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Sample records for sensitive diagnostic test

  1. Local Sensitivity and Diagnostic Tests

    NARCIS (Netherlands)

    Magnus, J.R.; Vasnev, A.L.

    2004-01-01

    In this paper we confront sensitivity analysis with diagnostic testing.Every model is misspecified, but a model is useful if the parameters of interest (the focus) are not sensitive to small perturbations in the underlying assumptions. The study of the e ect of these violations on the focus is

  2. Efficient Noninferiority Testing Procedures for Simultaneously Assessing Sensitivity and Specificity of Two Diagnostic Tests

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    Guogen Shan

    2015-01-01

    Full Text Available Sensitivity and specificity are often used to assess the performance of a diagnostic test with binary outcomes. Wald-type test statistics have been proposed for testing sensitivity and specificity individually. In the presence of a gold standard, simultaneous comparison between two diagnostic tests for noninferiority of sensitivity and specificity based on an asymptotic approach has been studied by Chen et al. (2003. However, the asymptotic approach may suffer from unsatisfactory type I error control as observed from many studies, especially in small to medium sample settings. In this paper, we compare three unconditional approaches for simultaneously testing sensitivity and specificity. They are approaches based on estimation, maximization, and a combination of estimation and maximization. Although the estimation approach does not guarantee type I error, it has satisfactory performance with regard to type I error control. The other two unconditional approaches are exact. The approach based on estimation and maximization is generally more powerful than the approach based on maximization.

  3. Dose-response assessments of Kathon biocide (I). Diagnostic use and diagnostic threshold patch testing with sensitized humans.

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    Weaver, J E; Cardin, C W; Maibach, H I

    1985-03-01

    Nearly all effective, commercially available preservatives possess skin sensitization potential. This manuscript describes a program of diagnostic patch and practical use testing of consumer products that contained Kathon CG, a relatively new biocide. A series of threshold diagnostic patch tests demonstrated that the minimal elicitation concentration in occluded patch testing of allergic subjects considerably exceeded the concentrations of the biocide typically present in normal diluted use of the test products. Use testing further confirmed a threshold exposure for eliciting allergic reactions. It showed that even subjects who have delayed contact hypersensitivity to Kathon CG used rinse-off personal care products preserved with this agent without experiencing elicitation of these allergies.

  4. The Hug-up Test: A New, Sensitive Diagnostic Test for Supraspinatus Tears

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    Yu-Lei Liu

    2016-01-01

    Full Text Available Background: The supraspinatus tendon is the most commonly affected tendon in rotator cuff tears. Early detection of a supraspinatus tear using an accurate physical examination is, therefore, important. However, the currently used physical tests for detecting supraspinatus tears are poor diagnostic indicators and involve a wide range of sensitivity and specificity values. Therefore, the aim of this study was to establish a new physical test for the diagnosis of supraspinatus tears and evaluate its accuracy in comparison with conventional tests. Methods: Between November 2012 and January 2014, 200 consecutive patients undergoing shoulder arthroscopy were prospectively evaluated preoperatively. The hug-up test, empty can (EC test, full can (FC test, Neer impingement sign, and Hawkins-Kennedy impingement sign were used and compared statistically for their accuracy in terms of supraspinatus tears, with arthroscopic findings as the gold standard. Muscle strength was precisely quantified using an electronic digital tensiometer. Results: The prevalence of supraspinatus tears was 76.5%. The hug-up test demonstrated the highest sensitivity (94.1%, with a low negative likelihood ratio (NLR, 0.08 and comparable specificity (76.6% compared with the other four tests. The area under the receiver operating characteristic curve for the hug-up test was 0.854, with no statistical difference compared with the EC test (z = 1.438, P = 0.075 or the FC test (z = 1.498, P = 0.067. The hug-up test showed no statistical difference in terms of detecting different tear patterns according to the position (χ2 = 0.578, P = 0.898 and size (Fisher′s exact test, P > 0.999 compared with the arthroscopic examination. The interobserver reproducibility of the hug-up test was high, with a kappa coefficient of 0.823. Conclusions: The hug-up test can accurately detect supraspinatus tears with a high sensitivity, comparable specificity, and low NLR compared with the conventional

