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Diagnostic Tests (diagnostic + test)
Kinds of Diagnostic Tests Terms modified by Diagnostic Tests Selected AbstractsRENIN STIMULATION TEST: A SIMPLE DIAGNOSTIC TEST FOR HYPERALDOSTERONISMNEPHROLOGY, Issue 3 2000Penny Mj [source] The Use of a Rapid Diagnostic Test to Determine Malaria as a Cause of DeathJOURNAL OF TRAVEL MEDICINE, Issue 6 2003François Chappuis No abstract is available for this article. [source] The Weighted Generalized Estimating Equations Approach for the Evaluation of Medical Diagnostic Test at Subunit LevelBIOMETRICAL JOURNAL, Issue 5 2006Carol Y. Lin Abstract Sensitivity and specificity are common measures used to evaluate the performance of a diagnostic test. A diagnostic test is often administrated at a subunit level, e.g. at the level of vessel, ear or eye of a patient so that the treatment can be targeted at the specific subunit. Therefore, it is essential to evaluate the diagnostic test at the subunit level. Often patients with more negative subunit test results are less likely to receive the gold standard tests than patients with more positive subunit test results. To account for this type of missing data and correlation between subunit test results, we proposed a weighted generalized estimating equations (WGEE) approach to evaluate subunit sensitivities and specificities. A simulation study was conducted to evaluate the performance of the WGEE estimators and the weighted least squares (WLS) estimators (Barnhart and Kosinski, 2003) under a missing at random assumption. The results suggested that WGEE estimator is consistent under various scenarios of percentage of missing data and sample size, while the WLS approach could yield biased estimators due to a misspecified missing data mechanism. We illustrate the methodology with a cardiology example. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Diagnosis of Nonmelanoma Skin Cancer/Keratinocyte Carcinoma: A Review of Diagnostic Accuracy of Nonmelanoma Skin Cancer Diagnostic Tests and TechnologiesDERMATOLOGIC SURGERY, Issue 10 2007METTE MOGENSEN MD BACKGROUND Nonmelanoma skin cancer (NMSC) is the most prevalent cancer in the light-skinned population. Noninvasive treatment is increasingly used for NMSC patients with superficial lesions, making the development of noninvasive diagnostic technologies highly relevant. OBJECTIVE The scope of this review is to present data on the current state-of-the-art diagnostic methods for keratinocyte carcinoma: basal cell carcinoma, squamous cell carcinoma, and actinic keratosis. METHODS AND MATERIALS MEDLINE, BIOSIS, and EMBASE searches on NMSC and physical and clinical examination, biopsy, molecular marker, ultrasonography, Doppler, optical coherence tomography, dermoscopy, spectroscopy, fluorescence imaging, confocal microscopy, positron emission tomography, computed tomography, magnetic resonance imaging, terahertz imaging, electrical impedance and sensitivity, specificity, and diagnostic accuracy. RESULTS State-of-the-art diagnostic research has been limited in this field, but encouraging results from the reviewed diagnostic trials have suggested a high diagnostic accuracy for many of the technologies. Most of the studies, however, were pilot or small studies and the results would need to be validated in larger trials. CONCLUSIONS Some of these new imaging technologies have the capability of providing new, three-dimensional in vivo, in situ understanding of NMSC development over time. Some of the new technologies described here have the potential to make it from the bench to the clinic. [source] Validation of Diagnostic Tests for Helicobacter pylori with Regard to Grade of Atrophic Gastritis and/or Intestinal MetaplasiaHELICOBACTER, Issue 6 2009Cheol Min Shin Abstract Background and Aims:, To evaluate the validity of the biopsy-based tests (histology, culture, and urease test) and serology in detecting current Helicobacter pylori infection against a background of atrophic gastritis (AG) or intestinal metaplasia (IM). Methods:,Helicobacter pylori infection was diagnosed in 651 subjects, using the predefined gold standard for H. pylori tests. The sensitivity, specificity, and positive and negative predictive values of culture, CLOtest, histology (Giemsa stain), and serology were calculated with regard to the histological grade of AG and IM. The level of serum pepsinogen (PG) I and II was also measured as a marker for the presence of AG. Results:, In the study population (n = 651), sensitivity and specificity, respectively, were as follows: culture, 56.2 and 100%; histology, 93.0 and 94.0%; CLOtest, 80.4 and 96.7%; serology, 96.0 and 67.5%. If the analysis is limited to those without AG or IM (n = 158) or to those younger than 40 years (n = 69), all tests, except for culture, had a sensitivity and specificity >90%. The sensitivity of CLOtest and the specificity of serology markedly decreased with progression of AG and IM, and serology was less specific