and SQ ≤ 75.5), 24.25 (for VIQ > 69.5 and SQ > 75.5), and 24.5 (for SQ > 83.5), respectively. The likelihood of a false negative error increases when K-CARS is used to diagnose high-functioning autism and Asperger's syndrome. For subjects with ASD and substantial verbal ability, the cut-off score for K-CARS should be re-adjusted and/or supplementary diagnostic tools might be needed to enhance diagnostic accuracy for ASD. © 2017 The Authors. Psychiatry and Clinical Neurosciences © 2017 Japanese Society of Psychiatry and Neurology.
Dalquen, P; Rashed, B; Hinsch, A; Issa, R; Clauditz, T; Luebke, A; Lüttges, J; Saeger, W; Bohuslavizki, K H
2016-09-01
Diagnostic problems of thyroid cytology are frequently discussed, but relevance and causes of discrepant cytological and histological diagnoses are rarely studied in detail. Investigation of causes and relevance of discrepant diagnoses. The analysis includes 297 patients who had thyroid resection after prior fine needle aspiration (FNA) and is based on the cytological and histological reports. In special cases, cytological and histological specimens were re-examined. Malignant tumors were found in 45 patients (15.1 %). In 5 patients the cytological diagnosis was "false negative". Three of these 5 tumors were papillary carcinomas (PTC) of ≤10 mm, one an obviously nonmalignant papillary proliferation of the thyroidal epithelium and one a malignant lymphoma complicating autoimmune thyreoiditis (AIT). In 11 of the 35 patients with a FNA diagnosis "suspicious of malignancy" or "malignant," 1 AIT, 4 goiter nodules, and 6 adenomas were diagnosed histologically. However, since distinct nuclear atypia was found in three of five false positive diagnoses, there still remains doubt in their benignity. Carcinomas of ≤10 mm incidentally detected in the resected thyroid tissue may not be relevant to the patient and do not reduce the high negative predictive value of FNA. The final diagnosis on the resected tissue should include the cytological findings. Discrepant findings should be commented in the report to the clinician.
Trinh, Tony W; Glazer, Daniel I; Sadow, Cheryl A; Sahni, V Anik; Geller, Nina L; Silverman, Stuart G
2018-03-01
To determine test characteristics of CT urography for detecting bladder cancer in patients with hematuria and those undergoing surveillance, and to analyze reasons for false-positive and false-negative results. A HIPAA-compliant, IRB-approved retrospective review of reports from 1623 CT urograms between 10/2010 and 12/31/2013 was performed. 710 examinations for hematuria or bladder cancer history were compared to cystoscopy performed within 6 months. Reference standard was surgical pathology or 1-year minimum clinical follow-up. False-positive and false-negative examinations were reviewed to determine reasons for errors. Ninety-five bladder cancers were detected. CT urography accuracy: was 91.5% (650/710), sensitivity 86.3% (82/95), specificity 92.4% (568/615), positive predictive value 63.6% (82/129), and negative predictive value was 97.8% (568/581). Of 43 false positives, the majority of interpretation errors were due to benign prostatic hyperplasia (n = 12), trabeculated bladder (n = 9), and treatment changes (n = 8). Other causes include blood clots, mistaken normal anatomy, infectious/inflammatory changes, or had no cystoscopic correlate. Of 13 false negatives, 11 were due to technique, one to a large urinary residual, one to artifact. There were no errors in perception. CT urography is an accurate test for diagnosing bladder cancer; however, in protocols relying predominantly on excretory phase images, overall sensitivity remains insufficient to obviate cystoscopy. Awareness of bladder cancer mimics may reduce false-positive results. Improvements in CTU technique may reduce false-negative results.
The diagnostic significance of lactate dehydrogenase isoenzymes in urinary cytology.
Nishikawa, A.; Tanaka, T.; Takeuchi, T.; Fujihiro, S.; Mori, H.
1991-01-01
Lactate dehydrogenase (LDH) isoenzyme distribution was examined in 106 urine samples being tested cytologically for evidence of bladder cancer; the samples were selected to have less than 20 leucocytes and erythrocytes per high power field and the LDH pattern determined by electrophoresis. The Papanicolaou stained-smears showed 68 negative, 17 suspicious and 21 positive. The LDH M-fraction of the urinary supernatant in cytologically positive cases was significantly greater than in negative cases, although the latter included a few false negative samples. Some of the false negatives gave positive results for the LDH M-fraction; these results suggest that the determination of LDH isoenzymes in the urine is useful in diagnosing urinary tract cancers, including early stage, and for follow-up of patients with bladder cancers after surgical resection. PMID:2039708
Multidetector computed tomography urography for diagnosing upper urinary tract urothelial tumour.
Cowan, Nigel C; Turney, Ben W; Taylor, Nia J; McCarthy, Catherine L; Crew, Jeremy P
2007-06-01
To evaluate multidetector computed tomography urography (MDCTU) for diagnosing upper urinary tract (UUT) urothelial tumour by comparison with retrograde ureteropyelography (RUP). MDCTU and RUP were used in a selected series of adult patients presenting with haematuria. Entry criteria were based on findings on intravenous urography and were chosen to ensure a high prevalence of UUT urothelial tumour to allow a valid retrospective comparison of the diagnostic techniques. MDCTU and RUP studies were scored for the presence and absence of UUT urothelial tumour by two radiologists, retrospectively and independently, and while unaware of the demographic and clinical information. The reference standards were the histopathology and clinical follow-up. MDCTU and RUP were used in 106 patients over a 24-month period. RUP was attempted in 151 of 212 UUTs; the corresponding MDCTU for each UUT was reviewed. MDCTU was a true-positive (TP) for urothelial tumour in 31, true-negative (TN) in 111, false-positive (FP) in eight and false-negative (FN) in one UUT, giving a sensitivity of 0.97, a specificity of 0.93, a positive predictive value (PPV) of 0.79 and a negative PV (NPV) of 0.99. RUP was technically successful and diagnostic in 96% of the UUTs (143/151). For diagnosing urothelial tumour, RUP was TP in 26, TN in 112, FP in four and FN in one UUT, giving a sensitivity of 0.97, specificity of 0.93, a PPV of 0.79 and NPV of 0.99. This study validates quantitatively the use of MDCTU for diagnosing UUT urothelial tumour.
Graff, L; Russell, J; Seashore, J; Tate, J; Elwell, A; Prete, M; Werdmann, M; Maag, R; Krivenko, C; Radford, M
2000-11-01
To test the hypothesis that physician errors (failure to diagnose appendicitis at initial evaluation) correlate with adverse outcome. The authors also postulated that physician errors would correlate with delays in surgery, delays in surgery would correlate with adverse outcomes, and physician errors would occur on patients with atypical presentations. This was a retrospective two-arm observational cohort study at 12 acute care hospitals: 1) consecutive patients who had an appendectomy for appendicitis and 2) consecutive emergency department abdominal pain patients. Outcome measures were adverse events (perforation, abscess) and physician diagnostic performance (false-positive decisions, false-negative decisions). The appendectomy arm of the study included 1, 026 patients with 110 (10.5%) false-positive decisions (range by hospital 4.7% to 19.5%). Of the 916 patients with appendicitis, 170 (18.6%) false-negative decisions were made (range by hospital 10.6% to 27.8%). Patients who had false-negative decisions had increased risks of perforation (r = 0.59, p = 0.058) and of abscess formation (r = 0.81, p = 0.002). For admitted patients, when the inhospital delay before surgery was >20 hours, the risk of perforation was increased [2.9 odds ratio (OR) 95% CI = 1.8 to 4.8]. The amount of delay from initial physician evaluation until surgery varied with physician diagnostic performance: 7.0 hours (95% CI = 6.7 to 7.4) if the initial physician made the diagnosis, 72.4 hours (95% CI = 51.2 to 93.7) if the initial office physician missed the diagnosis, and 63.1 hours (95% CI = 47.9 to 78.4) if the initial emergency physician missed the diagnosis. Patients whose diagnosis was initially missed by the physician had fewer signs and symptoms of appendicitis than patients whose diagnosis was made initially [appendicitis score 2.0 (95% CI = 1.6 to 2.3) vs 6.5 (95% CI = 6.4 to 6.7)]. Older patients (>41 years old) had more false-negative decisions and a higher risk of perforation or abscess (3.5 OR 95% CI = 2.4 to 5.1). False-positive decisions were made for patients who had signs and symptoms similar to those of appendicitis patients [appendicitis score 5.7 (95% CI = 5.2 to 6.1) vs 6.5 (95% CI = 6.4 to 6.7)]. Female patients had an increased risk of false-positive surgery (2.3 OR 95% CI = 1.5 to 3.4). The abdominal pain arm of the study included 1,118 consecutive patients submitted by eight hospitals, with 44 patients having appendicitis. Hospitals with observation units compared with hospitals without observation units had a higher "rule out appendicitis" evaluation rate [33.7% (95% CI = 27 to 38) vs 24.7% (95% CI = 23 to 27)] and a similar hospital admission rate (27.6% vs 24.7%, p = NS). There was a lower miss-diagnosis rate (15.1% vs 19.4%, p = NS power 0.02), lower perforation rate (19.0% vs 20.6%, p = NS power 0.05), and lower abscess rate (5.6% vs 6.9%, p = NS power 0.06), but these did not reach statistical significance. Errors in physician diagnostic decisions correlated with patient clinical findings, i.e., the missed diagnoses were on appendicitis patients with few clinical findings and unnecessary surgeries were on non-appendicitis patients with clinical findings similar to those of patients with appendicitis. Adverse events (perforation, abscess formation) correlated with physician false-negative decisions.
Cost-effectiveness of WHO-Recommended Algorithms for TB Case Finding at Ethiopian HIV Clinics.
Adelman, Max W; McFarland, Deborah A; Tsegaye, Mulugeta; Aseffa, Abraham; Kempker, Russell R; Blumberg, Henry M
2018-01-01
The World Health Organization (WHO) recommends active tuberculosis (TB) case finding and a rapid molecular diagnostic test (Xpert MTB/RIF) to detect TB among people living with HIV (PLHIV) in high-burden settings. Information on the cost-effectiveness of these recommended strategies is crucial for their implementation. We conducted a model-based cost-effectiveness analysis comparing 2 algorithms for TB screening and diagnosis at Ethiopian HIV clinics: (1) WHO-recommended symptom screen combined with Xpert for PLHIV with a positive symptom screen and (2) current recommended practice algorithm (CRPA; based on symptom screening, smear microscopy, and clinical TB diagnosis). Our primary outcome was US$ per disability-adjusted life-year (DALY) averted. Secondary outcomes were additional true-positive diagnoses, and false-negative and false-positive diagnoses averted. Compared with CRPA, combining a WHO-recommended symptom screen with Xpert was highly cost-effective (incremental cost of $5 per DALY averted). Among a cohort of 15 000 PLHIV with a TB prevalence of 6% (900 TB cases), this algorithm detected 8 more true-positive cases than CRPA, and averted 2045 false-positive and 8 false-negative diagnoses compared with CRPA. The WHO-recommended algorithm was marginally costlier ($240 000) than CRPA ($239 000). In sensitivity analysis, the symptom screen/Xpert algorithm was dominated at low Xpert sensitivity (66%). In this model-based analysis, combining a WHO-recommended symptom screen with Xpert for TB diagnosis among PLHIV was highly cost-effective ($5 per DALY averted) and more sensitive than CRPA in a high-burden, resource-limited setting.
Gestational Trophoblastic Disease Diagnosis Delayed by the Hook Effect.
Cormano, Julia; Mackay, Gillian; Holschneider, Christine
2015-10-01
A "hook effect" resulting from saturation of antibodies used in pregnancy tests can occur at human chorionic gonadotropin (hCG) levels above 500,000 milliinternational units/mL, resulting in falsely negative values. A 34-year-old woman, gravida 5 para 3, presented to the emergency department after heavy bleeding. Ultrasonogram revealed a uterine mass, urine pregnancy test result was negative, and endometrial biopsy inconclusive. The patient was discharged and presented 10 days later with recurrent bleeding. Urine pregnancy test result was again negative, but serum hCG was 581 milliinternational units/mL. Serial dilution revealed an actual hCG higher than 5 million milliinternational units/mL. She was diagnosed with gestational trophoblastic disease. Awareness of the risk of a false-negative pregnancy test result when hCG levels are extremely high may prevent delayed diagnosis of gestational trophoblastic disease.
The role of ultrasound in the management and diagnosis of infectious mononucleosis
2014-01-01
Currently, infectious mononucleosis (IM) is a clinically diagnosed condition. According to the American Family Physician criteria for IM, splenomegaly is the key factor that distinguishes IM from other causes of sore throat. Though heterophile antibody tests are often ordered to confirm diagnosis of IM, this test has a high false-negative rate early in the course of the disease. This case report provides an example of how the use of ultrasound to diagnose splenomegaly and subsequently mononucleosis increases diagnostic accuracy. PMID:24580968
Comparison of the diuretic renogram and the pressure perfusion study in children
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kass, E.J.; Majd, M.; Belman, A.B.
1985-07-01
The authors evaluated 42 hydronephrotic kidneys with diuretic renography and pressure perfusion studies to diagnose or exclude the presence of obstruction. Both studies were highly accurate but a small number of false positive and false negative studies were observed with each testing modality. The advantages, disadvantages and potential sources of inaccuracy of each study are discussed, and a protocol for the evaluation of hydronephrosis incorporating both studies is proposed.
Rossi, E D; Martini, M; Straccia, P; Bizzarro, T; Fadda, G; Larocca, L M
2016-02-01
Our aim was to evaluate the feasibility and diagnostic accuracy of liquid-based cytology (LBC) on lymph node fine needle aspiration (FNA). FNA may fulfil a challenging role in the evaluation of the majority of primary (benign and malignant) diagnoses as well as metastatic lymph node lesions. Although the morphological features may be quite easily recognized, cytological samples with a scant cellular component may raise some issues. We appraised 263 cytological lymph nodes from different body regions analysed between January and December 2013, including 137 male and 126 female patients, and processed with LBC. The cytological diagnoses included 160 benign and 103 malignant lesions. We reported 35 benign and 73 malignant lesions from 108 with surgical follow-up. The latter malignant series included 68 metastatic lesions, four suspicious for malignancy and one inadequate sample. The cytological diagnoses were supported by 62 conclusive immunocytochemical and 28 molecular analyses. Of the 108 cases, we documented 35 true negatives, 72 true positives, one false negative and no false positives, resulting in 98.6% sensitivity, 100% specificity, 99% diagnostic accuracy, 97.2% negative predictive value and 100% positive predictive value. FNA represents the first diagnostic tool in lymph node management and a reliable approach in order to avoid an excision biopsy. Furthermore, LBC is a feasible method for ancillary tests for which methanol-fixed samples are suitable, such as immunocytochemistry and molecular analysis. © 2014 John Wiley & Sons Ltd.
Layfield, Eleanor M; Schmidt, Robert L; Esebua, Magda; Layfield, Lester J
2018-06-01
Frozen section is routinely used for intraoperative margin evaluation in carcinomas of the head and neck. We studied a series of frozen sections performed for margin status of head and neck tumors to determine diagnostic accuracy. All frozen sections for margin control of squamous carcinomas of the head and neck were studied from a 66 month period. Frozen and permanent section diagnoses were classified as negative or malignant. Correlation of diagnoses was performed to determine accuracy. One thousand seven hundred and ninety-six pairs of frozen section and corresponding permanent section diagnoses were obtained. Discordances were found in 55 (3.1%) pairs. In 35 pairs (1.9%), frozen section was reported as benign, but permanent sections disclosed carcinoma. In 21 cases, the discrepancy was due to sampling and in the remaining cases it was an interpretive error. In 20 cases (1.1%), frozen section was malignant, but the permanent section was interpreted as negative. Frozen section is an accurate method for evaluation of operative margins for head and neck carcinomas with concordance between frozen and permanent results of 97%. Most errors are false negative results with the majority of these being due to sampling issues.
Moellering, Douglas R.
2014-01-01
Abstract Background: Glycated hemoglobin (HbA1c) has been advocated for the diagnosis of diabetes and prediabetes. Its performance has been commonly assessed in corroboration with elevated fasting plasma glucose (FPG), but not the combination of FPG and 2-hr glucose values. This study assesses receiver operating characteristics (ROC) curves of HbA1c pertaining to the diagnoses of prediabetes and diabetes by FPG and/or 2-hr glucose, and the effects of age, gender, and race. Methods: We assessed the utility of HbA1c for diagnosing diabetes and prediabetes among 5395 adults without known diabetes from the National Health and Nutrition Examination Survey (NHANES) 2005–2010. Results: Current cutoffs of HbA1c for diabetes (6.5%) or prediabetes (5.7%) exhibited low sensitivity (0.249 and 0.354, respectively) and high specificity in identifying patients diagnosed using both FPG and 2-hr glucose, resulting in large false-negative rates (75.1% and 64.9%). Misdiagnosis rates increased with age and in non-Hispanic whites and Mexican Americans. When HbA1c was combined with FPG for diagnoses, the false-negative rate remained high for diabetes (45.7%), but was reduced for prediabetes (9.2%). Conclusions: When assessed against diagnoses using both FPG and 2-hr glucose, HbA1c had low sensitivity and high specificity for identifying diabetes and prediabetes, which varied as a function of age and race. Regarding recently released American Diabetes Association (ADA) and joint European guidelines, it is important to consider that HbA1c values below 6.5% and 5.7% do not reliably exclude the presence of diabetes and prediabetes, respectively. Overall, the data argue for greater use of oral glucose tolerance tests (OGTTs) and both FPG and 2-hr glucose values for diagnosis of diabetes and prediabetes. PMID:24512556
FDG-PET/CT can rule out malignancy in patients with vocal cord palsy.
Thomassen, Anders; Nielsen, Anne Lerberg; Lauridsen, Jeppe Kiilerich; Blomberg, Björn Alexander; Hess, Søren; Petersen, Henrik; Johansen, Allan; Asmussen, Jon Thor; Sørensen, Jesper Roed; Johansen, Jørgen; Godballe, Christian; Høilund-Carlsen, Poul Flemming
2014-01-01
The aim was to investigate the performance of (18)F-fluorodeoxyglucose PET/CT to rule out malignancy in patients with confirmed vocal cord palsy (VCP). Between January 2011 and June 2013, we retrospectively included consecutive patients referred to PET/CT with paresis or paralysis of one or both vocal cords. PET/CT results were compared to clinical workup and histopathology. The study comprised 65 patients (32 females) with a mean age of 66±12 years (range 37-89). Eleven patients (17%) had antecedent cancer. Twenty-seven (42%) were diagnosed with cancer during follow-up. The palsy was right-sided in 24 patients, left-sided in 37, and bilateral in 4. Median follow-up was 7 months (interquartile range 4-11 months). Patients without cancer were followed for at least three months. PET/CT suggested a malignancy in 35 patients (27 true positives, 8 false positives) and showed none in 30 (30 true negatives, 0 false negatives). Thus, the sensitivity, specificity, positive and negative predictive values, and accuracy were (95% confidence intervals in parenthesis): 100% (88%-100%), 79% (64%-89%), 77% (61%-88%), 100% (89%-100%), and 88% (78%-94%), respectively. Sixteen patients had palliative treatment, while 11 were treated with curative intent, emphasising the severity of VCP and the need for a rapid and accurate diagnostic work-up. In this retrospective survey, biopsy proven malignancy (whether newly diagnosed or relapsed) was the cause of VCP in almost half of patients (42%). PET/CT had a high sensitivity (100%) with a relatively high false positive rate, but was excellent in ruling out malignancy (negative predictive value 100%).
Diagnostic frameworks and nursing diagnoses: a normative stance.
Zanotti, Renzo; Chiffi, Daniele
2015-01-01
Diagnostic frameworks are essential to many scientific and technological activities and clinical practice. This study examines the main fundamental aspects of such frameworks. The three components required for all diagnoses are identified and examined, i.e. their normative dimension, temporal nature and structure, and teleological perspective. The normative dimension of a diagnosis is based on (1) epistemic values when associated with Hempel's inductive risk concerning the balance between false-positive and false-negative outcomes, leading to probabilistic judgements; and (2) non-epistemic values when related to ideas such as well-being, normality, illness, etc, as idealized norms or ideal points of reference. It should be noted that medical diagnoses match the three necessary components, while some essential diagnostic frameworks - the taxonomies of Gordon and NANDA - in nursing lack some components. The main lack is normative as the most popular frameworks in nursing diagnosis seem to be descriptions of observed reality rather than normative and value-based judgements in which both epistemic and non-epistemic values may coexist. © 2014 John Wiley & Sons Ltd.
Nemoto, Kenji; Oh-ishi, Shuji; Taguchi, Masato; Hyodo, Kentaro; Kanazawa, Jun; Miura, Yukiko; Takaku, Takio; Usui, Shingo; Hayashihara, Kenji; Saito, Takefumi
2016-04-01
T-SPOT.TB (T-SPOT), an interferon-gamma release assay, has shown promise as a diagnostic tool for active tuberculosis (TB), and its use is expanding. Addition of the T-Cell Xtend (TCX) reagent may allow delayed processing, and this characteristic is important for using this test in the field. However, limited data is available on the usefulness of T-SPOT with TCX as a field test for diagnosing active TB. To investigate the clinical utility of T-SPOT with TCX and the risk factors for a false-negative result in patients with active TB. A total of 57 patients with active TB who underwent the T-SPOT test with TCX prior to treatment were enrolled between May 2013 and May 2015. One patient with an indeterminate result for T-SPOT was excluded; therefore, the data of 56 patients were eventually included in the final analysis. The basic characteristics and clinical findings were compared between the true-positive and false-negative T-SPOT groups. Of the 56 patients, 40 (71.4%), 13 (23.2%), 3 (5.4%) had true-positive, false-negative, and borderline T-SPOT results, respectively. This study did not reveal any significant risk factors for a false-negative T-SPOT result. In this clinical study, the proportion of patients with a false-negative result for T-SPOT with TCX for active TB was higher than that reported previously. Therefore, careful interpretation of a negative result for T-SPOT with TCX is necessary, regardless of the patient's background.
Impact of false-negative sentinel lymph node biopsy on survival in patients with cutaneous melanoma.
Caracò, C; Marone, U; Celentano, E; Botti, G; Mozzillo, N
2007-09-01
Sentinel lymph node biopsy is widely accepted as standard care in melanoma despite lack of pertinent randomized trials results. A possible pitfall of this procedure is the inaccurate identification of the sentinel lymph node leading to biopsy and analysis of a nonsentinel node. Such a technical failure may yield a different prognosis. The purpose of this study is to analyze the incidence of false negativity and its impact on clinical outcome and to try to understand its causes. The Melanoma Data Base at National Cancer Institute of Naples was analyzed comparing results between false-negative and tumor-positive sentinel node patients focusing on overall survival and prognostic factors influencing the clinical outcome. One hundred fifty-one cases were diagnosed to be tumor-positive after sentinel lymph node biopsy and were subjected to complete lymph node dissection. Thirty-four (18.4%)patients with tumor-negative sentinel node subsequently developed lymph node metastases in the basin site of the sentinel procedure. With a median follow-up of 42.8 months the 5-year overall survival was 48.4% and 66.3% for false-negative and tumor-positive group respectively with significant statistical differences (P < .03). The sensitivity of sentinel lymph node biopsy was 81.6%, and a regional nodal basin recurrence after negative-sentinel node biopsy means a worse prognosis, compared with patients submitted to complete lymph node dissection after a positive sentinel biopsy. The evidence of higher number of tumor-positive nodes after delayed lymphadenectomy in false-negative group compared with tumor-positive sentinel node cases, confirmed the importance of an early staging of lymph nodal involvement. Further data will better clarify the role of prognostic factors to identify cases with a more aggressive biological behavior of the disease.
The Diagnostic Value of Routine Contrast Esophagram in Anastomotic Leaks After Esophagectomy.
Hu, Zhongwu; Wang, Xiaowe; An, Xush; Li, Wenjin; Feng, Yun; You, Zhenbing
2017-08-01
Routine contrast esophagram has been shown to be increasingly limited in diagnosing anastomotic leaks after esophagectomy. Patients undergoing esophagectomy from 2013 to 2014 at Huai'an First Peoples' Hospital were identified. We retrospectively analyzed patients who underwent routine contrast esophagram on postoperative day 7 (range 6-10) to preclude anastomotic leaks after esophagectomy. In 846 patients who underwent esophagectomy, a cervical anastomosis was performed in 286 patients and an intrathoracic anastomosis in 560 patients. There were 57 (6.73%) cases with anastomotic leaks, including cervical leaks in 36 and intrathoracic leaks in 21 patients. In the cervical anastomotic leak patients, 13 were diagnosed by early local clinical symptoms and 23 underwent routine contrast esophagram. There were 7 (30.4%) true-positive, 11 (47.8%) false-negative, and five (21.8%) equivocal cases. In the intrathoracic anastomotic leak patients, four (19%) were diagnosed by clinical symptoms, 16 (76.2%) were true positives, and one (4.8%) was a false negative. Aspiration occurred in five patients with cervical anastomoses and in eight patients with intrathoracic anastomoses; aspiration pneumonitis did not occur in these cases. Gastrografin and barium are safe contrast agents to use in post-esophagectomy contrast esophagram. Because of the low sensitivity in detecting cervical anastomotic leaks, routine contrast esophagram is not advised. For patients with intrathoracic anastomoses, it is still an effective method for detecting anastomotic leaks.
Angeles-Angeles, A; Gamboa-Domínguez, A; Velázquez Fernández, D; Muñoz-Fernández, L
1994-01-01
The results of 114 fine-needle aspiration biopsies (FNAB) of the liver performed during six years (1987-1992) at the Departament of Pathology of the Instituto Nacional de la Nutrición Salvador Zubirán are presented. All were done by radiologists under ultrasonographic (three cases) or computerized tomographic guidance (111 cases). In order to determine the diagnostic accuracy, diagnoses made by FNAB were compared with those made by histological examination (coarse biopsies or surgical specimens) and/or by other diagnostic procedures including the clinical follow-up. Six cases were excluded because clinical information was not available. In 92 cases (85.2%) a correct diagnosis was made, in six (5.5%) the sample was inadequate and in 10 (9.3%) the diagnosis made by FNAB was incorrect. The diagnoses made were as follows: hepatocarcinoma 44, metastatic carcinoma 27, inflammatory lesions 12, regeneration 10, normal eight, unclassified carcinoma five, and lymphoma two. The sensitivity was 96.2, specificity 93.1, positive predictive value 97.4, negative predictive value 90.0, accuracy 95.3 and prevalence 73.1. There were three false negative and two false positive for carcinoma. These figures are similar to those found by other authors. No relevant complications were observed. It is concluded that FNAB of the liver is a safe, inexpensive and reliable method in the diagnoses of liver masses.
[How to manage vertigo in adult?
Vuong Chaney, Hella; Rohmer, Dominique; Charpiot, Anne
2017-11-01
The interrogation and the clinical examination are critical in the research of vertigo etiology. In the context of vertigo, the vital emergencies are of neurological and vascular origins. It is therefore necessary to be able to identify them quickly and simply. Vertigo is a symptom to relieve and the cause is to be diagnosed. Careful questioning combined with neurological examination, nystagmus study, Halmagyi test and skew deviation search are more reliable than imaging in the first 48hours to detect a stroke. There are 12% false negatives in cerebral MRI and 74% false negative in cerebral CT-scan in the first 48hours of an ischemic stroke. Labyrinth emergencies are infectious labyrinthitis, perilymphatic fistula and aeroembolism of the vestibule. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Mori, Miki; Akashi-Tanaka, Sadako; Suzuki, Satoko; Daniels, Murasaki Ikeda; Watanabe, Chie; Hirose, Masanori; Nakamura, Seigo
2017-01-01
Contrast-enhanced spectral mammography to compare clinical efficacy of contrast-enhanced spectral mammography (CESM) and conventional digital mammography (MMG) with histopathology as gold standard in dense breasts. A total of 143 breasts of 72 women who underwent CESM and MMG between 2011 and 2014 at Showa University Hospital were analyzed. 129 (90.2 %) of 143 breasts revealed dense breasts on MMG. 58 (40.6 %) of 143 breasts were diagnosed with breast cancer at histopathology. The remaining 85 breasts were diagnosed with benign findings after image assessments and/or core needle biopsy. CESM revealed 8 false-negative cases among 58 breast cancer cases (sensitivity 86.2 %) and 5 false-positive cases (specificity 94.1 %). Accuracy was 90.9 %. Conventional MMG was assessed true positive in 31 of 58 breast cancer cases (sensitivity 53.4 %) and false positive in 12 cases (specificity 85.9 %). Accuracy was 72.7 %. Sensitivity (p < 0.001), specificity (p = 0.016) and accuracy (p < 0.001) were significantly higher on CESM compared to MMG. MMG missed malignancy in 27 breasts. Of these, 25 were dense breasts. Of these 25, 20 (80.0 %) breasts were positive on CESM. These findings suggest that CESM offers superior clinical performance compared to MMG. Use of CESM may decrease false negatives especially for women with dense breasts.
Blanch, Jordi; Sala, Maria; Ibáñez, Josefa; Domingo, Laia; Fernandez, Belén; Otegi, Arantza; Barata, Teresa; Zubizarreta, Raquel; Ferrer, Joana; Castells, Xavier; Rué, Montserrat; Salas, Dolores
2014-01-01
Background Interval cancers are primary breast cancers diagnosed in women after a negative screening test and before the next screening invitation. Our aim was to evaluate risk factors for interval cancer and their subtypes and to compare the risk factors identified with those associated with incident screen-detected cancers. Methods We analyzed data from 645,764 women participating in the Spanish breast cancer screening program from 2000–2006 and followed-up until 2009. A total of 5,309 screen-detected and 1,653 interval cancers were diagnosed. Among the latter, 1,012 could be classified on the basis of findings in screening and diagnostic mammograms, consisting of 489 true interval cancers (48.2%), 235 false-negatives (23.2%), 172 minimal-signs (17.2%) and 114 occult tumors (11.3%). Information on the screening protocol and women's characteristics were obtained from the screening program registry. Cause-specific Cox regression models were used to estimate the hazard ratios (HR) of risks factors for interval cancer and incident screen-detected cancer. A multinomial regression model, using screen-detected tumors as a reference group, was used to assess the effect of breast density and other factors on the occurrence of interval cancer subtypes. Results A previous false-positive was the main risk factor for interval cancer (HR = 2.71, 95%CI: 2.28–3.23); this risk was higher for false-negatives (HR = 8.79, 95%CI: 6.24–12.40) than for true interval cancer (HR = 2.26, 95%CI: 1.59–3.21). A family history of breast cancer was associated with true intervals (HR = 2.11, 95%CI: 1.60–2.78), previous benign biopsy with a false-negatives (HR = 1.83, 95%CI: 1.23–2.71). High breast density was mainly associated with occult tumors (RRR = 4.92, 95%CI: 2.58–9.38), followed by true intervals (RRR = 1.67, 95%CI: 1.18–2.36) and false-negatives (RRR = 1.58, 95%CI: 1.00–2.49). Conclusion The role of women's characteristics differs among interval cancer subtypes. This information could be useful to improve effectiveness of breast cancer screening programmes and to better classify subgroups of women with different risks of developing cancer. PMID:25333936
Why does cervical cancer occur in a state-of-the-art screening program?
Castle, Philip E; Kinney, Walter K; Cheung, Li C; Gage, Julia C; Fetterman, Barbara; Poitras, Nancy E; Lorey, Thomas S; Wentzensen, Nicolas; Befano, Brian; Schussler, John; Katki, Hormuzd A; Schiffman, Mark
2017-09-01
The goal of cervical screening is to detect and treat precancers before some become cancer. We wanted to understand why, despite state-of-the-art methods, cervical cancers occured in relationship to programmatic performance at Kaiser Permanente Northern California (KPNC), where >1,000,000 women aged ≥30years have undergone cervical cancer screening by triennial HPV and cytology cotesting since 2003. We reviewed clinical histories preceding cervical cancer diagnoses to assign "causes" of cancer. We calculated surrogate measures of programmatic effectiveness (precancers/(precancers and cancers)) and diagnostic yield (precancers and cancers per 1000 cotests), overall and by age at cotest (30-39, 40-49, and ≥50years). Cancer was rare and found mainly in a localized (treatable) stage. Of 623 cervical cancers with at least one preceding or concurrent cotest, 360 (57.8%) were judged to be prevalent (diagnosed at a localized stage within one year or regional/distant stage within two years of the first cotest). Non-compliance with recommended screening and management preceded 9.0% of all cancers. False-negative cotests/sampling errors (HPV and cytology negative), false-negative histologic diagnoses, and treatment failures preceded 11.2%, 9.0%, and 4.3%, respectively, of all cancers. There was significant heterogeneity in the causes of cancer by histologic category (p<0.001 for all; p=0.002 excluding prevalent cases). Programmatic effectiveness (95.3%) and diagnostic yield were greater for squamous cell versus adenocarcinoma histology (p<0.0001) and both decreased with older ages (p trend <0.0001). A state-of-the-art intensive screening program results in very few cervical cancers, most of which are detected early by screening. Screening may become less efficient at older ages. Copyright © 2017 Elsevier Inc. All rights reserved.
Cognitive errors: thinking clearly when it could be child maltreatment.
Laskey, Antoinette L
2014-10-01
Cognitive errors have been studied in a broad array of fields, including medicine. The more that is understood about how the human mind processes complex information, the more it becomes clear that certain situations are particularly susceptible to less than optimal outcomes because of these errors. This article explores how some of the known cognitive errors may influence the diagnosis of child abuse, resulting in both false-negative and false-positive diagnoses. Suggested remedies for these errors are offered. Copyright © 2014 Elsevier Inc. All rights reserved.
Fine needle aspiration cytology.
Lever, J V; Trott, P A; Webb, A J
1985-01-01
Fine needle aspiration cytology is an inexpensive, atraumatic technique for the diagnosis of disease sites. This paper describes the technique and illustrates how it may be applied to the management of tumours throughout the body. The limitations of the method, the dangers of false positive reports, and the inevitability of false negative diagnoses are emphasised. In a clinical context the method has much to offer by saving patients from inappropriate operations and investigations and allowing surgeons to plan quickly and more rationally. It is an economically valuable technique and deserves greater recognition. Images PMID:2578481
Tuberculosis in HIV-infected South African children with complicated severe acute malnutrition.
Adler, H; Archary, M; Mahabeer, P; LaRussa, P; Bobat, R A
2017-04-01
Academic tertiary referral hospital in Durban, South Africa. To describe the incidence and diagnostic challenges of tuberculosis (TB) in human immunodeficiency virus (HIV) infected children with severe acute malnutrition (SAM). Post-hoc analysis of a randomised controlled trial that enrolled antiretroviral therapy naïve, HIV-infected children with SAM. Trial records and hospital laboratory results were explored for clinical diagnoses and bacteriologically confirmed cases of TB. Negative binomial regression was used to explore associations with confirmed cases of TB, excluding cases where the clinical diagnosis was not supported by microbiological confirmation. Of 82 children enrolled in the study, 21 (25.6%) were diagnosed with TB, with bacteriological confirmation in 8 cases. Sputum sampling (as opposed to gastric washings) was associated with an increased risk of subsequent diagnosis of TB (adjusted relative risk [aRR] 1.134, 95%CI 1.02-1.26). Culture-proven bacterial infection during admission was associated with a reduced risk of TB (aRR 0.856, 95%CI 0.748-0.979), which may reflect false-negative microbiological tests secondary to empiric broad-spectrum antibiotics. TB is common in HIV-infected children with SAM. While microbiological confirmation of the diagnosis is feasible, empiric treatment remains common, possibly influenced by suboptimal testing and false-negative TB diagnostics. Rigorous microbiological TB investigation should be integrated into the programmatic management of HIV and SAM.
Dassanayake, Dinesh L B; Wimalaratna, Harith; Agampodi, Suneth B; Liyanapathirana, Veranja C; Piyarathna, Thibbotumunuwe A C L; Goonapienuwala, Bimba L
2009-04-22
Leptospirosis is endemic in both urban and rural areas of Sri Lanka and there had been many out breaks in the recent past. This study was aimed at validating the leptospirosis surveillance case definition, using the Microscopic Agglutination Test (MAT). The study population consisted of patients with undiagnosed acute febrile illness who were admitted to the medical wards of the Teaching Hospital Kandy, from 1st July 2007 to 31st July 2008. The subjects were screened to diagnose leptospirosis according to the leptospirosis case definition. MAT was performed on blood samples taken from each patient on the 7th day of fever. Leptospirosis case definition was evaluated in regard to sensitivity, specificity and predictive values, using a MAT titre >or= 1:800 for confirming leptospirosis. A total of 123 patients were initially recruited of which 73 had clinical features compatible with the surveillance case definition. Out of the 73 only 57 had a positive MAT result (true positives) leaving 16 as false positives. Out of the 50 who didn't have clinical features compatible with the case definition 45 had a negative MAT as well (true negatives), therefore 5 were false negatives. Total number of MAT positives was 62 out of 123. According to these results the test sensitivity was 91.94%, specificity 73.77%, positive predictive value and negative predictive values were 78.08% and 90% respectively. Diagnostic accuracy of the test was 82.93%. This study confirms that the surveillance case definition has a very high sensitivity and negative predictive value with an average specificity in diagnosing leptospirosis, based on a MAT titre of >or= 1: 800.
Half, Elizabeth E; Mlynarsky, Liat; Naftali, Timna; Benjaminov, Fabiana; Konikoff, Fred M
2013-09-01
Fecal Occult Blood Test (FOBT) is an accepted screening test for colorectal cancer (CRC). It has been shown to decrease mortality by up to 30%. The outcome of screening failures has not been adequately studied. The purpose of this study was to assess the outcome of patients who were diagnosed with CRC after a false negative FOBT. We identified all consecutive CRCs from pathology reports between 2005 and 2010. Patients were divided according to their FOBT result. Those who became positive were compared to patients who remained negative. Altogether 401 CRCs were identified. Of those, 202 never performed a FOBT. At least one negative FOBT was performed by 133 individuals (67%). Of these, 76 remained negative (false negatives, FN) and 57 became positive (positive conversion, PC, controls). The prevalence of metastatic disease was threefold higher among the FNs as compared to the PC group (16 [22.2%] vs. 4 [7.5%], P=0.022). All-cause mortality was also significantly higher among FNs versus PCs (24 [31.6%] vs. 5 [8.8%], P=0.001); in Cox regression analysis of survival (covariates: FNs vs. PC, gender, age, medications and co-morbidities) FNs had increased mortality compared to the PC (HR 2.929, P=0.033, CI 95% 1.092-7.858). No statistically significant difference was found regarding all primary end points when comparing the FN and the "No test" group. These data disclose a particular risk of FOBT as a screening test. A subgroup of patients with "false" negative tests may have increased morbidity and mortality. Efforts should be made to recognize and characterize this high-risk group.
Computerized tomography tailored for the assessment of microscopic hematuria.
Lang, Erich K; Macchia, Richard J; Thomas, Raju; Ruiz-Deya, Gilberto; Watson, Richard A; Richter, Frank; Irwin R, Robert; Marberger, Michael; Mydlo, Jack; Lechner, Gerhard; Cho, Kyunghee C; Gayle, Brian
2002-02-01
We report the results of a multicenter study of arterial, corticomedullary, nephrographic and excretory phase helical computerized tomography (CT) for detecting and characterizing abnormalities causing asymptomatic microscopic hematuria. We evaluated 350 consecutive patients, including 216 men and 134 women 23 to 88 years old, with asymptomatic microscopic hematuria of undetermined cause at 4 medical centers. Patients with known urological pathology were excluded from study. We performed 4 helical CT sequences, including pre-enhancement phase imaging from kidney to symphysis pubis, arterial phase imaging of the kidney and lower pelvis, corticomedullary nephrographic phase imaging of the kidney and lower pelvis, and excretory phase imaging from kidney to symphysis pubis with 2 to 5 mm. collimation and 1 to 1.5 pitch. Of 171 proved lesions 158 were correctly diagnosed. There were 10 false-positive and 13 false-negative diagnoses, indicating 0.9239 sensitivity, 0.9441 specificity, 0.9404 positive and 0.9285 negative predictive values, (p <0.001). All cases of congenital renal lesions, calculous disease, ureteral lesion and neoplastic lesion of the bladder were correctly diagnosed, as were 40 of 41 inflammatory renal, 21 of 23 renal masses and 13 of 16 inflammatory bladder lesions. In 27 patients with renal calculi the study was limited to pre-enhancement spiral CT. A positive diagnosis rate of 45.1% (158 of 350 cases) for the causes of heretofore refractory cases of hematuria with high sensitivity and specificity attest to the effectiveness of our hematuria CT protocol and support its use.
Prieto García, M A; Delgado Sevillano, R; Baldó Sierra, C; González Díaz, E; López Secades, A; Llavona Amor, J A; Vidal Marín, B
2013-09-01
To review and classify the interval cancers found in the Principality of Asturias's Breast Cancer Screening Program (PDPCM). A secondary objective was to determine the histological characteristics, size, and stage of the interval cancers at the time of diagnosis. We included the interval cancers in the PDPCM in the period 2003-2007. Interval cancers were classified according to the breast cancer screening program protocol, with double reading without consensus, without blinding, with arbitration. Mammograms were interpreted by 10 radiologists in the PDPCM. A total of 33.7% of the interval cancers could not be classified; of the interval cancers that could be classified, 40.67% were labeled true interval cancers, 31.4% were labeled false negatives on screening, 23.7% had minimal signs, and 4.23% were considered occult. A total of 70% of the interval cancers were diagnosed in the year of the period between screening examinations and 71.7% were diagnosed after subsequent screening. A total of 76.9% were invasive ductal carcinomas, 61.1% were stage II when detected, and 78.7% were larger than 10mm when detected. The rate of interval cancers and the rate of false negatives in the PDPCM are higher than those recommended in the European guidelines. Interval cancers are diagnosed later than the tumors detected at screening. Studying interval cancers provides significant training for the radiologists in the PDPCM. Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.
Saleh, Langeza; Verdonk, Koen; Jan Danser, A H; Steegers, Eric A P; Russcher, Henk; van den Meiracker, Anton H; Visser, Willy
2016-04-01
To evaluate the additive value of the sFlt-1/PlGF ratio for diagnosing preeclampsia (PE) and predicting prolongation of pregnancy and adverse outcome in a cohort of women with PE or at high risk of PE. Patients with suspected or confirmed clinical PE were recruited. At time of inclusion blood for measurement of sFlt-1and PlGF was taken. Values were determined after delivery. A cut-off ratio of ≥85 was defined as a positive test. A total of 107 patients were included. Of the patients, 62 (58%) met the clinical criteria of PE at time of blood sampling. In 10% of these patients (n=6) the ratio was <85 (false negative), whereas in 7% (n=3) of patients without clinical PE the ratio was ≥85 (false positive), resulting in positive and negative predictive values of 95% and 88% respectively. One patient with false positive ratio developed superimposed PE and 2 developed gestational hypertension, and adverse outcome occurred in all three. An adverse pregnancy outcome was only encountered in 1 of the 6 patients with a false negative ratio. Using a binary regression model with adjustment for gestational age <34 weeks, the adverse outcome risk was 11 times increased on the basis of clinical PE, and 30 times on the basis of an elevated ratio (P=0.036). The additive value of an increased ratio for diagnosing PE is limited since most patients with clinical PE also have a positive ratio. However, an elevated ratio is superior to the clinical diagnosis of PE for predicting an adverse pregnancy outcome. Furthermore, irrespective of clinical PE, a low ratio is inversely correlated with prolongation of pregnancy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Sharma, S. T.; Raff, H.
2011-01-01
Context: Anomalous venous drainage can lead to false-negative inferior petrosal sinus sampling (IPSS) results. Baseline inferior petrosal sinus to peripheral (IPS/P) prolactin ratio higher than 1.8 ipsilateral to the highest ACTH ratio has been proposed to verify successful catheterization. Prolactin-normalized ACTH IPS/P ratios may differentiate Cushing's disease (CD) from ectopic ACTH syndrome (EAS). Objective: Our objective was to examine the utility of prolactin measurement during IPSS. Design, Setting, and Participants: We conducted a retrospective analysis of prolactin levels in basal and CRH-stimulated IPSS samples in ACTH-dependent Cushing's syndrome (2007–2010). Results: Twenty-five of 29 patients had a pathologically proven diagnosis (17 CD and eight EAS). IPSS results were partitioned into true positive for CD (n = 16), true negative (n = 7), false negative (n = 1), and false positive (n = 1). Prolactin IPS/P ratio suggested successful IPSS in eight of 11 with abnormal venograms. Baseline prolactin IPS/P ratio was helpful in two patients with abnormal venograms and false-negative (catheterization unsuccessful) or true-negative (catheterization successful) IPSS results; the normalized ratio correctly diagnosed their disease. Normalized ACTH IPS/P ratio was at least 1.3 in all with CD, but prolactin IPS/P ratios were misleadingly low in two. One patient with cyclic EAS had a false-positive IPSS when eucortisolemic (baseline prolactin IPS/P = 1.7; normalized ratio = 5.6). All other EAS patients had normalized ratios no higher than 0.7. Conclusion: Prolactin measurement and evaluation of the venogram can improve diagnostic accuracy when IPSS results suggest EAS but is not necessary with positive IPSS results. Confirmation of hypercortisolemia remains a prerequisite for IPSS. A normalized ratio of 0.7–1.3 was not diagnostic. PMID:22031511
Shanks, Leslie; Siddiqui, M Ruby; Abebe, Almaz; Piriou, Erwan; Pearce, Neil; Ariti, Cono; Masiga, Johnson; Muluneh, Libsework; Wazome, Joseph; Ritmeijer, Koert; Klarkowski, Derryck
2015-05-14
Current WHO testing guidelines for resource limited settings diagnose HIV on the basis of screening tests without a confirmation test due to cost constraints. This leads to a potential risk of false positive HIV diagnosis. In this paper, we evaluate the dilution test, a novel method for confirmation testing, which is simple, rapid, and low cost. The principle of the dilution test is to alter the sensitivity of a rapid diagnostic test (RDT) by dilution of the sample, in order to screen out the cross reacting antibodies responsible for falsely positive RDT results. Participants were recruited from two testing centres in Ethiopia where a tiebreaker algorithm using 3 different RDTs in series is used to diagnose HIV. All samples positive on the initial screening RDT and every 10th negative sample underwent testing with the gold standard and dilution test. Dilution testing was performed using Determine™ rapid diagnostic test at 6 different dilutions. Results were compared to the gold standard of Western Blot; where Western Blot was indeterminate, PCR testing determined the final result. 2895 samples were recruited to the study. 247 were positive for a prevalence of 8.5 % (247/2895). A total of 495 samples underwent dilution testing. The RDT diagnostic algorithm misclassified 18 samples as positive. Dilution at the level of 1/160 was able to correctly identify all these 18 false positives, but at a cost of a single false negative result (sensitivity 99.6 %, 95 % CI 97.8-100; specificity 100 %, 95 % CI: 98.5-100). Concordance between the gold standard and the 1/160 dilution strength was 99.8 %. This study provides proof of concept for a new, low cost method of confirming HIV diagnosis in resource-limited settings. It has potential for use as a supplementary test in a confirmatory algorithm, whereby double positive RDT results undergo dilution testing, with positive results confirming HIV infection. Negative results require nucleic acid testing to rule out false negative results due to seroconversion or misclassification by the lower sensitivity dilution test. Further research is needed to determine if these results can be replicated in other settings. ClinicalTrials.gov, NCT01716299 .
Ahmadinejad, Mojtaba; Aliepour, Asghar; Anbari, Khatereh; Kaviani, Mojhgan; Ganjizadeh, Hasan; Nadri, Sedigheh; Foroutani, Niloufar; Meysami, Masoumeh; Almasi, Vahid
2015-12-01
Several methods are used to evaluate the thyroid nodules. The aim of this study was to determine the sensitivity, specificity, false positive and negative rates, positive predictive value (PPV), and negative predictive value (NPV) of touch imprint, crush preparation, and fine-needle aspiration (FNA) methods. This cross-sectional study was done in Shohada-ye Ashayer University Hospital in Khorramabad. All the patients who underwent thyroid surgery due to thyroid nodules in this hospital between March and September 2011 were evaluated. The thyroid nodules of all the patients were evaluated by touch imprint, crush preparation, FNA, and permanent pathology methods. Finally, the results of the first three methods were compared with the result of permanent pathology method. The mean age of 104 patients who underwent thyroid surgery was 42.6 ± 11.9 years old. Based on permanent pathology, touch imprint, crush preparation, and FNA methods, 15.3, 6.25, 6.25, and 4.4 % of thyroid nodules were malignant, respectively. Sensitivity, specificity, false positive rate, false negative rate, PPV, and NPV of FNA biopsy were 62.5, 100, 0, 37.5, 100, and 95.3 %, respectively. Also, sensitivity, specificity, false positive rate, false negative rate, PPV, and NPV of touch imprint and crush preparation were equal and were 80, 100, 0, 20, 100, and 96.7 %, respectively. Using touch imprint and crush preparation in evaluation of thyroid nodules for rapid evaluation of these nodules in operating rooms seems to be logical, and it can prevent further surgeries.
Rosenfield, Lana; Kalicinsky, Chrystyna; Warrington, Richard
2015-01-01
A history of penicillin allergy in patients is common, but only 10-15 % are truly allergic. While the gold standard for diagnosing penicillin allergy is challenge, it is not recommended that this be done without first carrying out diagnostic skin testing. This is carried out with the major determinant benzylpenicilloyl (PPL) and the minor determinant mixture (MDM), consisting of penilloate, penicilloate and Penicillin G. However, since availability of the MDM is limited, Penicillin G alone has been used. A retrospective chart review was carried out on patients tested for penicillin allergy in the Clinical Immunology and Allergy Clinic at the Health Sciences Centre, Winnipeg, Canada between 2005 and 2013. A total of 521 patients charts were reviewed, of whom 240 had skin testing, ImmunoCap(®) for IgE to Penicillin G and V and had oral challenges with penicillin, amoxicillin or cloxacillin. 17/240 (7.5 %) were skin test positive, 8 to PPL, 4 to MDM and 5 to Penicillin G. One was also positive on ImmunoCap(®) testing. Three patients had negative skin tests but weakly positive ImmunoCap(®). 222 patients with negative skin tests and serological tests were challenged. Of these, 12 patients reacted to challenge. Three of the challenges were equivocal. Of the nine patients with definite positive challenges, three were tested with Penicillin G and six with MDM. Therefore the false negative rates for testing were 2.3 % with PPL and Penicillin G and 6.97 % for PPL and MDM. The difference was not significant (p = 0.0856). In this group of patients with a history of penicillin allergy tested with the major determinant of benzyl penicillin and either MDM or Penicillin G, there was no difference in the rate of false negative testing, based on oral penicillin challenges. Therefore, Penicillin G can be safely used as an alternative to MDM in diagnosing penicillin allergy.
Martínez-Pacheco, María C; Ferrán de la Cierva, Luis; García-Purriños, Francisco J
Despite its importance, the existence of false negatives (patients who are told they hear well, but they have some degree of hipacusia) is rarely evaluated in programs for early detection of hearing loss. The aim of this study is to determine the variables that can lead to a delayed diagnosis, especially the existence of false negatives and the lack of registration of risk factors. A retrospective study of prevalence has been carried out, in which the medical records of children diagnosed with sensorineural hearing loss born within 2005 and 2012 in the health centers of study have been analyzed. Of the 32 children with sensorineural hearing loss, 16 passed the OAE, 12 did not passed the OAE, and in four they were not carried out. Of the children who passed the OAE, 57% have severe hearing loss. 66% of children with hearing loss presented a risk factor for hearing loss at birth, being the most frecuent family history of hearing loss, but only 7% of those with family history of hearing loss were included in the risk group. The results of the study indicate that the late diagnosis of hearing loss is related to the presence of false negatives to the OAE and the non-registration of risk factors. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.
Diagnosing the occult contralateral inguinal hernia.
Koehler, R H
2002-03-01
The incidence of bilateral inguinal hernias reported for total extra peritoneal (TEP) laparoscopic hernia repair, which reaches 45%, appears to be higher than that seen in studies of transabdominal laparoscopic and open repair. Given the unique ability of diagnostic laparoscopy to diagnose occult contralateral hernias (OCH) accurately, this study looked at how concurrent transabdominal diagnostic laparoscopy (TADL) would influence planned TEP repairs. A prospective study oF 100 consecutive TEP cases was conducted. All patients had diagnostic laparoscopy via a 5-mm 45 degrees scope through an umbilical incision with 15 mmHg of pneumoperitoneum, followed by laparoscopic TEPrepair. A contralateral occult hernia was diagnosed and repaired if a true peritoneal eventration through the inguinal region was observed. Among the 100 patients, preoperative diagnosis suggested 31 bilateral hernias (31%), whereas TADL confirmed 25 bilateral hernias (25%). Of these 25 bilateral hernias, TADL confirmed 16 that had been diagnosed preoperatively (64%), but excluded 15 contralateral hernias that were incorrectly diagnosed (37%). Transabdominal diagnostic laparoscopy found nine OCHs, representing 36% of all bilateral hernias and 13% of the 69 preoperatively determined unilateral hernias. The preoperative physician examination false-negative rate for contralateral hernias was 36%, and the false-positive rate was 37%. In 26 cases (26%), TADL changed the operative approach. In this study, patients believed to have unilateral inguinal hernias had OCHs in 13% of cases when examined by TADL. The actual bilateral hernia incidence was 25%, with a 37% false-positive rate for preoperatively diagnosed bilateral hernias. The high rate of bilateral hernias reported by the TEP approach alone suggests that some OCH findings may be an artifact of the TEP dissection. However, failure to search for an OCH could result in up to 13% of patients subsequently requiring a second repair. Because some surgeons are concerned about unnecessary TEP dissection of the asymptomatic contralateral side, the approach described here may offer a solution to accurate diagnosis of the contralateral inguinal region during planned laparoscopic TEP hernia repair.
Influence of ECG measurement accuracy on ECG diagnostic statements.
Zywietz, C; Celikag, D; Joseph, G
1996-01-01
Computer analysis of electrocardiograms (ECGs) provides a large amount of ECG measurement data, which may be used for diagnostic classification and storage in ECG databases. Until now, neither error limits for ECG measurements have been specified nor has their influence on diagnostic statements been systematically investigated. An analytical method is presented to estimate the influence of measurement errors on the accuracy of diagnostic ECG statements. Systematic (offset) errors will usually result in an increase of false positive or false negative statements since they cause a shift of the working point on the receiver operating characteristics curve. Measurement error dispersion broadens the distribution function of discriminative measurement parameters and, therefore, usually increases the overlap between discriminative parameters. This results in a flattening of the receiver operating characteristics curve and an increase of false positive and false negative classifications. The method developed has been applied to ECG conduction defect diagnoses by using the proposed International Electrotechnical Commission's interval measurement tolerance limits. These limits appear too large because more than 30% of false positive atrial conduction defect statements and 10-18% of false intraventricular conduction defect statements could be expected due to tolerated measurement errors. To assure long-term usability of ECG measurement databases, it is recommended that systems provide its error tolerance limits obtained on a defined test set.
Hofvind, Solveig; Sagstad, Silje; Sebuødegård, Sofie; Chen, Ying; Roman, Marta; Lee, Christoph I
2018-04-01
Purpose To compare rates and tumor characteristics of interval breast cancers (IBCs) detected after a negative versus false-positive screening among women participating in the Norwegian Breast Cancer Screening Program. Materials and Methods The Cancer Registry Regulation approved this retrospective study. Information about 423 445 women aged 49-71 years who underwent 789 481 full-field digital mammographic screening examinations during 2004-2012 was extracted from the Cancer Registry of Norway. Rates and odds ratios of IBC among women with a negative (the reference group) versus a false-positive screening were estimated by using logistic regression models adjusted for age at diagnosis and county of residence. Results A total of 1302 IBCs were diagnosed after 789 481 screening examinations, of which 7.0% (91 of 1302) were detected among women with a false-positive screening as the most recent breast imaging examination before detection. By using negative screening as the reference, adjusted odds ratios of IBCs were 3.3 (95% confidence interval [CI]: 2.6, 4.2) and 2.8 (95% CI: 1.8, 4.4) for women with a false-positive screening without and with needle biopsy, respectively. Women with a previous negative screening had a significantly lower proportion of tumors that were 10 mm or less (14.3% [150 of 1049] vs 50.0% [seven of 14], respectively; P < .01) and grade I tumors (13.2% [147 of 1114] vs 42.9% [six of 14]; P < .01), but a higher proportion of cases with lymph nodes positive for cancer (40.9% [442 of 1080] vs 13.3% [two of 15], respectively; P = .03) compared with women with a previous false-positive screening with benign biopsy. A retrospective review of the screening mammographic examinations identified 42.9% (39 of 91) of the false-positive cases to be the same lesion as the IBC. Conclusion By using a negative screening as the reference, a false-positive screening examination increased the risk of an IBC three-fold. The tumor characteristics of IBC after a negative screening were less favorable compared with those detected after a previous false-positive screening. © RSNA, 2017 Online supplemental material is available for this article.
Bertoldi, Eduardo G; Stella, Steffen F; Rohde, Luis Eduardo P; Polanczyk, Carisi A
2017-05-04
The aim of this research is to evaluate the relative cost-effectiveness of functional and anatomical strategies for diagnosing stable coronary artery disease (CAD), using exercise (Ex)-ECG, stress echocardiogram (ECHO), single-photon emission CT (SPECT), coronary CT angiography (CTA) or stress cardiacmagnetic resonance (C-MRI). Decision-analytical model, comparing strategies of sequential tests for evaluating patients with possible stable angina in low, intermediate and high pretest probability of CAD, from the perspective of a developing nation's public healthcare system. Hypothetical cohort of patients with pretest probability of CAD between 20% and 70%. The primary outcome is cost per correct diagnosis of CAD. Proportion of false-positive or false-negative tests and number of unnecessary tests performed were also evaluated. Strategies using Ex-ECG as initial test were the least costly alternatives but generated more frequent false-positive initial tests and false-negative final diagnosis. Strategies based on CTA or ECHO as initial test were the most attractive and resulted in similar cost-effectiveness ratios (I$ 286 and I$ 305 per correct diagnosis, respectively). A strategy based on C-MRI was highly effective for diagnosing stable CAD, but its high cost resulted in unfavourable incremental cost-effectiveness (ICER) in moderate-risk and high-risk scenarios. Non-invasive strategies based on SPECT have been dominated. An anatomical diagnostic strategy based on CTA is a cost-effective option for CAD diagnosis. Functional strategies performed equally well when based on ECHO. C-MRI yielded acceptable ICER only at low pretest probability, and SPECT was not cost-effective in our analysis. © 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.
An audit of intraoperative frozen section in Johor.
Khoo, J J
2004-03-01
A 4-year-review was carried out on intraoperative frozen section consultations in Sultanah Aminah Hospital, Johor Bahru. Two hundred and fifteen specimens were received from 79 patients in the period between January 1999 and December 2002. An average of 2.72 specimens per patient was received. The overall diagnostic accuracy was high, 97.56%. The diagnoses were deferred in 4.65% of the specimens. False positive diagnoses were made in 3 specimens (1.46%) and false negative diagnoses in 2 specimens (0.98%). This gave an error rate of 2.44%. The main cause of error was incorrect interpretation of the pathologic findings. In the present study, frozen sections showed good sensitivity (97.98%) and specificity (97.16%). Despite its limitations, frozen section is still generally considered to be an accurate mode of intraoperative consultation to assist the surgeon in deciding the best therapeutic approach for his patient at the operating table. The use of frozen section with proper indications was cost-effective as it helped lower the number of reoperations. An audit of intraoperative frozen section from time to time serves as part of an ongoing quality assurance program and should be recommended where the service is available.
Kiemde, Francois; Bonko, Massa Dit Achille; Tahita, Marc Christian; Lompo, Palpouguini; Rouamba, Toussaint; Tinto, Halidou; van Hensbroek, Michael Boele; Mens, Petra F; Schallig, Henk D F H
2017-07-20
It remains challenging to distinguish malaria from other fever causing infections, as a positive rapid diagnostic test does not always signify a true active malaria infection. This study was designed to determine the influence of other causes of fever, prior anti-malarial treatment, and a possible seasonality of the performance of a PfHRP2 RDT for the diagnosis of malaria in children under-5 years of age living in a malaria endemic area. A prospective etiology study was conducted in 2015 among febrile children under 5 years of age in Burkina Faso. In order to assess the influence of other febrile illnesses, prior treatment and seasonality on the performance of a PfHRP2 RDT in diagnosing malaria, the RDT results were compared with the gold standard (expert microscopic diagnosis of Plasmodium falciparum) and test results were analysed by assuming that prior anti-malarial use and bacterial/viral infection status would have been known prior to testing. To assess bacterial and viral infection status blood, urine and stool samples were analysed. In total 683 blood samples were analysed with microscopy and RDT-PfHRP2. Plasmodium falciparum malaria was diagnosed in 49.8% (340/683) by microscopy compared to 69.5% (475/683) by RDT-PfHRP2. The RDT-PfHRP2 reported 29.7% (141/475) false positive results and 1.8% (6/340) false negative cases. The RDT-PfHRP2 had a high sensitivity (98.2%) and negative predictive value (97.1%), but a low specificity (58.9%) and positive predictive value (70.3%). Almost 50% of the alternative cause of fever were diagnosed by laboratory testing in the RDT false positive malaria group. The use of a malaria RDT-PfHRP2 in a malaria endemic area may cause misdiagnosis of the actual cause of fever due to false positive test results. The development of a practical diagnostic tool to screen for other causes of fever in malaria endemic areas is required to save lives.
2012-01-01
Background We previously investigated the current status of breast cytology cancer screening at seven institutes in our area of southern Fukuoka Prefecture, and found some differences in diagnostic accuracy among the institutions. In the present study, we evaluated the cases involved and noted possible reasons for their original cytological classification as inadequate, indeterminate, false-negative and false-positive according to histological type. Methods We evaluated the histological findings in 5693 individuals who underwent cytological examination for breast cancer (including inadequate, indeterminate, false-negative and false-positive cases), to determine the most common histological types and/or features in these settings and the usefulness/limitations of cytological examination for the diagnosis of breast cancer. Results Among 1152 cytologically inadequate cases, histology revealed that 75/173 (43.6%) cases were benign, including mastopathy (fibrocystic disease) in 38.6%, fibroadenoma in 24.0% and papilloma in 5.3%. Ninety-five of 173 (54.9%) cases were histologically malignant, with scirrhous growing type, invasive ductal carcinoma (SIDC) being significantly more frequent (49.5%) than papillotubular growing type (Papi-tub) (P < 0.0001), solid-tubular growing type (P = 0.0001) and ductal carcinoma in situ (DCIS) (P = 0.0001). Among 458 indeterminate cases, 54/139 (38.8%) were histologically benign (mastopathy, 30.0%; fibroadenoma, 27.8%; papilloma, 26.0%) and 73/139 (52.5%) were malignant, with SIDC being the most frequent malignant tumor (37.0%). Among 52 false-negative cases, SIDC was significantly more frequent (42.3%) than DCIS (P = 0.0049) and Papi-tub (P = 0.001). There were three false-positive cases, with one each of fibroadenoma, epidermal cyst and papilloma. Conclusions The inadequate, indeterminate, false-negative and false-positive cases showed similar histological types, notably SIDC for malignant tumors, and mastopathy, fibroadenoma and papilloma for benign cases. We need to pay particular attention to the collection and assessment of aspirates for these histological types of breast disease. In particular, several inadequate, indeterminate and false-negative cases with samples collected by aspiration were diagnosed as SIDC. These findings should encourage the use of needle biopsy rather than aspiration when this histological type is identified on imaging. Namely, good communication between clinicians and pathological staff, and triple assessment (i.e., clinical, pathological and radiological assessment), are important for accurate diagnosis of aspiration samples. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/7349809170055423 PMID:22607447
Gene expression information improves reliability of receptor status in breast cancer patients
Kenn, Michael; Schlangen, Karin; Castillo-Tong, Dan Cacsire; Singer, Christian F.; Cibena, Michael; Koelbl, Heinz; Schreiner, Wolfgang
2017-01-01
Immunohistochemical (IHC) determination of receptor status in breast cancer patients is frequently inaccurate. Since it directs the choice of systemic therapy, it is essential to increase its reliability. We increase the validity of IHC receptor expression by additionally considering gene expression (GE) measurements. Crisp therapeutic decisions are based on IHC estimates, even if they are borderline reliable. We further improve decision quality by a responsibility function, defining a critical domain for gene expression. Refined normalization is devised to file any newly diagnosed patient into existing data bases. Our approach renders receptor estimates more reliable by identifying patients with questionable receptor status. The approach is also more efficient since the rate of conclusive samples is increased. We have curated and evaluated gene expression data, together with clinical information, from 2880 breast cancer patients. Combining IHC with gene expression information yields a method more reliable and also more efficient as compared to common practice up to now. Several types of possibly suboptimal treatment allocations, based on IHC receptor status alone, are enumerated. A ‘therapy allocation check’ identifies patients possibly miss-classified. Estrogen: false negative 8%, false positive 6%. Progesterone: false negative 14%, false positive 11%. HER2: false negative 2%, false positive 50%. Possible implications are discussed. We propose an ‘expression look-up-plot’, allowing for a significant potential to improve the quality of precision medicine. Methods are developed and exemplified here for breast cancer patients, but they may readily be transferred to diagnostic data relevant for therapeutic decisions in other fields of oncology. PMID:29100391
Dental pulp neurophysiology: part 2. Current diagnostic tests to assess pulp vitality.
Abd-Elmeguid, Ashraf; Yu, Donald C
2009-03-01
In this second part of our 2-part review, we discuss recent research about pulp tests that determine the vitality of the tooth and clinically accepted pulp testers. A pain response to hot, cold or an electric pulp tester indicates the vitality of only a tooth's pulpal sensory supply; the response does not give any idea about the state of the pulp. Although the sensitivity of these tests is high, when false-positive and false-negative results occur, they may affect the treatment of the tooth. A tooth falsely diagnosed as nonvital with an electric pulp tester may undergo an unnecessary root canal, whereas one falsely diagnosed as vital may be left untreated, causing the necrotic tissue to destroy the supporting tissues (resorption). The vascular supply is more important to the determination of the health of the pulp than the sensory supply. Pulp death is caused by cessation of blood flow and may result in a necrotic pulp, even though the pulpal sensory supply may still be viable. The pulp can be healed only if the circulating blood flow is healthy. Although still under investigation, diagnostic devices that examine pulpal blood flow, such as the pulse oximeter and laser Doppler flowmetry, show promising results for the assessment of pulp vitality.
Lao, Annabelle Y; Sharma, Vijay K; Tsivgoulis, Georgios; Frey, James L; Malkoff, Marc D; Navarro, Jose C; Alexandrov, Andrei V
2008-10-01
International Consensus Criteria (ICC) consider right-to-left shunt (RLS) present when Transcranial Doppler (TCD) detects even one microbubble (microB). Spencer Logarithmic Scale (SLS) offers more grades of RLS with detection of >30 microB corresponding to a large shunt. We compared the yield of ICC and SLS in detection and quantification of a large RLS. We prospectively evaluated paradoxical embolism in consecutive patients with ischemic strokes or transient ischemic attack (TIA) using injections of 9 cc saline agitated with 1 cc of air. Results were classified according to ICC [negative (no microB), grade I (1-20 microB), grade II (>20 microB or "shower" appearance of microB), and grade III ("curtain" appearance of microB)] and SLS criteria [negative (no microB), grade I (1-10 microB), grade II (11-30 microB), grade III (31100 microB), grade IV (101300 microB), grade V (>300 microB)]. The RLS size was defined as large (>4 mm) using diameter measurement of the septal defects on transesophageal echocardiography (TEE). TCD comparison to TEE showed 24 true positive, 48 true negative, 4 false positive, and 2 false negative cases (sensitivity 92.3%, specificity 92.3%, positive predictive value (PPV) 85.7%, negative predictive value (NPV) 96%, and accuracy 92.3%) for any RLS presence. Both ICC and SLS were 100% sensitive for detection of large RLS. ICC and SLS criteria yielded a false positive rate of 24.4% and 7.7%, respectively when compared to TEE. Although both grading scales provide agreement as to any shunt presence, using the Spencer Scale grade III or higher can decrease by one-half the number of false positive TCD diagnoses to predict large RLS on TEE.
INITIAL IMPRESSIONS OF THE DIAGNOSTIC USE OF RADIOACTIVE PHOSPHORUS IN OPHTHALMOLOGY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stankovic, M.
Out of 10 cases, the use of radioactive P established four cases of malignant growths on the retina that were histologically confirmed, but gave falsely positive results in two cases immediately after surgical intervention, and was negative in the other four cases. It was concluded that the method appears justified in diagnosing intraocular tumors if regarded as an auxiliary method and not as the decisive factor. (P.C.H.)
Hwang, Hamish; Marsh, Ian; Doyle, Jason
2014-01-01
Background Acute cholecystitis is one of the most common diseases requiring emergency surgery. Ultrasonography is an accurate test for cholelithiasis but has a high false-negative rate for acute cholecystitis. The Murphy sign and laboratory tests performed independently are also not particularly accurate. This study was designed to review the accuracy of ultrasonography for diagnosing acute cholecystitis in a regional hospital. Methods We studied all emergency cholecystectomies performed over a 1-year period. All imaging studies were reviewed by a single radiologist, and all pathology was reviewed by a single pathologist. The reviewers were blinded to each other’s results. Results A total of 107 patients required an emergency cholecystectomy in the study period; 83 of them underwent ultrasonography. Interradiologist agreement was 92% for ultrasonography. For cholelithiasis, ultrasonography had 100% sensitivity, 18% specificity, 81% positive predictive value (PPV) and 100% negative predictive value (NPV). For acute cholecystitis, it had 54% sensitivity, 81% specificity, 85% PPV and 47% NPV. All patients had chronic cholecystitis and 67% had acute cholecystitis on histology. When combined with positive Murphy sign and elevated neutrophil count, an ultrasound showing cholelithiasis or acute cholecystitis yielded a sensitivity of 74%, specificity of 62%, PPV of 80% and NPV of 53% for the diagnosis of acute cholecystitis. Conclusion Ultrasonography alone has a high rate of false-negative studies for acute cholecystitis. However, a higher rate of accurate diagnosis can be achieved using a triad of positive Murphy sign, elevated neutrophil count and an ultrasound showing cholelithiasis or cholecystitis. PMID:24869607
Brownback, Kyle R; Pitts, Lucas R; Simpson, Steven Q
2013-09-01
Diagnosis of invasive pulmonary aspergillosis (IPA) is a challenging process in immunocompromised patients. Galactomannan (GM) antigen detection in bronchoalveolar lavage (BAL) fluid is a method to detect IPA with improved sensitivity over conventional studies. We sought to determine the diagnostic yield of BAL GM assay in a diverse population of immunocompromised patients. A retrospective review of 150 fiberoptic bronchoscopy (FOB) with BAL for newly diagnosed pulmonary infiltrate in immunocompromised patients was performed. Patient information, procedural details and laboratory studies were collected. BAL and serum samples were evaluated for GM using enzyme-linked immunoassay. Of 150 separate FOB with BAL, BAL GM was obtained in 143 samples. There were 31 positive BAL GM assays. In those 31 positive tests, 13 were confirmed as IPA, giving a positive predictive value of 41.9%. There was one false negative BAL GM. Of the 18 false positive BAL GM, 4 were receiving piperacillin-tazobactam and 11 were receiving an alternative beta-lactam antibiotic. BAL GM assay shows excellent sensitivity for diagnosing IPA. There was a significant number of false positive BAL GM assays and several of those patients were receiving beta-lactam antibiotics at the time of bronchoscopy. © 2013 Blackwell Verlag GmbH.
Dual-energy CT for the diagnosis of gout: an accuracy and diagnostic yield study.
Bongartz, Tim; Glazebrook, Katrina N; Kavros, Steven J; Murthy, Naveen S; Merry, Stephen P; Franz, Walter B; Michet, Clement J; Veetil, Barath M Akkara; Davis, John M; Mason, Thomas G; Warrington, Kenneth J; Ytterberg, Steven R; Matteson, Eric L; Crowson, Cynthia S; Leng, Shuai; McCollough, Cynthia H
2015-06-01
To assess the accuracy of dual-energy CT (DECT) for diagnosing gout, and to explore whether it can have any impact on clinical decision making beyond the established diagnostic approach using polarising microscopy of synovial fluid (diagnostic yield). Diagnostic single-centre study of 40 patients with active gout, and 41 individuals with other types of joint disease. Sensitivity and specificity of DECT for diagnosing gout was calculated against a combined reference standard (polarising and electron microscopy of synovial fluid). To explore the diagnostic yield of DECT scanning, a third cohort was assembled consisting of patients with inflammatory arthritis and risk factors for gout who had negative synovial fluid polarising microscopy results. Among these patients, the proportion of subjects with DECT findings indicating a diagnosis of gout was assessed. The sensitivity and specificity of DECT for diagnosing gout was 0.90 (95% CI 0.76 to 0.97) and 0.83 (95% CI 0.68 to 0.93), respectively. All false negative patients were observed among patients with acute, recent-onset gout. All false positive patients had advanced knee osteoarthritis. DECT in the diagnostic yield cohort revealed evidence of uric acid deposition in 14 out of 30 patients (46.7%). DECT provides good diagnostic accuracy for detection of monosodium urate (MSU) deposits in patients with gout. However, sensitivity is lower in patients with recent-onset disease. DECT has a significant impact on clinical decision making when gout is suspected, but polarising microscopy of synovial fluid fails to demonstrate the presence of MSU crystals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Kwon, Yong Hwan; Kim, Nayoung; Lee, Ju Yup; Choi, Yoon Jin; Yoon, Kichul; Hwang, Jae Jin; Lee, Hyun Joo; Lee, AeRa; Jeong, Yeon Sang; Oh, Sooyeon; Yoon, Hyuk; Shin, Cheol Min; Park, Young Soo; Lee, Dong Ho
2015-06-01
The (13)C-urea breath test ((13)C-UBT) is a noninvasive method for diagnosing Helicobacter pylori (H. pylori) infection. The aims of this study were to evaluate the diagnostic validity of the (13)C-UBT cutoff value and to identify influencing clinical factors responsible for aberrant results. (13)C-UBT (UBiTkit; Otsuka Pharmaceutical, cutoff value: 2.5‰) results in the range 2.0‰ to 10.0‰ after H. pylori eradication therapy were compared with the results of endoscopic biopsy results of the antrum and body. Factors considered to affect test results adversely were analyzed. Among patients with a positive (13)C-UBT result (2.5‰ to 10.0‰, n = 223) or a negative (13)C-UBT result (2.0‰ to < 2.5‰, n = 66) after H. pylori eradication, 73 patients (34.0%) were false positive, and one (1.5%) was false negative as determined by endoscopic biopsy. The sensitivity, specificity, false-positive rate, and false-negative rate for a cutoff value of 2.5‰ were 99.3%, 47.1%, 52.9%, and 0.7%, respectively, and positive and negative predictive values of the (13)C-UBT were 67.3% and 98.5%, respectively. Multivariate analysis showed that a history of two or more previous H. pylori eradication therapies (OR = 2.455, 95%CI = 1.299-4.641) and moderate to severe gastric intestinal metaplasia (OR = 3.359, 95%CI = 1.572-7.178) were associated with a false-positive (13)C-UBT result. The (13)C-UBT cutoff value currently used has poor specificity for confirming H. pylori status after eradication, and this lack of specificity is exacerbated in patients that have undergone multiple prior eradication therapies and in patients with moderate to severe gastric intestinal metaplasia. In addition, the citric-free (13)C-UBT would increase a false-positive (13)C-UBT result. © 2015 John Wiley & Sons Ltd.
Breast cancer in tough economic times: disruptive technology emerging
NASA Astrophysics Data System (ADS)
Bretz, Phillip; Lynch, Richard
2012-06-01
The objective of this study was to investigate the efficacy of melding three emerging technologies: Pharmacogenomics, Modified Military Digital Infrared and Halo to establish their capability in diagnosing ultra-small breast cancers as well as other cancers. Mammography, ultrasound and MRI technologies have been available for over forty years, however, there is still no uniform utilization by women, costs continue to escalate and problems persist like high false positive rates for MRI and high false negative rates for mammography. Of the first 500 IR patients, 499 were female and 1 male. Of 550 OncoVue patients, 129 opted to undergo IR. A total of 19 were lost to follow-up. Patients who were negative on IR: 419/500 (84%). Of these, 63/419 went to biopsy because of findings of other diagnostic modalities. Of these 61/63 with negative IR had a negative biopsy. Of two missed, one was the fault of the investigator but was included. In this series 2/500 were false negative (0.4%). The sensitivity was 96% and the specificity was 79%. In total, 46 cancers were identified including five outside the breast (e.g. 2 lung cancers). A total of 92 MRIs were done and in 71/92 patients IR and MRI agreed. Using these three modalities the smallest cancer found was a 4 mm invasive cancer. The study demonstrated that these diagnostic techniques can dramatically lower cost and provide results at least as good as the older paradigms. Further research and a multicenter clinical trial are necessary to shift the paradigm of breast cancer diagnosis and treatment.
Østergaard, Mia L; Nielsen, Kristina R; Albrecht-Beste, Elisabeth; Konge, Lars; Nielsen, Michael B
2018-01-01
This study aimed to develop a test with validity evidence for abdominal diagnostic ultrasound with a pass/fail-standard to facilitate mastery learning. The simulator had 150 real-life patient abdominal scans of which 15 cases with 44 findings were selected, representing level 1 from The European Federation of Societies for Ultrasound in Medicine and Biology. Four groups of experience levels were constructed: Novices (medical students), trainees (first-year radiology residents), intermediates (third- to fourth-year radiology residents) and advanced (physicians with ultrasound fellowship). Participants were tested in a standardized setup and scored by two blinded reviewers prior to an item analysis. The item analysis excluded 14 diagnoses. Both internal consistency (Cronbach's alpha 0.96) and inter-rater reliability (0.99) were good and there were statistically significant differences (p < 0.001) between all four groups, except the intermediate and advanced groups (p = 1.0). There was a statistically significant correlation between experience and test scores (Pearson's r = 0.82, p < 0.001). The pass/fail-standard failed all novices (no false positives) and passed all advanced (no false negatives). All intermediate participants and six out of 14 trainees passed. We developed a test for diagnostic abdominal ultrasound with solid validity evidence and a pass/fail-standard without any false-positive or false-negative scores. • Ultrasound training can benefit from competency-based education based on reliable tests. • This simulation-based test can differentiate between competency levels of ultrasound examiners. • This test is suitable for competency-based education, e.g. mastery learning. • We provide a pass/fail standard without false-negative or false-positive scores.
Discordance between self-reported arthritis and musculoskeletal signs and symptoms in older women.
Lo, Tkt; Parkinson, Lynne; Cunich, Michelle; Byles, Julie
2016-12-01
Arthritis is a gendered disease where women have a higher prevalence and more disability than men with arthritis of the same age. Health survey data is a major source of information for monitoring of the burden of arthritis. The validity of self-reported arthritis and the determinants of its accuracy among women have not been thoroughly studied. The objectives of this study were to: 1) examine the agreement between self-report diagnosed arthritis and musculoskeletal signs and symptoms in community-living older women; 2) estimate the sensitivity, specificity, and predictive values of self-reported arthritis; and 3) assess the factors associated with the disagreement. A cross-sectional survey of women was undertaken in 2012-13. The health survey asked women about diagnosed arthritis and musculoskeletal signs and symptoms. Agreement between self-reported arthritis and musculoskeletal signs symptoms was measured by Cohen's kappa. Sensitivity, specificity, and predictive values of self-reported arthritis were estimated using musculoskeletal signs and symptoms as the reference standard. Factors associated with disagreement between self-reported arthritis and the reference standard were examined using multiple logistic regression. There were 223 participants self-reported arthritis and 347 did not. A greater number of participants who self-reported arthritis were obese compared to those who did not report arthritis. Those who reported arthritis had worse health, physical functioning, and arthritis symptom measures. Among the 570 participants, 198 had musculoskeletal signs and symptoms suggesting arthritis (the reference standard). Agreement between self-reported arthritis and the reference standard was moderate (kappa = 0.41). Sensitivity, specificity, and positive and negative predictive values of self-reported arthritis in older women were 66.7, 75.5, 59.2, and 81.0% respectively. Regression analysis results indicated that false-positive is associated with better health measured by the Short Form 36 physical summary score, the Health Assessment Questionnaire disability index, or the Western Ontario and McMaster University Osteoarthritis Index total score; whereas false-negative is negatively associated with these variables. While some women who reported diagnosed arthritis did not have recent musculoskeletal signs or symptoms, others with the signs and symptoms did not report diagnosed arthritis. Researchers should use caution when employing self-reported arthritis as the case-definition in epidemiological studies.
[Benefit of clinical and laboratory parameters for the diagnosis of endometritis in dairy cows].
Hässig, M; Steinmann, B; Wittenbrink, M M
2010-09-01
The goal of this work was to answer the question of whether or not there are significant differences between cows with abnormal vaginal discharge and cows with the diagnosis of puerperal or chronic endometritis, using blood and urine parameters. In addition, cows with and without vaginal discharge were examined for significant bacteriological differences in uterine mucous samples. The question of false positive and false negatives from the diagnosis of endometritis was also investigated. A total of 35 matched-pairs (+/-vaginal discharge) from 27 stables was examined 21 to 63 days post partum. The examination consisted of a rectal and vaginal exam, urine and blood samples as well as vaginal swab from the corpus uteri using a Folmer-Nielsen-Catheter. Based on the history vaginal discharge occurred more frequently in dystocia and retentio secundinarium. Cows with a history of distocia and retentio secundinarium showed significantly more vaginal discharge. Gammaglutamyltransferase (GGT; p=0.01) and cholesterine (p=0.04) were different in cows with endometritis. The bacteriology results showed a statistically significant difference (p<0.01) only for Escherichia coli and Arcanobacterium pyogenes. The Folmer-Nielsen smears/endometritis showed a significant difference between the two groups (p<0.01). In a multivariate analysis with final step-back procedure regarding endometritis Gammaglutamyltransferase (GGT) and Betahydroxybutteracid (BHB) were significant different (p=0.02). The hypothesis vaginal discharge alike endometritis showed that 34 % of the clinical suspicious cases were recorded as false negatives. In the non-suspicious cases 20 % were diagnosed as false negative.
Theron, Grant; Venter, Rouxjeane; Smith, Liezel; Esmail, Aliasgar; Randall, Philippa; Sood, Vishesh; Oelfese, Suzette; Calligaro, Greg; Warren, Robin; Dheda, Keertan
2018-03-01
Globally, Xpert MTB/RIF (Xpert) is the most widely used PCR test for the diagnosis of tuberculosis (TB). Positive results in previously treated patients, which are due to old DNA or active disease, are a diagnostic dilemma. We prospectively retested sputum from 238 patients, irrespective of current symptoms, who were previously diagnosed to be Xpert positive and treated successfully. Patients who retested as Xpert positive and culture negative were exhaustively investigated (repeat culture, chest radiography, bronchoscopy with bronchoalveolar lavage, long-term clinical follow-up). We evaluated whether the duration since previous treatment completion, mycobacterial burden (the Xpert cycle threshold [ C T ] value), and reclassification of Xpert-positive results with a very low semiquantitation level to Xpert-negative results reduced the rate of false positivity. A total of 229/238 (96%) of patients were culture negative. Sixteen of 229 (7%) were Xpert positive a median of 11 months (interquartile range, 5 to 19 months) after treatment completion. The specificity was 93% (95% confidence interval [CI], 89 to 96%). Nine of 15 (40%) Xpert-positive, culture-negative patients reverted to Xpert negative after 2 to 3 months (1 patient declined further participation). Patients with false-positive Xpert results had a lower mycobacterial burden than patients with true-positive Xpert results ( C T , 28.7 [95% CI, 27.2 to 30.4] versus 17.6 [95% CI, 16.9 to 18.2]; P < 0.001), an increased likelihood of a chest radiograph not compatible with active TB (5/15 patients versus 0/5 patients; P = 0.026), and less-viscous sputum (15/16 patients versus 2/5 patients whose sputum was graded as mucoid or less; P = 0.038). All patients who initially retested as Xpert positive and culture negative ("Xpert false positive") were clinically well without treatment after follow-up. The duration since the previous treatment poorly predicted false-positive results (a duration of ≤2 years identified only 66% of patients with false-positive results). Reclassifying Xpert-positive results with a very low semiquantitation level to Xpert negative improved the specificity (+3% [95% CI, +2 to +5%]) but reduced the sensitivity (-10% [95% CI, -4 to -15%]). Patients with previous TB retested with Xpert can have false-positive results and thus not require treatment. These data inform clinical practice by highlighting the challenges in interpreting Xpert-positive results, underscore the need for culture, and have implications for next-generation ultrasensitive tests. Copyright © 2018 American Society for Microbiology.
Padoan, R; Genoni, S; Moretti, E; Seia, M; Giunta, A; Corbetta, C
2002-01-01
A study was performed on the delayed diagnosis of cystic fibrosis (CF) in infants who had false-negative results in a neonatal screening programme. The genetic and clinical features of false-negative infants in this screening programme were assessed together with the efficiency of the screening procedure in the Lombardia region. In total, 774,687 newborns were screened using a two-step immunoreactive trypsinogen (IRT) (in the years 1990-1992), IRT/IRT + delF508 (1993-1998) or IRT/IRT + polymerase chain reaction (PCR) and oligonucleotide ligation assay (OLA) protocol (1998-1999). Out of 196 CF children born in the 10 y period 15 were false negative on screening (7.6%) and molecular analysis showed a high variability in the genotypes. The cystic fibrosis transmembrane regulator (CFTR) gene mutations identified were delF508, D1152H, R1066C, R334W, G542X, N1303K, F1052V, A120T, 3849 + 10kbC --> T, 2789 + 5G --> A, 5T-12TG and the novel mutation D110E. In three patients no mutation was identified after denaturing gradient gel electrophoresis of the majority of CFTR gene exons. The clinical phenotypes of CF children diagnosed by their symptoms at different ages were very mild. None of them presented with a severe lung disease. The majority of them did not seem to have been damaged by the delayed diagnosis. The combination of IRT assay plus genotype analysis (1998-1999) appears to be a more reliable method of detecting CF than IRT measurement alone or combined with only the delF508 mutation.