  5. Sensitive KIT D816V mutation analysis of blood as a diagnostic test in mastocytosis

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    Kielsgaard Kristensen, Thomas; Vestergaard, Hanne; Bindslev-Jensen, Carsten

    2014-01-01

    The recent progress in sensitive KIT D816V mutation analysis suggests that mutation analysis of peripheral blood (PB) represents a promising diagnostic test in mastocytosis. However, there is a need for systematic assessment of the analytical sensitivity and specificity of the approach in order...... to establish its value in clinical use. We therefore evaluated sensitive KIT D816V mutation analysis of PB as a diagnostic test in an entire case-series of adults with mastocytosis. We demonstrate for the first time that by using a sufficiently sensitive KIT D816V mutation analysis, it is possible to detect...... the mutation in PB in nearly all adult mastocytosis patients. The mutation was detected in PB in 78 of 83 systemic mastocytosis (94%) and 3 of 4 cutaneous mastocytosis patients (75%). The test was 100% specific as determined by analysis of clinically relevant control patients who all tested negative. Mutation...

  6. A Highly Sensitive Rapid Diagnostic Test for Chagas Disease That Utilizes a Recombinant Trypanosoma cruzi Antigen

    Science.gov (United States)

    Barfield, C. A.; Barney, R. S.; Crudder, C. H.; Wilmoth, J. L.; Stevens, D. S.; Mora-Garcia, S.; Yanovsky, M. J.; Weigl, B. H.; Yanovsky, J.

    2011-01-01

    Improved diagnostic tests for Chagas disease are urgently needed. A new lateral flow rapid test for Chagas disease is under development at PATH, in collaboration with Laboratorio Lemos of Argentina, which utilizes a recombinant antigen for detection of antibodies to Trypanosoma cruzi. To evaluate the performance of this test, 375 earlier characterized serum specimens from a region where Chagas is endemic were tested using a reference test (the Ortho T. cruzi ELISA, Johnson & Johnson), a commercially available rapid test (Chagas STAT-PAK, Chembio), and the PATH–Lemos rapid test. Compared to the composite reference tests, the PATH–Lemos rapid test demonstrated an optimal sensitivity of 99.5% and specificity of 96.8%, while the Chagas STAT-PAK demonstrated a sensitivity of 95.3% and specificity of 99.5%. These results indicate that the PATH–Lemos rapid test shows promise as an improved and reliable tool for screening and diagnosis of Chagas disease. PMID:21342808

  7. Diagnostic Accuracy, Sensitivity, and Specificity of Executive Function Tests in Moderate Traumatic Brain Injury in Ghana.

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    Adjorlolo, Samuel

    2016-04-27

    The sociocultural differences between Western and sub-Saharan African countries make it imperative to standardize neuropsychological tests in the latter. However, Western-normed tests are frequently administered in sub-Saharan Africa because of challenges hampering standardization efforts. Yet a salient topical issue in the cross-cultural neuropsychology literature relates to the utility of Western-normed neuropsychological tests in minority groups, non-Caucasians, and by extension Ghanaians. Consequently, this study investigates the diagnostic accuracy, sensitivity, and specificity of executive function (EF) tests (The Stroop Test, Trail Making Test, and Controlled Oral Word Association Test), and a Revised Quick Cognitive Screening Test (RQCST) in a sample of 50 patients diagnosed with moderate traumatic brain injury and 50 healthy controls in Ghana. The EF test scores showed good diagnostic accuracy, with area under the curve (AUC) values of the Trail Making Test scores ranging from .746 to .902. With respect to the Stroop Test scores, the AUC values ranged from .793 to .898, while Controlled Oral Word Association Test had AUC value of .787. The RQCST scores discriminated between the groups, with AUC values ranging from .674 to .912. The AUC values of composite EF score and a neuropsychological score created from EF and RQCST scores were .936 and. 942, respectively. Additionally, the Stroop Test, Trail Making Test, EF composite score, and RQCST scores showed good to excellent sensitivities and specificities. In general, this study has shown that commonly used EF tests in Western countries have diagnostic accuracy, sensitivity, and specificity when administered in Ghanaian samples. The findings and implications of the study are discussed. © The Author(s) 2016.