in the presence of AG, as determined by a PG I/II ratio ,4.1 (specificity, 83.7% vs 40.7% in PG I/II >4.1 and ,4.1, respectively). Conclusions:, Any one of biopsy-based tests or serology was found to be excellent for identifying current H. pylori infection among individuals without AG or IM and/or younger patients (<40 years). However, a combination of at least two tests is necessary in the clinical setting of AG or IM. [source] Problems of Developing Molecular Diagnostic Tests for Opportunistic Pathogens: The Example of Pneumocystis jiroveciiTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 2006JIM F. HUGGETT [source] Profile-Likelihood Inference for Highly Accurate Diagnostic TestsBIOMETRICS, Issue 4 2002John V. Tsimikas Summary. We consider profile-likelihood inference based on the multinomial distribution for assessing the accuracy of a diagnostic test. The methods apply to ordinal rating data when accuracy is assessed using the area under the receiver operating characteristic (ROC) curve. Simulation results suggest that the derived confidence intervals have acceptable coverage probabilities, even when sample sizes are small and the diagnostic tests have high accuracies. The methods extend to stratified settings and situations in which the ratings are correlated. We illustrate the methods using data from a clinical trial on the detection of ovarian cancer. [source] PhadiatopTM compared to skin-prick test as a tool for diagnosing atopy in epidemiological studies in schoolchildrenPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2007Luis Garcia-Marcos The validity of the PhadiatopTM test as compared to the skin-prick test (SPT) for diagnosing atopy in the epidemiological field has not been studied in schoolchildren. The aim of the present study was to evaluate its validity for classifying schoolchildren 9,12 yr old into atopics and non-atopics. A total of 621 children whose parents authorized both a SPT and a blood extraction from all children participating in the phase II of the International Study of Allergies in Children (ISAAC) in Cartagena (Spain) were included in the analysis. A positive SPT was that with at least a wheal having a maximum diameter of 3 mm, once the negative value had been subtracted. PhadiatopTM was performed according to the manufacturer instructions. Diagnostic tests using SPT as the gold standard were calculated for the whole group of children and also for those with asthma or rhinoconjunctivitis and for children without any of them. The results of the tests were: sensitivity 85.0% (95% CI 82.2,87.8%), specificity 85.5% (95%CI 82.7,88.3%), positive predictive value 72.7% (95%CI 69.0,76.1%), negative predictive value 92.7% (95%CI 90.6,94.7%) and accuracy 85.3% (95%CI 82.3,88.0%). The results improved among the symptomatic groups. PhadiatopTM can be used as a valid alternative to SPT in the epidemiological setting to diagnose atopy. [source] Diagnostic tests for bias of estimating equations in weighted regression with missing covariatesTHE CANADIAN JOURNAL OF STATISTICS, Issue 2 2001S.-Y. Claire Lei Abstract The authors propose two tests, one parametric and the other semiparametric, for testing bias of estimating equations in weighted regression with partially missing covariates when the primary regression model is correctly specified. More generally, the proposed tests may be thought of as a diagnostic tool for the combined package of the primary regression model and the missingness assumptions. The asymptotic null distributions of the two test statistics are derived under the assumption of missingness at random for the partially missing covariates. A small scale simulation study completes the work. [source] Meta-Analysis of Diagnostic Test Accuracy Studies with Multiple Thresholds using Survival MethodsBIOMETRICAL JOURNAL, Issue 1 2010H. Putter Abstract Diagnostic tests play an important role in clinical practice. The objective of a diagnostic test accuracy study is to compare an experimental diagnostic test with a reference standard. The majority of these studies dichotomize test results into two categories: negative and positive. But often the underlying test results may be categorized into more than two, ordered, categories. This article concerns the situation where multiple studies have evaluated the same diagnostic test with the same multiple thresholds in a population of non-diseased and diseased individuals. Recently, bivariate meta-analysis has been proposed for the pooling of sensitivity and specificity, which are likely to be negatively correlated within studies. These ideas have been extended to the situation of diagnostic tests with multiple thresholds, leading to a multinomial model with multivariate normal between-study variation. This approach is efficient, but computer-intensive and its convergence is highly dependent on starting values. Moreover, monotonicity of the sensitivities/specificities for increasing thresholds is not guaranteed. Here, we propose a