Grey, Katherine R; Warshaw, Erin M
Allergic contact dermatitis is an important cause of periorbital dermatitis. Topical ophthalmic agents are relevant sensitizers. Contact dermatitis to ophthalmic medications can be challenging to diagnose and manage given the numerous possible offending agents, including both active and inactive ingredients. Furthermore, a substantial body of literature reports false-negative patch test results to ophthalmic agents. Subsequently, numerous alternative testing methods have been described. This review outlines the periorbital manifestations, causative agents, and alternative testing methods of allergic contact dermatitis to ophthalmic medications.
[Progress in the early diagnosis of cancer of the colon and rectum].
Canessa, N; Roset, J; Boffi, A; Ferrara, J B; Galano, A; Albertengo, J C
1978-09-01
Our experience with the air contrast examination in the cancer of colon and rectum diagnoses is showed. The colaboration among radiologist, endoscopist, pathologist and surgeon is important. In the large bowel tumors diagnosis, the radiologic and endoscopic prodedures should be evaluated together. The double colonic contrast has showed in our experience, better results than with the barium enema. Over 31 patients with both studies, we obtained 13 false negatives (with barium enema, doing then the double colonic contrast became positive 12 (92.4%).
Shaw, Colette M; Flanagan, Fidema L; Fenlon, Helen M; McNicholas, Michelle M
2009-02-01
To assesses consensus review of discordant screening mammography findings in terms of its sensitivity, safety, and effect on overall performance in the first 6 years of operation of the Irish National Breast Screening Program (NBSP). Women who participated in the Irish NBSP gave written informed consent for use of their data for auditing purposes. Local ethics committee approval was obtained. The study population consisted of women who participated in the Irish NBSP and underwent initial screening mammography at one of the two screening centers serving the eastern part of Ireland between 2000 and 2005. Independent double reading of mammograms was performed. When the readers disagreed regarding referral, the case was reviewed by a consensus panel. Of the 128 569 screenings performed, 1335 (1%) were discussed by consensus. Of the 1335 cases discussed by consensus, 606 (45.39%) were recalled for further assessment. This resulted in an overall recall rate of 4.41%. In those recalled to assessment, 71 cases of malignant disease were diagnosed (ductal carcinoma in situ, n = 24; invasive cancer, n = 47). The remaining 729 patients were returned to biennial screening. Of these 729 patients, seven had false-negative findings that were identified in the subsequent screening round. Use of the highest reader recall method, in which a patient is recalled if her findings are deemed abnormal by either reader, could potentially increase the cancer detection rate by 0.6 per 1000 women screened but would increase the recall rate by 12.69% and the number of false-positive findings by 15.37%. The consensus panel identified 71 (7.33%) of 968 cancers diagnosed. Consensus review substantially reduced the number of cases recalled and was associated with a low false-negative rate.
Negative symptom domain prevalence across diagnostic boundaries: The relevance of diagnostic shifts.
Lyne, John; Renwick, Laoise; O'Donoghue, Brian; Kinsella, Anthony; Malone, Kevin; Turner, Niall; O'Callaghan, Eadbhard; Clarke, Mary
2015-08-30
Negative symptoms are included in diagnostic manuals as part of criteria for schizophrenia spectrum psychoses only, however some studies have found their presence in other diagnoses. This study sought to clarify negative symptom domain prevalence across diagnostic categories, while investigating whether negative symptoms predicted diagnostic shift over time. Scale for the Assessment of Negative Symptoms (SANS) data were collected at first presentation in 197 individuals presenting with first episode psychosis and again at one year follow-up assessment. Negative symptoms were highest among individuals with schizophrenia and among those whose diagnosis shifted from non-schizophrenia spectrum at baseline to schizophrenia spectrum at follow-up. In a non-schizophrenia spectrum group negative symptoms at baseline were not a significant predictor of diagnostic shift to schizophrenia spectrum diagnoses. The study suggests negative symptoms can present among individuals with non-schizophrenia spectrum diagnoses, although this is most relevant for individuals following diagnostic shift from non-schizophrenia spectrum to schizophrenia spectrum diagnoses. The findings support introduction of a negative symptom dimension when describing a range of psychotic illnesses, and indicate that further research investigating the evolution of negative symptoms in non-schizophrenia diagnoses is needed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
[Sequential monitoring of renal transplant with aspiration cytology].
Manfro, R C; Gonçalves, L F; de Moura, L A
1998-01-01
To evaluate the utility of kidney aspiration cytology in the sequential monitorization of acute rejection in renal transplant patients. Thirty patients were submitted to 376 aspirations. The clinical diagnoses were independently established. The representativity of the samples reached 82.7%. The total corrected increment index and the number of immunoactivated cells were higher during acute rejection as compared to normal allograft function, acute tubular necrosis, and cyclosporine nephrotoxicity. The parameters to the diagnosis of acute rejection were sensitivity: 71.8%, specificity: 87.3%, positive predictive value: 50.9%, negative predictive value: 94.9% and accuracy 84.9%. The false positive results were mainly related to cytomegalovirus infection or to the administration of OKT3. In 10 out of 11 false negative results incipient immunoactivation was present alerting to the possibility of acute rejection. Kidney aspiration cytology is a useful tool for the sequential monitorization of acute rejection in renal transplant patients. The best results are reached when the results of aspiration cytology are analyzed with the clinical data.
Screening for acute HIV infection in South Africa: finding acute and chronic disease
Bassett, Ingrid V.; Chetty, Senica; Giddy, Janet; Reddy, Shabashini; Bishop, Karen; Lu, Zhigang; Losina, Elena; Freedberg, Kenneth A.; Walensky, Rochelle P.
2010-01-01
Background The yield of screening for acute HIV infection among general medical patients in resource-scarce settings remains unclear. Our objective was to evaluate a strategy of pooled HIV plasma RNA to diagnose acute HIV infection in patients with negative or discordant rapid HIV antibody tests in Durban, South Africa. Methods We prospectively enrolled patients with negative or discordant rapid HIV antibody tests from a routine HIV screening program in an outpatient department in Durban with an HIV prevalence of 48%. Study participants underwent venipuncture for pooled qualitative HIV RNA, and if positive, quantitative RNA, enzyme immunoassay and Western Blot (WB). Patients with negative or indeterminate WB and positive quantitative HIV RNA were considered acutely infected. Those with chronic infection (positive RNA and WB) despite negative or discordant rapid HIV tests were considered false negative rapid antibody tests. Results Nine hundred ninety-four participants were enrolled with either negative (N=976) or discordant (N=18) rapid test results. Eleven (1.1%, 95% CI: 0.6–2.0%) had acute HIV infection. Of the 994 patients, an additional 20 (2.0%, 95% CI: 1.3–.3.1%) had chronic HIV infection (false negative rapid test). Conclusions One percent of outpatients with negative or discordant rapid HIV tests in Durban, South Africa had acute HIV infection readily detectable through pooled serum HIV RNA screening. Pooled RNA testing also identified an additional 2% of patients with chronic HIV infection. HIV RNA screening has the potential to identify both acute and chronic HIV infections that are otherwise missed by standard HIV testing algorithms. PMID:20553336
Discrimination of plant-parasitic nematodes from complex soil communities using ecometagenetics.
Porazinska, Dorota L; Morgan, Matthew J; Gaspar, John M; Court, Leon N; Hardy, Christopher M; Hodda, Mike
2014-07-01
Many plant pathogens are microscopic, cryptic, and difficult to diagnose. The new approach of ecometagenetics, involving ultrasequencing, bioinformatics, and biostatistics, has the potential to improve diagnoses of plant pathogens such as nematodes from the complex mixtures found in many agricultural and biosecurity situations. We tested this approach on a gradient of complexity ranging from a few individuals from a few species of known nematode pathogens in a relatively defined substrate to a complex and poorly known suite of nematode pathogens in a complex forest soil, including its associated biota of unknown protists, fungi, and other microscopic eukaryotes. We added three known but contrasting species (Pratylenchus neglectus, the closely related P. thornei, and Heterodera avenae) to half the set of substrates, leaving the other half without them. We then tested whether all nematode pathogens-known and unknown, indigenous, and experimentally added-were detected consistently present or absent. We always detected the Pratylenchus spp. correctly and with the number of sequence reads proportional to the numbers added. However, a single cyst of H. avenae was only identified approximately half the time it was present. Other plant-parasitic nematodes and nematodes from other trophic groups were detected well but other eukaryotes were detected less consistently. DNA sampling errors or informatic errors or both were involved in misidentification of H. avenae; however, the proportions of each varied in the different bioinformatic pipelines and with different parameters used. To a large extent, false-positive and false-negative errors were complementary: pipelines and parameters with the highest false-positive rates had the lowest false-negative rates and vice versa. Sources of error identified included assumptions in the bioinformatic pipelines, slight differences in primer regions, the number of sequence reads regarded as the minimum threshold for inclusion in analysis, and inaccessible DNA in resistant life stages. Identification of the sources of error allows us to suggest ways to improve identification using ecometagenetics.
Hashikita, Giichi; Yamaguti, Toshiyuki; Tachi, Yoshimi; Kishi, Etsuko; Kawamura, Toru; Takahashi, Shun; Arai, Yukie; Koyama, Sachie; Huruhata, Toshihumi; Itabashi, Akira; Oka, Yoko; Yamazaki, Tsutomu; Maesaki, Sigefumi
2005-01-01
We investigated the usefullness of Binax NOW urine antigen test, an immunochromatographic assay that binds any soluble Streptococcus pneumoniae antigen (C polysaccharide) for the diagnosis of penumoniae form September 2003 to March 2005. We used 372 samples form the patinets with pneumoniae diagnosed for blood or sputum cultuter or gram-stained sputum smear. Out of 24 culture positive specimens, Binax NOW urine antigen test, showed positive in 18 (75%) specimens. The sensitivity of sputum and blood culture was 71.7% and 83.3%, respectively. Binax NOW urine antigen test was seemed false positives in 55 samples, false negatives in 6 samples. The specificity of Binax NOW urine antigen test was evaluated 84.1%. Overall agreement among tests was 83.6%. When compared to culture, false negative urine antigen may be the result of colonizing S. pneumoniae in sputum or pneumonia caused by an agent other than S. pneumoniae. CRP values for cases were both urine antigen and culture were positive ranged from 40 mg/dl to 10 mg/dl while urine antigen and culture negative cases were predominantly less than 10 mg/dl. Positive blood and pleural fluid culture cases were consistently associated with strongly positive urine antigen tests. Non-agreement between urine antigen, culture, and microscopy may be the result of specimen quality, labile nature of S. pneumoniae and antimicrobial therapy.
Shashi, Vandana; Schoch, Kelly; Spillmann, Rebecca; Cope, Heidi; Tan, Queenie K-G; Walley, Nicole; Pena, Loren; McConkie-Rosell, Allyn; Jiang, Yong-Hui; Stong, Nicholas; Need, Anna C; Goldstein, David B
2018-06-15
Sixty to seventy-five percent of individuals with rare and undiagnosed phenotypes remain undiagnosed after exome sequencing (ES). With standard ES reanalysis resolving 10-15% of the ES negatives, further approaches are necessary to maximize diagnoses in these individuals. In 38 ES negative patients an individualized genomic-phenotypic approach was employed utilizing (1) phenotyping; (2) reanalyses of FASTQ files, with innovative bioinformatics; (3) targeted molecular testing; (4) genome sequencing (GS); and (5) conferring of clinical diagnoses when pathognomonic clinical findings occurred. Certain and highly likely diagnoses were made in 18/38 (47%) individuals, including identifying two new developmental disorders. The majority of diagnoses (>70%) were due to our bioinformatics, phenotyping, and targeted testing identifying variants that were undetected or not prioritized on prior ES. GS diagnosed 3/18 individuals with structural variants not amenable to ES. Additionally, tentative diagnoses were made in 3 (8%), and in 5 individuals (13%) candidate genes were identified. Overall, diagnoses/potential leads were identified in 26/38 (68%). Our comprehensive approach to ES negatives maximizes the ES and clinical data for both diagnoses and candidate gene identification, without GS in the majority. This iterative approach is cost-effective and is pertinent to the current conundrum of ES negatives.
Cole, Laurence A; Khanlian, Sarah A
2004-05-01
False-positive hCG results can lead to erroneous diagnoses and needless chemotherapy and surgery. In the last 2 years, eight publications described cases involving false-positive hCG tests; all eight involved the AxSym test. We investigated the source of this abundance of cases and a simple fix that may be used by clinical laboratories. False-positive hCG was primarily identified by absence of hCG in urine and varying or negative hCG results in alternative tests. Seventeen false-positive serum samples in the AxSym test were evaluated undiluted and at twofold dilution with diluent containing excess goat serum or immunoglobulin. We identified 58 patients with false-positive hCG, 47 of 58 due to the Abbott AxSym total hCGbeta test (81%). Sixteen of 17 of these "false-positive" results (mean 100 mIU/ml) became undetectable when tested again after twofold dilution. A simple twofold dilution with this diluent containing excess goat serum or immunoglobulin completely protected 16 of 17 samples from patients having false-positive results. It is recommended that laboratories using this test use twofold dilution as a minimum to prevent false-positive results.
Nandipati, Kalyana C; Allamaneni, Shyam; Kakarla, Ravindra; Wong, Alfredo; Richards, Neil; Satterfield, James; Turner, James W; Sung, Kae-Jae
2011-05-01
Early identification of pneumothorax is crucial to reduce the mortality in critically injured patients. The objective of our study is to investigate the utility of surgeon performed extended focused assessment with sonography for trauma (EFAST) in the diagnosis of pneumothorax. We prospectively analysed 204 trauma patients in our level I trauma center over a period of 12 (06/2007-05/2008) months in whom EFAST was performed. The patients' demographics, type of injury, clinical examination findings (decreased air entry), CXR, EFAST and CT scan findings were entered into the data base. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated. Of 204 patients (mean age--43.01+/-19.5 years, sex--male 152, female 52) 21 (10.3%) patients had pneumothorax. Of 21 patients who had pneumothorax 12 were due to blunt trauma and 9 were due to penetrating trauma. The diagnosis of pneumothorax in 204 patients demonstrated the following: clinical examination was positive in 17 patients (true positive in 13/21, 62%; 4 were false positive and 8 were false negative), CXR was positive in 16 (true positive in 15/19, 79%; 1 false positive, 4 missed and 2 CXR not performed before chest tube) patients and EFAST was positive in 21 patients (20 were true positive [95.2%], 1 false positive and 1 false negative). In diagnosing pneumothorax EFAST has significantly higher sensitivity compared to the CXR (P=0.02). Surgeon performed trauma room extended FAST is simple and has higher sensitivity compared to the chest X-ray and clinical examination in detecting pneumothorax. Published by Elsevier Ltd.
Does CT help in predicting preepiglottic space invasion in laryngeal carcinoma?
Bozkurt, Gülpembe; Ünsal, Özlem; Çelebi, İrfan; Ayhan, Burak; Guliyev, Umman; Akova, Pınar; Başak, Tülay; Coşkun, Berna Uslu
2018-06-01
Evaluating preepiglottic space involvement in laryngeal cancer by CT may lead misinterpretation. We sought to understand the causes of misinterpretation in evaluating the preepiglottic space by CT and assessed the effects of misinterpretation in treatment plans of patients with laryngeal squamous cell carcinomas. Specimen histopathology reports of 102 (99 male, 3 female) patients who underwent total or partial laryngectomy due to supraglottic and/or transglottic laryngeal carcinoma were reviewed. Neck CTs were also re-assessed for preepiglottic space involvement by three radiologists. The initial surgical treatment choices were re-examined according to the current radiological evaluation in combination with pathological results of the specimens and physical examination findings in the patients. Interobserver agreement regarding image interpretation was based on a kappa analysis. The interclass correlation coefficient in predicting preepiglottic space invasion was 0.74; this was considered 'good.' Among the three radiologists, sensitivity, specificity, accuracy of CT in detecting preepiglottic space involvement were 86-93%, 75-93%, and 77-93%, respectively, while the negative and positive predictive values were 97-98% and 38-50%, respectively. Given the previous treatments applied, false-positive diagnoses for PES involvement resulted in overtreatment in 2.9% of cases. False-negative diagnoses of PES involvement (1.9% of cases) did not result in any undertreatment. Although CT is a practical and inexpensive imaging tool for evaluating laryngeal carcinomas, the PPV of CT in assessing preepiglottic space invasion, especially in advanced tumors, is low and may lead to overtreatment. Copyright © 2017 Elsevier B.V. All rights reserved.
Diagnostic accuracy of an ultrasonic multiple transducer cardiac imaging system
NASA Technical Reports Server (NTRS)
Popp, R. L.; Brown, O. R.; Harrison, D. C.
1975-01-01
An ultrasonic multiple-transducer imaging system for intracardiac structure visualization is developed in order to simplify visualization of the human heart in vivo without radiation hazard or invasion of the body. Results of the evaluation of the diagnostic accuracy of the devised system in a clinical setting for adult patients are presented and discussed. Criteria are presented for recognition of mitral valva prolapse, mitral stenosis, pericardial effusion, atrial septal defect, and left ventricular dyssynergy. The probable cause for false-positive and false-negative diagnoses is discussed. However, hypertrophic myopathy and congestive myopathy were unable to be detected. Since only qualitative criteria were used, it was not possible to differentiate patients with left ventricular volume overload from patients without cardiac pathology.
Ran, Li; Zhao, Wenli; Zhao, Ye; Bu, Huaien
2017-07-01
Contrast-enhanced ultrasound (CEUS) is considered a novel method for diagnosing pancreatic cancer, but currently, there is no conclusive evidence of its accuracy. Using CEUS in discriminating between pancreatic carcinoma and other pancreatic lesions, we aimed to evaluate the diagnostic accuracy of CEUS in predicting pancreatic tumours. Relevant studies were selected from the PubMed, Cochrane Library, Elsevier, CNKI, VIP, and WANFANG databases dating from January 2006 to May 2017. The following terms were used as keywords: "pancreatic cancer" OR "pancreatic carcinoma," "contrast-enhanced ultrasonography" OR "contrast-enhanced ultrasound" OR "CEUS," and "diagnosis." The selection criteria are as follows: pancreatic carcinomas diagnosed by CEUS while the main reference standard was surgical pathology or biopsy (if it involved a clinical diagnosis, particular criteria emphasized); SonoVue or Levovist was the contrast agent; true positive, false positive, false negative, and true negative rates were obtained or calculated to construct the 2 × 2 contingency table; English or Chinese articles; at least 20 patients were enrolled in each group. The Quality Assessment for Studies of Diagnostic Accuracy was employed to evaluate the quality of articles. Pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, summary receiver-operating characteristic curves, and the area under curve were evaluated to estimate the overall diagnostic efficiency. Pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio with 95% confidence intervals (CIs) were calculated with fixed-effect models. Eight of 184 records were eligible for a meta-analysis after independent scrutinization by 2 reviewers. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratios were 0.86 (95% CI 0.81-0.90), 0.75 (95% CI 0.68-0.82), 3.56 (95% CI 2.64-4.78), 0.19 (95% CI 0.13-0.27), and 22.260 (95% CI 8.980-55.177), respectively. The area under the SROC curve was 0.9088. CEUS has a satisfying pooled sensitivity and specificity for discriminating pancreatic cancer from other pancreatic lesions.
David, Solange Gonçalves; Lovero, Kathryn L; Pombo March, Maria de Fátima B; Abreu, Thalita G; Ruffino Netto, Antonio; Kritski, Afranio L; Sant'Anna, Clemax C
2017-06-01
The diagnosis of pediatric tuberculosis (TB) presents many challenges, and is further complicated in HIV-infected patients. While many diagnostic systems have been proposed, there is no pediatric TB diagnosis gold standard. The outcomes of four TB diagnostic systems in HIV-infected children were compared in this study. A retrospective cohort study was conducted at a TB/HIV reference hospital in Rio de Janeiro. HIV-infected pediatric patients evaluated for TB from 1998 to 2010 were reassessed using four diagnostic systems: Kenneth Jones, 1969; Tidjani, 1986; Ben Marais, 2006; Brazilian Ministry of Health, 2010. Results were compared to standardized diagnoses made by an expert panel of physicians. Of the 121 patients in the study cohort, the expert panel diagnosed 64 as TB and 57 as not TB cases. The Tidjani system showed the highest diagnostic accuracy, with and without the inclusion of microbiological data. The Tidjani and Kenneth Jones systems produced fewer false-positives, and the Ben Marais and Ministry of Health fewer false-negatives. Across systems, there was little agreement between TB diagnoses. In HIV-infected pediatric patients, the Ben Marais and Ministry of Health systems are useful for TB diagnostic screening, whereas the Tidjani and Kenneth Jones systems are best used in a reference center setting. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Interval cancers in a population-based screening program for colorectal cancer in catalonia, Spain.
Garcia, M; Domènech, X; Vidal, C; Torné, E; Milà, N; Binefa, G; Benito, L; Moreno, V
2015-01-01
Objective. To analyze interval cancers among participants in a screening program for colorectal cancer (CRC) during four screening rounds. Methods. The study population consisted of participants of a fecal occult blood test-based screening program from February 2000 to September 2010, with a 30-month follow-up (n = 30,480). We used hospital administration data to identify CRC. An interval cancer was defined as an invasive cancer diagnosed within 30 months of a negative screening result and before the next recommended examination. Gender, age, stage, and site distribution of interval cancers were compared with those in the screen-detected group. Results. Within the study period, 97 tumors were screen-detected and 74 tumors were diagnosed after a negative screening. In addition, 17 CRC (18.3%) were found after an inconclusive result and 2 cases were diagnosed within the surveillance interval (2.1%). There was an increase of interval cancers over the four rounds (from 32.4% to 46.0%). When compared with screen-detected cancers, interval cancers were found predominantly in the rectum (OR: 3.66; 95% CI: 1.51-8.88) and at more advanced stages (P = 0.025). Conclusion. There are large numbers of cancer that are not detected through fecal occult blood test-based screening. The low sensitivity should be emphasized to ensure that individuals with symptoms are not falsely reassured.
Clinical Relevance of ASC-H Cytologies: Experience in a Single Tertiary Hospital.
Díaz Del Arco, Cristina; Sanabria Montoro, M Carmen; García López, Dolores; Rodríguez Escudero, Eva; Fernández Aceñero, M Jesús
2016-01-01
To review the cases of atypical squamous cells (ASC), cannot exclude squamous intraepithelial lesion (ASC-H) diagnosed at a single institution and to discuss the interpretation challenges and clinical management of these cases. The ASC-H cases diagnosed at our institution from 2006 to 2015 were studied retrospectively; of 159,000 Pap smears, there were 959 cases of ASC of undetermined significance (ASC-US) and 148 cases of ASC-H. We have reviewed the clinical records of the ASC-H cases, and data have been analyzed using SPSS 20.0. Median age was 43.1 years; 49.6% of the patients had previous cervical cytologies, and 55.9% of them were negative. Following ASC-H diagnosis, another smear was obtained in 97.1% of the cases and in 67.6% a biopsy was performed. Biopsy revealed low-grade dysplasia in 18.8% of the cases, high-grade dysplasia in 27.8%, and infiltrating carcinoma in 2.3%. Patients with significant lesions in histology were younger than patients with negative results (p = 0.08). A diagnosis of ASC-H/squamous intraepithelial lesion in the repeated cytology had a sensitivity of 74.2%, specificity of 39.6%, positive predictive value of 44.8%, and negative predictive value of 70% for the diagnosis of dysplasia. ASC-H diagnosis is associated with a high incidence of histological high-grade lesions. A repeat cytology can aid in the selection of high-risk patients, but there may be false-negative results. © 2016 S. Karger AG, Basel.
Angiography in gastrointestinal bleeding in children
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meyerovitz, M.F.; Fellows, K.E.
1984-10-01
Twenty-seven children aged 1 day to 16 years studied arteriographically for acute or chronic gastrointestinal bleeding were reviewed. Children with known esophageal varices and portal hypertension were excluded. Final diagnoses were made in 25 patients by means of surgery, endoscopy, biopsy, laboratory data, and clinical follow-up. Of these 25 cases, arteriography gave a correct diagnosis in 64% and was falsely negative in 36%. The common causes of bleeding in this study were gastric and duodenal ulcers, gastritis, vascular malformations, and typhlitis. Transcatheter therapy was attempted in six acute bleeders, with success in three (50%).
Risk of breast cancer after false-positive results in mammographic screening.
Román, Marta; Castells, Xavier; Hofvind, Solveig; von Euler-Chelpin, My
2016-06-01
Women with false-positive results are commonly referred back to routine screening. Questions remain regarding their long-term outcome of breast cancer. We assessed the risk of screen-detected breast cancer in women with false-positive results. We conducted a joint analysis using individual level data from the population-based screening programs in Copenhagen and Funen in Denmark, Norway, and Spain. Overall, 150,383 screened women from Denmark (1991-2008), 612,138 from Norway (1996-2010), and 1,172,572 from Spain (1990-2006) were included. Poisson regression was used to estimate the relative risk (RR) of screen-detected cancer for women with false-positive versus negative results. We analyzed information from 1,935,093 women 50-69 years who underwent 6,094,515 screening exams. During an average 5.8 years of follow-up, 230,609 (11.9%) women received a false-positive result and 27,849 (1.4%) were diagnosed with screen-detected cancer. The adjusted RR of screen-detected cancer after a false-positive result was 2.01 (95% CI: 1.93-2.09). Women who tested false-positive at first screen had a RR of 1.86 (95% CI: 1.77-1.96), whereas those who tested false-positive at third screening had a RR of 2.42 (95% CI: 2.21-2.64). The RR of breast cancer at the screening test after the false-positive result was 3.95 (95% CI: 3.71-4.21), whereas it decreased to 1.25 (95% CI: 1.17-1.34) three or more screens after the false-positive result. Women with false-positive results had a twofold risk of screen-detected breast cancer compared to women with negative tests. The risk remained significantly higher three or more screens after the false-positive result. The increased risk should be considered when discussing stratified screening strategies. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.
Grogan, Eric L; Deppen, Stephen A; Ballman, Karla V; Andrade, Gabriela M; Verdial, Francys C; Aldrich, Melinda C; Chen, Chiu L; Decker, Paul A; Harpole, David H; Cerfolio, Robert J; Keenan, Robert J; Jones, David R; D'Amico, Thomas A; Shrager, Joseph B; Meyers, Bryan F; Putnam, Joe B
2014-04-01
Fluorodeoxyglucose-positron emission tomography (FDG-PET) is recommended for diagnosis and staging of non-small cell lung cancer (NSCLC). Meta-analyses of FDG-PET diagnostic accuracy demonstrated sensitivity of 96% and specificity of 78% but were performed in select centers, introducing potential bias. This study evaluates the accuracy of FDG-PET to diagnose NSCLC and examines differences across enrolling sites in the national American College of Surgeons Oncology Group (ACOSOG) Z4031 trial. Between 2004 and 2006, 959 eligible patients with clinical stage I (cT1-2 N0 M0) known or suspected NSCLC were enrolled in the Z4031 trial, and with a baseline FDG-PET available for 682. Final diagnosis was determined by pathologic examination. FDG-PET avidity was categorized into avid or not avid by radiologist description or reported maximum standard uptake value. FDG-PET diagnostic accuracy was calculated for the entire cohort. Accuracy differences based on preoperative size and by enrolling site were examined. Preoperative FDG-PET results were available for 682 participants enrolled at 51 sites in 39 cities. Lung cancer prevalence was 83%. FDG-PET sensitivity was 82% (95% confidence interval, 79 to 85) and specificity was 31% (95% confidence interval, 23% to 40%). Positive and negative predictive values were 85% and 26%, respectively. Accuracy improved with lesion size. Of 80 false-positive scans, 69% were granulomas. False-negative scans occurred in 101 patients, with adenocarcinoma being the most frequent (64%), and 11 were 10 mm or less. The sensitivity varied from 68% to 91% (p=0.03), and the specificity ranged from 15% to 44% (p=0.72) across cities with more than 25 participants. In a national surgical population with clinical stage I NSCLC, FDG-PET to diagnose lung cancer performed poorly compared with published studies. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Gubern-Mérida, Albert; Vreemann, Suzan; Martí, Robert; Melendez, Jaime; Lardenoije, Susanne; Mann, Ritse M; Karssemeijer, Nico; Platel, Bram
2016-02-01
To evaluate the performance of an automated computer-aided detection (CAD) system to detect breast cancers that were overlooked or misinterpreted in a breast MRI screening program for women at increased risk. We identified 40 patients that were diagnosed with breast cancer in MRI and had a prior MRI examination reported as negative available. In these prior examinations, 24 lesions could retrospectively be identified by two breast radiologists in consensus: 11 were scored as visible and 13 as minimally visible. Additionally, 120 normal scans were collected from 120 women without history of breast cancer or breast surgery participating in the same MRI screening program. A fully automated CAD system was applied to this dataset to detect malignant lesions. At 4 false-positives per normal case, the sensitivity for the detection of cancer lesions that were visible or minimally visible in retrospect in prior-negative examinations was 0.71 (95% CI=0.38-1.00) and 0.31 (0.07-0.59), respectively. A substantial proportion of cancers that were misinterpreted or overlooked in an MRI screening program was detected by a CAD system in prior-negative examinations. It has to be clarified with further studies if such a CAD system has an influence on the number of misinterpreted and overlooked cancers in clinical practice when results are given to a radiologist. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Neonatal respiratory distress syndrome: Chest X-ray or lung ultrasound? A systematic review
Culpan, Anne-Marie; Watts, Catriona; Munyombwe, Theresa; Wolstenhulme, Stephen
2017-01-01
Background and aim Neonatal respiratory distress syndrome is a leading cause of morbidity in preterm new-born babies (<37 weeks gestation age). The current diagnostic reference standard includes clinical testing and chest radiography with associated exposure to ionising radiation. The aim of this review was to compare the diagnostic accuracy of lung ultrasound against the reference standard in symptomatic neonates of ≤42 weeks gestation age. Methods A systematic search of literature published between 1990 and 2016 identified 803 potentially relevant studies. Six studies met the review inclusion criteria and were retrieved for analysis. Quality assessment was performed before data extraction and meta-analysis. Results Four prospective cohort studies and two case control studies included 480 neonates. All studies were of moderate methodological quality although heterogeneity was evident across the studies. The pooled sensitivity and specificity of lung ultrasound were 97% (95% confidence interval [CI] 94–99%) and 91% (CI: 86–95%) respectively. False positive diagnoses were made in 16 cases due to pneumonia (n = 8), transient tachypnoea (n = 3), pneumothorax (n = 1) and meconium aspiration syndrome (n = 1); the diagnoses of the remaining three false positive results were not specified. False negatives diagnoses occurred in nine cases, only two were specified as air-leak syndromes. Conclusions Lung ultrasound was highly sensitive for the detection of neonatal respiratory distress syndrome although there is potential to miss co-morbid air-leak syndromes. Further research into lung ultrasound diagnostic accuracy for neonatal air-leak syndrome and economic modelling for service integration is required before lung ultrasound can replace chest radiography as the imaging component of the reference standard. PMID:28567102
Patel, Bhavika K; Naylor, Michelle E; Kosiorek, Heidi E; Lopez-Alvarez, Yania M; Miller, Adrian M; Pizzitola, Victor J; Pockaj, Barbara A
Supplement tomosynthesis-detected architectural distortions (AD) with CESM to better characterize malignant vs benign lesions. Retrospective review CESM prior to biopsied AD. Pathology: benign, radial scar, or malignant. 49 lesions (45 patients). 29 invasive cancers, 1 DCIS (range, 0.4-4.7cm); 9 radial scars; 10 benign. 37 (75.5%) ADs had associated enhancement. PPV 78.4% (29/37), sensitivity 96.7% (29/30); specificity, 57.9% (11/19); NPV, 91.7% (11/12). False-positive rate 21.6% (8/37); false-negative rate, 8.3% (1/12). Accuracy 81.6% (40/49). High sensitivity and NPV of CESM in patients with AD is promising as an adjunct tool in diagnosing malignancy and avoiding unnecessary biopsy, respectively. Copyright © 2017 Elsevier Inc. All rights reserved.
Hill, William Allen; Randolph, Mildred M; Mandrell, Timothy D
2009-07-01
We determined the sensitivity of perianal tape impressions to detect Syphacia spp. in rats and mice. We evaluated 300 rat and 200 mouse perianal impressions over 9 wk. Pinworm-positive perianal tape impressions from animals with worm burdens at necropsy were considered as true positives. Conversely, pinworm-negative perianal tape impressions from animals with worm burdens were considered false negatives. The sensitivity of perianal tape impressions for detecting Syphacia muris infections in rats was 100%, and for detecting Syphacia obvelata in mice was 85.5%. Intermittent shedding of Syphacia obvelata ova is the most probable explanation for the decreased sensitivity rate we observed in mice. We urge caution in use of perianal tape impressions alone for Syphacia spp. screening in sentinel mice and rats.
Cystic lesions of the salivary glands: cytologic features in fine-needle aspiration biopsies.
Layfield, Lester J; Gopez, Evelyn V
2002-10-01
A variety of neoplastic and nonneoplastic lesions of the salivary glands have a predominantly cystic architecture. Fine-needle aspirates of these lesions yield watery or mucoid material, frequently of low cellularity. Such aspirates may be obtained from mucus retention cysts, lymphoepithelial cysts, cystadenomas, Warthin's tumors, cystic pleomorphic adenomas, low-grade mucoepidermoid carcinomas, cystadenocarcinomas, and examples of polycystic disease of the parotid gland. The cellular component within the fluid obtained from these lesions may be exceedingly scant or absent, making cytologic diagnosis difficult and, at times, impossible. We studied a series of 56 cystic lesions of the salivary glands, including 38 Warthin's tumors, 6 benign cysts, 2 lymphoepithelial cysts, 5 low-grade mucoepidermoid carcinomas, 1 cystic pleomorphic adenoma, 2 cystadenomas, and 2 cystadenocarcinomas. Careful attention to the cellular elements present often allowed definitive cytologic diagnosis, with an overall accuracy rate of 84%. The presence of atypical squamous metaplasia in oncocytic lesions was a significant cause of false-positive diagnoses of carcinoma (4 cases, 7%). Aspirates of low-grade mucoepidermoid carcinoma may contain no epithelial cells and result in false-negative diagnoses (1 case, 2%). Copyright 2002 Wiley-Liss, Inc.
Green disease in optical coherence tomography diagnosis of glaucoma.
Sayed, Mohamed S; Margolis, Michael; Lee, Richard K
2017-03-01
Optical coherence tomography (OCT) has become an integral component of modern glaucoma practice. Utilizing color codes, OCT analysis has rendered glaucoma diagnosis and follow-up simpler and faster for the busy clinician. However, green labeling of OCT parameters suggesting normal values may confer a false sense of security, potentially leading to missed diagnoses of glaucoma and/or glaucoma progression. Conditions in which OCT color coding may be falsely negative (i.e., green disease) are identified. Early glaucoma in which retinal nerve fiber layer (RNFL) thickness and optic disc parameters, albeit labeled green, are asymmetric in both eyes may result in glaucoma being undetected. Progressively decreasing RNFL thickness may reveal the presence of progressive glaucoma that, because of green labeling, can be missed by the clinician. Other ocular conditions that can increase RNFL thickness can make the diagnosis of coexisting glaucoma difficult. Recently introduced progression analysis features of OCT may help detect green disease. Recognition of green disease is of paramount importance in diagnosing and treating glaucoma. Understanding the limitations of imaging technologies coupled with evaluation of serial OCT analyses, prompt clinical examination, and structure-function correlation is important to avoid missing real glaucoma requiring treatment.
Use of magnetic resonance imaging for the investigation of orbital disease in small animals.
Dennis, R
2000-04-01
Twenty-five small animal patients presenting with signs of orbital disease were investigated using magnetic resonance imaging (MRI) in an attempt to assess the value of this imaging technique for diagnosis. All patients were also examined using ultrasonography, and skull radiography was performed in 20 of these animals. The final diagnoses included neoplasia, inflammatory disease and foreign body penetration. MRI produced detailed images of orbital tissues and provided more information about the extent of pathology than the other imaging techniques; a correct diagnosis based solely on the MRI scan was made in 22 cases. Radiography was found to be helpful only in cases in which neoplastic disease extended markedly beyond the confines of the orbit into the nasal chamber and paranasal sinuses. Radiographic changes other than soft tissue swelling were not evident in other orbital disease processes. Ultrasonography gave both false negative and false positive diagnoses for neoplastic masses, although it allowed the correct diagnosis of both cases of foreign bodies and one of the three cases of retrobulbar abscesses in this series. MRI is recommended for patients in which radiography and ultrasonography fall to produce a confident diagnosis or for which surgery is proposed.
Pina, Géraldine; Dubois, Séverine; Murat, Arnaud; Berger, Nicole; Niccoli, Patricia; Peix, Jean-Louis; Cohen, Régis; Guillausseau, Claudine; Charrie, Anne; Chabre, Olivier; Cornu, Catherine; Borson-Chazot, Françoise; Rohmer, Vincent
2013-03-01
To evaluate a second-generation assay for basal serum calcitonin (CT) measurements compared with the pentagastrin-stimulation test for the diagnosis of inherited medullary thyroid carcinoma (MTC) and the follow-up of patients with MTC after surgery. Recent American Thyroid Association recommendations suggest the use of basal CT alone to diagnose and assess follow-up of MTC as the pentagastrin (Pg) test is unavailable in many countries. Multicentric prospective study. A total of 162 patients with basal CT <10 ng/l were included: 54 asymptomatic patients harboured noncysteine 'rearranged during transfection' (RET) proto-oncogene mutations and 108 patients had entered follow-up of MTC after surgery. All patients underwent basal and Pg-stimulated CT measurements using a second-generation assay with 5-ng/l functional sensitivity. Ninety-five per cent of patients with basal CT ≥ 5 ng/l and 25% of patients with basal CT <5 ng/l had a positive Pg-stimulation test (Pg CT >10 ng/l). Compared with the reference Pg test, basal CT ≥ 5 ng/l had 99% specificity, a 95%-positive predictive value but only 35% sensitivity (P < 0.0001). Overall, there were 31% less false-negative results using a 5-ng/l threshold for basal CT instead of the previously used 10-ng/l threshold. The ultrasensitive CT assay reduces the false-negative rate of basal CT measurements when diagnosing familial MTC and in postoperative follow-up compared with previously used assays. However, its sensitivity to detect C-cell disease remains lower than that of the Pg-stimulation test. © 2012 Blackwell Publishing Ltd.
Development of the 7-Item Binge-Eating Disorder Screener (BEDS-7)
Deal, Linda S.; DiBenedetti, Dana B.; Nelson, Lauren; Fehnel, Sheri E.; Brown, T. Michelle
2016-01-01
Objective Develop a brief, patient-reported screening tool designed to identify individuals with probable binge-eating disorder (BED) for further evaluation or referral to specialists. Methods Items were developed on the basis of the DSM-5 diagnostic criteria, existing tools, and input from 3 clinical experts (January 2014). Items were then refined in cognitive debriefing interviews with participants self-reporting BED characteristics (March 2014) and piloted in a multisite, cross-sectional, prospective, noninterventional study consisting of a semistructured diagnostic interview (to diagnose BED) and administration of the pilot Binge-Eating Disorder Screener (BEDS), Binge Eating Scale (BES), and RAND 36-Item Short-Form Health Survey (RAND-36) (June 2014–July 2014). The sensitivity and specificity of classification algorithms (formed from the pilot BEDS item-level responses) in predicting BED diagnosis were evaluated. The final algorithm was selected to minimize false negatives and false positives, while utilizing the fewest number of BEDS items. Results Starting with the initial BEDS item pool (20 items), the 13-item pilot BEDS resulted from the cognitive debriefing interviews (n = 13). Of the 97 participants in the noninterventional study, 16 were diagnosed with BED (10/62 female, 16%; 6/35 male, 17%). Seven BEDS items (BEDS-7) yielded 100% sensitivity and 38.7% specificity. Participants correctly identified (true positives) had poorer BES scores and RAND-36 scores than participants identified as true negatives. Conclusions Implementation of the brief, patient-reported BEDS-7 in real-world clinical practice is expected to promote better understanding of BED characteristics and help physicians identify patients who may have BED. PMID:27486542
Development of the 7-Item Binge-Eating Disorder Screener (BEDS-7).
Herman, Barry K; Deal, Linda S; DiBenedetti, Dana B; Nelson, Lauren; Fehnel, Sheri E; Brown, T Michelle
2016-01-01
Develop a brief, patient-reported screening tool designed to identify individuals with probable binge-eating disorder (BED) for further evaluation or referral to specialists. Items were developed on the basis of the DSM-5 diagnostic criteria, existing tools, and input from 3 clinical experts (January 2014). Items were then refined in cognitive debriefing interviews with participants self-reporting BED characteristics (March 2014) and piloted in a multisite, cross-sectional, prospective, noninterventional study consisting of a semistructured diagnostic interview (to diagnose BED) and administration of the pilot Binge-Eating Disorder Screener (BEDS), Binge Eating Scale (BES), and RAND 36-Item Short-Form Health Survey (RAND-36) (June 2014-July 2014). The sensitivity and specificity of classification algorithms (formed from the pilot BEDS item-level responses) in predicting BED diagnosis were evaluated. The final algorithm was selected to minimize false negatives and false positives, while utilizing the fewest number of BEDS items. Starting with the initial BEDS item pool (20 items), the 13-item pilot BEDS resulted from the cognitive debriefing interviews (n = 13). Of the 97 participants in the noninterventional study, 16 were diagnosed with BED (10/62 female, 16%; 6/35 male, 17%). Seven BEDS items (BEDS-7) yielded 100% sensitivity and 38.7% specificity. Participants correctly identified (true positives) had poorer BES scores and RAND-36 scores than participants identified as true negatives. Implementation of the brief, patient-reported BEDS-7 in real-world clinical practice is expected to promote better understanding of BED characteristics and help physicians identify patients who may have BED.
Wu, Zhenyu; Qin, Guoyou; Zhao, Naiqing; Jia, Huixun; Zheng, Xueying
2018-05-16
Although a minimum of 12 lymph nodes (LNs) has been recommended for colorectal cancer, there remains considerable debates for rectal cancer patients. Inadequacy of examined LNs would lead to under-staging, and inappropriate treatment as a consequence. We describe statistical tool that allows an estimate the probability of false-negative nodes. A total of 26,778 adenocarcinoma rectum cancer patients with tumour stage (T stage) 1-3, diagnosed between 2004 and 2013, who did not receive neoadjuvant therapies and had at least one histologically assessed LN, were extracted from the Surveillance, Epidemiology and End Results (SEER) database. A statistical tool using beta-binomial distribution was developed to estimate the probability of an occult nodal disease is truly node-negative as a function of total number of LNs examined and T stage. The probability of falsely identifying a patient as node-negative decreased with an increasing number of nodes examined for each stage. It was estimated to be 72%, 66% and 52% for T1, T2 and T3 patients respectively with a single node examined. To confirm an occult nodal disease with 90% confidence, 5, 9, and 29 nodes need to be examined for patients from stages T1, T2, and T3, respectively. The false-negative rate of the examined lymph nodes in rectal cancer was verified to be dependent preoperatively on the clinical tumour stage. A more accurate nodal staging score was developed to recommend a threshold on the minimum number of examined nodes regarding to the favored level of confidence. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Sentinel lymph node detection in patients with early cervical cancer.
Acharya, B C; Jihong, L
2009-01-01
Lymph node status is the most important independent prognostic factor in early stage cervical cancer. Intraoperative lymphatic mapping and sentinel lymph node detection have been increasingly evaluated in the treatment of a variety of solid tumors, particularly breast cancer and cutaneous melanoma. This study evaluated the feasibility of these procedures in patients undergoing radical hysterectomy with pelvic lymphadenectomy for early cervical cancer. A total of 30 patients with histologically diagnosed FIGO stage IA to IIA cervical cancer were enrolled to this study. They were scheduled to undergo radical abdominal hysterectomy and pelvic lymphadenectomy after injecting patent blue dye in cervix. A total of 60 SLNs (mean 2.5) were detected in 24 patients with detection rate of 80%. Bilateral SLNs were detected in 70.1% of cases. SLNs were identified in obturator and external iliac areas in 50% and 31.7%, respectively; no SLNs were discovered in the common iliac region. Seven patients (23.3%) had lymph node metastases; one of these had false negative SLN.The false negative rate and negative predictive value were 14.3% and 94.4%, respectively. SLN detection procedure with blue dye technique is a feasible procedure in cervical cancer. Patent blue dye is cheap, safe and effective tracer to detect sentinel node in carcinoma of cervix.
Storholm, Erik David; Silverberg, Michael J; Satre, Derek D
2016-01-01
Access to substance use disorder (SUD) treatment is a critical issue for women with HIV. This study examined differences in SUD diagnoses, comorbid psychiatric diagnoses, and predictors of SUD treatment initiation among a diverse sample of HIV-positive women (n = 228) and a demographically similar cohort of HIV-negative women (n = 693). Diagnoses and service utilization data were obtained from electronic health records of members of a large integrated healthcare system in Northern California. HIV-positive women were less likely to initiate SUD treatment. Significant racial/ethnic differences were found among both HIV-positive and HIV-negative women with respect to SUD diagnosis type and diagnosis of comorbid psychiatric disorders. Among the HIV-negative women, rates of SUD treatment initiation were lower for black women than for white or Latina women. Multivariable logistic regression models showed that alcohol, cannabis, and opiate diagnoses were predictive of SUD treatment initiation for both cohorts, while amphetamine diagnoses, comorbid depressive disorder, and being white or Latina were predictive of SUD treatment initiation for HIV-negative, but not HIV-positive, women. Findings suggest that clinicians need to be aware of differences in substances of abuse, comorbid psychiatric disorders, and to consider the demographic and social factors that may contribute to differences in SUD treatment initiation among HIV-positive and HIV-negative women.
Jo, Yong Suk; Park, Ju-Hee; Lee, Jung Kyu; Heo, Eun Young; Chung, Hee Soon; Kim, Deog Kyeom
2016-01-01
The prevalence and clinical implications of discordance between Xpert MTB/RIF assays and the AdvanSure TB/NTM real-time polymerase chain reaction (PCR) for bronchial washing specimens have not been studied in pulmonary TB (PTB) patients. The discordant proportion and its clinical impact were evaluated in 320 patients from the bronchoscopy registry whose bronchial washing specimens were tested simultaneously with Xpert MTB/RIF and the TB/NTM PCR assay for three years, and the accuracy of the assays, including the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were studied. The clinical risk factors for discordance and false positivity of assays were also studied. Among 130 patients who were clinically diagnosed with PTB, 64 patients showed positive acid-fast bacilli culture results, 56 patients showed positive results in molecular methods and clinician diagnosed PTB without results of microbiology in 10 patients. The sensitivity, specificity, PPV, and NPV were 80.0%, 98.95%, 98.1%, and 87.9%, respectively, for Xpert MTB/RIF and 81.5%, 92.6%, 88.3%, and 88.0%, respectively, for TB/NTM PCR. The discordant proportion was 16.9% and was higher in culture-negative PTB compared to culture-confirmed PTB (24.3% vs. 9.4%, p = 0.024). However, there were no significant differences in the clinical characteristics, regardless of the discordance. The diagnostic yield increased with an additional assay (7.7% for Xpert MTB/RIF and 9.2% for TB/NTM PCR). False positivity was less common in patients tested with Xpert MTB/RIF (1.05% vs. 7.37%, p = 0.0035). No host-related risk factor for false positivity was identified. The Xpert MTB/RIF and TB/NTM PCR assay in bronchial washing specimens can improve the diagnostic yields for PTB, although there were considerable discordant results without any patient-related risk factors.
Impact on obstetric outcome of third-trimester screening for small-for-gestational-age fetuses.
Callec, R; Lamy, C; Perdriolle-Galet, E; Patte, C; Heude, B; Morel, O
2015-08-01
To evaluate the performance of screening for small-for-gestational-age (SGA) fetuses by ultrasound biometry at 30-35 weeks' gestation, and to determine the impact of screening on obstetric and neonatal outcomes. For this prospective cohort study, pregnant women were recruited from two French university maternity centers between 2003 and 2006. Performance measures of third-trimester biometry for the prediction of SGA, defined as estimated fetal weight < 10(th) centile, were analyzed. Obstetric outcomes and neonatal health status were compared, first, between SGA neonates diagnosed correctly at ultrasound examination (true positive (TP); n = 45) and SGA neonates that went undiagnosed (false negative (FN); n = 110) and, second, between non-SGA neonates identified as normal at ultrasound examination (true negative (TN); n = 1641) and non-SGA neonates diagnosed incorrectly as SGA (false positive (FP); n = 101). In the prediction of SGA, third-trimester ultrasound had a sensitivity of 29.0% (95% CI, 22.5-36.6%) and specificity of 94.2% (95% CI, 93.0-95.2%). Positive and negative predictive values were 30.8% (95% CI, 23.9-38.7%) and 93.7% (95% CI, 92.5-94.8%), respectively. One hundred and ten SGA neonates went undiagnosed at ultrasound. Compared to the TN neonates considered as of normal weight at ultrasound, planned preterm delivery (before 37 weeks) and elective Cesarean section for a fetal growth indication were 2.4 (P = 0.01) and 2.85 (P = 0.003) times more likely to occur, respectively, in the FP group of non-SGA neonates, diagnosed incorrectly as SGA during the antenatal period. There was no statistically significant difference in 5-min Apgar score < 7, cord blood pH at birth < 7.15 and need for neonatal resuscitation between the two subgroups (TN vs FP and TP vs FN). The performance of third-trimester ultrasound screening for SGA seems poor, as it misses the diagnosis of a large number of SGA neonates. The consequences of routine screening for SGA in a low-risk population may lead to unnecessary planned preterm deliveries and elective Cesarean sections in FP pregnancies, without improved neonatal outcome in the FN pregnancies. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.
Weinrich, Julius Matthias; Bannas, Peter; Regier, Marc; Keller, Sarah; Kluth, Luis; Adam, Gerhard; Henes, Frank Oliver
2018-03-01
The purpose of this study is to assess the diagnostic yield of low-dose (LD) CT for alternative diagnoses in patients with suspected urolithiasis. In this retrospective study, we included 776 consecutive patients who underwent unenhanced abdominal CT for evaluation of suspected urolithiasis. All examinations were performed with an LD CT protocol; images were reconstructed using iterative reconstruction. The leading LD CT diagnosis was recorded for each patient and compared with the final clinical diagnosis, which served as the reference standard. The mean (± SD) effective dose of CT was 1.9 ± 0.6 mSv. The frequency of urolithiasis was 82.5% (640/776). LD CT reached a sensitivity of 94.1% (602/640), a specificity of 100.0% (136/136), and an accuracy of 95.1% (738/776) for the detection of urolithiasis. In 93 of 136 patients (68.4%) without urolithiasis, alternative diagnoses were established as the final clinical diagnoses. Alternative diagnoses were most commonly located in the genitourinary (n = 53) and gastrointestinal (n = 18) tracts. LD CT correctly provided alternative diagnoses for 57 patients (61.3%) and was false-negative for five patients (5.4%). The most common clinical alternative diagnoses were urinary tract infections (n = 22). Seven diagnoses missed at LD CT were located outside the FOV. For 43 of all 776 patients (5.5%), neither LD CT nor clinical workup could establish a final diagnosis. The sensitivity, specificity, and accuracy of LD CT for the detection of alternative diagnoses were 91.9% (57/62), 95.6% (43/45), and 93.5% (100/107), respectively. LD CT enables the diagnosis of most alternative diagnoses in the setting of suspected urolithiasis. The most frequent alternative diagnoses missed by LD CT are urinary tract infections or diagnoses located outside the FOV of the abdominopelvic CT scan.
Zheng, S; Lin, R J; Chan, Y H; Ngan, C C L
2018-03-01
There is no clear consensus on the diagnosis of neurosyphilis. The Venereal Disease Research Laboratory (VDRL) test from cerebrospinal fluid (CSF) has traditionally been considered the gold standard for diagnosing neurosyphilis but is widely known to be insensitive. In this study, we compared the clinical and laboratory characteristics of true-positive VDRL-CSF cases with biological false-positive VDRL-CSF cases. We retrospectively identified cases of true and false-positive VDRL-CSF across a 3-year period received by the Immunology and Serology Laboratory, Singapore General Hospital. A biological false-positive VDRL-CSF is defined as a reactive VDRL-CSF with a non-reactive Treponema pallidum particle agglutination (TPPA)-CSF and/or negative Line Immuno Assay (LIA)-CSF IgG. A true-positive VDRL-CSF is a reactive VDRL-CSF with a concordant reactive TPPA-CSF and/or positive LIA-CSF IgG. During the study period, a total of 1254 specimens underwent VDRL-CSF examination. Amongst these, 60 specimens from 53 patients tested positive for VDRL-CSF. Of the 53 patients, 42 (79.2%) were true-positive cases and 11 (20.8%) were false-positive cases. In our setting, a positive non-treponemal serology has 97.6% sensitivity, 100% specificity, 100% positive predictive value and 91.7% negative predictive value for a true-positive VDRL-CSF based on our laboratory definition. HIV seropositivity was an independent predictor of a true-positive VDRL-CSF. Biological false-positive VDRL-CSF is common in a setting where patients are tested without first establishing a serological diagnosis of syphilis. Serological testing should be performed prior to CSF evaluation for neurosyphilis. © 2017 European Academy of Dermatology and Venereology.
An investigation into false-negative transthoracic fine needle aspiration and core biopsy specimens.
Minot, Douglas M; Gilman, Elizabeth A; Aubry, Marie-Christine; Voss, Jesse S; Van Epps, Sarah G; Tuve, Delores J; Sciallis, Andrew P; Henry, Michael R; Salomao, Diva R; Lee, Peter; Carlson, Stephanie K; Clayton, Amy C
2014-12-01
Transthoracic fine needle aspiration (TFNA)/core needle biopsy (CNB) under computed tomography (CT) guidance has proved useful in the assessment of pulmonary nodules. We sought to determine the TFNA false-negative (FN) rate at our institution and identify potential causes of FN diagnoses. Medical records were reviewed from 1,043 consecutive patients who underwent CT-guided TFNA with or without CNB of lung nodules over a 5-year time period (2003-2007). Thirty-seven FN cases of "negative" TFNA/CNB with malignant outcome were identified with 36 cases available for review, of which 35 had a corresponding CNB. Cases were reviewed independently (blinded to original diagnosis) by three pathologists with 15 age- and sex-matched positive and negative controls. Diagnosis (i.e., nondiagnostic, negative or positive for malignancy, atypical or suspicious) and qualitative assessments were recorded. Consensus diagnosis was suspicious or positive in 10 (28%) of 36 TFNA cases and suspicious in 1 (3%) of 35 CNB cases, indicating potential interpretive errors. Of the 11 interpretive errors (including both suspicious and positive cases), 8 were adenocarcinomas, 1 squamous cell carcinoma, 1 metastatic renal cell carcinoma, and 1 lymphoma. The remaining 25 FN cases (69.4%) were considered sampling errors and consisted of 7 adenocarcinomas, 3 nonsmall cell carcinomas, 3 lymphomas, 2 squamous cell carcinomas, and 2 renal cell carcinomas. Interpretive and sampling error cases were more likely to abut the pleura, while histopathologically, they tended to be necrotic and air-dried. The overall FN rate in this patient cohort is 3.5% (1.1% interpretive and 2.4% sampling errors). © 2014 Wiley Periodicals, Inc.
Perceptions of academic skills of children diagnosed with ADHD.
Eisenberg, Daniel; Schneider, Helen
2007-05-01
This study investigates how the academic skills of children diagnosed with ADHD are perceived by teachers, parents, and the children themselves. The authors analyze data collected for third graders in spring 2002 in the nationally representative Early Childhood Longitudinal Survey. They use linear regressions to estimate independent associations between perceptions of academic abilities and parent-reported ADHD diagnoses, controlling for scores on standardized reading and math tests, assessments of externalizing behaviors, and other factors. Results show that for ADHD-diagnosed girls compared to other girls, both parents' and teachers' perceptions are substantially more negative. For ADHD-diagnosed boys, the differentials are also negative but less pronounced. Self-perceptions are not significantly different by ADHD status, except for boys' more negative self-perceptions related to math. Given the potentially damaging effects of these negative perceptions and expectations on self-esteem, motivation, and performance, efforts may be needed to bring perceptions of ADHD children more in line with the abilities they demonstrate on objective assessments. (J. of Att. Dis. 2007; 10(4) 390-397).
Assessment of clinical scoring systems for the diagnosis of Williams-Beuren syndrome.
Leme, D E S; Souza, D H; Mercado, G; Pastene, E; Dias, A; Moretti-Ferreira, D
2013-09-04
Williams-Beuren syndrome (WBS) is a genetic disorder characterized by physical and intellectual developmental delay, associated with congenital heart disease and facial dysmorphism. WBS is caused by a microdeletion on chromosome 7 (7q11.23), which encompasses the elastin (ELN) gene and about 27 other genes. The gold standard for WBS laboratory diagnosis is FISH (fluorescence in situ hybridization), which is very costly. As a possible alternative, we investigated the accuracy of three clinical diagnostic scoring systems in 250 patients with WBS diagnosed by FISH. We concluded that all three systems could be used for the clinical diagnosis of WBS, but they all gave a low percentage of false-positive (6.0-9.2%) and false-negative (0.8-4.0%) results. Therefore, their use should be associated with FISH testing.
Skin testing for immediate hypersensitivity to corticosteroids: a case series and literature review.
Baker, A; Empson, M; The, R; Fitzharris, P
2015-03-01
Immediate hypersensitivity to corticosteroids is reported to occur with an incidence of 0.1%. The largest previous case series reporting corticosteroid skin testing has seven patients. We identified 23 patients (mean age 50 years, 65% female) from Auckland City Hospital who underwent skin testing (ST) for suspected corticosteroid hypersensitivity between July 2005 and April 2012. We performed a retrospective clinical case note review detailing clinical history of reaction, skin test results and subsequent management. Most patients (21/23) had a standard panel of testing with prednisolone, triamcinolone, methylprednisolone, hydrocortisone and dexamethasone. Skin tests used a 10% steroid stock concentration for skin prick tests (SPT) and dilutions of 1 : 1000, 1 : 100 and 1 : 10 for subsequent intradermal testing. A weal 3 mm greater than the negative control was considered positive. A total of 23 patients were identified who had skin testing for suspected acute hypersensitivity to corticosteroids, eight of which had a history of anaphylaxis. From 28 reactions (in 23 patients), the most common route of administration was intra-articular (13), followed by oral (7), intravenous (3) and other (5). Skin tests were positive in 8/23 patients, and 7/8 of these patients had a history of corticosteroid-associated anaphylaxis. Skin tests were positive at either the skin prick test or intradermal stages. There was evidence suggesting clinical and skin test cross-reactivity between corticosteroids in one patient. One patient had a positive skin test, but negative oral challenge suggesting the skin test was false positive. Skin tests were negative in 15/23 patients. One patient had a negative prednisolone skin test and positive unblinded oral challenge, suggesting a false-negative skin test. Skin testing can provide sufficient evidence to diagnose allergy in patients with a clear history of immediate hypersensitivity to corticosteroids such as anaphylaxis. Both skin prick and intradermal tests should be used. There is evidence of cross-reactivity between steroids, so a panel is recommended. False-positive and false-negative reactions do occur; however, the frequency is unknown. Challenge remains the only definitive way to demonstrate a safe alternative to use. As the largest case series described, this article provides new evidence for the interpretation of skin tests when investigating possible immediate hypersensitivity to corticosteroids. © 2014 John Wiley & Sons Ltd.
Salzburg Consensus Criteria for Non-Convulsive Status Epilepticus--approach to clinical application.
Leitinger, M; Beniczky, S; Rohracher, A; Gardella, E; Kalss, G; Qerama, E; Höfler, J; Hess Lindberg-Larsen, A; Kuchukhidze, G; Dobesberger, J; Langthaler, P B; Trinka, E
2015-08-01
Salzburg Consensus Criteria for diagnosis of Non-Convulsive Status Epilepticus (SCNC) were proposed at the 4th London-Innsbruck Colloquium on status epilepticus in Salzburg (2013). We retrospectively analyzed the EEGs of 50 consecutive nonhypoxic patients with diagnoses of nonconvulsive status epilepticus (NCSE) at discharge and 50 consecutive controls with abnormal EEGs in a large university hospital in Austria. We implemented the American Clinical Neurophysiology Society's Standardized Critical Care EEG Terminology, 2012 version (ACNS criteria) to increase the test performance of SCNC. In patients without preexisting epileptic encephalopathy, the following criteria were applied: (1) more than 25 epileptiform discharges (ED) per 10-second epoch, i.e., >2.5/s and (2) patients with EDs ≤ 2.5/s or rhythmic delta/theta activity (RDT) exceeding 0.5/s AND at least one of the additional criteria: (2a) clinical and EEG improvements from antiepileptic drugs (AEDs), (2b) subtle clinical phenomena, or (2c) typical spatiotemporal evolution. In case of fluctuation without evolution or EEG improvement without clinical improvement, "possible NCSE" was diagnosed. For identification of RDT, the following criteria were compared: (test condition A) continuous delta-theta activity without further rules, (B) ACNS criterion for rhythmic delta activity (RDA), and (C) ACNS criteria for RDA and fluctuation. False positive rate in controls dropped from 28% (condition A) to 2% (B) (p = 0.00039) and finally to 0% (C) (p = 0.000042). Application of test condition C in the group with NCSE gives one false negative (2%). Various EEG patterns were found in patients with NCSE: (1) 8.2%, (2a) 2%, (2b) 12.2%, and (2c) 32.7%. Possible NCSE was diagnosed based on fluctuations in 57.1% and EEG improvement without clinical improvement in 14.2%. The modified SCNC with refined definitions including the ACNS terminology leads to clinically relevant and statistically significant reduction of false positive diagnoses of NCSE and to minimal loss in sensitivity. This article is part of a Special Issue entitled "Status Epilepticus". Copyright © 2015 Elsevier Inc. All rights reserved.
HIV misdiagnosis in sub-Saharan Africa: performance of diagnostic algorithms at six testing sites
Kosack, Cara S.; Shanks, Leslie; Beelaert, Greet; Benson, Tumwesigye; Savane, Aboubacar; Ng’ang’a, Anne; Andre, Bita; Zahinda, Jean-Paul BN; Fransen, Katrien; Page, Anne-Laure
2017-01-01
Abstract Introduction: We evaluated the diagnostic accuracy of HIV testing algorithms at six programmes in five sub-Saharan African countries. Methods: In this prospective multisite diagnostic evaluation study (Conakry, Guinea; Kitgum, Uganda; Arua, Uganda; Homa Bay, Kenya; Doula, Cameroun and Baraka, Democratic Republic of Congo), samples from clients (greater than equal to five years of age) testing for HIV were collected and compared to a state-of-the-art algorithm from the AIDS reference laboratory at the Institute of Tropical Medicine, Belgium. The reference algorithm consisted of an enzyme-linked immuno-sorbent assay, a line-immunoassay, a single antigen-enzyme immunoassay and a DNA polymerase chain reaction test. Results: Between August 2011 and January 2015, over 14,000 clients were tested for HIV at 6 HIV counselling and testing sites. Of those, 2786 (median age: 30; 38.1% males) were included in the study. Sensitivity of the testing algorithms ranged from 89.5% in Arua to 100% in Douala and Conakry, while specificity ranged from 98.3% in Doula to 100% in Conakry. Overall, 24 (0.9%) clients, and as many as 8 per site (1.7%), were misdiagnosed, with 16 false-positive and 8 false-negative results. Six false-negative specimens were retested with the on-site algorithm on the same sample and were found to be positive. Conversely, 13 false-positive specimens were retested: 8 remained false-positive with the on-site algorithm. Conclusions: The performance of algorithms at several sites failed to meet expectations and thresholds set by the World Health Organization, with unacceptably high rates of false results. Alongside the careful selection of rapid diagnostic tests and the validation of algorithms, strictly observing correct procedures can reduce the risk of false results. In the meantime, to identify false-positive diagnoses at initial testing, patients should be retested upon initiating antiretroviral therapy. PMID:28691437
HIV misdiagnosis in sub-Saharan Africa: performance of diagnostic algorithms at six testing sites.
Kosack, Cara S; Shanks, Leslie; Beelaert, Greet; Benson, Tumwesigye; Savane, Aboubacar; Ng'ang'a, Anne; Andre, Bita; Zahinda, Jean-Paul Bn; Fransen, Katrien; Page, Anne-Laure
2017-07-03
We evaluated the diagnostic accuracy of HIV testing algorithms at six programmes in five sub-Saharan African countries. In this prospective multisite diagnostic evaluation study (Conakry, Guinea; Kitgum, Uganda; Arua, Uganda; Homa Bay, Kenya; Doula, Cameroun and Baraka, Democratic Republic of Congo), samples from clients (greater than equal to five years of age) testing for HIV were collected and compared to a state-of-the-art algorithm from the AIDS reference laboratory at the Institute of Tropical Medicine, Belgium. The reference algorithm consisted of an enzyme-linked immuno-sorbent assay, a line-immunoassay, a single antigen-enzyme immunoassay and a DNA polymerase chain reaction test. Between August 2011 and January 2015, over 14,000 clients were tested for HIV at 6 HIV counselling and testing sites. Of those, 2786 (median age: 30; 38.1% males) were included in the study. Sensitivity of the testing algorithms ranged from 89.5% in Arua to 100% in Douala and Conakry, while specificity ranged from 98.3% in Doula to 100% in Conakry. Overall, 24 (0.9%) clients, and as many as 8 per site (1.7%), were misdiagnosed, with 16 false-positive and 8 false-negative results. Six false-negative specimens were retested with the on-site algorithm on the same sample and were found to be positive. Conversely, 13 false-positive specimens were retested: 8 remained false-positive with the on-site algorithm. The performance of algorithms at several sites failed to meet expectations and thresholds set by the World Health Organization, with unacceptably high rates of false results. Alongside the careful selection of rapid diagnostic tests and the validation of algorithms, strictly observing correct procedures can reduce the risk of false results. In the meantime, to identify false-positive diagnoses at initial testing, patients should be retested upon initiating antiretroviral therapy.
Chacón, Lucía; Mateos, María Luisa; Holguín, África
2017-07-01
Despite the high specificity of fourth-generation enzyme immunoassays (4th-gen-EIA) for screening during HIV diagnosis, their positive predictive value is low in populations with low HIV prevalence. Thus, screening should be optimized to reduce false positive results. The influence of sample cutoff (S/CO) values by a 4th-gen-EIA with the false positive rate during the routine HIV diagnosis in a low HIV prevalence population was evaluated. A total of 30,201 sera were tested for HIV diagnosis using Abbott Architect ® HIV-Ag/Ab-Combo 4th-gen-EIA at a hospital in Spain during 17 months. Architect S/CO values were recorded, comparing the HIV-1 positive results following Architect interpretation (S/CO≥1) with the final HIV-1 diagnosis by confirmatory tests (line immunoassay, LIA and/or nucleic acid test, NAT). ROC curve was also performed. Among the 30,201 HIV performed tests, 256 (0.85%) were positive according to Architect interpretation (S/CO≥1) but only 229 (0.76%) were definitively HIV-1 positive after LIA and/or NAT. Thus, 27 (10.5%) of 256 samples with S/CO≥1 by Architect were false positive diagnose. The false positive rate decreased when the S/CO ratio increased. All 19 samples with S/CO ≤10 were false positives and all 220 with S/CO>50 true HIV-positives. The optimal S/CO cutoff value provided by ROC curves was 32.7. No false negative results were found. We show that very low S/CO values during HIV-1 screening using Architect can result HIV negative after confirmation by LIA and NAT. The false positive rate is reduced when S/CO increases. Copyright © 2017 Elsevier B.V. All rights reserved.
Kowalski, Thomas; Siddiqui, Ali; Loren, David; Mertz, Howard R; Mallat, Damien; Haddad, Nadim; Malhotra, Nidhi; Sadowski, Brett; Lybik, Mark J; Patel, Sandeep N; Okoh, Emuejevoke; Rosenkranz, Laura; Karasik, Michael; Golioto, Michael; Linder, Jeffrey; Catalano, Marc F; Al-Haddad, Mohammad A
2016-09-01
To examine the utility of integrated molecular pathology (IMP) in managing surveillance of pancreatic cysts based on outcomes and analysis of false negatives (FNs) from a previously published cohort (n=492). In endoscopic ultrasound with fine-needle aspiration (EUS-FNA) of cyst fluid lacking malignant cytology, IMP demonstrated better risk stratification for malignancy at approximately 3 years' follow-up than International Consensus Guideline (Fukuoka) 2012 management recommendations in such cases. Patient outcomes and clinical features of Fukuoka and IMP FN cases were reviewed. Practical guidance for appropriate surveillance intervals and surgery decisions using IMP were derived from follow-up data, considering EUS-FNA sampling limitations and high-risk clinical circumstances observed. Surveillance intervals for patients based on IMP predictive value were compared with those of Fukuoka. Outcomes at follow-up for IMP low-risk diagnoses supported surveillance every 2 to 3 years, independent of cyst size, when EUS-FNA sampling limitations or high-risk clinical circumstances were absent. In 10 of 11 patients with FN IMP diagnoses (2% of cohort), EUS-FNA sampling limitations existed; Fukuoka identified high risk in 9 of 11 cases. In 4 of 6 FN cases by Fukuoka (1% of cohort), IMP identified high risk. Overall, 55% of cases had possible sampling limitations and 37% had high-risk clinical circumstances. Outcomes support more cautious management in such cases when using IMP. Adjunct use of IMP can provide evidence for relaxed surveillance of patients with benign cysts that meet Fukuoka criteria for closer observation or surgery. Although infrequent, FN results with IMP can be associated with EUS-FNA sampling limitations or high-risk clinical circumstances.
Reliability of an ELISA test for diagnosing oestrosis in Iberian ibex.
Arias, María Sol; Moreno, Virginia; Sarasa, Mathieu; Paz-Silva, Adolfo; Sánchez-Andrade, Rita; Morrondo, Patrocinio; Díez-Baños, Pablo; Granados, José E; Sánchez, Antonio; Pérez, Jesús M
2014-04-01
Oestrosis is one of the most prevalent parasitosis affecting the Iberian ibex, Capra pyrenaica . To date, both the diagnosis of oestrosis and the determination of the intensity of parasitism require the use of invasive methods (necropsy), which necessarily limit research possibilities. We analyzed the immune humoral response (IgM and IgG) against Oestrus ovis L. excretory/secretory larval antigens in 32 sera taken from Iberian ibex from the Sierra Nevada Natural Space (southern Spain). Three antigens were collected: L1OES (from L1 larvae), L2OES (L2), and L3OES (L3). Necropsy was considered as the gold standard. The percentage of ibexes harboring Oestrus spp. larvae was 88%, the mean intensity of parasitism being 16.96 ± 14.96 larvae per parasitized host (range: 2-52). In our sample, first-instar larvae (L1) were found in 9% of ibexes, while 69% of hosts carried L2 larvae and 88% L3 larvae. Positive correlations between L1 and L2 numbers, and between L2 and L3 numbers were detected. The best results with the immunoenzymatic assay were obtained using IgG antibodies against the L1OES antigens (specificity = 89%; sensitivity = 100%; positive predictive value = 100%; negative predictive value = 57%). The IgG seroprevalence against L1OES was 78%. Thus, the analysis of IgG antibodies against antigens collected from L1 O. ovis larvae would seem to be a noninvasive method for reliably diagnosing oestrosis in naturally infested Iberian ibex. Nevertheless, additional immunological and methodological advances are still required because false positive and false negative results still represent a non-negligible part of the results of the ELISA tests.
Rácil, Z; Kocmanová, I; Wagnerová, B; Winterová, J; Lengerová, M; Moulis, M; Mayer, J
2008-01-01
PREMISES AND OBJECTIVES: Timely diagnosis is of critical importance for the prognosis of invasive aspergilosis (IA) patients. Over recent years, IA detection of galactomannan using the ELISA method has assumed growing importance. The objective of the study was to analyse the usability of the method in current clinical practice of a hemato-oncological ward. From May 2003 to October 2006, blood samples were taken from patients at IA risk to detect galactomannan (GM) in serum using the ELISA method. The patients who underwent the tests were classified by the probability of IA presence on the basis of the results of conventional diagnostic methods and section findings. A total of 11,360 serum samples from 911 adult patients were tested for GM presence. IA (probable/proven) was diagnosed in 42 (4.6%) of them. The rates of sensitivity, specificity, positive and negative predictive value of galactomannan detection for IA diagnosis in our ward were, respectively, 95.2%, 90.0%, 31.5% and 99.7%. The principal causes of the limited positive predictive value of the test were the high percentage of false-positive test results (mainly caused by concomitant administration of some penicillin antibiotics or Plasma-Lyte infusion solution), as well as the fact that a large percentage of patients we examined fell within the group of patients with hematological malignity with a very low prevalence of IA. GM detection in serum is associated with high sensitivity and excellent negative predictive value in IA diagnosis in hemato-oncological patients. Knowledge and elimination of possible causes of false-positive results as well as focusing the screening on patients at greatest risk of infection are necessary for an even better exploitation of the test.
Goyal, Rajen; Zhu, Bing; Parimi, Vamsi; Lin, Xiaoqi; Rohan, Stephen M
2014-07-01
Frozen section (FS) consultation is generally an accurate diagnostic modality. At our institution, we are frequently asked to assess transurethral resection specimens (TURBT) at FS for muscularis propria (MP) invasion by carcinoma. This study documents our experience in evaluating cancer-containing TURBT specimens at FS for MP invasion. 32 TURBT sent for FS from 2008-2010 were identified. The FS and permanent section (PS) diagnoses were reviewed. Cases excluded from the calculation of test performance included: (1) cases without cancer on FS or PS slides, (2) FS diagnosis deferred, (3) cases without MP on FS and subsequent PS slides. Sensitivity (SEN), specificity (SPEC), positive predictive value (PPV), and negative predictive value (NPV) for identifying MP invasion at FS were calculated. In 6 cases, no cancer was present in FS or PS slides (18%). The FS diagnosis was deferred on 3 cases (9%). In one case (3%) MP was not present in the FS or the subsequent PS slides. Of the remaining 22 cases, 2 false positive and 6 false negative diagnoses of MP invasion were identified. The test performance for FS assessment of MP invasion in TURB were SEN=33%, SPEC=84%, PPV=60%, and NPV=64%. Identifying MP invasion on PS can be difficult, and our results suggest that this is more difficult at FS. Though this study is based on small numbers, our results point to the conclusion that examination of TURBT specimens for MP invasion is best done on PS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Handheld echocardiographic screening for rheumatic heart disease by non-experts.
Ploutz, Michelle; Lu, Jimmy C; Scheel, Janet; Webb, Catherine; Ensing, Greg J; Aliku, Twalib; Lwabi, Peter; Sable, Craig; Beaton, Andrea
2016-01-01
Handheld echocardiography (HAND) has good sensitivity and specificity for rheumatic heart disease (RHD) when performed by cardiologists. However, physician shortages in RHD-endemic areas demand less-skilled users to make RHD screening practical. We examine nurse performance and interpretation of HAND using a simplified approach for RHD screening. Two nurses received training on HAND and a simplified screening approach. Consented students at two schools in Uganda were eligible for participation. A simplified approach (HAND performed and interpreted by a non-expert) was compared with the reference standard (standard portable echocardiography, performed and interpreted by experts according to the 2012 World Heart Federation guidelines). Reasons for false-positive and false-negative HAND studies were identified. A total of 1002 children were consented, with 956 (11.1 years, 41.8% male) having complete data for review. Diagnoses included: 913 (95.5%) children were classified normal, 32 (3.3%) borderline RHD and 11 (1.2%) definite RHD. The simplified approach had a sensitivity of 74.4% (58.8% to 86.5%) and a specificity of 78.8% (76.0% to 81.4%) for any RHD (borderline and definite). Sensitivity improved to 90.9% (58.7% to 98.5%) for definite RHD. Identification and measurement of erroneous colour jets was the most common reason for false-positive studies (n=164/194), while missed mitral regurgitation and shorter regurgitant jet lengths with HAND were the most common reasons for false-negative studies (n=10/11). Non-expert-led HAND screening programmes offer a potential solution to financial and workforce barriers that limit widespread RHD screening. Nurses trained on HAND using a simplified approach had reasonable sensitivity and specificity for RHD screening. Information on reasons for false-negative and false-positive screening studies should be used to inform future training protocols, which could lead to improved screening performance. 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/
Pitfalls of diagnosing urinary tract infection in infants and young children.
Yamasaki, Yasuhito; Uemura, Osamu; Nagai, Takuhito; Yamakawa, Satoshi; Hibi, Yoshiko; Yamamoto, Masaki; Nakano, Masaru; Kasahara, Katsuaki; Bo, Zhang
2017-07-01
The aim of this study was to examine the sensitivity and specificity of pyuria-based diagnosis of urinary tract infection (UTI) in urine collected by transurethral catheterization, and the reliability of diagnosis of pyuria in urine collected in a perineal bag. The gold standard for UTI diagnosis is significant colony counts of a single organism in urine obtained in a sterile manner. We enrolled 301 patients who underwent medical examination at the present hospital for possible UTI between January 2005 and December 2009. We collected 438 urine samples by transurethral catheterization. We investigated the accuracy of pyuria-based diagnosis of UTI using transurethral catheterization urine specimens, and the reliability of diagnosis of pyuria using bag-collected urine specimens. The false-negative rate of UTI diagnosis based on pyuria in transurethral catheterization urine sediments was 9.0%; there was no significant difference in the false-negative rate of UTI diagnosis between boys and girls. Approximately 28% of pyuria-positive bag-collected urine specimens were pyuria negative on transurethral catheterization; this rate was significantly higher in girls than in boys (56.7% vs. 8.9%, P < 0.0001). The absence of pyuria in transurethral catheterization urine sediments does not rule out UTI. Pyuria in bag-collected urine specimens frequently consists of urine leukocytes from external genitalia as well as from the urinary tract. © 2017 Japan Pediatric Society.
Added Value of Contrast-Enhanced Spectral Mammography in Postscreening Assessment.
Tardivel, Anne-Marie; Balleyguier, Corinne; Dunant, Ariane; Delaloge, Suzette; Mazouni, Chafika; Mathieu, Marie-Christine; Dromain, Clarisse
2016-09-01
To assess the value on diagnostic and treatment management of contrast-enhanced spectral mammography (CESM), as adjunct to mammography (MG) and ultrasound (US) in postscreening in a breast cancer unit for patients with newly diagnosed breast cancer or with suspicious findings on conventional imaging. Retrospective review of routine use of bilateral CESM performed between September 2012 and September 2013 in 195 women with suspicious or undetermined findings on MG and/or US. CESM images were blindly reviewed by two radiologists for BI-RADS(®) assessment and probability of malignancy. Each lesion was definitely confirmed either with histopathology or follow-up. Two hundred and ninety-nine lesions were detected (221 malignant). CESM sensitivity, specificity, positive-predictive value and negative-predictive value were 94% (CI: 89-96%), 74% (CI: 63-83%), 91% (CI: 86-94%) and 81% (CI: 70-89%), respectively, with 18 false positive and 14 false negative. CESM changed diagnostic and treatment strategy in 41 (21%) patients either after detection of additional malignant lesions in 38 patients (19%)-with a more extensive surgery (n = 21) or neo-adjuvant chemotherapy (n = 1)-or avoiding further biopsy for 20 patients with negative CESM. CESM can be performed easily in a clinical assessment after positive breast cancer screening and may change significantly the diagnostic and treatment strategy through breast cancer staging. © 2016 Wiley Periodicals, Inc.
Tam, Yuk Him; Wong, Yuen Shan; Chan, Kin Wai; Pang, Kristine Kit Yi; Tsui, Siu Yan; Mou, Jennifer Wai Cheung; Sihoe, Jennifer Dart Yin; Lee, Kim Hung
2013-04-01
Transumbilical or transinguinal laparoscopic evaluation for contralateral patent processus vaginalis (CPPV) is commonly performed during laparoscopic or open hernia repair in children but may occasionally give false-negative findings. A retrospective study was conducted to compare 2 cohorts of children who underwent laparoscopic repair for clinically demonstrated unilateral inguinal hernia and evaluation for CPPV by transumbilical laparoscopy during the study periods of 2004 to 2007 (cohort 1) and 2008 to 2011 (cohort 2). Cohort 1 was a known historical cohort with CPPV being evaluated by laparoscopic inspection alone, whereas additional maneuvers were adopted in cohort 2. There were 395 and 564 patients in cohorts 1 and 2, respectively. There was no difference between the 2 cohorts in age of patients, sex distribution, laterality of clinically demonstrated inguinal hernia, and follow-up period at the time of data collection. More CPPV were diagnosed in cohort 2 than cohort 1(36.2% vs 25.8%; P < .01). 4 children (1.4%) developed metachronous inguinal hernia following negative laparoscopic evaluation for CPPV in cohort 1 compared with none from cohort 2 at a similar median follow-up period (P < .05). The additional maneuvers appear to be superior to laparoscopic inspection alone to evaluate CPPV during laparoscopic hernia repair in children. Copyright © 2013 Elsevier Inc. All rights reserved.
Thavarajah, M; Szamocki, S; Komath, D; Cascarini, L; Heliotis, M
2015-01-01
300 cases of non-melanoma cutaneous lesion procedures carried out by the Oral and Maxillofacial Surgery and Dermatology departments in a North West London hospital over a 6 month period between September 2011 and February 2012 were included in a retrospective case control study. The results from each speciality were compared. The mean age of the OMFS group was 75.8 years compared to 69.9 years in the dermatology group. There was no statistically significant difference in gender between the 2 groups. The OMFS group treated a higher proportion of atypical (17%) and malignant (64.9%) cases compared to the dermatology group (11.3% and 50.5% respectively). This could also account for the fact that the OMFS group carried out a higher number of full excisions compared to dermatology. Both groups had a similar number of false positives (a benign lesion initially diagnosed as malignant) and a similar proportion of false negatives (a malignant lesion initially diagnosed as benign). Overall, the results show that both specialities had similar outcomes when managing non-melanoma cutaneous lesions. Both groups adhere to the guidelines set out by the British Association of Dermatologists and the National Institute of Clinical Excellence when managing such lesions. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.
Speich, Benjamin; Ali, Said M; Ame, Shaali M; Albonico, Marco; Utzinger, Jürg; Keiser, Jennifer
2015-02-05
An accurate diagnosis of soil-transmitted helminthiasis is important for individual patient management, for drug efficacy evaluation and for monitoring control programmes. The Kato-Katz technique is the most widely used method detecting soil-transmitted helminth eggs in faecal samples. However, detailed analyses of quality control, including false-positive and faecal egg count (FEC) estimates, have received little attention. Over a 3-year period, within the frame of a series of randomised controlled trials conducted in Pemba, United Republic of Tanzania, 10% of randomly selected Kato-Katz thick smears were re-read for Trichuris trichiura and Ascaris lumbricoides eggs. In case of discordant result (i.e. positive versus negative) the slides were re-examined a third time. A result was assumed to be false-positive or false-negative if the result from the initial reading did not agree with the quality control as well as the third reading. We also evaluated the general agreement in FECs between the first and second reading, according to internal and World Health Organization (WHO) guidelines. From the 1,445 Kato-Katz thick smears subjected to quality control, 1,181 (81.7%) were positive for T. trichiura and 290 (20.1%) were positive for A. lumbricoides. During quality control, very low rates of false-positive results were observed; 0.35% (n = 5) for T. trichiura and 0.28% (n = 4) for A. lumbricoides. False-negative readings of Kato-Katz thick smears were obtained in 28 (1.94%) and 6 (0.42%) instances for T. trichiura and A. lumbricoides, respectively. A high frequency of discordant results in FECs was observed (i.e. 10.0-23.9% for T. trichiura, and 9.0-11.4% for A. lumbricoides). Our analyses show that the rate of false-positive diagnoses of soil-transmitted helminths is low. As the probability of false-positive results increases after examination of multiple stool samples from a single individual, the potential influence of false-positive results on epidemiological studies and anthelminthic drug efficacy studies should be determined. Existing WHO guidelines for quality control might be overambitious and might have to be revised, specifically with regard to handling disagreements in FECs.
Alloy, Lauren B; Black, Shimrit K; Young, Mathew E; Goldstein, Kim E; Shapero, Benjamin G; Stange, Jonathan P; Boccia, Angelo S; Matt, Lindsey M; Boland, Elaine M; Moore, Lauren C; Abramson, Lyn Y
2012-01-01
We examined the concurrent associations between multiple cognitive vulnerabilities to depression featured in hopelessness theory, Beck's theory, and response styles theory and depressive symptoms and diagnoses in a sample of early adolescents. We also examined the specificity of these cognitive vulnerabilities to depression versus anxiety and externalizing psychopathology, controlling for co-occurring symptoms and diagnoses. Male and female, Caucasian and African American, 12- to 13-year-old adolescents were assessed in a cross-sectional design. Cognitive vulnerabilities of hopelessness, inferential style, rumination, and self-referent information processing were assessed with self-reports and behavioral tasks. Symptoms and diagnoses of depressive, anxiety, and externalizing disorders were assessed with self-report questionnaires and diagnostic interviews. Hopelessness exhibited the greatest specificity to depressive symptoms and diagnoses, whereas negative inferential styles, rumination, and negative self-referent information processing were associated with both depressive and anxiety symptoms and diagnoses and, in some cases, with externalizing disorders. Consistent with cognitive theories of depression, hopelessness, negative inferential styles, rumination, and negative self-referent information processing were associated with depressive symptoms and diagnoses. However, with the exception of hopelessness, most of the remaining cognitive vulnerabilities were not specific to depression. With further maturation of our sample, these cognitive vulnerabilities may become more specific to depression as cognitive styles further develop and consolidate, the rates of depression increase, and individuals' presentations of psychopathology become more differentiated.