  8. The diagnostic sensitivity of dengue rapid test assays is significantly enhanced by using a combined antigen and antibody testing approach.

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    Scott R Fry

    2011-06-01

    Full Text Available BACKGROUND: Serological tests for IgM and IgG are routinely used in clinical laboratories for the rapid diagnosis of dengue and can differentiate between primary and secondary infections. Dengue virus non-structural protein 1 (NS1 has been identified as an early marker for acute dengue, and is typically present between days 1-9 post-onset of illness but following seroconversion it can be difficult to detect in serum. AIMS: To evaluate the performance of a newly developed Panbio® Dengue Early Rapid test for NS1 and determine if it can improve diagnostic sensitivity when used in combination with a commercial IgM/IgG rapid test. METHODOLOGY: The clinical performance of the Dengue Early Rapid was evaluated in a retrospective study in Vietnam with 198 acute laboratory-confirmed positive and 100 negative samples. The performance of the Dengue Early Rapid in combination with the IgM/IgG Rapid test was also evaluated in Malaysia with 263 laboratory-confirmed positive and 30 negative samples. KEY RESULTS: In Vietnam the sensitivity and specificity of the test was 69.2% (95% CI: 62.8% to 75.6% and 96% (95% CI: 92.2% to 99.8 respectively. In Malaysia the performance was similar with 68.9% sensitivity (95% CI: 61.8% to 76.1% and 96.7% specificity (95% CI: 82.8% to 99.9% compared to RT-PCR. Importantly, when the Dengue Early Rapid test was used in combination with the IgM/IgG test the sensitivity increased to 93.0%. When the two tests were compared at each day post-onset of illness there was clear differentiation between the antigen and antibody markers. CONCLUSIONS: This study highlights that using dengue NS1 antigen detection in combination with anti-glycoprotein E IgM and IgG serology can significantly increase the sensitivity of acute dengue diagnosis and extends the possible window of detection to include very early acute samples and enhances the clinical utility of rapid immunochromatographic testing for dengue.

  9. New Exercise-Dipyridamole Combined Test for Nuclear Cardiology in Insufficient Effort: Appropriate Diagnostic Sensitivity Keeping Exercise Prognosis

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    Inés Vidal Cortinas

    2015-08-01

    Full Text Available AbstractBackground:Myocardial perfusion scintigraphy (MPS in patients not reaching 85% of the maximum predicted heart rate (MPHR has reduced sensitivity.Objectives:In an attempt to maintain diagnostic sensitivity without losing functional exercise data, a new exercise and dipyridamole combined protocol (EDCP was developed. Our aim was to evaluate the feasibility and safety of this protocol and to compare its diagnostic sensitivity against standard exercise and dipyridamole protocols.Methods:In patients not reaching a sufficient exercise (SE test and with no contraindications, 0.56 mg/kg of dipyridamole were IV administered over 1 minute simultaneously with exercise, followed by 99mTc-MIBI injection.Results:Of 155 patients, 41 had MPS with EDCP, 47 had a SE test (≥ 85% MPHR and 67 underwent the dipyridamole alone test (DIP. They all underwent coronary angiography within 3 months. The three stress methods for diagnosis of coronary lesions had their sensitivity compared. For stenosis ≥ 70%, EDCP yielded 97% sensitivity, SE 90% and DIP 95% (p = 0.43. For lesions ≥ 50%, the sensitivities were 94%, 88% and 95%, respectively (p = 0.35. Side effects of EDCP were present in only 12% of the patients, significantly less than with DIP (p < 0.001.Conclusions:The proposed combined protocol is a valid and safe method that yields adequate diagnostic sensitivity, keeping exercise prognostic information in patients unable to reach target heart rate, with fewer side effects than the DIP.