Poisson-correlated gamma frailty model, previously applied to a seemingly quite different situation, meta-analysis of paired survival curves. Since the approach is based on hazards, it guarantees monotonicity of the sensitivities/specificities for increasing thresholds. The approach is less efficient than the multinomial/normal approach. On the other hand, the Poisson-correlated gamma frailty model makes no assumptions on the relationship between sensitivity and specificity, gives consistent results, appears to be quite robust against different between-study variation models, and is computationally very fast and reliable with regard to the overall sensitivities/specificities. [source] Diagnostic tests for congenital cytomegalovirus infectionACTA PAEDIATRICA, Issue 10 2010RS Gandhi No abstract is available for this article. [source] Hypocretin/orexin and narcolepsy: new basic and clinical insightsACTA PHYSIOLOGICA, Issue 3 2010S. Nishino Abstract Narcolepsy is a chronic sleep disorder, characterized by excessive daytime sleepiness (EDS), cataplexy, sleep paralysis and hypnagogic hallucinations. Both sporadic (95%) and familial (5%) forms of narcolepsy exist in humans. The major pathophysiology of human narcolepsy has been recently discovered based on the discovery of narcolepsy genes in animals; the genes involved in the pathology of the hypocretin/orexin ligand and its receptor. Mutations in hypocretin-related genes are rare in humans, but hypocretin ligand deficiency is found in a large majority of narcolepsy with cataplexy. Hypocretin ligand deficiency in human narcolepsy is probably due to the post-natal cell death of hypocretin neurones. Although a close association between human leucocyte antigen (HLA) and human narcolepsy with cataplexy suggests an involvement of autoimmune mechanisms, this has not yet been proved. Hypocretin deficiency is also found in symptomatic cases of narcolepsy and EDS with various neurological conditions, including immune-mediated neurological disorders, such as Guillain,Barre syndrome, MA2-positive paraneoplastic syndrome and neuromyelitis optica (NMO)-related disorder. The findings in symptomatic narcoleptic cases may have significant clinical relevance to the understanding of the mechanisms of hypocretin cell death and choice of treatment option. The discoveries in human cases lead to the establishment of the new diagnostic test of narcolepsy (i.e. low cerebrospinal fluid hypocretin-1 levels for ,narcolepsy with cataplexy' and ,narcolepsy due to medical condition'). As a large majority of human narcolepsy patients are ligand deficient, hypocretin replacement therapy may be a promising new therapeutic option, and animal experiments using gene therapy and cell transplantations are in progress. [source] Lymphocyte transformation test as a diagnostic test in allergic contact dermatitisCONTACT DERMATITIS, Issue 4 2005Hans F. Merk No abstract is available for this article. [source] Screening for gestational diabetes; past, present and futureDIABETIC MEDICINE, Issue 5 2002F. W. F. Hanna Abstract Gestational diabetes is carbohydrate intolerance, with onset or first recognition of hyperglycaemia during pregnancy. Several studies have suggested that gestational hyperglycaemia is associated with adverse maternal and fetal outcomes, promoting the case for screening. Conversely, others argue that screening for gestational diabetes may colour the clinical judgement, influencing further management, e.g. more ,unjustified' caesarean sections. Additionally, the lack of definitive data either on a clear-cut glycaemic threshold for the development of adverse outcomes or on the impact of intervention is emphasized by opponents of screening. This review attempts to evaluate the available data on screening for gestational diabetes. Oral glucose tolerance test is promoted on the basis that the diabetogenic stress of pregnancy is encountered during late gestation and is best recognized in the fed state. There are different tests, including the 1 h/50-g, 2 h/75-g and 3 h/100-g tests, with practical limitations, including the time and cost involved and the unpleasant supra-physiological glucose load that is unrelated to body weight, and issues of reproducibility and sensitivity/specificity profiles. Despite its convenience, the poor sensitivity of random glucose has precluded its routine use for screening. Fasting glucose appears to be promising but further testing is required to ensure satisfactory sensitivity/specificity in different populations. Despite its limitations, the oral glucose tolerance test has become established as the ,most acceptable' diagnostic test for gestational diabetes. More convenient methods, e.g. fasting or random or post-load glucose, have to be validated therefore against the oral glucose tolerance test to gain acceptance for routine screening. Diabet. Med 19, 351,358 (2002) [source] Exfoliative sputum cytology of cancers metastatic to the lung,DIAGNOSTIC CYTOPATHOLOGY, Issue 3 