Alloy, Lauren B.; Black, Shimrit K.; Young, Mathew E.; Goldstein, Kim E.; Shapero, Benjamin G.; Stange, Jonathan P.; Boccia, Angelo S.; Matt, Lindsey M.; Boland, Elaine M.; Moore, Lauren C.; Abramson, Lyn Y.
2012-01-01
Objective We examined the concurrent associations between multiple cognitive vulnerabilities to depression featured in Hopelessness Theory, Beck’s Theory, and Response Styles Theory and depressive symptoms and diagnoses in a sample of early adolescents. We also examined the specificity of these cognitive vulnerabilities to depression versus anxiety and externalizing psychopathology, controlling for co-occurring symptoms and diagnoses. Method Male and female, Caucasian and African-American, 12–13 year old adolescents were assessed in a cross-sectional design. Cognitive vulnerabilities of hopelessness, inferential style, rumination, and self-referent information processing were assessed with self-reports and behavioral tasks. Symptoms and diagnoses of depressive, anxiety, and externalizing disorders were assessed with self-report questionnaires and diagnostic interviews. Results Hopelessness exhibited the greatest specificity to depressive symptoms and diagnoses, whereas negative inferential styles, rumination, and negative self-referent information processing were associated with both depressive and anxiety symptoms and diagnoses and, in some cases, with externalizing disorders. Conclusions Consistent with cognitive theories of depression, hopelessness, negative inferential styles, rumination, and negative self-referent information processing were associated with depressive symptoms and diagnoses. However, with the exception of hopelessness, most of the remaining cognitive vulnerabilities were not specific to depression. With further maturation of our sample, these cognitive vulnerabilities may become more specific to depression as cognitive styles further develop and consolidate, the rates of depression increase, and individuals’ presentations of psychopathology become more differentiated. PMID:22853629
Cistaro, Angelina; Cassalia, Laura; Ferrara, Cinzia; Quartuccio, Natale; Evangelista, Laura; Bianchi, Maurizio; Fagioli, Franca; Bisi, Gianni; Baldari, Sergio; Zanella, Alessandro; Pillon, Marta; Zucchetta, Pietro; Burei, Marta; Sala, Alessandra; Guerra, Luca; Guglielmo, Priscilla; Burnelli, Roberta; Panareo, Stefano; Scalorbi, Federica; Rambaldi, Ilaria; Piccardo, Arnoldo; Garaventa, Alberto; Familiari, Demetrio; Fornito, Maria Concetta; Lopci, Egesta; Mascarin, Maurizio; Altini, Corinna; Ferrari, Cristina; Perillo, Teresa; Santoro, Nicola; Borsatti, Eugenio; Rubini, Giuseppe
2018-06-01
The present study investigated the utility of fluorine-18 ( 18 F) fluoro-2-deoxy-d-glucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) in assessing bone marrow involvement (BMI) compared with bone marrow biopsy (BMB) in newly diagnosed pediatric Hodgkin lymphoma (HL). A total of 224 pediatric patients with HL underwent 18 F-FDG PET/CT at staging. BMB or follow-up imaging was used as the standard of reference for the evaluation of BMI. 18 F-FDG PET/CT was negative for BMI in 193 cases. Of the 193 patients, the findings for 16 were originally reported as doubtful and later interpreted as negative for BMI, with negative findings on follow-up imaging and BMB. At BMB, 1 of the 16 patients (6.25%) had BMI. Of the 193 patients, 192 (99.48%) had negative BMB findings. Thus, the 18 F-FDG PET/CT findings were truly negative for 192 patients and falsely negative for 1 patient for BMI. 18 F-FDG PET/CT showed high diagnostic performance in the evaluation of BMI in pediatric HL. Thus, BMB should be ideally reserved for patients presenting with doubtful 18 F-FDG PET/CT findings for BMI. Copyright © 2018 Elsevier Inc. All rights reserved.
Numata, Takanori; Araya, Jun; Yoshii, Yutaka; Shimizu, Kenichiro; Hara, Hiromichi; Nakayama, Katsutoshi; Kuwano, Kazuyoshi
2015-11-01
It is difficult to verify the bacteriological diagnosis of Mycobacterium avium complex (MAC) infection. The anti-glycopeptidolipid (GPL)-core IgA antibody test was recently developed as a diagnostic method for MAC pulmonary disease. Only a few studies evaluate its clinical efficacy. We conducted retrospective evaluations of clinical characteristics of patients suspected of MAC infection to explore the usefulness of the anti-GPL-core IgA antibody test. We retrospectively evaluated 296 patients who were suspected to have MAC infection and underwent anti-GPL-core IgA antibody test between March 2013 and July 2014 in Jikei University hospital. A total of 29 patients were diagnosed with 'definite MAC' based on the American Thoracic Society (ATS) criteria with multiple identifications of MAC. On the other hand, 106 patients were diagnosed with other pulmonary diseases than MAC. The sensitivity and specificity of anti-GPL-core IgA antibody test for MAC diagnosis were 58.6% and 98.1%, respectively. The definite MAC group showed no significant differences in strains, treatment history or number of segments involved. The duration of MAC disease in the positive-antibody group was significantly longer than in the negative-antibody group (P = 0.046). A significant increase in the false-negative rate was observed in patients with malignant disease (P = 0.029). The anti-GPL-core IgA antibody test demonstrated high sensitivity and specificity for the diagnosis of MAC infection especially in patients without malignant diseases. © 2015 Asian Pacific Society of Respirology.
Duterme, Sophie; Vanhoof, Raymond; Vanderpas, Jean; Pierard, Denis; Huygen, Kris
2016-04-01
Report on the pitfalls of serodiagnosis of pertussis in Belgium for 2013 by the NRC Bordetella. Determine cases of acute infection using an anti-pertussis toxin (PT) IgG antibody ELISA. A total of 2471 serum samples were received. Clinical information on the duration of cough (at moment of blood sampling) is essential for a reliable interpretation of the results. In order to avoid false negative results, 213 samples for which this information was lacking were not tested. For a total of 2179 patients tested, 520 (23.9%) had antibody levels indicative of an acute infection, 261 (12%) samples were diagnosed as positive (indicative of a pertussis infection or vaccination during the last year), 143 (6.7%) samples were classified as doubtful and 752 (34,5%) (35.5%) were diagnosed as negative. The serodiagnosis of pertussis has limited value for the early diagnosis of the disease and PCR analysis on nasopharyngeal swabs is the method of choice during the first 2 weeks and always for young children <1 year old. For sera collected during the first 2 weeks with anti-PT levels below the threshold for acute infection, a second sample collected 2-3 weeks later is needed a definitive diagnosis. For 503 (23.0%) early samples, a second serum sample was requested but not provided. For 85 patients, for whom a second sample was received, 12.9% were eventually diagnosed as having an acute infection. In order to generate reliable serodiagnostic results for pertussis, serum samples should preferentially be collected 3 weeks after onset of symptoms.
2014-01-01
Introduction Interval cancers are tumors arising after a negative screening episode and before the next screening invitation. They can be classified into true interval cancers, false-negatives, minimal-sign cancers, and occult tumors based on mammographic findings in screening and diagnostic mammograms. This study aimed to describe tumor-related characteristics and the association of breast density and tumor phenotype within four interval cancer categories. Methods We included 2,245 invasive tumors (1,297 screening-detected and 948 interval cancers) diagnosed from 2000 to 2009 among 645,764 women aged 45 to 69 who underwent biennial screening in Spain. Interval cancers were classified by a semi-informed retrospective review into true interval cancers (n = 455), false-negatives (n = 224), minimal-sign (n = 166), and occult tumors (n = 103). Breast density was evaluated using Boyd’s scale and was conflated into: <25%; 25 to 50%; 50 to 75%; >75%. Tumor-related information was obtained from cancer registries and clinical records. Tumor phenotype was defined as follows: luminal A: ER+/HER2- or PR+/HER2-; luminal B: ER+/HER2+ or PR+/HER2+; HER2: ER-/PR-/HER2+; triple-negative: ER-/PR-/HER2-. The association of tumor phenotype and breast density was assessed using a multinomial logistic regression model. Adjusted odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. All statistical tests were two-sided. Results Forty-eight percent of interval cancers were true interval cancers and 23.6% false-negatives. True interval cancers were associated with HER2 and triple-negative phenotypes (OR = 1.91 (95% CI:1.22-2.96), OR = 2.07 (95% CI:1.42-3.01), respectively) and extremely dense breasts (>75%) (OR = 1.67 (95% CI:1.08-2.56)). However, among true interval cancers a higher proportion of triple-negative tumors was observed in predominantly fatty breasts (<25%) than in denser breasts (28.7%, 21.4%, 11.3% and 14.3%, respectively; <0.001). False-negatives and occult tumors had similar phenotypic characteristics to screening-detected cancers, extreme breast density being strongly associated with occult tumors (OR = 6.23 (95% CI:2.65-14.66)). Minimal-sign cancers were biologically close to true interval cancers but showed no association with breast density. Conclusions Our findings revealed that both the distribution of tumor phenotype and breast density play specific and independent roles in each category of interval cancer. Further research is needed to understand the biological basis of the overrepresentation of triple-negative phenotype among predominantly fatty breasts in true interval cancers. PMID:24410848
Comparison of the accuracy rates of 3-T and 1.5-T MRI of the knee in the diagnosis of meniscal tear.
Grossman, Jeffrey W; De Smet, Arthur A; Shinki, Kazuhiko
2009-08-01
The purpose of this study was to compare the accuracy of 3-T MRI with that of 1.5-T MRI of the knee in the diagnosis of meniscal tear and to analyze the causes of diagnostic error. We reviewed the medical records and original MRI interpretations of 100 consecutive patients who underwent 3-T MRI of the knee and of 100 consecutive patients who underwent 1.5-T MRI of the knee to determine the accuracy of diagnoses of meniscal tear. Knee arthroscopy was the reference standard. We retrospectively reviewed all MRI diagnostic errors to determine the cause of the errors. At arthroscopy, 109 medial and 77 lateral meniscal tears were identified in the 200 patients. With two abnormal MR images indicating a meniscal tear, the sensitivity and specificity for medial tear were 92.7% and 82.2% at 1.5-T MRI and 92.6% and 76.1% at 3-T MRI (p = 1.0, p = 0.61). The sensitivity and specificity for lateral tears were 68.4% and 95.2% at 1.5-T MRI and 69.2% and 91.8% at 3-T MRI (p = 1.0, p = 0.49). Of the false-positive diagnoses of medial meniscal tear, five of eight at 1.5 T and seven of 11 at 3 T were apparent peripheral longitudinal tears of the posterior horn. Fifteen of the 26 missed medial and lateral meniscal tears were not seen in retrospect even with knowledge of the tear type and location. Allowing for sample size limitations, we found comparable accuracy of 3-T and 1.5-T MRI of the knee in the diagnosis of meniscal tear. The causes of false-positive and false-negative MRI diagnoses of meniscal tear are similar for 3-T and 1.5-T MRI.
Establishing the Cause of Anemia in a Premature Newborn Infant.
den Besten, Gijs; van der Weide, Karen; Schuerman, Frank A B A; Michael Cotten, C; Rondeel, Jan M M
2018-06-02
The three major causes of anemia in neonates are blood loss, decreased red blood cell production, and increased degradation of erythrocytes. Establishing the cause of anemia in a neonate born prematurely can be challenging. Clinically, fetomaternal hemorrhage (FMH) can be difficult to diagnose-the condition often presents only after the manifestation of severe fetal anemia. FMH can be confirmed by determining the fetal hemoglobin F fraction in the mother, which is traditionally performed using the Kleihauer-Betke test (KBT). Herein, we present a case study of a newborn baby boy of Dutch ethnicity with massive FMH and negative KBT result. The KBT result appeared to be false-negative due to AO antagonism. However, the results of an additional marker alpha-fetoprotein (AFP) test confirmed the diagnosis of massive FMH. Therefore, measuring AFP in maternal blood can be helpful in confirming FMH in unexplained anemia of the neonate.
Porter, Stephen; Taylor, Kristian; Ten Brinke, Leanne
2008-01-01
Despite a large body of false memory research, little has addressed the potential influence of an event's emotional content on susceptibility to false recollections. The Paradoxical Negative Emotion (PNE) hypothesis predicts that negative emotion generally facilitates memory but also heightens susceptibility to false memories. Participants were asked whether they could recall 20 "widely publicised" public events (half fictitious) ranging in emotional valence, with or without visual cues. Participants recalled a greater number of true negative events (M=3.31/5) than true positive (M=2.61/5) events. Nearly everyone (95%) came to recall at least one false event (M=2.15 false events recalled). Further, more than twice as many participants recalled any false negative (90%) compared to false positive (41.7%) events. Negative events, in general, were associated with more detailed memories and false negative event memories were more detailed than false positive event memories. Higher dissociation scores were associated with false recollections of negative events, specifically.
Contrast Extravasation versus Hemorrhage after Thrombectomy in Patients with Acute Stroke.
Yedavalli, Vivek; Sammet, Steffen
2017-11-01
Intra-arterial recanalization postprocedural imaging in stroke patients can result in diagnostic complications due to hyperdensities on noncontrast computed tomography (CT), which may represent either contrast extravasation or intracranial hemorrhage. If these lesions are hemorrhage, then they are risk factors becoming symptomatic, which, if not distinguished, can alter clinical management. We investigate the effects of iodinated contrast on postprocedural magnetic resonance imaging (MRI) and prevalence of equivocal imaging interpretations of postprocedural extravasated contrast versus hemorrhage while identifying protocol pitfalls. We identified 10 patients diagnosed with ischemic stroke who underwent intra-arterial recanalization in a 5-year period. These patients demonstrated a hyperdensity on a postprocedural CT within 24 hours, underwent an MRI within 48 hours, and an additional confirmatory noncontrast CT at least 72 hours postprocedure. Postprocedural MRI in all 10 stroke patients demonstrated T 1 - and T 2 -relaxation time changes due to residual iodine contrast agents. This lead to false positive postprocedural hemorrhage MRI interpretations in 2/10 patients, 3/10 false negative interpretations of contrast extravasation, and 5/10 equivocal interpretations suggesting extravasation or hemorrhage. Of these five cases, two were performed with gadolinium. MRI done within 48 hours postprocedure can lead to false positive hemorrhage or false negative contrast extravasation interpretations in stroke patients possibly due to effects from the administered angiographic contrast. Additionally, MRI should be done both after 72 hours for confirmation and without gadolinium contrast as the effects of the gadolinium contrast and residual angiographic contrast could lead to misdiagnosis. Copyright © 2017 by the American Society of Neuroimaging.
Borgstein, P J; Gordijn, R V; Eijsbouts, Q A; Cuesta, M A
1997-09-01
The aggressive surgical approach to patients suspected of having acute appendicitis for fear of perforation, and the inaccuracy of available diagnostic methods lead to an unacceptably high negative appendicectomy rate, especially in young women, in whom gynecological disorders frequently mimic appendicitis. Our objectives were to determine the value of diagnostic laparoscopy in women of child-bearing age to reduce the number of negative laparotomies and establish the correct diagnosis to allow prompt and appropriate treatment. 161 consecutive adult female patients under 50 years of age with a clinical diagnosis of acute appendicitis underwent diagnostic laparoscopy prior to the planned appendicectomy. If an inflamed appendix was found, appendicectomy was usually done through a muscle-splitting McBurney incision. Other diagnoses were treated accordingly. A normal appendix was not removed. Results were compared to a group of 42 similar patients in whom the laparoscopy was omitted for various reasons, to 23 postmenopausal women, and to all 137 male adults, directly operated by the McBurney approach. After laparoscopy, 55% of the patients required appendicectomy for appendicitis while in 23% a gynecological diagnosis was made in spite of previous examination by a gynecologist. Fourteen percent had a negative laparoscopy. There were no false-negative results. The negative appendicectomy rate after laparoscopy was 5% due to two false positives and eight laparoscopy failures. In the group of fertile females who escaped laparoscopy the negative appendicectomy rate was 38%. The respective rates for postmenopausal women and men were 4% and 8%. All women of child-bearing age suspected of having acute appendicitis should undergo diagnostic laparoscopy prior to the planned appendicectomy, regardless of the certainty of the preoperative diagnosis. This is currently the only way to reduce the negative appendicectomy rate and establish a correct diagnosis allowing prompt and appropriate treatment. In male patients and postmenopausal women one may proceed directly to emergency appendicectomy.
Should bedside sonography be used first to diagnose pneumothorax secondary to blunt trauma?
Donmez, Halil; Tokmak, Turgut Tursem; Yildirim, Afra; Buyukoglan, Hakan; Ozturk, Mehmet; Yaşar Ayaz, Umit; Mavili, Ertugrul
2012-01-01
BACKGROUND.: Our purpose was to evaluate the effectiveness of bedside sonography (US) in the detection of pneumothorax secondary to blunt thoracic trauma. METHODS.: In this prospective study, 240 hemithoraces of 120 consecutive patients with multiple trauma were evaluated with chest radiographs (CXR) and bedside thoracic US for the diagnosis of pneumothorax. CT examinations were performed in 68 patients. Fifty-two patients who did not undergo CT examinations were excluded from the study. US examinations were performed independently at bedside by two radiologists who were not informed about CXR and CT findings. CXRs were interpreted by two radiologists who were unaware of the US and CT results. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CXR and US were calculated. RESULTS.: One hundred thirty-six hemithoraces were assessed in 68 patients. A total of 35 pneumothoraces were detected in 33 patients. On US, the diagnosis of pneumothorax was correct in 32 hemithoraces. In 98 hemithoraces without pneumothorax, US was normal. With US examination, there were three false-positive and three false-negative results. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of US were 91.4%, 97%, 91.4%, 97%, and 97%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CXR were 82.7%, 89.7%, 68.5%, 95%, and 89.5%, respectively. CONCLUSIONS.: Bedside thoracic US is an accurate method that can be used in trauma patients instead of CXR for the detection of pneumothorax. Copyright © 2012 Wiley Periodicals, Inc.
Establishing a sample-to cut-off ratio for lab-diagnosis of hepatitis C virus in Indian context.
Tiwari, Aseem K; Pandey, Prashant K; Negi, Avinash; Bagga, Ruchika; Shanker, Ajay; Baveja, Usha; Vimarsh, Raina; Bhargava, Richa; Dara, Ravi C; Rawat, Ganesh
2015-01-01
Lab-diagnosis of hepatitis C virus (HCV) is based on detecting specific antibodies by enzyme immuno-assay (EIA) or chemiluminescence immuno-assay (CIA). Center for Disease Control reported that signal-to-cut-off (s/co) ratios in anti-HCV antibody tests like EIA/CIA can be used to predict the probable result of supplemental test; above a certain s/co value it is most likely to be true-HCV positive result and below that certain s/co it is most likely to be false-positive result. A prospective study was undertaken in patients in tertiary care setting for establishing this "certain" s/co value. The study was carried out in consecutive patients requiring HCV testing for screening/diagnosis and medical management. These samples were tested for anti-HCV on CIA (VITROS(®) Anti-HCV assay, Ortho-Clinical Diagnostics, New Jersey) for calculating s/co value. The supplemental nucleic acid test used was polymerase chain reaction (PCR) (Abbott). PCR test results were used to define true negatives, false negatives, true positives, and false positives. Performance of different putative s/co ratios versus PCR was measured using sensitivity, specificity, positive predictive value and negative predictive value and most appropriate s/co was considered on basis of highest specificity at sensitivity of at least 95%. An s/co ratio of ≥6 worked out to be over 95% sensitive and almost 92% specific in 438 consecutive patient samples tested. The s/co ratio of six can be used for lab-diagnosis of HCV infection; those with s/co higher than six can be diagnosed to have HCV infection without any need for supplemental assays.
Small strokes causing severe vertigo: frequency of false-negative MRIs and nonlacunar mechanisms.
Saber Tehrani, Ali S; Kattah, Jorge C; Mantokoudis, Georgios; Pula, John H; Nair, Deepak; Blitz, Ari; Ying, Sarah; Hanley, Daniel F; Zee, David S; Newman-Toker, David E
2014-07-08
Describe characteristics of small strokes causing acute vestibular syndrome (AVS). Ambispective cross-sectional study of patients with AVS (acute vertigo or dizziness, nystagmus, nausea/vomiting, head-motion intolerance, unsteady gait) with at least one stroke risk factor from 1999 to 2011 at a single stroke referral center. Patients underwent nonquantitative HINTS "plus" examination (head impulse, nystagmus, test-of-skew plus hearing), neuroimaging to confirm diagnoses (97% by MRI), and repeat MRI in those with initially normal imaging but clinical signs of a central lesion. We identified patients with diffusion-weighted imaging (DWI) strokes ≤10 mm in axial diameter. Of 190 high-risk AVS presentations (105 strokes), we found small strokes in 15 patients (median age 64 years, range 41-85). The most common vestibular structure infarcted was the inferior cerebellar peduncle (73%); the most common stroke location was the lateral medulla (60%). Focal neurologic signs were present in only 27%. The HINTS "plus" battery identified small strokes with greater sensitivity than early MRI-DWI (100% vs 47%, p < 0.001). False-negative initial MRIs (6-48 hours) were more common with small strokes than large strokes (53% [n = 8/15] vs 7.8% [n = 7/90], p < 0.001). Nonlacunar stroke mechanisms were responsible in 47%, including 6 vertebral artery occlusions or dissections. Small strokes affecting central vestibular projections can present with isolated AVS. The HINTS "plus" hearing battery identifies these patients with greater accuracy than early MRI-DWI, which is falsely negative in half, up to 48 hours after onset. We found nonlacunar mechanisms in half, suggesting greater risk than might otherwise be assumed for patients with such small infarctions. © 2014 American Academy of Neurology.
Wei, Wei-Qi; Leibson, Cynthia L; Ransom, Jeanine E; Kho, Abel N; Caraballo, Pedro J; Chai, High Seng; Yawn, Barbara P; Pacheco, Jennifer A
2012-01-01
Objective To evaluate data fragmentation across healthcare centers with regard to the accuracy of a high-throughput clinical phenotyping (HTCP) algorithm developed to differentiate (1) patients with type 2 diabetes mellitus (T2DM) and (2) patients with no diabetes. Materials and methods This population-based study identified all Olmsted County, Minnesota residents in 2007. We used provider-linked electronic medical record data from the two healthcare centers that provide >95% of all care to County residents (ie, Olmsted Medical Center and Mayo Clinic in Rochester, Minnesota, USA). Subjects were limited to residents with one or more encounter January 1, 2006 through December 31, 2007 at both healthcare centers. DM-relevant data on diagnoses, laboratory results, and medication from both centers were obtained during this period. The algorithm was first executed using data from both centers (ie, the gold standard) and then from Mayo Clinic alone. Positive predictive values and false-negative rates were calculated, and the McNemar test was used to compare categorization when data from the Mayo Clinic alone were used with the gold standard. Age and sex were compared between true-positive and false-negative subjects with T2DM. Statistical significance was accepted as p<0.05. Results With data from both medical centers, 765 subjects with T2DM (4256 non-DM subjects) were identified. When single-center data were used, 252 T2DM subjects (1573 non-DM subjects) were missed; an additional false-positive 27 T2DM subjects (215 non-DM subjects) were identified. The positive predictive values and false-negative rates were 95.0% (513/540) and 32.9% (252/765), respectively, for T2DM subjects and 92.6% (2683/2898) and 37.0% (1573/4256), respectively, for non-DM subjects. Age and sex distribution differed between true-positive (mean age 62.1; 45% female) and false-negative (mean age 65.0; 56.0% female) T2DM subjects. Conclusion The findings show that application of an HTCP algorithm using data from a single medical center contributes to misclassification. These findings should be considered carefully by researchers when developing and executing HTCP algorithms. PMID:22249968
van der Geest, Ivana M; van den Heuvel-Eibrink, Marry M; Passchier, Jan; van den Hoed-Heerschop, Corry; Pieters, Rob; Darlington, Anne-Sophie E
2014-07-01
The aim was to investigate the influence of parents' negative mood state and parenting stress on behavior in children with newly diagnosed cancer. A total of 123 parents (n=58 fathers, n=65 mothers) of 67 children with newly diagnosed cancer completed three questionnaires separately at the same time measuring parents' negative mood state, parenting stress, and child behavior problems. Parents' negative mood state was weakly correlated to more child behavior problems (r=0.31, p<0.01), and higher levels of parenting stress were strongly correlated to more child behavior problems (r=0.61, p<0.01). Mediation analyses indicated that the relationship between parents' negative mood state and child behavior problems (c=0.29, p=0.02 (fathers); c=0.25, p=0.04 (mothers)) became non-significant after mediating for parenting stress (c'=0.003, p=0.98 (fathers); c'=0.10, p=0.42 (mothers)). The indirect effect of parents' negative mood state and child behavior problems was only significant for fathers (95% CI [0.12; 0.51]), indicating that parenting stress mediates the effect between fathers' negative mood state and child behavior problems. This is the first study to demonstrate the mediational role of parenting stress in fathers of a child with newly diagnosed cancer. Copyright © 2014 John Wiley & Sons, Ltd.
Evaluation of brush cytology and DNA image cytometry for the detection of cancer of the oral cavity.
Kaur, Manveen; Handa, Uma; Mohan, Harsh; Dass, Arjun
2016-03-01
Cancer of the oral cavity is the sixth most common malignancy reported worldwide. This study was undertaken to evaluate the efficacy of brush cytology and the adjunctive role of DNA image cytometry (ICM) in the diagnosis of oral cancer. Oral brush smears and biopsy were obtained from 100 consecutive patients presenting with suspicious oral lesions. DNA-ICM was performed on 96 cytology smears which had adequate cellularity. On cytology, 54 cases were benign, 36 were malignant, 6 were suspicious for malignancy, and 4 were inadequate due to scanty cellularity. On histopathologic examination, 49 cases were diagnosed as squamous cell carcinoma and 51 cases as benign. The sensitivity of brush cytology for the detection of cancer was 83.3% and the specificity was 95.8%. The positive and negative predictive values were 95.2% and 85.2%, respectively, with a diagnostic accuracy of 86%. Out of 96 cases analyzed by image analysis to assess DNA ploidy, 33 cases were aneuploid and 63 were diploid. The sensitivity, specificity, positive predictive value, and negative predictive value of DNA-ICM were 68.7%, 100%, 100%, and 76.1%, respectively, giving a diagnostic accuracy of 81%. The combination of cytology and DNA cytometry increased the sensitivity to 92% and specificity to 100%. The study demonstrates the usefulness of DNA-ICM as an adjunct to brush cytology to diagnose oral cancer. It reduces the false negative cases on cytology and also adds to objectivity in cytologically doubtful cases. © 2016 Wiley Periodicals, Inc.
Multiplex polymerase chain reaction test for the diagnosis of acute viral hepatitis A.
Heo, Nae-Yun; Lim, Young-Suk; An, Jihyun; Ko, Sun-Young; Oh, Heung-Bum
2012-12-01
The early diagnosis of acute hepatitis A (AHA) is hindered because serum IgM against hepatitis A virus (HAV) can yield false-negative results during the window period. This study evaluated the diagnostic accuracy of a polymerase chain reaction (PCR) kit for HAV RNA for the diagnosis of AHA. Samples were collected from 136 patients with acute severe hepatitis at their admission to Asan Medical Center between June 2010 and July 2010. Samples were analyzed for serum IgM anti-HAV using an immunoassay test and for qualitative HAV RNA using the Magicplex HepaTrio PCR test kit. The diagnostic accuracies of these methods were tested on the basis of clinical and laboratory diagnoses of AHA. The concordance rate and kappa value between IgM anti-HAV and HAV RNA PCR were 88.2% and 0.707, respectively. For the diagnosis of AHA, the sensitivity and specificity of IgM anti-HAV were 90.7% and 100%, respectively, when an "equivocal" result was regarded as positive; and 79.1% and 100%, respectively, when an "equivocal" result was regarded as negative. The sensitivity and specificity of HAV RNA PCR were 81.4% and 100%, respectively. All four patients with negative IgM anti-HAV and positive HAV RNA PCR results and all four patients with equivocal IgM anti-HAV RNA and positive HAV RNA PCR results were eventually diagnosed with AHA. The qualitative HAV RNA PCR test has an equivalent diagnostic accuracy for AHA compared to IgM anti-HAV and may be more sensitive during the window period.
Skaane, Per; Kshirsagar, Ashwini; Hofvind, Solveig; Jahr, Gunnar; Castellino, Ronald A
2012-04-01
Double reading improves the cancer detection rate in mammography screening. Single reading with computer-aided detection (CAD) has been considered to be an alternative to double reading. Little is known about the potential benefit of CAD in breast cancer screening with double reading. To compare prospective independent double reading of screen-film (SFM) and full-field digital (FFDM) mammography in population-based screening with retrospective standalone CAD performance on the baseline mammograms of the screen-detected cancers and subsequent cancers diagnosed during the follow-up period. The study had ethics committee approval. A 5-point rating scale for probability of cancer was used for 23,923 (SFM = 16,983; FFDM = 6940) screening mammograms. Of 208 evaluable cancers, 104 were screen-detected and 104 were subsequent (44 interval and 60 next screening round) cancers. Baseline mammograms of subsequent cancers were retrospectively classified in consensus without information about cancer location, histology, or CAD prompting as normal, non-specific minimal signs, significant minimal signs, and false-negatives. The baseline mammograms of the screen-detected cancers and subsequent cancers were evaluated by CAD. Significant minimal signs and false-negatives were considered 'actionable' and potentially diagnosable if correctly prompted by CAD. CAD correctly marked 94% (98/104) of the baseline mammograms of the screen-detected cancers (SFM = 95% [61/64]; FFDM = 93% [37/40]), including 96% (23/24) of those with discordant interpretations. Considering only those baseline examinations of subsequent cancers prospectively interpreted as normal and retrospectively categorized as 'actionable', CAD input at baseline screening had the potential to increase the cancer detection rate from 0.43% to 0.51% (P = 0.13); and to increase cancer detection by 16% ([104 + 17]/104) and decrease interval cancers by 20% (from 44 to 35). CAD may have the potential to increase cancer detection by up to 16%, and to reduce the number of interval cancers by up to 20% in SFM and FFDM screening programs using independent double reading with consensus review. The influence of true- and false-positive CAD marks on decision-making can, however, only be evaluated in a prospective clinical study.
Gerstl, Sibylle; Dunkley, Sophie; Mukhtar, Ahmed; De Smet, Martin; Baker, Samuel; Maikere, Jacob
2010-01-21
Most malaria rapid diagnostic tests (RDTs) use HRP2 detection, including Paracheck-Pf(R), but their utility is limited by persistent false positivity after treatment. PLDH-based tests become negative more quickly, but sensitivity has been reported below the recommended standard of 90%. A new pLDH test, CareStart three-line P.f/PAN-pLDH, claims better sensitivity with continued rapid conversion to negative. The study aims were to 1) compare sensitivity and specificity of CareStart to Paracheck-Pf(R) to diagnose falciparum malaria in children under five years of age, 2) assess how quickly false-positive CareStart tests become negative and 3) evaluate ease of use and inter-reader agreement of both tests. Participants were included if they were aged between two and 59 months, presenting to a Médecins Sans Frontières community health centre in eastern Sierra Leone with suspected malaria defined as fever (axillary temperature > 37.5 degrees C) and/or history of fever in the previous 72 hours and no signs of severe disease. The same capillary blood was used for the RDTs and the blood slide, the latter used as the gold standard reference. All positive participants were treated with supervised artesunate and amodiaquine treatment for three days. Participants with a persistent false-positive CareStart, but a negative blood slide on Day 2, were followed with repeated CareStart and blood slide tests every seven days until CareStart became negative or a maximum of 28 days. Sensitivity of CareStart was 99.4% (CI 96.8-100.0, 168/169) and of Paracheck-Pf(R), 98.8% (95% CI 95.8-99.8, 167/169). Specificity of CareStart was 96.0% (CI 91.9-98.4, 167/174) and of Paracheck-Pf(R), 74.7% (CI 67.6-81.0, 130/174) (p < 0.001). Neither test showed any change in sensitivity with decreasing parasitaemia. Of the 155 eligible follow-up CareStart participants, 63.9% (99/155) had a false-positive test on day 2, 21.3% (33/155) on day 7, 5.8% (9/155) on day 14, 1.9% (3/155) on day 21 and 0.6% (1/155) on day 28. The median time for test negativity was seven days. CareStart was as easy to use and interpret as Paracheck-Pf(R) with excellent inter-reader agreement. Both RDTs were highly sensitive, met WHO standards for the detection of falciparum malaria monoinfections where parasitaemia was >100 parasites/mul and were easy to use. CareStart persistent false positivity decreased quickly after successful anti-malarial treatment, making it a good choice for a RDT for a hyperendemic falciparum malaria area.
Leukocyte Esterase as a Biomarker in the Diagnosis of Periprosthetic Joint Infection.
Wang, Chi; Li, Rui; Wang, Qi; Duan, Jinyan; Wang, Chengbin
2017-01-21
BACKGROUND Total joint arthroplasty (TJA) has been one of the most rewarding interventions for treating patients suffering from joint disorders. However, periprosthetic joint infection (PJI) is a serious complication that frequently accompanies TJA. Our study aimed to investigate the application of the leukocyte esterase (LE) strip in the diagnosis of PJI. MATERIAL AND METHODS From October 2014 to July 2015, 72 patients who had undergone joint puncture after arthroplasty in our hospital were enrolled in this trial. One drop of synovial fluid from each available patient was applied to the LE strip, and the results were observed after 1-3 min. If the color turned to dark purple, we recognized this as a positive result, while other colors were regarded as negative results. Centrifugation was used when the synovial fluid was mixed with blood. The Musculoskeletal Infection Society (MSIS) definition was used as the standard reference to identify whether PJI was found in patients or not. The results of diagnosis and LE strips test were compared, and indicators reflecting diagnostic value were calculated. Correlation of the LE data with erythrocyte sedimentation rate (ESR), elevated C-reactive protein (CRP), synovial white blood cell (WBC) counts, and polymorphonuclear neutrophil (PMN) percentage was calculated. RESULTS By MSIS criteria, 38 patients were diagnosed with PJI and 34 patients were not infected. Two types of LE strip presented the same results with sensitivity of 84.21% (95% confidence interval [CI]: 68.75~93.98%), specificity of 97.06% (95% CI: 84.67~99.93%), positive predictive value (PPV) of 96.97% (95% CI: 84.24~99.92%), and negative predictive value (NPV) of 84.62% (95% CI: 69.47~94.14%). There were one false-positive case and six false-negative cases in this trial. There is a strong correlation between LE strip and synovial fluid PMN percentage. CONCLUSIONS The sensitivity and specificity of the LE strip in the diagnosis of PJI are quite high, which means the LE strip might be used as an alternative to diagnose PJI in clinical practice.
Conradie, Wilhelmus Jacobus; Gebremariam, Fekade Admassu
2015-01-01
To determine the sensitivity and specificity of computed tomography (CT) esophagography in diagnosing penetrating esophageal and hypopharyngeal injuries in trauma patients and to see if it can be used as the only imaging method in diagnosing these injuries. The confidence of radiologists using only CT esophagography was also measured. A prospective cross-sectional analytic study was done on haemodinamically stable patients requiring multidetector CT after external penetrating neck or chest trauma. Each patient was given oral contrast consisting of 50 ml 50% iohexol solution, within 5 min of commencement of the CT examination and in the supine position. An attempt was made to confirm all CT esophagography findings with at least one secondary method. Images were evaluated separately by two general departmental radiologists who were blinded to the results of the confirmation method. Between December 2012 and November 2014, 102 patients were included, of which 93 (91.2%) were male. Stab wounds were responsible for 85.3% (n=87) of penetrating wounds. Ninety-four patients (92.2%) had CT angiography (CTA) in conjunction with CT esophagography. There were 20 confirmed upper digestive tract injuries; 11 (55.0%) in the hypopharynx and 9 (45.0%) in the esophagus. With the exception of one case, all upper digestive tract injuries were diagnosed using only CT esophagography. No upper digestive tract injuries were correctly identified in 70 and 75 out of 82 true negative cases respectively, suggesting a sensitivity of 95.0% for both radiologists and specificity of 85.4% and 91.5% for CT esophagography. A number of false positive diagnoses were reported when CT esophagography was done in conjunction with CTA, resulting in a positive predictive value of 61.3% and 79.1% for this technique. Reviewers were positive to very confident about the CT esophagography findings in 90.0% and 100% of patients with injuries and 79.0% and 87.0%, respectively, in the no injury group. CT esophagography is reliable in diagnosing penetrating upper digestive tract injuries. In conjunction with CTA, false positive findings may occur. Radiologists were generally positive to very confident about their CT esophagography findings, not needing further imaging in more than 60% of cases. Copyright © 2015 Elsevier Inc. All rights reserved.
Flores Mateo, Gemma; Conejero, Jaume; Grenzner Martinel, Elisabet; Baba, Zeki; Dicono, Susana; Echasabal, Mildrey; Gonzalo Santos, Concepción; Aliaga, Arantxa; Barredo, María; Ruiz, Luis; Carrau, Montserrat
2010-07-01
To determine the validity of the rapid antigen test for the diagnoses of acute pharyngitis caused by group A beta-haemolytic Streptococcus (GABHS) compared with culture. Observational study of a consecutive sample of paediatric patients. Two primary care centres (PCC) from the metropolitan area of Barcelona. Children aged 1-14 years with sore throat of no more than 5 days duration were chosen at PCC. Oropharyngeal samples were collected from tonsillar bed and posterior pharynx. A rapid diagnostic test was performed, as well as a throat culture. A total of 211 patients were studied. The overall prevalence of pharyngitis due to Streptococcus was 34.1%. Compared with the throat culture, the sensitivity of the rapid test was 90.3% (95% CI: 81.0-96.0), the specificity was 78.4% (95% CI: 70.6-84.9). The percentage of false negatives was 9.7% and the false positives was 21.6%. Spectrum bias was present, inasmuch as the rapid test sensitivity increased with Centor scores. The diagnostic value of a rapid antigen test for the diagnosis of streptococcal pharyngitis in paediatric patients at PCC is high. However, the percentage of false positives and negatives is too high, and also the sensitivity is too low in patients with fewer symptoms to support the use of rapid antigenic test without culture confirmation and bacterial sensitivity test. 2009 Elsevier España, S.L. All rights reserved.
Grati, Francesca R; Malvestiti, Francesca; Grimi, Beatrice; Gaetani, Elisa; Di Meco, Anna Maria; Trotta, Anna; Liuti, Rosaria; Chinetti, Sara; Dulcetti, Francesca; Ruggeri, Anna Maria; Agrati, Cristina; Frascoli, Giuditta; Milani, Silvia; De Toffol, Simona; Martinoni, Lorenza; Paganini, Silvia; Marcato, Livia; Maggi, Federico; Simoni, Giuseppe
2013-05-01
Karyotyping on chorionic villous samples (CVS) includes the analysis of both cytotrophoblast (STC) and mesenchyme (LTC). This approach requires complex laboratory organization and trained technicians. The introduction of quantitative fluorescent polymerase chain reaction (QF-PCR) instead of conventional karyotyping in low-risk pregnancies opened its application in CVS analysis. Discordant QF-PCR and CVS cytogenetic results were reported, and strategies for CVS analysis were introduced to minimize this risk. The possibility to substitute the STC with QF-PCR was reported. The aim of this study is to evaluate benefits and limitations of the approach QF-PCR + LTC compared with the traditional method STC + LTC and to quantify the associated risks of false results. This study is based on a retrospective cytogenetic audit of CVS results (n = 44 727) generated by the STC + LTC analytic approach. False-negative risks related to true fetal mosaicism type IV, imprinting syndromes and maternal contamination in LTC were calculated. Compared with STC + LTC, QF-PCR + LTC approach is associated with a cumulative false-negative risk of ~1/3100-1/4400. Costs and reporting time of STC in a high-throughput cytogenetic lab are similar to a CE-IVD marked QF-PCR analysis. These results should be clearly highlighted in the pre-test counseling and extensively discussed with the couple prior to testing for informed consent. © 2013 John Wiley & Sons, Ltd.
Emergency ultrasound in the acute assessment of haemothorax
Brooks, A; Davies, B; Smethhurst, M; Connolly, J
2004-01-01
Aims: To evaluate thoracic ultrasound for the detection of haemothorax in patients with thoracic trauma against established investigations. Methods: Thoracic ultrasound was performed as an extension of the standard focused assessment with sonography for trauma (FAST) protocol used at the Queen's Medical Centre for the assessment of adult patients with torso trauma. Fluid was sought in both pleural cavities using a hand portable ultrasound system by one of two non-radiologists trained in FAST. Findings were compared against subsequent investigations/procedures performed at the discretion of the attending emergency physician—supine chest radiography, intercostal drain, computed tomography, or thoracotomy. The sensitivity of the technique and the time taken to diagnosis for each investigation were recorded. Results: Sixty one patients, 54 (89%) after blunt trauma, underwent thoracic ultrasound evaluation during the study. Twelve patients had a haemothorax detected by ultrasound and confirmed by computed tomography or by tube thoracostomy. Four haemothoraces detected on ultrasound were not apparent on trauma chest radiography. There were 12 true positives, 48 true negatives, no false positives, and one false negative scan. The sensitivity of ultrasound was 92% and specificity 100% with a positive predictive value of 100% and negative predictive value 98% for the detection of haemothorax after trauma. Conclusions: Emergency ultrasound of the chest performed as part of the primary survey of the traumatised patient can rapidly and accurately diagnose haemothorax and is a valuable tool to augment the immediate clinical assessment of these patients. PMID:14734374
Krüger, Carsten; Malleyeck, Isaack
2010-05-01
With 700,000 to 1.5 million new cases annually, congenital syphilis remains a major infectious cause of morbidity and mortality in neonates, infants and children in resource-poor countries. We therefore analyzed the extent of congenital syphilis in the pediatric patient population at our rural hospital in Tanzania. For this retrospective analysis, from January 1, 1998 to August 31, 2000, all cases of congenital syphilis were collected from the medical records of the neonatal and pediatric department at Haydom Lutheran Hospital in rural northern Tanzania. Age, sex, weight, clinical signs and symptoms, venereal disease research laboratory (VDRL) results of mother and/or child, hemoglobin concentration, treatment, and outcome were recorded and analyzed. Fourteen neonates and infants were included. The earlier the diagnosis, the more it rested on maternal data because the presentation of neonatal congenital syphilis resembled neonatal sepsis. Syphilitic skin lesions were only seen in the post-neonatal age group. VDRL results were positive in 11 of the 14 mothers, and in 4 of the infants. Anemia was common in older infants. No patient showed signs of central nervous system involvement. Two patients died, and the remaining were cured after standard treatment with procaine penicillin. Highlighting the variable picture of congenital syphilis, this report demonstrates how difficult it is to make a correct diagnosis by solely history and clinical presentation in a resource-poor setting. Hence false-positive and false-negative diagnoses are common, and clinicians have to maintain a high index of suspicion in diagnosing congenital syphilis. Therefore, an important approach to control and finally eliminate congenital syphilis as a major public health problem will be universal on-site syphilis screening of all pregnant women at their first antenatal visit and immediate treatment for those who test positive.
Pletscher, Mark; Walker, Simon; Moschetti, Karine; Pinget, Christophe; Wasserfallen, Jean-Blaise; Greenwood, John P; Schwitter, Juerg; Girardin, François R
2016-07-01
The aim of this study was to assess the cost-effectiveness of eight common diagnostic work-up strategies for coronary heart disease (CHD) in patients with stable angina symptoms in Switzerland. A decision analytical model was used to perform a cost-effectiveness comparison of eight common multitest strategies to diagnose CHD using combinations of four diagnostic techniques: exercise treadmill test (ETT), single-photon emission computed tomography (SPECT), cardiac magnetic resonance imaging (CMR), and coronary angiography (CA). We used a Markov state transition model to extrapolate the results over a life-time horizon, from a third-party payer perspective. We used a CHD prevalence rate of 39% in patients and a base-case scenario with 60-year-old male patients with intermediate symptom severity Canadian Cardiovascular Society grading of angina pectoris 2 and at least one cardiovascular (CV) risk factor but without a history of myocardial infarction and without need for revascularization. Among the eight work-up strategies, one strategy was dominant, i.e. least costly and most effective: ETT followed by CMR if the ETT result was inconclusive and then CA if the CMR result was positive or inconclusive. The CMR features a favourable balance between false-negative diagnoses, associated with an elevated risk of CV events, and false-positive diagnoses, leading to unnecessary CA and related mortality. Key parameters guiding the diagnostic strategy are the prevalence of CHD in patients with angina symptoms and the diagnostic costs of CA and CMR. Cardiac magnetic resonance imaging appears to be a cost-effective work-up strategy compared with other regimens using SPECT or direct CA. Cardiac magnetic resonance imaging should be more widely recommended as a diagnostic procedure for patients with suspected angina symptoms.
Abrahamyan, Lusine; Sahakyan, Yeva; Chung, Suzanne; Pechlivanoglou, Petros; Bielecki, Joanna; Carcone, Steven M; Rac, Valeria E; Fitzpatrick, Michael; Krahn, Murray
2018-01-09
Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder. In-laboratory, overnight type I polysomnography (PSG) is the current "gold standard" for diagnosing OSA. Home sleep apnea testing (HSAT) using portable monitors (PMs) is an alternative testing method offering better comfort and lower costs. We aimed to systematically review the evidence on diagnostic ability of type IV PMs compared to PSG in diagnosing OSA. Participants: patients ≥16 years old with symptoms suggestive of OSA;intervention: type IV PMs (devices with < 2 respiratory channels); comparator: in-laboratory PSG; outcomes: diagnostic accuracy measures;studies: cross-sectional, prospective observational/experimental/quasi-experimental studies; information sources: MEDLINE and Cochrane Library from January 1, 2010 to May 10, 2016. All stages of review were conducted independently by two investigators. We screened 6054 abstracts and 117 full-text articles to select 24 full-text articles for final review. These 24 studies enrolled a total of 2068 patients with suspected OSA and evaluated 10 different PMs with one to six channels. Only seven (29%) studies tested PMs in the home setting. The mean difference (bias) between PSG-measured and PM-measured apnea-hypopnea index (AHI) ranged from - 14.8 to 10.6 events/h. At AHI ≥ 5 events/h, the sensitivity of type IV PMs ranged from 67.5-100% and specificity ranged from 25 to 100%. While current evidence is not very strong for the stand-alone use of level IV PMs in clinical practice, they can potentially widen access to diagnosis and treatment of OSA. Policy recommendations regarding HSAT use should also consider the health and broader social implications of false positive and false negative diagnoses.
Faciszewski, T; Broste, S K; Fardon, D
1997-10-01
The purpose of the present study was to evaluate the accuracy of data regarding diagnoses of spinal disorders in administrative databases at eight different institutions. The records of 189 patients who had been managed for a disorder of the lumbar spine were independently reviewed by a physician who assigned the appropriate diagnostic codes according to the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). The age range of the 189 patients was seventeen to eighty-four years. The six major diagnostic categories studied were herniation of a lumbar disc, a previous operation on the lumbar spine, spinal stenosis, cauda equina syndrome, acquired spondylolisthesis, and congenital spondylolisthesis. The diagnostic codes assigned by the physician were compared with the codes that had been assigned during the ordinary course of events by personnel in the medical records department of each of the eight hospitals. The accuracy of coding was also compared among the eight hospitals, and it was found to vary depending on the diagnosis. Although there were both false-negative and false-positive codes at each institution, most errors were related to the low sensitivity of coding for previous spinal operations: only seventeen (28 per cent) of sixty-one such diagnoses were coded correctly. Other errors in coding were less frequent, but their implications for conclusions drawn from the information in administrative databases depend on the frequency of a diagnosis and its importance in an analysis. This study demonstrated that the accuracy of a diagnosis of a spinal disorder recorded in an administrative database varies according to the specific condition being evaluated. It is necessary to document the relative accuracy of specific ICD-9-CM diagnostic codes in order to improve the ability to validate the conclusions derived from investigations based on administrative databases.
Kattah, Jorge C; Talkad, Arun V; Wang, David Z; Hsieh, Yu-Hsiang; Newman-Toker, David E
2009-11-01
Acute vestibular syndrome (AVS) is often due to vestibular neuritis but can result from vertebrobasilar strokes. Misdiagnosis of posterior fossa infarcts in emergency care settings is frequent. Bedside oculomotor findings may reliably identify stroke in AVS, but prospective studies have been lacking. The authors conducted a prospective, cross-sectional study at an academic hospital. Consecutive patients with AVS (vertigo, nystagmus, nausea/vomiting, head-motion intolerance, unsteady gait) with >or=1 stroke risk factor underwent structured examination, including horizontal head impulse test of vestibulo-ocular reflex function, observation of nystagmus in different gaze positions, and prism cross-cover test of ocular alignment. All underwent neuroimaging and admission (generally <72 hours after symptom onset). Strokes were diagnosed by MRI or CT. Peripheral lesions were diagnosed by normal MRI and clinical follow-up. One hundred one high-risk patients with AVS included 25 peripheral and 76 central lesions (69 ischemic strokes, 4 hemorrhages, 3 other). The presence of normal horizontal head impulse test, direction-changing nystagmus in eccentric gaze, or skew deviation (vertical ocular misalignment) was 100% sensitive and 96% specific for stroke. Skew was present in 17% and associated with brainstem lesions (4% peripheral, 4% pure cerebellar, 30% brainstem involvement; chi(2), P=0.003). Skew correctly predicted lateral pontine stroke in 2 of 3 cases in which an abnormal horizontal head impulse test erroneously suggested peripheral localization. Initial MRI diffusion-weighted imaging was falsely negative in 12% (all <48 hours after symptom onset). Skew predicts brainstem involvement in AVS and can identify stroke when an abnormal horizontal head impulse test falsely suggests a peripheral lesion. A 3-step bedside oculomotor examination (HINTS: Head-Impulse-Nystagmus-Test-of-Skew) appears more sensitive for stroke than early MRI in AVS.
Gaur, Aditya H; Flynn, Patricia M; Heine, Daniel J; Giannini, Mary Anne; Shenep, Jerry L; Hayden, Randall T
2005-05-01
Current methods for in situ diagnosis of catheter-related bloodstream infections require concurrent collection of central venous catheter (CVC) and peripheral vein (PV) blood cultures. Both the pain and inconvenience of PV cultures are undesirable. A prospective study was conducted (August 2002 to March 2004) to assess the accuracy of diagnosing catheter-related bloodstream infections based on the difference in time to detection of blood cultures drawn concurrently from 2 lumens of a multilumen CVC. This difference in time to detection between 2 lumens was compared with results of the standard criterion with paired CVC and PV blood cultures. Twenty-one infectious episodes were categorized as catheter-related bloodstream infections and 38 as non-catheter-related bloodstream infections. With a cutoff in difference in time to detection between 2 lumens of > or =180 minutes, the sensitivity of this test to diagnose a catheter-related bloodstream infection was 61% (95% confidence interval, 39-80%) and the specificity was 94% (95% confidence interval, 82-99%). In 4 of 7 episodes with false-negative results, the colony counts in cultures from both lumens were >400 colony-forming units/mL (maximal value reported), indicating the limitation of this method when both lumens of the catheter are colonized. With the pretest probability of catheter-related bloodstream infections ranging from 28% to 54%, the positive predictive value of a difference in time to detection between 2 lumens of > or =180 minutes for diagnosis of catheter-related bloodstream infections ranged from 81% to 93% and the negative predictive value ranged from 67% to 86%. Within the context of its limitations, this novel method provides an alternative for diagnosing catheter-related bloodstream infections among patients with a CVC, without PV cultures.
Transperineal prostate biopsy with ECHO-MRI fusion. Biopsee system. Initial experience.
Romero-Selas, E; Cuadros, V; Montáns, J; Sánchez, E; López-Alcorocho, J M; Gómez-Sancha, F
2016-06-01
The aim of this study is to present our initial experience with the stereotactic echo-MRI fusion system for diagnosing prostate cancer. Between September 2014 and January 2015, we performed 50 prostate biopsies using the stereotactic echo-MRI fusion system. The 3-Tesla multiparameter MR images were superimposed using this image fusion system on 3D echo images obtained with the Biopsee system for the exact locating of areas suspected of prostate cancer. The lesions were classified using the Prostate Imaging Report and Date System. We assessed a total of 50 patients, with a mean age of 63 years (range, 45-79), a mean prostate-specific antigen level of 8 ng/mL (range, 1.9-20) and a mean prostate volume of 52mL (range, 12-118). Prostate cancer was diagnosed in 69% of the patients and intraepithelial neoplasia in 6%. The results of the biopsy were negative for 24% of the patients. The results of the biopsy and MRI were in agreement for 62% of the patients; however, 46% also had a tumour outside of the suspicious lesion. We diagnosed 46% anterior tumours and 33% apical tumours. One patient had a haematuria, another had a haematoma and a third had acute urine retention. Multiparametric prostatic MRI helps identify prostate lesions suggestive of cancer. The Biopsee echo-MRI fusion system provides for guided biopsy and increases the diagnostic performance, reducing the false negatives of classical biopsies and increasing the diagnosis of anterior tumours. Transperineal access minimises the risk of prostatic infection and sepsis. Copyright © 2015 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.
The false-negative rate of sentinel node biopsy in patients with breast cancer: a meta-analysis
Pesek, Sarah; Ashikaga, Taka; Krag, Lars Erik; Krag, David
2012-01-01
Background/Purpose In sentinel node surgery for breast cancer, procedural accuracy is assessed by calculating the false-negative rate. It is important to measure this since there are potential adverse outcomes from missing node metastases. We performed a meta-analysis of published data to assess which method has achieved the lowest false-negative rate. Methods We found 3588 articles concerning sentinel nodes and breast cancer published from 1993 through mid-2011; 183 articles met our inclusion criteria. The studies described in these 183 articles included a total of 9306 patients. We grouped the studies by injection material and injection location. The false-negative rates were analyzed according to these groupings and also by the year in which the articles were published. Results There was significant variation in the false-negative rate over time with a trend to higher rates over time. There was significant variation related to injection material. The use of blue dye alone was associated with the highest false-negative rate. Inclusion of a radioactive tracer along with blue dye resulted in a significantly lower false-negative rate. Although there were variations in the false-negative rate according to injection location, none were significant. This meta-analysis also indicates a significant change over time in the false-negative rate. Discussion/Conclusions The use of blue dye should be accompanied by a radioactive tracer to achieve a significantly lower false-negative rate. Location of injection did not have a significant impact on the false-negative rate. Given the limitations of acquiring appropriate data, the false-negative rate should not be used as a metric for training or quality control. PMID:22569745
SFE/SFHTA/AFCE consensus on primary aldosteronism, part 4: Subtype diagnosis.
Bardet, Stéphane; Chamontin, Bernard; Douillard, Claire; Pagny, Jean-Yves; Hernigou, Anne; Joffre, Francis; Plouin, Pierre-François; Steichen, Olivier
2016-07-01
To establish the cause of primary aldosteronism (PA), it is essential to distinguish unilateral from bilateral adrenal aldosterone secretion, as adrenalectomy improves aldosterone secretion and controls hypertension and hypokalemia only in the former. Except in the rare cases of type 1 or 3 familial hyperaldosteronism, which can be diagnosed genetically and are not candidates for surgery, lateralized aldosterone secretion is diagnosed on adrenal CT or MRI and adrenal venous sampling. Postural stimulation tests and (131)I-norcholesterol scintigraphy have poor diagnostic value and (11)C-metomidate PET is not yet available. We recommend that adrenal CT or MRI be performed in all cases of PA. Imaging may exceptionally identify adrenocortical carcinoma, for which the surgical objectives are carcinologic, and otherwise shows either normal or hyperplastic adrenals or unilateral adenoma. Imaging alone carries a risk of false positives in patients over 35 years of age (non-aldosterone-secreting adenoma) and false negatives in all patients (unilateral hyperplasia). We suggest that all candidates for surgery over 35 years of age undergo adrenal venous sampling, simultaneously in both adrenal veins, without ACTH stimulation, to confirm the unilateral form of the hypersecretion. Sampling results should be confirmed on adrenal vein cortisol assay showing a concentration at least double that found in peripheral veins. Aldosterone secretion should be considered lateralized when aldosterone/cortisol ratio on the dominant side is at least 4-fold higher than contralaterally. Published by Elsevier Masson SAS.
Diagnostic testing of dogs for food hypersensitivity.
Jeffers, J G; Shanley, K J; Meyer, E K
1991-01-15
Thirteen food-allergic dogs were studied to evaluate the efficacy of feeding a commercially available egg and rice diet, intradermal skin testing, and serologic testing by ELISA for diagnosing and/or characterizing food hypersensitivity. Feeding of a home-cooked whole lamb meat and rice diet for 3 weeks, followed by challenge with each dog's regular diet, served as the standard for diagnosing food hypersensitivity. Each dog underwent provocative testing with 6 individual ingredients to determine as many of its dietary allergens as possible. Prior to skin testing and serologic testing by ELISA, most dogs had been recently exposed to the offending diet and subsequently manifested clinical signs of allergy. All dogs that tolerated the aforementioned commercial diet were exposed to it for at least 7 weeks; 84.6% of food-hypersensitive dogs ate the commercial diet with impunity. Of the 2 reactors to the commercial diet, only 1 became pruritic in response to provocation testing with chicken eggs. Low sensitivity and high specificity were found for skin testing and the ELISA, indicating a lack of true- and false-positive reactions. Neither the positive nor negative predictive values adequately predicted positive and negative reactions, respectively, for either test. On the basis of these results, the commercial diet, skin testing, and anti-IgE ELISA cannot replace an owner-prepared food elimination diet for food hypersensitivity testing in dogs.
2011-01-01
Background The botanical relation between grass and cereal grains may be relevant when diagnosing food allergy to cereals. The aim was to investigate the diagnostic specificity of skin prick test (SPT) and specific immunoglobulin E (sIgE) tests to cereals and peanut in grass pollen allergic subjects without history of, and clinically reactions to foods botanically related to grass. Methods 70 subjects (41 females; mean age 32 years) and 20 healthy controls (13 females; mean age 24 years) were tested by open food challenge (OFC) with cereals and peanut. SPT and sIgE both with Immulite® (Siemens) and ImmunoCAP® (Phadia) to grass and birch pollen, cereals, peanut and bromelain were performed. Results Of the 65 OFC-negative subjects 29-46% (SPT, depending on cut-off), 20% (Immulite) and 38% (ImmunoCAP) had positive results to one or more of the foods tested. Controls were negative in all tests. Cross-reactive carbohydrate determinants (CCD) as evidenced by reaction to bromelain could explain only a minority of the measured IgE-sensitizations. Conclusion Grass pollen allergic patients with documented food tolerance to cereals and peanut may express significant sensitization. False-positive cereal or peanut allergy diagnoses may be a quantitatively important problem both in routine clinical work and epidemiological studies. PMID:22409998
DOE Office of Scientific and Technical Information (OSTI.GOV)
Caturelli, Eugenio; Biasini, Elisabetta; Bartolucci, Francesca
2002-08-15
Purpose: To evaluate the utility of a second ultrasound-guided fine-needle biopsy of liver nodules thought to be hepatocellular carcinoma when the original biopsy has failed to provide a reliable diagnosis. Methods: Thirty-seven cirrhotic patients underwent ultrasound-guided fine-needle biopsy of liver nodules that were subsequently diagnosed as hepatocellular carcinoma. Each biopsy involved a single puncture with a 20 G cutting needle, which yielded pathologic material used both for cytologic and histologic studies. In 23 cases (mean diameter of nodules 48 mm) the biopsy furnished exclusively necrotic material (non-diagnostic subgroup); in the other 14 cases (mean diameter 26 mm) the biopsy yieldedmore » no neoplastic elements (false-negative subgroup). All 37 nodules were subjected to repeat biopsies performed in the same manner. Results: The repeat biopsies provided a diagnosis of hepatocellular carcinoma in six of the 23 patients from the non-diagnostic subgroup and in seven of the 14 in the false-negative subgroup. Overall, repeat biopsy produced a diagnostic gain of 35.1%. Conclusion: The chance of success with repeat biopsy of hepatocellular carcinoma is limited and may depend to some extent on the characteristics of the lesions (i.e., areas of necrosis in large nodules, well-differentiated cellular populations in small ones)« less
Usefulness and safety of biliary percutaneous transluminal forceps biopsy (PTFB): our experience.
Ierardi, Anna Maria; Mangini, Monica; Fontana, Federico; Floridi, Chiara; De Marchi, Giuseppe; Petrillo, Mario; Capasso, Raffaella; Chini, Claudio; Cocozza, Eugenio; Cuffari, Salvatore; Segato, Sergio; Rotondo, Antonio; Carrafiello, Gianpaolo
2014-03-01
To evaluate the usefulness and safety of percutaneous transluminal forceps biopsy in patients suspected of having a malignant biliary obstruction. Forty consecutive patients (21 men and 19 women; mean age, 71.9 years) underwent forceps biopsy through percutaneous transhepatic biliary access performed to drain bile. Lesions involved the common bile duct (n 8), common hepatic duct (n 18), hilum (n 6), ampullary segment of the common bile duct (n 8) and were biopsied with 7-F biopsy forceps. Final diagnosis was confirmed with pathologic findings at surgery, or clinical and radiologic follow-up. Twenty-one of 40 biopsies resulted in correct diagnosis of malignancy. Thirteen biopsy diagnosis were proved to be true-negative. There were six false-negative and no false-positive diagnoses. Sensitivity, specificity and accuracy in aspecific biliary obstructions were 85%, 100% and 88,7% respectively. Sensitivity of biopsy in malignancies was higher than in benign obstructions (100% vs 68,4%, CI = 95%). Sensitivity was lower in the hilum tract and in the common bile duct than in other sites (CI = 95%). No major complications related to biopsy procedures occurred. Percutaneous transluminal forceps biopsy is a safe procedure, easy to perform through a transhepatic biliary drainage tract, providing high accuracy in the diagnosis of malignant biliary obstructions.
New monoclonal antibody-based test for Helicobacter pylori urease in gastric tissue.
Kim, Do Hyun; Kim, Ho Dong; Park, Hyeuk; Choi, Seung; Beom, Jae Won; Kim, Woo Jong; Park, Chang Kook; Lee, Young Jik; Park, Ju Young; Kim, Hyung Rag; Park, Chul; Joo, Young Eun; Jung, Young Do
2016-01-01
To evaluate a new monoclonal antibody for Helicobacter pylori urease in gastric tissue. A total of 107 volunteers were enrolled. All subjects underwent a (13)C-urea breath test and esophagogastroduodenoscopy. Gastric aspirates were analyzed for pH and ammonia. Six biopsy specimens in the gastric antrum and body were obtained for a rapid urease test and histology. The new monoclonal antibody-based H. pylori urease test (HPU) was performed to rapidly and qualitatively detect urease in two biopsy specimens. H. pylori infection was diagnosed in 73 subjects. The sensitivity and specificity of the HPU was 89% and 74%, respectively. The subjects were divided into two groups: one with true-positive and true-negative HPU results (n = 90) and the other with false-positive and false-negative HPU results (n = 17). Across all subjects, ammonia levels were 900.5 ± 646.7 and 604.3 ± 594.3 μmol/L (p > 0.05), and pH was 3.37 ± 1.64 and 2.82 ± 1.51 (p > 0.05). Sensitivity was higher in the presence of atrophic gastritis or intestinal metaplasia. HPU detected H. pylori in approximately 10 min. Gastric aspirate ammonia and pH levels did not affect the test results. Sensitivity was good in the presence of atrophic gastritis or intestinal metaplasia.
Navarrete-Dechent, Cristián; Bajaj, Shirin; Marghoob, Ashfaq A; Marchetti, Michael A
2015-06-01
Dermatophytoses are common skin infections. Traditional diagnostic tests such as skin scrapings for light microscopy examination, fungal cultures and biopsies remain imperfect due to false-negative test results, cost, time required to perform the procedure, time delays in test results and/or a requirement for an invasive procedure. Herein, we present a case of an 80-year-old female whose tinea incognito was non-invasively diagnosed within seconds using handheld reflectance confocal microscopy (RCM). As non-invasive skin imaging continues to improve, we expect light-based office microscopy to be replaced with technologies such as RCM, which has multiple and continually expanding diagnostic applications. © 2015 Blackwell Verlag GmbH.
Bae, Y J; Jeon, Y J; Choi, B S; Koo, J-W; Song, J-J
2017-06-01
Typewriter tinnitus, a symptom characterized by paroxysmal attacks of staccato sounds, has been thought to be caused by neurovascular compression of the cochlear nerve, but the correlation between radiologic evidence of neurovascular compression of the cochlear nerve and symptom presentation has not been thoroughly investigated. The purpose of this study was to examine whether radiologic evidence of neurovascular compression of the cochlear nerve is pathognomonic in typewriter tinnitus. Fifteen carbamazepine-responding patients with typewriter tinnitus and 8 control subjects were evaluated with a 3D T2-weighted volume isotropic turbo spin-echo acquisition sequence. Groups 1 (16 symptomatic sides), 2 (14 asymptomatic sides), and 3 (16 control sides) were compared with regard to the anatomic relation between the vascular loop and the internal auditory canal and the presence of neurovascular compression of the cochlear nerve with/without angulation/indentation. The anatomic location of the vascular loop was not significantly different among the 3 groups (all, P > .05). Meanwhile, neurovascular compression of the cochlear nerve on MR imaging was significantly higher in group 1 than in group 3 ( P = .032). However, considerable false-positive (no symptoms with neurovascular compression of the cochlear nerve on MR imaging) and false-negative (typewriter tinnitus without demonstrable neurovascular compression of the cochlear nerve) findings were also observed. Neurovascular compression of the cochlear nerve was more frequently detected on the symptomatic side of patients with typewriter tinnitus compared with the asymptomatic side of these patients or on both sides of control subjects on MR imaging. However, considering false-positive and false-negative findings, meticulous history-taking and the response to the initial carbamazepine trial should be regarded as more reliable diagnostic clues than radiologic evidence of neurovascular compression of the cochlear nerve. © 2017 by American Journal of Neuroradiology.
Does imprint cytology improve the accuracy of transrectal prostate needle biopsy?
Sayar, Hamide; Bulut, Burak Besir; Bahar, Abdulkadir Yasir; Bahar, Mustafa Remzi; Seringec, Nurten; Resim, Sefa; Çıralık, Harun
2015-02-01
To evaluate the accuracy of imprint cytology of core needle biopsy specimens in the diagnosis of prostate cancer. Between December 24, 2011 and May 9, 2013, patients with an abnormal DRE and/or serum PSA level of >2.5 ng/mL underwent transrectal prostate needle biopsy. Samples with positive imprint cytology but negative initial histologic exam underwent repeat sectioning and histological examination. 1,262 transrectal prostate needle biopsy specimens were evaluated from 100 patients. Malignant imprint cytology was found in 236 specimens (18.7%), 197 (15.6%) of which were confirmed by histologic examination, giving an initial 3.1% (n = 39) rate of discrepant results by imprint cytology. Upon repeat sectioning and histologic examination of these 39 biopsy samples, 14 (1.1% of the original specimens) were then diagnosed as malignant, 3 (0.2%) as atypical small acinar proliferation (ASAP), and 5 (0.4%) as high-grade prostatic intraepithelial neoplasia (HGPIN). Overall, 964 (76.4%) specimens were negative for malignancy by imprint cytology. Seven (0.6%) specimens were benign by cytology but malignant cells were found on histological evaluation. On imprint cytology examination, nonmalignant but abnormal findings were seen in 62 specimens (4.9%). These were all due to benign processes. After reexamination, the accuracy, sensitivity, specificity, positive predictive value, negative predictive value, false-positive rate, false-negative rate of imprint preparations were 98.1, 96.9, 98.4, 92.8, 99.3, 1.6, 3.1%, respectively. Imprint cytology is valuable tool for evaluating TRUS-guided core needle biopsy specimens from the prostate. Use of imprint cytology in combination with histopathology increases diagnostic accuracy when compared with histopathologic assessment alone. © 2014 Wiley Periodicals, Inc.
Purpose/Objectives To collect biological samples from subjects with prostate cancer to improve the accuracy of screening tests, identify markers that will predict how aggressive prostate cancers can be, and provide accurate information about how rapidly prostate cancer can worsen. Research Design/Plan Men with the following criteria will be consented for this protocol. 1.) ≥5 years post prostate cancer diagnosis, between the ages of 30 and 99 years of age (OR). (Targeted recruits.) 2.) Diagnosed with prostate cancer with a Gleason’s score ≥ 4+3=7, or 3+3 with survivorship of 5 years, or is positive for metastatic disease, or recurrence or has an unexplained increase in their serum PSA after treatment. (Targeted recruits.) 3.) Diagnosed with prostate cancer in the past in whom follow-up is available. Diagnostic and prognostic data will be collected as well as approximately 2 tablespoons of blood samples will be drawn from a vein in the subjects arm for processing and storage in the GU Tissue Bank (“Tissue Bank and Data Base for Urologic Diseases” HSC20050234H). The study involves a single visit with annual telephone follow-up interviews to update the treatment and prognostic data. Methods Potential subjects will be identified through recruitment at clinics, through advertisement, at prostate cancer lectures, support group meetings, and by referral. Once a potential subject has been identified, they will be informed about the study and the inclusion criteria to see if they qualify. If the subject qualifies and provides informed consent, the study staff will collect and record demographic and disease information and completion of the AUA questionnaire. The subjects will be called annually to updates by the research staff. Clinical Relevance Cancer statistics from the early 1990s reflect both a decline in prostate cancer mortality and a “downstaging” of the disease at the time of diagnosis. Thus, the number of men who have metastases at the time of diagnosis of their initial diagnosis of prostate cancer has decreased in parallel with a decline in mortality. These favorable statistical trends followed the introduction of prostate specific antigen (PSA) as a screening assay for prostate cancer in the late 1980s and imply that earlier diagnosis and treatment provide benefit to the population. However, large scale screening activity must be carefully scrutinized for less desirable outcomes such as “over diagnosis” of biologically indolent disease and failure to diagnose aggressive disease. When screening techniques are introduced into large populations, the number of false positives and false negatives is quite high even when the specificity of a test approaches 95%. Men who are “false positives” needlessly undergo biopsy and the associated anxiety. The detection rate using PSA alone is approximately 25%. The information gained from this study may potentially increase the sensitivity and specificity of prostate cancer screenings, eliminate many of the false negatives and help detect early relapse of disease.
Diagnosis of dementia--automatic quantification of brain structures.
Engedal, Knut; Brækhus, Anne; Andreassen, Ole A; Nakstad, Per Hj
2012-08-21
The aim of the present study was to examine the usefulness of a fully automatic quantification of brain structures by means of magnetic resonance imaging (MRI) for diagnosing dementia of the Alzheimer's type (DAT). MRI scans of the brains of 122 patients, referred to a memory clinic, were analysed using Neuroquant® software, which quantifies the volume of various brain structures. Clinical diagnoses were made by two doctors without knowledge of the MRI results. We performed Receiver Operating Characteristic analyses and calculated the area under the curve (AUC). A value of 1 means that all ill patients have been diagnosed as diseased and no patient has been falsely diagnosed as diseased. The mean age of the patients was 67.2 years (SD 10.5 years), 60 % were men, 63 had DAT, 24 had another type of dementia, 25 had mild cognitive impairment (MCI) and ten had subjective cognitive impairment (SCI). In the comparison between DAT patients and patients with SCI or MCI, seven of eleven volumes were significantly larger than AUC 0.5. Positive and negative likelihood ratios were less than 5 and more than 0.2, respectively, for the best limit values of the volumes. Apart from the cerebellum (AUC 0.67), none of the brain structures was significantly different from AUC 0.5 in patients with dementia conditions other than dementia Alzheimer's type. MRI scans with Neuroquant analyses cannot be used alone to distinguish between persons with dementia of Alzheimer's type and persons without dementia.
Engelman, Daniel; Mataika, Reapi L; Ah Kee, Maureen; Donath, Susan; Parks, Tom; Colquhoun, Samantha M; Carapetis, Jonathan R; Kado, Joseph H; Steer, Andrew C
2017-08-01
Echocardiographic screening is under consideration as a disease control strategy for rheumatic heart disease (RHD). However, clinical outcomes of young people with screening-detected RHD are unknown. We aimed to describe the outcomes for a cohort with screening-detected RHD, in comparison to patients with clinically-diagnosed RHD. A retrospective cohort study included all young people with screening-detected RHD in the Central Division of Fiji in the primary cohort. Screen-negative and clinically-diagnosed comparison groups were matched 1:1 to the primary cohort. Data were collected on mortality, clinical complications and healthcare utilisation from the electronic and paper health records and existing databases. Seventy participants were included in each group. Demographic characteristics of the groups were similar (median age 11years, 69% female, median follow-up 7years). There were nine (12.9%) RHD-related deaths in the clinically-diagnosed group and one (1.4%) in the screening-detected group (Incident Rate Ratio: 9.6, 95% CI 1.3-420.6). Complications of RHD were observed in 39 (55.7%) clinically-diagnosed cases, four (20%) screening-detected cases and one (1.4%) screen-negative case. There were significant differences in the cumulative complication curves of the groups (p<0.001). Rates of admission and surgery were highest in the clinically-diagnosed group, and higher in the screening-detected than screen-negative group. Young people with screening-detected RHD have worse health outcomes than screen-negative cases in Fiji. The prognosis of clinically-diagnosed RHD remains poor, with very high mortality and complication rates. Further studies in other settings will inform RHD screening policy. Comprehensive control strategies are required for disease prevention. Copyright © 2017 Elsevier B.V. All rights reserved.
A Closer Look at Self-Reported Suicide Attempts: False Positives and False Negatives
ERIC Educational Resources Information Center
Ploderl, Martin; Kralovec, Karl; Yazdi, Kurosch; Fartacek, Reinhold
2011-01-01
The validity of self-reported suicide attempt information is undermined by false positives (e.g., incidences without intent to die), or by unreported suicide attempts, referred to as false negatives. In a sample of 1,385 Austrian adults, we explored the occurrence of false positives and false negatives with detailed, probing questions. Removing…
Koita, Ousmane A; Doumbo, Ogobara K; Ouattara, Amed; Tall, Lalla K; Konaré, Aoua; Diakité, Mahamadou; Diallo, Mouctar; Sagara, Issaka; Masinde, Godfred L; Doumbo, Safiatou N; Dolo, Amagana; Tounkara, Anatole; Traoré, Issa; Krogstad, Donald J
2012-02-01
We identified 480 persons with positive thick smears for asexual Plasmodium falciparum parasites, of whom 454 had positive rapid diagnostic tests (RDTs) for the histidine-rich protein 2 (HRP2) product of the hrp2 gene and 26 had negative tests. Polymerase chain reaction (PCR) amplification for the histidine-rich repeat region of that gene was negative in one-half (10/22) of false-negative specimens available, consistent with spontaneous deletion. False-negative RDTs were found only in persons with asymptomatic infections, and multiplicities of infection (MOIs) were lower in persons with false-negative RDTs (both P < 0.001). These results show that parasites that fail to produce HRP2 can cause patent bloodstream infections and false-negative RDT results. The importance of these observations is likely to increase as malaria control improves, because lower MOIs are associated with false-negative RDTs and false-negative RDTs are more frequent in persons with asymptomatic infections. These findings suggest that the use of HRP2-based RDTs should be reconsidered.
False negative rates in Drosophila cell-based RNAi screens: a case study
2011-01-01
Background High-throughput screening using RNAi is a powerful gene discovery method but is often complicated by false positive and false negative results. Whereas false positive results associated with RNAi reagents has been a matter of extensive study, the issue of false negatives has received less attention. Results We performed a meta-analysis of several genome-wide, cell-based Drosophila RNAi screens, together with a more focused RNAi screen, and conclude that the rate of false negative results is at least 8%. Further, we demonstrate how knowledge of the cell transcriptome can be used to resolve ambiguous results and how the number of false negative results can be reduced by using multiple, independently-tested RNAi reagents per gene. Conclusions RNAi reagents that target the same gene do not always yield consistent results due to false positives and weak or ineffective reagents. False positive results can be partially minimized by filtering with transcriptome data. RNAi libraries with multiple reagents per gene also reduce false positive and false negative outcomes when inconsistent results are disambiguated carefully. PMID:21251254
Rübenthaler, J; Paprottka, K; Marcon, J; Hameister, E; Hoffmann, K; Joiko, N; Reiser, M; Clevert, D A
2016-01-01
To compare the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) in the evaluation of unclear renal lesions to the histopathological outcome. A total of 36 patients with a single unclear solid renal lesion with initial imaging studies between 2005 and 2015 were included. CEUS and MRI were used for determining malignancy or benignancy and initial findings were correlated with the histopathological outcome. Out of the 36 renal masses a total of 28 lesions were malignant (77.8%) and 8 were found to be benign (22.2%). Diagnostic accuracy was testes by using the histopathological diagnosis as the gold standard. CEUS showed a sensitivity of 96.4%, a specificity of 100.0%, a positive predictive value (PPV) of 100.0% and a negative predictive value (NPV) of 88,9%. MRI showed a sensitivity of 96.4%, a specificity of 75.0%, a PPV of 93.1% and a NPV of 85.7%. Out of the 28 malignant lesions a total of 18 clear cell renal carcinomas, 6 papillary renal cell carcinomas and 4 other malignant lesions, e.g. metastases, were diagnosed. Out of the 8 benign lesions a total 3 angiomyolipomas, 2 oncocytomas, 1 benign renal cyst and 2 other benign lesions, e.g. renal adenomas were diagnosed. Using CEUS, 1 lesion was falsely identified as benign. Using MRI, 2 lesions were falsely identified as benign and 1 lesion was falsely identified as malignant. CEUS is an useful method which can be additionally used to clinically differentiate between malignant and benign renal lesions. CEUS shows a comparable sensitivity, specificity, PPV and NPV to MRI. In daily clinical routine, patients with contraindications for other imaging modalities can particularly benefit using this method.
Thyroid Nodule Size at Ultrasound as a Predictor of Malignancy and Final Pathologic Size.
Cavallo, Allison; Johnson, Daniel N; White, Michael G; Siddiqui, Saaduddin; Antic, Tatjana; Mathew, Melvy; Grogan, Raymon H; Angelos, Peter; Kaplan, Edwin L; Cipriani, Nicole A
2017-05-01
Thyroid-related mortality has remained constant despite the increasing incidence of thyroid carcinoma. Most thyroid nodules are benign; therefore, ultrasound and fine needle aspiration (FNA) are integral in cancer screening. We hypothesize that increased nodule size at ultrasound does not predict malignancy and correlation between nodule size at ultrasound and pathologic exam is good. Resected thyroids with preoperative ultrasounds were identified. Nodule size at ultrasound, FNA diagnosis by Bethesda category, size at pathologic examination, and final histologic diagnosis were recorded. Nodule characteristics at ultrasound and FNA diagnoses were correlated with gross characteristics and histologic diagnoses. Nodules for which correlation could not be established were excluded. Of 1003 nodules from 659 patients, 26% were malignant. Nodules <2 cm had the highest malignancy rate (∼30%). Risk was similar (∼20%) for nodules ≥2 cm. Of the 548 subject to FNA, 38% were malignant. Decreasing malignancy rates were observed with increasing size (57% for nodules <1 cm to 20% for nodules >6 cm). At ultrasound size cutoffs of 2, 3, 4, and 5 cm, smaller nodules had higher malignancy rates than larger nodules. Of the 455 not subject to FNA, 11% were malignant. Ultrasound size alone is a poor predictor of malignancy, but a relatively good predictor of final pathologic size (R 2 = 0.748), with less correlation at larger sizes. In nodules subject to FNA, false negative diagnoses were highest (6-8%) in nodules 3-6 cm, mostly due to encapsulated follicular variant of papillary carcinoma. Thyroid nodule size is inversely related to malignancy risk, as larger nodules have lower malignancy rates. However, the relationship of size to malignancy varies by FNA status. All nodules (regardless of FNA status) demonstrate a risk trough at ≥2 cm. Nodules subject to FNA show step-wise decline in malignancy rates by size, demonstrating that size alone should not be considered as an independent risk factor. Size at ultrasound shows relatively good correlation with final pathologic size. False negative rates are low in this series. Lesions with the appropriate constellation of clinical and radiographic findings should undergo FNA regardless of size. Both size and FNA diagnosis should influence the clinical decision-making process.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Filkins, K.; Russo, J.F.
Advances in the field of prenatal diagnosis have been rapid during the past decade. Moreover, liberal use of birth control methods and restriction of family size have placed greater emphasis on optimum outcome of each pregnancy. There are many prenatal diagnostic techniques of proven value; the risks, including false negatives and false positives, are known. With the rapid proliferation of new and experimental techniques, many disorders are potential diagnosable or even treatable; however, risk factors are unknown and issues relating to quality control have not been resolved. These problems are readily appreciated in the dramatic new techniques involving recombinant DNA,more » chorion villus sampling, and fetal surgery. Unfortunately, clinicians may not appreciate the difficulties that may also be encountered in the more mundane prenatal diagnostic tests such as ultrasonography or enzymatic testing. The aim of this volume is to clarify and rationalize certain aspects of diagnosis, genetic counseling, and intervention. New and experimental techniques are presented in the light of current knowledge.« less
Definitive diagnosis of breast implant rupture using magnetic resonance imaging.
Ahn, C Y; Shaw, W W; Narayanan, K; Gorczyca, D P; Sinha, S; Debruhl, N D; Bassett, L W
1993-09-01
Breast implant rupture is an important complication of augmented and reconstructed breasts. Although several techniques such as mammography, xeromammography, ultrasound, thermography, and computed tomographic (CT) scanning have been proven to be useful to detect implant rupture, they have several disadvantages and lack specificity. In the current study, we have established magnetic resonance imaging (MRI) as a definitive, reliable, and reproducible technique to diagnose both intracapsular and extracapsular ruptures. The study was conducted in 100 symptomatic patients. Our imaging parameters were able to identify ruptures in implants with silicone shells. All the ruptures showed the presence of wavy lines, free-floating silicone shell within the gel ("free-floating loose-thread sign" or "linguine sign"). We had a 3.75 percent incidence of false-positive and false-negative results. The sensitivity for detection of silicone implant rupture was 76 percent, with a specificity of 97 percent. In addition, we also were able to identify the artifacts that may interfere with the definitive diagnosis of implant rupture.
More than just T₄: diagnostic testing for hyperthyroidism in cats.
Peterson, Mark E
2013-09-01
In older cats presenting with clinical features of hyperthyroidism, confirmation of a diagnosis of thyroid disease is usually straightforward. However, the potential for false-negative and false-positive results exists with all thyroid function tests (especially in the context of routine screening of asymptomatic cats) and leads to clinical dilemmas. For example, a high serum T₄ value may be found in a cat that lacks clinical signs of hyperthyroidism, or hyperthyroidism may be suspected in a cat with normal total T₄ concentrations. To avoid unnecessary treatment and potentially adverse effects in a euthyroid cat, thyroid function tests must always be interpreted in the light of the cat's history, clinical signs, physical examination findings and other laboratory findings. In this article the author reviews the use of commonly recommended thyroid function tests, focusing on clinical scenarios that present diagnostic difficulties. In doing so, he draws on the veterinary and comparative literature, his own clinical experience, and data, unpublished to date, obtained from a series of 100 hyperthyroid cats consecutively diagnosed at his clinic.
Diagnosis of metastatic melanoma by fine-needle biopsy: analysis of 2,204 cases.
Murali, Rajmohan; Doubrovsky, Anna; Watson, Geoffrey F; McKenzie, Paul R; Lee, C Soon; McLeod, Duncan J; Uren, Roger F; Stretch, Jonathan R; Saw, Robyn P M; Thompson, John F; Scolyer, Richard A
2007-03-01
Fine-needle biopsy (FNB) has been reported as a rapid, minimally invasive technique for the diagnosis of metastatic melanoma. The diagnostic accuracy of FNB was assessed in a consecutive series of 2,204 FNBs of clinically suspicious lesions from patients with previous primary melanomas treated at the Sydney Melanoma Unit, Sydney, Australia, between January 1992 and December 2002. The sensitivity and specificity of FNB were 96.3% and 98.9%, respectively. There were 5 false-positive cases (0.6%), which were verified as metastatic adenocarcinoma (3 cases) or reactive processes (organizing hematoma and chronic osteomyelitis, 1 each). False-negative diagnoses (6.7% of cases) were associated with a variety of clinicopathologic factors, including difficult-to-access anatomic sites (eg, high axilla or deep inguinal), small lesions, and lesional characteristics such asfibrosis, necrosis, or cystic change. FNB is a highly accurate, rapid, and cost-effective procedure for the diagnosis of metastatic melanoma and should be considered as the initial diagnostic procedure of choice in patients with melanoma with clinically suspected metastases.