  10. New Exercise-Dipyridamole Combined Test for Nuclear Cardiology in Insufficient Effort: Appropriate Diagnostic Sensitivity Keeping Exercise Prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Cortinas, Inés Vidal, E-mail: invi@montevideo.com.uy; Beretta, Mario; Alonso, Omar; Mut, Fernando [Departamento de Medicina Nuclear do Hospital ‘Asociación Española’, Br. Artigas 1515, Montevideo (Uruguay)

    2015-08-15

    Myocardial perfusion scintigraphy (MPS) in patients not reaching 85% of the maximum predicted heart rate (MPHR) has reduced sensitivity. In an attempt to maintain diagnostic sensitivity without losing functional exercise data, a new exercise and dipyridamole combined protocol (EDCP) was developed. Our aim was to evaluate the feasibility and safety of this protocol and to compare its diagnostic sensitivity against standard exercise and dipyridamole protocols. In patients not reaching a sufficient exercise (SE) test and with no contraindications, 0.56 mg/kg of dipyridamole were IV administered over 1 minute simultaneously with exercise, followed by 99mTc-MIBI injection. Of 155 patients, 41 had MPS with EDCP, 47 had a SE test (≥ 85% MPHR) and 67 underwent the dipyridamole alone test (DIP). They all underwent coronary angiography within 3 months. The three stress methods for diagnosis of coronary lesions had their sensitivity compared. For stenosis ≥ 70%, EDCP yielded 97% sensitivity, SE 90% and DIP 95% (p = 0.43). For lesions ≥ 50%, the sensitivities were 94%, 88% and 95%, respectively (p = 0.35). Side effects of EDCP were present in only 12% of the patients, significantly less than with DIP (p < 0.001). The proposed combined protocol is a valid and safe method that yields adequate diagnostic sensitivity, keeping exercise prognostic information in patients unable to reach target heart rate, with fewer side effects than the DIP.

  11. What Is Diagnostic Testing?

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    ... you want to learn. Search form Search Diagnostic testing You are here Home Testing & Services Testing for ... help you make the decision. What Is Diagnostic Testing? Diagnostic genetic testing can usually work out if ...

  12. Sensitivity and specificity of in vitro diagnostic device used for influenza rapid test in Taiwan

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    Kun-Teng Wang

    2014-06-01

    Full Text Available The pandemic influenza A/H1N1 outbreak resulted in 18,449 deaths in over 214 countries. In Taiwan, the influenza rapid test, an in vitro diagnostic device (Flu-IVD, only requires documented reviews for market approval by the Taiwan Food and Drug Administration. The purpose of this study was to investigate the analytical sensitivity and specificity of Flu-IVDs used in Taiwan. Analytical sensitivity and specificity tests were performed for influenza antigens A/California/7/2009 (H1N1 virus, A/Victoria/210/2009 (H3N2 virus, B/Brisbane/60/08 virus, and human coronavirus OC43. A total of seven domestic and 31 imported Flu-IVD samples were collected, of which, 20 samples had inadequate labeling, including those with removed package inserts or incorrect insert information. The analytical sensitivity of Flu-IVDs for A/H1N1, A/H3N2, and Flu B was 500–1000 ng/mL, 1000 ng/mL, and 1000 ng/mL, respectively. For the 50% cell culture infective dose (CCID50 label, the average A/H1N1 and A/H3N2 sensitivity for Flu-IVDs was log10 5.8 ± 0.5 and log10 6.6 ± 0.5 CCID50/mL, respectively. As to the specificity test, no product cross-reacted with human coronavirus OC43. This study provides important information on the Flu-IVD regulation status and can thus help the government formulate policies for the regulation of in vitro diagnostic devices in Taiwan.