2005Tehmina Z. Ali M.D. Abstract Although largely replaced by fine-needle aspiration (FNA) and bronchoscopy, cytological examination of sputum for exfoliated malignant cells still is considered a valuable initial diagnostic test in patients presenting with a lung mass. Thirty-five cases of secondary/metastatic tumors involving the lung and diagnosed on sputum were retrospectively reviewed from our cytopathology files for a period of 22 yr (1980,2001). Clinical history and the relevant histopathological material were examined and correlated with the cytological findings. In all cases, a history of malignancy was known. Cytological diagnoses included colonic adenocarcinoma (7 cases); non-Hodgkin's lymphoma (NHL; 5 cases); malignant melanoma (MM; 5 cases); breast carcinoma (5 cases); Hodgkin's lymphoma (HL; 3 cases); pancreatic adenocarcinoma (2 cases); prostatic adenocarcinoma (2 cases); and 1 case each of urothelial carcinoma, endometrial carcinoma, renal cell carcinoma, hepatic small-cell carcinoma, squamous-cell carcinoma (cervix), and leiomyosarcoma (LMS). Cellular preservation was optimal in all cases. The smear background was relatively clean in 25 (71%) cases and predominantly inflamed and/or necrotic in 10 (29%) cases. In non-lymphoid tumors (27 cases), isolated single malignant cells were seen in 7 (26%) cases (all cases of MM and prostatic adenocarcinoma), whereas 20 (74%) cases displayed fragments with intact tumor architecture. Overall, only 10/35 (29%) cases showed noticeable tumor-cell necrosis. In one case (LMS), cell block sections were used for immunoperoxidase (IPOX) studies with positive staining for desmin and actin. Exfoliation of cancer cells in sputum from secondary tumors in the lung is a rare phenomenon in current-day practice, with metastatic colonic adenocarcinoma seen most commonly. Intact tumor architecture was observed in exfoliated cells in 75% of the cases. Diagn. Cytopathol. 2005;33:147,151. © 2005 Wiley-Liss, Inc. [source] SPLENIC RUPTURE FOLLOWING ROUTINE COLONOSCOPYDIGESTIVE ENDOSCOPY, Issue 4 2010Tabraze Rasul Splenic rupture is a life-threatening condition characterized by internal hemorrhage, often difficult to diagnose. Colonoscopy is a gold standard routine diagnostic test to investigate patients with gastrointestinal symptoms as well as to those on the screening program for colorectal cancer. Splenic injury is seldomly discussed during consent for colonoscopy, as opposed to colonic perforation, as its prevalence accounts for less than 0.1%. A 66-year-old Caucasian woman with no history of collagen disorder was electively admitted for routine colonoscopy for surveillance of adenoma. She was admitted following the procedure for re-dosing of warfarin, which was stopped prior to the colonoscopy. The patient was found collapsed on the ward the following day with clinical shock and anemia. Computed tomography demonstrated grade 4 splenic rupture. Immediate blood transfusion and splenectomy was required. Splenic rupture following routine colonoscopy is extremely rare. Awareness of it on this occasion saved the patient's life. Despite it being a rare association, the seriousness warrants inclusion in all information leaflets concerning colonoscopy and during its consent. [source] The role of electrophoresis in disease biomarker discoveryELECTROPHORESIS, Issue 12 2007Haleem J. Issaq Dr. Abstract There has been increased activity in the last few years in the search for disease markers using fractionation of complex biological fluids combined with MS. While electrophoretic and chromatographic separations have played a major role in this endeavor, this manuscript is limited to a review of electrophoretic methods that have been established for disease biomarker discovery. These methods include 2-DE, difference gel electrophoresis (DIGE), and CE. We define what constitutes a biomarker, identify the steps required for establishing a biomarker, and describe the parameters needed in the design of an ideal diagnostic test. The application, advantages, and limitations of CE, DIGE, and 2-DE in meeting the goal of discovering novel biomarkers is discussed in detail, along with a few selected examples that illustrate the search for biomarkers for cancer and neurological diseases. [source] Evaluation of PG-M3 antibody in the diagnosis of acute promyelocytic leukaemiaEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 10 2010Sanjeev Kumar Gupta Eur J Clin Invest 2010; 40 (10): 960,962 Abstract Background & objectives, Acute promyelocytic leukaemia (APL) is a distinct subtype of acute myeloid leukaemia (AML) characterized by a reciprocal translocation, t(15;17) and a high incidence of life-threatening coagulopathy. APL diagnosis is considered a medical emergency. As reverse transcription-polymerase chain reaction (RT-PCR) for PML-RAR, fusion oncoprotein is time consuming, there is a need for a rapid and accurate diagnostic test for APL. This study evaluates the role of PG-M3 monoclonal antibody