ERIC Educational Resources Information Center
Greyson, Bruce
2005-01-01
Some persons who claim to have had near-death experiences (NDEs) fail research criteria for having had NDEs ("false positives"); others who deny having had NDEs do meet research criteria for having had NDEs ("false negatives"). The author evaluated false positive claims and false negative denials in an organization that promotes near-death…
Automatic detection of mycobacterium tuberculosis using artificial intelligence
Xiong, Yan; Ba, Xiaojun; Hou, Ao; Zhang, Kaiwen; Chen, Longsen
2018-01-01
Background Tuberculosis (TB) is a global issue that seriously endangers public health. Pathology is one of the most important means for diagnosing TB in clinical practice. To confirm TB as the diagnosis, finding specially stained TB bacilli under a microscope is critical. Because of the very small size and number of bacilli, it is a time-consuming and strenuous work even for experienced pathologists, and this strenuosity often leads to low detection rate and false diagnoses. We investigated the clinical efficacy of an artificial intelligence (AI)-assisted detection method for acid-fast stained TB bacillus. Methods We built a convolutional neural networks (CNN) model, named tuberculosis AI (TB-AI), specifically to recognize TB bacillus. The training set contains 45 samples, including 30 positive cases and 15 negative cases, where bacilli are labeled by human pathologists. Upon training the neural network model, 201 samples (108 positive cases and 93 negative cases) were collected as test set and used to examine TB-AI. We compared the diagnosis of TB-AI to the ground truth result provided by human pathologists, analyzed inconsistencies between AI and human, and adjusted the protocol accordingly. Trained TB-AI were run on the test data twice. Results Examined against the double confirmed diagnosis by pathologists both via microscopes and digital slides, TB-AI achieved 97.94% sensitivity and 83.65% specificity. Conclusions TB-AI can be a promising support system to detect stained TB bacilli and help make clinical decisions. It holds the potential to relieve the heavy workload of pathologists and decrease chances of missed diagnosis. Samples labeled as positive by TB-AI must be confirmed by pathologists, and those labeled as negative should be reviewed to make sure that the digital slides are qualified. PMID:29707349
Automatic detection of mycobacterium tuberculosis using artificial intelligence.
Xiong, Yan; Ba, Xiaojun; Hou, Ao; Zhang, Kaiwen; Chen, Longsen; Li, Ting
2018-03-01
Tuberculosis (TB) is a global issue that seriously endangers public health. Pathology is one of the most important means for diagnosing TB in clinical practice. To confirm TB as the diagnosis, finding specially stained TB bacilli under a microscope is critical. Because of the very small size and number of bacilli, it is a time-consuming and strenuous work even for experienced pathologists, and this strenuosity often leads to low detection rate and false diagnoses. We investigated the clinical efficacy of an artificial intelligence (AI)-assisted detection method for acid-fast stained TB bacillus. We built a convolutional neural networks (CNN) model, named tuberculosis AI (TB-AI), specifically to recognize TB bacillus. The training set contains 45 samples, including 30 positive cases and 15 negative cases, where bacilli are labeled by human pathologists. Upon training the neural network model, 201 samples (108 positive cases and 93 negative cases) were collected as test set and used to examine TB-AI. We compared the diagnosis of TB-AI to the ground truth result provided by human pathologists, analyzed inconsistencies between AI and human, and adjusted the protocol accordingly. Trained TB-AI were run on the test data twice. Examined against the double confirmed diagnosis by pathologists both via microscopes and digital slides, TB-AI achieved 97.94% sensitivity and 83.65% specificity. TB-AI can be a promising support system to detect stained TB bacilli and help make clinical decisions. It holds the potential to relieve the heavy workload of pathologists and decrease chances of missed diagnosis. Samples labeled as positive by TB-AI must be confirmed by pathologists, and those labeled as negative should be reviewed to make sure that the digital slides are qualified.
Diagnosis of subclinical mastitis in Santa Inês and Morada Nova sheep in southeastern Brazil.
Zafalon, Luiz Francisco; Santana, Raul Costa Mascarenhas; Pilon, Lucas Eduardo; Júnior, Guilherme Aparecido Fim
2016-06-01
The objective of this study was to evaluate different screening limits for the California mastitis test (CMT) and the somatic cell count (SCC) in previous diagnoses of subclinical mastitis in Santa Inês and Morada Nova ewes, which were reared under the same management conditions. Additionally, cutoff points were defined for SCC in accordance with the sensitivity and specificity of the test. A total of 907 mammary halves were subjected to CMT and SCC. The disease was confirmed by means of microbiological identification. Coagulase-negative staphylococci (CNS) were the microorganisms with highest occurrence. The CMT score of 1+ provided adequate sensitivity and specificity at all periods of lactation investigated. This score showed good agreement with SCC, >400,000 cells mL(-1). Higher cell counts favored higher diagnostic specificity. They can be used when producers have financial difficulties relating to treatment or culling of sheep with subclinical mastitis. However, producers should be warned about the risk of false-negative results in the flock.
Nicolau, A E; Merlan, V; Dinescu, G; Crăciun, M; Kitkani, A; Beuran, M
2012-01-01
Blunt hollow viscus perforations (HVP) due to abdominal contusions (AC), although rare, are difficult to diagnose early and are associated with a high mortality. Our paper analyses retrospectively data from patients operated for HVP between January 2005 and January 2009, the efficiency of different diagnostic tools, mortality and prognostic factors for death. There were 62 patients operated for HVP, 14 of which had isolated abdominal contusion and 48 were poly trauma patients. There were 9 women and 53 men, the mean age was 41.5 years (SD: +17,9), the mean ISS was 32.94 (SD: +15,94), 23 patients had associated solid viscus injuries (SVI). Clinical examination was irelevant for 16 of the 62 patients, abdominal Xray was false negative for 30 out of 35 patients and abdominal ultrasound was false negative for 16 out of 60 patients. Abdominal CT was initially false negative for 7 out of 38 patients: for 4 of them the abdominal CT was repeated and was positive for HVP, for 3 patients a diagnostic laparoscopy was performed. Direct signs for HVP on abdominal CT were present for 3 out of 38 patients. Diagnostic laparoscopy was performed for 7 patients with suspicion for HVP, and was positive for 6 of them and false negative for a patient with a duodenal perforation. Single organ perforations were present in 55 cases, multi organ perforations were present in 7 cases. There were 15 deaths (15.2%), most of them caused by haemodynamic instability (3 out of 6 patients) and associated lesions: SOL for 9 out of 23 cases, pelvic fracture (PF) for 6 out of 14 patients, craniocerebral trauma (CCT) for 12 out of 33 patients.Multivariate analysis showed that the prognostic factors for death were ISS value (p = 0,023) and associated CCT (odds ratio = 4,95; p = 0,017). The following factors were not confirmed as prognostic factors for death: age, haemodynamic instability, associated SVI, thoracic trauma (TT), pelvic fractures (PF), limbs fractures (LF) and admission-operation interval under 6 hours. Hollow viscus perforations due to abdominal contusions have a high mortality, early diagnosis is difficult, repeated abdominal CT and the selective use of diagnostic laparoscopy for haemodynamic stable patients with ambiguous clinical examination and diagnostic imaging are salutary. Prognostic factors for death were the ISS value and associated craniocerebral trauma.
ERIC Educational Resources Information Center
Nguyen, Cathina T.; Fairclough, Diane L.; Noll, Robert B.
2016-01-01
Problem-solving skills training is an intervention designed to teach coping skills that has shown to decrease negative affectivity (depressive symptoms, negative mood, and post-traumatic stress symptoms) in mothers of children with cancer. The objective of this study was to see whether mothers of children recently diagnosed with autism spectrum…
[Diagnostic tools for canine parvovirus infection].
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.
Geiger, A M; Foxman, B; Sobel, J D
1995-01-01
INTRODUCTION--Although as many as 5% of all women complain of chronic vulvovaginitis, little is known about these women. They may often be misdiagnosed and the role of vaginal yeast culture in diagnosing vulvovaginal candidiasis (VVC) among them has not been clearly defined. METHODS--To address these deficiencies, we tabulated initial diagnoses among new patients and conducted a medical record-based, unmatched case-control study among women reporting a history of chronic vulvovaginitis (four or more episodes in the past year) at a vulvovaginitis specialty clinic. Clinical presentation and medical history were compared for women who had a positive vaginal yeast culture for either Candida albicans or C glabrata, or who had a negative culture. RESULTS--One-third of the women had no apparent vulvovaginal disease at their initial visit. All women reported similar symptoms, except for an increased prevalence of painful sexual intercourse in women with C albicans (chi 2 p = 0.014 versus women with C glabrata and p < 0.001 versus women with no candida). Women with C glabrata were more likely to be non-white (chi 2 p = 0.071 compared with women with C albicans) and to report an underlying medical condition (chi 2 p < or = 0.001 versus both women with C albicans and women with no candida). Physical examination was normal only in women with no candida. C albicans cases were more likely to have positive potassium hydroxide microscopy (chi 2 p = 0.016) and a pH < or = 4.5 (chi 2 p = 0.011) than were C glabrata cases. CONCLUSIONS--These results suggest that reliance on symptoms and signs alone will result in significant misdiagnosis of chronic vulvovaginitis. Among women with VVC, subtle differences in clinical presentation do not reliably distinguish women with C albicans from those with C glabrata. Our study also indicates that vaginal yeast cultures, while not necessary for every patient, are valuable in confirming negative diagnoses, detecting microscopy false-negatives, and identifying non-C albicans isolates. Images PMID:7490047
Plate, Andreas; Stadler, Laura; Sutter, Reto; Anagnostopoulos, Alexia; Frustaci, Dario; Zbinden, Reinhard; Fucentese, Sandro F; Zinkernagel, Annelies S; Zingg, Patrick O; Achermann, Yvonne
2018-02-26
The antimicrobial peptide α-defensin has recently been introduced as potential "single" biomarker with a high sensitivity and specificity for the preoperative diagnosis of periprosthetic joint infections (PJIs). However, most studies assessed the benefits of the test with exclusion of patients with rheumatic diseases. We aimed to evaluate the α-defensin test in a cohort study without exclusion of cases with inflammatory diseases. Between June 2016 and June 2017, we prospectively included cases with a suspected PJI and an available lateral flow test α-defensin (Synovasure®) in synovial fluid. We compared the test result to the diagnostic criteria for PJIs published by an International Consensus Group in 2013. We included 109 cases (49 hips, 60 knees) in which preoperative α-defensin tests had been performed. Thereof, 20 PJIs (16 hips, 4 knees) were diagnosed. Preoperative α-defensin tests were positive in 25 cases (22.9%) with a test sensitivity and specificity of 90% and 92.1% (95% confidence interval [CI], 68.3 - 98.8% and 84.5 - 96.8%, respectively), and a high negative predictive value of 97.6% (95% CI, 91.7 - 99.4%). We interpreted seven α-defensin tests as false positive, mainly in cases with inflammatory rheumatic diseases, including crystal deposition diseases. A negative synovial α-defensin test can reliably rule out a PJI. However, the test can be false positive in conjunction with an underlying non-infectious inflammatory disease. We therefore propose to use the α-defensin test only in addition to MSIS criteria and assessment for crystals in synovial aspirates. Copyright © 2018. Published by Elsevier Ltd.
Cardona, Diana M; Detweiler, Claire J; Shealy, Michael J; Sung, Anthony D; Wild, Daniel M; Poleski, Martin H; Balmadrid, Bryan L; Cirrincione, Constance T; Howell, David N; Sullivan, Keith M
2018-04-26
- Graft-versus-host disease of the gastrointestinal tract is a common complication of hematopoietic stem cell transplant associated with significant morbidity and mortality. Accurate diagnosis can be difficult and is a truly clinicopathologic endeavor. - To assess the diagnostic sensitivity of gastrointestinal graft-versus-host disease using the 2015 National Institutes of Health (NIH) histology consensus guidelines and to analyze histologic findings that support the guidelines. - Patients with allogeneic hematopoietic stem cell transplants were identified via a retrospective search of our electronic medical record from January 1, 2005, to January 1, 2011. Endoscopies with available histology were reviewed by 2 pathologists using the 2015 NIH guidelines. The clinical diagnosis was used as the gold standard. A nontransplant set of endoscopic biopsies was used as a control. - Of the 250 total endoscopies, 217 (87%) had a clinical diagnosis of gastrointestinal graft-versus-host disease. Use of the NIH consensus guidelines showed a sensitivity of 86% and a specificity of 65%. Thirty-seven of 58 (64%) cases with an initial false-negative histopathologic diagnosis were diagnosed as graft-versus-host disease on our review. - Use of the NIH histology consensus guidelines results in a high sensitivity and specificity, thereby decreasing false-negatives. Additionally, use of the NIH guidelines aids in creating uniformity and diagnostic clarity. Correlation with clinical and laboratory findings is critical in evaluating the differential diagnosis and to avoid false-positives. As expected, increased apoptosis with decreased inflammation was associated with a pathologic diagnosis of graft-versus-host disease and supports the NIH guidelines.
Cheurfa, N; Giard, S
2015-01-01
Despite the standard management of non-palpable breast cancer (needle core biopsy diagnostic, accurate preoperative localization), there are differences in some cases between the malignant histo-pathological finding in diagnostic biopsy results and negative histo-pathological finding after surgical excision. The aim of this study is to evaluate this incidence and classifying them under three category: failure of surgical excision after preoperative identification; removal of the tumor was already completed by percutaneous biopsy; percutaneous biopsy true false positive. We conducted a study based on prospective database, all patients included in this study had partial mastectomy for ductal carcinoma in-situ or invasive cancer which was diagnosed by needle core biopsy and normal/benign after surgery. Regarding the partial mastectomy, 1863 was performed in the last three years in our center. Thirty-seven patients (2%) correspond our study criteria. After discussion of cases in our multidisciplinary reunion, 6 patients (16%) were considered as failure of surgical excision, 26 patients (70%) as true removal of the whole lesion in the core, and 5 patients (13%) as true false-positive cores. This is the first study witch investigate all factors that influence the results of negative final histo-pathological finding of surgical excision of the tumor after malignant diagnostic needle core biopsy. This rare situation need a multidisciplinary meeting to analyse all the steps of management and to determine causes of those false results and try to find adequate management to solve this problem. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Tham, Jill M.; Lee, Szu Hee; Tan, Theresa M. C.; Ting, Robert C. Y.; Kara, Ursula A. K.
1999-01-01
A rapid procedure for the diagnosis of malaria infections directly from dried blood spots by PCR amplification was evaluated with samples from 52 patients. Plasmodium infections were identified with a genus-specific primer set, and species differentiation between Plasmodium falciparum and Plasmodium vivax was analyzed by multiplex PCR. The PCR test with any of the three primer sets was able to detect as few as four parasites per microliter by gel electrophoresis or by nonisotopic paper hybridization chromatography. The diagnoses obtained by PCR correlated closely with those obtained by Giemsa staining except for two samples observed to have mixed P. falciparum-P. vivax infections. These were initially missed by microscopic analysis. In comparison with antigen-capture assays for P. falciparum, the PCR assays were able to detect three infections that were missed by the ParaSight-F test. The PCR test was negative for nine ParaSight-F-positive samples and one ICT Malaria Pf-positive sample, and these were confirmed to be false-positive results. The PCR thus gave no false-negative or false-positive results. Patients undergoing antimalarial therapy were also monitored by the PCR assay. Four of seven patients who were PCR positive for P. vivax at the time of discharge were later readmitted to the hospital with a recurrence of P. vivax infection. We would like to propose that PCR is a sensitive and easy method that can serve as a useful addition to microscopy for the diagnosis and the clinical monitoring of treatment of malaria. PMID:10203469
Chindima, Nanjela; Nkhoma, Panji; Sinkala, Musalula; Zulu, Mildred; Kafita, Doris; Simakando, Marah; Mwaba, Florence; Mantina, Hamakwa; Mutale, Mubanga
2018-01-01
Sickle cell disease is a group of hemoglobin (Hb) disorders resulting from the inheritance of the sickle β-globin gene. It is the most common pathological Hb mutation worldwide with 75% being born in Sub-Saharan Africa. This study aims to determine if dried blood spots (DBSs) can be used for diagnosis of sickle cell in newborns. In Zambia, there is no neonatal screening program for sickle cell anemia (SCA), yet it has been proved that early diagnosis by newborn screening (NBS) using DBSs and access to comprehensive care results in survival to adulthood of over 96% of sickle cell patients. A cross-sectional study was carried out at the University Teaching Hospital to determine whether DBSs can be used to diagnose sickle cell using Hb electrophoresis. Results from DBSs stored for 2 weeks were then compared to those obtained using freshly collected whole blood. To evaluate performance characteristics, the following values were used: true positive, false positive, true negative, and false negative. Ninety-seven participants were included in this study. DBSs had a sensitivity of 100%, a specificity of 94.7%, positive predictive value of 96.7%, negative predictive value of 100%, overall efficiency of 97.9%, and a Kappa r 2 , P < 0.0001 in comparison to fresh whole blood which we used as the gold standard. The use of DBSs can be recommended for NBS of SCA in Zambia due to its high sensitivity, specificity, and stability of hemoglobin.
Malaria rapid diagnostic test evaluation at private retail pharmacies in Kumasi, Ghana.
Audu, Rauf; Anto, Berko Panyin; Koffuor, George Asumeng; Abruquah, Akua Afriyie; Buabeng, Kwame Ohene
2016-01-01
Malaria rapid diagnostic test (MRDT) provides a good alternative to malaria microscopy diagnosis, particularly in resource-constrained settings. This study therefore evaluated MRDT in private retail pharmacies (PRPs) as a critical step in community case malaria management. In a prospective, cross-over, validation survey at six PRPs in the Ashanti Region of Ghana, 1200 patients presenting with fever in the preceding 48 h were sampled. Fingerstick blood samples were collected for preparation of thick and thin blood films for malaria microscopy. Categorized patients (600 each) went through the processes of MRDT or presumptive diagnosis (PD) of malaria. The malaria disease prevalence of the study area was established. Selectivity (Se), specificity (Sp), positive predictive value (PPV) along with false discovery rate (FDR), and negative predictive value (NPV) along with the false omission rate (FOR), and diagnostic odds ratio (DOR) of MRDT were then calculated. While 43.0% tested positive using the MRDT, 57.0% tested negative. However, 62.0% MRDT-negative patients in addition to all the MRDT positives were given artemether-lumefantrine. Of those diagnosed by PD, 98.2% were prescribed with an antimalarial (microscopy however confirmed only 70.3% as positive). Se and Sp of the MRDT were 90.68 ± 11.18% and 98.68 ± 1.19%, respectively. Malaria prevalence was estimated to be 43.3%. PPV was 98.0%, FDR was 2.0%, NPV was 98.0%, FOR was 2.0%, and DOR was 2366.43. Results highlighted good performance of MRDTs at PRPs which could inform decision toward its implementation.
Linguistic Determinants of the Difficulty of True-False Test Items
ERIC Educational Resources Information Center
Peterson, Candida C.; Peterson, James L.
1976-01-01
Adults read a prose passage and responded to passages based on it which were either true or false and were phrased either affirmatively or negatively. True negatives yielded most errors, followed in order by false negatives, true affirmatives, and false affirmatives. (Author/RC)
The impact of meal consumption on emotion among individuals with eating disorders.
Anderson, Lisa M; Crow, Scott J; Peterson, Carol B
2014-01-01
This pilot study sought to determine how meal consumption impacts affective states for treatment-seeking individuals with eating disorders (ED). Participants with heterogeneous ED diagnoses completed the State-Trait Anxiety Inventory, Positive and Negative Affect Schedule, and Profile of Mood States measures before and immediately after meal consumption. Meal consumption was associated with significant decreases in negative affect and total mood disturbance for individuals with binge eating disorder (BED). Decreases in negative affect across meal time for individuals with BED were significantly different from increases in negative affect for participants with anorexia nervosa (AN) and bulimia nervosa (BN). Findings indicate that individuals with BED have significantly different affective responses to eating non-binge meals than individuals with AN or BN. Data suggest changes in negative affect following meal consumption may be specific to certain ED diagnoses. Results provide preliminary evidence consistent with the idea that emotion states may function as maintenance mechanisms for psychopathology among ED diagnoses. Limitations and future directions pertaining to food-mood relationships for individuals with ED are discussed.
Llata, Eloisa; Braxton, Jim; Asbel, Lenore; Kerani, Roxanne P; Murphy, Ryan; Pugsley, River; Pathela, Preeti; Schumacher, Christina; Tabidze, Irina; Weinstock, Hillard S
2018-02-07
To estimate new HIV diagnosis rates among HIV negative MSM who are repeatedly tested for HIV in sexually transmitted disease (STD) clinics, and assess the impact of demographic and disease-specific characteristics that are associated with higher HIV diagnosis rates. Retrospective analysis using 2010-2013 data from the STD Surveillance Network (SSuN), a sentinel surveillance system comprised of health departments in 12 cities conducting sentinel surveillance in 40 STD clinics. We analyzed data from all MSM repeatedly (≥2 times) tested for HIV, with an initial negative HIV test required for staggered cohort entry. Follow-up time was accrued from the date of the first negative HIV test to the most recent negative test or the first positive HIV test. STD diagnoses during the follow-up period were reviewed. We estimated HIV diagnoses rates (number of HIV diagnoses/total number of person-years at risk) by demographic and clinical characteristics with 95% confidence intervals (CI) using an inverse variance weighted random effects model, adjusting for heterogeneity between SSuN jurisdictions. Overall, 640 HIV diagnoses occurred among 14,824 individuals and 20,951.6 person-years (PY) of observation, for an adjusted incidence of HIV diagnosis of 3.0 per 100 PY (95% CI 2.6, 3.4). Rates varied across race/ethnicity groups with the highest rate among Blacks (4.7/100 PY; 95% CI 4.1-5.3) followed by Hispanics, Whites and persons of other races/ethnicities. MSM having a diagnosis of P&S syphilis on or after the first negative HIV test had a higher new HIV diagnosis rate (7.2/100 PY; 95% CI 5.8-9.0) compared to MSM who did not have a P&S syphilis diagnosis (2.8/100 PY; 95% CI 2.6-3.1). MSM who tested positive for rectal gonorrhea (6.3/100 PY; 95% CI 5.7-6.9) or rectal chlamydia (5.6/100 PY; 95% CI 4.6-6.6) had higher rates of new HIV diagnosis when compared to those with negative test results. MSM attending SSuN STD clinics have high rates of new HIV diagnoses, particularly those with a previous diagnosis of P&S syphilis, rectal chlamydia and/or gonorrhea. STD clinics continue to be important clinical setting for diagnosing HIV among MSM populations.
Anti-retroviral therapy-induced status epilepticus in "pseudo-HIV serodeconversion".
Etgen, Thorleif; Eberl, Bernhard; Freudenberger, Thomas
2010-01-01
Diligence in the interpretation of results is essential as information gained from the psychiatric patient's history might often be restricted. Nonobservance of established guidelines may lead to a wrong diagnosis, induce a false therapy and result in life-threatening situations. Communication errors between hospitals and doctors and uncritical acceptance of prior diagnoses add substantially to this problem. We present a patient with alcohol-related dementia who received anti-retroviral therapy that promoted a non-convulsive status epilepticus. HIV serodeconversion was considered after our laboratory result yielded a HIV-negative status. Critical review of previous diagnostic investigations revealed several errors in the diagnosis of HIV infection leading to a "pseudo-serodeconversion." Finally, anti-retroviral therapy could be discontinued. Copyright © 2010 Elsevier Inc. All rights reserved.
Fàbregas, N; Ewig, S; Torres, A; El-Ebiary, M; Ramirez, J; de La Bellacasa, J P; Bauer, T; Cabello, H
1999-10-01
A study was undertaken to assess the diagnostic value of different clinical criteria and the impact of microbiological testing on the accuracy of clinical diagnosis of suspected ventilator associated pneumonia (VAP). Twenty five deceased mechanically ventilated patients were studied prospectively. Immediately after death, multiple bilateral lung biopsy specimens (16 specimens/patient) were obtained for histological examination and quantitative lung cultures. The presence of both histological pneumonia and positive lung cultures was used as a reference test. The presence of infiltrates on the chest radiograph and two of three clinical criteria (leucocytosis, purulent secretions, fever) had a sensitivity of 69% and a specificity of 75%; the corresponding numbers for the clinical pulmonary infection score (CPIS) were 77% and 42%. Non-invasive as well as invasive sampling techniques had comparable values. The combination of all techniques achieved a sensitivity of 85% and a specificity of 50%, and these values remained virtually unchanged despite the presence of previous treatment with antibiotics. When microbiological results were added to clinical criteria, adequate diagnoses originating from microbiological results which might have corrected false positive and false negative clinical judgements (n = 5) were countered by a similar proportion of inadequate diagnoses (n = 6). Clinical criteria had reasonable diagnostic values. CPIS was not superior to conventional clinical criteria. Non-invasive and invasive sampling techniques had diagnostic values comparable to clinical criteria. An algorithm guiding antibiotic treatment exclusively by microbiological results does not increase the overall diagnostic accuracy and carries the risk of undertreatment.
Working memory affects false memory production for emotional events.
Mirandola, Chiara; Toffalini, Enrico; Ciriello, Alfonso; Cornoldi, Cesare
2017-01-01
Whereas a link between working memory (WM) and memory distortions has been demonstrated, its influence on emotional false memories is unclear. In two experiments, a verbal WM task and a false memory paradigm for negative, positive or neutral events were employed. In Experiment 1, we investigated individual differences in verbal WM and found that the interaction between valence and WM predicted false recognition, with negative and positive material protecting high WM individuals against false remembering; the beneficial effect of negative material disappeared in low WM participants. In Experiment 2, we lowered the WM capacity of half of the participants with a double task request, which led to an overall increase in false memories; furthermore, consistent with Experiment 1, the increase in negative false memories was larger than that of neutral or positive ones. It is concluded that WM plays a critical role in determining false memory production, specifically influencing the processing of negative material.
Rahman, Muhammad Aziz; Spurrier, Nicola; Mahmood, Mohammad Afzal; Rahman, Mahmudur; Choudhury, Sohel Reza; Leeder, Stephen
2013-01-01
Aim/objectives The study aimed to validate the Rose Angina Questionnaire (RAQ) to detect coronary heart disease (CHD) by comparing with cardiologists' diagnoses in Bangladesh. Methods Patients aged 40–75 years attending to two cardiac hospitals were diagnosed as either CHD positive or CHD negative by cardiologists. The RAQ was used to reclassify them into CHD positive [RAQ] and CHD negative [RAQ]. Findings There were 302 CHD positive [cardiologists] and 302 CHD negative [cardiologists] individuals. The RAQ reclassified 194 individuals as CHD positive [RAQ] and 409 individuals as CHD negative [RAQ]. Therefore, the RAQ had 53% sensitivity and 89% specificity. There was no difference in sensitivity and specificity during subgroup analyzes by age and gender; the sensitivity was higher among people from lower socio-economic status. Conclusion The RAQ, having moderate sensitivity but high specificity to detect CHD, can be used to screen individuals at risk of CHD in large-scale epidemiological surveys. PMID:23438610
Dybek, Inga; Bischof, Gallus; Grothues, Janina; Reinhardt, Susa; Meyer, Christian; Hapke, Ulfert; John, Ulrich; Broocks, Andreas; Hohagen, Fritz; Rumpf, Hans-Jürgen
2006-05-01
Our goal was to analyze the retest reliability and validity of the Alcohol Use Disorders Identification Test (AUDIT) in a primary-care setting and recommend a cut-off value for the different alcohol-related diagnoses. Participants recruited from general practices (GPs) in two northern German cities received the AUDIT, which was embedded in a health-risk questionnaire. In total, 10,803 screenings were conducted. The retest reliability was tested on a subsample of 99 patients, with an intertest interval of 30 days. Sensitivity and specificity at a number of different cut-off values were estimated for the sample of alcohol consumers (n=8237). For this study, 1109 screen-positive patients received a diagnostic interview. Individuals who scored less than five points in the AUDIT and also tested negative in a second alcohol-related screen were defined as "negative" (n=6003). This definition was supported by diagnostic interviews of 99 screen-negative patients from which no false negatives could be detected. As the gold standard for detection of an alcohol-use disorder (AUD), we used the Munich-Composite International Diagnostic Interview (MCIDI), which is based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria. On the item level, the reliability, measured by the intraclass correlation coefficient (ICC), ranged between .39 (Item 9) and .98 (Item 10). For the total score, the ICC was .95. For cut-off values of eight points and five points, 87.5% and 88.9%, respectively, of the AUDIT-positives, and 98.9% and 95.1%, respectively, of the AUDIT-negatives were identically identified at retest, with kappa = .86 and kappa = .81. At the cut-off value of five points, we determined good combinations of sensitivity and specificity for the following diagnoses: alcohol dependence (sensitivity and specificity of .97 and .88, respectively), AUD (.97 and .92), and AUD and/or at-risk consumption (.97 and .91). Embedded in a health-risk questionnaire in primary-care settings, the AUDIT is a reliable and valid screening instrument to identify at-risk drinkers and patients with an AUD. Our findings strongly suggest a lowering of the recommended cut-off value of eight points.
Dilute Russel Viper Venom Time analysis in a Haematology Laboratory: An audit.
Kruger, W; Meyer, P W A; Nel, J G
2018-04-17
To determine whether the current set of evaluation criteria used for dilute Russel Viper Venom Time (dRVVT) investigations in the routine laboratory meet expectation and identify possible shortcomings. All dRVVT assays requested from January 2015 to December 2015 were appraised in this cross-sectional study. The raw data panels were compared with the new reference interval, established in 2016, to determine the sequence of assays that should have been performed. The interpretive comments were audited, and false-negative reports identified. Interpretive comments according to three interpretation guidelines were compared. The reagent cost per assay was determined, and reagent cost wastage, due to redundant tests, was calculated. Only ~9% of dRVVT results authorized during 2015 had an interpretive comment included in the report. ~15% of these results were false-negative interpretations. There is a significant statistical difference in interpretive comments between the three interpretation methods. Redundant mixing tests resulted in R 7477.91 (~11%) reagent cost wastage in 2015. We managed to demonstrate very evident deficiencies in our own practice and managed to establish a standardized workflow that will potentially render our service more efficient and cost effective, aiding clinicians in making improved treatment decisions and diagnoses. Furthermore, it is essential that standard operating procedures be kept up to date and executed by all staff in the laboratory. © 2018 John Wiley & Sons Ltd.
Storbeck, Justin
2013-01-01
I investigated whether negative affective states enhance encoding of and memory for item-specific information reducing false memories. Positive, negative, and neutral moods were induced, and participants then completed a Deese-Roediger-McDermott (DRM) false-memory task. List items were presented in unique spatial locations or unique fonts to serve as measures for item-specific encoding. The negative mood conditions had more accurate memories for item-specific information, and they also had fewer false memories. The final experiment used a manipulation that drew attention to distinctive information, which aided learning for DRM words, but also promoted item-specific encoding. For the condition that promoted item-specific encoding, false memories were reduced for positive and neutral mood conditions to a rate similar to that of the negative mood condition. These experiments demonstrated that negative affective cues promote item-specific processing reducing false memories. People in positive and negative moods encode events differently creating different memories for the same event.
Very Early Processing Skills and Language Acquisition in Autism Spectrum Disorder
ERIC Educational Resources Information Center
Kushner, Nicole Blake
2017-01-01
With the increasing prevalence of autism diagnoses, large percentage of diagnosed individuals with comorbid language difficulties, and negative effects of these difficulties on language development and overall functioning, research on language acquisition in children diagnosed with autism spectrum disorder is essential. The current study used data…
Early diagnosis from newborn screening maximises survival in severe cystic fibrosis.
Tridello, Gloria; Castellani, Carlo; Meneghelli, Ilaria; Tamanini, Anna; Assael, Baroukh M
2018-04-01
Newborn screening (NBS) for cystic fibrosis (CF) has been gradually established in several countries, but scant data are available on its long-term effects on survival. Our objective was to evaluate the long-term effects of CF NBS on survival. 586 patients, diagnosed and followed between 1971 and 2014 at the Verona CF Centre were analysed. Eligibility was confirmed in 342 cases diagnosed by NBS, 101 with meconium ileus and 143 through symptoms (44 out of 143 were NBS false negatives). The primary end-point was the 30-year overall survival in patients diagnosed by NBS. Patients were grouped according to the number of hospitalisations for respiratory or nutritional symptoms in the first 3 years of life: 0 (mild), 1-2 (moderate) and ≥3 (severe). Survival in NBS and symptoms groups was compared. The 30-year survival probability of the NBS group was 80.1% (95% CI 71.4-86.4%); in the symptoms group it was 71.0% (95% CI 62.2-78.2%). The 20-year survival was significantly higher in the NBS versus symptoms group in the severe (85% versus 64%, p=0.007) and moderate (94% versus 86%, p=0.016) groups. An adjusted Cox-model estimation confirmed differences in both the groups. Poor outcome associated with early severe presentation of CF is tempered by NBS.
Rapid Detection of Herpes Viruses for Clinical Applications
NASA Technical Reports Server (NTRS)
Pierson, Duane; Mehta, Satish
2013-01-01
There are eight herpes viruses that infect humans, causing a wide range of diseases resulting in considerable morbidity and associated costs. Varicella zoster virus (VZV) is a human herpes virus that causes chickenpox in children and shingles in adults. Approximately 1,000,000 new cases of shingles occur each year; post-herpetic neuralgia (PHN) follows shingles in 100,000 to 200,000 people annually. PHN is characterized by debilitating, nearly unbearable pain for weeks, months, and even years. The onset of shingles is characterized by pain, followed by the zoster rash, leading to blisters and severe pain. The problem is that in the early stages, shingles can be difficult to diagnose; chickenpox in adults can be equally difficult to diagnose. As a result, both diseases can be misdiagnosed (false positive/negative). A molecular assay has been adapted for use in diagnosing VZV diseases. The polymerase chain reaction (PCR) assay is a non-invasive, rapid, sensitive, and highly specific method for VZV DNA detection. It provides unequivocal results and can effectively end misdiagnoses. This is an approximately two-hour assay that allows unequivocal diagnosis and rapid antiviral drug intervention. It has been demonstrated that rapid intervention can prevent full development of the disease, resulting in reduced likelihood of PHN. The technology was extended to shingles patients and demonstrated that VZV is shed in saliva and blood of all shingles patients. The amount of VZV in saliva parallels the medical outcome.
Wakefield, Jerome C; First, Michael B
2012-02-01
The Diagnostic and Statistical Manual of Mental Disorders (DSM) definition of mental disorder requires that symptoms be caused by a dysfunction in the individual; when dysfunction is absent, symptoms represent normal-range distress or eccentricity and, if diagnosed as a mental disorder, are false positives. We hypothesized that because of psychiatry's lack of direct laboratory tests to distinguish dysfunction from normal-range distress, the context in which symptoms occur (eg, lack of imminent danger in a panic attack) is often essential to determining whether symptoms are caused by a dysfunction. If this is right, then the DSM diagnostic criteria should include many contextual criteria added to symptom syndromes to prevent dysfunction false positives. Despite their potential importance, such contextual criteria have not been previously reviewed. We, thus, systematically reviewed DSM categories to establish the extent of such uses of contextual criteria and created a typology of such uses. Of 111 sampled categories, 68 (61%) used context to prevent dysfunction false positives. Contextual criteria fell into 7 types: (1) exclusion of specific false-positive scenarios; (2) requiring that patients experience preconditions for normal responses (eg, requiring that individuals experience adequate sexual stimulation before being diagnosed with sexual dysfunctions); (3) requiring that symptoms be disproportionate relative to circumstances; (4) for childhood disorders, requiring that symptoms be developmentally inappropriate; (5) requiring that symptoms occur in multiple contexts; (6) requiring a substantial discrepancy between beliefs and reality; and (7) a residual category. Most DSM categories include contextual criteria to eliminate false-positive diagnoses and increase validity of descriptive criteria. Future revisions should systematically evaluate each category's need for contextual criteria. Copyright © 2012 Elsevier Inc. All rights reserved.
Honda, Hideo; Shimizu, Yasuo; Nitto, Yukari; Imai, Miho; Ozawa, Takeshi; Iwasa, Mitsuaki; Shiga, Keiko; Hira, Tomoko
2009-08-01
For early detection of autism, it is difficult to maintain an efficient level of sensitivity and specificity based on observational data from a single screening. The Extraction and Refinement (E&R) Strategy utilizes a public children's health surveillance program to produce maximum efficacy in early detection of autism. In the extraction stage, all cases at risk of childhood problems, including developmental abnormality, are identified; in the refinement stage, cases without problems are excluded, leaving only cases with conclusive diagnoses. The city of Yokohama, Japan, conducts a routine child health surveillance program for children at 18 months in which specialized public health nurses administer YACHT-18 (Young Autism and other developmental disorders CHeckup Tool), a screening instrument to identify children at risk for developmental disorders. Children who screen positive undergo further observation, and those without disorders are subsequently excluded. To study the efficacy of early detection procedures for developmental disorders, including autism, 2,814 children born in 1988, examined at 18 months of age, and not already receiving treatment for diseases or disorders were selected. In the extraction stage, 402 (14.3%) children were identified for follow-up. In the refinement stage, 19 (.7%) of these were referred to the Yokohama Rehabilitation Center and diagnosed with developmental disorders. The extraction stage produced four false negatives, bringing total diagnoses of developmental disorders to 23 (.8%) - including 5 with autistic disorder and 9 with pervasive developmental disorder - not otherwise specified (PDDNOS). Sensitivity was 60% for autistic disorder and 82.6% for developmental disorders. Specificity for developmental disorders rose to 100% with the E&R Strategy. Picture cards used in YACHT-18 provided a finer screen that excluded some false positive cases. An extraction and refinement methodology utilizing child health surveillance programs achieve high efficacy for early detection of autism.
NASA Astrophysics Data System (ADS)
Mirniaharikandehei, Seyedehnafiseh; Hollingsworth, Alan B.; Patel, Bhavika; Heidari, Morteza; Liu, Hong; Zheng, Bin
2018-05-01
This study aims to investigate the feasibility of identifying a new quantitative imaging marker based on false-positives generated by a computer-aided detection (CAD) scheme to help predict short-term breast cancer risk. An image dataset including four view mammograms acquired from 1044 women was retrospectively assembled. All mammograms were originally interpreted as negative by radiologists. In the next subsequent mammography screening, 402 women were diagnosed with breast cancer and 642 remained negative. An existing CAD scheme was applied ‘as is’ to process each image. From CAD-generated results, four detection features including the total number of (1) initial detection seeds and (2) the final detected false-positive regions, (3) average and (4) sum of detection scores, were computed from each image. Then, by combining the features computed from two bilateral images of left and right breasts from either craniocaudal or mediolateral oblique view, two logistic regression models were trained and tested using a leave-one-case-out cross-validation method to predict the likelihood of each testing case being positive in the next subsequent screening. The new prediction model yielded the maximum prediction accuracy with an area under a ROC curve of AUC = 0.65 ± 0.017 and the maximum adjusted odds ratio of 4.49 with a 95% confidence interval of (2.95, 6.83). The results also showed an increasing trend in the adjusted odds ratio and risk prediction scores (p < 0.01). Thus, this study demonstrated that CAD-generated false-positives might include valuable information, which needs to be further explored for identifying and/or developing more effective imaging markers for predicting short-term breast cancer risk.
van de Groep, Kirsten; Bos, Martine P; Savelkoul, Paul H M; Rubenjan, Anna; Gazenbeek, Christel; Melchers, Willem J G; van der Poll, Tom; Juffermans, Nicole P; Ong, David S Y; Bonten, Marc J M; Cremer, Olaf L
2018-04-26
Molecular tests may enable early adjustment of antimicrobial therapy and be complementary to blood culture (BC) which has imperfect sensitivity in critically ill patients. We evaluated a novel multiplex real-time PCR assay to diagnose bloodstream pathogens directly in whole blood samples (BSI-PCR). BSI-PCR included 11 species- and four genus-specific PCRs, a molecular Gram-stain PCR, and two antibiotic resistance markers. We collected 5 mL blood from critically ill patients simultaneously with clinically indicated BC. Microbial DNA was isolated using the Polaris method followed by automated DNA extraction. Sensitivity and specificity were calculated using BC as reference. BSI-PCR was evaluated in 347 BC-positive samples (representing up to 50 instances of each pathogen covered by the test) and 200 BC-negative samples. Bacterial species-specific PCR sensitivities ranged from 65 to 100%. Sensitivity was 26% for the Gram-positive PCR, 32% for the Gram-negative PCR, and ranged 0 to 7% for yeast PCRs. Yeast detection was improved to 40% in a smaller set-up. There was no overall association between BSI-PCR sensitivity and time-to-positivity of BC (which was highly variable), yet Ct-values were lower for true-positive versus false-positive PCR results. False-positive results were observed in 84 (4%) of the 2200 species-specific PCRs in 200 culture-negative samples, and ranged from 0 to 6% for generic PCRs. Sensitivity of BSI-PCR was promising for individual bacterial pathogens, but still insufficient for yeasts and generic PCRs. Further development of BSI-PCR will focus on improving sensitivity by increasing input volumes and on subsequent implementation as a bedside test.
Chen, Jin-feng; Liu, Yi-nan; Wu, Nan; Feng, Yuan; Wang, Jia; Lü, Chao; Wang, Yu-zhao; Pei, Yu-quan; Yan, Shi; Zheng, Qing-feng; Zhang, Li-jian; Yang, Yue
2012-04-01
To investigate the diagnostic accuracy of needle puncture biopsy and pathological examination of frozen during operation for pulmonary nodules, and whether this diagnostic method can replace tumor resection examination. Totally 50 patients (28 males and 22 females, average age was 59 years) who had the single nodule after imaging examination without any pathological diagnostic from January to October 2010 were selected in this research work. During open operation or video assisted thoracic surgery, needle (14 G model) was used to puncture biopsy for pathological examination of frozen. All the adverse events during puncture biopsy would be recorded. The resection specimens would be accepted paraffin pathological examination. The relationship between puncture frozen pathological and paraffin pathological examination was analyzed. All tumor sizes were ranged from 1.0 cm × 0.6 cm to 5.6 cm × 9.0 cm. The paraffin pathological examination after operation as the golden standard, there were 7 cases of benign tumor and 43 cases of malignant tumor. The diagnostic sensitivity of puncture biopsy was 90.7%, the specificity was 100%, the positive predictive value was 100% and the negative predictive value was 63.6%. There were 11 cases of benign tumor diagnosed by needle puncture biopsy, among which 4 cases were proved as malignant tumor by paraffin pathology, and the false negative rate was 9.3%. The main risk of puncture biopsy was bleeding after puncture immediately, and the rate was 4.0% (2/50). The puncture biopsy during operation had a high specificity for malignant lung tumor, and there was a certain false negative rate for benign tumor. Puncture biopsy and pathological examination of frozen tissue can replace tumor section biopsy in a way.
Valence and the development of immediate and long-term false memory illusions.
Howe, Mark L; Candel, Ingrid; Otgaar, Henry; Malone, Catherine; Wimmer, Marina C
2010-01-01
Across five experiments we examined the role of valence in children's and adults' true and false memories. Using the Deese/Roediger-McDermott paradigm and either neutral or negative-emotional lists, both adults' (Experiment 1) and children's (Experiment 2) true recall and recognition was better for neutral than negative items, and although false recall was also higher for neutral items, false recognition was higher for negative items. The last three experiments examined adults' (Experiment 3) and children's (Experiments 4 and 5) 1-week long-term recognition of neutral and negative-emotional information. The results replicated the immediate recall and recognition findings from the first two experiments. More important, these experiments showed that although true recognition decreased over the 1-week interval, false recognition of neutral items remained unchanged whereas false recognition of negative-emotional items increased. These findings are discussed in terms of theories of emotion and memory as well as their forensic implications.
Petta, Salvatore; Vanni, Ester; Bugianesi, Elisabetta; Di Marco, Vito; Cammà, Calogero; Cabibi, Daniela; Mezzabotta, Lavinia; Craxì, Antonio
2015-05-01
The accuracy of noninvasive tools for the diagnosis of severe fibrosis in patients with nonalcoholic fatty liver disease(NAFLD) in clinical practice is still limited. We aimed at assessing the diagnostic performance of combined noninvasive tools in two independent cohorts of Italian NAFLD patients. We analysed data from 321 Italian patients(179 Sicilian-training cohort, and 142 northern Italy-validation cohort) with an histological diagnosis of NAFLD. Severe fibrosis was defined as fibrosis ≥ F3 according to Kleiner classification. The APRI, AST/ALT, BARD, FIB-4, and NFS scores were calculated according to published algorithms. Liver stiffness measurement(LSM) was performed by FibroScan. Cut-off points of LSM, NFS and FIB-4 for rule-in or rule-out F3-F4 fibrosis were calculated by the reported formulas. In the Sicilian cohort AUCs of LSM, NFS, FIB-4, LSM plus NFS, LSM plus FIB-4, and NFS plus FIB-4 were 0.857, 0.803, 0.790, 0.878, 0.888 and 0.807, respectively, while in the northern Italy cohort the corresponding AUCs were 0.848, 0.730, 0.703, 0.844, 0.850, and 0.733 respectively. In the training cohort, the combination of LSM plus NFS was the best performing strategy, providing false positive, false negative and uncertainty area rates of 0%,1.1% and 48% respectively. Similar results were obtained in the validation cohort with false positive, false negative and uncertainty area rates of 0%,7.3% and 40.8%. The combination of LSM with NFS, two complementary, easy-to-perform, and widely available tools, is able to accurately diagnose or exclude the presence of severe liver fibrosis, also reducing of about 50-60% the number of needed diagnostic liver biopsies. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
van der Jagt, E.J.; van Westreenen, H.L.; van Dullemen, H.M.; Kappert, P.; Groen, H.; Sietsma, J.; Oudkerk, M.; Plukker, J.Th.M.; van Dam, G.M.
2009-01-01
Abstract Aim: In this feasibility study we investigated whether magnetic resonance imaging (MRI) with ultrasmall superparamagnetic iron oxide (USPIO) can be used to identify regional and distant lymph nodes, including mediastinal and celiac lymph node metastases in patients with oesophageal cancer. Patients and methods: Ten patients with a potentially curative resectable cancer of the oesophagus were eligible for this study. All patients included in the study had positive lymph nodes on conventional staging (including endoscopic ultrasound, computed tomography and fluorodeoxyglucose-positron emission tomography). Nine patients underwent MRI + USPIO before surgery. Results were restricted to those patients who had both MRI + USPIO and histological examination. Results were compared with conventional staging and histopathologic findings. Results: One patient was excluded due to expired study time. Five out of 9 patients underwent an exploration; in 1 patient prior to surgery MRI + USPIO diagnosed liver metastases and in 3 patients an oesophageal resection was performed. USPIO uptake in mediastinal lymph nodes was seen in 6 out of 9 patients; in 3 patients non-malignant nodes were not visible. In total, 9 lymph node stations (of 6 patients) were separately analysed; 7 lymph node stations were assessed as positive (N1) on MRI+USPIO compared with 9 by conventional staging. According to histology findings, there was one false-positive and one false-negative result in MRI + USPIO. Also, conventional staging modalities had one false-positive and one false-negative result. MRI + USPIO had surplus value in one patient. Not all lymph node stations could be compared due to unforeseen explorations. No adverse effects occurred after USPIO infusion. Conclusion: MRI+USPIO identified the majority of mediastinal and celiac (suspect) lymph nodes in 9 patients with oesophageal cancer. MRI+USPIO could have an additional value in loco-regional staging; however, more supplementary research is needed. PMID:19414293
Garrison, Louis P; Babigumira, Joseph B; Masaquel, Anthony; Wang, Bruce C M; Lalla, Deepa; Brammer, Melissa
2015-06-01
Patients with breast cancer whose tumors test positive for human epidermal growth factor receptor 2 (HER2) are treated with HER2-targeted therapies such as trastuzumab, but limitations with HER2 testing may lead to false-positive (FP) or false-negative (FN) results. To develop a US-level model to estimate the effect of tumor misclassification on health care costs and patient quality-adjusted life-years (QALYs). Decision analysis was used to estimate the number of patients with early-stage breast cancer (EBC) whose HER2 status was misclassified in 2012. FP results were assumed to generate unnecessary trastuzumab costs and unnecessary cases of trastuzumab-related cardiotoxicity. FN results were assumed to save money on trastuzumab, but with a loss of QALYs and greater risk of disease recurrence and its associated costs. QALYs were valued at $100,000 under a net monetary benefit approach. Among 226,870 women diagnosed with EBC in 2012, 3.12% (n = 7,070) and 2.18% (n = 4,955) were estimated to have had FP and FN test results, respectively. Approximately 8400 QALYs (discounted, lifetime) were lost among women not receiving trastuzumab because of FN results. The estimated incremental per-patient lifetime burden of FP or FN results was $58,900 and $116,000, respectively. The implied incremental losses to society were $417 million and $575 million, respectively. HER2 tests result in misclassification and nonoptimal treatment of approximately 12,025 US patients with EBC annually. The total economic societal loss of nearly $1 billion suggests that improvements in HER2 testing accuracy are needed and that further clinical and economic studies are warranted. Copyright © 2015 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.
Gatton, Michelle L; Ciketic, Sadmir; Barnwell, John W; Cheng, Qin; Chiodini, Peter L; Incardona, Sandra; Bell, David; Cunningham, Jane; González, Iveth J
2018-01-01
Malaria rapid diagnostic tests (RDTs) can produce false positive (FP) results in patients with human African trypanosomiasis and rheumatoid factor (RF), but specificity against other infectious agents and immunological factors is largely unknown. Low diagnostic specificity caused by cross-reactivity may lead to over-estimates of the number of malaria cases and over-use of antimalarial drugs, at the cost of not diagnosing and treating the true underlying condition. Data from the WHO Malaria RDT Product Testing Programme was analysed to assess FP rates of 221 RDTs against four infectious agents (Chagas, dengue, Leishmaniasis and Schistosomiasis) and four immunological factors (anti-nuclear antibody, human anti-mouse antibody (HAMA), RF and rapid plasma regain). Only RDTs with a FP rate against clean negative samples less than 10% were included. Paired t-tests were used to compare product-specific FP rates on clean negative samples and samples containing non-Plasmodium infectious agents and immunological factors. Forty (18%) RDTs showed no FP results against any tested infectious agent or immunological factor. In the remaining RDTs significant and clinically relevant increases in FP rates were observed for samples containing HAMA and RF (P<0.001). There were significant correlations between product-matched FP rates for RF and HAMA on all RDT test bands (P<0.001), and FP rates for each infectious agent and immunological factor were also correlated between test bands of combination RDTs (P≤0.002). False positive results against non-Plasmodium infectious agents and immunological factors does not appear to be a universal property of malaria RDTs. However, since many malaria RDTs have elevated FP rates against HAMA and RF positive samples practitioners may need to consider the possibility of false positive results for malaria in patients with conditions that stimulate HAMA or RF.
Performance of two hearing screening protocols in NICU in Shanghai.
Xu, Zheng-Min; Cheng, Wen-Xia; Yang, Xiao-Lin
2011-10-01
To study the sensitivity and specificity of targeted neonatal hearing screening for the single-session distortion product otoacoustic emissions (DPOAE) technique and the combined DPOAE/automated auditory brain-stem response (AABR) technique. 3000 high-risk newborns were studied at Children's Hospital of Fudan University. They were required to take two different screening procedures separately. The first procedure consisted of DPOAE alone and the second consisted of DPOAE combined with the AABR. Based upon the etiology in high-risk babies, they were divided into four groups. In group I there were 670 very-low-birth-weight (VLBW) newborns (1340 ears), and in group II there were 890 preterm babies (1780 ears). 850 babies (1700 ears) suffered from hyperbilirubinemia in group III, whereas 790 babies (1580 ears) with asphyxia were in group IV. The babies in groups II, III, and IV came from the neonatal intensive-care unit (NICU) of our hospital. The study protocols consisted of the DPOAE alone and DPOAE combined with AABR hearing screening at an age of less than 1 month, and a diagnostic stage at the age of 2 months. With single-session DPOAE screening, the referral rate (8% of the NICU babies), the false-positive rate (4.96%) and the false-negative rate (0.8%) were higher. The different etiologies in NICU babies had significantly different referral rates (F-test, p<0.01). A 4.46% referral rate of hyperbilirubinemi babies was much lower. The combined DPOAE/AABR screening technique revealed a referral rate of 5.03%, a false-positive rate of 2% and a false-negative rate of 0.06%. The false-positive rate was well below the suggested 3% of the American Academy of Pediatric. Comparisons of the referral rate, false-positive rate and false-negative rate of two hearing screening protocols (DPOAE alone and combined DPOAE/AABR) revealed significant differences (t-test, p<0.05, p<0.01, p<0.01). 91 infants (3.03% of the NICU babies) who failed the combined DPOAE/AABR screening were confirmed on hearing impairment. Of 22 babies who passed DPOAE screening but failed the AABR screening had a severe to profound hearing loss based on classic ABR. These patients (24% of the NICU babies with hearing losses) with hyperbilirubinemia and asphyxia problems at newborn stage were diagnosed as auditory neuropathy based on evaluations of DPOAE screening passed, abnormal ABR and absent middle-ear muscle reflexes (MMR). Our study demonstrates the use of a combination of DPOAE and AABR testing ensures high sensitivity and acceptable specificity, and predict the AN profile in NICU babies. Our efforts identified 22 NICU babies with auditory neuropathy who hopefully will benefit from early remediation of their hearing deficit. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Diagnosing Abiotic Degradation
The abiotic degradation of chlorinated solvents in ground water can be difficult to diagnose. Under current practice, most of the “evidence” is negative; specifically the apparent disappearance of chlorinated solvents with an accumulation of vinyl chloride, ethane, ethylene, or ...
Acute lymphoblastic leukemia of childhood monitored by bacteriocin and flowcytometry.
Musclow, C E; Farkas-Himsley, H; Weitzman, S S; Herridge, M
1987-04-01
Bacteriocin and flowcytometric analysis of 106 blood samples from children with acute lymphoblastic leukemia were correlated with clinical stages of disease. Bacteriocins interacted selectively with malignant, and not with normal, lymphocytes causing cell cycle perturbation which was rapidly and objectively recorded by the flowcytometer. The patients were grouped as: (A) newly-diagnosed (15); (B) early induction (11); (C) remission with viral infection (7); (D) remission (64); (E) bone marrow relapsed (5); (F) extramedullary relapsed (3); (G) non-malignant pediatric controls (8). Bacteriocin reacted usually with groups A, B, C, E and not with groups D, F and G. Repeated testing correlated well with the clinical status. Blood from 7 patients in remission and from 3 normal individuals, each with transient viral infection, reacted with bacteriocin. A quantitative correlation between peripheral blood blasts or surface markers for ALL and bacteriocin reactivity was not established. Unexpected results were obtained only in 13% (false-positive 11% and false-negative 3%). This test can be recommended for preliminary diagnosis and possibly prognosis of lymphoblastic leukemia and provides means of monitoring progress during chemotherapy.
ERIC Educational Resources Information Center
Hosek, Sybil G.; Lemos, Diana; Harper, Gary W.; Telander, Kyle
2011-01-01
Given the potential for negative psychosocial and medical outcomes following an HIV diagnosis, Project ACCEPT, a 12-session behavioral intervention, was developed and pilot-tested for youth (aged 16-24) newly diagnosed with HIV. Fifty participants recently diagnosed with HIV were enrolled from 4 sites selected through the Adolescent Medicine…
Lin, Jun-Tao; Yang, Xue-Ning; Zhong, Wen-Zhao; Liao, Ri-Qiang; Dong, Song; Nie, Qiang; Weng, Si-Xian; Fang, Xiao-Jing; Zheng, Jun-Yi; Wu, Yi-Long
2016-11-01
The management of non-small cell lung cancer (NSCLC) relies on the tumour-node-metastasis (TNM) stage, and the treatment regimen differs based on the N status. Positron emission tomography-computed tomography (PET-CT) has emerged as a powerful imaging tool for the detection of various cancers with a relatively low false-negative rate. We explored predictors to identify false-negative N2 disease in PET-CT. A total of 284 consecutive cN0 patients with peripheral NSCLC who underwent PET-CT scans followed by curative intent resections were enrolled as a training set to identify predictors of occult N2 metastases by multivariable analysis. The accuracy and cut-off values for the predictors were calculated using a receiver operating characteristic curve. Clinical and pathological data were analysed retrospectively. An additional 151 patients were collected as a test set to validate the results, including the occult N2 rate and accuracy. In total, 8.5% (24/284) PET-CT-diagnosed N0 NSCLC cases had pathologically diagnosed N2 metastases. The SUV max of the primary tumour was a unique independent risk factor for occult N2 NSCLC [P = 0.003, 95% confidence interval = 0.81-0.96, odds ratio (OR) = 0.88]. Occult N2 metastases occurred more frequently in the subcarinal (16/24) and right lower paratracheal lymph nodes (12/24). Accordingly, we divided the patients into two groups by SUV max : the occult N2 rates in the SUV max of <2.6 and SUV max of ≥2.6 groups were 1.0% (1/100) and 12.5% (23/184), respectively (P = 0.001). In the test set, the occult N2 incidence rate was 9.3% (14/151), with the highest rates occurring in the subcarinal (9/14) and right lower paratracheal lymph nodes (6/14). In the two groups defined by SUV max , the occult N2 rates were 4% (2/50) and 11.9% (12/101), respectively. The SUV max of the primary tumour was an independent risk factor for occult N2 metastases in NSCLC patients diagnosed as clinical N0 by PET-CT. SUV max of ≥2.6 of the primary tumour may indicate the risk of N2 metastases, and invasive mediastinal staging techniques or comprehensive therapy should not be ignored in these patients. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
Diagnosis and Treatment of Central Nervous System Infections in the Emergency Department
Dorsett, Maia
2016-01-01
Central nervous system (CNS) infections, including meningitis, encephalitis, and brain abscess, are rare but time-sensitive emergency department (ED) diagnoses. Patients with CNS infection can present to the ED with a host of non-specific signs and symptoms, including headache, fever, altered mental status, and behavioral changes. In meningitis, the classic triad of fever, neck stiffness, and altered mental status occurs in only a minority of patients. Classic physical examination maneuvers, such Kernig’s and Brudzinski’s signs, are relatively insensitive although specific for predicting cerebrospinal fluid (CSF) pleocytosis. Patients with parenchymal involvement, as occurs with encephalitis and brain abscess, may also have focal neurologic deficits or seizures. Neuroimaging and CSF fluid analysis can appear benign early in the course of meningitis and encephalitis, and clinicians should not be falsely reassured. Delaying antibiotic and antiviral therapies negatively impacts outcomes, particularly with bacterial meningitis and herpes simplex virus encephalitis. As with other rare, life-threatening diagnoses encountered in emergency medicine, the diagnosis and treatment of CNS infections requires vigilance and a high index of suspicion based on the history and physical examination which must be confirmed with appropriate imaging and laboratory evaluation. PMID:27741995
Fabregas, N.; Ewig, S.; Torres, A.; El-Ebiary, M.; Ramirez, J.; de la Bellacasa, J. P.; Bauer, T.; Cabello, H.
1999-01-01
BACKGROUND—A study was undertaken to assess the diagnostic value of different clinical criteria and the impact of microbiological testing on the accuracy of clinical diagnosis of suspected ventilator associated pneumonia (VAP). METHODS—Twenty five deceased mechanically ventilated patients were studied prospectively. Immediately after death, multiple bilateral lung biopsy specimens (16 specimens/patient) were obtained for histological examination and quantitative lung cultures. The presence of both histological pneumonia and positive lung cultures was used as a reference test. RESULTS—The presence of infiltrates on the chest radiograph and two of three clinical criteria (leucocytosis, purulent secretions, fever) had a sensitivity of 69% and a specificity of 75%; the corresponding numbers for the clinical pulmonary infection score (CPIS) were 77% and 42%. Non-invasive as well as invasive sampling techniques had comparable values. The combination of all techniques achieved a sensitivity of 85% and a specificity of 50%, and these values remained virtually unchanged despite the presence of previous treatment with antibiotics. When microbiological results were added to clinical criteria, adequate diagnoses originating from microbiological results which might have corrected false positive and false negative clinical judgements (n = 5) were countered by a similar proportion of inadequate diagnoses (n =6). CONCLUSIONS—Clinical criteria had reasonable diagnostic values. CPIS was not superior to conventional clinical criteria. Non-invasive and invasive sampling techniques had diagnostic values comparable to clinical criteria. An algorithm guiding antibiotic treatment exclusively by microbiological results does not increase the overall diagnostic accuracy and carries the risk of undertreatment. PMID:10491448
Evaluation of sensitivity and specificity of cytologic examination: 269 cases (1999-2000).
Cohen, Michele; Bohling, Mark W; Wright, James C; Welles, Elizabeth A; Spano, Joseph S
2003-04-01
To determine sensitivity and specificity of cytologic examination used in a clinical setting. Retrospective study. 216 dogs, 44 cats, 4 horses, 2 ferrets, 1 llama, 1 rat, and 1 mouse. Records were reviewed of cases in which a cytologic diagnosis was followed by a surgical biopsy or postmortem examination within 3 days with subsequent histopathologic diagnosis. Diagnoses were compared for agreement at various levels, including complete agreement, partial agreement, no agreement, or no comparison possible because of insufficient or incorrect cytologic specimen. Levels of agreement were compared for different categories of lesions, including neoplastic, inflammatory, dysplastic-hyperplastic-other, and normal tissue. Additionally, levels of agreement for neoplastic lesions were categorized with regard to cell type, degree of malignancy, and location. Sensitivity and specificity of cytologic examination were calculated. At the level of general agreement (complete and partial agreement), the sensitivity of cytologic examination ranged from 33.3 to 66.1%, depending on the location of the lesion. Cytologic examination was most accurate when used to diagnose cutaneous and subcutaneous lesions and least accurate for diagnosis of liver lesions. Cytologic examination was most effective in diagnosis of neoplastic disease and least effective in diagnosis of dysplastic or hyperplastic conditions. Cytologic examination is a valuable diagnostic tool, although our results indicated lower accuracy than previously reported. False-negative results (missing a diagnosis) were far more common than false-positive results (categorizing a healthy animal as diseased): therefore, if the clinical index of suspicion is high, cytologic examination should be repeated or another technique should be selected to rule out the suspected condition.
[Computed tomography with computer-assisted detection of pulmonary nodules in dogs and cats].
Niesterok, C; Piesnack, S; Köhler, C; Ludewig, E; Alef, M; Kiefer, I
2015-01-01
The aim of this study was to assess the potential benefit of computer-assisted detection (CAD) of pulmonary nodules in veterinary medicine. Therefore, the CAD rate was compared to the detection rates of two individual examiners in terms of its sensitivity and false-positive findings. We included 51 dogs and 16 cats with pulmonary nodules previously diagnosed by computed tomography. First, the number of nodules ≥ 3 mm was recorded for each patient by two independent examiners. Subsequently, each examiner used the CAD software for automated nodule detection. With the knowledge of the CAD results, a final consensus decision on the number of nodules was achieved. The software used was a commercially available CAD program. The sensitivity of examiner 1 was 89.2%, while that of examiner 2 reached 87.4%. CAD had a sensitivity of 69.4%. With CAD, the sensitivity of examiner 1 increased to 94.7% and that of examiner 2 to 90.8%. The CAD-system, which we used in our study, had a moderate sensitivity of 69.4%. Despite its severe limitations, with a high level of false-positive and false-negative results, CAD increased the examiners' sensitivity. Therefore, its supportive role in diagnostics appears to be evident.
Paige F.B. Ferguson; Michael J. Conroy; Jeffrey Hepinstall-Cymerman; Nigel Yoccoz
2015-01-01
False positive detections, such as species misidentifications, occur in ecological data, although many models do not account for them. Consequently, these models are expected to generate biased inference.The main challenge in an analysis of data with false positives is to distinguish false positive and false negative...
Kanda, Seiji; Laimanivong, Sakhone; Shimono, Takaki; Darcy, Andrew Waleluma; Phyaluanglath, Amphay; Mishima, Nobuyuki; Nishiyama, Toshimasa
2017-01-01
We developed a combined conventional polymerase chain reaction (PCR) and real-time PCR (qPCR)-based assay for detecting and discriminating between Opisthorchis viverrini and Haplorchis taichui parasite infections. The first PCR amplifies the mitochondrial cytochrome c oxidase subunit I (COI) genes of parasites, and differential diagnosis is achieved by performing qPCR with specific primers and SYBR Green I. The detection limit of the assay was found to be 2.0 × 102 plasmid copies in a test in which a stool sample was spiked with a single egg, which is equivalent to 5 eggs per gram (EPG). The testing of 34 clinical stool samples that had been demonstrated to contain “Opisthorchis-like” eggs by microscopy showed that the novel assay exhibited a sensitivity of 100% for “Opisthorchis-like” parasitic infections, and 71% and 91% of these samples were found to be infected with O. viverrini and H. taichui, respectively. A further four parasitic infections were diagnosed in the 16 negative samples, and the microscopic findings of these samples were confirmed to be false negatives by sequencing analysis. The assay also displayed high specificity during the testing of 10 samples containing other common parasites. The fact that our qPCR SYBR Green I–based assay detected submicroscopic traces of parasitic DNA and was able to differentiate between parasites that produce eggs with similar morphologies indicates that it has a good potential for development of diagnostic application to use in areas where multiple parasites coexist. PMID:27821695
Cunha, Burke A; Jimada, Ismail
2018-01-01
Fever of unknown origin (FUO) refers to fevers of ≥101° F that persist for ≥3 weeks and remain undiagnosed after a focused inpatient or outpatient workup. FUO may be due to infectious, malignant/neoplastic, rheumatic/inflammatory, or miscellaneous disorders. Recurrent FUOs are due to the same causes of classical FUOs. Recurrent FUOs may have continuous or intermittent fevers and are particularly difficult to diagnose. With intermittent fever, recurrent FUO diagnostic tests are best obtained during fever episodes. With recurrent FUOs, the periodicity of febrile episodes is unpredictable. We present a case of a 70-year-old male who presented with recurrent FUO. Multiple extensive FUO workups failed to determine the source of his fever. During his last two episodes of fever/chills, blood cultures were positive for Enterobacter cloacae. Episodic E. cloacae bacteremias suggested a device-related infection, and the patient had a penile implant and permanent pacemaker (PPM). Following febrile episodes, he was treated with multiple courses of appropriate antibiotics, but subsequently fever/chills recurred. Since a device-associated infection was suspected, indium and PET scans were done, but were negative. The source of his intermittent E. cloacae bacteremias was finally demonstrated by gallium scan showing enhanced uptake on a cardiac lead, but not the penile implant or PPM. Gallium scanning remains useful in workup of FUOs, particularly when false-negative indium or PET scans are suspected. The involved pacemaker lead was explanted, grew E. cloacae and the patient has since remained fever free.
Hahn, Soo Yeon; Shin, Jung Hee; Han, Boo-Kyung; Ko, Eun Young
2011-02-01
Management of suspicious microcalcifications in very thin breasts is problematic. To evaluate whether sonographically-guided vacuum-assisted biopsy (USVAB) with digital mammography-guided skin marking (DM) for the diagnosis of breast microcalcifications is comparable to stereotactic-guided vacuum-assisted biopsy (SVAB) in Asian women with thin breasts. Retrospective review was performed for 263 consecutive suspicious microcalcification lesions in 261 women who underwent USVAB with DM or SVAB using a prone table between January 2004 and December 2007. SVAB was performed for 190 lesions and USVAB for 73 lesions. Biopsy results were correlated with surgical pathology or followed up for at least 12 months. The diagnostic outcomes of SVAB and USVAB to diagnose microcalcifications were compared. Of 263 lesions, 104 (40%) underwent surgery and 159 (60%) were followed up. SVAB and USVAB groups showed similar final categories or the extent of microcalcifications. US visible lesions were 57 (78%) of 73 at USVAB and 14 (10%) of 140 at SVAB. Of 57 US visible lesions at USVAB, 29 (51%) were not found in initial US but were detectable with the help of DM. Specimen radiographs were negative in 2.1% of lesions at SVAB and in 4.1% at USVAB (p=0.4008). The under-estimation rate and false-negative rate were similar in SVAB and USVAB. US with DM facilitates US visibility of microcalcifications. USVAB with DM can produce acceptable biopsy results, as can SVAB, to diagnose breast microcalcifications in patients with thin breasts.
Whitson, Bryan A; Groth, Shawn S; Odell, David D; Briones, Eleazar P; Maddaus, Michael A; D'Cunha, Jonathan; Andrade, Rafael S
2013-05-01
Mediastinal staging in patients with non-small cell lung cancer (NSCLC) with endobronchial ultrasound-guided fine-needle aspiration (EBUS-FNA) requires a high negative predictive value (NPV) (ie, low false negative rate). We provide a conservative calculation of NPV that calls for caution in the interpretation of EBUS results. We retrospectively analyzed our prospectively gathered database (January 2007 to November 2011) to include NSCLC patients who underwent EBUS-FNA for mediastinal staging. We excluded patients with metastatic NSCLC and other malignancies. We assessed FNAs with rapid on-site evaluation (ROSE). The calculation of NPV is NPV = true negatives/true negatives + false negatives. However, this definition ignores nondiagnostic samples. Nondiagnostic samples should be added to the NPV denominator because decisions based on nondiagnostic samples could be flawed. We conservatively calculated NPV for EBUS-FNA as NPV = true negatives/true negatives + false negatives + nondiagnostic. We defined false negatives as negative FNAs but NSCLC-positive surgical biopsy of the same site. Nondiagnostic FNAs were nonrepresentative of lymphoid tissue. We compared diagnostic performance with the inclusion and exclusion of nondiagnostic procedures. We studied 120 patients with NSCLC who underwent EBUS-FNA; 5 patients had false negative findings and 10 additional patients had nondiagnostic results. The NPV with and without inclusion of nondiagnostic samples was 65.9% and 85.3%, respectively. The inclusion of nondiagnostic specimens into the conservative, worst-case-scenario calculation of NPV for EBUS-FNA in NSCLC lowers the NPV from 85.3% to 65.9%. The true NPV is likely higher than 65.9% as few nondiagnostic specimens are false negatives. Caution is imperative for the safe application of EBUS-FNA in NSCLC staging. Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Plipat, Tanarak; Buathong, Rome; Wacharapluesadee, Supaporn; Siriarayapon, Potjaman; Pittayawonganon, Chakrarat; Sangsajja, Chariya; Kaewpom, Thongchai; Petcharat, Sininat; Ponpinit, Teerada; Jumpasri, Jaruphan; Joyjinda, Yutthana; Rodpan, Apaporn; Ghai, Siriporn; Jittmittraphap, Akanitt; Khongwichit, Sarawut; Smith, Duncan R; Corman, Victor M; Drosten, Christian; Hemachudha, Thiravat
2017-01-01
Thailand reported the first Middle East respiratory syndrome (MERS) case on 18 June 2015 (day 4) in an Omani patient with heart condition who was diagnosed with pneumonia on hospital admission on 15 June 2015 (day 1). Two false negative RT-PCR on upper respiratory tract samples on days 2 and 3 led to a 48-hour diagnosis delay and a decision to transfer the patient out of the negative pressure unit (NPU). Subsequent examination of sputum later on day 3 confirmed MERS coronavirus (MERS-CoV) infection. The patient was immediately moved back into the NPU and then transferred to Bamrasnaradura Infectious Disease Institute. Over 170 contacts were traced; 48 were quarantined and 122 self-monitored for symptoms. High-risk close contacts exhibiting no symptoms, and whose laboratory testing on the 12th day after exposure was negative, were released on the 14th day. The Omani Ministry of Health (MOH) was immediately notified using the International Health Regulation (IHR) mechanism. Outbreak investigation was conducted in Oman, and was both published on the World Health Organization (WHO) intranet and shared with Thailand’s IHR focal point. The key to successful infection control, with no secondary transmission, were the collaborative efforts among hospitals, laboratories and MOHs of both countries. PMID:28840828
Muthukumar, Alagarraju; Alatoom, Adnan; Burns, Susan; Ashmore, Jerry; Kim, Anne; Emerson, Brian; Bannister, Edward; Ansari, M Qasim
2015-01-01
To assess the false-positive and false-negative rates of a 4th-generation human immunodeficiency virus (HIV) assay, the Abbott ARCHITECT, vs 2 HIV 3rd-generation assays, the Siemens Centaur and the Ortho-Clinical Diagnostics Vitros. We examined 123 patient specimens. In the first phase of the study, we compared 99 specimens that had a positive screening result via the 3rd-generation Vitros assay (10 positive, 82 negative, and 7 indeterminate via confirmatory immunofluorescent assay [IFA]/Western blot [WB] testing). In the second phase, we assessed 24 HIV-1 RNA-positive (positive result via the nuclear acid amplification test [NAAT] and negative/indeterminate results via the WB test) specimens harboring acute HIV infection. The 4th-generation ARCHITECT assay yielded fewer false-positive results (n = 2) than the 3rd-generation Centaur (n = 9; P = .02) and Vitros (n = 82; P <.001) assays. One confirmed positive case had a false-negative result via the Centaur assay. When specimens from the 24 patients with acute HIV-1 infection were tested, the ARCHITECT assay yielded fewer false-negative results (n = 5) than the Centaur (n = 10) (P = .13) and the other 3rd-generation tests (n = 16) (P = .002). This study indicates that the 4th-generation ARCHITECT HIV assay yields fewer false-positive and false-negative results than the 3rd-generation HIV assays we tested. Copyright© by the American Society for Clinical Pathology (ASCP).
High false-negative rate of anti-HCV among Egyptian patients on regular hemodialysis.
El-Sherif, Assem; Elbahrawy, Ashraf; Aboelfotoh, Atef; Abdelkarim, Magdy; Saied Mohammad, Abdel-Gawad; Abdallah, Abdallah Mahmoud; Mostafa, Sadek; Elmestikawy, Amr; Elwassief, Ahmed; Salah, Mohamed; Abdelbaseer, Mohamed Ali; Abdelwahab, Kouka Saadeldin
2012-07-01
Routine serological testing for hepatitis C virus (HCV) infection among hemodialysis (HD) patients is currently recommended. A dilemma existed on the value of serology because some investigators reported a high rate of false-negative serologic testing. In this study, we aimed to detect the false-negative rate of anti-HCV among Egyptian HD patients. Seventy-eight HD patients, negative for anti-HCV, anti-HIV, and hepatitis B surface antigen, were tested for HCV RNA by reverse transcriptase polymerase chain reaction (RT-PCR). In the next step, the viral load was quantified by real-time PCR in RT-PCR-positive patients. Risk factors for HCV infection, as well as clinical and biochemical indicators of liver disease, were compared between false-negative and true-negative anti-HCV HD patients. The frequency of false-negative anti-HCV was 17.9%. Frequency of blood transfusion, duration of HD, dialysis at multiple centers, and diabetes mellitus were not identified as risk factors for HCV infection. The frequency of false-negative results had a linear relation to the prevalence of HCV infection in the HD units. Timely identification of HCV within dialysis units is needed in order to lower the risk of HCV spread within the HD units. The high false-negative rate of anti-HCV among HD patients in our study justifies testing of a large scale of patients for precious assessment of effectiveness of nucleic acid amplification technology testing in screening HD patient. © 2012 The Authors. Hemodialysis International © 2012 International Society for Hemodialysis.
Zanella, Gloria; Pullini, Serena; Como, Giuseppe; Bazzocchi, Massimo
2014-01-01
Purpose. To quantify the impact of diagnostic confidence on radiological diagnosis with a fuzzy logic-based method. Materials and Methods. Twenty-two oncologic patients with 20 cysts and 30 metastases ≤1 cm in size found at 64-row computed tomography were included. Two readers (R1/R2) expressed diagnoses as a subjective level of confidence P(d) in malignancy within the interval [0,1] rather than on a “crisp” basis (malignant/benign); confidence in benignancy was 1 − p(d). When cross-tabulating data according to the standard of reference, 2 × 2 table cells resulted from the aggregation between p(d)/1 − p(d) and final diagnosis. We then assessed (i) readers diagnostic performance on a fuzzy and crisp basis; (ii) the “divergence” δ(F, C) (%) as a measure of how confidence impacted on crisp diagnosis. Results. Diagnoses expressed with lower confidence increased fuzzy false positives compared to crisp ones (from 0 to 0.2 for R1; from 1 to 2.4 for R2). Crisp/fuzzy accuracy was 94.0%/93.6% (R1) and 94.0/91.6% (R2). δ(F, C) (%) was larger in the case of the less experienced reader (R2) (up to +7.95% for specificity). According to simulations, δ(F, C) (%) was negative/positive depending on the level of confidence in incorrect diagnoses. Conclusion. Fuzzy evaluation shows a measurable effect of uncertainty on radiological diagnoses. PMID:24587815
Visualizing the Bayesian 2-test case: The effect of tree diagrams on medical decision making.
Binder, Karin; Krauss, Stefan; Bruckmaier, Georg; Marienhagen, Jörg
2018-01-01
In medicine, diagnoses based on medical test results are probabilistic by nature. Unfortunately, cognitive illusions regarding the statistical meaning of test results are well documented among patients, medical students, and even physicians. There are two effective strategies that can foster insight into what is known as Bayesian reasoning situations: (1) translating the statistical information on the prevalence of a disease and the sensitivity and the false-alarm rate of a specific test for that disease from probabilities into natural frequencies, and (2) illustrating the statistical information with tree diagrams, for instance, or with other pictorial representation. So far, such strategies have only been empirically tested in combination for "1-test cases", where one binary hypothesis ("disease" vs. "no disease") has to be diagnosed based on one binary test result ("positive" vs. "negative"). However, in reality, often more than one medical test is conducted to derive a diagnosis. In two studies, we examined a total of 388 medical students from the University of Regensburg (Germany) with medical "2-test scenarios". Each student had to work on two problems: diagnosing breast cancer with mammography and sonography test results, and diagnosing HIV infection with the ELISA and Western Blot tests. In Study 1 (N = 190 participants), we systematically varied the presentation of statistical information ("only textual information" vs. "only tree diagram" vs. "text and tree diagram in combination"), whereas in Study 2 (N = 198 participants), we varied the kinds of tree diagrams ("complete tree" vs. "highlighted tree" vs. "pruned tree"). All versions were implemented in probability format (including probability trees) and in natural frequency format (including frequency trees). We found that natural frequency trees, especially when the question-related branches were highlighted, improved performance, but that none of the corresponding probabilistic visualizations did.
GIANT CELL AORTITIS DIAGNOSED WITH PET/CT - PARANEOPLASTIC SYNDROME?
Bakula, Marija; Cerovec, Mislav; Mayer, Miroslav; Huić, Dražen; Anić, Branimir
2016-05-01
Vasculitides are heterogenic group of autoimmune connective tissue diseases which often present difficulties in early diagnosing. Giant cell arteritis is vasculitis of large and medium arteries. It predominantly presents with symptoms of affection of the external carotid artery branches. Furthermore, the only symptoms can be constitutional. In clinical practice, vasculitides are sometimes considered as paraneoplastic, but no definite association with malignancies has been established and the mechanisms are still debated. The gold standard for diagnosing giant cell arteritis is a positive temporal artery biopsy, but the results can often be false negative. Additionally, more than half of the patients have aorta and its main branches affected. Considering aforementioned, imaging studies are essential in confirming large-vessel vasculitis, amongst which is highly sensitive PET/CT. We present the case of a 70-year-old female patient with constitutional symptoms and elevated sedimentation rate. After extensive diagnostic tests, she was admitted to our Rheumatology unit. Aortitis of the abdominal aorta has been confirmed by PET/CT and after the introduction of glucocorticoids the disease soon went into clinical and laboratory remission. Shortly after aortitis has been diagnosed, lung carcinoma was revealed of which the patient died. At the time of the comprehensive diagnostics, there was no reasonable doubt for underlying malignoma. To the best of our knowledge, there are no recent publications concerning giant cell arteritis and neoplastic processes in the context of up-to-date non-invasive diagnostic methods (i.e. PET/CT). In the light of previous research results, we underline that the sensitivity of PET/CT is not satisfactory when estimating cancer dissemination in non-enlarged lymph nodes and that its value can at times be overestimated.
Audit of litigation against the accident and emergency radiology department.
Cantoni, S; De Stefano, F; Mari, A; Savaia, F; Rosso, R; Derchi, L
2009-09-01
The aims of this study were to reduce and monitor litigation due to failure to diagnose a fracture, to evaluate whether the cases were due to radiological error or other problems in the diagnostic and therapeutic management of patients and to identify organisational, technical or functional changes or guidelines to improve the management of patients with suspected fracture and their expectations. We analysed the litigation database for the period 2004-2006 and extracted all episodes indicating failure to diagnose a fracture at the accident and emergency radiology department of our centre. The radiographs underwent blinded review by two experts, and each case was jointly analysed by a radiologist and a forensic physician to see what led to the compensation claim. We identified 22 events (2004 seven cases; 2005 eight cases; 2006 seven cases). Six cases were unrelated to radiological error. Six were due to imperceptible fractures at the time of the examination. These were accounted for by the presence of a major lesion distracting the examiner's attention from a less important associated lesion in one case, a false negative result in a patient examined on a incompletely radiolucent spinal board and underexposure of the coccyx region in an obese patient. Six cases were related to an interpretation error by the radiologist. In the remaining cases, the lesion being referred to in the compensation claim could either not be established or the case was closed by the insurance company without compensation. Corrective measures were adopted. These included planning the purchase of a higher performance device, drawing up a protocol for imaging patients on spinal boards, reminding radiologists of the need to carefully scrutinise the entire radiogram even after having identified a lesion, and producing an information sheet explaining to patients the possibility of false negative results in cases of imperceptible lesions and inviting them to return to the department if symptoms persist. We believe the clinical and administrative analysis we performed is useful. It reviewed some administrative practices and identified critical features. We identified tools that we trust will reduce litigation.
Terterov, Dimitry; Leung, Philemon Ho-Yan; Twells, Laurie K.; Gregory, Deborah M.; Smith, Chris; Boone, Darrell; Pace, David
2017-01-01
Background Although laparoscopic sleeve gastrectomy (LSG) has been shown to be a safe and effective treatment for severe obesity (body mass index ≥ 35), staple line leaks remain a major complication and account for a substantial portion of the procedure’s morbidity and mortality. Many centres performing LSG routinely obtain contrast studies on postoperative day 1 for early detection of staple line leaks. We examined the usefulness of Gastrografin swallow as an early detection test for staple line leaks on postoperative day 1 after LSG as well as the associated costs. Methods We conducted a retrospective review of a prospectively collected database that included 200 patients who underwent LSG for severe obesity between 2011 and 2014. Primary outcome measures were the incidence of staple line leaks and the results of Gastrografin swallow tests. We obtained imaging costs from appropriate hospital departments. Results Gastrografin swallow was obtained on postoperative day 1 for all 200 patients who underwent LSG. Three patients (1.5%) were found to have staple line leaks. Gastrograffin swallows yielded 1 true positive result and 2 false negatives. The false negatives were subsequently diagnosed on computed tomography (CT) scan. The sensitivity of Gastrografin swallow in this study was 33%. For 200 patients, the total direct cost of the Gastrografin swallows was $35 000. Conclusion The use of routine upper gastrointestinal contrast studies for early detection of staple line leaks has low sensitivity and is costly. We recommend selective use of CT instead. PMID:28742012
Terterov, Dimitry; Leung, Philemon Ho-Yan; Twells, Laurie K; Gregory, Deborah M; Smith, Chris; Boone, Darrell; Pace, David
2017-09-01
Although laparoscopic sleeve gastrectomy (LSG) has been shown to be a safe and effective treatment for severe obesity (body mass index ≥ 35), staple line leaks remain a major complication and account for a substantial portion of the procedure's morbidity and mortality. Many centres performing LSG routinely obtain contrast studies on postoperative day 1 for early detection of staple line leaks. We examined the usefulness of Gastrografin swallow as an early detection test for staple line leaks on postoperative day 1 after LSG as well as the associated costs. We conducted a retrospective review of a prospectively collected database that included 200 patients who underwent LSG for severe obesity between 2011 and 2014. Primary outcome measures were the incidence of staple line leaks and the results of Gastrografin swallow tests. We obtained imaging costs from appropriate hospital departments. Gastrografin swallow was obtained on postoperative day 1 for all 200 patients who underwent LSG. Three patients (1.5%) were found to have staple line leaks. Gastrograffin swallows yielded 1 true positive result and 2 false negatives. The false negatives were subsequently diagnosed on computed tomography (CT) scan. The sensitivity of Gastrografin swallow in this study was 33%. For 200 patients, the total direct cost of the Gastrografin swallows was $35 000. The use of routine upper gastrointestinal contrast studies for early detection of staple line leaks has low sensitivity and is costly. We recommend selective use of CT instead.
Mydlo, J H; Hayyeri, M; Macchia, R J
1998-04-01
To compare our results of preoperative corporal cavernosography and retrograde urethrography in penile fractures with the clinical and intraoperative findings. From January to October 1996, 7 cases of penile fracture were diagnosed at our inner city trauma center. All cases were associated with sexual activity and patients underwent preoperative retrograde urethrography and corpus cavernosography with immediate surgical intervention. We found that 2 patients who presented with blood at the meatus had intact urethras, whereas 2 of the 3 patients who had urethral lacerations did not have a bloody meatus. In 2 cases the urethrogram and cavernosogram revealed lacerations that were not initially detected surgically. However, in another 2 cases, the urethrogram and cavernosogram were falsely negative. Two of the seven corporal fractures were bilateral and five were unilateral. On the basis of this small sample, it appears that preoperative cavernosography and retrograde urethrography may show additional sites of tears in the corpora and urethra because hematoma formation may mask some ruptures. However, the presence or absence of a bloody meatus may not necessarily correlate with the status of the urethra, and the urologist also should be wary of a false-negative imaging study. We suggest that all cases of penile fracture be explored surgically, but preferably by a subcoronal degloving incision that allows careful examination of the urethra and corpora. Results of a larger series may determine if the routine use of these imaging modalities is justified intraoperatively.