  13. 31P-MRS of skeletal muscle is not a sensitive diagnostic test for mitochondrial myopathy

    DEFF Research Database (Denmark)

    Jeppesen, Tina Dysgaard; Quistorff, Bjørn; Wibrand, Flemming

    2007-01-01

    Clinical phenotypes of persons with mitochondrial DNA (mtDNA) mutations vary considerably. Therefore, diagnosing mitochondrial myopathy (MM) patients can be challenging and warrants diagnostic guidelines. (31)phosphorous magnetic resonance spectroscopy ((31)P-MRS) have been included as a minor...... impaired citrate synthase-corrected complex I activity. Resting PCr/P(i) ratio and leg P(i) recovery were lower in MM patients vs. healthy subjects. PCr and ATP production after exercise were similar in patients and healthy subjects. Although the specificity for MM of some (31)P-MRS variables was as high...

  14. A better confidence interval for the sensitivity at a fixed level of specificity for diagnostic tests with continuous endpoints.

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    Shan, Guogen

    2017-02-01

    For a diagnostic test with continuous measurement, it is often important to construct confidence intervals for the sensitivity at a fixed level of specificity. Bootstrap-based confidence intervals were shown to have good performance as compared to others, and the one by Zhou and Qin (2005) was recommended as the best existing confidence interval, named the BTII interval. We propose two new confidence intervals based on the profile variance method and conduct extensive simulation studies to compare the proposed intervals and the BTII intervals under a wide range of conditions. An example from a medical study on severe head trauma is used to illustrate application of the new intervals. The new proposed intervals generally have better performance than the BTII interval.

  15. The Sensitivity, Specificity and Predictive Values of Snellen Chart Compared to the Diagnostic Test in Amblyopia Screening Program in Iran

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    Fatemeh Rivakani

    2015-12-01

    Full Text Available Introduction Amblyopia is a leading cause of visual impairment in both childhood and adult populations. Our aim in this study was to assess the epidemiological characteristics of the amblyopia screening program in Iran. Materials and Methods A cross-sectional study was done on a randomly selected sample of 4,636 Iranian children who were referred to screening program in 2013 were participated in validity study, too. From each provinces the major city were selected. Screening and diagnostic tests were done by instructors in first stage and optometrists in second stage, respectively. Finally data were analyzed by Stata version 13. Results The sensitivity was ranged from 74% to 100% among the various provinces such that Fars and Ardabil province had maximum and minimum values, respectively. The pattern of specificity was differ and ranged 44% to 84% among the provinces; Hormozgan and Fars had maximum and minimum values, respectively. The positive predictive value was also ranged from 35% to %81 which was assigned to Khuzestan and Ardabil provinces, respectively. The range of Negative Predictive value was 61% to 100% which was belonged to Ardabil and Fars provinces. Conclusion The total sensitivity (89% and negative predictive values (93% of screening test among children aged 3-6 years is acceptable, but only 51% of children refereed to second stage are true positive and this imposes considerable cost to health system.

  16. 1968 Prototype Diagnostic Test.

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    Veterans Administration Hospital, Bedford, MA.

    This true-false diagnostic test was used for pretesting of employees at a Veterans Administration Hospital. The test is comprised of 20 items. An alternate test--Classification Questionnaire--was used for testing after remedial training. (For related document, see TM 002 334.) (DB)

  17. Prenatal Genetic Diagnostic Tests

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    ... are available for many inherited disorders. The main disadvantage is that diagnostic testing carries a very small ... chromosomes, arranged in order of size. Microarray: A technology that examines all of a person’s genes to ...

  18. Estimation of Sensitivity and Specificity of Three Conditionally Dependent Diagnostic Tests in the Absence of a Gold Standard

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    Engel, B.; Swildens, B.; Stegeman, J.A.; Buist, W.G.; Jong, de M.