using immunofluorescence (IF) in the early diagnosis of APL. Materials and Methods, Thirty-six new untreated APL cases diagnosed with RT-PCR for PML-RAR, as the gold standard and 38 non-APL controls (28 non-APL AMLs and 10 non-leukaemic samples) were evaluated by routine morphology and cytochemistry, RT-PCR and IF using PG-M3 monoclonal antibody. Results, Using IF, 34 of 36 (94·4%) APL cases showed a microgranular pattern suggestive of APL and two cases (5·6%) showed a speckled pattern typical of wild-type PML protein (False negative). By comparison, two of 28 (7·1%) non-APL AMLs showed microgranular pattern (false positive). Hence, IF as a diagnostic test for APL resulted in a sensitivity of 94·4%, specificity of 92·9% and positive and negative predictive values of 94·4% and 92·9% respectively. All 10 non-leukaemic samples showed a speckled pattern. Conclusions, IF using PG-M3 antibodies can be used as a rapid (takes 2 h), cheap, sensitive and specific method to identify APL. It can be a useful adjunct for diagnosis of APL especially if facilities for RT-PCR are not available, particularly in resource-limited settings. [source] Hyperefficient PrPSc amplification of mouse-adapted BSE and scrapie strain by protein misfolding cyclic amplification techniqueFEBS JOURNAL, Issue 10 2009Aiko Fujihara Abnormal forms of prion protein (PrPSc) accumulate via structural conversion of normal PrP (PrPC) in the progression of transmissible spongiform encephalopathy. Under cell-free conditions, the process can be efficiently replicated using in vitro PrPSc amplification methods, including protein misfolding cyclic amplification. These methods enable ultrasensitive detection of PrPSc; however, there remain difficulties in utilizing them in practice. For example, to date, several rounds of protein misfolding cyclic amplification have been necessary to reach maximal sensitivity, which not only take several weeks, but also result in an increased risk of contamination. In this study, we sought to further promote the rate of PrPSc amplification in the protein misfolding cyclic amplification technique using mouse transmissible spongiform encephalopathy models infected with either mouse-adapted bovine spongiform encephalopathy or mouse-adapted scrapie, Chandler strain. Here, we demonstrate that appropriate regulation of sonication dramatically accelerates PrPSc amplification in both strains. In fact, we reached maximum sensitivity, allowing the ultrasensitive detection of < 1 LD50 of PrPSc in the diluted brain homogenates, after only one or two reaction rounds, and in addition, we detected PrPSc in the plasma of mouse-adapted bovine spongiform encephalopathy-infected mice. We believe that these results will advance the establishment of a fast, ultrasensitive diagnostic test for transmissible spongiform encephalopathies. [source] Penile pharmacotesting in diagnosing male erectile dysfunction: evidence for lack of accuracy and specificityINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 1 2002Antonio Aversa Penile pharmacotesting (PPT) with alprostadil (PGE1) represents the most common diagnostic approach to male erectile dysfunction (ED). A positive response , i.e. normal erectile rigidity of sustained duration , is presumed to exclude venous or arterial pathology with enough accuracy. To test this assumption we compared PPT vs. flowmetric results obtained by colour-duplex Doppler ultrasound (CDDU) in patients (pts) undergoing diagnostic evaluation for ED under conditions of maximal cavernous relaxation. A total of 195 non-consecutive impotent pts were diagnosed after dynamic CDDU as non-vasculogenic (NOR), or having arteriogenic (AR), veno-occlusive (VO) or mixed (MX) ED. Maximal erection obtained after PPT was scored as: type-1 (full tumescence , no sustained rigidity, angle on the abdominal plane >90°), type-2 (sustained partial erection, valid for intromission, angle=90°) and type-3 (sustained full erection, angle <90°). Comparing PPT with flowmetric results, we found that a type-3 response had 20% false negative diagnosis of NOR (17% of AR- and 3% of VO- and MX-ED, respectively), while a type-2 response had 63% false negative diagnosis (20% of AR, 37% of VO- and 6% MX-ED, respectively). Type-1 response was associated with the presence of VO dysfunction in 99% of cases. These data suggest that a positive response to PPT (type-2 and type-3) assessed by the visual rating of erection is associated with both arterial (up to 20%) and/or VO (up to 43%) ED, as detected by CDDU. We conclude that PPT alone is a misleading diagnostic test to exclude vascular ED and that dynamic CDDU should be offered to pts investigated for male ED. [source] Transversus abdominis plane block as a diagnostic testACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2010M. R. Lefort No abstract is available for this article. [source] Comparison of the Tzanck test and polymerase chain reaction in the diagnosis of cutaneous herpes simplex and varicella zoster