Reliability of the anterior drawer test, the pivot shift test, and the Lachman test.
Kim, S J; Kim, H K
1995-08-01
In 147 patients with arthroscopically proved chronic injuries of the anterior cruciate ligament, the anterior drawer test, the Lachman test, and the pivot shift test were done before operation under general or spinal anesthesia. Results of the anterior drawer test were positive in 79.6% of the patients, in 98.6% patients having the Lachman test, and in 89.8% of patients having the pivot shift test. In 19 cases (12.9%), arthroscopic examination showed reattachment of the proximally torn end of the anterior cruciate ligament to the posterior cruciate ligament. In these cases, results of the anterior drawer test were positive in 13 patients (68.4%), in 17 (89.5%) patients having the Lachman test, and in 12 patients (63.2%) having the pivot shift test. In 15 cases with a false negative pivot shift test, arthroscopy showed blockage of anterior subluxation of the lateral tibial condyle by a partially functioning portion of the anterior cruciate ligament, which was reattached to the posterior cruciate ligament in 7 cases. In 2 cases with a false negative Lachman test, there was firm reattachment of the torn end of the anterior cruciate ligament to the proximal portion of the posterior cruciate ligament combined with a bucket handle tear of the medial meniscus. The Lachman test was most sensitive in diagnosing chronic injuries of the anterior cruciate ligament. The pivot shift test was also sensitive but was influenced by many factors.
How does negative emotion cause false memories?
Brainerd, C J; Stein, L M; Silveira, R A; Rohenkohl, G; Reyna, V F
2008-09-01
Remembering negative events can stimulate high levels of false memory, relative to remembering neutral events. In experiments in which the emotional valence of encoded materials was manipulated with their arousal levels controlled, valence produced a continuum of memory falsification. Falsification was highest for negative materials, intermediate for neutral materials, and lowest for positive materials. Conjoint-recognition analysis produced a simple process-level explanation: As one progresses from positive to neutral to negative valence, false memory increases because (a) the perceived meaning resemblance between false and true items increases and (b) subjects are less able to use verbatim memories of true items to suppress errors.
False Negative Urine Pregnancy Testing with Complete Molar Pregnancy: An Example of the Hook Effect.
Anderson, Zachary; Larson, Eric; Khan, Muhammad; Bell, Maria
2016-02-01
Gestational trophoblastic disease (GTD) encompasses a group of tumors derived from trophoblasts, which normally form the placenta during pregnancy. Human chorionic gonadotropin (hCG) is a glycoprotein composed of an alpha subunit identical to that of thyroid stimulating hormone (TSH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). Detection of beta-hCG is achievable in both urine and serum samples, proving useful for the detection of normal pregnancy and GTD. However, in the presence of very high levels of beta-hCG, a false negative result may be obtained due to a phenomenon called the "hook effect" or "prozone phenomenon." In certain circumstances, trophoblastic tumors can produce very high levels of beta-hCG, causing misleading results on urine pregnancy testing. A 49-year-old Caucasian female with past medical history pertinent for deep vein thrombosis, ovarian cysts, and osteopenia presented to her internist with report of irregular uterine bleeding for the preceding three months, accompanied by complaints of abdominal bloating, night sweats, and constipation. The patient stated she had completed two negative qualitative urine pregnancy tests and had been seen by both gynecology and gastroenterology, with recommendations to start supplemental estrogen for her symptoms and begin additional fiber intake for irritable bowel syndrome, respectively. Despite negative urine beta-hCG, a quantitative serum beta-hCG was obtained and revealed a level greater than 200,000 international units (IU). The patient was referred to gynecologic oncology and an open abdominal hysterectomy with preservation of her ovaries was performed. Histopathologic examination showed a complete hydatiform mole with no evidence of invasion. The case highlights the importance of clinical judgment in modern medicine, where biochemical methods and imaging modalities have become main stays in diagnosis. As mentioned, there are ways to reduce the incidence of the hook effect, but with added time and cost. Clinicians need to consider the possibility of the hook effect for instances where the clinical picture points to a disease entity despite negative test results. Delaying diagnoses, as illustrated with GTD, has the potential to cause significant morbidity and mortality.
Taylor, Darlene; Durigon, Monica; Davis, Heather; Archibald, Chris; Konrad, Bernhard; Coombs, Daniel; Gilbert, Mark; Cook, Darrel; Krajden, Mel; Wong, Tom; Ogilvie, Gina
2015-03-01
Failure to understand the risk of false-negative HIV test results during the window period results in anxiety. Patients typically want accurate test results as soon as possible while clinicians prefer to wait until the probability of a false-negative is virtually nil. This review summarizes the median window periods for third-generation antibody and fourth-generation HIV tests and provides the probability of a false-negative result for various days post-exposure. Data were extracted from published seroconversion panels. A 10-day eclipse period was used to estimate days from infection to first detection of HIV RNA. Median (interquartile range) days to seroconversion were calculated and probabilities of a false-negative result at various time periods post-exposure are reported. The median (interquartile range) window period for third-generation tests was 22 days (19-25) and 18 days (16-24) for fourth-generation tests. The probability of a false-negative result is 0.01 at 80 days' post-exposure for third-generation tests and at 42 days for fourth-generation tests. The table of probabilities of falsely-negative HIV test results may be useful during pre- and post-test HIV counselling to inform co-decision making regarding the ideal time to test for HIV. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Supporting diagnosis of attention-deficit hyperactive disorder with novelty detection.
Lee, Hyoung-Joo; Cho, Sungzoon; Shin, Min-Sup
2008-03-01
Computerized continuous performance test (CPT) is a widely used diagnostic tool for attention-deficit hyperactivity disorder (ADHD). It measures the number of correctly detected stimuli as well as response times. Typically, when calculating a cut-off score for discriminating between normal and abnormal, only the normal children's data are collected. Then the average and standard deviation of each measure or variable is computed. If any of variables is larger than 2 sigma above the average, that child is diagnosed as abnormal. We will call this approach as "T-score 70" classifier. However, its performance has a lot to be desired due to a high false negative error. In order to improve the classification accuracy we propose to use novelty detection approaches for supporting ADHD diagnosis. Novelty detection is a model building framework where a classifier is constructed using only one class of training data and a new input pattern is classified according to its similarity to the training data. A total of eight novelty detectors are introduced and applied to our ADHD datasets collected from two modes of tests, visual and auditory. They are evaluated and compared with the T-score model on validation datasets in terms of false positive and negative error rates, and area under receiver operating characteristics curve (AuROC). Experimental results show that the cut-off score of 70 is suboptimal which leads to a low false positive error but a very high false negative error. A few novelty detectors such as Parzen density estimators yield much more balanced classification performances. Moreover, most novelty detectors outperform the T-score method for most age groups statistically with a significance level of 1% in terms of AuROC. In particular, we recommend the Parzen and Gaussian density estimators, kernel principal component analysis, one-class support vector machine, and K-means clustering novelty detector which can improve upon the T-score method on average by at least 30% for the visual test and 40% for the auditory test. In addition, their performances are relatively stable over various parameter values as long as they are within reasonable ranges. The proposed novelty detection approaches can replace the T-score method which has been considered the "gold standard" for supporting ADHD diagnosis. Furthermore, they can be applied to other psychological tests where only normal data are available.
Real-Life Clinical Practice of Using the Xpert MTB/RIF Assay in Thailand.
Kawkitinarong, Kamon; Suwanpimolkul, Gompol; Kateruttanakul, Pairaj; Manosuthi, Weerawat; Ubolyam, Sasiwimol; Sophonphan, Jiratchaya; Avihingsanon, Anchalee; Ruxrungtham, Kiat
2017-05-15
Delayed diagnosis of tuberculosis (TB) and drug-resistant TB are major challenges of TB control in Thailand. This study assessed the practicality of the Xpert MTB/RIF assay in a real-life setting with high prevalence of human immunodeficiency virus (HIV) infection and pulmonary tuberculosis (PTB). This prospective study was conducted at 3 large tertiary care hospitals. Patients who had suspected PTB were enrolled into the study. Expectorated sputum samples were sent for staining, mycobacterial culture, and Xpert MTB/RIF. Four hundred ninety-four patients were enrolled. From 355 cases with final diagnosis of PTB, 263 (71.8%) had definite diagnosis and 92 cases had probable diagnosis. Among TB culture-positive cases, Xpert MTB/RIF had 100% and 81% sensitivity in sputum smear-positive and smear-negative groups, respectively. The specificity was 95.7%. The sensitivity and positive predictive value of Xpert MTB/RIF in culture-negative but clinically diagnosed PTB was 37.8% and 83.8%, respectively. Centrifugation was required in 59% cases with scanty sputum. Five cases were false-positive by Xpert MTB/RIF in patients with nontuberculous mycobacteria, old PTB scar, and immune reconstitution syndrome. Discordant rifampicin susceptibility results of Xpert MTB/RIF and mycobacteria growth indicator tube (MGIT) were confirmed by using rpoB gene sequencing, which raised the sensitivity of Xpert MTB/RIF in detecting rifampicin resistance to 93.8%. Xpert MTB/RIF is an effective tool in diagnosing PTB but will be more cost-effective for sputum-negative patients and in settings with high prevalence of rifampicin resistance. Early diagnosis of TB results in early treatment and implementation of strategies to limit spreading of TB. Sputum centrifugation may increase the yield of Xpert MTB/RIF. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
Lee-Felker, Stephanie A; Tekchandani, Leena; Thomas, Mariam; Gupta, Esha; Andrews-Tang, Denise; Roth, Antoinette; Sayre, James; Rahbar, Guita
2017-11-01
Purpose To compare the diagnostic performances of contrast material-enhanced spectral mammography and breast magnetic resonance (MR) imaging in the detection of index and secondary cancers in women with newly diagnosed breast cancer by using histologic or imaging follow-up as the standard of reference. Materials and Methods This institutional review board-approved, HIPAA-compliant, retrospective study included 52 women who underwent breast MR imaging and contrast-enhanced spectral mammography for newly diagnosed unilateral breast cancer between March 2014 and October 2015. Of those 52 patients, 46 were referred for contrast-enhanced spectral mammography and targeted ultrasonography because they had additional suspicious lesions at MR imaging. In six of the 52 patients, breast cancer had been diagnosed at an outside institution. These patients were referred for contrast-enhanced spectral mammography and targeted US as part of diagnostic imaging. Images from contrast-enhanced spectral mammography were analyzed by two fellowship-trained breast imagers with 2.5 years of experience with contrast-enhanced spectral mammography. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value were calculated for both imaging modalities and compared by using the Bennett statistic. Results Fifty-two women with 120 breast lesions were included for analysis (mean age, 50 years; range, 29-73 years). Contrast-enhanced spectral mammography had similar sensitivity to MR imaging (94% [66 of 70 lesions] vs 99% [69 of 70 lesions]), a significantly higher PPV than MR imaging (93% [66 of 71 lesions] vs 60% [69 of 115 lesions]), and fewer false-positive findings than MR imaging (five vs 45) (P < .001 for all results). In addition, contrast-enhanced spectral mammography depicted 11 of the 11 secondary cancers (100%) and MR imaging depicted 10 (91%). Conclusion Contrast-enhanced spectral mammography is potentially as sensitive as MR imaging in the evaluation of extent of disease in newly diagnosed breast cancer, with a higher PPV. © RSNA, 2017.
[Solitary nodular sarcoidosis demonstrating reversed tuberculin skin reaction].
Osoreda, Hisayuki; Kobayashi, Hideo; Kanoh, Soichiro; Motoyoshi, Kazuo
2008-08-01
A 29-year-old woman was admitted because of chest radiograph abnormality. She had no respiratory complaints. Chest CT demonstrated an ill-defined nodule of 20mm with the "sarcoid galaxy sign" in the right upper lobe. Transbronchial biopsy (TBB) specimens from right S2 revealed non-caseating epithelioid cell granuloma. Initial clinical findings suggested mycobacterial infection. However, while waiting for the results of mycobacterial cultures in bronchial washing fluid, the tuberculin skin reaction was found to be negative, and enlargement of nodule, mediastinal lymphadenopathy and elevated soluble IL-2R were observed. Cultures for mycobacterium were negative and repeat TBB specimens revealed granulomatous inflammation. We diagnosed with sarcoidosis based on these findings. Solitary nodular sarcoidosis is rare with only 17 cases having been reported. These cases were diagnosed with difficulty because of non-specific clinical findings and of the 17, 16 cases (94%) were diagnosed by surgical procedures. We observed the clinico-radiological course of solitary nodules and the change in tuberculin reaction. Although a negative tuberculin skin reaction was commonly recognized in sarcoidosis patients, we confirmed that initial positive tuberculin reaction changed to negative according to disease progress. To the best of our knowledge, this is the first case report in adults.
Discrete emotion-congruent false memories in the DRM paradigm.
Bland, Cassandra E; Howe, Mark L; Knott, Lauren
2016-08-01
Research has shown that false-memory production is enhanced for material that is emotionally congruent with the mood of the participant at the time of encoding. So far this research has only been conducted to examine the influence of generic negative affective mood states and generic negative stimuli on false-memory production. In addition, much of the research is limited as it focuses on valence and arousal dimensions, and fails to take into account the more comprehensive nature of emotions. The current study demonstrates that this effect goes beyond general negative or positive moods and acts at a more discrete emotional level. Participants underwent a standard emotion-induction procedure before listening to negative emotional or neutral associative word lists. The emotions induced, negative word lists, and associated nonpresented critical lures, were related to either fear or anger, 2 negative valence emotions that are also both high in arousal. Results showed that when valence and arousal are controlled for, false memories are more likely to be produced for discrete emotionally congruent compared with incongruent materials. These results support spreading activation theories of false remembering and add to our understanding of the adaptive nature of false-memory production. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Stirling, Paul; Faroug, Radwane; Amanat, Suheil; Ahmed, Abdulkhaled; Armstrong, Malcolm; Sharma, Pankaj; Qamruddin, Ahmed
2014-01-01
We quantify the false-negative diagnostic rate of septic arthritis using Gram-stain microscopy of synovial fluid and compare this to values reported in the peer-reviewed literature. We propose a method of improving the diagnostic value of Gram-stain microscopy using Lithium Heparin containers that prevent synovial fluid coagulation. Retrospective study of the Manchester Royal Infirmary microbiology database of patients undergoing synovial fluid Gram-stain and culture between December 2003 and March 2012 was undertaken. The initial cohort of 1896 synovial fluid analyses for suspected septic arthritis was reduced to 143 after exclusion criteria were applied. Analysis of our Gram-stain microscopy yielded 111 false-negative results from a cohort size of 143 positive synovial fluid cultures, giving a false-negative rate of 78%. We report a false-negative rate of Gram-stain microscopy for septic arthritis of 78%. Clinicians should therefore avoid the investigation until a statistically significant data set confirms its efficacy. The investigation's value could be improved by using Lithium Heparin containers to collect homogenous synovial fluid samples. Ongoing research aims to establish how much this could reduce the false-negative rate.
Lee, Jaehee; Lee, Shin Yup; Yoo, Seung Soo; Cha, Seung Ick; Won, Dong Il; Park, Jae Yong; Lee, Won-Kil; Kim, Chang Ho
2012-07-01
Combining a polymerase chain reaction (PCR) test with bronchoscopy is frequently performed to allow a rapid diagnosis of smear-negative pulmonary tuberculosis (PTB). However, limited data are available concerning clinical judgment in patients with suspected PTB and AFB smear- and PCR-negative bronchial aspirates (BA). The present study evaluated the usefulness of whole-blood QuantiFERON-TB Gold In-Tube (QFT) testing in these patients. Of 166 patients with suspected PTB who had undergone bronchoscopy because of smear-negative sputum or inadequate sputum production, 93 (56%) were diagnosed with culture-positive PTB. Seventy-four patients were either AFB smear- or PCR-positive. In the 75 patients whose BA AFB smear and PCR results were both negative, 19 were finally diagnosed with PTB by culture. The QFT test had a negative predictive value of 91% for PTB. The QFT test may be useful for excluding PTB in patients with suspected PTB whose BA AFB smear and PCR results are both negative. Copyright © 2012 Elsevier Inc. All rights reserved.
Feil, Katharina; Feuerecker, Regina; Goldschagg, Nicolina; Strobl, Ralf; Brandt, Thomas; von Müller, Albrecht; Grill, Eva; Strupp, Michael
2018-01-01
Making the correct diagnosis of patients presenting with vertigo and dizziness in clinical practice is often challenging. In this study we examined the performance of the iPad based program me d x in the prediction of different clinical vertigo and dizziness diagnoses and as a diagnostic tool to distinguish between them. The data collection was done in the outpatient clinic of the German Center of Vertigo and Balance Disorders. The "gold standard diagnosis" was defined as the clinical diagnosis of the specialist during the visit of the patient based on standardized history and clinical examination. Another independent and blinded physician finalized each patient's case in the constellatory diagnostic system of me d x based on an algorithm using all available clinical information. These diagnoses were compared to the "gold standard" by retrospective review of the charts of the patients. The accuracy provided by me d x was defined as the number of correctly classified diagnoses. In addition, the probability of being test positive when a disease was present (sensitivity), of being test negative when a disease was absent (specificity), of having the disease when the test is positive (positive predictive value) and of not having the disease when the test is negative (negative predictive value) for the most common diagnoses were reported. Sixteen possible different vertigo and dizziness diagnoses could be provided by me d x. A total of 610 patients (mean age 58.1 ± 16.3 years, 51.2% female) were included. The accuracy for the most common diagnoses was between 82.1 and 96.6% with a sensitivity of 40 to 80.5% and a specificity of more than 80%. When analyzing the quality of me d x in a multiclass problem for the six most common clinical diagnoses, the sensitivity, specificity, positive and negative predictive values were as follows: Bilateral vestibulopathy (81.6, 97.1, 71.1, and 97.5%), Menière's disease (77.8, 97.6, 87.0, and 95.3%), benign paroxysmal positional vertigo (61.7, 98.3, 86.6, and 93.4%), downbeat nystagmus syndrome (69.6, 97.7, 71.1, and 97.5%), vestibular migraine (34.7, 97.8, 76.1, and 88.3%), and phobic postural vertigo (80.5, 82.5, 52.5, and 94.6%). This study demonstrates that me d x is a new and easy approach to screen for different diagnoses. With the high specificity and negative predictive value, the system helps to rule out differential diagnoses and can therefore also lead to a cost reduction in the health care system. However, the sensitivity was unexpectedly low, especially for vestibular migraine. All in all, this device can only be a complementary tool, in particular for non-experts in the field.
Tantilipikorn, Pongsakorn; Danpornprasert, Piyanart; Ngaotepprutaram, Premyot; Assanasen, Paraya; Bunnag, Chaweewan; Thinkhamrop, Bandit
2015-12-01
Diagnosis of allergic rhinitis (AR) is based on history, physical examination, and skin prick test (SPT) while intradermal (ID) test can be performed to confirm the diagnosis in case of negative result of SPT. However, the ID test is not recommended for cat and timothy grass allergy because of its high false positive rate. As a result, the "quantitative" technique of serum specific IgE (sIgE) measurement might be helpful to diagnose AR with more confidence. To evaluate the correlation between ID tests and sIgE in the diagnosis of house dust mite (HDM)-sensitive AR patients. Patients with chronic rhinitis (CR) were recruited and SPT was performed. If SPT was negative, ID test and sIgE to HDM [Dermatophagoides pteronyssinus (Dp)] measurement were performed. Eighty-two patients with chronic rhinitis (CR), whose SPTs were negative for Dp, were included. There were 39 males (47.6%) and 43 females (52.4%) aged between 18 and 76 years old (mean age = 43.3 years). The ID test was positive in 13 patients (15.9%), and was negative in 69 patients (84.1 %). sIgE to HDM was positive ( ≥ 0.35 kUA/l) in 2 patients (2.4%). There was a fair to moderate correlation between the size of wheal of ID test and sIgE to HDM (r = 0.44, 95% confidence interval: 0.19 to 0.67, p < 0.01). ID test has a fair to moderate correlation with sIgE Dermatophagoides pteronyssinus and it can be used in CR patients with negative SPT where sIgE is not feasible.
Patient characteristics associated with false arrhythmia alarms in intensive care.
Harris, Patricia R; Zègre-Hemsey, Jessica K; Schindler, Daniel; Bai, Yong; Pelter, Michele M; Hu, Xiao
2017-01-01
A high rate of false arrhythmia alarms in the intensive care unit (ICU) leads to alarm fatigue, the condition of desensitization and potentially inappropriate silencing of alarms due to frequent invalid and nonactionable alarms, often referred to as false alarms. The aim of this study was to identify patient characteristics, such as gender, age, body mass index, and diagnosis associated with frequent false arrhythmia alarms in the ICU. This descriptive, observational study prospectively enrolled patients who were consecutively admitted to one of five adult ICUs (77 beds) at an urban medical center over a period of 31 days in 2013. All monitor alarms and continuous waveforms were stored on a secure server. Nurse scientists with expertise in cardiac monitoring used a standardized protocol to annotate six clinically important types of arrhythmia alarms (asystole, pause, ventricular fibrillation, ventricular tachycardia, accelerated ventricular rhythm, and ventricular bradycardia) as true or false. Total monitoring time for each patient was measured, and the number of false alarms per hour was calculated for these six alarm types. Medical records were examined to acquire data on patient characteristics. A total of 461 unique patients (mean age =60±17 years) were enrolled, generating a total of 2,558,760 alarms, including all levels of arrhythmia, parameter, and technical alarms. There were 48,404 hours of patient monitoring time, and an average overall alarm rate of 52 alarms/hour. Investigators annotated 12,671 arrhythmia alarms; 11,345 (89.5%) were determined to be false. Two hundred and fifty patients (54%) generated at least one of the six annotated alarm types. Two patients generated 6,940 arrhythmia alarms (55%). The number of false alarms per monitored hour for patients' annotated arrhythmia alarms ranged from 0.0 to 7.7, and the duration of these false alarms per hour ranged from 0.0 to 158.8 seconds. Patient characteristics were compared in relation to 1) the number and 2) the duration of false arrhythmia alarms per 24-hour period, using nonparametric statistics to minimize the influence of outliers. Among the significant associations were the following: age ≥60 years ( P =0.013; P =0.034), confused mental status ( P <0.001 for both comparisons), cardiovascular diagnoses ( P <0.001 for both comparisons), electrocardiographic (ECG) features, such as wide ECG waveforms that correspond to ventricular depolarization known as QRS complex due to bundle branch block (BBB) ( P =0.003; P =0.004) or ventricular paced rhythm ( P =0.002 for both comparisons), respiratory diagnoses ( P =0.004 for both comparisons), and support with mechanical ventilation, including those with primary diagnoses other than respiratory ones ( P <0.001 for both comparisons). Patients likely to trigger a higher number of false arrhythmia alarms may be those with older age, confusion, cardiovascular diagnoses, and ECG features that indicate BBB or ventricular pacing, respiratory diagnoses, and mechanical ventilatory support. Algorithm improvements could focus on better noise reduction (eg, motion artifact with confused state) and distinguishing BBB and paced rhythms from ventricular arrhythmias. Increasing awareness of patient conditions that apparently trigger a higher rate of false arrhythmia alarms may be useful for reducing unnecessary noise and improving alarm management.
Chapin, Kimberle C.; Blake, Patricia; Wilson, Claire D.
2002-01-01
Group A streptococcus (GAS) antigen testing has become a routine point-of-care (POC) test in acute care settings. Concern about performance parameters (PP) of these tests as well as inappropriate antibiotic use has resulted in various recommendations regarding diagnosis of GAS. There were two objectives in this study. The first was to evaluate the rapid GAS antigen test presently in use (Thermo BioStar, Boulder, Colo.) and the GAS Direct probe test (Gen-Probe, San Diego, Calif.) compared to culture. The second was to define the optimal use of these technologies in a large acute care pediatric clinic. A total of 520 consecutive pediatric patients presenting with symptoms of pharyngitis at any of three Lahey Clinic acute care facilities were evaluated. Pharyngeal specimens were collected using a double-swab collection device (Copan, Corona, Calif.). One swab was used for the antigen test, the second was used for the probe test, and the pledget was placed in the collection device for culture on 5% sheep blood agar, incubated for 48 h anaerobically, and subsequently placed in Todd-Hewitt broth. After discrepant analysis, sensitivity, specificity, and positive and negative predictive values were as follows: 94.8, 100, 100, and 96.9% for the probe test and 86.1, 97.1, 93.7, and 93.4% for the antigen test, respectively. Sensitivity using an enhanced culture technique was 99.4% (163 of 164). False-positive (FP) antigen results were often seen from patients previously diagnosed and/or treated for GAS. No FP results were seen with the probe test. Colony counts for the false-negative (FN) antigen tests were higher than those for the FN probe tests. Compared to culture and DNA probe, the rapid antigen test (RAT) offered a result at the time of the patient's visit, with acceptable PP when prevalence of disease is high. Follow-up testing with the RAT of GAS patients who previously tested as positive should be avoided due to increased FP results. The probe test was comparable to culture in performance. Results indicate the probe test can be used as the primary test or as a backup to negative antigen tests. The probe test offers the advantage over culture of same-day reporting of a final result but, in contrast to a POC test, necessitates follow-up communication to the patient. Preliminary data show the specificity of the probe test to be greater than that of the RAT for patients previously diagnosed with GAS. PMID:12409399
Yoon, Jung Hyun; Jung, Hae Kyoung; Lee, Jong Tae; Ko, Kyung Hee
2013-09-01
To investigate the factors that have an effect on false-positive or false-negative shear-wave elastography (SWE) results in solid breast masses. From June to December 2012, 222 breast lesions of 199 consecutive women (mean age: 45.3 ± 10.1 years; range, 21 to 88 years) who had been scheduled for biopsy or surgical excision were included. Greyscale ultrasound and SWE were performed in all women before biopsy. Final ultrasound assessments and SWE parameters (pattern classification and maximum elasticity) were recorded and compared with histopathology results. Patient and lesion factors in the 'true' and 'false' groups were compared. Of the 222 masses, 175 (78.8 %) were benign, and 47 (21.2 %) were malignant. False-positive rates of benign masses were significantly higher than false-negative rates of malignancy in SWE patterns, 36.6 % to 6.4 % (P < 0.001). Among both benign and malignant masses, factors showing significance among false SWE features were lesion size, breast thickness and lesion depth (all P < 0.05). All 47 malignant breast masses had SWE images of good quality. False SWE features were more significantly seen in benign masses. Lesion size, breast thickness and lesion depth have significance in producing false results, and this needs consideration in SWE image acquisition. • Shear-wave elastography (SWE) is widely used during breast imaging • At SWE, false-positive rates were significantly higher than false-negative rates • Larger size, breast thickness, depth and fair quality influences false-positive SWE features • Smaller size, larger breast thickness and depth influences false-negative SWE features.
Gómez Palacios, Angel; Gómez Zábala, Jesús; Gutiérrez, María Teresa; Expósito, Amaya; Barrios, Borja; Zorraquino, Angel; Taibo, Miguel Angel; Iturburu, Ignacio
2006-12-01
1. To assess the sensitivity of scintigraphy using methoxy isobutyl isonitrile (MIBI). 2. To compare its resolution with that of ultrasound (US) and computerized axial tomography (CAT). 3. To use its diagnostic reliability to determine whether selective approaches can be used to treat hyperparathyroidism (HPT). A study of 76 patients who underwent surgery for HPT between 1996 and 2005 was performed. MIBI scintigraphy and cervical US were used for whole-body scanning in all patients; CAT was used in 47 patients. Intraoperative and postoperative biopsies were used for final evaluation of the tests, after visualization and surgical extirpation. The results of scintigraphy were positive in 65 patients (85.52%). The diagnosis was correct in all of the single images. Multiple images were due to hyperplasia and parathyroid adenomas with thyroid disease (5.2%). Three images, incorrectly classified as negative (3.94%), were positive. The sensitivity of US was 63% and allowed detection of three MIBI-negative adenomas (4%). CAT was less sensitive (55%), but detected a further three MIBI-negative adenomas (4%). 1. The sensitivity of MIBI reached 89.46%. In the absence of thyroid nodules, MIBI diagnosed 100% of single lesions. Pathological thyroid processes produced false-positive results (5.2%) and there were diagnostic errors (4%). 2. MIBI scintigraphy was more sensitive than US and CAT. 3. Positive, single image scintigraphy allows a selective cervical approach. US and CAT may help to save a further 8% of patients (with negative scintigraphy).
Intracranial pressure and cerebral perfusion pressure in patients developing brain death.
Salih, Farid; Holtkamp, Martin; Brandt, Stephan A; Hoffmann, Olaf; Masuhr, Florian; Schreiber, Stephan; Weissinger, Florian; Vajkoczy, Peter; Wolf, Stefan
2016-08-01
We investigated whether a critical rise of intracranial pressure (ICP) leading to a loss of cerebral perfusion pressure (CPP) could serve as a surrogate marker of brain death (BD). We retrospectively analyzed ICP and CPP of patients in whom BD was diagnosed (n = 32, 16-79 years). Intracranial pressure and CPP were recorded using parenchymal (n = 27) and ventricular probes (n = 5). Data were analyzed from admission until BD was diagnosed. Intracranial pressure was severely elevated (mean ± SD, 95.5 ± 9.8 mm Hg) in all patients when BD was diagnosed. In 28 patients, CPP was negative at the time of diagnosis (-8.2 ± 6.5 mm Hg). In 4 patients (12.5%), CPP was reduced but not negative. In these patients, minimal CPP was 4 to 18 mm Hg. In 1 patient, loss of CPP occurred 4 hours before apnea completed the BD syndrome. Brain death was universally preceded by a severe reduction of CPP, supporting loss of cerebral perfusion as a critical step in BD development. Our data show that a negative CPP is neither sufficient nor a prerequisite to diagnose BD. In BD cases with positive CPP, we speculate that arterial blood pressure dropped below a critical closing pressure, thereby causing cessation of cerebral blood flow. Copyright © 2016 Elsevier Inc. All rights reserved.
The problem of false positives and false negatives in violent video game experiments.
Ferguson, Christopher J
The problem of false positives and negatives has received considerable attention in behavioral research in recent years. The current paper uses video game violence research as an example of how such issues may develop in a field. Despite decades of research, evidence on whether violent video games (VVGs) contribute to aggression in players has remained mixed. Concerns have been raised in recent years that experiments regarding VVGs may suffer from both "false positives" and "false negatives." The current paper examines this issue in three sets of video game experiments, two sets of video game experiments on aggression and prosocial behaviors identified in meta-analysis, and a third group of recent null studies. Results indicated that studies of VVGs and aggression appear to be particularly prone to false positive results. Studies of VVGs and prosocial behavior, by contrast are heterogeneous and did not demonstrate any indication of false positive results. However, their heterogeneous nature made it difficult to base solid conclusions on them. By contrast, evidence for false negatives in null studies was limited, and little evidence emerged that null studies lacked power in comparison those highlighted in past meta-analyses as evidence for effects. These results are considered in light of issues related to false positives and negatives in behavioral science more broadly. Copyright © 2017 Elsevier Ltd. All rights reserved.
Brook, Gary
2015-12-01
To identify point-of-care (POC) and rapid nucleic acid amplification techniques (NAATs) for the diagnosis of chlamydia and gonorrhoea and assess their utility. Literature search for available POC and rapid NAATs. The performance from the best-performing assays were applied hypothetically to patients in the clinic in which 100 consecutive patients with chlamydia and 100 with gonorrhoea were diagnosed in 1737 and 4575 patients respectively, with 44/100 and 54/100 treated at first attendance, respectively. 11 POC and 1 rapid NAAT were identified. Published performances for the best POC for chlamydia (CRT) were: sensitivity 41%-87%, specificity 89%-99.6%. Our data suggest that if this assay was used instead of our current NAAT, for every 100 patients diagnosed currently, 23-46 extra patients would be treated at first attendance; 10-35 would go undiagnosed with 7-191 false-positives. Best chlamydia rapid NAAT (GeneXpert): sensitivity 97.5%-98.7%, specificity 99.4%-99.9%. Anticipated performance for every 100 patients diagnosed currently: 0 extra patients treated at first attendance, 1-3 undiagnosed, 0-2 false-positives. Best POC for gonorrhoea (GC Check): sensitivity 54%-70%, specificity 97%-98%. Anticipated performance for every 100 patients diagnosed currently: 14-18 extra patients treated at first attendance, 28-32 undiagnosed, 92-137 false-positives. Best rapid NAAT for gonorrhoea (GeneXpert): sensitivity 96%-100%, specificity 99.9%-100%. Anticipated performance for every 100 patients diagnosed currently: 0 extra patients treated at first attendance, 0-4 undiagnosed, 0-5 false-positives. Rapid NAAT would reduce time to treatment by 4 days for initially untreated patients. POC assays would need to be used in conjunction with a NAAT, increasing early treatment rates expense and false-positive results. The rapid NAAT could be used alone, with a reduction in average time-to-treat and a small reduction in sensitivity and specificity. 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/
A critical reappraisal of false negative sentinel lymph node biopsy in melanoma.
Manca, G; Romanini, A; Rubello, D; Mazzarri, S; Boni, G; Chiacchio, S; Tredici, M; Duce, V; Tardelli, E; Volterrani, D; Mariani, G
2014-06-01
Lymphatic mapping and sentinel lymph node biopsy (SLNB) have completely changed the clinical management of cutaneous melanoma. This procedure has been accepted worldwide as a recognized method for nodal staging. SLNB is able to accurately determine nodal basin status, providing the most useful prognostic information. However, SLNB is not a perfect diagnostic test. Several large-scale studies have reported a relatively high false-negative rate (5.6-21%), correctly defined as the proportion of false-negative results with respect to the total number of "actual" positive lymph nodes. The main purpose of this review is to address the technical issues that nuclear physicians, surgeons, and pathologists should carefully consider to improve the accuracy of SLNB by minimizing its false-negative rate. In particular, SPECT/CT imaging has demonstrated to be able to identify a greater number of sentinel lymph nodes (SLNs) than those found by planar lymphoscintigraphy. Furthermore, a unique definition in the international guidelines is missing for the operational identification of SLNs, which may be partly responsible for this relatively high false-negative rate of SLNB. Therefore, it is recommended for the scientific community to agree on the radioactive counting rate threshold so that the surgeon can be better radioguided to detect all the lymph nodes which are most likely to harbor metastases. Another possible source of error may be linked to the examination of the harvested SLNs by conventional histopathological methods. A more careful and extensive SLN analysis (e.g. molecular analysis by RT-PCR) is able to find more positive nodes, so that the false-negative rate is reduced. Older age at diagnosis, deeper lesions, histologic ulceration, head-neck anatomical location of primary lesions are the clinical factors associated with false-negative SLNBs in melanoma patients. There is still much controversy about the clinical significance of a false-negative SLNB on the prognosis of melanoma patients. Indeed, most studies have failed to show that there is worse melanoma-specific survival for false-negative compared to true-positive SLNB patients.
van der Meulen, Miriam P; Lansdorp-Vogelaar, Iris; van Heijningen, Else-Mariëtte B; Kuipers, Ernst J; van Ballegooijen, Marjolein
2016-06-01
If some adenomas do not bleed over several years, they will cause systematic false-negative fecal immunochemical test (FIT) results. The long-term effectiveness of FIT screening has been estimated without accounting for such systematic false-negativity. There are now data with which to evaluate this issue. The authors developed one microsimulation model (MISCAN [MIcrosimulation SCreening ANalysis]-Colon) without systematic false-negative FIT results and one model that allowed a percentage of adenomas to be systematically missed in successive FIT screening rounds. Both variants were adjusted to reproduce the first-round findings of the Dutch CORERO FIT screening trial. The authors then compared simulated detection rates in the second screening round with those observed, and adjusted the simulated percentage of systematically missed adenomas to those data. Finally, the authors calculated the impact of systematic false-negative FIT results on the effectiveness of repeated FIT screening. The model without systematic false-negativity simulated higher detection rates in the second screening round than observed. These observed rates could be reproduced when assuming that FIT systematically missed 26% of advanced and 73% of nonadvanced adenomas. To reduce the false-positive rate in the second round to the observed level, the authors also had to assume that 30% of false-positive findings were systematically false-positive. Systematic false-negative FIT testing limits the long-term reduction of biennial FIT screening in the incidence of colorectal cancer (35.6% vs 40.9%) and its mortality (55.2% vs 59.0%) in participants. The results of the current study provide convincing evidence based on the combination of real-life and modeling data that a percentage of adenomas are systematically missed by repeat FIT screening. This impairs the efficacy of FIT screening. Cancer 2016;122:1680-8. © 2016 American Cancer Society. © 2016 American Cancer Society.
Negative feedback from maternal signals reduces false alarms by collectively signalling offspring.
Hamel, Jennifer A; Cocroft, Reginald B
2012-09-22
Within animal groups, individuals can learn of a predator's approach by attending to the behaviour of others. This use of social information increases an individual's perceptual range, but can also lead to the propagation of false alarms. Error copying is especially likely in species that signal collectively, because the coordination required for collective displays relies heavily on social information. Recent evidence suggests that collective behaviour in animals is, in part, regulated by negative feedback. Negative feedback may reduce false alarms by collectively signalling animals, but this possibility has not yet been tested. We tested the hypothesis that negative feedback increases the accuracy of collective signalling by reducing the production of false alarms. In the treehopper Umbonia crassicornis, clustered offspring produce collective signals during predator attacks, advertising the predator's location to the defending mother. Mothers signal after evicting the predator, and we show that this maternal communication reduces false alarms by offspring. We suggest that maternal signals elevate offspring signalling thresholds. This is, to our knowledge, the first study to show that negative feedback can reduce false alarms by collectively behaving groups.
False positives in psychiatric diagnosis: implications for human freedom.
Wakefield, Jerome C
2010-02-01
Current symptom-based DSM and ICD diagnostic criteria for mental disorders are prone to yielding false positives because they ignore the context of symptoms. This is often seen as a benign flaw because problems of living and emotional suffering, even if not true disorders, may benefit from support and treatment. However, diagnosis of a disorder in our society has many ramifications not only for treatment choice but for broader social reactions to the diagnosed individual. In particular, mental disorders impose a sick role on individuals and place a burden upon them to change; thus, disorders decrease the level of respect and acceptance generally accorded to those with even annoying normal variations in traits and features. Thus, minimizing false positives is important to a pluralistic society. The harmful dysfunction analysis of disorder is used to diagnose the sources of likely false positives, and propose potential remedies to the current weaknesses in the validity of diagnostic criteria.
The Role of MDMA (Ecstasy) in Coping with Negative Life Situations Among Urban Young Adults
Moonzwe, Lwendo S.; Schensul, Jean J.; Kostick, Kristin M.
2011-01-01
This article examines the role of Ecstasy (MDMA or 3, 4-methylenedioxymethamphetamine) as a drug used for self-medication and coping with both short- and long-term negative life situations. We show that urban youth who do not have a specific diagnosed mental illness are more likely than those who have been diagnosed and have received treatment to use Ecstasy to cope with both situational stress and lifetime trauma. Diagnosed and treated youth sometimes self-medicate with other drugs, but do not choose Ecstasy for mediation of their psychological stress. We discuss the implications of self-medication with Ecstasy for mental health services to urban youth experiencing mental health disparities, and for the continued testing and prescription of MDMA for therapeutic use in controlled clinical settings. PMID:22111403
Bruijn, Merel M C; Hermans, Frederik J R; Vis, Jolande Y; Wilms, Femke F; Oudijk, Martijn A; Kwee, Anneke; Porath, Martina M; Oei, Guid; Scheepers, Hubertina C J; Spaanderman, Marc E A; Bloemenkamp, Kitty W M; Haak, Monique C; Bolte, Antoinette C; Vandenbussche, Frank P H A; Woiski, Mallory D; Bax, Caroline J; Cornette, Jérôme M J; Duvekot, Johannes J; Bijvank, Bas W A N I J; van Eyck, Jim; Franssen, Maureen T M; Sollie, Krystyna M; van der Post, Joris A M; Bossuyt, Patrick M M; Kok, Marjolein; Mol, Ben W J; van Baaren, Gert-Jan
2017-02-01
Objective We assessed the influence of external factors on false-positive, false-negative, and invalid fibronectin results in the prediction of spontaneous delivery within 7 days. Methods We studied symptomatic women between 24 and 34 weeks' gestational age. We performed uni- and multivariable logistic regression to estimate the effect of external factors (vaginal soap, digital examination, transvaginal sonography, sexual intercourse, vaginal bleeding) on the risk of false-positive, false-negative, and invalid results, using spontaneous delivery within 7 days as the outcome. Results Out of 708 women, 237 (33%) had a false-positive result; none of the factors showed a significant association. Vaginal bleeding increased the proportion of positive fetal fibronectin (fFN) results, but was significantly associated with a lower risk of false-positive test results (odds ratio [OR], 0.22; 95% confidence intervals [CI], 0.12-0.39). Ten women (1%) had a false-negative result. None of the investigated factors was significantly associated with a significantly higher risk of false-negative results. Twenty-one tests (3%) were invalid; only vaginal bleeding showed a significant association (OR, 4.5; 95% CI, 1.7-12). Conclusion The effect of external factors on the performance of qualitative fFN testing is limited, with vaginal bleeding as the only factor that reduces its validity. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
40 CFR 1045.110 - How must my engines diagnose malfunctions?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 32 2010-07-01 2010-07-01 false How must my engines diagnose malfunctions? 1045.110 Section 1045.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM SPARK-IGNITION PROPULSION MARINE ENGINES AND VESSELS...
40 CFR 1045.110 - How must my engines diagnose malfunctions?
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 34 2013-07-01 2013-07-01 false How must my engines diagnose malfunctions? 1045.110 Section 1045.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM SPARK-IGNITION PROPULSION MARINE ENGINES AND VESSELS...
40 CFR 1045.110 - How must my engines diagnose malfunctions?
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 33 2014-07-01 2014-07-01 false How must my engines diagnose malfunctions? 1045.110 Section 1045.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM SPARK-IGNITION PROPULSION MARINE ENGINES AND VESSELS...
40 CFR 1045.110 - How must my engines diagnose malfunctions?
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 34 2012-07-01 2012-07-01 false How must my engines diagnose malfunctions? 1045.110 Section 1045.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM SPARK-IGNITION PROPULSION MARINE ENGINES AND VESSELS...
40 CFR 1045.110 - How must my engines diagnose malfunctions?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 33 2011-07-01 2011-07-01 false How must my engines diagnose malfunctions? 1045.110 Section 1045.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM SPARK-IGNITION PROPULSION MARINE ENGINES AND VESSELS...
Saingam, Prakit; Li, Bo; Yan, Tao
2018-06-01
DNA-based molecular detection of microbial pathogens in complex environments is still plagued by sensitivity, specificity and robustness issues. We propose to address these issues by viewing them as inadvertent consequences of requiring specific and adequate amplification (SAA) of target DNA molecules by current PCR methods. Using the invA gene of Salmonella as the model system, we investigated if next generation sequencing (NGS) can be used to directly detect target sequences in false-negative PCR reaction (PCR-NGS) in order to remove the SAA requirement from PCR. False-negative PCR and qPCR reactions were first created using serial dilutions of laboratory-prepared Salmonella genomic DNA and then analyzed directly by NGS. Target invA sequences were detected in all false-negative PCR and qPCR reactions, which lowered the method detection limits near the theoretical minimum of single gene copy detection. The capability of the PCR-NGS approach in correcting false negativity was further tested and confirmed under more environmentally relevant conditions using Salmonella-spiked stream water and sediment samples. Finally, the PCR-NGS approach was applied to ten urban stream water samples and detected invA sequences in eight samples that would be otherwise deemed Salmonella negative. Analysis of the non-target sequences in the false-negative reactions helped to identify primer dime-like short sequences as the main cause of the false negativity. Together, the results demonstrated that the PCR-NGS approach can significantly improve method sensitivity, correct false-negative detections, and enable sequence-based analysis for failure diagnostics in complex environmental samples. Copyright © 2018 Elsevier B.V. All rights reserved.
Paterniti, Sabrina; Bisserbe, Jean-Claude
2018-05-29
Identifying bipolar patients in the first phases of the illness is essential to establish adequate treatment. The goal of this study was to examine the discriminant ability of the Mood Disorders Questionnaire (MDQ) in recognizing bipolar patients referred to a tertiary care structure. Between 2006 and 2012, we assessed 843 individuals referred to the Mood Disorders Program by family physicians in the community. The Structured Clinical Interview for DSM-IV-TR (SCID) was used to assess diagnoses. A nurse collected the information about lifetime symptoms of (hypo)mania in 759 individuals using the MDQ. Univariate chi-square test and logistic regression were used for the statistical analysis. Overall, 86% of the sample had a current anxiety or depressive disorder. When compared to the diagnoses formulated through the SCID, the sensitivity of the MDQ was 75.0%, the specificity was 74%, the positive predictive value was 55%, and the negative predictive value was 88%. Among non-bipolar patients, current post-traumatic stress disorder, borderline personality disorder, current or early remission substance use disorder, and the history of childhood abuse were independently associated with false positive screening using the MDQ. Individuals with current substance use disorders were under-represented, whether or not the patients were aware of their diagnosis of bipolar disorder was not recorded, and the history of childhood abuse was collected based on an open interview. The self-rated measure of the symptoms listed by the MDQ seems to measure a dimension shared by both bipolar disorder and other conditions characterized by affective instability and impulsivity. Copyright © 2018 Elsevier B.V. All rights reserved.
Recombinant allergen-based IgE testing to distinguish bee and wasp allergy.
Mittermann, Irene; Zidarn, Mihaela; Silar, Mira; Markovic-Housley, Zora; Aberer, Werner; Korosec, Peter; Kosnik, Mitja; Valenta, Rudolf
2010-06-01
The identification of the disease-causing insect in venom allergy is often difficult. To establish recombinant allergen-based IgE tests to diagnose bee and yellow jacket wasp allergy. Sera from patients with bee and/or wasp allergy (n = 43) and patients with pollen allergy with false-positive IgE serology to venom extracts were tested for IgE reactivity in allergen extract-based tests or with purified allergens, including nonglycosylated Escherichia coli-expressed recombinant (r) Api m 1, rApi m 2, rVes v 5, and insect cell-expressed, glycosylated rApi m 2 as well as 2 natural plant glycoproteins (Phl p 4, bromelain). The patients with venom allergy could be diagnosed with a combination of E coli-expressed rApi m 1, rApi m 2, and rVes v 5 whereas patients with pollen allergy remained negative. For a group of 29 patients for whom the sensitizing venom could not be identified with natural allergen extracts, testing with nonglycosylated allergens allowed identification of the sensitizing venom. Recombinant nonglycosylated allergens also allowed definition of the sensitizing venom for those 14 patients who had reacted either with bee or wasp venom extracts. By IgE inhibition studies, it is shown that glycosylated Api m 2 contains carbohydrate epitopes that cross-react with natural Api m 1, Ves v 2, natural Phl p 4, and bromelain, thus identifying cross-reactive structures responsible for serologic false-positive test results or double-positivity to bee and wasp extracts. Nonglycosylated recombinant bee and wasp venom allergens allow the identification of patients with bee and wasp allergy and should facilitate accurate prescription of venom immunotherapy. Copyright (c) 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.
Pichler, Renate; Tulchiner, Gennadi; Oberaigner, Wilhelm; Schaefer, Georg; Horninger, Wolfgang; Brunner, Andrea; Heidegger, Isabel
2017-10-01
We evaluated the diagnostic accuracy of urinary cytology (UCy) for detecting recurrence in the remnant urothelium (RRU) after radical cystectomy (RC) for urothelial cancer. We conducted a 10-year retrospective analysis of a prospectively collected, single-center RC database comprising 177 patients who had undergone follow-up examinations at our department with ≥ 1 available postoperative UCy specimen. UCy specimens were classified using the Papanicolaou scheme. In total, 957 cytology specimens were collected. Negative UCy results were noted in 927 (96.8%), atypical urothelial cells in 19 (2.0%), and suspicious/positive for malignancy in 11 (1.2%) cases. RRU was diagnosed in 16 patients (9.1%) during a mean follow-up period of 37 months (range, 1-118 months). The mean interval from RC to RRU was 34.7 months. Only 2 of 11 positive UCy specimens (18.2%) were falsely positive, for an overall sensitivity and specificity of 56.3% and 98.8% for predicting RRU, respectively. Urethral recurrence was diagnosed by UCy alone before the patients had developed symptoms in 8 of 12 cases (66.7%). Patients with clinical symptoms at the diagnosis of RRU had poorer cancer-specific survival rates than those of asymptomatic patients, although this trend was not statistically significant (P = .496). Moreover, positive UCy findings were associated with significantly lower overall survival (P < .001) and cancer-specific survival (P = .04) compared with negative UCy findings. Our results underline the predictive value of UCy in the surveillance of the remnant urothelium, with early detection of urethral recurrence before the development of clinical symptoms. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.
Accuracy of FDG-PET to diagnose lung cancer in a region of endemic granulomatous disease.
Deppen, Stephen; Putnam, Joe B; Andrade, Gabriela; Speroff, Theodore; Nesbitt, Jonathan C; Lambright, Eric S; Massion, Pierre P; Walker, Ron; Grogan, Eric L
2011-08-01
The 18 F-fluorodeoxyglucose-positron emission tomography (FDG-PET) is used to evaluate suspicious pulmonary lesions due to its diagnostic accuracy. The southeastern United States has a high prevalence of infectious granulomatous lung disease, and the accuracy of FDG-PET may be reduced in this population. We examined the diagnostic accuracy of FDG-PET in patients with known or suspected non-small cell lung cancer treated at our institution. A total of 279 patients, identified through our prospective database, underwent an operation for known or suspected lung cancer. Preoperative FDG-PET in 211 eligible patients was defined by standardized uptake value greater than 2.5 or by description ("moderate" or "intense") as avid. Sensitivity, specificity, positive and negative predictive values, likelihood ratios, and decision diagrams were calculated for FDG-PET in all patients and in patients with indeterminate nodules. In all eligible patients (n=211), sensitivity and specificity of FDG-PET were 92% and 40%, respectively. Positive and negative predictive values were 86% and 55%. Overall FDG-PET accuracy to diagnose lung cancer was 81%. Preoperative positive likelihood ratio for FDG-PET diagnosis of lung cancer in this population was 1.5 compared with previously published values of 7.1. In 113 indeterminate lesions, 65% had lung cancer and the sensitivity and specificity were 89% and 40%, respectively. Twenty-four benign nodules (60%) had false positive FDG-PET scans. Twenty-two of 43 benign nodules (51%) were granulomas. In a region with endemic granulomatous diseases, the specificity of FDG-PET for diagnosis of lung cancer was 40%. Clinical decisions and future clinical predictive models for lung cancer must accommodate regional variation of FDG-PET scan results. Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
The role of fear in diagnosing cancer in time.
Machácek, J
1996-01-01
The causes of the relatively frequent late discovery of the breast cancer (40-60%) in Czech republic are numerous. One of them is the attitude of the patient herself to the disease. Fear and anxiety play are important role in seeing her doctor too late. Beliefs feelings and attitudes to treatment have been formed in potential patients mostly by negative experience and information. It is necessary to impress to the female population the idea that breast cancer can be curable and that the degree of successful treatment depends on early diagnosis and that fear and anxiety delaying the therapy are dangerous. The sources of fear are as follows: false image of incurable disease an idea of subsequent loss of an organs--the symbols of womanhood and sex-appeal physical and psychical degradation subsequent fears of losing a partner loss of social prestige and position at work considerable change in hitherto lifestyle. Own knowledge that these negative ideas are not quite true must be accepted not only by these who have been treated but first of all by those who could find themselves in such a difficult situation. Many other potential sources of fear and worries concern health care. Apart from the lack of interest reluctance and rudeness of hospital staff it is a chronic shortcoming of positive information and intensive health education. In authors group of 120 patients has been proved that mental feelings, fear and anxiety significantly influence the timeliness of diagnosing an illness and its whole course. It is the physicians foremost task to look for any possible ways of overcoming the sources of fear and anxiety and thus to help women to see a doctor as soon as possible. It would be a significant contribution to decreasing the number of advanced stages of breast cancer.
Napoleon, B; Alvarez-Sanchez, M V; Gincoul, R; Pujol, B; Lefort, C; Lepilliez, V; Labadie, M; Souquet, J C; Queneau, P E; Scoazec, J Y; Chayvialle, J A; Ponchon, T
2010-07-01
Distinguishing pancreatic adenocarcinoma from other pancreatic masses remains challenging with current imaging techniques. This prospective study aimed to evaluate the accuracy of a new procedure, imaging the microcirculation pattern of the pancreas by contrast-enhanced harmonic endoscopic ultrasound (CEH-EUS) with a new Olympus prototype echo endoscope. 35 patients presenting with solid pancreatic lesions were prospectively enrolled. All patients had conventional B mode and power Doppler EUS. After an intravenous bolus injection of 2.4 ml of a second-generation ultrasound contrast agent (SonoVue) CEH-EUS was then performed with a new Olympus prototype echo endoscope (xGF-UCT 180). The microvascular pattern was compared with the final diagnosis based on the pathological examination of specimens from surgery or EUS-guided fine-needle aspiration (EUS-FNA) or on follow-up for at least 12 months. The final diagnoses were: 18 adenocarcinomas, 9 neuroendocrine tumors, 7 chronic pancreatitis, and 1 stromal tumor. Power Doppler failed to display microcirculation, whereas harmonic imaging demonstrated it in all cases. Out of 18 lesions with a hypointense signal on CEH-EUS, 16 were adenocarcinomas. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy of hypointensity for diagnosing pancreatic adenocarcinoma were 89 %, 88 %, 88 %, 89 %, and 88.5 %, compared with corresponding values of 72 %, 100 %, 77 %, 100 %, and 86 % for EUS-FNA. Of five adenocarcinomas with false-negative results at EUS-FNA, four had a hypointense echo signal at CEH-EUS. CEH-EUS with the new Olympus prototype device successfully visualizes the microvascular pattern in pancreatic solid lesions, and may be useful for distinguishing adenocarcinomas from other pancreatic masses.
Felten, Sandra; Leutenegger, Christian M; Balzer, Hans-Joerg; Pantchev, Nikola; Matiasek, Kaspar; Wess, Gerhard; Egberink, Herman; Hartmann, Katrin
2017-08-02
Feline coronavirus (FCoV) exists as two pathotypes, and FCoV spike gene mutations are considered responsible for the pathotypic switch in feline infectious peritonitis (FIP) pathogenesis. The aim of this study was to evaluate sensitivity and specificity of a real-time reverse transcriptase polymerase chain reaction (RT-PCR) specifically designed to detect FCoV spike gene mutations at two nucleotide positions. It was hypothesized that this test would correctly discriminate feline infectious peritonitis virus (FIPV) and feline enteric coronavirus (FECV). The study included 63 cats with signs consistent with FIP. FIP was confirmed in 38 cats. Twenty-five control cats were definitively diagnosed with a disease other than FIP. Effusion and/or serum/plasma samples were examined by real-time RT-PCR targeting the two FCoV spike gene fusion peptide mutations M1058 L and S1060A using an allelic discrimination approach. Sensitivity, specificity, negative and positive predictive values including 95% confidence intervals (95% CI) were calculated. FIPV was detected in the effusion of 25/59 cats, one of them being a control cat with chronic kidney disease. A mixed population of FIPV/FECV was detected in the effusion of 2/59 cats; all of them had FIP. RT-PCR was negative or the pathotype could not be determined in 34/59 effusion samples. In effusion, sensitivity was 68.6% (95% CI 50.7-83.2), specificity was 95.8% (95% CI 78.9-99.9). No serum/plasma samples were positive for FIPV. Although specificity of the test in effusions was high, one false positive result occurred. The use of serum/plasma cannot be recommended due to a low viral load in blood.
Mucinous cystadenocarcinoma of the breast: the challenge of diagnosing a rare entity
Koufopoulos, Nektarios; Goudeli, Christina; Syrios, John; Filopoulos, Evangelos; Khaldi, Lubna
2017-01-01
Mucinous cystadenocarcinoma is an extremely rare variant of primary breast tumor which is histologically similar to mucinous cystadenocarcinoma of the ovary and pancreas. Herein we report a case of a 63 years old woman diagnosed with diverse histological types of non-synchronous rare primary breast tumors, a medullary carcinoma of the right breast and a mucinous cystadenocarcinoma of the left breast. Macroscopically the neoplasm appeared multilocular filled with mucoid material. Under light microscopy the cystic areas were lined by columnar cells with abundant intracellular and extracellular mucin. Solid areas were composed of tall columnar cells with intracellular mucin. Moderate to marked atypia was noticed and tumor cells stained positive for cytokeratin 7 and negative for cytokeratin 20. Moreover tumor cells displayed a basal like immunophenotype expressed as followed: ER negative, PR negative, HER-2 negative, cytokeratin (CK5/6) positive and EGFR positive. PMID:29081926
Mucinous cystadenocarcinoma of the breast: the challenge of diagnosing a rare entity.
Koufopoulos, Nektarios; Goudeli, Christina; Syrios, John; Filopoulos, Evangelos; Khaldi, Lubna
2017-10-03
Mucinous cystadenocarcinoma is an extremely rare variant of primary breast tumor which is histologically similar to mucinous cystadenocarcinoma of the ovary and pancreas. Herein we report a case of a 63 years old woman diagnosed with diverse histological types of non-synchronous rare primary breast tumors, a medullary carcinoma of the right breast and a mucinous cystadenocarcinoma of the left breast. Macroscopically the neoplasm appeared multilocular filled with mucoid material. Under light microscopy the cystic areas were lined by columnar cells with abundant intracellular and extracellular mucin. Solid areas were composed of tall columnar cells with intracellular mucin. Moderate to marked atypia was noticed and tumor cells stained positive for cytokeratin 7 and negative for cytokeratin 20. Moreover tumor cells displayed a basal like immunophenotype expressed as followed: ER negative, PR negative, HER-2 negative, cytokeratin (CK5/6) positive and EGFR positive.
Kommoss, F; Lax, S F
2016-11-01
Making an incorrect histopathological diagnosis of an endometrial lesion may lead to unwanted loss of fertility and therapy-associated morbidity; therefore, endometrial carcinomas need to be correctly typed and differentiated from hyperplastic precursors, benign lesions and artifacts. Typical diagnostic pitfalls are described in this article. Misdiagnosing endometrial lesions can be avoided by paying thorough attention to gross as well as microscopic features and by taking crucial differential diagnoses into consideration. These are, in particular, well-differentiated endometrioid adenocarcinoma of the endometrium versus atypical endometrial hyperplasia, myoinvasive endometrioid adenocarcinoma versus atypical polypoid adenomyoma and endometrioid carcinoma versus serous carcinoma of the endometrium with a predominantly glandular pattern. It is also important to consider the possibility of a false positive diagnosis of atypical endometrial hyperplasia or carcinoma in cases of biopsy-induced artifacts.
Whiteley, M S; Dos Santos, S J; Harrison, C C; Holdstock, J M; Lopez, A J
2015-12-01
To assess the suitability of transvaginal duplex ultrasonography to identify pathological reflux in the ovarian and internal iliac veins in women. A retrospective study of patients treated in 2011 and 2012 was performed in a specialised vein clinic. Diagnostic transvaginal duplex ultrasonography in women presenting with symptoms or signs of pelvic vein reflux were compared with the outcomes of treatment from pelvic vein embolisation. A repeat transvaginal duplex ultrasonography was performed 6 weeks later by a blinded observer and any residual reflux was identified. Results from 100 sequential patients were analysed. Mean age 44.2 years (32-69) with mode average parity of 3 (0-5 deliveries). Pre-treatment, 289/400 veins were refluxing (ovarian - 29 right, 81 left; internal iliac - 93 right, 86 left). Coil embolisation was successful in 86/100 patients and failed partially in 14/100 - 5 due to failure to cannulate the target vein. One false-positive diagnosis was made. Currently there is no accepted gold standard for pelvic vein incompetence. Comparing transvaginal duplex ultrasonography with the outcome from selectively treating the veins identified as having pathological reflux with coil embolisation, there were no false-negative diagnoses and only one false-positive. This study suggests that transvaginal duplex ultrasonography could be the gold standard in assessing pelvic vein reflux. © The Author(s) 2014.
[Roaming through methodology. XXXII. False test results].
van der Weijden, T; van den Akker, M
2001-05-12
The number of requests for diagnostic tests is rising. This leads to a higher chance of false test results. The false-negative proportion of a test is the proportion of negative test results among the diseased subjects. The false-positive proportion is the proportion of positive test results among the healthy subjects. The calculation of the false-positive proportion is often incorrect. For example, instead of 1 minus the specificity it is calculated as 1 minus the positive predictive value. This can lead to incorrect decision-making with respect to the application of the test. Physicians must apply diagnostic tests in such a way that the risk of false test results is minimal. The patient should be aware that a perfectly conclusive diagnostic test is rare in medical practice, and should more often be informed of the implications of false-positive and false-negative test results.
Shtessel, Maria; Lobell, Elizabeth; Hudes, Golda; Rosenstreich, David; de Vos, Gabriele
2017-01-01
Background: Allergists commonly perform intradermal skin testing (IDST) after negative skin-prick testing (SPT) to comprehensively diagnose environmental allergic sensitization. However, with the availability of modern methods to detect serum-specific immunoglobulin E (ssIgE), it is unclear if ssIgE testing could substitute for IDST. Objective: To determine the efficacy of ssIgE testing and IDST when added to SPT in diagnosing environmental allergic sensitizations. Methods: SPT, IDST, and ssIgE testing to nine common environmental allergens were analyzed in 75 patients with oculonasal symptoms who presented to our allergy clinics in the Bronx, New York, between January 2014 and May 2015. Results: A total of 651 SPT and 499 ssIgE tests were independently performed and revealed 162 (25%) and 127 (25%) sensitizations, respectively. When SPT results were negative, IDST results revealed 108 of 452 additional sensitizations (24%). In contrast, when SPT results were negative, ssIgE test results only revealed 9% additional sensitizations. When both SPT and IDST results were negative, ssIgE testing only detected 3% of additional sensitizations, and ssIgE levels were typically low in these cases (median, 1.25 kU/L; range, 0.357–4.47 kU/L). When both SPT and ssIgE test results were negative, IDST results detected 15% additional sensitizations. Conclusion: IDST detected more additional environmental sensitizations compared with ssIgE testing. IDST, therefore, may be useful when the SPT and/or ssIgE testing results were negative, but the exposure history indicated relevant allergic sensitization. Serology added only a little more information if both SPT and IDST results were negative but may be useful in combination with SPT if IDST cannot be performed. PMID:28583228
Ferastraoaru, Denisa; Shtessel, Maria; Lobell, Elizabeth; Hudes, Golda; Rosenstreich, David; de Vos, Gabriele
2017-06-01
Allergists commonly perform intradermal skin testing (IDST) after negative skin-prick testing (SPT) to comprehensively diagnose environmental allergic sensitization. However, with the availability of modern methods to detect serum-specific immunoglobulin E (ssIgE), it is unclear if ssIgE testing could substitute for IDST. To determine the efficacy of ssIgE testing and IDST when added to SPT in diagnosing environmental allergic sensitizations. SPT, IDST, and ssIgE testing to nine common environmental allergens were analyzed in 75 patients with oculonasal symptoms who presented to our allergy clinics in the Bronx, New York, between January 2014 and May 2015. A total of 651 SPT and 499 ssIgE tests were independently performed and revealed 162 (25%) and 127 (25%) sensitizations, respectively. When SPT results were negative, IDST results revealed 108 of 452 additional sensitizations (24%). In contrast, when SPT results were negative, ssIgE test results only revealed 9% additional sensitizations. When both SPT and IDST results were negative, ssIgE testing only detected 3% of additional sensitizations, and ssIgE levels were typically low in these cases (median, 1.25 kU/L; range, 0.357-4.47 kU/L). When both SPT and ssIgE test results were negative, IDST results detected 15% additional sensitizations. IDST detected more additional environmental sensitizations compared with ssIgE testing. IDST, therefore, may be useful when the SPT and/or ssIgE testing results were negative, but the exposure history indicated relevant allergic sensitization. Serology added only a little more information if both SPT and IDST results were negative but may be useful in combination with SPT if IDST cannot be performed.
Dong, YiJie; Mao, MinJing; Zhan, WeiWei; Zhou, JianQiao; Zhou, Wei; Yao, JieJie; Hu, YunYun; Wang, Yan; Ye, TingJun
2018-06-01
Our goal was to assess the diagnostic efficacy of ultrasound (US)-guided fine-needle aspiration (FNA) of thyroid nodules according to size and US features. A retrospective correlation was made with 1745 whole thyroidectomy and hemithyroidectomy specimens with preoperative US-guided FNA results. All cases were divided into 5 groups according to nodule size (≤5, 5.1-10, 10.1-15, 15.1-20, and >20 mm). For target nodules, static images and cine clips of conventional US and color Doppler were obtained. Ultrasound images were reviewed and evaluated by two radiologists with at least 5 years US working experience without knowing the results of pathology, and then agreement was achieved. The Bethesda category I rate was higher in nodules larger than 15 mm (P < .05). The diagnostic accuracy was best in nodules of 5 to 10 mm in diameter. The sensitivity, accuracy, PPV, and LR for negative US-guided FNA results were better in nodules with a size range of 5 to 15 mm. The specificity, negative predictive value (NPV), and LR for positive results and the Youden index rose with increasing nodule size. Seventeen false-positive and 60 false-negative results were found in this study. The false-negative rate rose with increasing nodule size. However, the false-positive rate was highest in the group containing the smallest nodules. Nodules with circumscribed margins and those that were nonsolid and nonhypoechoic and had no microcalcifications correlated with Bethesda I FNA results. Nodules with circumscribed margins and those that were nonsolid, heterogeneous, and nonhypoechoic and had increased vascularity correlated with false-negative FNA results. Borders correlated with Bethesda I false-negative and false-positive FNA results. Tiny nodules (≤5 mm) with obscure borders tended to yield false-positive FNA results. Large nodules (>20 mm) with several US features tended to yield false-negative FNA results. © 2017 by the American Institute of Ultrasound in Medicine.
Manatsathit, Wuttiporn; Khrucharoen, Usah; Jensen, Dennis M.; Hines, O. Joe; Kovacs, Thomas; Ohning, Gordon; Jutabha, Rome; Ghassemi, Kevin; Dulai, Gareth S.; Machicado, Gustavo
2017-01-01
Background To evaluate roles of intraoperative endoscopy (IOE) in management of severe obscure GI bleeding (OGIB) before vs. after introduction of video capsule endoscopy (VCE) and deep enteroscopy (DE). Methods We retrospectively reviewed prospectively collected data of patients undergoing IOE for severe OGIB in a tertiary referral center. Results 52 patients had laparotomy/IOE for OGIB, 11 pre and 41 post VCE/DE eras. In the pre VCE/DE era, 36.4% (4/11) had preoperative presumptive diagnoses while in the post VCE/DE era presumptive diagnoses were made in 48.8% (20/41) (p= 0.18). Preoperative evaluation led to correct diagnoses in 18.2% (2/11) in the pre and 51.2% (21/41) in the post VCE/DE era (p=0.09). Vascular lesions and ulcers were the most common diagnoses, but rebleeding was common. No rebleeding was found among patients with tumors, Meckel's diverticulum, and aortoenteric fistula. Conclusions Presumptive diagnoses in the post VCE/DE era were usually accurate. If VCE or DE are negative, the probability of negative IOE is high. Patients with tumors and Meckel's diverticulum were the best candidates for IOE. PMID:28629608
Arjona, Alvaro; Barquero, Nuria; Doménech, Ana; Tejerizo, German; Collado, Victorio M; Toural, Cristina; Martín, Daniel; Gomez-Lucia, Esperanza
2007-02-01
Laboratory diagnosis of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) usually involves both viruses, as the clinical signs are similar and coinfection may occur. Serological methods may not represent an accurate diagnosis: maternal antibodies or cross-reactions may give false positive results to FIV, and false negative results may occur in latent FeLV status, or in certain FIV infection stages. A nested polymerase chain reaction (PCR) technique was designed to detect FeLV, FIV and feline endogenous retrovirus simultaneously. The detection of endogenous sequences was considered indicative of successful DNA extraction. The technique was used to diagnose FIV and FeLV in the blood cells of 179 cats. The kappa value with the serological data was 0.69 for FeLV and 0.87 for FIV. The joint detection of FeLV and FIV by this novel nested PCR is sensitive, specific, fast and convenient, and its applicability for clinical diagnosis is promising, as the direct evidence of the presence of the virus is more realistic than the indirect data provided by the serological detection.
Mačkić-Đurović, Mirela; Projić, Petar; Ibrulj, Slavka; Cakar, Jasmina; Marjanović, Damir
2014-05-01
The goal of this study was to examine the effectiveness of 6 STR markers application (D21S1435, D21S11, D21S1270, D21S1411, D21S226 and IFNAR) in molecular genetic diagnostics of Down syndrome (DS) and to compare it with cytogenetic method. Testing was performed on 73 children, with the previously cytogenetically confirmed Down syndrome. DNA isolated from the buccal swab was used. Previously mentioned loci located on chromosome 21 were simultaneously amplified using quantitative fluorescence PCR (QF PCR). Using this method, 60 previously cytogenetically diagnosed DS with standard type of trisomy 21 were confirmed. Furthermore, six of eight children with mosaic type of DS were detected. Two false negative results for mosaic type of DS were obtained. Finally, five children with the translocation type of Down syndrome were also confirmed with this molecular test. In conclusion, molecular genetic analysis of STR loci is fast, cheap and simple method that could be used in detection of DS. Regarding possible false results detected for certain number of mosaic types, cytogenetic analysis should be used as a confirmatory test.
Cosnes-Lambe, Cecile; Raymond, Josette; Vallet, Christelle; Armengaud, Jean-Baptiste; Bosdure, Emmanuelle; Catalano-Pons, Charlotte; Chalumeau, Martin; El Hajje, Marie-Joelle; Moulin, Florence; de Suremain, Nathalie; Reglier-Poupet, Hélène; Poyart, Claire; Gendrel, Dominique
2008-10-01
False-negative findings of polymerase chain reaction (PCR) for genuine pertussis as well as the numerous atypical forms of whooping cough make it difficult to diagnose this disease in young babies. For two years, real-time PCR was performed to test for Bordetella pertussis in 86 infants younger than 6 months hospitalized for apnea or paroxysmal and/or vomiting cough and in 205 of their household contacts, whether or not they coughed. Group 1 included 30 infants for whom PCR detected B. pertussis (25 of whom were also RSV+). PCR was also positive for at least one household contact in 25/30 families. This group included 16 babies with apnea and 12 who developed a whooping cough during follow-up. Group 2 comprised 12 infants whose PCR was negative while at least one household contact had positive results. Five of these infants had severe apnea and 6 developed a whooping cough. Group 3 included 44 infants (28 RSV +) for whom PCR was negative in the index case and in the household contacts: none developed a whooping cough during follow-up. Only 3 of the 54 positive household contacts had a paroxysmal cough or a typical whooping cough and 12 had no cough at all. Positive PCR in a household contact, symptomatic or not, is helpful for the diagnosis of atypical whooping cough in young infants.
Serological diagnosis of bovine brucellosis using B. melitensis strain B115.
Corrente, Marialaura; Desario, Costantina; Parisi, Antonio; Grandolfo, Erika; Scaltrito, Domenico; Vesco, Gesualdo; Colao, Valeriana; Buonavoglia, Domenico
2015-12-01
Bovine brucellosis is diagnosed by official tests, such as Rose Bengal plate test (RBPT) and Complement Fixation test (CFT). Both tests detect antibodies directed against the lipolysaccharide (LPS) of Brucella cell wall. Despite their good sensitivity, those tests do not discriminate between true positive and false positive serological reactions (FPSR), the latter being generated by animals infected with other Gram negative microorganisms that share components of Brucella LPS. In this study, an antigenic extract from whole Brucella melitensis B115 strain was used to set up an ELISA assay for the serological diagnosis of bovine brucellosis. A total of 148 serum samples from five different groups of animals were tested: Group A: 28 samples from two calves experimentally infected with Yersinia enterocolitica O:9; Group B: 30 samples from bovines infected with Brucella abortus; Group C: 50 samples from brucellosis-free herds; Group D: 20 samples RBPT positive and CFT negative; Group E: 20 samples both RBPT and CFT positive. Group D and Group E serum samples were from brucellosis-free herds. Positive reactions were detected only by RBPT and CFT in calves immunized with Y. enterocolitica O:9. Sera from Group B animals tested positive also in the ELISA assay, whereas sera from the remaining groups were all negative. The results obtained encourage the use of the ELISA assay to implement the serological diagnosis of brucellosis. Copyright © 2015 Elsevier B.V. All rights reserved.
Plipat, Tanarak; Buathong, Rome; Wacharapluesadee, Supaporn; Siriarayapon, Potjaman; Pittayawonganon, Chakrarat; Sangsajja, Chariya; Kaewpom, Thongchai; Petcharat, Sininat; Ponpinit, Teerada; Jumpasri, Jaruphan; Joyjinda, Yutthana; Rodpan, Apaporn; Ghai, Siriporn; Jittmittraphap, Akanitt; Khongwichit, Sarawut; Smith, Duncan R; Corman, Victor M; Drosten, Christian; Hemachudha, Thiravat
2017-08-17
Thailand reported the first Middle East respiratory syndrome (MERS) case on 18 June 2015 (day 4) in an Omani patient with heart condition who was diagnosed with pneumonia on hospital admission on 15 June 2015 (day 1). Two false negative RT-PCR on upper respiratory tract samples on days 2 and 3 led to a 48-hour diagnosis delay and a decision to transfer the patient out of the negative pressure unit (NPU). Subsequent examination of sputum later on day 3 confirmed MERS coronavirus (MERS-CoV) infection. The patient was immediately moved back into the NPU and then transferred to Bamrasnaradura Infectious Disease Institute. Over 170 contacts were traced; 48 were quarantined and 122 self-monitored for symptoms. High-risk close contacts exhibiting no symptoms, and whose laboratory testing on the 12th day after exposure was negative, were released on the 14th day. The Omani Ministry of Health (MOH) was immediately notified using the International Health Regulation (IHR) mechanism. Outbreak investigation was conducted in Oman, and was both published on the World Health Organization (WHO) intranet and shared with Thailand's IHR focal point. The key to successful infection control, with no secondary transmission, were the collaborative efforts among hospitals, laboratories and MOHs of both countries. This article is copyright of The Authors, 2017.
Diagnosing erectile dysfunction: the penile dynamic colour duplex ultrasound revisited.
Aversa, A; Bruzziches, R; Spera, G
2005-12-01
A number of disease processes of the penis including Peyronie's disease, priapism, penile fractures and tumors are clearly visualized with ultrasound. Diagnostic evaluation of erectile dysfunction (ED) by penile dynamic colour-duplex Doppler ultrasonography (D-CDDU) is actually considered a second level approach to ED patients because of the fact that intracavernous injections test IV with prostaglandin-E(1) may provide important information about the patients' erectile capacity. However, no direct vascular imaging and a high percentage of false negative diagnoses of vasculogenic ED are its major pitfalls and subsequent treatment decisions remain quite limited. The occurrence of ED and its sentinel relationship to cardiovascular disease has prompted more accurate vascular screening in all patients even in the absence of cardiovascular risk factors. The sonographic evaluation of the intima-media thickness of the carotid arteries may sometimes represent an early manifestation of diffuse atherosclerotic disease and endothelial damage. This latter finding is often the cause of failure to oral agents, i.e. phosphodiesterase inhibitors, because of inability of the dysfunctional endothelium to release nitric oxide. D-CDDU represents an accurate tool to investigate cavernous artery inflow and venous leakage when compared with more invasive diagnostic techniques i.e. selective arteriography and dynamic infusion cavernosometry along with cavernosography.
Computed tomographic imaging in the pediatric patient with a seatbelt sign: still not good enough.
Kopelman, Tammy R; Jamshidi, Ramin; Pieri, Paola G; Davis, Karole; Bogert, James; Vail, Sydney J; Gridley, Daniel; Singer Pressman, Melissa A
2018-02-01
Considering the improvements in CT over the past decade, this study aimed to determine whether CT can diagnose HVI in pediatric trauma patients with seatbelt signs (SBS). We retrospectively identified pediatric patients with SBS who had abdominopelvic CT performed on initial evaluation over 5 1/2years. Abnormal CT was defined by identification of any intra-abdominal abnormality possibly related to trauma. One hundred twenty patients met inclusion criteria. CT was abnormal in 38/120 (32%) patients: 34 scans had evidence of HVI and 6 showed solid organ injury (SOI). Of the 34 with suspicion for HVI, 15 (44%) had small amounts of isolated pelvic free fluid as the only abnormal CT finding; none required intervention. Ultimately, 16/120 (13%) patients suffered HVI and underwent celiotomy. Three patients initially had a normal CT but required celiotomy for clinical deterioration within 20h of presentation. False negative CT rate was 3.6%. The sensitivity, specificity and accuracy of CT to diagnose significant HVI in the presence of SBS were 81%, 80%, and 80%, respectively. Despite improvements in CT, pediatric patients with SBS may have HVI not evident on initial CT confirming the need to observation for delayed manifestation of HVI. Level II Study of a Diagnostic Test. Copyright © 2017 Elsevier Inc. All rights reserved.
Diagnosis of intrauterine growth restriction: comparison of ultrasound parameters.
Ott, William J
2002-04-01
The objective of this study is an attempt to evaluate the best ultrasonic method of diagnosing intrauterine growth restriction (IUGR); a retrospective study of patients with singleton pregnancies who had been scanned at the author's institution within 2 weeks of their delivery was undertaken. Estimated fetal weight, abdominal circumference, head circumference/abdominal circumference ratio, abdominal circumference/femur length ratio, and umbilical artery S/D ratio were compared for accuracy in prediction IUGR in the neonate using both univariant and multivariant statistical analysis. Five hundred one (501) patients were analyzed. One hundred fourteen (114) neonates were classified as IUGR (22.8%). Doppler evaluation of the umbilical artery showed the best sensitivity while both abdominal circumference alone and estimated fetal weight showed similar specificity, positive and negative predictive value, and lowest false-positive and -negative results. Logistic regression analysis confirmed the univariant results and showed that, when used in combination, abdominal circumference and Doppler, or estimated fetal weight and Doppler resulted in the best predictive values. Either estimated fetal weight or abdominal circumference (alone) are accurate predictors of IUGR. Combined with Doppler studies of the umbilical artery either method will provide accurate evaluation of suspected IUGR.
Heterophile antibody interference in qualitative urine/serum hCG devices: Case report.
Patel, Khushbu K; Gronowski, Ann M
2016-06-01
This case report investigates the origin of a false positive result on a serum qualitative human chorionic gonadotropin (hCG) device. A 46-year-old woman diagnosed with chronic myeloid leukemia presented with nausea and vomiting. A qualitative serum hCG test was interpreted as positive; however, a quantitative serum hCG test was negative (<5IU/L). To further investigate this discrepancy, the sample was pretreated with heterophilic blocking reagent (HBR). Additionally, the sample was tested on other qualitative hCG devices composed of antibodies from different animal sources. Blocking reagent from an automated quantitative immunoassay was also tested for its ability to inhibit the heterophile antibody interference. The qualitative test result was negative after pretreatment with heterophilic blocking reagent. Other devices composed of antibodies from different animal sources also demonstrated mixed results with the patient's sample. Blocking reagent obtained from the automated quantitative assay inhibited the heterophile antibody interference in the patient's sample. This case demonstrates that positive serum point-of-care hCG results should be interpreted with caution and confirmed with a quantitative serum hCG immunoassay when clinical suspicion is raised. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
Redmond, C E; Healy, G M; Murphy, C F; O'Doherty, A; Foster, A
2017-02-01
Breast cancer in women under 40 years of age is rare and typically presents symptomatically. The optimal imaging modality for this patient group is controversial. Most women undergo ultrasonography with/without mammography. Young women typically have dense breasts, which can obscure the features of malignancy on film mammography, however, initial studies have suggested that digital mammography may have a more accurate diagnostic performance in younger women. Ultrasound generally performs well in this age group, although it is poor at detecting carcinoma in situ (DCIS). To evaluate the comparative diagnostic performance of ultrasonography and digital mammography in the initial diagnostic evaluation of women under 40 years of age with symptomatic breast cancer. Retrospective review of all women under the age of 40 years managed at our symptomatic breast cancer unit from January 2009 to December 2015. There were 120 patients that met the inclusion criteria for this study. The sensitivity of ultrasonography and digital mammography for breast cancer in this patient group was 95.8 and 87.5 %, respectively. The patients with a false negative mammographic examination were more likely to have dense breasts (p < 0.01). Five patients had a false negative ultrasonographic examination, withal of whom were diagnosed with DCIS detected by mammography. This study demonstrates the superior sensitivity of ultrasound for breast cancer in women under the age of 40 years, however, the results show that digital mammography has an important complimentary role in the comprehensive assessment of these patients, particularly in the diagnosis of DCIS.
Value of a Single-Tube Widal Test in Diagnosis of Typhoid Fever in Vietnam
Parry, Christopher M.; Hoa, Nguyen Thi Tuyet; Diep, To Song; Wain, John; Chinh, Nguyen Tran; Vinh, Ha; Hien, Tran Tinh; White, Nicholas J.; Farrar, Jeremy J.
1999-01-01
The diagnostic value of an acute-phase single-tube Widal test for suspected typhoid fever was evaluated with 2,000 Vietnamese patients admitted to an infectious disease referral hospital between 1993 and 1998. Test patients had suspected typhoid fever and a blood culture positive for Salmonella typhi (n= 1,400) or Salmonella paratyphi A (n = 45). Control patients had a febrile illness for which another cause was confirmed (malaria [n = 103], dengue [n = 76], or bacteremia due to another microorganism [n = 156] or tetanus (n = 265). An O-agglutinin titer of ≥100 was found in 18% of the febrile controls and 7% of the tetanus patients. Corresponding values for H agglutinins were 8 and 1%, respectively. The O-agglutinin titer was ≥100 in 83% of the blood culture-positive typhoid fever cases, and the H-agglutinin titer was ≥100 in 67%. The disease prevalence in investigated patients in this hospital was 30.8% (95% confidence interval, 26.8 to 35.1%); at this prevalence, an elevated level of H agglutinins gave better positive predictive values for typhoid fever than did O agglutinins. With a cutoff titer of ≥200 for O agglutinin or ≥100 for H agglutinin, the Widal test would diagnose correctly 74% of the blood culture-positive cases of typhoid fever. However, 14% of the positive results would be false-positive, and 10% of the negative results would be false-negative. The Widal test can be helpful in the laboratory diagnosis of typhoid fever in Vietnam if interpreted with care. PMID:10449469
The Lancet Weight Determines Wheal Diameter in Response to Skin Prick Testing with Histamine.
Andersen, Hjalte H; Lundgaard, Anna Charlotte; Petersen, Anne S; Hauberg, Lise E; Sharma, Neha; Hansen, Sofie D; Elberling, Jesper; Arendt-Nielsen, Lars
2016-01-01
Skin prick test (SPT) is a common test for diagnosing immunoglobulin E-mediated allergies. In clinical routine, technicalities, human errors or patient-related biases, occasionally results in suboptimal diagnosis of sensitization. Although not previously assessed qualitatively, lancet weight is hypothesized to be important when performing SPT to minimize the frequency of false positives, false negatives, and unwanted discomfort. Accurate weight-controlled SPT was performed on the volar forearms and backs of 20 healthy subjects. Four predetermined lancet weights were applied (25 g, 85 g, 135 g and 265 g) using two positive control histamine solutions (1 mg/mL and 10 mg/mL) and one negative control (saline). A total of 400 SPTs were conducted. The outcome parameters were: wheal size, neurogenic inflammation (measured by superficial blood perfusion), frequency of bleeding, and the lancet provoked pain response. The mean wheal diameter increased significantly as higher weights were applied to the SPT lancet, e.g. from 3.2 ± 0.28 mm at 25 g to 5.4 ± 1.7 mm at 265 g (p<0.01). Similarly, the frequency of bleeding, the provoked pain, and the neurogenic inflammatory response increased significantly. At 265 g saline evoked two wheal responses (/160 pricks) below 3 mm. The applied weight of the lancet during the SPT-procedure is an important factor. Higher lancet weights precipitate significantly larger wheal reactions with potential diagnostic implications. This warrants additional research of the optimal lancet weight in relation to SPT-guidelines to improve the specificity and sensitivity of the procedure.
The Lancet Weight Determines Wheal Diameter in Response to Skin Prick Testing with Histamine
Andersen, Hjalte H.; Elberling, Jesper; Arendt-Nielsen, Lars
2016-01-01
Background Skin prick test (SPT) is a common test for diagnosing immunoglobulin E-mediated allergies. In clinical routine, technicalities, human errors or patient-related biases, occasionally results in suboptimal diagnosis of sensitization. Objective Although not previously assessed qualitatively, lancet weight is hypothesized to be important when performing SPT to minimize the frequency of false positives, false negatives, and unwanted discomfort. Methods Accurate weight-controlled SPT was performed on the volar forearms and backs of 20 healthy subjects. Four predetermined lancet weights were applied (25 g, 85 g, 135 g and 265 g) using two positive control histamine solutions (1 mg/mL and 10 mg/mL) and one negative control (saline). A total of 400 SPTs were conducted. The outcome parameters were: wheal size, neurogenic inflammation (measured by superficial blood perfusion), frequency of bleeding, and the lancet provoked pain response. Results The mean wheal diameter increased significantly as higher weights were applied to the SPT lancet, e.g. from 3.2 ± 0.28 mm at 25 g to 5.4 ± 1.7 mm at 265 g (p<0.01). Similarly, the frequency of bleeding, the provoked pain, and the neurogenic inflammatory response increased significantly. At 265 g saline evoked two wheal responses (/160 pricks) below 3 mm. Conclusion and clinical relevance The applied weight of the lancet during the SPT-procedure is an important factor. Higher lancet weights precipitate significantly larger wheal reactions with potential diagnostic implications. This warrants additional research of the optimal lancet weight in relation to SPT-guidelines to improve the specificity and sensitivity of the procedure. PMID:27213613
Automated classification of neurological disorders of gait using spatio-temporal gait parameters.