    2006-01-01

    This article presents a model to evaluate the accuracy of diagnostic tests. Data from three tests for the detection of EF-positive Streptococcus suis serotype 2 strains in sows were analyzed. The data were collected in a field study in the absence of a gold standard, that is, the true disease status

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

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

    2017-01-01

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

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

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    Daniel Chavarría-Bolaños

    2017-01-01

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

  1. Sensitivity is not an intrinsic property of a diagnostic test: empirical evidence from histological diagnosis of Helicobacter pylori infection

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    Carrilho Carla

    2009-12-01

    Full Text Available Abstract Background We aimed to provide empirical evidence of how spectrum effects can affect the sensitivity of histological assessment of Helicobacter pylori infection, which may contribute to explain the heterogeneity in prevalence estimates across populations with expectedly similar prevalence. Methods Cross-sectional evaluation of dyspeptic subjects undergoing upper digestive endoscopy, including collection of biopsy specimens from the greater curvature of the antrum for assessment of H. pylori infection by histopathological study and polymerase chain reaction (PCR, from Portugal (n = 106 and Mozambique (n = 102 following the same standardized protocol. Results In the Portuguese sample the prevalence of infection was 95.3% by histological assessment and 98.1% by PCR. In the Mozambican sample the prevalence was 63.7% and 93.1%, respectively. Among those classified as infected by PCR, the sensitivity of histological assessment was 96.2% among the Portuguese and 66.3% among the Mozambican. Among those testing positive by both methods, 5.0% of the Portuguese and 20.6% of the Mozambican had mild density of colonization. Conclusions This study shows a lower sensitivity of histological assessment of H. pylori infection in Mozambican dyspeptic patients compared to the Portuguese, which may be explained by differences in the density of colonization, and may contribute to explain the heterogeneity in prevalence estimates across African settings.

  2. DIAGNOSTIC KARATE TESTS

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    Dragan Doder

    2006-06-01

    Full Text Available The basic condition of a successful process of karate training is making diagnosis of any sportsman. Assessment is usually done by a coach and it is a part of technical process; quantity measurements are also a part of the evaluation which contains these tests. The suggested diagnostic karate tests are based on the knowledge of the specific karate characteristics and on the research which was done so far (Zulić 1985, Milošević and Zulić 1988, Jovanović 1981, 1988, Mudrić 1994, Doder 1998, 2000, 2005, Babiak, Doder, Savić, Golik2001, Savić, Doder, Babiak 2002. Karate as a type of sport demands diagnosis of many relevant characteristics, abilities and features that are thought to be predominant in the analysis of this kind of sport. Knowing all relevant anthropologic karate dimensions it is possible to select necessary instruments for measuring and to test those dimensions that karate results depend on. Considering all scientific knowledge and achievements in this field the fallowing tests are suggested: Morphologic measures: body height, arm span, arm length, pelvis width, hand ankle diameter, knees diameter, elbow diameter, body weight, parameters of one’s chest, stomach, the upper and lower part of one’s arm and legs, then to examine the skin fold of any sportsman’s arms, back, stomach and legs. Functional diagnosis: measuring of the maximum amount of oxygen breathed in. Mobility tests: the speed of simple movements, the speed of karate technique, deep bow on the bench, shoulders capability of moving, the static strength of hands, legs, shoulders and middle part of a body, jump height, an average jump, and the percentage of maximum achievement in jumping.

  3. Applications of a Rapid and Sensitive Dengue DUO Rapid Immunochromatographic Test Kit as a Diagnostic Strategy during a Dengue Type 2 Epidemic in an Urban City.