virus infectionsINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 11 2007Atilla Ozcan MD Background, Although the diagnosis of herpes simplex virus (HSV) and varicella zoster virus (VZV) infections is usually made clinically, the Tzanck test, electron microscopy, viral culture, polymerase chain reaction (PCR), and serologic tests can be utilized to verify the diagnosis. Methods, We conducted a study on a total of 98 patients (77 patients with recurrent herpes simplex and 21 patients with herpes zoster) to evaluate the reliability and reproducibility of the Tzanck test in comparison with PCR. Results, In herpes virus infections, the general positivity rates of the Tzanck test and PCR were 61.2% and 79.6%, respectively. The difference between the positivity rates of the two tests was statistically significant. The positivity rates of the tests differed according to the type and duration of the lesions. Conclusions, Although PCR was superior to the Tzanck test, the Tzanck test has also been proven to be a reliable diagnostic method, with a sensitivity of 76.9% and a specificity of 100%. We recommend the use of this easy, quick, reproducible, and inexpensive diagnostic test more often in dermatologic practice, especially in cutaneous herpes virus infections. [source] Evaluation of an indirect serum ELISA and a bacteriological faecal culture test for diagnosis of Salmonella serotype Dublin in cattle using latent class modelsJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2004L.R. Nielsen Abstract Aims:, To evaluate a conventional bacteriological test based on faecal culture and an indirect serum ELISA for detection of S. Dublin infected cattle. To compare the predictive values of the two tests in relation to the prevalence. Methods and Results:, A total of 4531 paired samples from cattle in 29 dairy herds were analysed for presence of S. Dublin bacteria in faeces and immunoglobulins directed against S. Dublin lipopolysaccharide in an indirect serum ELISA. Sensitivity and specificity were estimated at two ELISA cut-off values using a validation method based on latent class models, which presumably provides less biased results than traditional validation methods. Stratification of data into three age groups gave significantly better estimates of test performance of the ELISA. Receiver operating characteristic (ROC) curves were constructed for comparison of overall performance of the ELISA between the three age groups. The sensitivity of the faecal culture test was low (6,14%). ELISA appeared to have a higher validity for animals aged 100,299 days of age than older or younger animals. Overall, the negative predictive value of the ELISA was 2,10 times higher than for the faecal culture test at realistic prevalence of infection in the test population. Conclusions:, The diagnostic sensitivity of the faecal culture test for detection of S. Dublin is poor, the specificity is 1. The superior sensitivity and negative predictive value of the serum ELISA makes this test preferable to faecal culture as an initial screening test and for certification of herds not infected with S. Dublin. Significance and Impact of the Study:, A quantitative estimate of the sensitivity of a faecal culture test for S. Dublin in a general population was provided. ELISA was shown to be an appropriate alternative diagnostic test. Preferably, samples from animals aged 100,299 days of age should be used as these give the best overall performance of the ELISA. Plots of ROC curves and predictive values in relation to prevalence facilitates optimisation of the ELISA cut-off value. [source] S100A8/A9: A Potential New Diagnostic Aid for Acute AppendicitisACADEMIC EMERGENCY MEDICINE, Issue 3 2010John F. Bealer MD Abstract Objectives:, Diagnosing acute appendicitis is a daunting clinical challenge, as there is no single test that reliably distinguishes acute appendicitis from other etiologies of acute abdominal pain. In this study, the authors examined whether circulating levels of S100A8/A9 could be useful as a marker to aid in the diagnosis of acute appendicitis. Methods:, Plasma samples from emergency department (ED) patients with acute abdominal pain (n = 181) were tested using an immunoassay for S100A8/A9. Results:, The sensitivity and specificity for S100A8/A9 in diagnosing acute appendicitis were estimated to be 93% (95% confidence interval [CI] = 81% to 97%) and 54% (95% CI = 45% to 62%), respectively. Negative predictive value (NPV) was 96% (95% CI = 89% to 99%), and positive predictive value (PPV) was 37% (95% CI = 28% to 47%). Performance characteristics of elevated white blood cell (WBC) count were also estimated: sensitivity 63% (95% CI = 47% to 76%), specificity 67% (95% CI = 59% to 75%), NPV 86% (95% CI = 78% to 91%), and PPV 36% (95% CI = 26% to 47%). Conclusions:, This is the first report exploring the relationship between circulating S100A8/A9 and acute appendicitis and establishes proof of concept for this biomarker as a diagnostic