Pradhan, Cauchy; Wuehr, Max; Akrami, Farhoud; Neuhaeusser, Maximilian; Huth, Sabrina; Brandt, Thomas; Jahn, Klaus; Schniepp, Roman
2015-04-01
Automated pattern recognition systems have been used for accurate identification of neurological conditions as well as the evaluation of the treatment outcomes. This study aims to determine the accuracy of diagnoses of (oto-)neurological gait disorders using different types of automated pattern recognition techniques. Clinically confirmed cases of phobic postural vertigo (N = 30), cerebellar ataxia (N = 30), progressive supranuclear palsy (N = 30), bilateral vestibulopathy (N = 30), as well as healthy subjects (N = 30) were recruited for the study. 8 measurements with 136 variables using a GAITRite(®) sensor carpet were obtained from each subject. Subjects were randomly divided into two groups (training cases and validation cases). Sensitivity and specificity of k-nearest neighbor (KNN), naive-bayes classifier (NB), artificial neural network (ANN), and support vector machine (SVM) in classifying the validation cases were calculated. ANN and SVM had the highest overall sensitivity with 90.6% and 92.0% respectively, followed by NB (76.0%) and KNN (73.3%). SVM and ANN showed high false negative rates for bilateral vestibulopathy cases (20.0% and 26.0%); while KNN and NB had high false negative rates for progressive supranuclear palsy cases (76.7% and 40.0%). Automated pattern recognition systems are able to identify pathological gait patterns and establish clinical diagnosis with good accuracy. SVM and ANN in particular differentiate gait patterns of several distinct oto-neurological disorders of gait with high sensitivity and specificity compared to KNN and NB. Both SVM and ANN appear to be a reliable diagnostic and management tool for disorders of gait. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sentinel lymph node mapping in melanoma: the issue of false-negative findings.
Manca, Gianpiero; Rubello, Domenico; Romanini, Antonella; Boni, Giuseppe; Chiacchio, Serena; Tredici, Manuel; Mazzarri, Sara; Duce, Valerio; Colletti, Patrick M; Volterrani, Duccio; Mariani, Giuliano
2014-07-01
Management of cutaneous melanoma has changed after introduction in the clinical routine of sentinel lymph node biopsy (SLNB) for nodal staging. By defining the nodal basin status, SLNB provides a powerful prognostic information. Nevertheless, some debate still surrounds the accuracy of this procedure in terms of false-negative rate. Several large-scale studies have reported a relatively high false-negative rate (5.6%-21%), correctly defined as the proportion of false-negative results with respect to the total number of "actual" positive lymph nodes. In this review, we identified all the technical aspects that the nuclear medicine physician, the surgeon, and the pathologist should take into account to improve accuracy of the procedure and minimize the false-negative rate. In particular, SPECT/CT imaging detects more SLNs than those found by planar lymphoscintigraphy. Furthermore, the nuclear medicine community should reach a consensus on the radioactive counting rate threshold to better guide the surgeon in identifying the lymph nodes with the highest likelihood of housing metastases ("true biologic SLNs"). Analysis of the harvested SLNs by conventional techniques is also a further potential source for error. More accurate SLN analysis (eg, molecular analysis by reverse transcriptase-polymerase chain reaction) and more extensive SLN sampling identify more positive nodes, thus reducing the false-negative rate.The clinical factors identifying patients at higher-risk local recurrence after a negative SLNB include older age at diagnosis, deeper lesions, histological ulceration, and head-neck anatomic location of the primary lesion.The clinical impact of a false-negative SLNB on the prognosis of melanoma patients remains controversial, because the majority of studies have failed to demonstrate overall statistically significant disadvantage in melanoma-specific survival for false-negative SLNB patients compared with true-positive SLNB patients.When new more effective drugs will be available in the adjuvant setting for stage III melanoma patients, the implication of an accurate staging procedure for the sentinel lymph nodes will be crucial for both patients and clinicians. Standardization and accuracy of SLN identification, removal, and analysis are required.
Value of 18F-FDG PET/CT in diagnosing chronic Q fever in patients with central vascular disease.
Hagenaars, J C J P; Wever, P C; Vlake, A W; Renders, N H M; van Petersen, A S; Hilbink, M; de Jager-Leclercq, M G L; Moll, F L; Koning, O H J; Hoekstra, C J
2016-08-01
The aim of this study is to describe the value of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) in diagnosing chronic Q fever in patients with central vascular disease and the added value of 18F-FDG PET/CT in the diagnostic combination strategy as described in the Dutch consensus guideline for diagnosing chronic Q fever. 18F-FDG PET/CT was performed in patients with an abdominal aortic aneurysm or aorto-iliac reconstruction and chronic Q fever, diagnosed by serology and positive PCR for Coxiella burnetii DNA in blood and/or tissue (PCR-positive study group). Patients with an abdominal aortic aneurysm or aorto-iliac reconstruction without clinical and serological findings indicating Q fever infection served as a control group. Patients with a serological profile of chronic Q fever and a negative PCR in blood were included in additional analyses (PCR-negative study group). Thirteen patients were evaluated in the PCR-positive study group and 22 patients in the control group. 18F-FDG PET/CT indicated vascular infection in 6/13 patients in the PCR-positive study group and 2/22 patients in the control group. 18F-FDG PET/CT demonstrated a sensitivity of 46% (95% CI: 23-71%), specificity of 91% (95% CI: 71-99%), positive predictive value of 75% (95% CI:41-93%) and negative predictive value of 74% (95% CI: 55-87%). In the PCR-negative study group, 18F-FDG PET/CT was positive in 10/20 patients (50%). The combination of 18F-FDG PET/CT, as an imaging tool for identifying a focus of infection, and Q fever serology is a valid diagnostic strategy for diagnosing chronic Q fever in patients with central vascular disease.
Shrestha, Ram K; Sansom, Stephanie L; Richardson-Moore, April; French, P Tyler; Scalco, Beth; Lalota, Marlene; Llanas, Michelle; Stodola, James; Macgowan, Robin; Margolis, Andrew
2009-02-01
To assess the costs of rapid human immunodeficiency virus (HIV) testing and counseling to identify new diagnoses of HIV infection among jail inmates. We obtained program costs and testing outcomes from rapid HIV testing and counseling services provided in jails from March 1, 2004, through February 28, 2005, in Florida, Louisiana, New York, and Wisconsin. We obtained annual program delivery costs-fixed and variable costs-from each project area. We estimated the average cost of providing counseling and testing to HIV-negative and HIV-infected inmates and estimated the cost per newly diagnosed HIV infection. In the 4 project areas, 17,433 inmates (range, 2185-6463) were tested: HIV infection was diagnosed for 152 inmates (range, 4-81). The average cost of testing ranged from $29.46 to $44.98 for an HIV-negative inmate and from $71.37 to $137.72 for an HIV-infected inmate. The average cost per newly diagnosed HIV infection ranged from $2,451 to $25,288. Variable costs were 61% to 86% of total costs. The cost of identifying jail inmates with newly diagnosed HIV infection by using rapid HIV testing varied according to the prevalence of undiagnosed HIV infection among inmates tested in project areas. Variations in the cost of testing HIV-negative and HIV-infected inmates were because of the differences in wages, travel to the jails, and the amount of time spent on counseling and testing. Program managers can use these data to gauge the cost of initiating counseling and testing programs in jails or to streamline current programs.
Patient characteristics associated with false arrhythmia alarms in intensive care
Harris, Patricia R; Zègre-Hemsey, Jessica K; Schindler, Daniel; Bai, Yong; Pelter, Michele M; Hu, Xiao
2017-01-01
Introduction A high rate of false arrhythmia alarms in the intensive care unit (ICU) leads to alarm fatigue, the condition of desensitization and potentially inappropriate silencing of alarms due to frequent invalid and nonactionable alarms, often referred to as false alarms. Objective The aim of this study was to identify patient characteristics, such as gender, age, body mass index, and diagnosis associated with frequent false arrhythmia alarms in the ICU. Methods This descriptive, observational study prospectively enrolled patients who were consecutively admitted to one of five adult ICUs (77 beds) at an urban medical center over a period of 31 days in 2013. All monitor alarms and continuous waveforms were stored on a secure server. Nurse scientists with expertise in cardiac monitoring used a standardized protocol to annotate six clinically important types of arrhythmia alarms (asystole, pause, ventricular fibrillation, ventricular tachycardia, accelerated ventricular rhythm, and ventricular bradycardia) as true or false. Total monitoring time for each patient was measured, and the number of false alarms per hour was calculated for these six alarm types. Medical records were examined to acquire data on patient characteristics. Results A total of 461 unique patients (mean age =60±17 years) were enrolled, generating a total of 2,558,760 alarms, including all levels of arrhythmia, parameter, and technical alarms. There were 48,404 hours of patient monitoring time, and an average overall alarm rate of 52 alarms/hour. Investigators annotated 12,671 arrhythmia alarms; 11,345 (89.5%) were determined to be false. Two hundred and fifty patients (54%) generated at least one of the six annotated alarm types. Two patients generated 6,940 arrhythmia alarms (55%). The number of false alarms per monitored hour for patients’ annotated arrhythmia alarms ranged from 0.0 to 7.7, and the duration of these false alarms per hour ranged from 0.0 to 158.8 seconds. Patient characteristics were compared in relation to 1) the number and 2) the duration of false arrhythmia alarms per 24-hour period, using nonparametric statistics to minimize the influence of outliers. Among the significant associations were the following: age ≥60 years (P=0.013; P=0.034), confused mental status (P<0.001 for both comparisons), cardiovascular diagnoses (P<0.001 for both comparisons), electrocardiographic (ECG) features, such as wide ECG waveforms that correspond to ventricular depolarization known as QRS complex due to bundle branch block (BBB) (P=0.003; P=0.004) or ventricular paced rhythm (P=0.002 for both comparisons), respiratory diagnoses (P=0.004 for both comparisons), and support with mechanical ventilation, including those with primary diagnoses other than respiratory ones (P<0.001 for both comparisons). Conclusion Patients likely to trigger a higher number of false arrhythmia alarms may be those with older age, confusion, cardiovascular diagnoses, and ECG features that indicate BBB or ventricular pacing, respiratory diagnoses, and mechanical ventilatory support. Algorithm improvements could focus on better noise reduction (eg, motion artifact with confused state) and distinguishing BBB and paced rhythms from ventricular arrhythmias. Increasing awareness of patient conditions that apparently trigger a higher rate of false arrhythmia alarms may be useful for reducing unnecessary noise and improving alarm management. PMID:28458554
True detection limits in an experimental linearly heteroscedastic system.. Part 2
NASA Astrophysics Data System (ADS)
Voigtman, Edward; Abraham, Kevin T.
2011-11-01
Despite much different processing of the experimental fluorescence detection data presented in Part 1, essentially the same estimates were obtained for the true theoretical Currie decision levels ( YC and XC) and true Currie detection limits ( YD and XD). The obtained experimental values, for 5% probability of false positives and 5% probability of false negatives, were YC = 56.0 mV, YD = 125. mV, XC = 0.132 μg/mL and XD = 0.293 μg/mL. For 5% probability of false positives and 1% probability of false negatives, the obtained detection limits were YD = 158 . mV and XD = 0.371 μg/mL. Furthermore, by using bootstrapping methodology on the experimental data for the standards and the analytical blank, it was possible to validate previously published experimental domain expressions for the decision levels ( yC and xC) and detection limits ( yD and xD). This was demonstrated by testing the generated decision levels and detection limits for their performance in regard to false positives and false negatives. In every case, the obtained numbers of false negatives and false positives were as specified a priori.
Durrett, Christine; Trull, Timothy J
2005-09-01
Two personality models are compared regarding their relationship with personality disorder (PD) symptom counts and with lifetime Axis I diagnoses. These models share 5 similar domains, and the Big 7 model also includes 2 domains assessing self-evaluation: positive and negative valence. The Big 7 model accounted for more variance in PDs than the 5-factor model, primarily because of the association of negative valence with most PDs. Although low-positive valence was associated with most Axis I diagnoses, the 5-factor model generally accounted for more variance in Axis I diagnoses than the Big 7 model. Some predicted associations between self-evaluation and psychopathology were not found, and unanticipated associations emerged. These findings are discussed regarding the utility of evaluative terms in clinical assessment.
De Dieu Longo, Jean; Bouassa, Ralph-Sydney Mboumba; Simaleko, Marcel Mbeko; Kouabosso, André; Mossoro-Kpinde, Christian Diamant; Robin, Leman; Charmant, Laura; Grésenguet, Gérard; Bélec, Laurent
2018-05-02
Adult outpatients attending the main sexually transmitted infections clinic of Bangui, Central African Republic, were prospectively subjected to multiplex rapid diagnostic test for HIV, HBV and HCV. In group I (n=208) of patients already followed for HIV, 6 (2.9%) were unexpectedly negative, thus corresponding to false positive for HIV by the national HIV algorithm; HBsAg- and HCV- positivities were high (18.7% and 4.3%, respectively). In group II (n=71) of patients with unknown HIV status, at least one chronic viral disease was diagnosed in 26 (36.6%) patients, including 5 (7.1%) HIV, 17 (23.9%) HBV and 3 (4.2%) HCV infections. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Korkala, O L; Isotalo, T M; Lavonius, M I; Niskanen, R O
1995-01-01
In a follow-up study of 67 patients with an arthroscopically diagnosed patellar chondromalacia, we compared the results of plain conservative treatment with those after an open lateral retinacular release. The mean follow-up was 35 months. In Grade I chondromalacia the lateral release did not affect the result, which was in all cases good or excellent. In Grade II to IV chondromalacia the lateral release appeared beneficial, although the difference did not reach statistical significance. We also examined the validity of three clinical signs in arthroscopically verified patellar chondromalacia. Patellar inhibition and tracking tests were clearly more sensitive than the lateral apprehension test, which often gave a false negative result. If the patellar inhibition test is positive and a Grade II to IV chondromalacia of the patella is found at arthroscopy, lateral release should be considered among other procedures, like patellar shaving or patellar resurfacing.
[Wound botulism in heroin addicts in Germany].
Kuhn, J; Gerbershagen, K; Schaumann, R; Langenberg, U; Rodloff, A C; Mueller, W; Hartmann-Klosterkoetter, U; Bewermeyer, H
2006-05-05
5 heroin addicts (aged 31-44 years; 1 female, 4 men) presented with a history of blurred vision and diplopia followed by dysarthria. 3 of the patients also developed respiratory failure requiring long-term ventilatory support. Physical examination revealed cranial nerve deficits and abscesses at injection sites in 3 of them. In 4 patients wound botulism was diagnosed on the basis of symptoms, course of the illness and response to specific treatment. Clostridium botulinum was grown from wound swab in one patient. Two of the patients, having been injected with antitoxin immediately after admission, were discharged almost symptom-free after only a few days. Adjuvant antibiotics and, in 3 patients, surgical débridement of the abscesses were needed. Progressive cranial nerve pareses in addicts who inject drugs intravenously or intramuscularly should raise the suspicion of wound botulism and require hospitalization. While indirect demonstration of toxin supports the diagnosis, false-negative results are common.
Bellassen, Virginie; Iglói, Kinga; de Souza, Leonardo Cruz; Dubois, Bruno; Rondi-Reig, Laure
2012-02-08
Episodic memory impairment is a hallmark for early diagnosis of Alzheimer's disease. Most actual tests used to diagnose Alzheimer's disease do not assess the spatiotemporal properties of episodic memory and lead to false-positive or -negative diagnosis. We used a newly developed, nonverbal navigation test for Human, based on the objective experimental testing of a spatiotemporal experience, to differentially Alzheimer's disease at the mild stage (N = 16 patients) from frontotemporal lobar degeneration (N = 11 patients) and normal aging (N = 24 subjects). Comparing navigation parameters and standard neuropsychological tests, temporal order memory appeared to have the highest predictive power for mild Alzheimer's disease diagnosis versus frontotemporal lobar degeneration and normal aging. This test was also nonredundant with classical neuropsychological tests. As a conclusion, our results suggest that temporal order memory tested in a spatial navigation task may provide a selective behavioral marker of Alzheimer's disease.
Narita, Kazuto; Ishii, Yuuki; Vo, Phuc Thi Hong; Nakagawa, Fumiko; Ogata, Shinichi; Yamashita, Kunihiko; Kojima, Hajime; Itagaki, Hiroshi
2018-01-01
Recently, animal testing has been affected by increasing ethical, social, and political concerns regarding animal welfare. Several in vitro safety tests for evaluating skin sensitization, such as the human cell line activation test (h-CLAT), have been proposed. However, similar to other tests, the h-CLAT has produced false-negative results, including in tests for acid anhydride and water-insoluble chemicals. In a previous study, we demonstrated that the cause of false-negative results from phthalic anhydride was hydrolysis by an aqueous vehicle, with IL-8 release from THP-1 cells, and that short-time exposure to liquid paraffin (LP) dispersion medium could reduce false-negative results from acid anhydrides. In the present study, we modified the h-CLAT by applying this exposure method. We found that the modified h-CLAT is a promising method for reducing false-negative results obtained from acid anhydrides and chemicals with octanol-water partition coefficients (LogK ow ) greater than 3.5. Based on the outcomes from the present study, a combination of the original and the modified h-CLAT is suggested for reducing false-negative results. Notably, the combination method provided a sensitivity of 95% (overall chemicals) or 93% (chemicals with LogK ow > 2.0), and an accuracy of 88% (overall chemicals) or 81% (chemicals with LogK ow > 2.0). We found that the combined method is a promising evaluation scheme for reducing false-negative results seen in existing in vitro skin-sensitization tests. In the future, we expect a combination of original and modified h-CLAT to be applied in a newly developed in vitro test for evaluating skin sensitization.
False negative cytology in large thyroid nodules.
Giles, Wesley H; Maclellan, Reid A; Gawande, Atul A; Ruan, Daniel T; Alexander, Erik K; Moore, Francis D; Cho, Nancy L
2015-01-01
Controversy exists regarding the accuracy of fine-needle aspiration (FNA) in large thyroid nodules. Recent surgical series have documented false-negative rates ranging from 0.7 to 13 %. We examined the accuracy of benign FNA cytology in patients with thyroid nodules ≥3 cm who underwent surgical resection and identified features characteristic of false-negative results. We retrospectively studied all thyroidectomy specimens between January 2009 and October 2011 and identified nodules ≥3 cm with corresponding benign preoperative FNA cytology. We collected clinical information regarding patient demographics, nodule size, symptoms, sonographic features, FNA results, and final surgical pathology. For comparison, we analyzed nodules <3 cm from this cohort also with benign FNA cytology. A total of 323 nodules with benign preoperative cytology were identified. Eighty-three nodules were <3 cm, 94 nodules were 3-3.9 cm, and 146 nodules were ≥4 cm in size. The false-negative rate was 11.7 % for all nodules ≥3 cm and 4.8 % for nodules <3 cm (p = 0.03). Subgroup analysis of nodules ≥3 cm revealed a false-negative rate of 12.8 % for nodules 3-3.9 cm and 11 % for nodules ≥4 cm. Age ≥55 years and asymptomatic clinical status were the only patient characteristics that reached statistical significance as risk factors. Final pathology of the false-negative specimens consisted mainly of follicular variant of papillary thyroid cancer and follicular thyroid cancer. When referred for thyroidectomy, patients with large thyroid nodules demonstrate a modest, yet significant, false-negative rate despite initial benign aspiration cytology. Therefore, thyroid nodules ≥3 cm may be considered for removal even when referred with benign preoperative cytology.
Can missed breast cancer be recognized by regular peer auditing on screening mammography?
Pan, Huay-Ben; Yang, Tsung-Lung; Hsu, Giu-Cheng; Chiang, Chia-Ling; Huang, Jer-Shyung; Chou, Chen-Pin; Wang, Yen-Chi; Liang, Huei-Lung; Lee, San-Kan; Chou, Yi-Hong; Wong, Kam-Fai
2012-09-01
This study was conducted to investigate whether detectable missed breast cancers could be distinguished from truly false negative images in a mammographic screening by a regular peer auditing. Between 2004 and 2007, a total of 311,193 free nationwide biennial mammographic screenings were performed for 50- to 69-year-old women in Taiwan. Retrospectively comparing the records in Taiwan's Cancer registry, 1283 cancers were detected (4.1 per 1000). Of the total, 176 (0.6 per 1000) initial mammographic negative assessments were reported to have cancers (128 traditional films and 48 laser-printed digital images). We selected 186 true negative films (138 traditional films and 48 laser-printed ones) as control group. These were seeded into 4815 films of 2008 images to be audited in 2009. Thirty-four auditors interpreted all the films in a single-blind, randomized, pair-control study. The performance of 34 auditors was analyzed by chi-square test. A p value of < 0.05 was considered significant. Eight (6 traditional and 2 digital films) of the 176 false negative films were not reported by the auditors (missing rate of 4.5%). Of this total, 87 false negatives were reassessed as positive, while 29 of the 186 true negatives were reassessed as positive, making the overall performance of the 34 auditors in interpreting the false negatives and true negatives a specificity of 84.4% and sensitivity of 51.8%. The specificity and sensitivity in traditional films and laser-printed films were 98.6% versus 43.8% and 41.8% versus 78.3%, respectively. Almost 42% of the traditional false negative films had positive reassessment by the auditors, showing a significant difference from the initial screeners (p < 0.001). The specificity of their reinterpretation of laser-printed films was obviously low. Almost 42% of the false negative traditional films were judged as missed cancers in this study. A peer auditing should reduce the probability of missed cancers. 2012 Published by Elsevier B.V
Diagnosing periprosthetic infection: false-positive intraoperative Gram stains.
Oethinger, Margret; Warner, Debra K; Schindler, Susan A; Kobayashi, Hideo; Bauer, Thomas W
2011-04-01
Intraoperative Gram stains have a reported low sensitivity but high specificity when used to help diagnose periprosthetic infections. In early 2008, we recognized an unexpectedly high frequency of apparent false-positive Gram stains from revision arthroplasties. The purpose of this report is to describe the cause of these false-positive test results. We calculated the sensitivity and specificity of all intraoperative Gram stains submitted from revision arthroplasty cases during a 3-month interval using microbiologic cultures of the same samples as the gold standard. Methods of specimen harvesting, handling, transport, distribution, specimen processing including tissue grinding/macerating, Gram staining, and interpretation were studied. After a test modification, results of specimens were prospectively collected for a second 3-month interval, and the sensitivity and specificity of intraoperative Gram stains were calculated. The retrospective review of 269 Gram stains submitted from revision arthroplasties indicated historic sensitivity and specificity values of 23% and 92%, respectively. Systematic analysis of all steps of the procedure identified Gram-stained but nonviable bacteria in commercial broth reagents used as diluents for maceration of periprosthetic membranes before Gram staining and culture. Polymerase chain reaction and sequencing showed mixed bacterial DNA. Evaluation of 390 specimens after initiating standardized Millipore filtering of diluent fluid revealed a reduced number of positive Gram stains, yielding 9% sensitivity and 99% specificity. Clusters of false-positive Gram stains have been reported in other clinical conditions. They are apparently rare related to diagnosing periprosthetic infections but have severe consequences if used to guide treatment. Even occasional false-positive Gram stains should prompt review of laboratory methods. Our observations implicate dead bacteria in microbiologic reagents as potential sources of false-positive Gram stains.
A statistical model of false negative and false positive detection of phase singularities.
Jacquemet, Vincent
2017-10-01
The complexity of cardiac fibrillation dynamics can be assessed by analyzing the distribution of phase singularities (PSs) observed using mapping systems. Interelectrode distance, however, limits the accuracy of PS detection. To investigate in a theoretical framework the PS false negative and false positive rates in relation to the characteristics of the mapping system and fibrillation dynamics, we propose a statistical model of phase maps with controllable number and locations of PSs. In this model, phase maps are generated from randomly distributed PSs with physiologically-plausible directions of rotation. Noise and distortion of the phase are added. PSs are detected using topological charge contour integrals on regular grids of varying resolutions. Over 100 × 10 6 realizations of the random field process are used to estimate average false negative and false positive rates using a Monte-Carlo approach. The false detection rates are shown to depend on the average distance between neighboring PSs expressed in units of interelectrode distance, following approximately a power law with exponents in the range of 1.14 to 2 for false negatives and around 2.8 for false positives. In the presence of noise or distortion of phase, false detection rates at high resolution tend to a non-zero noise-dependent lower bound. This model provides an easy-to-implement tool for benchmarking PS detection algorithms over a broad range of configurations with multiple PSs.
Media use, cancer knowledge and lifestyle choices: a cross-sectional analysis.
Nelissen, Sara; Beullens, Kathleen; Lemal, Marijke; Van den Bulck, Jan
2015-10-01
Both media use and cancer knowledge have been identified as important predictors of a healthy lifestyle. However, little is known about the interplay between these two variables, and about differences between cancer diagnosed and non-diagnosed consumers of media and knowledge. This study investigated the relationship between media use (television and internet exposure) and lifestyle choices of cancer diagnosed and non-diagnosed individuals, and looked at the influence of cancer knowledge on this relationship. A cross-sectional, quantitative survey (the Leuven Cancer Information Survey) was administered to 621 cancer diagnosed and 1387 non-diagnosed individuals, aged 16-88 years old in Flanders (Belgium). Bivariate analyses, hierarchical linear regression analyses and advanced moderation and mediation analyses were conducted. Internet exposure was not a predictor of lifestyle choices. Television exposure, however, was a negative predictor of healthy lifestyle choices. Moreover, television exposure was a direct negative predictor of cancer knowledge, which in turn positively predicted lifestyle choices. However, no differences were found in the investigated relationships between the two subsamples. These results indicate that higher levels of television exposure coincide with less cancer knowledge and with less healthy lifestyle choices. It offers a pathway for intervention by suggesting that improving cancer knowledge through television might positively affect lifestyle choices. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
Zavadovskaya, V D; Zorkal'tsev, M A; Udodov, V D; Zamyshevskaya, M A; Kilina, O Yu; Kurazhov, A P; Popov, K M
2015-01-01
To give the results of a software-based hybrid single photon emission computed tomography/magnetic resonance imaging (SPECT/MRI) in detecting osteomyelitis (OM) in patients with diabetic foot syndrome (DFS). Seventy-six patients (35 men and 41 women) (mean age, 59.4 +/- 7.1 years) with type 1 and 2 diabetes mellitus and suspected OM were examined. The investigation enrolled patients with neuropathic (n = 25), ischemic (n = 13), and mixed (n = 38) DFS. All the patients underwent (99m)Tc-HMPAO/ (99m)Tc-technefit labeled leukocyte scintigraphy; magnetic resonance imaging was performed in 30 patients. The results were combined using RView 9.06 software (Colin Studholme). Labeled leukocyte SPECT to Diagnose OM yielded 255 true positive (TP), 38 true negative (TN), 12 false negative (FP), and 1 false negative (FN) results. The accuracy of the technique was 82.9%. The FP results were due to the low resolution of the technique and to the small sizes of the object under study. One FN result was detected in a patient with ischemic DFS because of reduced blood flow. MRI to identify OM in patients with DFS provided 20 TP, 16 TN, 4 FP, and 2 FN results. Its diagnostic accuracy was 85.7%. The relative low specificity of MRI was associated with the presence of FP results due to the complexity of differential diagnosis of bone marrow edema and inflammatory infiltration. Assessing 42 hybrid SPECT/MR-images revealed 21 TP, 17 TN, 3 FP, and I FN results. The diagnostic accuracy was equal to 95.9%. Thus, comparing MRI (90.9% sensitivity and 80.0% specificity), labeled leukocyte scintigraphy (96.2% sensitivity and 76.0% specificity), and hybrid SPECT/MRI (95.5% sensitivity and 85.0% specificity) showed the high diagnostic efficiency of the latter.
Paulus, Elena M; Fabian, Timothy C; Savage, Stephanie A; Zarzaur, Ben L; Botta, Vandana; Dutton, Wesley; Croce, Martin A
2014-02-01
Aggressive screening to diagnose blunt cerebrovascular injury (BCVI) results in early treatment, leading to improved outcomes and reduced stroke rates. While computed tomographic angiography (CTA) has been widely adopted for BCVI screening, evidence of its diagnostic sensitivity is marginal. Previous work from our institution using 32-channel multidetector CTA in 684 patients demonstrated an inadequate sensitivity of 51% (Ann Surg. 2011,253: 444-450). Digital subtraction angiography (DSA) continues to be the reference standard of diagnosis but has significant drawbacks of invasiveness and resource demands. There have been continued advances in CT technology, and this is the first report of an extensive experience with 64-channel multidetector CTA. Patients screened for BCVI using CTA and DSA (reference) at a Level 1 trauma center during the 12-month period ending in May 2012 were identified. Results of CTA and DSA, complications, and strokes were retrospectively reviewed and compared. A total of 594 patients met criteria for BCVI screening and underwent both CTA and DSA. One hundred twenty-eight patients (22% of those screened) had 163 injured vessels: 99 (61%) carotid artery injuries and 64 (39%) vertebral artery injuries. Sixty-four-channel CTA demonstrated an overall sensitivity per vessel of 68% and specificity of 92%. The 52 false-negative findings on CTA were composed of 34 carotid artery injuries and 18 vertebral artery injuries; 32 (62%) were Grade I injuries. Overall, positive predictive value was 36.2%, and negative predictive value was 97.5%. Six procedure-related complications (1%) occurred with DSA, including two iatrogenic dissections and one stroke. Sixty-four-channel CTA demonstrated a significantly improved sensitivity of 68% versus the 51% previously reported for the 32-channel CTA (p = 0.0075). Sixty-two percent of the false-negative findings occurred with low-grade injuries. Considering complications, cost, and resource demand associated with DSA, this study suggests that 64-channel CTA may replace DSA as the primary screening tool for BCVI. Diagnostic study, level III.
Zhang, Xi; Lin, Xi; Tan, Yanjuan; Zhu, Ying; Wang, Hui; Feng, Ruimei; Tang, Guoxue; Zhou, Xiang; Li, Anhua; Qiao, Youlin
2018-04-01
The automated breast ultrasound system (ABUS) is a potential method for breast cancer detection; however, its diagnostic performance remains unclear. We conducted a hospital-based multicenter diagnostic study to evaluate the clinical performance of the ABUS for breast cancer detection by comparing it to handheld ultrasound (HHUS) and mammography (MG). Eligible participants underwent HHUS and ABUS testing; women aged 40-69 years additionally underwent MG. Images were interpreted using the Breast Imaging Reporting and Data System (BI-RADS). Women in the BI-RADS categories 1-2 were considered negative. Women classified as BI-RADS 3 underwent magnetic resonance imaging to distinguish true- and false-negative results. Core aspiration or surgical biopsy was performed in women classified as BI-RADS 4-5, followed by a pathological diagnosis. Kappa values and agreement rates were calculated between ABUS, HHUS and MG. A total of 1,973 women were included in the final analysis. Of these, 1,353 (68.6%) and 620 (31.4%) were classified as BI-RADS categories 1-3 and 4-5, respectively. In the older age group, the agreement rate and Kappa value between the ABUS and HHUS were 94.0% and 0.860 (P<0.001), respectively; they were 89.2% and 0.735 (P<0.001) between the ABUS and MG, respectively. Regarding consistency between imaging and pathology results, 78.6% of women classified as BI-RADS 4-5 based on the ABUS were diagnosed with precancerous lesions or cancer; which was 7.2% higher than that of women based on HHUS. For BI-RADS 1-2, the false-negative rates of the ABUS and HHUS were almost identical and were much lower than those of MG. We observed a good diagnostic reliability for the ABUS. Considering its performance for breast cancer detection in women with high-density breasts and its lower operator dependence, the ABUS is a promising option for breast cancer detection in China.
Corson-Knowles, Daniel; Russell, Frances M
2018-05-01
Clinical ultrasound (CUS) is highly specific for the diagnosis of acute appendicitis but is operator-dependent. The goal of this study was to determine if a heterogeneous group of emergency physicians (EP) could diagnose acute appendicitis on CUS in patients with a moderate to high pre-test probability. This was a prospective, observational study of a convenience sample of adult and pediatric patients with suspected appendicitis. Sonographers received a structured, 20-minute CUS training on appendicitis prior to patient enrollment. The presence of a dilated (>6 mm diameter), non-compressible, blind-ending tubular structure was considered a positive study. Non-visualization or indeterminate studies were considered negative. We collected pre-test probability of acute appendicitis based on a 10-point visual analog scale (moderate to high was defined as >3), and confidence in CUS interpretation. The primary objective was measured by comparing CUS findings to surgical pathology and one week follow-up. We enrolled 105 patients; 76 had moderate to high pre-test probability. Of these, 24 were children. The rate of appendicitis was 36.8% in those with moderate to high pre-test probability. CUS were recorded by 33 different EPs. The sensitivity, specificity, and positive and negative likelihood ratios of EP-performed CUS in patients with moderate to high pre-test probability were 42.8% (95% confidence interval [CI] [25-62.5%]), 97.9% (95% CI [87.5-99.8%]), 20.7 (95% CI [2.8-149.9]) and 0.58 (95% CI [0.42-0.8]), respectively. The 16 false negative scans were all interpreted as indeterminate. There was one false positive CUS diagnosis; however, the sonographer reported low confidence of 2/10. A heterogeneous group of EP sonographers can safely identify acute appendicitis with high specificity in patients with moderate to high pre-test probability. This data adds support for surgical consultation without further imaging beyond CUS in the appropriate clinical setting.
Power, John A; Thompson, Diane V; Rayarao, Geetha; Doyle, Mark; Biederman, Robert W W
2016-05-01
Invasive cardiac catheterization is the venerable "gold standard" for diagnosing constrictive pericarditis. However, its sensitivity and specificity vary dramatically from center to center. Given the ability to unequivocally define segments of the pericardium with the heart via radiofrequency tissue tagging, we hypothesize that cardiac magnetic resonance has the capability to be the new gold standard. All patients who were referred for cardiac magnetic resonance evaluation of constrictive pericarditis underwent cardiac magnetic resonance radiofrequency tissue tagging to define visceral-parietal pericardial adherence to determine constriction. This was then compared with intraoperative surgical findings. Likewise, all preoperative cardiac catheterization testing was reviewed in a blinded manner. A total of 120 patients were referred for clinical suspicion of constrictive pericarditis. Thirty-nine patients were defined as constrictive pericarditis positive solely via radiofrequency tissue-tagging cardiac magnetic resonance, of whom 21 were positive, 4 were negative, and 1 was equivocal for constrictive pericarditis, as defined by cardiac catheterization. Of these patients, 16 underwent pericardiectomy and were surgically confirmed. There was 100% agreement between cardiac magnetic resonance-defined constrictive pericarditis positivity and postsurgical findings. No patients were misclassified by cardiac magnetic resonance. In regard to the remaining constrictive pericarditis-positive patients defined by cardiac magnetic resonance, 10 were treated medically, declined, were ineligible for surgery, or were lost to follow-up. Long-term follow-up of those who were constrictive pericarditis negative by cardiac magnetic resonance showed no early or late crossover to the surgery arm. Cardiac magnetic resonance via radiofrequency tissue tagging offers a unique, efficient, and effective manner of defining clinically and surgically relevant constrictive pericarditis. Specifically, no patient who was identified with constriction via cardiac magnetic resonance underwent inappropriate sternotomy. However, catheterization had substantial and unacceptable false-positive and false-negative rates with important clinical ramifications. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.
Paek, Se Hyun; Kim, Byung Seup; Kang, Kyung Ho; Kim, Hee Sung
2017-11-13
The BRAF V600E mutation is highly specific for papillary thyroid carcinoma (PTC). A test for this mutation can increase the diagnostic accuracy of fine-needle aspiration cytology (FNAC), but a considerably high false-negative rate for the BRAF V600E mutation on FNAC has been reported. In this study, we investigated the risk factors associated with false-negative BRAF V600E mutation results on FNAC. BRAF V600E mutation results of 221 PTC nodules between December 2011 and June 2013 were retrospectively reviewed. BRAF V600E mutation results on both preoperative FNAC and postoperative formalin-fixed, paraffin-embedded (FFPE) samples were compared. We investigated the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of BRAF V600E mutation results on FNAC. And, we identified the risk factors associated with false-negative results. Of 221 PTC nodules, 150 (67.9%) on FNAC and 185 (83.7%) on FFPE samples were BRAF V600E mutation positive. The sensitivity, specificity, PPV, and NPV for BRAF V600E mutation testing with FNAC were 80.5, 97.2, 99.3, and 49.3%, respectively. Thirty-six (16.3%) BRAF V600E mutation-negative nodules on FNAC were mutation positive on FFPE sample analysis. Risk factors for these false-negative results were age, indeterminate FNAC results (nondiagnostic, atypia of undetermined significance (AUS), and findings suspicious for PTC), and PTC subtype. False-negative rate of BRAF mutation testing with FNAC for thyroid nodules is increased in cases of old age, indeterminate FNAC pathology results, and certain PTC subtypes. Therapeutic surgery can be considered for these cases. A well-designed prospective study with informed consent of patients will be essential for more informative results.
Jiang, Faming; Huang, Weiwei; Wang, Ye; Tian, Panwen; Chen, Xuerong; Liang, Zongan
2016-01-01
Smear-negative pulmonary tuberculosis (PTB) is common and difficult to diagnose. In this study, we investigated the diagnostic value of nucleic acid amplification testing and sequencing combined with acid-fast bacteria (AFB) staining of needle biopsy lung tissues for patients with suspected smear-negative PTB. Patients with suspected smear-negative PTB who underwent percutaneous transthoracic needle biopsy between May 1, 2012, and June 30, 2015, were enrolled in this retrospective study. Patients with AFB in sputum smears were excluded. All lung biopsy specimens were fixed in formalin, embedded in paraffin, and subjected to acid-fast staining and tuberculous polymerase chain reaction (TB-PCR). For patients with positive AFB and negative TB-PCR results in lung tissues, probe assays and 16S rRNA sequencing were used for identification of nontuberculous mycobacteria (NTM). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of PCR and AFB staining were calculated separately and in combination. Among the 220 eligible patients, 133 were diagnosed with TB (men/women: 76/57; age range: 17-80 years, confirmed TB: 9, probable TB: 124). Forty-eight patients who were diagnosed with other specific diseases were assigned as negative controls, and 39 patients with indeterminate final diagnosis were excluded from statistical analysis. The sensitivity, specificity, PPV, NPV, and accuracy of histological AFB (HAFB) for the diagnosis of smear-negative were 61.7% (82/133), 100% (48/48), 100% (82/82), 48.5% (48/181), and 71.8% (130/181), respectively. The sensitivity, specificity, PPV, and NPV of histological PCR were 89.5% (119/133), 95.8% (46/48), 98.3% (119/121), and 76.7% (46/60), respectively, demonstrating that histological PCR had significantly higher accuracy (91.2% [165/181]) than histological acid-fast staining (71.8% [130/181]), P < 0.001. Parallel testing of histological AFB staining and PCR showed the sensitivity, specificity, PPV, NPV, and accuracy to be 94.0% (125/133), 95.8% (46/48), 98.4% (125/127), 85.2% (46/54), and 94.5% (171/181), respectively. Among patients with positive AFB and negative PCR results in lung tissue specimens, two were diagnosed with NTM infections (Mycobacterium avium-intracellulare complex and Mycobacterium kansasii). Nucleic acid amplification testing combined with acid-fast staining in lung biopsy tissues can lead to early and accurate diagnosis in patients with smear-negative pulmonary tuberculosis. For patients with positive histological AFB and negative tuberculous PCR results in lung tissue, NTM infection should be suspected and could be identified by specific probe assays or 16S rRNA sequencing.
Where Have All the Interactions Gone? Estimating the Coverage of Two-Hybrid Protein Interaction Maps
Huang, Hailiang; Jedynak, Bruno M; Bader, Joel S
2007-01-01
Yeast two-hybrid screens are an important method for mapping pairwise physical interactions between proteins. The fraction of interactions detected in independent screens can be very small, and an outstanding challenge is to determine the reason for the low overlap. Low overlap can arise from either a high false-discovery rate (interaction sets have low overlap because each set is contaminated by a large number of stochastic false-positive interactions) or a high false-negative rate (interaction sets have low overlap because each misses many true interactions). We extend capture–recapture theory to provide the first unified model for false-positive and false-negative rates for two-hybrid screens. Analysis of yeast, worm, and fly data indicates that 25% to 45% of the reported interactions are likely false positives. Membrane proteins have higher false-discovery rates on average, and signal transduction proteins have lower rates. The overall false-negative rate ranges from 75% for worm to 90% for fly, which arises from a roughly 50% false-negative rate due to statistical undersampling and a 55% to 85% false-negative rate due to proteins that appear to be systematically lost from the assays. Finally, statistical model selection conclusively rejects the Erdös-Rényi network model in favor of the power law model for yeast and the truncated power law for worm and fly degree distributions. Much as genome sequencing coverage estimates were essential for planning the human genome sequencing project, the coverage estimates developed here will be valuable for guiding future proteomic screens. All software and datasets are available in Datasets S1 and S2, Figures S1–S5, and Tables S1−S6, and are also available from our Web site, http://www.baderzone.org. PMID:18039026
Wu, Shan; Zhang, Xiaofeng; Shuai, Jiangbing; Li, Ke; Yu, Huizhen; Jin, Chenchen
2016-07-04
To simplify the PNA-FISH (Peptide nucleic acid-fluorescence in situ hybridization) test, molecular beacon based PNA probe combined with fluorescence scanning detection technology was applied to replace the original microscope observation to detect Listeria monocytogenes The 5′ end and 3′ end of the L. monocytogenes specific PNA probes were labeled with the fluorescent group and the quenching group respectively, to form a molecular beacon based PNA probe. When PNA probe used for fluorescence scanning and N1 treatment as the control, the false positive rate was 11.4%, and the false negative rate was 0; when N2 treatment as the control, the false positive rate decreased to 4.3%, but the false negative rate rose to 18.6%. When beacon based PNA probe used for fluorescence scanning, taken N1 treatment as blank control, the false positive rate was 8.6%, and the false negative rate was 1.4%; taken N2 treatment as blank control, the false positive rate was 5.7%, and the false negative rate was 1.4%. Compared with PNA probe, molecular beacon based PNA probe can effectively reduce false positives and false negatives. The success rates of hybridization of the two PNA probes were 83.3% and 95.2% respectively; and the rates of the two beacon based PNA probes were 91.7% and 90.5% respectively, which indicated that labeling the both ends of the PNA probe dose not decrease the hybridization rate with the target bacteria. The combination of liquid phase PNA-FISH and fluorescence scanning method, can significantly improve the detection efficiency.
Otgaar, Henry; Howe, Mark L; Muris, Peter
2017-09-01
We examined the creation of spontaneous and suggestion-induced false memories in maltreated and non-maltreated children. Maltreated and non-maltreated children were involved in a Deese-Roediger-McDermott false memory paradigm where they studied and remembered negative and neutral word lists. Suggestion-induced false memories were created using a misinformation procedure during which both maltreated and non-maltreated children viewed a negative video (i.e., bank robbery) and later received suggestive misinformation concerning the event. Our results showed that maltreated children had higher levels of spontaneous negative false memories but lower levels of suggestion-induced false memories as compared to non-maltreated children. Collectively, our study demonstrates that maltreatment both increases and decreases susceptibility to memory illusions depending on the type of false memory being induced. Statement of contribution What is already known on this subject? Trauma affects memory. It is unclear how trauma affects false memory. What does this study add? This study focuses on two types of false memories. © 2017 The Authors. British Journal of Developmental Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.
Should gram stains have a role in diagnosing hip arthroplasty infections?
Johnson, Aaron J; Zywiel, Michael G; Stroh, D Alex; Marker, David R; Mont, Michael A
2010-09-01
The utility of Gram stains in diagnosing periprosthetic infections following total hip arthroplasty has recently been questioned. Several studies report low sensitivity of the test, and its poor ability to either confirm or rule out infection in patients undergoing revision total hip arthroplasty. Despite this, many institutions including that of the senior author continue to perform Gram stains during revision total hip arthroplasty. We assessed the sensitivity, specificity, accuracy, and positive and negative predictive values of Gram stains from surgical-site samplings taken from procedures on patients with both infected and aseptic revision total hip arthroplasties. A review was performed on patients who underwent revision total hip arthroplasty between 2000 and 2007. Eighty-two Gram stains were performed on patients who had infected total hip arthroplasties and underwent revision procedures. Additionally, of the 410 revision total hip arthroplasties performed on patients who were confirmed infection-free, 120 Gram stains were performed. Patients were diagnosed as infected using multiple criteria at the time of surgery. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated from these Gram stain results. The Gram stain demonstrated a sensitivity and specificity of 9.8% and 100%, respectively. In this series, the Gram stain had a negative predictive value of 62%, a positive predictive value of 100%, and an accuracy of 63%. Gram stains obtained from surgical-site samples had poor sensitivity and poor negative predictive value. Based on these findings, as well as those of other authors, we believe that Gram stains should no longer be considered for diagnosing infections in revision total hip arthroplasty. Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.
Tanguy, Michèle; Seguin, Philippe; Laviolle, Bruno; Desbordes, Laurent; Mallédant, Yannick
2005-05-01
To assess clinical safety and accuracy of qualitative blood culture drawn through the hub for ruling out catheter-related infection (CRI). Prospective observational study in a surgical intensive care unit. All patients with sepsis of unknown origin and possibly due to a CRI. Blood culture drawn through a central venous catheter (CVC) just before the catheter was cultured. In 126 patients we investigated 135 cases of sepsis of unknown origin. Using a clinical and bacteriological approach as the reference, the performance of the CVC blood culture was evaluated by the calculation of sensitivity, specificity, and positive and negative predictive values. When CVC blood culture was positive, the time to positivity was considered. Using standard definitions, seven CRIs were diagnosed. CVC blood culture identified five CRIs including the three episodes of catheter-related bacteremia. The method missed two coagulase-negative staphylococcus CRIs without bacteremia. Thirteen false-positive results occurred, including seven bacteremias from a distant source. The CVC blood culture had a sensitivity of 71% (CI 30-95%), specificity of 90% (CI 83-94%), negative predictive value of 98% (CI 93-100%), and positive predictive value of 28% (CI 11-54%). In cases of catheter-related bacteremia the time to positivity of CVC blood culture was 24 h or less. Negative CVC blood culture at 24 h seems useful for management of CVC in selected critically ill surgical patients developing a clinical sepsis. The subsequent risk of catheter-related bacteremia cannot be excluded advocating for an uninterrupted clinical and bacteriological survey.
The impact of non-concordant self-report of substance use in clinical trials research.
Clark, C Brendan; Zyambo, Cosmas M; Li, Ye; Cropsey, Karen L
2016-07-01
Studies comparing self-report substance use data to biochemical verification generally demonstrate high rates of concordance. We argue that these rates are due to the relatively high true negative rate in the general population, and high degree of honestly in treatment seeking individuals. We hypothesized that high risk individuals not seeking treatment would demonstrate low concordance and a high false negative rate of self-reported substance use. A sample of 500 individuals from a smoking cessation clinical trial was assessed over 1 year. Assessments included semi-structured interviews, questionnaires (e.g. Addiction Severity Index, etc.), and urine drug screen assays (UDS). Generalized estimating equations (GEEs) were used to predict false negative reports for various substances across the study and determine the influence of substance use on the primary study outcome of smoking cessation. Participants demonstrated high false negative rates in reporting substances use, and the false negative rates increased as the study progressed. Established predictors of false negatives generalized to the current sample. High concordance and low false negative rates were found in self-report of nicotine use. A small but significant relationship was found in for effect of biochemically verified substance use on smoking cessation. Biochemical verification of substance use is needed in high risk populations involved in studies not directly related to the treatment of substance use, especially in populations with high threat of stigmatization. Testing should continue through the time period of the study for maximal identification of substance use. Copyright © 2016 Elsevier Ltd. All rights reserved.
There was not, they did not: May negation cause the negated ideas to be remembered as existing?
2017-01-01
In this article we demonstrate that negation of ideas can have paradoxical effects, possibly leading the listener to believe that the negated ideas actually existed. In Experiment 1, participants listened to a description of a house, in which some objects were mentioned, some were negated, and some were not mentioned at all. When questioned about the existence of these objects a week later, the participants gave more false positives for items that were negated in the original material than for items that were not mentioned at all, an effect we call negation related false memories (NRFM). The NRFM effect was replicated again in Experiment 2 with a sample of five and six year-old children. Experiment 3 confirmed NRFM in the case of negated actions. The results are discussed in terms of retention hypothesis, as well as the theory that negation can activate a representation of an entity and behaviour. It is also indicated that future research is needed to ensure that it is indeed negation which caused false alarms, not merely mentioning an object. PMID:28448549
Generalized site occupancy models allowing for false positive and false negative errors
Royle, J. Andrew; Link, W.A.
2006-01-01
Site occupancy models have been developed that allow for imperfect species detection or ?false negative? observations. Such models have become widely adopted in surveys of many taxa. The most fundamental assumption underlying these models is that ?false positive? errors are not possible. That is, one cannot detect a species where it does not occur. However, such errors are possible in many sampling situations for a number of reasons, and even low false positive error rates can induce extreme bias in estimates of site occupancy when they are not accounted for. In this paper, we develop a model for site occupancy that allows for both false negative and false positive error rates. This model can be represented as a two-component finite mixture model and can be easily fitted using freely available software. We provide an analysis of avian survey data using the proposed model and present results of a brief simulation study evaluating the performance of the maximum-likelihood estimator and the naive estimator in the presence of false positive errors.
Tamkus, Arvydas A; Rice, Kent S; McCaffrey, Michael T
2018-02-01
Although some authors have published case reports describing false negatives in intraoperative neurophysiological monitoring (IONM), a systematic review of causes of false-negative IONM results is lacking. The objective of this study was to analyze false-negative IONM findings in spine surgery. This is a retrospective cohort analysis. A cohort of 109 patients with new postoperative neurologic deficits was analyzed for possible false-negative IONM reporting. The causes of false-negative IONM reporting were determined. From a cohort of 62,038 monitored spine surgeries, 109 consecutive patients with new postoperative neurologic deficits were reviewed for IONM alarms. Intraoperative neurophysiological monitoring alarms occurred in 87 of 109 surgeries. Nineteen patients with new postoperative neurologic deficits did not have an IONM alarm and surgeons were not warned. In addition, three patients had no interpretable IONM baseline data and no alarms were possible for the duration of the surgery. Therefore, 22 patients were included in the study. The absence of IONM alarms during these 22 surgeries had different origins: "true" false negatives where no waveform changes meeting the alarm criteria occurred despite the appropriate IONM (7); a postoperative development of a deficit (6); failure to monitor the pathway, which became injured (5); the absence of interpretable IONM baseline data which precluded any alarm (3); and technical IONM application issues (1). Overall, the rate of IONM method failing to predict the patient's outcome was very low (0.04%, 22/62,038). Minimizing false negatives requires the application of a proper IONM technique with the limitations of each modality considered in their selection and interpretation. Multimodality IONM provides the most inclusive information, and although it might be impractical to monitor every neural structure that can be at risk, a thorough preoperative consideration of available IONM modalities is important. Delayed development of postoperative deficits cannot be predicted by IONM. Absent baseline IONM data should be treated as an alarm when inconsistent with the patient's preoperative neurologic status. Alarm criteria for IONM may need to be refined for specific procedures and deserves continued study. Copyright © 2017 Elsevier Inc. All rights reserved.
Yang, Bo; Yang, Fujia; Wang, Shanmei; Wang, Qian; Liu, Zhirui; Feng, Wei; Sun, Fengjun; Xia, Peiyuan
2018-05-01
The objective of this study was to analyse the distribution and antimicrobial resistance of bacterial uropathogens isolated from outpatients at Henan Provincial People's Hospital. A total of 1419 samples from 823 newly diagnosed and 596 recurrent UTI outpatients culture positive. Escherichia coli was the most common uropathogen. Compared with the recurrent group, the newly diagnosed group had a higher isolation rate of E. coli and Enterobacter cloacae but a lower isolation rate of Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter spp. Except for P. aeruginosa, the resistance of Gram-negative bacteria to most antibiotics was less than 30%. All Enterococcus and Staphylococcus spp. were sensitive to linezolid, vancomycin and teicoplanin. Both Gram-negative and -positive bacteria exhibited high susceptibility to fosfomycin. Uropathogens isolated from recurrent outpatients had higher resistance rates than did those isolated from newly diagnosed outpatients. Our study indicated that fosfomycin might be an excellent treatment option for outpatients with UTIs.
Triantafyllidou, Olga; Vlachos, Ioannis S; Apostolou, Paraskevi; Konstantopoulou, Irene; Grivas, Anastasios; Panopoulos, Christos; Dimitrakakis, Constantine; Kassanos, Dimitrios; Loghis, Constantine; Bramis, Ioannis; Vlahos, Nikolaos; Yannoukakos, Drakoulis; Fostira, Florentia
2015-01-01
BRCA mutation carriers can benefit from targeted clinical interventions. On the other hand, families with evident aggregation of breast cancer (BC) cases and a BRCA-negative genetic test can still be considered as of elevated risk, since the underlying genetic factor remains unidentified. In the present study, we compared clinical and demographic characteristics between BRCA1 mutation carriers (BRCA1mut) and non-carriers (non-BRCA1) in a Greek group of BC patients (n=321). Data were collected and analyzed from 321 women with BC, with 131 patients screened for pathogenic mutations in the high-penetrant genes BRCA1 and BRCA2. Collected data included demographics, pedigrees, tumor histopathology and immunohistochemistry findings. In BRCA1mut patients, their mothers and grand- mothers were diagnosed at a younger age compared to non-BRCA1-carriers. Additionally, BRCA1mut patients were diagnosed with mainly estrogen receptor (ER) negative (p<0.001), Her-2 negative (p<0.05) and triple negative (p<0.01) tumors. The youngest generation was diagnosed with familial breast cancer (FBC) 9.7 years earlier than their mothers (p<0.001). Age at BC diagnosis negatively correlated with the nuclear grade of breast tumors (r=-0.3, p<0.05). Among parous individuals, the number of full-term pregnancies significantly correlated with the age at BC onset (r=0.19, p<0.05). Despite their similarities, FBC cases with identified BRCA1 mutations exhibit a clearly distinct profile. We have identified an anticipation effect in FBC patients, with significantly reduced age at diagnosis in younger generations. Increased parity seems to prevent early BC onset. This is the first study comparing clinical and demographic characteristics of FBC BRCA1mut and non-carriers in a Greek cohort.
van Meijel, Els P M; Gigengack, Maj R; Verlinden, Eva; Opmeer, Brent C; Heij, Hugo A; Goslings, J Carel; Bloemers, Frank W; Luitse, Jan S K; Boer, Frits; Grootenhuis, Martha A; Lindauer, Ramón J L
2015-05-12
Children and their parents are at risk of posttraumatic stress disorder (PTSD) following injury due to pediatric accidental trauma. Screening could help predict those at greatest risk and provide an opportunity for monitoring so that early intervention may be provided. The purpose of this study was to evaluate the Screening Tool for Early Predictors of Posttraumatic Stress Disorder (STEPP) in a mixed-trauma sample in a non-English speaking country (the Netherlands). Children aged 8-18 and one of their parents were recruited in two academic level I trauma centers. The STEPP was assessed in 161 children (mean age 13.9 years) and 156 parents within one week of the accident. Three months later, clinical diagnoses and symptoms of PTSD were assessed in 147 children and 135 parents. We used the Anxiety Disorders Interview Schedule for DSM-IV - Child and Parent version, the Children's Revised Impact of Event Scale and the Impact of Event Scale-Revised. Receiver Operating Characteristic analyses were performed to estimate the Areas Under the Curve as a measure of performance and to determine the optimal cut-off score in our sample. Sensitivity, specificity, positive and negative predictive values were calculated. The aim was to maximize both sensitivity and negative predictive values. PTSD was diagnosed in 12% of the children; 10% of their parents scored above the cut-off point for PTSD. At the originally recommended cut-off scores (4 for children, 3 for parents), the sensitivity in our sample was 41% for children and 54% for parents. Negative predictive values were 92% for both groups. Adjusting the cut-off scores to 2 improved sensitivity to 82% for children and 92% for parents, with negative predictive values of 92% and 96%, respectively. With adjusted cut-off scores, the STEPP performed well: 82% of the children and 92% of the parents with a subsequent positive diagnosis were identified correctly. Special attention in the screening procedure is required because of a high rate of false positives. The STEPP appears to be a valid and useful instrument that can be used in the Netherlands as a first screening method in stepped psychotrauma care following accidents.
Landsbergen, K M; Prins, J B; Brunner, H G; van Duijvendijk, P; Nagengast, F M; van Krieken, J H; Ligtenberg, M; Hoogerbrugge, N
2012-06-01
According to the Dutch Guideline on Hereditary Colorectal Cancer published in 2008, patients with recently diagnosed colorectal cancer (CRC) should undergo microsatellite instability (MSI) testing by a pathologist immediately after tumour resection if they are younger than 50 years, or if a second CRC has been diagnosed before the age of 70 years, owing to the high risk of Lynch syndrome (MIPA). The aim of the present MIPAPS study was to investigate general distress and cancer-specific distress following MSI testing. From March 2007 to September 2009, 400 patients who had been tested for MSI after newly diagnosed CRC were recruited from 30 Dutch hospitals. Levels of general distress (SCL-90) and cancer-specific distress (IES) were assessed immediately after MSI result disclosure (T1) and 6 months later (T2). Response rates were 23/77 (30%) in the MSI-positive patients and 58/323 (18%) in the MSI-negative patients. Levels of general distress and cancer-specific distress were moderate. In the MSI-positive group, 27% of the patients had high general distress at T1 versus 18% at T2 (p = 0.5), whereas in the MSI-negative group, these percentage were 14 and 18% (p = 0.6), respectively. At T1 and T2, cancer-specific distress rates in the MSI-positive group and MSI-negative group were 39 versus 27% (p = 0.3) and 38 versus 36% (p = 1.0), respectively. High levels of general distress were correlated with female gender, low social support and high perceived cancer risk. Moderate levels of distress were observed after MSI testing, similar to those found in other patients diagnosed with CRC. Immediately after result disclosure, high cancer-specific distress was observed in 40% of the MSI-positive patients.
Tageja, Nishant; Korde, Neha; Kazandjian, Dickran; Panch, Sandhya; Manasanch, Elisabet; Bhutani, Manisha; Kwok, Mary; Mailankody, Sham; Yuan, Constance; Stetler-Stevenson, Maryalice; Leitman, Susan F; Sportes, Claude; Landgren, Ola
2018-05-04
Still, many physicians give 4 cycles of combination therapy to multiple myeloma patients prior to collection of stem cells for autologous bone marrow transplant. This tradition originates from older doxorubicin-containing regiments which limited the number of cycles due to cumulative cardiotoxicity. Using older regiments, most patients had residual myeloma cells in their autologous stem-cell grafts during collection. Emerging data show that newly diagnosed multiple myeloma patients treated with modern carfilzomib/lenalidomide/dexamethasone (KRd) therapy, on average, take 6 cycles until reaching minimal residual disease (MRD) negativity. We assessed newly diagnosed patients treated with KRd focusing MRD status both in the individual patient's bone marrow, and the corresponding autologous hematopoietic progenitor cell grafts during collection. Per protocol, stem-cell collection was allowed after 4 to 8 cycles of KRd. We found similar stem-cell yield independent of the number of cycles of KRd. At stem-cell collection, 11/30 patients (36.6%) were MRD negative in their bone marrow; all 11 patients had MRD negative hematopoietic progenitor cell grafts. Furthermore, 18/19 patients who were MRD positive in their bone marrows also had MRD negative hematopoietic progenitor cell grafts. These observations support 6 cycles of KRd as an efficacious and safe induction strategy prior to stem-cell collection.
Lobo, João; Henrique, Rui; Monteiro, Paula; Lobo, Cláudia
2017-04-01
Anaplastic large cell lymphoma is an aggressive T-cell neoplasm. It rarely involves the urinary bladder, with just twelve cases reported thus far and only one being ALK-negative. Immunophenotyping (particularly for ALK) is mandatory, both for prognostic and therapeutic reasons. Herein, we report the case of a patient with an ALK-negative anaplastic large cell lymphoma involving the bladder which was diagnosed and fully characterized by immunocytochemistry in urine cytology. The patient underwent a cystoscopy and the urine sample disclosed tumor diathesis background and aggregates of atypical cells, with evidence of multinucleation and mitotic figures. Immunocytochemistry revealed strong membrane/Golgi positivity for CD30 and negativity for ALK. The patient was submitted to transurethral resection for therapeutic purposes, which confirmed the diagnosis. To the best of our knowledge, this represents only the third case of anaplastic large cell lymphoma with bladder involvement diagnosed in urine cytology and the very first with diagnostic findings allowing for immunophenotyping of the disease in a bladder wash. The present report reinforces the role of urine cytology as a suitable method for establishing an earlier diagnosis and characterization of the disease, avoiding submitting patients to invasive procedures like transurethral resections. Diagn. Cytopathol. 2017;45:354-358. © 2016 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Bell, David J; Dacombe, Russell; Graham, Stephen M; Hicks, Alexander; Cohen, Danielle; Chikaonda, Tarsizio; French, Neil; Molyneux, Malcolm E; Zijlstra, Ed E; Squire, S Bertel; Gordon, Stephen B
2010-01-01
Setting Detection of smear-positive pulmonary tuberculosis (PTB) cases is vital for tuberculosis control. Methods to augment sputum collection are available but their additional benefit is uncertain in resource-limited settings. Objective To compare the diagnostic yields using five methods to obtain sputum from adults diagnosed with smear-negative PTB in Malawi. Design Self-expectorated sputum was collected under supervision for microscopy and mycobacterial culture in the study laboratory. Confirmed smear-negative patients, provided physiotherapy-assisted sputum and induced sputum followed, the next morning, by gastric washing and bronchoalveolar-lavage samples. Results 150 patients, diagnosed with smear-negative PTB by the hospital service, were screened. 39 (26%) were smear-positive from supervised self-expectorated sputum examined in the study laboratory. The remaining 111 confirmed smear-negative patients were enrolled; 89% were HIV positive. Seven additional smear-positive cases were diagnosed using the augmented sputum collection techniques. No differences were observed in the numbers of cases detected using the different methods. 44 (95.6%) of the 46 smear-positive cases could be detected from self-expectorated and physiotherapy-assisted samples Conclusions For countries like Malawi, the best use of limited resources to detect smear-positive PTB cases would be to improve the quality of self-expectorated sputum collection and microscopy. The additional diagnostic yield using bronchoalveolar-lavage after induced sputum is limited. PMID:19105886
Rahal, M; Kervaire, B; Villard, J; Tiercy, J-M
2008-03-01
Human leukocyte antigen (HLA) typing by polymerase chain reaction-sequence-specific oligonucleotide (PCR-SSO) hybridization on solid phase (microbead assay) or polymerase chain reaction-sequence-specific primers (PCR-SSP) requires interpretation softwares to detect all possible allele combinations. These programs propose allele calls by taking into account false-positive or false-negative signal(s). The laboratory has the option to validate typing results in the presence of strongly cross-reacting or apparent false-negative signals. Alternatively, these seemingly aberrant signals may disclose novel variants. We report here four new HLA-B (B*5620 and B*5716) and HLA-DRB1 alleles (DRB1*110107 and DRB1*1474) that were detected by apparent false-negative or -positive hybridization or amplification patterns, and ultimately resolved by sequencing. To avoid allele misassignments, a comprehensive evaluation of acquired data as documented in a quality assurance system is therefore required to confirm unambiguous typing interpretation.
Beard, Renée L; Fetterman, David J; Wu, Bei; Bryant, Lucinda
2009-06-01
Most individuals with Alzheimer's are cared for in their homes by unpaid family members. Research on caregiving focuses disproportionally on costs of care, service utilization, and negative psychosocial outcomes. Few narrative accounts of Alzheimer's exist; those that do suffer similar pejorative framings and narrow foci. No studies that we are aware of examine the health beliefs of diagnosed individuals and support persons, or their attitudes about brain health. This research reports perceptions of "aging well" held by those most intimately acquainted with Alzheimer's. Diagnosed individuals and their support persons (N = 85) were enrolled into 14 focus groups. Grounded theory methods were used to collect, code, and analyze textual interview data into overarching themes. Respondents found physical and mental health, social activity, independence, and happiness integral to aging well. An acceptance of various limitations was also deemed crucial. Support persons placed more emphasis on lifestyle factors and memory loss as potential obstacles. Diagnosed respondents defined memory loss in less medicalized terms, whereas support persons labeled it Alzheimer's and negatively characterized those affected. Both groups warned against discussing "prevention" of dementia: Diagnosed individuals noted the implication of "aging poorly" and support persons cautioned against blaming diagnosed individuals. These findings can be used to encourage positive health beliefs and behaviors tailored to the needs of diagnosed seniors and their families, to help practitioners and researchers identify and become sensitive to differences between and among older adults, and to further advance the utility of narrative accounts for informing health interventions and education efforts.
Kimmitt, Patrick T; Kirby, Andrew; Perera, Nelun; Nicholson, Karl G; Schober, Paul C; Rajakumar, Kumar; Chapman, Cordelia A
2008-01-01
Sexually transmitted infections (STIs) are an increasingly common and important cause of a fever in a returning traveler. Systemic complications of STIs, human immunodeficiency virus seroconversion illness, and secondary syphilis are diagnoses that can easily be missed. We present a case of culture-negative disseminated gonococcal infection presenting with fever, malaise, polyarthralgia, arthritis, and a rash that developed following orogenital contact and was diagnosed using real-time polymerase chain reaction. This technology has major potential to improve the speed and sensitivity of diagnosis and consequent management of patients with this syndrome.
Diagnosing Invasive Candidiasis.
Clancy, Cornelius J; Nguyen, M Hong
2018-05-01
Cultures are negative in ∼50% of invasive candidiasis. Data are emerging for the performance of nonculture tests such as mannan/antimannan, Candida albicans germ tube antibody, 1,3-β-d-glucan, PCR, and the T2Candida panel in diagnosing both candidemia and deep-seated candidiasis. In most settings, positive predictive values of nonculture test are low, and negative predictive values are high. For tests to be useful, clinicians must understand the pretest likelihood of invasive candidiasis and test performance for the most common disease manifestation in a given patient. This paper reviews nonculture Candida diagnostics and discusses how they might be used effectively in patient care. Copyright © 2018 American Society for Microbiology.
Dehon, Hedwige; Larøi, Frank; Van der Linden, Martial
2010-10-01
This study examined the influence of emotional valence on the production of DRM false memories (Roediger & McDermott, 1995). Participants were presented with neutral, positive, or negative DRM lists for a later recognition (Experiment 1) or recall (Experiment 2) test. In both experiments, confidence and recollective experience (i.e., "Remember-Know" judgments; Tulving, 1985) were also assessed. Results consistently showed that, compared with neutral lists, affective lists induced more false recognition and recall of nonpresented critical lures. Moreover, although confidence ratings did not differ between the false remembering from the different kinds of lists, "Remember" responses were more often associated with negative than positive and neutral false remembering of the critical lures. In contrast, positive false remembering of the critical lures was more often associated with "Know" responses. These results are discussed in light of the Paradoxical Negative Emotion (PNE) hypothesis (Porter, Taylor, & ten Bricke, 2008). (PsycINFO Database Record (c) 2010 APA, all rights reserved).
The role of attention at retrieval on the false recognition of negative emotional DRM lists.
Shah, Datin; Knott, Lauren M
2018-02-01
This study examined the role of attention at retrieval on the false recognition of emotional items using the Deese-Roediger-McDermott (DRM) paradigm. Previous research has shown that divided attention at test increases false remember judgements for neutral critical lures. However, no research has yet directly assessed emotional false memories when attention is manipulated at retrieval. To examine this, participants studied negative (low in valence and high in arousal) and neutral DRM lists and completed recognition tests under conditions of full and divided attention. Results revealed that divided attention at retrieval increased false remember judgements for all critical lures compared to retrieval under full attention, but in both retrieval conditions, false memories were greater for negative compared to neutral stimuli. We believe that this is due to reliance on a more easily accessible (meaning of the word) but less diagnostic form of source monitoring, amplified under conditions of divided attention.
Introducing Bayesian thinking to high-throughput screening for false-negative rate estimation.
Wei, Xin; Gao, Lin; Zhang, Xiaolei; Qian, Hong; Rowan, Karen; Mark, David; Peng, Zhengwei; Huang, Kuo-Sen
2013-10-01
High-throughput screening (HTS) has been widely used to identify active compounds (hits) that bind to biological targets. Because of cost concerns, the comprehensive screening of millions of compounds is typically conducted without replication. Real hits that fail to exhibit measurable activity in the primary screen due to random experimental errors will be lost as false-negatives. Conceivably, the projected false-negative rate is a parameter that reflects screening quality. Furthermore, it can be used to guide the selection of optimal numbers of compounds for hit confirmation. Therefore, a method that predicts false-negative rates from the primary screening data is extremely valuable. In this article, we describe the implementation of a pilot screen on a representative fraction (1%) of the screening library in order to obtain information about assay variability as well as a preliminary hit activity distribution profile. Using this training data set, we then developed an algorithm based on Bayesian logic and Monte Carlo simulation to estimate the number of true active compounds and potential missed hits from the full library screen. We have applied this strategy to five screening projects. The results demonstrate that this method produces useful predictions on the numbers of false negatives.
Knaster, Peter; Estlander, Ann-Mari; Karlsson, Hasse; Kaprio, Jaakko; Kalso, Eija
2016-01-01
Diagnosing depression in chronic pain is challenging due to overlapping somatic symptoms. In questionnaires, such as the Beck Depression Inventory (BDI), responses may be influenced more by pain than by the severity of depression. In addition, previous studies have suggested that symptoms of negative self-image, a key element in depression, are uncommon in chronic pain-related depression. The object of this study is to assess the relationship of the somatic and cognitive-emotional items of BDI with the diagnosis of depression, pain intensity, and disability. One hundred consecutive chronic pain patients completed the Structured Clinical Interview for DSM Disorders (SCID) for the diagnosis of major depressive disorder (MDD) according to DSM-IV. Two subscales of BDI (negative view of self and somatic-physical function) were created according to the factor model presented by Morley. In the regression analysis, the somatic-physical function factor associated with MDD, while the negative view of self factor did not. Patients with MDD had higher scores in several of the BDI items when analysed separately. Insomnia and weight loss were not dependent on the depression diagnosis. The relatively small sample size and the selected patient sample limit the generalisability of the results. Somatic symptoms of depression are also common in chronic pain and should not be excluded when diagnosing depression in pain patients. Regardless of the assessment method, diagnosing depression in chronic pain remains a challenge and requires careful interpretation of symptoms.
Kufa, Tendesayi; Lane, Tim; Manyuchi, Albert; Singh, Beverley; Isdahl, Zachary; Osmand, Thomas; Grasso, Mike; Struthers, Helen; McIntyre, James; Chipeta, Zawadi; Puren, Adrian
2017-01-01
Abstract We describe the accuracy of serial rapid HIV testing among men who have sex with men (MSM) in South Africa and discuss the implications for HIV testing and prevention. This was a cross-sectional survey conducted at five stand-alone facilities from five provinces. Demographic, behavioral, and clinical data were collected. Dried blood spots were obtained for HIV-related testing. Participants were offered rapid HIV testing using 2 rapid diagnostic tests (RDTs) in series. In the laboratory, reference HIV testing was conducted using a third-generation enzyme immunoassay (EIA) and a fourth-generation EIA as confirmatory. Accuracy, sensitivity, specificity, positive predictive value, negative predictive value, false-positive, and false-negative rates were determined. Between August 2015 and July 2016, 2503 participants were enrolled. Of these, 2343 were tested by RDT on site with a further 2137 (91.2%) having definitive results on both RDT and EIA. Sensitivity, specificity, positive predictive value, negative predictive value, false-positive rates, and false-negative rates were 92.6% [95% confidence interval (95% CI) 89.6–94.8], 99.4% (95% CI 98.9–99.7), 97.4% (95% CI 95.2–98.6), 98.3% (95% CI 97.6–98.8), 0.6% (95% CI 0.3–1.1), and 7.4% (95% CI 5.2–10.4), respectively. False negatives were similar to true positives with respect to virological profiles. Overall accuracy of the RDT algorithm was high, but sensitivity was lower than expected. Post-HIV test counseling should include discussions of possible false-negative results and the need for retesting among HIV negatives. PMID:28700474
Emotions and false memories: valence or arousal?
Corson, Yves; Verrier, Nadège
2007-03-01
The effects of mood on false memories have not been studied systematically until recently. Some results seem to indicate that negative mood may reduce false recall and thus suggest an influence of emotional valence on false memory. The present research tested the effects of both valence and arousal on recall and recognition and indicates that the effect is actually due to arousal. In fact, whether participants' mood is positive, negative, or neutral, false memories are significantly more frequent under conditions of high arousal than under conditions of low arousal.
Griffey, Richard T; Trent, Caleb J; Bavolek, Rebecca A; Keeperman, Jacob B; Sampson, Christopher; Poirier, Robert F
2013-01-01
Failure to detect pregnancy in the emergency department (ED) can have important consequences. Urine human chorionic gonadotropin (uhCG) point-of-care (POC) assays are valued for rapidly detecting early pregnancy with high sensitivity. However, under certain conditions, POC uhCG tests can fail to detect pregnancy. In investigating a series of late first-trimester false-negative pregnancy tests in our ED, a novel and distinct causative phenomenon was recently elucidated in our institution. We discuss uhCG POC tests, review our false-negative rate, and describe mechanisms for false negatives and potential remedies. The false-negative POC uhCG rate is very low, but in the setting of a large volume of tests, the numbers are worth consideration. In positive uhCG POC tests, free and fixed antibodies bind hCG to form a "sandwich"; hCG is present in several variant forms that change in their concentrations at different stages of pregnancy. When in excess, intact hCG can saturate the antibodies, preventing sandwich formation (hook effect phenomenon). Some assays may include an antibody that does not recognize certain variants present in later stages of pregnancy. When this variant is in excess, it can bind one antibody avidly and the other not at all, resulting in a false-negative test (hook-like phenomenon). In both situations, dilution is key to an accurate test. Manufacturers should consider that uhCG tests are routinely used at many stages of pregnancy. Characterizing uhCG variants recognized by their tests and eliminating lot-to-lot variability may help improve uhCG test performance. Clinicians need to be aware of and familiarize themselves with the limitations of the specific type of uhCG POC tests used in their practice, recognizing that under certain circumstances, false-negative tests can occur. Copyright © 2013 Elsevier Inc. All rights reserved.
Ekholm, E; Gottsäter, A; Dahlin, L B; Sundkvist, G
2012-02-01
Both type 1 and type 2 diabetes are considered to be associated with different degrees of progressive beta cell damage. However, few long-term studies have been made. Our aim was to study the clinical course of 20 years of diabetes disease, including diabetes progression, comorbidity, and mortality in a prospectively studied cohort of consecutively diagnosed diabetic patients. Among all 233 patients diagnosed with diabetes during 1985-1987 in Malmö, Sweden, 50 of 118 surviving patients were followed-up after 20 years. The age at diagnose was 42.3 ± 23.1 and 57.5 ± 13.6 years for antibody-positive and antibody-negative patients, respectively. HbA1c and plasma lipids were analyzed with regard to metabolic control. Islet antibody-negative patients at diagnosis had highly preserved C-peptide levels after 20 years in contrast to antibody-positive patients (antibody negative: C-peptide 0 years 0.78 ± 0.47 and 20 years 0.70 ± 0.46 (nmol/l), P = 0.51 and antibody positive: C-peptide 0 years 0.33 ± 0.35 and 20 years 0.10 ± 0.18; P < 0.001. Islet antibodies but not age, BMI, or C-peptide at diagnosis were predictors of C-peptide levels at 20 years when analyzed by logistic regression (P < 0.05). HbA1c did not differ between the groups after 20 years. The 20-year mortality was higher among antibody-negative patients, dependent on the higher age at diagnosis in this group (number of deaths: antibody positive: 18 of 56 vs. antibody negative: 109 of 188, P < 0.001). Of the deceased, 79% had died from diseases or complications that may be associated with diabetes. We found no progressive beta cell damage in autoantibody-negative diabetes at a 20-year follow-up of the clinical course of diabetes.
Effects of depressive disorder on false memory for emotional information.
Yeh, Zai-Ting; Hua, Mau-Sun
2009-01-01
This study explored with a false memory paradigm whether (1) depressed patients revealed more false memories and (2) whether more negative false than positive false recognition existed in subjects with depressive disorders. Thirty-two patients suffering from a major depressive episode (DSM-IV criteria), and 30 age- and education-matched normal control subjects participated in this study. After the presentation of a list of positive, negative, and neutral association items in the learning phase, subjects were asked to give a yes/no response in the recognition phase. They were also asked to rate 81 recognition items with emotional valence scores. The results revealed more negative false memories in the clinical depression group than in the normal control group; however, we did not find more negative false memories than positive ones in patients. When compared with the normal group, a more conservative response criterion for positive items was evident in patient groups. It was also found that when compared with the normal group, the subjects in the depression group perceived the positive items as less positive. On the basis of present results, it is suggested that depressed subjects judged the emotional information with criteria different from normal individuals, and patients' emotional memory intensity is attenuated by their mood.
First rank symptoms for schizophrenia.
Soares-Weiser, Karla; Maayan, Nicola; Bergman, Hanna; Davenport, Clare; Kirkham, Amanda J; Grabowski, Sarah; Adams, Clive E
2015-01-25
Early and accurate diagnosis and treatment of schizophrenia may have long-term advantages for the patient; the longer psychosis goes untreated the more severe the repercussions for relapse and recovery. If the correct diagnosis is not schizophrenia, but another psychotic disorder with some symptoms similar to schizophrenia, appropriate treatment might be delayed, with possible severe repercussions for the person involved and their family. There is widespread uncertainty about the diagnostic accuracy of First Rank Symptoms (FRS); we examined whether they are a useful diagnostic tool to differentiate schizophrenia from other psychotic disorders. To determine the diagnostic accuracy of one or multiple FRS for diagnosing schizophrenia, verified by clinical history and examination by a qualified professional (e.g. psychiatrists, nurses, social workers), with or without the use of operational criteria and checklists, in people thought to have non-organic psychotic symptoms. We conducted searches in MEDLINE, EMBASE, and PsycInfo using OvidSP in April, June, July 2011 and December 2012. We also searched MEDION in December 2013. We selected studies that consecutively enrolled or randomly selected adults and adolescents with symptoms of psychosis, and assessed the diagnostic accuracy of FRS for schizophrenia compared to history and clinical examination performed by a qualified professional, which may or may not involve the use of symptom checklists or based on operational criteria such as ICD and DSM. Two review authors independently screened all references for inclusion. Risk of bias in included studies were assessed using the QUADAS-2 instrument. We recorded the number of true positives (TP), true negatives (TN), false positives (FP), and false negatives (FN) for constructing a 2 x 2 table for each study or derived 2 x 2 data from reported summary statistics such as sensitivity, specificity, and/or likelihood ratios. We included 21 studies with a total of 6253 participants (5515 were included in the analysis). Studies were conducted from 1974 to 2011, with 80% of the studies conducted in the 1970's, 1980's or 1990's. Most studies did not report study methods sufficiently and many had high applicability concerns. In 20 studies, FRS differentiated schizophrenia from all other diagnoses with a sensitivity of 57% (50.4% to 63.3%), and a specificity of 81.4% (74% to 87.1%) In seven studies, FRS differentiated schizophrenia from non-psychotic mental health disorders with a sensitivity of 61.8% (51.7% to 71%) and a specificity of 94.1% (88% to 97.2%). In sixteen studies, FRS differentiated schizophrenia from other types of psychosis with a sensitivity of 58% (50.3% to 65.3%) and a specificity of 74.7% (65.2% to 82.3%). The synthesis of old studies of limited quality in this review indicates that FRS correctly identifies people with schizophrenia 75% to 95% of the time. The use of FRS to diagnose schizophrenia in triage will incorrectly diagnose around five to 19 people in every 100 who have FRS as having schizophrenia and specialists will not agree with this diagnosis. These people will still merit specialist assessment and help due to the severity of disturbance in their behaviour and mental state. Again, with a sensitivity of FRS of 60%, reliance on FRS to diagnose schizophrenia in triage will not correctly diagnose around 40% of people that specialists will consider to have schizophrenia. Some of these people may experience a delay in getting appropriate treatment. Others, whom specialists will consider to have schizophrenia, could be prematurely discharged from care, if triage relies on the presence of FRS to diagnose schizophrenia. Empathetic, considerate use of FRS as a diagnostic aid - with known limitations - should avoid a good proportion of these errors.We hope that newer tests - to be included in future Cochrane reviews - will show better results. However, symptoms of first rank can still be helpful where newer tests are not available - a situation which applies to the initial screening of most people with suspected schizophrenia. FRS remain a simple, quick and useful clinical indicator for an illness of enormous clinical variability.
Srisukho, Sasivimol; Tongsong, Theera; Srisupundit, Kasemsri
2014-10-01
To determine the degree of adherence to guidelines on the diagnosis of cephalopelvic disproportion (CPD) in Maharaj Nakorn Chiang Mai Hospital. The database ofpregnant women who underwent cesarean delivery due to CPD between 2010 and 2012 was reviewed The degree of adherence to guidelines on the CPD diagnosis was recorded The guidelines were from Royal Thai College of Obstetricians and Gynecologists (RTCOG) and the American Congress of Obstetricians and Gynecologists (ACOG) as gold standard criteria for CPD diagnosis. Four hundred sixty four pregnant women diagnosed as CPD were recruited. The adherence to guidelines either RTCOG or ACOG criteria was 80.4%. Of 91 cases that had incomplete criteria to diagnose CPD, 25 cases (27.5%) had been suspected offetal macrosomia and CPD was diagnosed during latent phase of labor Unfortunately, 76% of these fetuses had birth weight less than 4000 grams, which were unlikely to be macrosomia. The adherence to guidelines on the diagnosis of CPD was 80.4%. Almost one-third of the cases that had no adherence were false diagnosed of fetal macrosomia. Therefore, the strategy of accurate fetal weigh estimation may reduce unnecessary cesarean section from false diagnosis of CPD.
Tetteh, Ato Kwamena; Agyarko, Edward
2017-01-01
Screening results of 488 pregnant women aged 15-44 years whose blood samples had been tested on-site, using First Response® HIV 1/2, and confirmed with INNO-LIA™ HIV I/II Score were used. Of this total, 178 were reactive (HIV I, 154; HIV II, 2; and HIV I and HIV II, 22). Of the 154 HIV I-reactive samples, 104 were confirmed to be HIV I-positive and 2 were confirmed to be HIV II-positive, while 48 were confirmed to be negative [false positive rate = 17.44% (13.56-21.32)]. The two HIV II samples submitted were confirmed to be negative with the confirmatory test. For the 22 HIV I and HIV II samples, 7 were confirmed to be HIV I-positive and 1 was confirmed to be HIV I- and HIV II-positive, while 14 were confirmed to be negative. Of the 310 nonreactive samples, 6 were confirmed to be HIV I-positive and 1 was confirmed to be HIV II-positive [false negative rate = 5.79% (1.63-8.38)], while 303 were negative. False negative outcomes will remain unconfirmed, with no management options for the client. False negative rate of 5.79% requires attention, as its resultant implications on control of HIV/AIDS could be dire.
Belaz, Sorya; Gangneux, Jean-Pierre; Dupretz, Peggy; Guiguen, Claude
2015-01-01
This study aimed to evaluate the repeated sequence REP-529 compared to that of the B1 gene in the molecular diagnosis of toxoplasmosis by quantitative PCR (qPCR) in routine diagnosis. Over a 10-year period (2003 to 2013), all patients prospectively diagnosed with a positive REP-529 qPCR result for toxoplasmosis were included. All DNA samples (76 samples from 56 patients) were simultaneously tested using the two qPCR methods (REP-529 and B1). The mean cycle threshold (CT) obtained with the B1 qPCR was significantly higher (+4.71 cycles) than that obtained with REP-529 qPCR (P < 0.0001). Thirty-one out of 69 extracts (45.6%) positive with REP-529 qPCR were not amplified with the B1 qPCR (relative sensitivity of 54.4% compared to that with REP-529), yielding false-negative results with 15/28 placenta, 5 cord blood, 2 amniotic fluid, 4 cerebrospinal fluid, 1 aqueous humor, 2 lymph node puncture, and 1 abortion product sample. This defect in sensitivity would have left 20/56 patients undiagnosed, distributed as follows: 12/40 congenital toxoplasmosis, 4/5 cerebral toxoplasmosis, 2/8 patients with retinochoroiditis, and 2 patients with chronic lymphadenopathy. This poor performance of B1 qPCR might be related to low parasite loads, since the mean Toxoplasma quantification in extracts with B1 false-negative results was 0.4 parasite/reaction. These results clearly show the superiority of the REP-529 sequence in the diagnosis of toxoplasmosis by PCR and suggest that this target should be adopted as part of the standardization of the PCR assay. PMID:25653416
Belaz, Sorya; Gangneux, Jean-Pierre; Dupretz, Peggy; Guiguen, Claude; Robert-Gangneux, Florence
2015-04-01
This study aimed to evaluate the repeated sequence REP-529 compared to that of the B1 gene in the molecular diagnosis of toxoplasmosis by quantitative PCR (qPCR) in routine diagnosis. Over a 10-year period (2003 to 2013), all patients prospectively diagnosed with a positive REP-529 qPCR result for toxoplasmosis were included. All DNA samples (76 samples from 56 patients) were simultaneously tested using the two qPCR methods (REP-529 and B1). The mean cycle threshold (CT) obtained with the B1 qPCR was significantly higher (+4.71 cycles) than that obtained with REP-529 qPCR (P<0.0001). Thirty-one out of 69 extracts (45.6%) positive with REP-529 qPCR were not amplified with the B1 qPCR (relative sensitivity of 54.4% compared to that with REP-529), yielding false-negative results with 15/28 placenta, 5 cord blood, 2 amniotic fluid, 4 cerebrospinal fluid, 1 aqueous humor, 2 lymph node puncture, and 1 abortion product sample. This defect in sensitivity would have left 20/56 patients undiagnosed, distributed as follows: 12/40 congenital toxoplasmosis, 4/5 cerebral toxoplasmosis, 2/8 patients with retinochoroiditis, and 2 patients with chronic lymphadenopathy. This poor performance of B1 qPCR might be related to low parasite loads, since the mean Toxoplasma quantification in extracts with B1 false-negative results was 0.4 parasite/reaction. These results clearly show the superiority of the REP-529 sequence in the diagnosis of toxoplasmosis by PCR and suggest that this target should be adopted as part of the standardization of the PCR assay. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Koplay, M; Kizilca, O; Cimen, D; Sivri, M; Erdogan, H; Guvenc, O; Oc, M; Oran, B
2016-11-01
The goal of this study was to investigate the radiation dose and diagnostic efficacy of cardiac computed tomography angiography (CCTA) using prospective ECG-gated high-pitch dual-source computed tomography (DSCT) in the diagnosis of congenital cardiovascular abnormalities in pediatric population. One hundred five pediatric patients who were clinically diagnosed with congenital heart disease with suspected extracardiac vascular abnormalities were included in the study. All CCTAs were performed on a 128×2-section DSCT scanner. CCTA findings were compared with surgical and/or conventional cardiac angiography findings. Dose-length product (DLP) and effective doses (ED) were calculated for each patient. Patients were divided into 4 groups by age, and ED and DLP values were compared among groups. The image quality was evaluated using a five-point scale. CCTA showed 173 abnormalities in 105 patients. There were 2 patients with false positive and 3 with false negative findings. The sensitivity and specificity of CCTA were 98.3% and 99.9%, respectively. The positive predictive value and negative predictive value of CCT were 98.9% and 99.9%, respectively. The average DLP and ED values were 15.6±9.6 (SD) mGy.cm and 0.34±0.10 (SD) mSv, respectively. The mean image quality score was 4.8±0.5 (SD) in all patients. The inter-observer agreement for the image quality scores was good (κ=0.80). CCTA is an excellent imaging modality for evaluation of cardiovascular abnormalities and provides excellent image quality with very low radiation exposure when low-dose prospective ECG-triggered high-pitch DSCT is used. Copyright © 2016 Editions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.
Bordelon, Hali; Ricks, Keersten M.; Pask, Megan E.; Russ, Patricia K.; Solinas, Francesca; Baglia, Mark L.; Short, Philip A.; Nel, Andrew; Blackburn, Jonathan; Dheda, Keertan; Zamudio, Carlos; Cáceres, Tatiana; Wright, David W.; Haselton, Frederick R.; Pettit, April C.
2017-01-01
Urine samples are increasingly used for diagnosing infections including Escherichia coli, Ebola virus, and Zika virus. However, extraction and concentration of nucleic acid biomarkers from urine is necessary for many molecular detection strategies such as polymerase chain reaction (PCR). Since urine samples typically have large volumes with dilute biomarker concentrations making them prone to false negatives, another impediment for urine-based diagnostics is the establishment of appropriate controls particularly to rule out false negatives. In this study, a mouse glyceraldehyde 3-phosphate dehydrogenase (GAPDH) DNA target was added to retrospectively collected urine samples from tuberculosis (TB)-infected and TB-uninfected patients to indicate extraction of intact DNA and removal of PCR inhibitors from urine samples. We tested this design on surrogate urine samples, retrospective 1 milliliter (mL) urine samples from patients in Lima, Peru and retrospective 5 mL urine samples from patients in Cape Town, South Africa. Extraction/PCR control DNA was detectable in 97% of clinical samples with no statistically significant differences among groups. Despite the inclusion of this control, there was no difference in the amount of TB IS6110 Tr-DNA detected between TB-infected and TB-uninfected groups except for samples from known HIV-infected patients. We found a increase in TB IS6110 Tr-DNA between TB/HIV co-infected patients compared to TB-uninfected/HIV-infected patients (N=18, p=0.037). The inclusion of an extraction/PCR control DNA to indicate successful DNA extraction and removal of PCR inhibitors should be easily adaptable as a sample preparation control for other acellular sample types. PMID:28285168
Bordelon, Hali; Ricks, Keersten M; Pask, Megan E; Russ, Patricia K; Solinas, Francesca; Baglia, Mark L; Short, Philip A; Nel, Andrew; Blackburn, Jonathan; Dheda, Keertan; Zamudio, Carlos; Cáceres, Tatiana; Wright, David W; Haselton, Frederick R; Pettit, April C
2017-05-01
Urine samples are increasingly used for diagnosing infections including Escherichia coli, Ebola virus, and Zika virus. However, extraction and concentration of nucleic acid biomarkers from urine is necessary for many molecular detection strategies such as polymerase chain reaction (PCR). Since urine samples typically have large volumes with dilute biomarker concentrations making them prone to false negatives, another impediment for urine-based diagnostics is the establishment of appropriate controls particularly to rule out false negatives. In this study, a mouse glyceraldehyde 3-phosphate dehydrogenase (GAPDH) DNA target was added to retrospectively collected urine samples from tuberculosis (TB)-infected and TB-uninfected patients to indicate extraction of intact DNA and removal of PCR inhibitors from urine samples. We tested this design on surrogate urine samples, retrospective 1milliliter (mL) urine samples from patients in Lima, Peru and retrospective 5mL urine samples from patients in Cape Town, South Africa. Extraction/PCR control DNA was detectable in 97% of clinical samples with no statistically significant differences among groups. Despite the inclusion of this control, there was no difference in the amount of TB IS6110 Tr-DNA detected between TB-infected and TB-uninfected groups except for samples from known HIV-infected patients. We found an increase in TB IS6110 Tr-DNA between TB/HIV co-infected patients compared to TB-uninfected/HIV-infected patients (N=18, p=0.037). The inclusion of an extraction/PCR control DNA to indicate successful DNA extraction and removal of PCR inhibitors should be easily adaptable as a sample preparation control for other acellular sample types. Copyright © 2017 Elsevier B.V. All rights reserved.
Le Jeune, Florence Prigent; Dubois, François; Blond, Serge; Steinling, Marc
2006-04-01
In the follow-up of treated gliomas, CT and MRI can often not differentiate radionecrosis from recurrent tumor. The aim of this study was to assess the interest of functional imaging with (99m)Tc-MIBI SPECT in a large series of 201 examinations. MIBI SPECT were performed in 81 patients treated for brain gliomas. A MIBI uptake index was computed as the ratio of counts in the lesion to counts in the controlateral region. SPECT was compared to stereotactic biopsy in 14 cases, or in the others cases to imaging evolution or clinical course at 6 months after the last tomoscintigraphy Two hundred and one tomoscintigraphies were performed. One hundred and two scans were true positive, 82 scans were true negative. Six scans were false positive (corresponding to 3 patients): 2 patients with an inflammatory reaction after radiosurgery, 1 with no explanation up to now. Eleven scans were false negative (5 patients): 1 patient with a deep peri-ventricular lesion, 2 patients with no contrast enhancement on MRI, 2 patients with a temporal tumor. The sensitivity for tumor recurrence was 90%, specificity 91.5% and accuracy 90.5%. We studied separately low and high grade glioma: sensitivity for tumor recurrence was respectively 91% and 89%, specificity 100% and 83% and accuracy 95% and 87%. MIBI SPECT allowed the diagnose of anaplasic degenerence of low grade sometimes earlier than clinical (5 cases) or MRI signs (7 cases). Our results confirm the usefullness of MIBI SPECT in the follow-up of treated gliomas for the differential diagnosis between radiation necrosis and tumor recurrence.
Reck, Martin; Hagiwara, Koichi; Han, Baohui; Tjulandin, Sergei; Grohé, Christian; Yokoi, Takashi; Morabito, Alessandro; Novello, Silvia; Arriola, Edurne; Molinier, Olivier; McCormack, Rose; Ratcliffe, Marianne; Normanno, Nicola
2016-10-01
To offer patients with EGFR mutation-positive advanced NSCLC appropriate EGFR tyrosine kinase inhibitor treatment, mutation testing of tumor samples is required. However, tissue/cytologic samples are not always available or evaluable. The large, noninterventional diagnostic ASSESS study (NCT01785888) evaluated the utility of circulating free tumor-derived DNA (ctDNA) from plasma for EGFR mutation testing. ASSESS was conducted in 56 centers (in Europe and Japan). Eligible patients (with newly diagnosed locally advanced/metastatic treatment-naive advanced NSCLC) provided diagnostic tissue/cytologic and plasma samples. DNA extracted from tissue/cytologic samples was subjected to EGFR mutation testing using local practices; designated laboratories performed DNA extraction/mutation testing of blood samples. The primary end point was level of concordance of EGFR mutation status between matched tissue/cytologic and plasma samples. Of 1311 patients enrolled, 1288 were eligible. Concordance of mutation status in 1162 matched samples was 89% (sensitivity 46%, specificity 97%, positive predictive value 78%, and negative predictive value 90%). A group of 25 patients with apparent false-positive plasma results was overrepresented for cytologic samples, use of less sensitive tissue testing methodologies, and smoking habits associated with high EGFR mutation frequency, indicative of false-negative tumor results. In cases in which plasma and tumor samples were tested with identical highly sensitive methods, positive predictive value/sensitivity were generally improved. These real-world data suggest that ctDNA is a feasible sample for EGFR mutation analysis. It is important to conduct mutation testing of both tumor and plasma samples in specialized laboratories, using robust/sensitive methods to ensure that patients receive appropriate treatments that target the molecular features of their disease. Copyright © 2016 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.
Siddiqui, Ali A; Fein, Michael; Kowalski, Thomas E; Loren, David E; Eloubeidi, Mohamad A
2012-09-01
Prior studies have reported that the presence of prior biliary stent may interfere with EUS visualization of pancreatic tumors. We aimed to compare the influence of the biliary plastic and fully covered self-expanding metal stents (CSEMS) on the accuracy of EUS-FNA cytology in patients with solid pancreatic masses. We conducted a retrospective study evaluating 677 patients with solid pancreatic head/uncinate lesions and a previous biliary stent in whom EUS-FNA was performed. The patients were stratified into two groups: (1) those with a plastic stents and (2) those with CSEMS. Performance characteristics of EUS-FNA including the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were compared between the two groups. The frequency of obtaining an adequate cytology by EUS-FNA was similar in both the CSEMS group and the plastic stent group (97 vs. 97.1 % respectively; p = 1.0). The sensitivity, specificity, and accuracy of EUS-FNA was not significantly different between patients with CSEMS and plastic stents (96.8, 100, 100 % and 97.3, 98, 99.8 %, respectively). The negative predictive value for EUS-FNA was lower in the CSEMS group compared to the plastic stent group (66.6 vs. 78.1 % respectively; p = 0.42). There was one false-positive cytology in the plastic stent group compared to none in the CSEMS group. In a retrospective cohort trial, EUS-FNA was found to be highly accurate and safe in diagnosing patients with suspected pancreatic cancer, even in the presence of a plastic or metallic biliary stent. The presence of a stent did not contribute to a higher false-positive cytology rate.
Screening for cystic fibrosis in New York State: considerations for algorithm improvements.
Kay, Denise M; Maloney, Breanne; Hamel, Rhonda; Pearce, Melissa; DeMartino, Lenore; McMahon, Rebecca; McGrath, Emily; Krein, Lea; Vogel, Beth; Saavedra-Matiz, Carlos A; Caggana, Michele; Tavakoli, Norma P
2016-02-01
Newborn screening for cystic fibrosis (CF), a chronic progressive disease affecting mucus viscosity, has been beneficial in both improving life expectancy and the quality of life for individuals with CF. In New York State from 2007 to 2012 screening for CF involved measuring immunoreactive trypsinogen (IRT) levels in dried blood spots from newborns using the IMMUCHEM(™) Blood Spot Trypsin-MW ELISA kit. Any specimen in the top 5% IRT level underwent DNA analysis using the InPlex(®) CF Molecular Test. Of the 1.48 million newborns screened during the 6-year time period, 7631 babies were referred for follow-up. CF was confirmed in 251 cases, and 94 cases were diagnosed with CF transmembrane conductance regulated-related metabolic syndrome or possible CF. Nine reports of false negatives were made to the program. Variation in daily average IRT was observed depending on the season (4-6 ng/ml) and kit lot (<3 ng/ml), supporting the use of a floating cutoff. The screening method had a sensitivity of 96.5%, specificity of 99.6%, positive predictive value of 4.5%, and negative predictive value of 99.5%. Considerations for CF screening algorithms should include IRT variations resulting from age at specimen collection, sex, race/ethnicity, season, and manufacturer kit lots. Measuring IRT level in dried blood spots is the first-tier screen for CF. Current algorithms for CF screening lead to substantial false-positive referral rates. IRT values were affected by age of infant when specimen is collected, race/ethnicity and sex of infant, and changes in seasons and manufacturer kit lots The prevalence of CF in NYS is 1 in 4200 with the highest prevalence in White infants (1 in 2600) and the lowest in Black infants (1 in 15,400).
Can emergency physicians accurately and reliably assess acute vertigo in the emergency department?
Vanni, Simone; Nazerian, Peiman; Casati, Carlotta; Moroni, Federico; Risso, Michele; Ottaviani, Maddalena; Pecci, Rudi; Pepe, Giuseppe; Vannucchi, Paolo; Grifoni, Stefano
2015-04-01
To validate a clinical diagnostic tool, used by emergency physicians (EPs), to diagnose the central cause of patients presenting with vertigo, and to determine interrater reliability of this tool. A convenience sample of adult patients presenting to a single academic ED with isolated vertigo (i.e. vertigo without other neurological deficits) was prospectively evaluated with STANDING (SponTAneousNystagmus, Direction, head Impulse test, standiNG) by five trained EPs. The first step focused on the presence of spontaneous nystagmus, the second on the direction of nystagmus, the third on head impulse test and the fourth on gait. The local standard practice, senior audiologist evaluation corroborated by neuroimaging when deemed appropriate, was considered the reference standard. Sensitivity and specificity of STANDING were calculated. On the first 30 patients, inter-observer agreement among EPs was also assessed. Five EPs with limited experience in nystagmus assessment volunteered to participate in the present study enrolling 98 patients. Their average evaluation time was 9.9 ± 2.8 min (range 6-17). Central acute vertigo was suspected in 16 (16.3%) patients. There were 13 true positives, three false positives, 81 true negatives and one false negative, with a high sensitivity (92.9%, 95% CI 70-100%) and specificity (96.4%, 95% CI 93-38%) for central acute vertigo according to senior audiologist evaluation. The Cohen's kappas of the first, second, third and fourth steps of the STANDING were 0.86, 0.93, 0.73 and 0.78, respectively. The whole test showed a good inter-observer agreement (k = 0.76, 95% CI 0.45-1). In the hands of EPs, STANDING showed a good inter-observer agreement and accuracy validated against the local standard of care. © 2015 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.
Yamanaka, Takashi; Nemoto, Manabu; Bannai, Hiroshi; Tsujimura, Koji; Kondo, Takashi; Matsumura, Tomio; Gildea, Sarah; Cullinane, Ann
2016-03-01
Equine influenza (EI) is a highly contagious disease caused by viruses of the H3N8 subtype. The rapid diagnosis of EI is essential to reduce the disease spread. Many rapid antigen detection (RAD) tests for diagnosing human influenza are available, but their ability to diagnose EI has not been systematically evaluated. The aim of this study was to compare the performance of 22 RAD tests in the diagnosis of EI. The 22 RAD tests were performed on fivefold serial dilutions of EI virus to determine their detection limits. The four most sensitive RAD tests (ImmunoAce Flu, BD Flu examan, Quick chaser Flu A, B and ESPLINE Influenza A&B-N) were further evaluated using nasopharyngeal samples collected from experimentally infected and naturally infected horses. The results were compared to those obtained using molecular tests. The detection limits of the 22 RAD tests varied hugely. Even the four RAD tests showing the best sensitivity were 125-fold less sensitive than the molecular techniques. The duration of virus detection in the experimentally infected horses was shorter using the RAD tests than using the molecular techniques. The RAD tests detected between 27% and 73% of real-time RT-PCR-positive samples from naturally infected horses. The study demonstrated the importance of choosing the right RAD tests as only three of 22 were fit for diagnosing EI. It was also indicated that even RAD tests with the highest sensitivity serve only as an adjunct to molecular tests because of the potential for false-negative results. © 2015 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.
Implications of false positive serology of Toxoplasma gondii in a pre-transplant patient.
Beal, Stacy; Racsa, Lori; Alatoom, Adnan
2014-01-01
A 21-year-old white male with cystic fibrosis. Pre-transplant workup in preparation for bilateral lung transplant. Cystic fibrosis diagnosed at age 3, onset of insulin-dependent diabetes around age 20, and multiple hospitalizations for pulmonary and gastrointestinal complications. FAMILY AND SOCIAL HISTORY: The patient lives with his father and stepmother, has a pet bearded dragon, and has multiple tattoos and piercings. His stepmother has a cat, but he does not clean the litter box. The pre-transplant workup included several tests for infectious diseases, tests of organ function, radiology studies, and markers of malignancy. The only significant finding was a positive Toxoplasma gondii (T. gondii) IgM titer (> or = 1:40) (reference values for IgM: negative; < 1:40, positive; > or = 1:40) and IgG (1:2048) (reference values for IgG: negative; < 1:16, equivocal; > or = 1:16 - < 1:256, positive; > or = 1:256). Testing was done by indirect immunofluorescence assay (IFA) in April 2012 in our hospital laboratory. The patient was treated with sulfadiazine, leucovorin, and pyrimethamine. Three months later (July), he returned for follow-up testing. Real-time polymerase chain reaction (PCR) for T. gondii DNA performed by a reference laboratory was negative. One month later (August), Toxoplasma serology was performed by enzyme-linked immunosorbent assay (ELISA) by a different reference laboratory and showed an elevated IgM of 0.95 IU/mL (reference values: negative; < 0.55 IU/mL, equivocal; > or = 0.55- < 0.65 IU/mL, positive; > or = 0.65 IU/mL) and a normal level of IgG (< 4 IU/mL). At this time, PCR was repeated and was negative. An additional month later (September), the patient's serology studies were performed at a third reference laboratory and showed an elevated IgM of 1.32 IU/mL (reference values: negative; 0.89, equivocal; 0.90 - 1.09, positive; > 1.10) and a normal IgG.
2018-06-08
Estrogen Receptor Negative; HER2/Neu Negative; Invasive Breast Carcinoma; Progesterone Receptor Negative; Stage II Breast Cancer AJCC v6 and v7; Stage IIA Breast Cancer AJCC v6 and v7; Stage IIB Breast Cancer AJCC v6 and v7; Stage III Breast Cancer AJCC v7; Stage IIIA Breast Cancer AJCC v7; Stage IIIB Breast Cancer AJCC v7; Stage IIIC Breast Cancer AJCC v7; Triple-Negative Breast Carcinoma
Kim, Won Hwa; Kim, Hye Jung; Jung, Jin Hyang; Park, Ho Yong; Lee, Jeeyeon; Kim, Wan Wook; Park, Ji Young; Cheon, Hyejin; Lee, So Mi; Cho, Seung Hyun; Shin, Kyung Min; Kim, Gab Chul
2017-11-01
Ultrasonography-guided fine-needle aspiration (US-guided FNA) for axillary lymph nodes (ALNs) is currently used with various techniques for the initial staging of breast cancer and tagging of ALNs. With the implementation of the tattooing of biopsied ALNs, the rate of false-negative results of US-guided FNA for non-palpable and suspicious ALNs and concordance with sentinel lymph nodes were determined by node-to node analyses. A total of 61 patients with breast cancer had negative results for metastasis on US-guided FNA of their non-palpable and suspicious ALNs. The biopsied ALNs were tattooed with an injection of 1-3 mL Charcotrace (Phebra, Lane Cove West, Australia) ink and removed during sentinel lymph node biopsy or axillary dissection. We determined the rate of false-negative results and concordance with the sentinel lymph nodes by a retrospective review of surgical and pathologic findings. The association of false-negative results with clinical and imaging factors was evaluated using logistic regression. Of the 61 ALNs with negative results for US-guided FNA, 13 (21%) had metastases on final pathology. In 56 of 61 ALNs (92%), tattooed ALNs corresponded to the sentinel lymph nodes. Among the 5 patients (8%) without correspondence, 1 patient (2%) had 2 metastatic ALNs of 1 tattooed node and 1 sentinel lymph node. In multivariate analysis, atypical cells on FNA results (odds ratio = 20.7, p = 0.040) was independently associated with false-negative FNA results. False-negative ALNs after US-guided FNA occur at a rate of 21% and most of the tattooed ALNs showed concordance with sentinel lymph nodes. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
An empirical probability model of detecting species at low densities.
Delaney, David G; Leung, Brian
2010-06-01
False negatives, not detecting things that are actually present, are an important but understudied problem. False negatives are the result of our inability to perfectly detect species, especially those at low density such as endangered species or newly arriving introduced species. They reduce our ability to interpret presence-absence survey data and make sound management decisions (e.g., rapid response). To reduce the probability of false negatives, we need to compare the efficacy and sensitivity of different sampling approaches and quantify an unbiased estimate of the probability of detection. We conducted field experiments in the intertidal zone of New England and New York to test the sensitivity of two sampling approaches (quadrat vs. total area search, TAS), given different target characteristics (mobile vs. sessile). Using logistic regression we built detection curves for each sampling approach that related the sampling intensity and the density of targets to the probability of detection. The TAS approach reduced the probability of false negatives and detected targets faster than the quadrat approach. Mobility of targets increased the time to detection but did not affect detection success. Finally, we interpreted two years of presence-absence data on the distribution of the Asian shore crab (Hemigrapsus sanguineus) in New England and New York, using our probability model for false negatives. The type of experimental approach in this paper can help to reduce false negatives and increase our ability to detect species at low densities by refining sampling approaches, which can guide conservation strategies and management decisions in various areas of ecology such as conservation biology and invasion ecology.
Moschetta, Marco; Telegrafo, Michele; Capuano, Giulia; Rella, Leonarda; Scardapane, Arnaldo; Angelelli, Giuseppe; Stabile Ianora, Amato Antonio
2013-10-01
To assess the contribute of intra-prosthetic MRI virtual navigation for evaluating breast implants and detecting implant ruptures. Forty-five breast implants were evaluated by MR examination. Only patients with a clinical indication were assessed. A 1.5-T device equipped with a 4-channel breast coil was used by performing axial TSE-T2, axial silicone-only, axial silicone suppression and sagittal STIR images. The obtained dicom files were also analyzed by using virtual navigation software. Two blinded radiologists evaluated all MR and virtual images. Eight patients for a total of 13 implants underwent surgical replacement. Sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were calculated for both imaging strategies. Intra-capsular rupture was diagnosed in 13 out of 45 (29%) implants by using MRI. Basing on virtual navigation, 9 (20%) cases of intra-capsular rupture were diagnosed. Sensitivity, specificity, accuracy, PPV and NPV values of 100%, 86%, 89%, 62% and 100%, respectively, were found for MRI. Virtual navigation increased the previous values up to 100%, 97%, 98%, 89% and 100%. Intra-prosthetic breast MR virtual navigation can represent an additional promising tool for the evaluation of breast implants being able to reduce false positives and to provide a more accurate detection of intra-capsular implant rupture signs. Copyright © 2013 Elsevier Inc. All rights reserved.
FNA diagnostic value in patients with neck masses in two teaching hospitals in Iran.
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.
Li, Mengyao; Hong, Guini; Cheng, Jun; Li, Jing; Cai, Hao; Li, Xiangyu; Guan, Qingzhou; Tong, Mengsha; Li, Hongdong; Guo, Zheng
2016-01-01
To precisely diagnose metastasis state is important for tailoring treatments for gastric cancer patients. However, the routinely employed radiological and pathologic tests for tumour metastasis have considerable high false negative rates, which may retard the identification of reproducible metastasis-related molecular biomarkers for gastric cancer. In this research, using three datasets, we firstly shwed that differentially expressed genes (DEGs) between metastatic tissue samples and non-metastatic tissue samples could hardly be reproducibly detected with a proper statistical control when the metastatic and non-metastatic samples were defined by TNM stage alone. Then, assuming that undetectable micrometastases are the prime cause for recurrence of early stage patients with curative resection, we reclassified all the “non-metastatic” samples as metastatic samples whenever the patients experienced tumour recurrence during follow-up after tumour resection. In this way, we were able to find distinct and reproducible DEGs between the reclassified metastatic and non-metastatic tissue samples and concordantly significant DNA methylation alterations distinguishing metastatic tissues and non-metastatic tissues of gastric cancer. Our analyses suggested that the follow-up recurrence information for patients should be employed in the research of tumour metastasis in order to decrease the confounding effects of false non-metastatic samples with undetected micrometastases. PMID:27109211
Overview of Five-Years of Experience Performing Non-Invasive Fetal Sex Assessment in Maternal Blood
Perlado-Marina, Sara; Bustamante-Aragones, Ana; Horcajada, Laura; Trujillo-Tiebas, Maria Jose; Lorda-Sanchez, Isabel; Ruiz Ramos, Marta; Plaza, Javier; Rodriguez de Alba, Marta
2013-01-01
Since the discovery of the presence of fetal DNA in maternal blood, non-invasive fetal sex determination has been the test most widely translated into clinical practice. To date there is no agreement between the different laboratories performing such tests in relation to which is the best protocol. As a consequence there are almost as many protocols as laboratories offering the service, using different methodologies and thus obtaining different diagnostic accuracies. By the end of 2007, after a validation study performed in 316 maternal samples collected between the 5th and 12th week of gestation, the fetal sex determination was incorporated into clinical practice in our Service. The test is performed in the first trimester of pregnancy, and it is offered as part of the genetic counseling process for couples at risk of X-linked disorders. As a general rule and in order to avoid misdiagnosis, two samples at different gestational ages are tested per patient. The analysis is performed by the study of the SRY gene by RT-PCR. Two hundred and twenty six pregnancies have been tested so far in these 5 years. Neither false positives nor false negatives diagnoses have been registered, thus giving a diagnostic accuracy of 100%. PMID:26835681
ERIC Educational Resources Information Center
South, M.; Stephenson, K. G.; Nielson, C. A.; Maisel, M.; Top, D. N.; Kirwan, C. B.
2015-01-01
Bowler et al. ("Journal of Autism and Developmental Disorders" 44(9):2355-2362. doi:10.1007/s10803-014-2105-y, 2014) have suggested that a specific memory impairment in autism spectrum disorders (ASD) arises from hippocampal failure to consolidate multiple related pieces of information. Twenty-four adults diagnosed with ASD and matched…
Children of mothers diagnosed with serious mental illness: patterns and predictors of service use.
Mowbray, Carol T; Lewandowski, Lisa; Bybee, Deborah; Oyserman, Daphna
2004-09-01
Children who have a parent diagnosed with a mental illness are at risk of psychiatric and behavioral problems; yet, these children do not necessarily receive needed services. Research has investigated correlates of child mental health service use, but not for these high-risk children. This study is part of an NIMH-funded, longitudinal investigation and describes child problems, service use, and predictors of service use for 506 children of 252 mothers diagnosed with serious mental illness. Mothers are primarily poor, minority women from urban areas. A multilevel-model approach is used to examine service use for multiple siblings in a family. More than one third of children had received services (from school or mental health agencies) in their lifetimes. Service use was predicted by child demographic characteristics (being male, non-African American, and older), social context variables (more negative life events, less financial satisfaction, and more parenting dissatisfaction), and maternal psychiatric variables (positively by high levels of case management receipt and affective diagnoses, negatively by maternal substance abuse history). In a subsample of "target children," mothers' rating of child behavior problems additionally predicted service use. Implications of results for research and intervention are discussed.
Slater, Robert A; Koren, Shlomit; Ramot, Yoram; Buchs, Andreas; Rapoport, Micha J
2014-01-01
The Semmes-Weinstein monofilament is the most widely used test to diagnose the loss of protective sensation. The commonly used protocol of the International Consensus on the Diabetic Foot includes a 'sham' application that allows for false-positive answers. We sought to study the heretofore unexamined significance of false-positive answers. Forty-five patients with diabetes and a history of pedal ulceration (Group I) and 81 patients with diabetes but no history of ulceration (Group II) were studied. The three original sites of the International Consensus on the Diabetic Foot at the hallux, 1st metatarsal and 5th metatarsal areas were used. At each location, the test was performed three times: 2 actual and 1 "sham" applications. Scores were graded from 0 to 3 based upon correct responses. Determination of loss of protective sensation was performed with and without calculating a false-positive answer as a minus 1 score. False-positive responses were found in a significant percentage of patients with and without history of ulceration. Introducing false-positive results as minus 1 into the test outcome significantly increased the number of patients diagnosed with loss of protective sensation in both groups. False-positive answers can significantly affect Semmes-Weinstein monofilament test results and the diagnosis of LOPS. A model that accounts for false-positive answers is offered. Copyright © 2013 John Wiley & Sons, Ltd.
Walitt, Brian; Mackey, Rachel; Kuller, Lewis; Deane, Kevin D; Robinson, William; Holers, V Michael; Chang, Yue-Fang; Moreland, Larry
2013-05-01
Rheumatoid arthritis (RA) research using large databases is limited by insufficient case validity. Of 161,808 postmenopausal women in the Women's Health Initiative, 15,691 (10.2%) reported having RA, far higher than the expected 1% population prevalence. Since chart review for confirmation of an RA diagnosis is impractical in large cohort studies, the current study (2009-2011) tested the ability of baseline serum measurements of rheumatoid factor and anti-cyclic citrullinated peptide antibodies, second-generation assay (anti-CCP2), to identify physician-validated RA among the chart-review study participants with self-reported RA (n = 286). Anti-CCP2 positivity had the highest positive predictive value (PPV) (80.0%), and rheumatoid factor positivity the lowest (44.6%). Together, use of disease-modifying antirheumatic drugs and anti-CCP2 positivity increased PPV to 100% but excluded all seronegative cases (approximately 15% of all RA cases). Case definitions inclusive of seronegative cases had PPVs between 59.6% and 63.6%. False-negative results were minimized in these test definitions, as evidenced by negative predictive values of approximately 90%. Serological measurements, particularly measurement of anti-CCP2, improved the test characteristics of RA case definitions in the Women's Health Initiative.
Cost-effectiveness of the Xpert® MTB/RIF assay for tuberculosis diagnosis in Brazil.
Pinto, M; Steffen, R E; Cobelens, F; van den Hof, S; Entringer, A; Trajman, A
2016-05-01
The Xpert® MTB/RIF assay is being implemented as a substitute for sputum smear microscopy (SSM) in many low and high tuberculosis (TB) burden countries, including Brazil, a country with low multidrug resistance and moderate human immunodeficiency virus co-infection rates. Brazilian National TB Programme (NTP). We estimated the incremental cost-effectiveness ratio (ICER) of Xpert as a substitute for two SSM tests in the diagnosis of drug-susceptible TB. The costs for confirming each additional case and for avoiding treatment due to false-positive empirical diagnoses were estimated. The ICER was US$943 for each additional TB diagnosis and US$356 for each additional TB diagnosis with bacteriological confirmation, assuming 80% specificity of clinical diagnosis using both strategies. For every 100 000 patients with suspected TB, the NTP would spend an additional US$1.2 million per year to confirm 3344 more TB patients. The model was highly sensitive to specificity of clinical diagnosis after a negative test. Although the NTP has no threshold for cost-effectiveness, our model can provide support for decision makers in Brazil and other countries with a low prevalence of drug resistance among TB patients. Financial benefit can potentially be expected if physicians rely more on a negative Xpert result and empirical treatment is reduced.
Rosa-Jiménez, Francisco; Rosa-Jiménez, Ascensión; Lozano-Rodríguez, Aquiles; Santoro-Martínez, María Del Carmen; Duro-López, María Del Carmen; Carreras-Álvarez de Cienfuegos, Amelia
2015-01-01
To compare the efficacy of the most familiar clinical prediction rules in combination with D-dimer testing to rule out a diagnosis of deep vein thrombosis (DVT) in a hospital emergency department. Retrospective cross-sectional analysis of the case records of all patients attending a hospital emergency department with suspected lower-limb DVT between 1998 and 2002. Ten clinical prediction scores were calculated and D-dimer levels were available for all patients. The gold standard was ultrasound diagnosis of DVT by an independent radiologist who was blinded to clinical records. For each prediction rule, we analyzed the effectiveness of the prediction strategy defined by "low clinical probability and negative D-dimer level" against the ultrasound diagnosis. A total of 861 case records were reviewed and 577 cases were selected; the mean (SD) age was 66.7 (14.2) years. DVT was diagnosed in 145 patients (25.1%). Only the Wells clinical prediction rule and 4 other models had a false negative rate under 2%. The Wells criteria and the score published by Johanning and colleagues identified higher percentages of cases (15.6% and 11.6%, respectively). This study shows that several clinical prediction rules can be safely used in the emergency department, although none of them have proven more effective than the Wells criteria.
Viaux-Savelon, Sylvie; Dommergues, Marc; Rosenblum, Ouriel; Bodeau, Nicolas; Aidane, Elizabeth; Philippon, Odile; Mazet, Philippe; Vibert-Guigue, Claude; Vauthier-Brouzes, Danièle; Feldman, Ruth; Cohen, David
2012-01-01
Background In up to 5% of pregnancies, ultrasound screening detects a “soft marker” (SM) that places the foetus at risk for a severe abnormality. In most cases, prenatal diagnostic work-up rules out a severe defect. We aimed to study the effects of false positive SM on maternal emotional status, maternal representations of the infant, and mother-infant interaction. Methodology and Principal Findings Utilizing an extreme-case prospective case control design, we selected from a group of 244 women undergoing ultrasound, 19 pregnant women whose foetus had a positive SM screening and a reassuring diagnostic work up, and 19 controls without SM matched for age and education. In the third trimester of pregnancy, within one week after delivery, and 2 months postpartum, we assessed anxiety, depression, and maternal representations. Mother-infant interactions were videotaped during feeding within one week after delivery and again at 2 months postpartum and coded blindly using the Coding Interactive Behavior (CIB) scales. Anxiety and depression scores were significantly higher at all assessment points in the SM group. Maternal representations were also different between SM and control groups at all study time. Perturbations to early mother-infant interactions were observed in the SM group. These dyads showed greater dysregulation, lower maternal sensitivity, higher maternal intrusive behaviour and higher infant avoidance. Multivariate analysis showed that maternal representation and depression at third trimester predicted mother-infant interaction. Conclusion False positive ultrasound screenings for SM are not benign and negatively affect the developing maternal-infant attachment. Medical efforts should be directed to minimize as much as possible such false diagnoses, and to limit their psychological adverse consequences. PMID:22292077
Pan, Liping; Jia, Hongyan; Liu, Fei; Sun, Huishan; Gao, Mengqiu; Du, Fengjiao; Xing, Aiying; Du, Boping; Sun, Qi; Wei, Rongrong; Gu, Shuxiang; Zhang, Zongde
2015-04-01
To investigate the risk factors for false-negative T-SPOT.TB results in patients with pulmonary TB (PTB) and extra-pulmonary TB (EPTB). Patients with suspected TB who underwent valid T-SPOT.TB tests were prospectively enrolled at Beijing Chest Hospital between November 2012 and November 2013. Basic characters and clinical laboratory findings were compared between true-positive and false-negative T-SPOT.TB groups. Of 1928 suspected TB patients, 774 (530 PTB and 244 EPTB) microbiologically/histopathogenically-confirmed patients (636 culture-confirmed) were analyzed. Forty-six PTB patients (8.7%) and 32 EPTB patients (13.1%) had negative T-SPOT.TB results. Multivariate analysis showed that increased age [odds radio (OR) 2.26, 95% confidence interval (CI) 1.11-4.58], over-weight (BMI ≥ 25 kg/m(2), OR 2.43, 95% CI 1.05-5.63), and a longer period of illness before hospitalization (>6 months, OR 2.46, 95% CI 1.24-4.92) were independent risk factors for false-negative T-SPOT.TB results in PTB patients. In EPTB patients, increased age (OR 2.42, 95% CI 1.09-5.35) also showed an independent association with false-negative T-SPOT.TB results. Careful interpretation of negative T-SPOT.TB results is necessary in older patients with suspected PTB or EPTB, and in PTB patients who are over-weight or have had longer periods of illness before hospitalization. Copyright © 2015 The British Infection Association. Published by Elsevier Ltd. All rights reserved.
Acetaminophen Adducts Detected in Serum of Pediatric Patients With Acute Liver Failure.
Alonso, Estella M; James, Laura P; Zhang, Song; Squires, Robert H
2015-07-01
Previous studies in patients with acute liver failure identified acetaminophen (APAP) protein adducts in the serum of 12% and 19% of children and adults, respectively, with acute liver failure of indeterminate etiology. This article details the testing of APAP adducts in a subset (n = 393) of patients with varied diagnoses in the Pediatric Acute Liver Failure Study Group (PALFSG). Serum samples were available from 393 participants included in the PALFSG registry. Adduct measurement was performed using validated methods. Participants were grouped by diagnostic category as known APAP overdose, known other diagnosis, and indeterminate etiology. Demographic and clinical characteristics and participant outcomes were compared by adduct status (positive or negative) within each group. APAP adduct testing was positive in 86% of participants with known APAP overdose, 6% with other known diagnoses, and 11% with an indeterminate cause of liver failure. Adduct-positive participants were noted to have marked elevation of serum alanine aminotransferase and aspartate aminotransferase coupled with total serum bilirubin that was significantly lower than adduct-negative patients. In the indeterminate group, adduct-positive patients had different outcomes than adduct-negative patients (P = 0.03); spontaneous survival was 16 of 21 (76%) in adduct-positive patients versus 75 of 169 (44%) in adduct-negative patients. Prognosis did not vary by adduct status in patients with known diagnoses. Furthermore, study is needed to understand the relation of APAP exposure, as determined by the presence of APAP adducts, to the clinical phenotype and outcomes of children with acute liver failure.
Nelissen, Sara; Beullens, Kathleen; Lemal, Marijke; Van den Bulck, Jan
2015-03-01
Few studies have explored the impact of mass media on fear of cancer levels. This study investigates whether television and Internet use are associated with fear of cancer, and whether this association is different for cancer diagnosed and nondiagnosed individuals. A quantitative, standardized survey was used and administered to 2008 respondents in Flanders (Belgium), of which 621 individuals were diagnosed with cancer. For statistical analyses, hierarchical regression analyses, independent samples T-tests and post hoc mediation analyses were conducted. The results indicated that cancer diagnosed individuals differed from nondiagnosed individuals in terms of perceived cancer susceptibility, perceived cancer severity, fear of cancer, and media use. Furthermore, television exposure was directly and positively related to fear of cancer, whereas Internet use was not. The relationship between television and Internet use and fear of cancer was not different for cancer diagnosed and nondiagnosed individuals. Additional post hoc mediation analyses, however, seemed to suggest that watching more television and surfing more on the Internet could both lead to having a more negative perceived health and this was in turn associated with higher fear of cancer. To help reduce the burden of fear of cancer, cancer educators and individuals working with cancer patients need to be aware of the possible negative effects media use might have on health perception and on the levels of fear of cancer.
The value of a transformation zone component in anal cytology to detect HSIL.
Roberts, Jennifer M; Jin, Fengyi; Thurloe, Julia K; Ekman, Deborah; Adams, Marjorie K; McDonald, Ross L; Biro, Clare; Poynten, I Mary; Grulich, Andrew E; Farnsworth, Annabelle
2016-08-01
In a cytology-based screening program intended to prevent anal cancer, the anal transformation zone (TZ) should be adequately sampled because it is the site most susceptible to the development of the cancer precursor, high-grade squamous intraepithelial lesion (HSIL). An adequate TZ component is defined as comprising at least 10 rectal columnar or squamous metaplastic cells. In the current study, the authors examined whether the presence of a TZ component in anal cytology correlated with the detection of histological HSIL. In a natural history study of anal human papillomavirus infection in homosexual men, all participants underwent liquid-based cytology and high-resolution anoscopy (HRA) with or without biopsy at each visit. True-negative cytology (negative cytology with non-HSIL biopsy or negative HRA), false-negative cytology (negative cytology with HSIL biopsy), and true-positive cytology (abnormal cytology with HSIL biopsy) were compared with regard to the presence or absence of a TZ component. Of 617 participants, baseline results included 155 true-positive results, 191 true-negative results, and 31 false-negative results. The absence of an adequate TZ component was found to be significantly higher for false-negative (32.3%) than for either true-positive (11.0%; P = .0034) or true-negative (13.1%; P = .0089) results. Significantly more false-negative cases lacked a TZ component compared with either true-positive or true-negative cases. TZ cells may be an important indicator of sample quality for anal cytology because, unlike cervical sampling, the anal canal is not visualized during cytology sampling. Cancer Cytopathol 2016;124:596-601. © 2016 American Cancer Society. © 2016 American Cancer Society.
Yu, Nancy Xiaonan; Chen, Lihua; Ye, Zhi; Li, Xiaoming; Lin, Danhua
2017-01-01
The experience of HIV, as a life-transforming event, might produce both negative and positive outcomes. Guided by the stress appraisal model, the present study investigated the hypothesized pathways in predicting symptomatology and posttraumatic growth (PTG) in a sample of Chinese male patients with HIV (PHIV) who were mainly newly diagnosed, young, and homosexual. In this cross-sectional study, 141 Chinese male PHIV (87.2% of them were homosexual) completed measures of making negative/positive sense of adversity, resilience, depression, posttraumatic stress disorder (PTSD), and PTG. The path analysis results showed that making negative sense of adversity was associated with depression and PTSD, partially mediated by low levels of resilience, whereas making positive sense of adversity was associated with PTG, partially mediated by resilience. The results suggest that negative and positive outcomes of trauma are impacted by making negative and positive sense of adversity, respectively, via two separate pathways, both mediated by resilience. Our findings contribute to an understanding of the cognitive process of symptomatology and PTG in the HIV context. Theoretical considerations, clinical implications, and future directions are discussed.
True detection limits in an experimental linearly heteroscedastic system. Part 1
NASA Astrophysics Data System (ADS)
Voigtman, Edward; Abraham, Kevin T.
2011-11-01
Using a lab-constructed laser-excited filter fluorimeter deliberately designed to exhibit linearly heteroscedastic, additive Gaussian noise, it has been shown that accurate estimates may be made of the true theoretical Currie decision levels ( YC and XC) and true Currie detection limits ( YD and XD) for the detection of rhodamine 6 G tetrafluoroborate in ethanol. The obtained experimental values, for 5% probability of false positives and 5% probability of false negatives, were YC = 56.1 mV, YD = 125. mV, XC = 0.132 μg /mL and XD = 0.294 μg /mL. For 5% probability of false positives and 1% probability of false negatives, the obtained detection limits were YD = 158. mV and XD = 0.372 μg /mL. These decision levels and corresponding detection limits were shown to pass the ultimate test: they resulted in observed probabilities of false positives and false negatives that were statistically equivalent to the a priori specified values.
Kufa, Tendesayi; Kharsany, Ayesha BM; Cawood, Cherie; Khanyile, David; Lewis, Lara; Grobler, Anneke; Chipeta, Zawadi; Bere, Alfred; Glenshaw, Mary; Puren, Adrian
2017-01-01
Abstract Introduction: We describe the overall accuracy and performance of a serial rapid HIV testing algorithm used in community-based HIV testing in the context of a population-based household survey conducted in two sub-districts of uMgungundlovu district, KwaZulu-Natal, South Africa, against reference fourth-generation HIV-1/2 antibody and p24 antigen combination immunoassays. We discuss implications of the findings on rapid HIV testing programmes. Methods: Cross-sectional design: Following enrolment into the survey, questionnaires were administered to eligible and consenting participants in order to obtain demographic and HIV-related data. Peripheral blood samples were collected for HIV-related testing. Participants were offered community-based HIV testing in the home by trained field workers using a serial algorithm with two rapid diagnostic tests (RDTs) in series. In the laboratory, reference HIV testing was conducted using two fourth-generation immunoassays with all positives in the confirmatory test considered true positives. Accuracy, sensitivity, specificity, positive predictive value, negative predictive value and false-positive and false-negative rates were determined. Results: Of 10,236 individuals enrolled in the survey, 3740 were tested in the home (median age 24 years (interquartile range 19–31 years), 42.1% males and HIV positivity on RDT algorithm 8.0%). From those tested, 3729 (99.7%) had a definitive RDT result as well as a laboratory immunoassay result. The overall accuracy of the RDT when compared to the fourth-generation immunoassays was 98.8% (95% confidence interval (CI) 98.5–99.2). The sensitivity, specificity, positive predictive value and negative predictive value were 91.1% (95% CI 87.5–93.7), 99.9% (95% CI 99.8–100), 99.3% (95% CI 97.4–99.8) and 99.1% (95% CI 98.8–99.4) respectively. The false-positive and false-negative rates were 0.06% (95% CI 0.01–0.24) and 8.9% (95% CI 6.3–12.53). Compared to true positives, false negatives were more likely to be recently infected on limited antigen avidity assay and to report antiretroviral therapy (ART) use. Conclusions: The overall accuracy of the RDT algorithm was high. However, there were few false positives, and the sensitivity was lower than expected with high false negatives, despite implementation of quality assurance measures. False negatives were associated with recent (early) infection and ART exposure. The RDT algorithm was able to correctly identify the majority of HIV infections in community-based HIV testing. Messaging on the potential for false positives and false negatives should be included in these programmes. PMID:28872274
Rotondi, Mario; Chiovato, Luca; Pacini, Furio; Bartalena, Luigi; Vitti, Paolo
2018-05-01
The 2017 American Thyroid Association guidelines for the diagnosis and management of thyroid disease during pregnancy and the postpartum were published six years after the previous ones. They provide comprehensive clinical recommendations for the whole spectrum of thyroid diseases, as well as for optimal iodine intake during pregnancy, postpartum, and lactation. The present position statement mainly regards the recommended flow chart for therapeutic decision making in pregnant women being diagnosed with subclinical hypothyroidism. Here, we comment on the major biochemical and clinical situations and the corresponding therapeutic recommendations. In particular, we welcome the critical revision of the thyrotropin (TSH) reference range in pregnancy, and we agree that there is no need to treat thyroid peroxidase antibody-negative women with a serum TSH ranging from 2.5 μIU/mL to the upper limit of the reference range. This recommendation will hopefully reduce the huge proportion of healthy pregnant women in whom, according to the previous guidelines, levothyroxine therapy had to be initiated. On the other hand, we are concerned with the recommendation to only "consider treatment" in thyroid peroxidase antibody-negative pregnant women with a serum TSH ranging from the upper limit of the reference range to 10.0 μIU/mL. This is because thyroid antibodies may be falsely negative during gestation, and serum negative chronic autoimmune thyroiditis is a well-known clinical entity even outside pregnancy. Based on these and other arguments, we recommend treatment with levothyroxine in pregnant women with TSH levels ranging between the upper limit of the reference range and 10.0 μIU/mL independently from their thyroid antibody status.
False-Positive Rate of AKI Using Consensus Creatinine-Based Criteria.
Lin, Jennie; Fernandez, Hilda; Shashaty, Michael G S; Negoianu, Dan; Testani, Jeffrey M; Berns, Jeffrey S; Parikh, Chirag R; Wilson, F Perry
2015-10-07
Use of small changes in serum creatinine to diagnose AKI allows for earlier detection but may increase diagnostic false-positive rates because of inherent laboratory and biologic variabilities of creatinine. We examined serum creatinine measurement characteristics in a prospective observational clinical reference cohort of 2267 adult patients with AKI by Kidney Disease Improving Global Outcomes creatinine criteria and used these data to create a simulation cohort to model AKI false-positive rates. We simulated up to seven successive blood draws on an equal population of hypothetical patients with unchanging true serum creatinine values. Error terms generated from laboratory and biologic variabilities were added to each simulated patient's true serum creatinine value to obtain the simulated measured serum creatinine for each blood draw. We determined the proportion of patients who would be erroneously diagnosed with AKI by Kidney Disease Improving Global Outcomes creatinine criteria. Within the clinical cohort, 75.0% of patients received four serum creatinine draws within at least one 48-hour period during hospitalization. After four simulated creatinine measurements that accounted for laboratory variability calculated from assay characteristics and 4.4% of biologic variability determined from the clinical cohort and publicly available data, the overall false-positive rate for AKI diagnosis was 8.0% (interquartile range =7.9%-8.1%), whereas patients with true serum creatinine ≥1.5 mg/dl (representing 21% of the clinical cohort) had a false-positive AKI diagnosis rate of 30.5% (interquartile range =30.1%-30.9%) versus 2.0% (interquartile range =1.9%-2.1%) in patients with true serum creatinine values <1.5 mg/dl (P<0.001). Use of small serum creatinine changes to diagnose AKI is limited by high false-positive rates caused by inherent variability of serum creatinine at higher baseline values, potentially misclassifying patients with CKD in AKI studies. Copyright © 2015 by the American Society of Nephrology.
Surveillance of women with a personal history of breast cancer by tumour subtype.
Benveniste, A P; Dryden, M J; Bedrosian, I; Morrow, P K; Bassett, R L; Yang, W
2017-03-01
To determine if the rate and timing of a second breast cancer event (SBCE) in women with a personal history of breast cancer varies by disease subtype or breast imaging method. A retrospective review was performed of women with a SBCE from January 2006 to December 2010 at a single institution. Data analysed included oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) status of the primary and second breast cancers; mammographic and ultrasound (US) features from SBCE; and the time interval between both events. Of 207 patients diagnosed with a SBCE, the median age at first diagnosis was 50.6 years, range 24.8 to 80.2; at second diagnosis was 56.2 years, range 25.8 to 87.9. Eleven percent of SBCE were diagnosed >10 years after the primary cancer diagnosis. The median time between the first and second diagnosis for ER-positive patients was 2.7 years (range 0.7-17.4 years); and 1.9 years for ER-negative patients, (range 0.4-23.4 years; p<0.002). Patients with triple-negative breast cancer (TNBC) had a shorter time between diagnoses than others (p=0.0003). At 3, 5, and 10 years, 85%, 92%, and 97% of ER-negative and 54%, 81%, and 95% of ER-positive tumours, respectively, had recurred. ER-negative tumours and TNBC were more likely to be visible at US. There may be a role for customised imaging surveillance of women with a personal history of breast cancer (PHBC) after 10 years. Further studies are necessary to determine if US may be valuable in the surveillance of patients with ER-negative and TNBC tumours. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Chen, Qianting; Dai, Congling; Zhang, Qianjun; Du, Juan; Li, Wen
2016-10-01
To study the prediction performance evaluation with five kinds of bioinformatics software (SIFT, PolyPhen2, MutationTaster, Provean, MutationAssessor). From own database for genetic mutations collected over the past five years, Chinese literature database, Human Gene Mutation Database, and dbSNP, 121 missense mutations confirmed by functional studies, and 121 missense mutations suspected to be pathogenic by pedigree analysis were used as positive gold standard, while 242 missense mutations with minor allele frequency (MAF)>5% in dominant hereditary diseases were used as negative gold standard. The selected mutations were predicted with the five software. Based on the results, the performance of the five software was evaluated for their sensitivity, specificity, positive predict value, false positive rate, negative predict value, false negative rate, false discovery rate, accuracy, and receiver operating characteristic curve (ROC). In terms of sensitivity, negative predictive value and false negative rate, the rank was MutationTaster, PolyPhen2, Provean, SIFT, and MutationAssessor. For specificity and false positive rate, the rank was MutationTaster, Provean, MutationAssessor, SIFT, and PolyPhen2. For positive predict value and false discovery rate, the rank was MutationTaster, Provean, MutationAssessor, PolyPhen2, and SIFT. For area under the ROC curve (AUC) and accuracy, the rank was MutationTaster, Provean, PolyPhen2, MutationAssessor, and SIFT. The prediction performance of software may be different when using different parameters. Among the five software, MutationTaster has the best prediction performance.
False Positive and False Negative Effects on Network Attacks
NASA Astrophysics Data System (ADS)
Shang, Yilun
2018-01-01
Robustness against attacks serves as evidence for complex network structures and failure mechanisms that lie behind them. Most often, due to detection capability limitation or good disguises, attacks on networks are subject to false positives and false negatives, meaning that functional nodes may be falsely regarded as compromised by the attacker and vice versa. In this work, we initiate a study of false positive/negative effects on network robustness against three fundamental types of attack strategies, namely, random attacks (RA), localized attacks (LA), and targeted attack (TA). By developing a general mathematical framework based upon the percolation model, we investigate analytically and by numerical simulations of attack robustness with false positive/negative rate (FPR/FNR) on three benchmark models including Erdős-Rényi (ER) networks, random regular (RR) networks, and scale-free (SF) networks. We show that ER networks are equivalently robust against RA and LA only when FPR equals zero or the initial network is intact. We find several interesting crossovers in RR and SF networks when FPR is taken into consideration. By defining the cost of attack, we observe diminishing marginal attack efficiency for RA, LA, and TA. Our finding highlights the potential risk of underestimating or ignoring FPR in understanding attack robustness. The results may provide insights into ways of enhancing robustness of network architecture and improve the level of protection of critical infrastructures.
What Is a False Negative Sentinel Node Biopsy: Definition, Reasons and Ways to Minimize It?
Kataria, Kamal; Srivastava, Anurag; Qaiser, Darakhshan
2016-10-01
Sentinel node biopsy helps in assessing the involvement of axillary lymph node without the morbidity of full axillary lymph node dissection, namely arm and shoulder pain, paraesthesia and lymphoedema. The various methods described in the literature identify the sentinel lymph nodes in approximately 96 % of cases and associated with a false negativity rate of 5 to 10 %. A false negative sentinel node is defined as the proportion of cases in whom sentinel node biopsy is reported as negative, but the rest of axillary lymph node(s) harbours cancer cells. The possible causes of a false negative sentinel lymph node may be because of blocked lymphatics either by cancer cells or following fibrosis of previous surgery/radiotherapy, and an alternative pathway opens draining the blue dye or isotope to another uninvolved node . The other reasons may be two lymphatic pathways for a tumour area, the one opening to a superficial node and the other in deep nodes. Sometimes, lymphatics do not relay into a node but traverse it going to a higher node. In some patients, the microscopic focus of metastasis inside a lymph node is so small-micrometastasis (i.e. between 0.2 and 2 mm) or isolated tumour cells (i.e. less than 0.2 mm) that is missed by the pathologist. The purpose of this review is to clear some fears lurking in the mind of most surgeons about the false negative sentinel lymph node (FNSLN).
Desai, Vishal; Cox, Mougnyan; Deshmukh, Sandeep; Roth, Christopher G
2018-04-20
In the emergency setting, flank pain commonly leads to a noncontrast CT despite a significant percentage of patients having alternative diagnoses, often difficult to characterize without contrast. We investigated the combined utility of urinalysis and history of urolithiasis in identifying patients who are unlikely to have urolithiasis and may benefit from a contrast-enhanced study. Retrospective review of 350 patients from May 2013 to May 2016 was performed for patients in the emergency department with renal colic that underwent noncontrast CT and urinalysis testing. Urolithiasis was present in 282 of the 350 patients reviewed (81%), of which 175 (62%) had an obstructing calculus. RBC-positive urinalysis was present in 231 patients with calculi on CT (sensitivity 82%). Patient history of urolithiasis plus urinalysis had a sensitivity of 94% for detecting calculi. Thirty-five patients (10%) had alternative diagnoses, 33 of which were in patients without obstructing calculi. Sixty-seven patients underwent noncontrast CT despite no history of urolithiasis and a negative urinalysis, 10 of which (15%) had alternative diagnoses. Only three cases in this subset (4%) had nonobstructing 1-2-mm calculi, potentially missed with contrast. In this subset, the projected proportion of optimally characterized cases with intravenous contrast is 96%, compared to 85% without contrast (p = .03). Given the high combined sensitivity of urinalysis and patient history (94%), this simple analysis can confidently direct clinicians to a contrast-enhanced CT in "rule-out" cases of flank pain in patients with a negative history and negative urinalysis, particularly given that 15% of these patients had alternative diagnoses.
Herbert, Cornelia; Kübler, Andrea
2011-01-01
The present study investigated event-related brain potentials elicited by true and false negated statements to evaluate if discrimination of the truth value of negated information relies on conscious processing and requires higher-order cognitive processing in healthy subjects across different levels of stimulus complexity. The stimulus material consisted of true and false negated sentences (sentence level) and prime-target expressions (word level). Stimuli were presented acoustically and no overt behavioral response of the participants was required. Event-related brain potentials to target words preceded by true and false negated expressions were analyzed both within group and at the single subject level. Across the different processing conditions (word pairs and sentences), target words elicited a frontal negativity and a late positivity in the time window from 600-1000 msec post target word onset. Amplitudes of both brain potentials varied as a function of the truth value of the negated expressions. Results were confirmed at the single-subject level. In sum, our results support recent suggestions according to which evaluation of the truth value of a negated expression is a time- and cognitively demanding process that cannot be solved automatically, and thus requires conscious processing. Our paradigm provides insight into higher-order processing related to language comprehension and reasoning in healthy subjects. Future studies are needed to evaluate if our paradigm also proves sensitive for the detection of consciousness in non-responsive patients.
Wiwanitkit, Viroj; Udomsantisuk, Nibhond; Boonchalermvichian, Chaiyaporn
2005-06-01
The aim of this study was to evaluate the diagnostic properties of urine Gram stain and urine microscopic examination for screening for urinary tract infection (UTI), and to perform an additional cost utility analysis. This descriptive study was performed on 95 urine samples sent for urine culture to the Department of Microbiology, Faculty of Medicine, Chulalongkorn University. The first part of the study was to determine the diagnostic properties of two screening tests (urine Gram stain and urine microscopic examination). Urine culture was set as the gold standard and the results from both methods were compared to this. The second part of this study was to perform a cost utility analysis. The sensitivity of urine Gram stain was 96.2%, the specificity 93.0%, the positive predictive value 94.3% and the negative predictive value 95.2%. False positives occurred with a frequency of 7.0% and false negatives 3.8%. For the microscopic examination, the sensitivity was 65.4%, specificity 74.4%, positive predictive value 75.6% and negative predictive value 64.0%. False positives occurred with a frequency of 25.6% and false negatives 34.6%. Combining urine Gram stain and urine microscopic examination, the sensitivity was 98.1%, specificity 74.4%, positive predictive value 82.3% and negative predictive value 97.0%. False positives occurred with a frequency of 25.6% and false negatives 1.9%. However, the cost per utility of the combined method was higher than either urine microscopic examination or urine Gram stain alone. Urine Gram stain provided the lowest cost per utility. Economically, urine Gram stain is the proper screening tool for presumptive diagnosis of UTI.
2018-04-13
Estrogen Receptor Positive; HER2/Neu Negative; Male Breast Carcinoma; Stage IA Breast Cancer; Stage IB Breast Cancer; Stage IIA Breast Cancer; Stage IIB Breast Cancer; Stage IIIA Breast Cancer; Stage IIIB Breast Cancer; Stage IIIC Breast Cancer
Evaluation of Extinction as a Functional Treatment for Binge Eating
ERIC Educational Resources Information Center
Bosch, Amanda; Miltenberger, Raymond G.; Gross, Amy; Knudson, Peter; Breitwieser, Carrie Brower
2008-01-01
Binge eating is a serious behavior problem exhibited by individuals diagnosed with binge eating disorder and bulimia nervosa. Binge eating is thought to be maintained by automatic negative reinforcement in the form of relief from negative emotional responding. Current treatments produce only moderate abstinence, perhaps because they do not attempt…
Bosch, Xavier; Coloma, Emmanuel; Donate, Carolina; Colomo, Lluís; Doti, Pamela; Jordán, Anna; López-Soto, Alfonso
2014-01-01
Abstract Although rapid diagnostic testing is essential in suspicious peripheral lymphadenopathy, delays in accessing them can be considerable. We investigated the usefulness of an internist-led outpatient quick diagnosis unit (QDU) in assessing patients with unexplained peripheral lymphadenopathy, focusing on the characteristics, diagnostic, and treatment waiting times of those with malignancy. Patients aged ≥18 years, consecutively referred from 12 primary health care centers (PHCs) or the emergency department (ED) for unexplained peripheral lymphadenopathy, were prospectively evaluated during 7 years. Diagnostic investigations were done using a predefined study protocol. Three experienced cytopathologists performed a fine-needle aspiration cytology (FNAC) systematic approach of clinically suspicious lymphadenopathy with cytomorphology and immunophenotyping analyses. We evaluated 372 patients with a mean age (SD) of 45.3 (13.8) years; 56% were women. Malignancy was diagnosed in 120 (32%) patients, including 81 lymphomas and 39 metastatic tumors. Metastatic lymphadenopathy was diagnosed by FNAC in all 39 patients and the primary tumor site was identified in 82% of them when cytomorphology and immunocytochemistry were combined. A correct diagnosis of lymphoma was reached by FNAC in 73% of patients. When accepting “suspicious of” as correct diagnosis, the FNAC diagnosis rate of lymphoma increased to 94%. Among patients with malignancy, FNAC yielded 1.3% of false negatives and no false positives. All patients with an FNAC report of correct or suspicious lymphoma underwent a surgical biopsy, as it is a mandatory requirement of the hematology department. Mean times from first QDU visit to FNAC diagnosis of malignancy were 5.4 days in metastatic lymphadenopathy and 7.5 days in lymphoma. Mean times from receiving the initial referral report to first treatment were 29.2 days in metastatic lymphadenopathy and 40 days in lymphoma. In conclusion, a distinct internal medicine QDU allows an expeditious, agile, and prearranged system to diagnose malignant peripheral lymphadenopathy. Because of the close collaboration with the cytopathology unit and the FNAC methodical approach, diagnostic and treatment waiting times of patients with malignancy fulfilled national and international time frame standards. This particular diagnostic delivery unit could help overcome the difficulties facing PHC, ED, and other physicians when trying to provide rapid access to investigations to patients with troublesome lymphadenopathy. PMID:25310744
Bosch, Xavier; Coloma, Emmanuel; Donate, Carolina; Colomo, Lluís; Doti, Pamela; Jordán, Anna; López-Soto, Alfonso
2014-10-01
Although rapid diagnostic testing is essential in suspicious peripheral lymphadenopathy, delays in accessing them can be considerable. We investigated the usefulness of an internist-led outpatient quick diagnosis unit (QDU) in assessing patients with unexplained peripheral lymphadenopathy, focusing on the characteristics, diagnostic, and treatment waiting times of those with malignancy. Patients aged ≥ 18 years, consecutively referred from 12 primary health care centers (PHCs) or the emergency department (ED) for unexplained peripheral lymphadenopathy, were prospectively evaluated during 7 years. Diagnostic investigations were done using a predefined study protocol. Three experienced cytopathologists performed a fine-needle aspiration cytology (FNAC) systematic approach of clinically suspicious lymphadenopathy with cytomorphology and immunophenotyping analyses. We evaluated 372 patients with a mean age (SD) of 45.3 (13.8) years; 56% were women. Malignancy was diagnosed in 120 (32%) patients, including 81 lymphomas and 39 metastatic tumors. Metastatic lymphadenopathy was diagnosed by FNAC in all 39 patients and the primary tumor site was identified in 82% of them when cytomorphology and immunocytochemistry were combined. A correct diagnosis of lymphoma was reached by FNAC in 73% of patients. When accepting "suspicious of" as correct diagnosis, the FNAC diagnosis rate of lymphoma increased to 94%. Among patients with malignancy, FNAC yielded 1.3% of false negatives and no false positives. All patients with an FNAC report of correct or suspicious lymphoma underwent a surgical biopsy, as it is a mandatory requirement of the hematology department. Mean times from first QDU visit to FNAC diagnosis of malignancy were 5.4 days in metastatic lymphadenopathy and 7.5 days in lymphoma. Mean times from receiving the initial referral report to first treatment were 29.2 days in metastatic lymphadenopathy and 40 days in lymphoma. In conclusion, a distinct internal medicine QDU allows an expeditious, agile, and prearranged system to diagnose malignant peripheral lymphadenopathy. Because of the close collaboration with the cytopathology unit and the FNAC methodical approach, diagnostic and treatment waiting times of patients with malignancy fulfilled national and international time frame standards. This particular diagnostic delivery unit could help overcome the difficulties facing PHC, ED, and other physicians when trying to provide rapid access to investigations to patients with troublesome lymphadenopathy.
Girometti, Nicolò; Gutierrez, Angela; Nwokolo, Nneka; McOwan, Alan; Whitlock, Gary
2017-08-01
HIV pre-exposure prophylaxis (PrEP) is becoming a pivotal strategy for HIV prevention. Understanding the impact of risk factors for HIV transmission to identify those at highest risk would favour the implementation of PrEP, currently limited by costs. In this service evaluation, we estimated the incidence of bacterial STIs in men who have sex with men (MSM) diagnosed with early syphilis attending a London sexual health clinic according to their HIV status. In addition, we estimated the incidence of HIV infection in HIV-negative MSM, following a diagnosis of early syphilis. We undertook a retrospective case note review of all MSM patients diagnosed with early syphilis between January and June 2014. A number of sexual health screens and diagnoses of chlamydia, gonorrhoea and HIV were prospectively analysed following the syphilis diagnosis. 206 MSM were diagnosed with early syphilis. 110 (53%) were HIV-negative at baseline, 96 (47%) were HIV-positive. Only age (37 vs 32 years, p=0.0005) was significantly different according to HIV status of MSM at baseline. In HIV-negative versus HIV-positive MSM, incidence of rectal chlamydia infection at follow-up was 27 cases vs 50/100 person-years of follow-up (PYFU) (p=0.0039), 33 vs 66/100 PYFU (p=0.0044) for rectal gonorrhoea and 10 vs 26/100 PYFU (p=0.0044) for syphilis reinfection, respectively. Total follow-up for 110 HIV-negative MSM was 144 person-years. HIV incidence was 8.3/100 PYFU (CI 4.2 to 14). A diagnosis of early syphilis carries a high risk of consequent HIV seroconversion and should warrant prioritised access to prevention measures such as PrEP and regular STI screening to prevent HIV transmission. 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/.
ClubSub-P: Cluster-Based Subcellular Localization Prediction for Gram-Negative Bacteria and Archaea
Paramasivam, Nagarajan; Linke, Dirk
2011-01-01
The subcellular localization (SCL) of proteins provides important clues to their function in a cell. In our efforts to predict useful vaccine targets against Gram-negative bacteria, we noticed that misannotated start codons frequently lead to wrongly assigned SCLs. This and other problems in SCL prediction, such as the relatively high false-positive and false-negative rates of some tools, can be avoided by applying multiple prediction tools to groups of homologous proteins. Here we present ClubSub-P, an online database that combines existing SCL prediction tools into a consensus pipeline from more than 600 proteomes of fully sequenced microorganisms. On top of the consensus prediction at the level of single sequences, the tool uses clusters of homologous proteins from Gram-negative bacteria and from Archaea to eliminate false-positive and false-negative predictions. ClubSub-P can assign the SCL of proteins from Gram-negative bacteria and Archaea with high precision. The database is searchable, and can easily be expanded using either new bacterial genomes or new prediction tools as they become available. This will further improve the performance of the SCL prediction, as well as the detection of misannotated start codons and other annotation errors. ClubSub-P is available online at http://toolkit.tuebingen.mpg.de/clubsubp/ PMID:22073040
Frequency of false-negative reactions to the fragrance mix.
de Groot, A C; van der Kley, A M; Bruynzeel, D P; Meinardi, M M; Smeenk, G; van Joost, T; Pavel, S
1993-03-01
To estimate the frequency of false-negative reactions to the fragrance mix, the 8 constituents of the mix in concentrations of 5% (2% for cinnamic aldehyde) were added to the European standard series for routine testing. Patients with positive reactions to individual ingredients in the absence of a reaction to the mix were retested with serial dilutions. In a 4-month period, 677 patients were tested. 61 (9%) reacted to the mix and to 1 or more of the ingredients. 4 patients (0.6% of all patients tested and 6.2% of the patients allergic to fragrances) had false-negative reactions to the mix. They were allergic to cinnamic alcohol, geraniol, isoeugenol and oak moss (1 reaction each), in the absence of a reaction to the fragrance mix. It is concluded that the currently used concentration of the mix (8 x 1%) not infrequently results in false-negative reactions, and that further research should be done to overcome this problem.
Emotionally Negative Pictures Enhance Gist Memory
Bookbinder, S. H.; Brainerd, C. J.
2016-01-01
In prior work on how true and false memory are influenced by emotion, valence and arousal have often been conflated. Thus, it is difficult to say which specific effects are due to valence and which are due to arousal. In the present research, we used a picture-memory paradigm that allowed emotional valence to be manipulated with arousal held constant. Negatively-valenced pictures elevated both true and false memory, relative to positive and neutral pictures. Conjoint recognition modeling revealed that negative valence (a) reduced erroneous suppression of true memories and (b) increased the familiarity of the semantic content of both true and false memories. Overall, negative valence impaired the verbatim side of episodic memory but enhanced the gist side, and these effects persisted even after a week-long delay. PMID:27454002
Ikeda, Hidetoshi; Abe, Takehiko; Watanabe, Kazuo
2010-04-01
Fifty to eighty percent of Cushing disease is diagnosed by typical endocrine responses. Recently, the number of diagnoses of Cushing disease without typical Cushing syndrome has been increasing; therefore, improving ways to determine the localization of the adenoma and making an early diagnosis is important. This study was undertaken to determine the present diagnostic accuracy for Cushing microadenoma and to compare the differences in diagnostic accuracy between MR imaging and PET/MR imaging. During the past 3 years the authors analyzed the diagnostic accuracy in a series of 35 patients with Cushing adenoma that was verified by surgical pituitary exploration. All 35 cases of Cushing disease, including 20 cases of "overt" and 15 cases of "preclinical" Cushing disease, were studied. Superconductive MR images (1.5 or 3.0 T) and composite images from FDG-PET or methionine (MET)-PET and 3.0-T MR imaging were compared with the localization of adenomas verified by surgery. The diagnostic accuracy of superconductive MR imaging for detecting the localization of Cushing microadenoma was only 40%. The causes of unsatisfactory results for superconductive MR imaging were false-negative results (10 cases), false-positive results (6 cases), and instances of double pituitary adenomas (3 cases). In contrast, the accuracy of microadenoma localization using MET-PET/3.0-T MR imaging was 100% and that of FDG-PET/3.0-T MR imaging was 73%. Moreover, the adenoma location was better delineated on MET-PET/MR images than on FDG-PET/MR images. There was no significant difference in maximum standard uptake value of adenomas evaluated by MET-PET between preclinical Cushing disease and overt Cushing disease. Composite MET-PET/3.0-T MR imaging is useful for the improvement of the delineation of Cushing microadenoma and offers high-quality detectability for early-stage Cushing adenoma.
Epstein, J B; Silverman, S; Epstein, J D; Lonky, S A; Bride, M A
2008-06-01
Conventional visual examination and palpation remains the gold-standard for the identification of oral mucosal lesions. The purpose of this study was to investigate the adjunctive value of a chemiluminescent light source (ViziLite, Zila Pharmaceuticals, Phoenix, Arizona) and application of pharmaceutical grade toluidine blue (TBlue(630), Zila Pharmaceuticals, Phoenix, Arizona) to further assess lesions identified during the conventional oral soft tissue examination. Lesions deemed clinically suspicious by visual examination under incandescent light were further assessed under chemiluminescence and then application of toluidine blue stain. Differences between the conventional visual examination and chemiluminescent examination were noted on four characteristics which may aid in lesion identification. Tissue retention of toluidine blue stain was documented. Each suspicious lesion was biopsied and diagnosed based upon routine histopathology. Both adjunctive exams were evaluated by comparing the histologic diagnosis. The additive value of toluidine blue stain retention was assessed in lesions diagnosed as "serious pathology" defined as severe dysplasia, carcinoma in situ and squamous cell carcinoma. Ninety-seven clinically suspicious lesions in 84 patients were identified. The chemiluminescent exam improved the brightness and/or sharpness of margin in 61.8% of identified lesions. Biopsied lesions with toluidine blue stain retention reduced the false positive rate by 55.26% while maintaining a 100% negative predictive value (NPV). Chemiluminescence was shown to increase the brightness and margins of mucosal lesions in a majority of cases and therefore may assist in identification of mucosal lesions not considered under traditional visual examination. Toluidine blue stain retention was associated with a large reduction in biopsies showing benign histology (false positive biopsy results), while maintaining a 100% NPV for the presence of severe dysplasia or cancer. Practitioners may consider use of these adjuncts in practice, however the results presented are based upon experienced providers in referral centers for mucosal disease or cancer centers and therefore positive findings may be an indication for referral to experienced providers.
Ultrasound-guided synovial Tru-cut biopsy: indications, technique, and outcome in 111 cases.
Sitt, Jacqueline C M; Griffith, James F; Lai, Fernand M; Hui, Mamie; Chiu, K H; Lee, Ryan K L; Ng, Alex W H; Leung, Jason
2017-05-01
To investigate the diagnostic performance of ultrasound-guided synovial biopsy. Clinical notes, pathology and microbiology reports, ultrasound and other imaging studies of 100 patients who underwent 111 ultrasound-guided synovial biopsies were reviewed. Biopsies were compared with the final clinical diagnosis established after synovectomy (n = 43) or clinical/imaging follow-up (n = 57) (mean 30 months). Other than a single vasovagal episode, no complication of synovial biopsy was encountered. One hundred and seven (96 %) of the 111 biopsies yielded synovium histologically. Pathology ± microbiology findings for these 107 conclusive biopsies comprised synovial tumour (n = 30, 28 %), synovial infection (n = 18, 17 %), synovial inflammation (n = 45, 42 %), including gouty arthritis (n = 3), and no abnormality (n = 14, 13 %). The accuracy, sensitivity, and specificity of synovial biopsy was 99 %, 97 %, and 100 % for synovial tumour; 100 %, 100 %, and 100 % for native joint infection; and 78 %, 45 %, and 100 % for prosthetic joint infection. False-negative synovial biopsy did not seem to be related to antibiotic therapy. Ultrasound-guided Tru-cut synovial biopsy is a safe and reliable technique with a high diagnostic yield for diagnosing synovial tumour and also, most likely, for joint infection. Regarding joint infection, synovial biopsy of native joints seems to have a higher diagnostic yield than that for infected prosthetic joints. • Ultrasound-guided Tru-cut synovial biopsy has high accuracy (99 %) for diagnosing synovial tumour. • It has good accuracy, sensitivity, and high specificity for diagnosis of joint infection. • Synovial biopsy of native joints works better than biopsy of prosthetic joints. • A negative synovial biopsy culture from a native joint largely excludes septic arthritis. • Ultrasound-guided Tru-cut synovial biopsy is a safe and well-tolerated procedure.
Varicocelescintigraphy versus X-ray phlebography
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oei, H.Y.; Arndt, J.W.; Mali, W.P.T.
1984-01-01
In this study varicocelescintigraphy (VS) is compared to X-ray phlebography(XP). In 104 patients (pts) suspected for varicocele on physical examination, VS was performed using a large field camera and 5 mCi Tc-99m in-vivo labeled erythrocytes. This was done (without Valsalva) in upright position after taping penis to the abdomen, marking the penisbase and covering the thighs with lead. Twenty 5-sec dynamic images (DY) and 5-min static image (ST) were made. Variocele-size was quantitated by bloodpoolvalue (BPV) using digital image of ST. BPV is the ratio of mean counts/pixel in varicocele and right iliac vessels calculated from adjacent pixels with maximummore » counts. On XP varicocele was diagnosed if the testicular vein was visualized after contrast injection given during Valsalva in the renal vein. In 85 pts varicocele was confirmed on XP. In 67 of them this was recognized easily on both DY and ST; the DY shows activity in the varicocele 10-35 sec later than the iliac artery and the ST shows pooling of activity below the penisbase. In 11 pts the varicocele was only seen on ST and in other 5 pts only on DY. In the remaining 2 pts both DY and ST were false negative. The BPV in 72 pts with abnormal DY and in 11 pts with normal DY varied between 0.4 - 2.2(0.89 +- 0.38) resp. 0.4 - 1.0(0.61 +- 0.19). In 16 of the 19 pts who showed no varicocele on XP, VS also was negative; their BPV varied between 0.2 - 0.4(0.30 +- 0.08). However, in 3 pts who initially had a normal XP, varicocele was diagnosed on both DY and ST, which was confirmed when XP was repeated. Diagnosis of varicocele by physical examination is not accurate. VS is suitable for screenings procedure when both DY and ST are obtained. Pts with abnormal DY have larger varicocele than pts with normal DY.« less
Proksch, A L; Unterer, S; Speck, S; Truyen, U; Hartmann, K
2015-06-01
False negative faecal canine parvovirus (CPV) antigen ELISA results in dogs with CPV infection are common, but the factors that lead to these false negative results are still unknown. The aim of this study was to investigate whether dogs with a false negative faecal CPV antigen ELISA result have milder clinical signs and laboratory changes, a lower faecal virus load, higher faecal and serum CPV antibody titres and a faster recovery than dogs with a positive result. Eighty dogs with CPV infection, confirmed by the presence of clinical signs and a positive faecal CPV polymerase chain reaction (PCR), were assigned to two groups according to their faecal antigen ELISA result. Time until presentation, severity of symptoms, laboratory parameters, faecal virus load, faecal and serum antibody titres, and CPV sequencing data were compared between both groups. In 38/80 dogs that were hospitalised until recovery, the time to recovery, mortality, and the course of the disease were compared between dogs with positive and negative faecal antigen ELISA results. Of the 80 dogs included, 41 (51.3%) had a false negative faecal antigen ELISA result. ELISA-negative dogs had a significantly shorter time until presentation, lower frequency of defaecation, lower faecal virus load, and higher serum antibody concentrations than ELISA-positive dogs. Laboratory changes, CPV shedding, and outcomes were not associated with faecal antigen ELISA results. In conclusion, low faecal CPV load and antibodies binding to CPV antigen in faeces are likely to be important reasons for false negative faecal antigen ELISA results. Dogs with clinical signs of CPV infection should be retested by faecal PCR. Copyright © 2015 Elsevier Ltd. All rights reserved.
Effectiveness of rapid prescreening and 10% rescreening in liquid-based Papanicolaou testing.
Currens, Heather S; Nejkauf, Katharine; Wagner, Lynn; Raab, Stephen S
2012-01-01
Although rapid prescreening (RPS) has been shown to be an effective quality control procedure for detecting false-negative conventional Papanicolaou (Pap) tests, RPS has not been widely implemented in the United States. In our laboratory, cytotechnologists performed RPS in 3,567 liquid-based Pap tests: 1,911 SurePath (BD Diagnostics-TriPath, Burlington, NC) preparations that were manually screened and 1,656 ThinPrep Pap tests (Hologic, Bedford, MA) that were imaged using the ThinPrep Imaging System (Hologic). We compared the sensitivity of RPS, 10% rescreening (R-10%), and routine screening (RS). In contrast with previously published findings, we found that RS + RPS did not improve screening sensitivity compared with RS + R-10%. These results support the following hypotheses: (1) Higher baseline RS sensitivity as a result of Pap test diagnoses standardization implemented for quality improvement purposes decreases the performance impact of RPS. (2) R-10% and RPS quality assurance methods detect diagnostic failures caused by different types of cognitive errors.
Escudero, D; Otero, J; Quindós, B; Viña, L
2015-05-01
Transcranial Doppler ultrasound is able to demonstrate cerebral circulatory arrest associated to brain death, being especially useful in sedated patients, or in those in which complete neurological exploration is not possible. Transcranial Doppler ulstrasound is a portable, noninvasive and high-availability technique. Among its limitations, mention must be made of the absence of acoustic windows and false-negative cases. In patients clinically diagnosed with brain death, with open skulls or with anoxia as the cause of death, cerebral blood flow can be observed by ultrasound, since cerebral circulatory arrest is not always synchronized to the clinical diagnosis. The diagnostic rate is therefore time-dependent, and this fact that must be recognized in order to avoid delays in death certification. Despite its limitations, transcranial Doppler ulstrasound helps solve common diagnostic problems, avoids the unnecessary consumption of resources, and can optimize organ harvesting for transplantation. Copyright © 2014 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.
Are quantitative cultures useful in the diagnosis of hospital-acquired pneumonia?
San Pedro, G
2001-02-01
Noninvasive and invasive tests have been developed and studied for their utility in diagnosing and guiding the treatment of hospital-acquired pneumonia, a condition with an inherently high mortality. Early empiric antibiotic treatment has been shown to reduce mortality, so delaying this treatment until test results are available is not justifiable. Furthermore, tailoring therapy based on results of either noninvasive or invasive tests has not been clearly shown to affect morbidity and mortality. This may be related to quantitative limitations of these tests or possibly to a high false-negative rate in patients who receive early antibiotic treatment and may therefore have suppressed bacterial counts. Results of these tests, however, do influence treatment. It is therefore hoped that they may ultimately provide a rational basis for making therapeutic decisions. In the future, outcomes research should be a part of large-scale clinical trials, and noninvasive and invasive tests should be incorporated into the design in an attempt to provide a better understanding of the value of such tests.
Proactive and Retroactive Effects of Negative Suggestion
ERIC Educational Resources Information Center
Brown, Alan S.; Brown, Christine M.; Mosbacher, Joy L.; Dryden, W. Erich
2006-01-01
The negative effects of false information presented either prior to (proactive interference; PI) or following (retroactive interference; RI) true information was examined with word definitions (Experiment 1) and trivia facts (Experiment 2). Participants were explicitly aware of which information was true and false when shown, and true-false…
Naveed, Hania; Abid, Mariam; Hashmi, Atif Ali; Edhi, Muhammad Muzammamil; Sheikh, Ahmareen Khalid; Mudassir, Ghazala; Khan, Amir
2017-01-01
Intraoperative consultation is an important tool for the evaluation of the upper aerodigestive tract (UAT) malignancies. Although frozen section analysis is a preferred method of intra-operative consultation, however in resource limited countries like Pakistan, this facility is not available in most institutes; therefore, we aimed to evaluate the diagnostic accuracy of touch imprint cytology for UAT malignancies using histopathology of the same tissue as gold standard. The study involved 70 cases of UAT lesions operated during the study period. Intraoperatively, after obtaining the fresh biopsy specimen and prior to placing them in fixative, each specimen was imprinted on 4-6 glass slides, fixed immediately in 95% alcohol and stained with Hematoxylin and Eosin stain. After completion of the cytological procedure, the surgical biopsy specimen was processed. The slides of both touch Imprint cytology and histopathology were examined by two consultant histopathologists. The result of touch imprint cytology showed that touch imprint cytology was diagnostic in 68 cases (97.1%), 55 (78.6%) being malignant, 2 cases (2.9%) were suspicious for malignancy, 11 cases (15.7%) were negative for malignancy while 2 cases (2.9%) were false negative. Amongst the 70 cases, 55 cases (78.6%) were malignant showing squamous cell carcinoma in 49 cases (70%), adenoid cystic carcinoma in 2 cases (2.9%), non-Hodgkin lymphoma 2 cases (2.9%), Mucoepidermoid carcinoma 1 case (1.4%), spindle cell sarcoma in 1 case (1.4%). Two cases (2.9%) were suspicious of malignancy showing atypical squamoid cells on touch imprint cytology, while 13 cases (18.6%) were negative for malignancy, which also included 2 false negative cases. The overall diagnostic accuracy of touch imprint cytology came out to be 96.7% with a sensitivity and specificity of 96 and 100%, respectively while PPV and NPV of touch imprint cytology was found to be 100 and 84%, respectively. Our experience in this study has demonstrated that touch imprint cytology provides reliable specific diagnoses and can be used as an adjunct to histopathology, particularly in developing countries, where the facility of frozen section is often not available, since a rapid preliminary diagnosis may help in the surgical management planning.
Raza, Mushahid; Elkhodair, Samer; Zaheer, Asif; Yousaf, Sohail
2013-11-01
A true gold standard to rule out a significant cervical spine injury in subset of blunt trauma patients with altered sensorium is still to be agreed upon. The objective of this study is to determine whether in obtunded adult patients with blunt trauma, a clinically significant injury to the cervical spine be ruled out on the basis of a normal multidetector cervical spine computed tomography. Comprehensive database search was conducted to include all the prospective and retrospective studies on blunt trauma patients with altered sensorium undergoing cervical spine multidetector CT scan as core imaging modality to "clear" the cervical spine. The studies used two main gold standards, magnetic resonance imaging of the cervical spine and/or prolonged clinical follow-up. The data was extracted to report true positive, true negatives, false positives and false negatives. Meta-analysis of sensitivity, specificity, negative and positive predictive values was performed using Meta Analyst Beta 3.13 software. We also performed a retrospective investigation comparing a robust clinical follow-up and/or cervical spine MR findings in 53 obtunded blunt trauma patients, who previously had undergone a normal multidetector CT scan of the cervical spine reported by a radiologist. A total of 10 studies involving 1850 obtunded blunt trauma patients with initial cervical spine CT scan reported as normal were included in the final meta-analysis. The cumulative negative predictive value and specificity of cervical spine CT of the ten studies was 99.7% (99.4-99.9%, 95% confidence interval). The positive predictive value and sensitivity was 93.7% (84.0-97.7%, 95% confidence interval). In the retrospective review of our obtunded blunt trauma patients, none was later diagnosed to have significant cervical spine injury that required a change in clinical management. In a blunt trauma patient with altered sensorium, a normal cervical spine CT scan is conclusive to safely rule out a clinically significant cervical spine injury. The results of this meta-analysis strongly support the removal of cervical precautions in obtunded blunt trauma patient after normal cervical spine computed tomography. Any further imaging like magnetic resonance imaging of the cervical spine should be performed on case-to-case basis. Copyright © 2013 Elsevier Ltd. All rights reserved.