test for acute appendicitis. Further studies are indicated to optimize the use of this biomarker, in conjunction with other established approaches. ACADEMIC EMERGENCY MEDICINE 2010; 17:333,336 © 2010 by the Society for Academic Emergency Medicine [source] Hypothermic cardiopulmonary bypass as a determinant of late thrombocytopenia following cardiac operations in pediatric patientsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 8 2009M. RANUCCI Background: Thrombocytopenia after cardiac operations is a common event in both adult and pediatric patients. Late thrombocytopenia (LTCP) is a less common event that is still without a well-recognized cause. This study explores the role of heparin-induced thrombocytopenia (HIT) and other factors (complexity of the operation, temperature management, and drug use) in determining LTCP. Methods: We conducted an observational study of 63 consecutive patients aged <36 months operated with or without cardiopulmonary bypass (CPB). LTCP was defined as a platelet count <100,000 cells/,l or <50% of the pre-operative count at any point in time between post-operative days 5 and 10. A diagnostic test for heparin-platelet factor 4 (PF4) antibodies was performed in patients with LTCP. Other pre- and post-operative factors were investigated for their association with LTCP. Results: LTCP occurred in 15 (24%) patients. No patient had positive heparin-PF4 antibodies. The lowest temperature on CPB was an independent predictor of LTCP, with a cut-off value at 29 °C (sensitivity 80%, specificity 70%). Other factors associated with LTCP were prolonged post-operative use of unfractionated heparin and milrinone. LTCP was associated with increased post-operative morbidity. Conclusion: LTCP was related to a combination of factors (operation severity, degree of hypothermia during CPB, prolonged use of unfractionated heparin, and milrinone). The individual contribution of each factor seems difficult to establish. However, the degree of hypothermia during CPB and drug-associated effects were identified. HIT could be excluded in all cases. [source] Sonography of the rotator cuff in painful shoulders performed without knowledge of clinical information: Results from 58 sonographic examinations with surgical correlationJOURNAL OF CLINICAL ULTRASOUND, Issue 1 2007Stefan Moosmayer MD Abstract Purpose. To assess the value of sonography as an isolated diagnostic test for the detection and quantification of rotator cuff tears. Methods. Preoperative sonographic examination was performed on 58 shoulders. Key biases on sonographic interpretation such as history-taking, physical examination, or concurrent imaging examinations were excluded by way of blinding. Tears of the rotator cuff were the positive findings of interest. Assessment of tear size and localization was done sonographically, and the results were compared with operative findings. Results. All 24 full-thickness tears observed at surgery had been diagnosed correctly via sonography. In 19 of 20 cases with an intact rotator cuff, preoperative sonography was negative. Thirteen of 14 partial-thickness tears were not detected via sonography; 1 was misinterpreted as a full-thickness tear. Location of the tears relative to the rotator cuff tendons was described correctly in 21 of 25 cases. For tear size measurement, the 95% range of agreement was less than ±1 cm. Conclusions. Blinded sonographic examination is effective in the detection and quantification of full-thickness tears of the rotator cuff but lacks sensitivity in the detection of partial-thickness tears. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 2007 [source] Measurement of HbA1c from stored whole blood samples in the Atherosclerosis Risk in Communities studyJOURNAL OF DIABETES, Issue 2 2010Elizabeth SELVIN Abstract Background:, The aims of the present study were to demonstrate the reliability of HbA1c measurements during two time periods and to compare these measurements with HbA1c distribution in the general US population. Methods:, HbA1c was measured in 14 069 whole blood samples in the Atherosclerosis Risk in Communities (ARIC) study using different HPLC instruments across two time periods, namely 2003,2004 and 2007,2008. At the time of measurement, samples had been in storage at ,70°C for up to 18 years. To assess differences in values, HbA1c measurements were repeated in 383 samples at both periods. Indirect comparisons were made by comparing our measurements against those from a nationally representative study. Results:, The coefficients of variation for quality control samples were 1.8% (n = 89) in 2003,2004 and 1.4% (n = 259) in 2007,2008. The correlation between measurements at the two time points was high (r = 0.99), but with a slight bias: 0.29% points higher in 2007,2008 vs 2003,2004 (n = 383; P < 0.0001). The comparison yielded the following Deming regression equation: y(2007,2008) = 0.073 + 1.034x(2003,2004). After alignment using this equation, the distribution of HbA1c in the ARIC study was similar to that in the national study using fresh samples. Conclusions:, Measurements of HbA1c from samples stored for up to 18 years are highly reliable when using state-of-the-art HPLC instruments, but with some bias introduced over time. The HbA1c data now available in the ARIC study should be invaluable for investigations into the clinical utility of HbA1c as a diagnostic test for diabetes. [source] Detection of spring viraemia of carp virus (SVCV) by loop-mediated isothermal amplification (LAMP) in koi carp, Cyprinus carpio LJOURNAL OF FISH DISEASES, Issue 4 2008R B Shivappa Abstract Spring viraemia of carp virus (SVCV) is a rhabdovirus associated with systemic illness and mortality in cyprinids. Several diagnostic tests are available for detection of SVCV. However, most of these tests are time consuming and are not well adapted for field-based diagnostics. In this study, a diagnostic tool for SVCV detection based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) has been developed. Based on the nucleotide sequence of the glycoprotein (G) gene of SVCV North Carolina (NC) isolate, four sets (each set containing two outer and two inner) of primers were designed. Temperature and time conditions were optimized to 65 °C and 60 min, respectively, for LAMP and RT-LAMP using one primer set. In vitro specificity was evaluated using four different strains of fish rhabdoviruses and RT-LAMP was found to be specific to SVCV. Serial dilutions of SVCV NC isolate was used to evaluate the in vitro sensitivity of RT-LAMP. Sensitivity of the assays was similar to RT-PCR and detected SVCV even at the lowest dilution of 101 TCID50 mL,1. The ability of RT-LAMP to detect SVCV from infected carp was also tested and the assay detected SVCV from all infected fish. The isothermal temperature requirements, high specificity and sensitivity, and short incubation time of the RT-LAMP assay make it an excellent choice as a field diagnostic test for SVCV. [source] Molecular characterization of the fish-pathogenic fungus Aphanomyces invadansJOURNAL OF FISH DISEASES, Issue 5 2003J H Lilley Abstract Aphanomyces invadans (Saprolegniaceae) is a peronosporomycete fungus associated with the serious fish disease, epizootic ulcerative syndrome (EUS), also known as mycotic granulomatosis. In this study, interspecific relationships were examined between A. invadans isolates and other aquatic animal pathogenic Saprolegniaceae, and saprophytic Saprolegniaceae from EUS-affected areas. Restriction fragment length polymorphisms and sequences of ribosomal DNA confirmed that A. invadans is distinct from all other species studied. A sequence from the internal transcribed spacer region ITS1, unique to A. invadans, was used to design primers for a PCR-based diagnostic test. Intraspecific relationships were also examined by random amplification of polymorphic DNA using 20 isolates of A. invadans from six countries. The isolates showed a high degree of genetic homogeneity using 14 random ten-mer primers. This provides evidence that the fungus has spread across Asia in one relatively rapid episode, which is consistent with reports of outbreaks of EUS. Physiological distinctions between A. invadans and other Aphanomyces species based on a data set of 16 growth parameters showed remarkable taxonomic congruence with the molecular phylogeny. [source] An evaluation of current diagnostic tests for the detection of infectious salmon anaemia virus (ISAV) following experimental water-borne infection of Atlantic salmon, Salmo salar L.JOURNAL OF FISH DISEASES, Issue 3 2003M Snow Abstract Four commonly used diagnostic tests [reverse transcription polymerase chain reaction (RT-PCR), indirect fluorescent antibody test (IFAT), virus culture and light microscopy] were evaluated for their ability to detect infectious salmon anaemia virus (ISAV) or tissue pathology following experimental infection of Atlantic salmon. Fish were infected with ISAV by water-borne exposure which mimics the route of natural infection. Forty-five per cent of pre-clinical fish tested yielded positive results by RT-PCR for at least one of the organs tested (kidney, heart, gill, liver, blood). No significant difference was detected between organs in the number or time of first occurrence of positive result. Virus culture identified a total of 14% of pre-clinical fish as ISAV-infected. The presence of ISAV in heart tissue was particularly notable (13% of fish sampled) as was the inability to culture virus from spleen tissue. In the case of IFAT, 15% of fish sampled were positive, although tissue other than kidney proved unsuitable for use in this method. Only limited ISAV-specific pathology was detectable by histological examination of fish prior to the onset of clinical disease. These findings reveal important information regarding the optimal choice of both tissue sample and diagnostic test for the routine diagnosis of ISAV. [source] | ||||||||||||||||||||||||||||||||||||||||||||||