Theory of Mind in Schizophrenia and Asperger’s Syndrome: Relationship with Negative Symptoms
Ozguven, Halise Devrimci; Oner, Ozgur; Baskak, Bora; Oktem, Ferhunde; Olmez, Senay; Munir, Kerim
2014-01-01
Objective Although previous studies have shown that the theory of mind (ToM) ability is impaired in Asperger’s Syndrome (AS) and in schizophrenia, few controlled studies compared the ToM performance between the two disorders. Besides, the relationship between the degree of ToM impairment and symptom dimensions is unclear, and presence of ToM impairment in remitted patients with schizophrenia is controversial. Here, we tested the hypothesis that schizophrenia patients with prominent negative symptoms were closer to AS patients and different than schizophrenia patients without prominent negative symptoms and healthy controls in terms of ToM functioning. Method Fourteen patients with AS, 20 with schizophrenia and 20 healthy controls, matched by age, educational level and IQ scores were enrolled. AS was diagnosed according to the DSM-IV criteria and independently confirmed by two psychiatrists. Schizophrenia patients were diagnosed by the Turkish version of Structured Clinical Interview for DSM-IV Diagnosis (SCID-I) and symptom severity was evaluated with the Scale for the Assessment of Negative and Positive Symptoms. Schizophrenia group consisted of clinically stable patients. The ToM battery included stories to assess first and second order false belief tasks (ToM1 and ToM2). The full-scale IQ, Verbal Comprehension, Freedom from Distractibility and Perceptual Organization scores were assessed by Weschler Adult Intelligence Scale–Revised (WAIS-R). Non-parametric tests were used to compare the neuropsychological performances of the three groups. In order to investigate whether schizophrenia patients with prominent negative symptoms were similar to AS patients, schizophrenia patients were divided into high (Sch-HN) and low (Sch-LN) negative-symptom subgroups by median split. For these four groups (AS, Sch-HN, Sch-LN, and controls) between group comparisons were performed. Correlations between the clinical measures and ToM performance were assessed by Spearman correlation test. Results AS and schizophrenia patients performed significantly worse than controls in the ToM2 task, while the AS group had worse ToM1 performance than both schizophrenia patients and healthy controls. The Sch-HN subgroup had significantly lower ToM2 scores than the Sch-LN patients, and worse ToM1 functioning than the controls. Conclusions These results suggest that clinically stable schizophrenia patients have ToM impairments. Sch-HN group performed comparably poorly as the AS group, while the Sch-LN group was relatively spared. The most profoundly impaired patients with schizophrenia in terms of ToM functioning were represented by those with high negative symptoms (Sch-HN). Similar to AS, as a neurodevelopmental impairment, these patients may not have developed ToM ability, or they may have lost their ToM capacity as a result of a neurodegenerative process during the illness. Supplementary studies using other methods (e.g., neuroimaging, neurophysiology) may highlight the brain regions that are affected differentially in AS and schizophrenia, the relationship of ToM impairments and negative symptoms, and the role of ToM impairments in the neurodevelopmental or neurodegenerative hypothesis of schizophrenia. PMID:25584026
Reducing false negatives in clinical practice: the role of neural network technology.
Mango, L J
1996-10-01
The fact that some cervical smears result in false-negative findings is an unavoidable and unpredictable consequence of the conventional (manual microscopic) method of screening. Errors in the detection and interpretation of abnormality are cited as leading causes of false-negative cytology findings; these are random errors that are not known to correlate with any patient risk factor, which makes the false-negative findings a "silent" threat that is difficult to prevent. Described by many as a labor-intensive procedure, the microscopic evaluation of a cervical smear involves a detailed search among hundreds of thousands of cells on each smear for a possible few that may indicate abnormality. Investigations into causes of false-negative findings preceding the discovery of high-grade lesions found that many smears had very few diagnostic cells that were often very small in size. These small cells were initially overlooked or misinterpreted and repeatedly missed on rescreening. PAPNET testing is designed to supplement conventional screening by detecting abnormal cells that initially may have been missed by microscopic examination. This interactive system uses neural networks, a type of artificial intelligence well suited for pattern recognition, to automate the arduous search for abnormality. The instrument focuses the review of suspicious cells by a trained cytologist. Clinical studies indicate that PAPNET testing is sensitive to abnormality typically missed by conventional screening and that its use as a supplemental test improves the accuracy of screening.
Matt, Laurie; Mozayen, Mohammad; Gress, Todd; Tirona, Maria Tria
2015-01-01
Breast cancer is the most frequently diagnosed malignancy in women in the United States. It is the second most common malignancy to cause death, with approximately 39,000 women dying of breast cancer in the United States in 2013. Triple negative breast cancer is defined as the absence of estrogen, progesterone and human epidermal growth factor receptor 2 receptors. It has been associated with a higher incidence in African American women, a younger age and a more advanced stage at diagnosis, and an inferior overall survival. To recognize the differences of our West Virginia community population when compared to the national average, we conducted a retrospective review of all patients diagnosed with breast cancer from 2000-2012.
Functions of nonsuicidal self-injury in Singapore adolescents: Implications for intervention.
Ong, Say How; Tan, Augustine Chin Yeow; Liang, Wilfred Zhijian
2017-08-01
The functions of nonsuicidal self-injury (NSSI) and DSM-IV-TR diagnoses were examined in a sample of thirty ethnic adolescents followed up in a local child and adolescent psychiatric clinic in Singapore. The most commonly endorsed function of NSSI on the Functional Assessment of Self-Mutilation scale was Automatic Negative Reinforcement (A-NR) and the least being Social Negative Reinforcement (S-NR). Participants were more likely to be diagnosed as having Major Depression Disorder. Depressed adolescents did not differ from non-depressed counterparts in their endorsement of social reinforcement functions. The results suggest that specific psychosocial interventions may help address both automatic and social functions of NSSI in Singapore adolescents. Copyright © 2017 Elsevier B.V. All rights reserved.
Murata, Fernando Henrique Antunes; Ferreira, Marina Neves; Camargo, Natália Sahyoun; Santos, Gabriela Soria; Spegiorin, Lígia Cosentino Junqueira Franco; Silveira-Carvalho, Aparecida Perpétuo; Pereira-Chioccola, Vera Lucia; Mattos, Luiz Carlos de; Mattos, Cinara Cássia Brandão de
2016-01-01
Toxoplasmosis during pregnancy can be severe; thus, it is essential to diagnose the disease via serological tests. An enzyme-linked immunosorbent assay (ELISA) was used to investigate anti-Toxoplasma gondii immunoglobulin A (IgA), M (IgM) and G (IgG) antibodies in 62 high-risk pregnant women. Forty-three (69.4%) women were positive for IgA, 31 (50%) for IgG, and 57 (91.9%) for IgM; 4 (6,5%) were positive for IgA but negative for IgM; 10 (16.1%) were negative for IgA and IgM but positive for IgG. Testing for these antibodies can help diagnose infection in pregnant women, thereby contributing to clinical management.
Aktar, Evin; Bögels, Susan M
2017-12-01
Depression and anxiety load in families. In the present study, we focus on exposure to parental negative emotions in first postnatal year as a developmental pathway to early parent-to-child transmission of depression and anxiety. We provide an overview of the little research available on the links between infants' exposure to negative emotion and infants' emotional development in this developmentally sensitive period, and highlight priorities for future research. To address continuity between normative and maladaptive development, we discuss exposure to parental negative emotions in infants of parents with as well as without depression and/or anxiety diagnoses. We focus on infants' emotional expressions in everyday parent-infant interactions, and on infants' attention to negative facial expressions as early indices of emotional development. Available evidence suggests that infants' emotional expressions echo parents' expressions and reactions in everyday interactions. In turn, infants exposed more to negative emotions from the parent seem to attend less to negative emotions in others' facial expressions. The links between exposure to parental negative emotion and development hold similarly in infants of parents with and without depression and/or anxiety diagnoses. Given its potential links to infants' emotional development, and to later psychological outcomes in children of parents with depression and anxiety, we conclude that early exposure to parental negative emotions is an important developmental mechanism that awaits further research. Longitudinal designs that incorporate the study of early exposure to parents' negative emotion, socio-emotional development in infancy, and later psychological functioning while considering other genetic and biological vulnerabilities should be prioritized in future research.
ERIC Educational Resources Information Center
Lonigan, Christopher J.; And Others
1994-01-01
Examined self-reported depression and anxiety in 233 inpatient children diagnosed with anxiety disorder or depressive disorder. Depressed children reported more problems related to loss of interest and low motivation and had more negative view of themselves. Anxious children reported more worry about future, their well-being, and reactions of…
Breast cancer is the second most common cancer in women living in the United States, with triple-negative breast cancer (TNBC) accounting for approximately 15% of diagnoses. While chemotherapy is the standard-of-care in TNBC, resistance is common and associated with poor prognosis.
Standoff detection of chemical and biological threats using laser-induced breakdown spectroscopy.
Gottfried, Jennifer L; De Lucia, Frank C; Munson, Chase A; Miziolek, Andrzej W
2008-04-01
Laser-induced breakdown spectroscopy (LIBS) is a promising technique for real-time chemical and biological warfare agent detection in the field. We have demonstrated the detection and discrimination of the biological warfare agent surrogates Bacillus subtilis (BG) (2% false negatives, 0% false positives) and ovalbumin (0% false negatives, 1% false positives) at 20 meters using standoff laser-induced breakdown spectroscopy (ST-LIBS) and linear correlation. Unknown interferent samples (not included in the model), samples on different substrates, and mixtures of BG and Arizona road dust have been classified with reasonable success using partial least squares discriminant analysis (PLS-DA). A few of the samples tested such as the soot (not included in the model) and the 25% BG:75% dust mixture resulted in a significant number of false positives or false negatives, respectively. Our preliminary results indicate that while LIBS is able to discriminate biomaterials with similar elemental compositions at standoff distances based on differences in key intensity ratios, further work is needed to reduce the number of false positives/negatives by refining the PLS-DA model to include a sufficient range of material classes and carefully selecting a detection threshold. In addition, we have demonstrated that LIBS can distinguish five different organophosphate nerve agent simulants at 20 meters, despite their similar stoichiometric formulas. Finally, a combined PLS-DA model for chemical, biological, and explosives detection using a single ST-LIBS sensor has been developed in order to demonstrate the potential of standoff LIBS for universal hazardous materials detection.
Studies regarding the mechanism of false negative urea breath tests with proton pump inhibitors.
Graham, David Y; Opekun, Antone R; Hammoud, Fadi; Yamaoka, Yoshio; Reddy, Rita; Osato, Michael S; El-Zimaity, Hala M T
2003-05-01
The mechanism of false negative urea breath tests (UBTs) results among proton pump inhibitor (PPI) users is unknown. We studied the time course of PPI-associated negative UBT, the relation to Helicobacter pylori density, and whether gastric acidification would prevent false negative UBT results. In the UBT experiment, H. pylori-infected volunteers received omeprazole 20 mg b.i.d. for 13.5 days. UBTs with citric acid were done before, after 6.5 days of PPI, and 1, 2, 4, 7, and 14 days after therapy. In the culture and histology experiment, after a wash-out of >5 months, nine of the original subjects were rechallenged with omeprazole for 6.5 days. Antral and corpus biopsies for histology and culture were done before and 1 day after PPI administration. Thirty subjects (mean age 42 yr) were enrolled. UBTs were significantly reduced on day 6.5 (p = 0.031); 10 subjects (33%) developed transient negative UBTs. The UBT recovered in all but one subject by the fourth day post-PPI and in all subjects by day 14. In the culture and histology experiment, upon PPI rechallenge, three of nine subjects (33%) had negative UBTs. H. pylori density, whether measured by culture or histology, decreased with PPI therapy; antral biopsies became histologically negative in five subjects and corpus biopsies in three subjects. PPI-induced negative UBT results were related to the anti-H. pylori effect of the PPI. Acidification of the stomach did not prevent false negative UBT results. Three days is likely the minimum delay from stopping PPI until one should perform a test for active infection. A delay of 14 days is preferred.
The Diagnostic Accuracy of Cytology for the Diagnosis of Hepatobiliary and Pancreatic Cancers.
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.
Ganière, Vincent; Domenichini, Giulia; Niculescu, Viviana; Cassagneau, Romain; Defaye, Pascal; Burri, Haran
2013-03-01
The prerequisite for cardiac resynchronization therapy (CRT) is ventricular capture, which may be verified by analysis of the surface electrocardiogram (ECG). Few algorithms exist to diagnose loss of ventricular capture. Electrocardiograms from 126 CRT patients were analysed during biventricular (BV), right ventricular (RV), and left ventricular (LV) pacing. An algorithm evaluating QRS narrowing in the limb leads and increasing negativity in lead I to diagnose changes in ventricular capture was devised, prospectively validated, and compared with two existing algorithms. Performance of the algorithm according to ventricular lead position was also assessed. Our algorithm had an accuracy of 88% to correctly identify the changes in ventricular capture (either loss or gain of RV or LV capture). The algorithm had a sensitivity of 94% and a specificity of 96% with an accuracy of 96% for identifying loss of LV capture (the most clinically relevant change), and compared favourably with the existing algorithms. Performance of the algorithms was not significantly affected by RV or LV lead position. A simple two-step algorithm evaluating QRS width in the limb leads and changes in negativity in lead I can accurately diagnose the lead responsible for intermittent loss of ventricular capture in CRT. This simple tool may be of particular use outside the setting of specialized device clinics.
Kaufmann, Ronnie; Blum, Shlomo E; Elad, Daniel; Zur, Gila
2016-08-01
Point-of-care Dermatophyte Test Medium (PoC-DTM) is a diagnostic procedure to rule in/rule out dermatophytosis in veterinary clinics. To evaluate the performance of PoC-DTM in the clinic compared to DTM plate culture in a mycology laboratory and to compare results obtained by general practitioners and referral clinicians. Hair samples were collected from 47 cats and 54 dogs with suspected dermatophytosis and from nine healthy controls (seven cats and two dogs). This was a multicentre blinded study. In one group (65 suspected cases, 9 healthy controls), PoC-DTM results were evaluated by clinicians in a referral clinic (SP group) who examined the colony morphology macroscopically and microscopically. In the other group (36 suspected cases) PoC-DTM results were evaluated by clinicians from general practice for colour change only, with no macroscopic or microscopic examination (GP group). All hair samples were also cultured on DTM plates in a mycology laboratory. Laboratory culture was considered the gold standard for comparison. Agreements between tests were 97% (two false positive; κ = 0.839) and 80.6% (five false positives and two false negatives; κ = 0.466) in the SP and GP groups, respectively. This difference between groups was significant (P = 0.024). When applying macroscopic and microscopic evaluation of the colony, PoC-DTM is accurate for diagnosing dermatophytes with only a 3% chance of error. However, when macroscopic and microscopic examination is not included there is significant (19.4%) chance for an incorrect diagnosis. © 2016 ESVD and ACVD.
Emotionally negative pictures enhance gist memory.
Bookbinder, S H; Brainerd, C J
2017-02-01
In prior work on how true and false memory are influenced by emotion, valence and arousal have often been conflated. Thus, it is difficult to say which specific effects are caused by valence and which are caused by arousal. In the present research, we used a picture-memory paradigm that allowed emotional valence to be manipulated with arousal held constant. Negatively valenced pictures elevated both true and false memory, relative to positive and neutral pictures. Conjoint recognition modeling revealed that negative valence (a) reduced erroneous suppression of true memories and (b) increased the familiarity of the semantic content of both true and false memories. Overall, negative valence impaired the verbatim side of episodic memory but enhanced the gist side, and these effects persisted even after a week-long delay. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Mood-congruent false memories persist over time.
Knott, Lauren M; Thorley, Craig
2014-01-01
In this study, we examined the role of mood-congruency and retention interval on the false recognition of emotion laden items using the Deese/Roediger-McDermott (DRM) paradigm. Previous research has shown a mood-congruent false memory enhancement during immediate recognition tasks. The present study examined the persistence of this effect following a one-week delay. Participants were placed in a negative or neutral mood, presented with negative-emotion and neutral-emotion DRM word lists, and administered with both immediate and delayed recognition tests. Results showed that a negative mood state increased remember judgments for negative-emotion critical lures, in comparison to neutral-emotion critical lures, on both immediate and delayed testing. These findings are discussed in relation to theories of spreading activation and emotion-enhanced memory, with consideration of the applied forensic implications of such findings.
Deep learning aided decision support for pulmonary nodules diagnosing: a review.
Yang, Yixin; Feng, Xiaoyi; Chi, Wenhao; Li, Zhengyang; Duan, Wenzhe; Liu, Haiping; Liang, Wenhua; Wang, Wei; Chen, Ping; He, Jianxing; Liu, Bo
2018-04-01
Deep learning techniques have recently emerged as promising decision supporting approaches to automatically analyze medical images for different clinical diagnosing purposes. Diagnosing of pulmonary nodules by using computer-assisted diagnosing has received considerable theoretical, computational, and empirical research work, and considerable methods have been developed for detection and classification of pulmonary nodules on different formats of images including chest radiographs, computed tomography (CT), and positron emission tomography in the past five decades. The recent remarkable and significant progress in deep learning for pulmonary nodules achieved in both academia and the industry has demonstrated that deep learning techniques seem to be promising alternative decision support schemes to effectively tackle the central issues in pulmonary nodules diagnosing, including feature extraction, nodule detection, false-positive reduction, and benign-malignant classification for the huge volume of chest scan data. The main goal of this investigation is to provide a comprehensive state-of-the-art review of the deep learning aided decision support for pulmonary nodules diagnosing. As far as the authors know, this is the first time that a review is devoted exclusively to deep learning techniques for pulmonary nodules diagnosing.
Ruling out Pulmonary Embolism in Patients with High Pretest Probability.
Akhter, Murtaza; Kline, Jeffrey; Bhattarai, Bikash; Courtney, Mark; Kabrhel, Christopher
2018-05-01
The American College of Emergency Physicians guidelines recommend more aggressive workup beyond imaging alone in patients with a high pretest probability (PTP) of pulmonary embolism (PE). However, the ability of multiple tests to safely rule out PE in high PTP patients is not known. We sought to measure the ability of negative computed tomography pulmonary angiography (CTPA) along with negative D-dimer to rule out PE in these high-risk patients. We analyzed data from a previous prospective observational study conducted in 12 emergency departments (ED). Wells score criteria were entered by providers before final PE testing. PE was diagnosed by imaging on the index ED visit, or within 45 days, demonstrating either PE or deep vein thrombosis (DVT), or if the patient died of PE during the 45-day, follow-up period. Testing threshold was set at 1.8%. A total of 7,940 patients were enrolled and tested for PE, and 257 had high PTP (Wells >6). Sixteen of these high-risk patients had negative CTPA and negative D-dimer, of whom two were positive for PE (12.5% [95% confidence interval {2.2%-40.0%}]). One of these patients had a DVT on CT venogram and the other was diagnosed at follow-up. Our analysis suggests that in patients with high PTP of PE, neither negative CTPA by itself nor a negative CTPA plus a negative D-dimer are sufficient to rule out PE. More aggressive workup strategies may be required for these patients.
Negative Symptoms and Avoidance of Social Interaction: A Study of Non-Verbal Behaviour.
Worswick, Elizabeth; Dimic, Sara; Wildgrube, Christiane; Priebe, Stefan
2018-01-01
Non-verbal behaviour is fundamental to social interaction. Patients with schizophrenia display an expressivity deficit of non-verbal behaviour, exhibiting behaviour that differs from both healthy subjects and patients with different psychiatric diagnoses. The present study aimed to explore the association between non-verbal behaviour and symptom domains, overcoming methodological shortcomings of previous studies. Standardised interviews with 63 outpatients diagnosed with schizophrenia were videotaped. Symptoms were assessed using the Clinical Assessment Interview for Negative Symptoms (CAINS), the Positive and Negative Syndrome Scale (PANSS) and the Calgary Depression Scale. Independent raters later analysed the videos for non-verbal behaviour, using a modified version of the Ethological Coding System for Interviews (ECSI). Patients with a higher level of negative symptoms displayed significantly fewer prosocial (e.g., nodding and smiling), gesture, and displacement behaviours (e.g., fumbling), but significantly more flight behaviours (e.g., looking away, freezing). No gender differences were found, and these associations held true when adjusted for antipsychotic medication dosage. Negative symptoms are associated with both a lower level of actively engaging non-verbal behaviour and an increased active avoidance of social contact. Future research should aim to identify the mechanisms behind flight behaviour, with implications for the development of treatments to improve social functioning. © 2017 S. Karger AG, Basel.
The effect of mood on false memory for emotional DRM word lists.
Zhang, Weiwei; Gross, Julien; Hayne, Harlene
2017-04-01
In the present study, we investigated the effect of participants' mood on true and false memories of emotional word lists in the Deese-Roediger-McDermott (DRM) paradigm. In Experiment 1, we constructed DRM word lists in which all the studied words and corresponding critical lures reflected a specified emotional valence. In Experiment 2, we used these lists to assess mood-congruent true and false memory. Participants were randomly assigned to one of three induced-mood conditions (positive, negative, or neutral) and were presented with word lists comprised of positive, negative, or neutral words. For both true and false memory, there was a mood-congruent effect in the negative mood condition; this effect was due to a decrease in true and false recognition of the positive and neutral words. These findings are consistent with both spreading-activation and fuzzy-trace theories of DRM performance and have practical implications for our understanding of the effect of mood on memory.
Positive events protect children from causal false memories for scripted events.
Melinder, Annika; Toffalini, Enrico; Geccherle, Eleonora; Cornoldi, Cesare
2017-11-01
Adults produce fewer inferential false memories for scripted events when their conclusions are emotionally charged than when they are neutral, but it is not clear whether the same effect is also found in children. In the present study, we examined this issue in a sample of 132 children aged 6-12 years (mean 9 years, 3 months). Participants encoded photographs depicting six script-like events that had a positively, negatively, or a neutral valenced ending. Subsequently, true and false recognition memory of photographs related to the observed scripts was tested as a function of emotionality. Causal errors-a type of false memory thought to stem from inferential processes-were found to be affected by valence: children made fewer causal errors for positive than for neutral or negative events. Hypotheses are proposed on why adults were found protected against inferential false memories not only by positive (as for children) but also by negative endings when administered similar versions of the same paradigm.
Myocardial infarction false alarm: initial electrocardiogram and cardiac enzymes.
Gupta, Esha Das; Sakthiswary, Rajalingham
2014-05-01
The objectives of this study were to determine the incidence of a myocardial infarction "false alarm" and evaluate the efficacy of the initial electrocardiogram and cardiac enzymes in diagnosing myocardial infarction in Malaysia. We recruited patients who were admitted with suspected myocardial infarction from June to August 2008. The medical records of these patients were reviewed for the initial electrocardiogram, initial cardiac enzyme levels (creatinine kinase-MB and troponin T), and the final diagnosis upon discharge. The subjects were stratified into 2 groups: true myocardial infarction, and false alarm. 125 patients were enrolled in this study. Following admission and further evaluation, the diagnosis was revised from myocardial infarction to other medical conditions in 48 (38.4%) patients. The sensitivity and specificity of the initial ischemic electrocardiographic changes were 54.5% and 70.8%, respectively. Raised cardiac enzymes had a sensitivity of 44.3% and specificity of 95.8%. A significant proportion of patients in Malaysia are admitted with a false-alarm myocardial infarction. The efficacy of the electrocardiogram in diagnosing myocardial infarction in Malaysia was comparable to the findings of Western studies, but the cardiac enzymes had a much lower sensitivity.
False Memories for Affective Information in Schizophrenia.
Fairfield, Beth; Altamura, Mario; Padalino, Flavia A; Balzotti, Angela; Di Domenico, Alberto; Mammarella, Nicola
2016-01-01
Studies have shown a direct link between memory for emotionally salient experiences and false memories. In particular, emotionally arousing material of negative and positive valence enhanced reality monitoring compared to neutral material since emotional stimuli can be encoded with more contextual details and thereby facilitate the distinction between presented and imagined stimuli. Individuals with schizophrenia appear to be impaired in both reality monitoring and memory for emotional experiences. However, the relationship between the emotionality of the to-be-remembered material and false memory occurrence has not yet been studied. In this study, 24 patients and 24 healthy adults completed a false memory task with everyday episodes composed of 12 photographs that depicted positive, negative, or neutral outcomes. Results showed how patients with schizophrenia made a higher number of false memories than normal controls ( p < 0.05) when remembering episodes with positive or negative outcomes. The effect of valence was apparent in the patient group. For example, it did not affect the production causal false memories ( p > 0.05) resulting from erroneous inferences but did interact with plausible, script consistent errors in patients (i.e., neutral episodes yielded a higher degree of errors than positive and negative episodes). Affective information reduces the probability of generating causal errors in healthy adults but not in patients suggesting that emotional memory impairments may contribute to deficits in reality monitoring in schizophrenia when affective information is involved.
Fairfield, Beth; Mammarella, Nicola; Di Domenico, Alberto; D'Aurora, Marco; Stuppia, Liborio; Gatta, Valentina
2017-08-30
False memories are common memory distortions in everyday life and seem to increase with affectively connoted complex information. In line with recent studies showing a significant interaction between the noradrenergic system and emotional memory, we investigated whether healthy volunteer carriers of the deletion variant of the ADRA2B gene that codes for the α2b-adrenergic receptor are more prone to false memories than non-carriers. In this study, we collected genotype data from 212 healthy female volunteers; 91 ADRA2B carriers and 121 non-carriers. To assess gene effects on false memories for affective information, factorial mixed model analysis of variances (ANOVAs) were conducted with genotype as the between-subjects factor and type of memory error as the within-subjects factor. We found that although carriers and non-carriers made comparable numbers of false memory errors, they showed differences in the direction of valence biases, especially for inferential causal errors. Specifically, carriers produced fewer causal false memory errors for scripts with a negative outcome, whereas non-carriers showed a more general emotional effect and made fewer causal errors with both positive and negative outcomes. These findings suggest that putatively higher levels of noradrenaline in deletion carriers may enhance short-term consolidation of negative information and lead to fewer memory distortions when facing negative events. Copyright © 2017 Elsevier B.V. All rights reserved.
False Memories for Affective Information in Schizophrenia
Fairfield, Beth; Altamura, Mario; Padalino, Flavia A.; Balzotti, Angela; Di Domenico, Alberto; Mammarella, Nicola
2016-01-01
Studies have shown a direct link between memory for emotionally salient experiences and false memories. In particular, emotionally arousing material of negative and positive valence enhanced reality monitoring compared to neutral material since emotional stimuli can be encoded with more contextual details and thereby facilitate the distinction between presented and imagined stimuli. Individuals with schizophrenia appear to be impaired in both reality monitoring and memory for emotional experiences. However, the relationship between the emotionality of the to-be-remembered material and false memory occurrence has not yet been studied. In this study, 24 patients and 24 healthy adults completed a false memory task with everyday episodes composed of 12 photographs that depicted positive, negative, or neutral outcomes. Results showed how patients with schizophrenia made a higher number of false memories than normal controls (p < 0.05) when remembering episodes with positive or negative outcomes. The effect of valence was apparent in the patient group. For example, it did not affect the production causal false memories (p > 0.05) resulting from erroneous inferences but did interact with plausible, script consistent errors in patients (i.e., neutral episodes yielded a higher degree of errors than positive and negative episodes). Affective information reduces the probability of generating causal errors in healthy adults but not in patients suggesting that emotional memory impairments may contribute to deficits in reality monitoring in schizophrenia when affective information is involved. PMID:27965600
Sentinel lymph node biopsy for early oral cancers: Westmead Hospital experience.
Abdul-Razak, Muzib; Chung, Hsiang; Wong, Eva; Palme, Carsten; Veness, Michael; Farlow, David; Coleman, Hedley; Morgan, Gary
2017-01-01
Sentinel lymph node biopsy (SLNB) has become an alternative option to elective neck dissection (END) for early oral cavity squamous cell carcinoma (OCSCC) outside of Australia. We sought to assess the technical feasibility of SLNB and validate its accuracy against that of END in an Australian setting. We performed a prospective cohort study consisting of 30 consecutive patients with cT 1 - 2 N 0 OCSCC referred to the Head and Neck Cancer Service, Westmead Hospital, Sydney, between 2011 and 2014. All patients underwent SLNB followed by immediate selective neck dissection (levels I-III). A total of 30 patients were diagnosed with an early clinically node-negative OCSCC (seven cT1 and 23 cT2), with the majority located on the oral tongue. A median of three (range: 1-14) sentinel nodes were identified on lymphoscintigraphy, and all sentinel nodes were successfully retrieved, with 50% having a pathologically positive sentinel node. No false-negative sentinel nodes were identified using selective neck dissection as the gold standard. The negative predictive value (NPV) of SLNB was 100%, with 40% having a sentinel node identified outside the field of planned neck dissection on lymphoscintigraphy. Of these, one patient had a positive sentinel node outside of the ipsilateral supraomohyoid neck dissection template. SLNB for early OCSCC is technically feasible in an Australian setting. It has a high NPV and can potentially identify at-risk lymphatic basins outside the traditional selective neck dissection levels even in well-lateralized lesions. © 2016 Royal Australasian College of Surgeons.
Stirling, Paul; Tahir, Mohammed; Atkinson, Henry Dushan
2017-03-29
Rapid diagnosis of septic arthritis from Gram-stain microscopy is limited by an inherent false-negative rate of 25-78%. The presence of concomitant crystal arthritis in 5% of cases represents a particular diagnostic challenge. This study aims to investigate the effects that a concomitant crystal arthropathy have on the ability of Gram-stain microscopy of synovial fluid to diagnose a septic arthritis. This is a 12-year retrospective cohort study. Inclusion criteria were a positive synovial fluid culture result with a positive clinical diagnosis of septic arthritis. Results were correlated with presence or absence of urate and calcium pyrophosphate crystals, and Gram-stain result. During this time our collection and analysis methods remained unchanged. All samples were collected in Lithium Heparin containers. Chi-squared test with a p value < 0.05 was considered significant. 602 synovial fluid samples were included. 162 cases of concomitant crystal arthritis were identified (27%). Of these, 16 (10%) had an initial negative Gram-stain. Of the 440 samples with no crystals detected, 18 (4%) had an initial negative Gram-stain microscopy result (p < 0.05). The incidence of concurrent septic and crystal arthritis may be higher than previously thought. Synovial fluid samples in concomitant septic and crystal arthritis are significantly less likely to have a positive Gram-stain at microscopy than in cases of an isolated septic arthritis. We would advise the clinician to maintain a high index of suspicion for septic arthritis in these patients. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
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®
[Differential diagnosis of Dandy-Walker syndrome different presentations].
Tobías-González, Pablo; Gil Mira, Mar; Valero de Bernabé, Javier; Zapardiel, Ignacio
2012-08-01
Dandy-Walker syndrome is a set of abnormalities of the posterior fossa including three modalities: classic Dandy-Walker malformation, Dandy-Walker variant and mega-cisterna magna. Our objective is clarify the differential diagnosis among these entities. Descriptive and retrospective study of Dandy-Walker cases diagnosed at our Department during the last five years plus a review of the related Medical literature. Three cases of Dandy-Walker modalities are reported: one case of classic Dandy-Walker malformation, one case of Dandy-Walker variant, and one case of false Dandy-Walker. In the first two cases the patients underwent legal abortion, whereas in the last one a healthy male newborn was delivered in the week 38 of gestation. Malformations in the posterior fossa, including Dandy-Walker syndrome, are still a challenge in prenatal diagnosis. Technical developments in imaging, such as in three-dimensional sonography and magnetic resonance, allow higher resolution and multiplanar images for an easier diagnose. There is a high rate of false positive, particularly before the 18th week of gestation. It is advisable not to establish a final diagnose before that week.
Junghans-Rutelonis, Ashley N; Tackett, Alayna P; Suorsa, Kristina I; Chaney, John M; Mullins, Larry L
2018-01-01
The present study examined the impact of asthma-specific thought intrusion (TI) and thought suppression (TS) on two cognitive-affective variables (self-focused attention and fear of negative evaluation) among adolescents and young adults (AYAs) diagnosed with childhood-onset asthma. Participants were 290 AYAs who completed assessment questionnaires and participated in a written exercise electronically. Asthma-TI and TS were reported by participants following participation in a writing assignment. Asthma-TI was associated with increased private, public, and social anxiety self-focused attention, and greater fear of negative evaluation. Interestingly, asthma-TS was not associated with these same outcome variables. Findings suggest illness-specific cognitions are associated with cognitive-affective variables and it may be important to assess for illness-specific intrusive thoughts following asthma-focused medical appointments. Additionally, findings suggest the importance of assessing asthma-TI and TS separately in order to better understand thoughts about health and psychological functioning.
Dupouy, Julie; Vergnes, Aurore; Laporte, Catherine; Kinouani, Shérazade; Auriacombe, Marc; Oustric, Stéphane; Rougé Bugat, Marie-Eve
2018-12-01
High levels of stigma towards patients with substance use disorder (SUD) have been found in health professionals and medical students. To assess the capability of residents in general practice to diagnose SUD correctly; to assess their stigmatization of patients with SUD and to assess the correlation between both variables. We hypothesized a negative correlation. In 2014, we conducted a cross-sectional survey among French residents in general practice, using a self-administered questionnaire. First, a clinical case of SUD (tramadol) was presented, to assess the diagnosis and retained diagnostic criteria. A second clinical vignette was presented (intravenous heroin user) to assess stigmatization with the Attitudes to Mental Illness Questionnaire (AMIQ). Its score ranges from -10 (negative attitude) to +10 (positive attitude). AMIQ scores of residents who diagnosed SUD correctly versus incorrectly, and who had received at least six hours versus less than six hours of teaching on this topic, were compared using Student's t-test. Of 1284 solicited residents, 303 participated (23.6%), 249 residents diagnosed SUD correctly (82.2%). The mean AMIQ score was -3.91 (SD 2.4) without significant difference regarding the correct diagnosis of SUD; but with a significant difference between residents who had received training in SUD for at least six hours versus residents less trained (AMIQ scores -3.76 (SD 2.46) versus -4.50 (SD 2.27), p = .0354). Residents in general practice had a good capacity to diagnose SUD correctly but on average expressed negative attitudes toward people with SUD. More SUD teaching seems to help in reducing stigmatizing attitudes.
Why patients' disruptive behaviours impair diagnostic reasoning: a randomised experiment.
Mamede, Sílvia; Van Gog, Tamara; Schuit, Stephanie C E; Van den Berge, Kees; Van Daele, Paul L A; Bueving, Herman; Van der Zee, Tim; Van den Broek, Walter W; Van Saase, Jan L C M; Schmidt, H G
2017-01-01
Patients who display disruptive behaviours in the clinical encounter (the so-called 'difficult patients') may negatively affect doctors' diagnostic reasoning, thereby causing diagnostic errors. The present study aimed at investigating the mechanisms underlying the negative influence of difficult patients' behaviours on doctors' diagnostic performance. A randomised experiment with 74 internal medicine residents. Doctors diagnosed eight written clinical vignettes that were exactly the same except for the patients' behaviours (either difficult or neutral). Each participant diagnosed half of the vignettes in a difficult patient version and the other half in a neutral version in a counterbalanced design. After diagnosing each vignette, participants were asked to recall the patient's clinical findings and behaviours. Main measurements were: diagnostic accuracy scores; time spent on diagnosis, and amount of information recalled from patients' clinical findings and behaviours. Mean diagnostic accuracy scores (range 0-1) were significantly lower for difficult than neutral patients' vignettes (0.41 vs 0.51; p<0.01). Time spent on diagnosing was similar. Participants recalled fewer clinical findings (mean=29.82% vs mean=32.52%; p<0.001) and more behaviours (mean=25.51% vs mean=17.89%; p<0.001) from difficult than from neutral patients. Difficult patients' behaviours induce doctors to make diagnostic errors, apparently because doctors spend part of their mental resources on dealing with the difficult patients' behaviours, impeding adequate processing of clinical findings. Efforts should be made to increase doctors' awareness of the potential negative influence of difficult patients' behaviours on diagnostic decisions and their ability to counteract such influence. 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/.
Rhabdomyosarcoma: Current Challenges and Their Implications for Developing Therapies
Hettmer, Simone; Li, Zhizhong; Billin, Andrew N.; Barr, Frederic G.; Cornelison, D.D.W.; Ehrlich, Alan R.; Guttridge, Denis C.; Hayes-Jordan, Andrea; Helman, Lee J.; Houghton, Peter J.; Khan, Javed; Langenau, David M.; Linardic, Corinne M.; Pal, Ranadip; Partridge, Terence A.; Pavlath, Grace K.; Rota, Rossella; Schäfer, Beat W.; Shipley, Janet; Stillman, Bruce; Wexler, Leonard H.; Wagers, Amy J.; Keller, Charles
2014-01-01
Rhabdomyosarcoma (RMS) represents a rare, heterogeneous group of mesodermal malignancies with skeletal muscle differentiation. One major subgroup of RMS tumors (so-called “fusion-positive” tumors) carries exclusive chromosomal translocations that join the DNA-binding domain of the PAX3 or PAX7 gene to the transactivation domain of the FOXO1 (previously known as FKHR) gene. Fusion-negative RMS represents a heterogeneous spectrum of tumors with frequent RAS pathway activation. Overtly metastatic disease at diagnosis is more frequently found in individuals with fusion-positive than in those with fusion-negative tumors. RMS is the most common pediatric soft-tissue sarcoma, and approximately 60% of all children and adolescents diagnosed with RMS are cured by currently available multimodal therapies. However, a curative outcome is achieved in <30% of high-risk individuals with RMS, including all those diagnosed as adults, those diagnosed with fusion-positive tumors during childhood (including metastatic and nonmetastatic tumors), and those diagnosed with metastatic disease during childhood (including fusion-positive and fusion-negative tumors). This white paper outlines current challenges in RMS research and their implications for developing more effective therapies. Urgent clinical problems include local control, systemic disease, need for improved risk stratification, and characterization of differences in disease course in children and adults. Biological challenges include definition of the cellular functions of PAX-FOXO1 fusion proteins, clarification of disease heterogeneity, elucidation of the cellular origins of RMS, delineation of the tumor microenvironment, and identification of means for rational selection and testing of new combination therapies. To streamline future therapeutic developments, it will be critical to improve access to fresh tumor tissue for research purposes, consider alternative trial designs to optimize early clinical testing of candidate drugs, coalesce advocacy efforts to garner public and industry support, and facilitate collaborative efforts between academia and industry. PMID:25368019
Azoulay, Elie; Guigue, Nicolas; Darmon, Michael; Mokart, Djamel; Lemiale, Virginie; Kouatchet, Achille; Mayaux, Julien; Vincent, François; Nyunga, Martine; Bruneel, Fabrice; Rabbat, Antoine; Bretagne, Stéphane; Lebert, Christine; Meert, Anne-Pascale; Benoit, Dominique; Pene, Frédéric
2016-04-19
Invasive fungal infections (IFIs) are life-threatening complications of hematological malignancies that must be diagnosed early to allow effective treatment. Few data are available on the performance of serum (1-3)-β-D-glucan (BG) assays for diagnosing IFI in patients with hematological malignancies admitted to the intensive care unit (ICU). In this study, 737 consecutive patients with hematological malignancies admitted to 17 ICUs routinely underwent a BG assay at ICU admission. IFIs were diagnosed using standard criteria applied by three independent specialists. Among the 737 patients, 439 (60%) required mechanical ventilation and 273 (37%) died before hospital discharge. Factors known to alter BG concentrations were identified in most patients. IFIs were documented in 78 (10.6%) patients (invasive pulmonary aspergillosis, n = 54; Pneumocystis jirovecii pneumonia, n = 13; candidemia, n = 13; and fusarium infections, n = 3). BG concentrations (pg/mL) were higher in patients with than without IFI (144 (77-510) vs. 50 (30-125), < 0.0001). With 80 pg/mL as the cutoff, sensitivity was 72%, specificity 65%, and area-under-the-curve 0.74 (0.68-0.79). Assuming a prevalence of 10%, the negative and positive predictive values were 94% and 21%. By multivariable analysis, factors independently associated with BG > 80 pg/mL were IFI, admission SOFA score, autologous bone-marrow or hematopoietic stem-cell transplantation, and microbiologically documented bacterial infection. In conclusion, in unselected critically ill hematology patients with factors known to affect serum BG, this biomarker showed only moderate diagnostic performance and rarely detected IFI. However, the negative predictive value was high. Studies are needed to assess whether a negative BG test indicates that antifungal de-escalation is safe.
Azoulay, Elie; Guigue, Nicolas; Darmon, Michael; Mokart, Djamel; Lemiale, Virginie; Kouatchet, Achille; Mayaux, Julien; Vincent, François; Nyunga, Martine; Bruneel, Fabrice; Rabbat, Antoine; Bretagne, Stéphane; Lebert, Christine; Meert, Anne-Pascale; Benoit, Dominique; Pene, Frédéric
2016-01-01
Invasive fungal infections (IFIs) are life-threatening complications of hematological malignancies that must be diagnosed early to allow effective treatment. Few data are available on the performance of serum (1–3)-β-D-glucan (BG) assays for diagnosing IFI in patients with hematological malignancies admitted to the intensive care unit (ICU). In this study, 737 consecutive patients with hematological malignancies admitted to 17 ICUs routinely underwent a BG assay at ICU admission. IFIs were diagnosed using standard criteria applied by three independent specialists. Among the 737 patients, 439 (60%) required mechanical ventilation and 273 (37%) died before hospital discharge. Factors known to alter BG concentrations were identified in most patients. IFIs were documented in 78 (10.6%) patients (invasive pulmonary aspergillosis, n = 54; Pneumocystis jirovecii pneumonia, n = 13; candidemia, n = 13; and fusarium infections, n = 3). BG concentrations (pg/mL) were higher in patients with than without IFI (144 (77–510) vs. 50 (30–125), < 0.0001). With 80 pg/mL as the cutoff, sensitivity was 72%, specificity 65%, and area-under-the-curve 0.74 (0.68–0.79). Assuming a prevalence of 10%, the negative and positive predictive values were 94% and 21%. By multivariable analysis, factors independently associated with BG > 80 pg/mL were IFI, admission SOFA score, autologous bone-marrow or hematopoietic stem-cell transplantation, and microbiologically documented bacterial infection. In conclusion, in unselected critically ill hematology patients with factors known to affect serum BG, this biomarker showed only moderate diagnostic performance and rarely detected IFI. However, the negative predictive value was high. Studies are needed to assess whether a negative BG test indicates that antifungal de-escalation is safe. PMID:26910891
Predictors of false negative sentinel lymph node biopsy in trunk and extremity melanoma.
Sinnamon, Andrew J; Neuwirth, Madalyn G; Bartlett, Edmund K; Zaheer, Salman; Etherington, Mark S; Xu, Xiaowei; Elder, David E; Czerniecki, Brian J; Fraker, Douglas L; Karakousis, Giorgos C
2017-12-01
Nodal recurrence following negative sentinel lymph node biopsy (SLNB) for melanoma is known as false-negative (FN) SLNB. Risk factors for FN SLNB among patients with trunk and extremity melanoma have not been well-defined. After retrospective review, SLNB procedures were classified FN, true positive (TP; positive SLNB), or true negative (TN; negative SLNB without recurrence). Factors associated with high false negative rate (FNR) and low negative predictive value (NPV) were identified by comparing FNs to TPs and TNs, respectively. Survival was evaluated using Kaplan-Meier methods. Of 1728 patients, 234 were TP and 37 were FN for overall FNR of 14% and NPV of 97.5%. Age ≥65 years was independently associated with high FNR (FNR 20% in this group). Breslow thickness >1 mm and ulceration were independently associated with low NPV. Among patients with ulcerated tumors >4 mm, NPV was 88%. Median time to recurrence for FNs was 13 months. Among patients with primary melanomas ≤2 mm in depth, overall and distant disease-free survival were significantly shorter with FN SLNB than TP SLNB. Older age is associated with increased FNR; patients with thick, ulcerated lesions should be considered for increased nodal surveillance after negative SLNB given low NPV in this group. © 2017 Wiley Periodicals, Inc.
The role of perceived parenting in familial aggregation of anxiety disorders in children.
van Gastel, W; Legerstee, J S; Ferdinand, R F
2009-01-01
This study was designed to explore the role of perceived parenting style in the familial aggregation of anxiety disorders. We examined the association between parental and child anxiety diagnoses, and tested whether this association was partly due to a perceived parenting style. The study was conducted in a clinical sample as well as in a control sample. Parental lifetime and current anxiety diagnoses were significantly associated with child anxiety diagnoses. When maternal and paternal lifetime and current anxiety diagnoses were entered as separate predictors, only maternal current anxiety diagnoses appeared to be significant. Perceived parenting style was assessed with the dimensions "overprotection," "emotional warmth," "rejection," and "anxious rearing." Results indicated that only maternal and paternal 'overprotection' was significantly but negatively associated with child anxiety. However, further analyses showed that 'overprotection' did not have a significant mediating role in the familial aggregation of anxiety disorders.
Bondi, Mark W.; Edmonds, Emily C.; Jak, Amy J.; Clark, Lindsay R.; Delano-Wood, Lisa; McDonald, Carrie R.; Nation, Daniel A.; Libon, David J.; Au, Rhoda; Galasko, Douglas; Salmon, David P.
2014-01-01
We compared two methods of diagnosing mild cognitive impairment (MCI): conventional Petersen/Winblad criteria as operationalized by the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and an actuarial neuropsychological method put forward by Jak and Bondi designed to balance sensitivity and reliability. 1,150 ADNI participants were diagnosed at baseline as cognitively normal (CN) or MCI via ADNI criteria (MCI: n = 846; CN: n = 304) or Jak/Bondi criteria (MCI: n = 401; CN: n = 749), and the two MCI samples were submitted to cluster and discriminant function analyses. Resulting cluster groups were then compared and further examined for APOE allelic frequencies, cerebrospinal fluid (CSF) Alzheimer’s disease (AD) biomarker levels, and clinical outcomes. Results revealed that both criteria produced a mildly impaired Amnestic subtype and a more severely impaired Dysexecutive/Mixed subtype. The neuropsychological Jak/Bondi criteria uniquely yielded a third Impaired Language subtype, whereas conventional Petersen/Winblad ADNI criteria produced a third subtype comprising nearly one-third of the sample that performed within normal limits across the cognitive measures, suggesting this method’s susceptibility to false positive diagnoses. MCI participants diagnosed via neuropsychological criteria yielded dissociable cognitive phenotypes, significant CSF AD biomarker associations, more stable diagnoses, and identified greater percentages of participants who progressed to dementia than conventional MCI diagnostic criteria. Importantly, the actuarial neuropsychological method did not produce a subtype that performed within normal limits on the cognitive testing, unlike the conventional diagnostic method. Findings support the need for refinement of MCI diagnoses to incorporate more comprehensive neuropsychological methods, with resulting gains in empirical characterization of specific cognitive phenotypes, biomarker associations, stability of diagnoses, and prediction of progression. Refinement of MCI diagnostic methods may also yield gains in biomarker and clinical trial study findings because of improvements in sample compositions of ‘true positive’ cases and removal of ‘false positive’ cases. PMID:24844687
Central retinal artery occlusion in an ANCA negative Churg-Strauss syndrome patient.
Türkçüoğlu, Peykan; Isik, Ahmet; Deniz, Nurettin; Turgut, Burak; Kan, Elif Kiliç
2007-12-01
To describe a central retinal artery occlusion in a patient with antineutrophil cytoplasmic antibody (ANCA) negative Churg-Strauss syndrome. Review of clinical and laboratory findings of a 44-year-old woman with ANCA negative Churg-Strauss syndrome that developed sudden vision loss in left eye. Left central retinal artery occlusion was diagnosed by retinal whitening, a cherry-red spot, and delayed arterial filling on fluorescein angiography. Perinuclear ANCA and cytoplasmic ANCA were negative. Central retinal artery occlusion can occur in ANCA negative Churg-Strauss syndrome. Patients with this diagnosis should be considered for prophylactic high dose corticosteroid, regardless of their ANCA status.
Gökbuget, Nicola; Dombret, Hervè; Ribera, Jose-Maria; Fielding, Adele K.; Advani, Anjali; Bassan, Renato; Chia, Victoria; Doubek, Michael; Giebel, Sebastian; Hoelzer, Dieter; Ifrah, Norbert; Katz, Aaron; Kelsh, Michael; Martinelli, Giovanni; Morgades, Mireia; O’Brien, Susan; Rowe, Jacob M.; Stieglmaier, Julia; Wadleigh, Martha; Kantarjian, Hagop
2016-01-01
Adults with relapsed/refractory acute lymphoblastic leukemia have an unfavourable prognosis, which is influenced by disease and patient characteristics. To further evaluate these characteristics, a retrospective analysis of 1,706 adult patients with Ph-negative relapsed/refractory B-precursor acute lymphoblastic leukemia diagnosed between 1990–2013 was conducted using data reflecting the standard of care from 11 study groups and large centers in Europe and the United States. Outcomes included complete remission, overall survival, and realization of stem cell transplantation after salvage treatment. The overall complete remission rate after first salvage was 40%, ranging from 35%–41% across disease status categories (primary refractory, relapsed with or without prior transplant), and was lower after second (21%) and third or greater (11%) salvage. The overall complete remission rate was higher for patients diagnosed from 2005 onward (45%, 95% CI: 39%–50%). One- and three-year survival rates after first, second, and third or greater salvage were 26% and 11%, 18% and 6%, and 15% and 4%, respectively, and rates were 2%–5% higher among patients diagnosed from 2005. Prognostic factors included younger age, longer duration of first remission, and lower white blood cell counts at primary diagnosis. This large dataset can provide detailed reference outcomes for patients with relapsed/refractory Ph-negative B-precursor acute lymphoblastic leukemia. clinicaltrials.gov identifier: 02003612 PMID:27587380
Zhou, D C; Zittoun, R; Marie, J P
1995-10-01
The frequency, prognostic value and interrelation of MRP and MDR1 gene expressions were investigated by quantitative reverse transcription polymerase chain reaction (RT-PCR) in 91 cases of de novo acute myeloid leukemia (AML), of which 51 were newly diagnosed, 21 were relapsed, and 19 were refractory patients. As compared with normal bone marrow cells and peripheral granulocytes, an overexpression of MRP gene was found in 24% (22 of 91) cases of de novo AML. The incidence of MRP gene overexpression tended to be higher in relapsed patients than in newly diagnosed patients (38 vs 18%, P = 0.063). In 52 evaluable newly diagnosed and relapsed patients treated with MDR-related drugs, both MRP and MDR1 gene overexpressions correlated to a higher rate of emergence of clinical drug resistance (83 vs 22%, P = 0.005; and 67 vs 24%, P = 0.045, respectively). A positive correlation was found between MRP and MDR1 gene overexpressions (R = 0.53, P < 0.001). Analysis of 46 evaluable MDR1-negative cases revealed a trend for higher resistant disease rate in MRP-positive patients as compared with MRP-negative patients (100 vs 20%, P = 0.053). These data suggest that MRP, like MDR1, may have an important negative impact on the outcome of chemotherapy, and that there may be a common mechanism of induction for the overexpression of these two genes.
Hansel, D E; DeMarzo, A M; Platz, E A; Jadallah, S; Hicks, J; Epstein, J I; Partin, A W; Netto, G J
2007-05-01
Early prostate cancer antigen is a nuclear matrix protein that was recently shown to be expressed in prostate adenocarcinoma and adjacent benign tissue. Previous studies have demonstrated early prostate cancer antigen expression in benign prostate tissue up to 5 years before a diagnosis of prostate carcinoma, suggesting that early prostate cancer antigen could be used as a potential predictive marker. We evaluated early prostate cancer antigen expression by immunohistochemistry using a polyclonal antibody (Onconome Inc., Seattle, Washington) on benign biopsies from 98 patients. Biopsies were obtained from 4 groups that included 39 patients with first time negative biopsy (group 1), 24 patients with persistently negative biopsies (group 2), 8 patients with initially negative biopsies who were subsequently diagnosed with prostate carcinoma (group 3) and negative biopsies obtained from 27 cases where other concurrent biopsies contained prostate carcinoma (group 4). Early prostate cancer antigen staining was assessed by 2 of the authors who were blind to the group of the examined sections. Staining intensity (range 0 to 3) and extent (range 1 to 3) scores were assigned. The presence of intensity 3 staining in any of the blocks of a biopsy specimen was considered as positive for early prostate cancer antigen for the primary outcome in the statistical analysis. In addition, as secondary outcomes we evaluated the data using the proportion of blocks with intensity 3 early prostate cancer antigen staining, the mean of the product of staining intensity and staining extent of all blocks within a biopsy, and the mean of the product of intensity 3 staining and extent. Primary outcome analysis revealed the proportion of early prostate cancer antigen positivity to be highest in group 3 (6 of 8, 75%) and lowest in group 2 (7 of 24, 29%, p=0.04 for differences among groups). A relatively higher than expected proportion of early prostate cancer antigen positivity was present in group 1 (23 of 39, 59%). Early prostate cancer antigen was negative in 41% of group 4 who were known to harbor prostate carcinoma. The proportion of early prostate cancer antigen positivity was statistically significantly lower in group 2 than in each of the other groups when compared pairwise. A lower proportion of early prostate cancer antigen positivity was encountered in older archival tissue blocks (p<0.0001) pointing to a potential confounding factor. Corrected for block age, group 3 was the only group to remain statistically significantly different in early prostate cancer antigen positivity compared to the reference group 2. Similar findings were obtained when adjustments for patient age were made and when analysis was based on secondary outcome measurements. Our study showed a higher proportion of early prostate cancer antigen expression in initial negative prostate biopsy of patients who were diagnosed with prostate carcinoma on subsequent followup biopsies. We found a relatively high proportion of early prostate cancer antigen positivity (59%) in the group with first time negative biopsies and a potential 41% rate of false-negative early prostate cancer antigen staining in benign biopsies from cases with documented prostate carcinoma on concurrent cores. The lower early prostate cancer antigen positivity in cases with older blocks raises the question of a confounding effect of block age. Additional studies on the antigenic properties of early prostate cancer antigen in archival material are required to further delineate the usefulness of early prostate cancer antigen immunostaining on biopsy material.
False-negative syphilis treponemal enzyme immunoassay results in an HIV-infected case-patient.
Katz, Alan R; Komeya, Alan Y; Tomas, Juval E
2017-06-01
We present a case report of a false-negative syphilis treponemal enzyme immunoassay test result in an HIV-infected male. While treponemal tests are widely considered to be more sensitive and specific than non-treponemal tests, our findings point to potential challenges using the reverse sequence syphilis screening algorithm.
Ferreira, Bruno G.; Falcioni, Renan; Guedes, Lubia M.; Avritzer, Sofia C.; Antunes, Werner C.; Souza, Luiz A.; Isaias, Rosy M.S.
2016-01-01
Polyethylene glycol (PEG) is a low-cost and advantageous embedding medium, which maintains the majority of cell contents unaltered during the embedding process. Some hard or complex plant materials are better embedded in PEG than in other usual embedding media. However, the histochemical tests for phenolics and lignins in PEG-embedded plant tissues commonly result in false negatives. We hypothesize that these false negatives should be prevented by the use of distinct fixatives, which should avoid the bonds between PEG and phenols. Novel protocols for phenolics and flavanols detection are efficiently tested, with fixation of the samples in ferrous sulfate and formalin or in caffeine and sodium benzoate, respectively. The differentiation of lignin types is possible in safranin-stained sections observed under fluorescence. The Maule’s test faultlessly distinguishes syringyl-rich from guaiacyl- and hydroxyphenyl-rich lignins in PEG-embedded material under light microscopy. Current hypothesis is corroborated, that is, the adequate fixation solves the false-negative results, and the new proposed protocols fill up some gaps on the detection of phenolics and lignins. PMID:28117630
Optimal Hemoglobin A1c Levels for Screening of Diabetes and Prediabetes in the Japanese Population.
Shimodaira, Masanori; Okaniwa, Shinji; Hanyu, Norinao; Nakayama, Tomohiro
2015-01-01
The aim of this study was to evaluate the utility of hemoglobin A1c (HbA1c) to identify individuals with diabetes and prediabetes in the Japanese population. A total of 1372 individuals without known diabetes were selected for this study. A 75 g oral glucose tolerance test (OGTT) was used to diagnose diabetes and prediabetes. The ability of HbA1c to detect diabetes and prediabetes was investigated using receiver operating characteristic (ROC) analysis. The kappa (κ) coefficient was used to test the agreement between HbA1c categorization and OGTT-based diagnosis. ROC analysis demonstrated that HbA1c was a good test to identify diabetes and prediabetes, with areas under the curve of 0.918 and 0.714, respectively. Optimal HbA1c cutoffs for diagnosing diabetes and prediabetes were 6.0% (sensitivity 83.7%, specificity 87.6%) and 5.7% (sensitivity 60.6%, specificity 72.1%), respectively, although the cutoff for prediabetes showed low accuracy (67.6%) and a high false-negative rate (39.4%). Agreement between HbA1c categorization and OGTT-based diagnosis was low in diabetes (κ = 0.399) and prediabetes (κ = 0.324). In Japanese subjects, the HbA1c cutoff of 6.0% had appropriate sensitivity and specificity for diabetes screening, whereas the cutoff of 5.7% had modest sensitivity and specificity in identifying prediabetes. Thus, HbA1c may be inadequate as a screening tool for prediabetes.
Initial Experience with a Wireless Ultrasound-Guided Vacuum-Assisted Breast Biopsy Device
Choi, E-Ryung; Han, Boo-Kyung; Ko, Eun Sook; Ko, Eun Young; Choi, Ji Soo; Cho, Eun Yoon; Nam, Seok Jin
2015-01-01
Objective To determine the imaging characteristic of frequent target lesions of wireless ultrasound (US)-guided, vacuum-assisted breast biopsy (Wi-UVAB) and to evaluate diagnostic yield, accuracy and complication of the device in indeterminate breast lesions. Materials and Methods From March 2013 to October 2014, 114 women (age range, 29–76 years; mean age, 50.0 years) underwent Wi-UVAB using a 13-gauge needle (Mammotome Elite®; Devicor Medical Products, Cincinnati, OH, USA). In 103 lesions of 96 women with surgical (n = 81) or follow-up (n = 22) data, complications, biopsy procedure, imaging findings of biopsy targets and histologic results were reviewed. Results Mean number of biopsy cores was 10 (range 4–25). Nine patients developed moderate bleeding. All lesions were suspicious on US, and included non-mass lesions (67.0%) and mass lesions (33.0%). Visible calcifications on US were evident in 57.3% of the target lesions. Most of the lesions (93.2%) were nonpalpable. Sixty-six (64.1%) were malignant [ductal carcinoma in situ (DCIS) rate, 61%] and 12 were high-risk lesions (11.7%). Histologic underestimation was identified in 11 of 40 (27.5%). DCIS cases and in 3 of 9 (33.3%) high-risk lesions necessitating surgery. There was no false-negative case. Conclusion Wi-UVAB is very handy and advantageous for US-unapparent non-mass lesions to diagnose DCIS, especially for calcification cases. Histologic underestimation is unavoidable; still, Wi-UVAB is safe and accurate to diagnose a malignancy. PMID:26630136
The effect of silicone implants on the diagnosis, prognosis, and treatment of breast cancer.
Handel, Neal
2007-12-01
Because of the prevalence of breast cancer, many augmented women eventually will develop the disease. This article reviews what is known about the effect of implants on the detection, prognosis, and treatment of carcinoma of the breast. Observations were made on 4082 breast cancer patients (3953 nonaugmented and 129 augmented) treated over a 23-year time span. Findings in the two groups were compared and differences analyzed statistically. Mammograms of all women with palpable lesions were reviewed to assess mammographic sensitivity in patients with and without implants. Cosmetic outcomes in augmented patients treated with breast conservation therapy were reviewed. Augmented patients presented more frequently with palpable lesions, invasive tumors, axillary nodal metastases, and false-negative mammograms. However, there was no significant difference in stage of disease, tumor size, recurrence rates, or survival between the two groups. Augmented patients treated with breast conservation therapy often experienced poor cosmetic results and frequently required reoperation. Despite the diminished sensitivity of mammography in women with implants, augmented and nonaugmented patients are diagnosed at a similar stage of disease and have a comparable prognosis. Implants may impair mammography but appear to facilitate tumor detection on physical examination. Magnetic resonance imaging and breast ultrasound may be useful adjuncts, but conventional mammography remains the most reliable tool for diagnosing early breast cancer in augmented patients. Breast implants do not interfere with mastectomy or breast reconstruction but may compromise the outcome of breast conservation therapy.
[Validation of BREV: comparison with reference battery in 173 children with learning disorders].
Billard, C; Ducot, B; Pinton, F; Coste-Zeitoun, D; Picard, S; Warszawski, J
2006-01-01
The BREV battery (Battery for rapid evaluation of cognitive functions) is a tool which can be used for the rapid neuropsychological evaluation of children aged between 4 and 9 years. After standardization (700 unaffected children) and validation by comparison with a reference battery (202 children with epilepsy), the aim of this study was further validation in 173 children with learning disorders. The study protocol included administration of the BREV, precise neuropsychological examination and evaluation of oral and written language. Statistical analysis was used to compare the findings of the BREV with those of the reference method, and the recommendations indicated by the BREV with the final diagnoses, and to define the sensitivity and the specificity of the BREV battery. All the correlations between BREV tests and reference tests were significant. Recommendations after the BREV were in agreement with the conclusions of the reference evaluation in 168/172 children for language, 145/173 for the psychometric evaluation. For only 4 chidren, the results of the BREV were false negative. Diagnoses corresponded in 168/173 children for oral language, in 102/110 for written language, 166/173 for praxis disorders and 157/173 for intellectual deficit. The most predictive subtests of the BREV and sensitivity and specificity of verbal and non-verbal scores were calculated. The BREV is a reliable examination, in learning disorders, to determine the most complementary investigations both in terms of language disorders and for non-verbal or global learning disabilities.
Mehler, W Tyler; Keough, Michael J; Pettigrove, Vincent
2018-04-01
Three common false-negative scenarios have been encountered with amendment addition in whole-sediment toxicity identification evaluations (TIEs): dilution of toxicity by amendment addition (i.e., not toxic enough), not enough amendment present to reduce toxicity (i.e., too toxic), and the amendment itself elicits a toxic response (i.e., secondary amendment effect). One such amendment in which all 3 types of false-negatives have been observed is with the nonpolar organic amendment (activated carbon or powdered coconut charcoal). The objective of the present study was to reduce the likelihood of encountering false-negatives with this amendment and to increase the value of the whole-sediment TIE bioassay. To do this, the present study evaluated the effects of various activated carbon additions to survival, growth, emergence, and mean development rate of Chironomus tepperi. Using this information, an alternative method for this amendment was developed which utilized a combination of multiple amendment addition ratios based on wet weight (1%, lower likelihood of the secondary amendment effect; 5%, higher reduction of contaminant) and nonconventional endpoints (emergence, mean development rate). This alternative method was then validated in the laboratory (using spiked sediments) and with contaminated field sediments. Using these multiple activated carbon ratios in combination with additional endpoints (namely, emergence) reduced the likelihood of all 3 types of false-negatives and provided a more sensitive evaluation of risk. Environ Toxicol Chem 2018;37:1219-1230. © 2017 SETAC. © 2017 SETAC.
Nelson, David B; McIntire, Donald D; Leveno, Kenneth J
2017-07-01
To evaluate perinatal outcomes in women sent home with a diagnosis of false labor at term and assess the time interval to return for delivery. This was a prospective observational cohort study of women at 37 0/7 to 41 6/7 weeks of gestation without pre-existing medical complications who presented to our hospital-based triage unit with symptoms of labor and underwent a standardized evaluation. Women diagnosed as having false labor with a live singleton fetus in cephalic presentation without a prior cesarean delivery and sent home were compared with a group of similar women diagnosed to be in spontaneous labor. Women with hypertension, diabetes, and known fetal malformations were excluded. Using a perinatal composite outcome of respiratory insufficiency, intraventricular hemorrhage, culture-proven sepsis, Apgar score 3 or less at 5 minutes, phototherapy, and perinatal death, we tested the noninferiority of being sent home compared with being admitted for labor. The relationship of cervical dilatation to the time interval from discharge home to delivery was also analyzed. Between October 2012 and March 2016, a total of 3,949 women met inclusion criteria and were diagnosed with false labor, discharged, and returned to deliver, whereas 2,592 similar women were admitted in early labor. The mean interval from discharge to return was 4.9 days. Cesarean delivery rates were not different between the study groups-11% for both (P=.69), and the perinatal composite outcome rates were not significantly different between those sent home and those admitted-3.2% compared with 3.1% (P=.79). Women with more advanced cervical dilatation at discharge returned and delivered significantly earlier than those with less dilatation regardless of parity. Discharge with false labor at term after a standardized assessment in a triage unit was not associated with increased rates of adverse perinatal composite outcomes or cesarean delivery. The time interval to return for delivery was significantly associated with the cervical dilatation at discharge.
Wahlund, Katarina; Sorman, Karolina; Gavazzeni, Joachim; Fischer, Håkan; Kristiansson, Marianne
2010-11-30
Altered autonomic arousal in relation to offending behavior has mainly been investigated in subjects with varying degrees of psychopathic traits. The present study sets out to investigate subjective ratings and skin conductance responses (SCRs) in mentally disordered offenders with various diagnoses but without psychopathy, specifically recruited from the forensic psychiatric system. Two subgroups were investigated; an antisocial group with antisocial personality disorder (APD) or antisocial traits (n=16) and a non-antisocial group with various diagnoses (n=25), in relation to a healthy non-criminal control group (n=20). All participants were male. SCRs and subjective ratings of arousal and valence were measured for neutral and negative pictures from the International Affective Picture System (IAPS). The offenders showed significantly lower SCRs and subjective ratings than the control group. Moreover, there was no significant difference between antisocial and non-antisocial offenders, indicating that antisocial behavior might not be a differential factor. Thus, attenuated emotional responses may be a characteristic shared by mentally disordered offenders overall. Copyright © 2009 Elsevier Ltd. All rights reserved.
Pereira, Graziella Hanna; Lanzoni, Valéria Pereira Barbosa; Beirão, Elisa Maria; Timerman, Artur; Melhem, Marcia de Souza Carvalho
2015-12-01
Paracoccidioidomycosis and histoplasmosis are systemic fungal infections endemic in Brazil. Disseminated clinical forms are uncommon in immunocompetent individuals. We describe two HIV-negative patients with disseminated fungal infections, paracoccidioidomycosis and histoplasmosis, who were diagnosed by biopsies of suprarenal lesions. Both were treated for a prolonged period with oral antifungal agents, and both showed favorable outcomes.
PEREIRA, Graziella Hanna; LANZONI, Valéria Pereira Barbosa; BEIRÃO, Elisa Maria; TIMERMAN, Artur; MELHEM, Marcia de Souza Carvalho
2015-01-01
Paracoccidioidomycosis and histoplasmosis are systemic fungal infections endemic in Brazil. Disseminated clinical forms are uncommon in immunocompetent individuals. We describe two HIV-negative patients with disseminated fungal infections, paracoccidioidomycosis and histoplasmosis, who were diagnosed by biopsies of suprarenal lesions. Both were treated for a prolonged period with oral antifungal agents, and both showed favorable outcomes. PMID:27049710
ERIC Educational Resources Information Center
Christiansen, Hanna; Oades, Robert D.
2010-01-01
Objective: Negative priming (NP) is the slowed response to a stimulus that was previously ignored. Response times in NP task conditions were compared with the interference provided by congruent/incongruent stimuli in a Stroop condition in the same task in children diagnosed with attention-deficit hyperactivity disorder (ADHD), their unaffected…
Risk management and precaution: insights on the cautious use of evidence.
Hrudey, Steve E; Leiss, William
2003-01-01
Risk management, done well, should be inherently precautionary. Adopting an appropriate degree of precaution with respect to feared health and environmental hazards is fundamental to risk management. The real problem is in deciding how precautionary to be in the face of inevitable uncertainties, demanding that we understand the equally inevitable false positives and false negatives from screening evidence. We consider a framework for detection and judgment of evidence of well-characterized hazards, using the concepts of sensitivity, specificity, positive predictive value, and negative predictive value that are well established for medical diagnosis. Our confidence in predicting the likelihood of a true danger inevitably will be poor for rare hazards because of the predominance of false positives; failing to detect a true danger is less likely because false negatives must be rarer than the danger itself. Because most controversial environmental hazards arise infrequently, this truth poses a dilemma for risk management. PMID:14527835
Experienced consequences of being diagnosed with ADHD as an adult - a qualitative study.
Hansson Halleröd, Sara Lina; Anckarsäter, Henrik; Råstam, Maria; Hansson Scherman, Marianne
2015-02-26
Despite increasing knowledge of attention deficit hyperactivity disorder (ADHD) across the life span, there is still little research on adults' own experiences of being diagnosed with ADHD. The aim of the present study was to explore and describe patients' experiences and perceptions of being diagnosed with ADHD in adulthood. The study can be seen as an attempt to validate the diagnosis from a patient perspective. Twenty-one adults diagnosed with ADHD were individually interviewed. The interviews were open-ended and exploratory, analysed with a qualitative phenomenographical approach, and the results were described in categories. Positive experiences were dominant, but there was a complex intra- and inter-individual variation of experiences. Descriptions focused on the diagnosis, on identity, and on life. The diagnosis was described as explaining a previously inexplicable life history, but was also questioned, both as a phenomenon and in relation to the individual (the diagnosis in focus). It was experienced as providing self-knowledge and increased value, but could also cause devaluation and concern about identity (identity in focus). It meant help to achieve a better life, but was also perceived to restrict possibilities and cause disappointment over lack of professional help. It could lead to a wish for an earlier diagnosis that could have spared suffering, as well as to a changed view of the participants' relatives (life in focus). All but one of the interviewees expressed important positive consequences of being diagnosed with ADHD. About half of them acknowledged negative aspects of being diagnosed, but none regretted going through the neuropsychiatric evaluation. From a patient perspective, there are major positive consequences of being diagnosed with ADHD, compared to the undiagnosed situation. Knowledge of the individual's combination of experiences is important for professionals, as these experiences can affect well-being and interfere with treatment. Negative experiences in particular might need to be addressed in the treatment work.
Automatic stereotyping against people with schizophrenia, schizoaffective and affective disorders
Rüsch, Nicolas; Corrigan, Patrick W.; Todd, Andrew R.; Bodenhausen, Galen V.
2010-01-01
Similar to members of the public, people with mental illness may exhibit general negative automatic prejudice against their own group. However, it is unclear whether more specific negative stereotypes are automatically activated among diagnosed individuals and how such automatic stereotyping may be related to self-reported attitudes and emotional reactions. We therefore studied automatically activated reactions toward mental illness among 85 people with schizophrenia, schizoaffective or affective disorders as well as among 50 members of the general public, using a Lexical Decision Task to measure automatic stereotyping. Deliberately endorsed attitudes and emotional reactions were assessed by self-report. Independent of diagnosis, people with mental illness showed less negative automatic stereotyping than did members of the public. Among members of the public, stronger automatic stereotyping was associated with more self-reported shame about a potential mental illness and more anger toward stigmatized individuals. Reduced automatic stereotyping in the diagnosed group suggests that people with mental illness might not entirely internalize societal stigma. Among members of the public, automatic stereotyping predicted negative emotional reactions to people with mental illness. Initiatives to reduce the impact of public stigma and internalized stigma should take automatic stereotyping and related emotional aspects of stigma into account. PMID:20843560
Johnson, Susan L; Tabaei, Bahman P; Herman, William H
2005-02-01
To simulate the outcomes of alternative strategies for screening the U.S. population 45-74 years of age for type 2 diabetes. We simulated screening with random plasma glucose (RPG) and cut points of 100, 130, and 160 mg/dl and a multivariate equation including RPG and other variables. Over 15 years, we simulated screening at intervals of 1, 3, and 5 years. All positive screening tests were followed by a diagnostic fasting plasma glucose or an oral glucose tolerance test. Outcomes include the numbers of false-negative, true-positive, and false-positive screening tests and the direct and indirect costs. At year 15, screening every 3 years with an RPG cut point of 100 mg/dl left 0.2 million false negatives, an RPG of 130 mg/dl or the equation left 1.3 million false negatives, and an RPG of 160 mg/dl left 2.8 million false negatives. Over 15 years, the absolute difference between the most sensitive and most specific screening strategy was 4.5 million true positives and 476 million false-positives. Strategies using RPG cut points of 130 mg/dl or the multivariate equation every 3 years identified 17.3 million true positives; however, the equation identified fewer false-positives. The total cost of the most sensitive screening strategy was $42.7 billion and that of the most specific strategy was $6.9 billion. Screening for type 2 diabetes every 3 years with an RPG cut point of 130 mg/dl or the multivariate equation provides good yield and minimizes false-positive screening tests and costs.
Sievert, Lynnette L; Reza, Angela; Mills, Phoebe; Morrison, Lynn; Rahberg, Nichole; Goodloe, Amber; Sutherland, Michael; Brown, Daniel E
2010-01-01
The aims of this study were to test for a diurnal pattern in hot flashes in a multiethnic population living in a hot, humid environment and to examine the rates of concordance between objective and subjective measures of hot flashes using ambulatory and laboratory measures. Study participants aged 45 to 55 years were recruited from the general population of Hilo, HI. Women wore a Biolog hot flash monitor (UFI, Morro Bay, CA), kept a diary for 24 hours, and also participated in 3-hour laboratory measures (n = 199). Diurnal patterns were assessed using polynomial regression. For each woman, objectively recorded hot flashes that matched subjective experience were treated as true-positive readings. Subjective hot flashes were considered the standard for computing false-positive and false-negative readings. True-positive, false-positive, and false-negative readings were compared across ethnic groups by chi analyses. Frequencies of sternal, nuchal, and subjective hot flashes peaked at 1500 +/- 1 hours with no difference by ethnicity. Laboratory results supported the pattern seen in ambulatory monitoring. Sternal and nuchal monitoring showed the same frequency of true-positive measures, but nonsternal electrodes picked up more false-positive readings. Laboratory monitoring showed very low frequencies of false negatives. There were no ethnic differences in the frequency of true-positive or false-positive measures. Women of European descent were more likely to report hot flashes that were not objectively demonstrated (false-negative measures). The diurnal pattern and peak in hot flash occurrence in the hot humid environment of Hilo were similar to results from more temperate environments. Lack of variation in sternal versus nonsternal measures and in true-positive measures across ethnicities suggests no appreciable effect of population variation in sweating patterns.
Sievert, Lynnette L.; Reza, Angela; Mills, Phoebe; Morrison, Lynn; Rahberg, Nichole; Goodloe, Amber; Sutherland, Michael; Brown, Daniel E.
2010-01-01
Objective To test for a diurnal pattern in hot flashes in a multi-ethnic population living in a hot, humid environment. To examine rates of concordance between objective and subjective measures of hot flashes using ambulatory and laboratory measures. Methods Study participants aged 45–55 were recruited from the general population of Hilo, Hawaii. Women wore a Biolog hot flash monitor, kept a diary for 24-hours, and also participated in 3-hour laboratory measures (n=199). Diurnal patterns were assessed using polynomial regression. For each woman, objectively recorded hot flashes that matched subjective experience were treated as true positive readings. Subjective hot flashes were considered the standard for computing false positive and false negative readings. True positive, false positive, and false negative readings were compared across ethnic groups by chi-square analyses. Results Frequencies of sternal, nuchal and subjective hot flashes peaked at 15:00 ± 1 hour with no difference by ethnicity. Laboratory results supported the pattern seen in ambulatory monitoring. Sternal and nuchal monitoring showed the same frequency of true positive measures, but non-sternal electrodes picked up more false positive readings. Laboratory monitoring showed very low frequencies of false negatives. There were no ethnic differences in the frequency of true positive or false positive measures. Women of European descent were more likely to report hot flashes that were not objectively demonstrated (false negative measures). Conclusions The diurnal pattern and peak in hot flash occurrence in the hot humid environment of Hilo was similar to results from more temperate environments. Lack of variation in sternal vs. non-sternal measures, and in true positive measures across ethnicities suggests no appreciable effect of population variation in sweating patterns. PMID:20220538
Park, So Yoon; Choi, Ji Soo; Han, Boo-Kyung; Ko, Eun Young; Ko, Eun Sook
2017-09-01
To investigate factors related to false shear wave elastography (SWE) results for breast non-mass lesions (NMLs) detected by B-mode US. This retrospective study enrolled 152 NMLs detected by B-mode US and later pathologically confirmed (79 malignant, 73 benign). All lesions underwent B-mode US and SWE. Quantitative (mean elasticity [E mean ]) and qualitative (maximum stiffness colour) SWE parameters were assessed, and 'E mean > 85.1 kPa' or 'stiff colour (green to red)' determined malignancy. Final SWE results were matched to pathology results. Multivariate logistic regression analysis identified factors associated with false SWE results for diagnosis of breast NMLs. Associated calcifications (E mean : odds ratio [OR] = 7.60, P < 0.01; maximum stiffness colour: OR = 6.30, P = 0.02), in situ cancer compared to invasive cancer (maximum stiffness colour: OR = 5.29, P = 0.02), and lesion size (E mean : OR = 0.90, P < 0.01; maximum stiffness colour: OR = 0.91, P = 0.01) were significantly associated with false negative SWE results for malignant NMLs. Distance from the nipple (E mean : OR = 0.84, P = 0.03; maximum stiffness colour: OR = 0.93, P = 0.04) was significantly associated with false positive SWE results for benign NMLs. Presence of associated calcifications, absence of the invasive component, and smaller lesion size for malignant NMLs and shorter distance from the nipple for benign NMLs are factors significantly associated with false SWE results. • Calcification and size are associated with false negative SWE in malignant NMLs. • In situ cancer is associated with false negative SWE in malignant NMLs. • Distance from the nipple is associated with false positive SWE in benign NMLs. • These factors need consideration when performing SWE on breast NMLs.
Choi, Hae-Yoon; Kensinger, Elizabeth A; Rajaram, Suparna
2017-09-01
Social transmission of memory and its consequence on collective memory have generated enduring interdisciplinary interest because of their widespread significance in interpersonal, sociocultural, and political arenas. We tested the influence of 3 key factors-emotional salience of information, group structure, and information distribution-on mnemonic transmission, social contagion, and collective memory. Participants individually studied emotionally salient (negative or positive) and nonemotional (neutral) picture-word pairs that were completely shared, partially shared, or unshared within participant triads, and then completed 3 consecutive recalls in 1 of 3 conditions: individual-individual-individual (control), collaborative-collaborative (identical group; insular structure)-individual, and collaborative-collaborative (reconfigured group; diverse structure)-individual. Collaboration enhanced negative memories especially in insular group structure and especially for shared information, and promoted collective forgetting of positive memories. Diverse group structure reduced this negativity effect. Unequally distributed information led to social contagion that creates false memories; diverse structure propagated a greater variety of false memories whereas insular structure promoted confidence in false recognition and false collective memory. A simultaneous assessment of network structure, information distribution, and emotional valence breaks new ground to specify how network structure shapes the spread of negative memories and false memories, and the emergence of collective memory. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Misinformation, partial knowledge and guessing in true/false tests.
Burton, Richard F
2002-09-01
Examiners disagree on whether or not multiple choice and true/false tests should be negatively marked. Much of the debate has been clouded by neglect of the role of misinformation and by vagueness regarding both the specification of test types and "partial knowledge" in relation to guessing. Moreover, variations in risk-taking in the face of negative marking have too often been treated in absolute terms rather than in relation to the effect of guessing on test unreliability. This paper aims to clarify these points and to compare the ill-effects on test reliability of guessing and of variable risk-taking. Three published studies on medical students are examined. These compare responses in true/false tests obtained with both negative marking and number-right scoring. The studies yield data on misinformation and on the extent to which students may fail to benefit from distrusted partial knowledge when there is negative marking. A simple statistical model is used to compare variations in risk-taking with test unreliability due to blind guessing under number-right scoring conditions. Partial knowledge should be least problematic with independent true/false items. The effect on test reliability of blind guessing under number-right conditions is generally greater than that due to the over-cautiousness of some students when there is negative marking.
Parladé, Meaghan V.; Iverson, Jana M.
2015-01-01
This study evaluated the extent to which developmental change in coordination of social communication in early infancy differentiates children eventually diagnosed with ASD from those not likely to develop the disorder. A prospective longitudinal design was used to compare 9 infants at heightened risk for ASD (HR) later diagnosed with ASD, to 13 HR infants with language delay, 28 HR infants with no diagnosis, and 30 low risk infants. Hierarchical Linear Modeling (HLM) analyses revealed that ASD infants exhibited significantly slower growth in coordinations overall and in gestures coordinated with vocalizations, even relative to HR infants with language delay. Disruption in the development of gesture-vocalization coordinations may result in negative cascading effects that negatively impact later social and linguistic development. PMID:25689930
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dana Kelly; Kurt Vedros; Robert Youngblood
This paper examines false indication probabilities in the context of the Mitigating System Performance Index (MSPI), in order to investigate the pros and cons of different approaches to resolving two coupled issues: (1) sensitivity to the prior distribution used in calculating the Bayesian-corrected unreliability contribution to the MSPI, and (2) whether (in a particular plant configuration) to model the fuel oil transfer pump (FOTP) as a separate component, or integrally to its emergency diesel generator (EDG). False indication probabilities were calculated for the following situations: (1) all component reliability parameters at their baseline values, so that the true indication ismore » green, meaning that an indication of white or above would be false positive; (2) one or more components degraded to the extent that the true indication would be (mid) white, and “false” would be green (negative) or yellow (negative) or red (negative). In key respects, this was the approach taken in NUREG-1753. The prior distributions examined were the constrained noninformative (CNI) prior used currently by the MSPI, a mixture of conjugate priors, the Jeffreys noninformative prior, a nonconjugate log(istic)-normal prior, and the minimally informative prior investigated in (Kelly et al., 2010). The mid-white performance state was set at ?CDF = ?10 ? 10-6/yr. For each simulated time history, a check is made of whether the calculated ?CDF is above or below 10-6/yr. If the parameters were at their baseline values, and ?CDF > 10-6/yr, this is counted as a false positive. Conversely, if one or all of the parameters are set to values corresponding to ?CDF > 10-6/yr but that time history’s ?CDF < 10-6/yr, this is counted as a false negative indication. The false indication (positive or negative) probability is then estimated as the number of false positive or negative counts divided by the number of time histories (100,000). Results are presented for a set of base case parameter values, and three sensitivity cases in which the number of FOTP demands was reduced, along with the Birnbaum importance of the FOTP.« less
Familial Hypercholesterolaemia in the Era of Genetic Testing.
Hughes, D P; Viljoen, A; Wierzbicki, A S
2016-05-01
Familial hypercholesterolaemia (FH) is a relatively common autosomal dominant genetic condition leading to premature ischaemic vascular disease and mortality if left untreated. Currently, a universal consensus on the diagnostic criteria of FH does not exist but the diagnosis of FH largely relies on the evaluation of low density lipoprotein-cholesterol (LDL-C) levels, a careful documentation of family history, and the identification of clinical features. Diagnosis based purely on lipid levels remains common but there are several limitations to this method of diagnosis both practically and in the proportion of false-negatives and false-positives detected, resulting in substantial under-diagnosis of FH. In some countries, diagnostic algorithms are supplemented with genetic testing of the index case as well as genetic and lipid testing of relatives of the index case. Such "cascade" screening of families following identification of index cases appears to not only improve the rate of diagnosis but is also cost-effective. Currently, we observe a great variation in the excess mortality among patients with FH, which likely reflects a combination of additional genetic and environmental effects on risk overlaid on the risk associated with FH. Current accepted drug therapies for FH include statins and PSCK9 inhibitors. Further work is required to evaluate the cardiovascular disease risk in patients with genetically diagnosed FH and to determine whether a risk-based approach to the treatment of FH is appropriate.
Chusri, Sarunyou; Hortiwakul, Thanaporn; Sathaporn, Natthaka; Charernmak, Boonsri; Phengmak, Manthana; Jitpiboon, Walailuk; Geater, Alan Frederick
2018-04-25
Tuberculous meningitis (TBM) is the most severe form of extra-pulmonary tuberculosis. The definite diagnosis of this disease is difficult and can result in delayed treatment. Conventional culture yields low sensitivity while high-sensitivity diagnostic techniques are costly and unpractical. Adenosine deaminase (ADA) is used to diagnose several settings of extra-pulmonary tuberculosis but it is limited in TBM especially among HIV-infected patients. We retrospectively reviewed the data of patients with non-suppurative meningitis and compared the patient data with TBM and other causes including carcinomatous, lymphomatous, lymphocytic and fungal meningitis. We found that HIV infection, diabetes mellitus, duration of symptoms <14 days, radiologic findings of hydrocephalus, and CSF ADA level >10 IU were associated with TBM. The scoring system based on these parameters and their coefficients in the final model achieved an area under the receiver operating characteristic curve of 0.95,625. The indices were HIV infection = 5, diabetes mellitus = 3, duration of symptoms <14 days = 5, hydrocephalus = 4, and ADA in CSF >10 IU = 5. Based on the assumed costs of the patients with false negative and false positive, an appropriate cut off value of 10 was selected and the sensitivity was 92% and specificity was 89%. Copyright © 2018 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.