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    Shih, Hsin-I; Hsu, Hsiang-Chin; Wu, Chi-Jung; Lin, Chih-Hao; Chang, Chia-Ming; Tu, Yi-Fang; Hsieh, Chih-Chia; Chi, Chih-Hsien; Sung, Tzu-Ching

    2016-01-01

    Dengue infection is a major health problem in tropical and subtropical countries. A prospective observational study in a university-affiliated hospital was conducted between August 2015 and September 2015. Patients who visited the emergency department (ED) with a presentation of any symptoms of dengue were eligible for the dengue non-structural protein 1 (NS1), IgM/IgG rapid immunochromatographic tests and real-time polymerase chain reaction (RT-PCR) to evaluate the performance of the rapid tests. Considering the RT-PCR as the gold standard for the dengue diagnosis, the ideal primary results of sensitivity (80-100%), specificity (60-84%), positive predicted value(75%-95%), and negative predicted value (70-100%) suggested that the NS1-based test with or without a combination of IgM and IgG tests have good diagnostic performances in detecting dengue infections, even in the afebrile or elderly populations.

  4. Bayesian Estimation of the True Prevalence and of the Diagnostic Test Sensitivity and Specificity of Enteropathogenic Yersinia in Finnish Pig Serum Samples

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    M. J. Vilar

    2015-01-01

    Full Text Available Bayesian analysis was used to estimate the pig’s and herd’s true prevalence of enteropathogenic Yersinia in serum samples collected from Finnish pig farms. The sensitivity and specificity of the diagnostic test were also estimated for the commercially available ELISA which is used for antibody detection against enteropathogenic Yersinia. The Bayesian analysis was performed in two steps; the first step estimated the prior true prevalence of enteropathogenic Yersinia with data obtained from a systematic review of the literature. In the second step, data of the apparent prevalence (cross-sectional study data, prior true prevalence (first step, and estimated sensitivity and specificity of the diagnostic methods were used for building the Bayesian model. The true prevalence of Yersinia in slaughter-age pigs was 67.5% (95% PI 63.2–70.9. The true prevalence of Yersinia in sows was 74.0% (95% PI 57.3–82.4. The estimates of sensitivity and specificity values of the ELISA were 79.5% and 96.9%.

  5. Sensitive Diagnostics for Chemically Reacting Flows

    KAUST Repository

    Farooq, Aamir

    2015-11-02

    This talk will feature latest diagnostic developments for sensitive detection of gas temperature and important combustion species. Advanced optical strategies, such as intrapulse chirping, wavelength modulation, and cavity ringdown are employed.

  6. Diagnostic patch test concentration for Kathon CG.

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    Maibach, H I

    1985-10-01

    Patch test studies, 21-day cumulative irritancy assays and Draize repeat insult patch tests with Kathon CG, were used to ascertain an appropriate diagnostic patch test concentration. A dilution of 100 ppm a.i. (aq. or pet.) appears to have low irritancy potential. Further observations are required to verify if this concentration is high enough to detect most cases of sensitization.

  7. Novel, sensitive and low-cost diagnostic tests for 'river blindness'--detection of specific antigens in tears, urine and dermal fluid.

    Science.gov (United States)

    Ngu, J L; Nkenfou, C; Capuli, E; McMoli, T E; Perler, F; Mbwagbor, J; Tume, C; Nlatte, O B; Donfack, J; Asonganyi, T

    1998-05-01

    Sensitive, specific and low-cost diagnostic tests for onchocerciasis are indispensable for monitoring the efficacy of control programs, as well as for preventing blindness (when the tests are combined with efficacious chemotherapy. Three new tests to detect Onchocerca-specific antigens in tears, dermal fluid and urine employ antibodies to O. volvulus-specific recombinant proteins, Oncho-C27 and OvD3B, encoded by genes within the immunodominant Onchocerca OV 33-3 gene family, and expressed in yeast and in E. coli, respectively. In these assays, Onchocerca-specific antigens in test samples are bound onto a solid surface and revealed using appropriate enzyme-labelled antibodies. Proteins in the samples are first transferred to Hybond-N + membrane disks or nitrocellulose paper using either a transblot or a dotblot machine, and then reacted with specific O. volvulus antibodies. Bound antibodies are revealed with species-specific peroxidase-labelled antibodies and peroxidase substrate. Positive tests give a brown colour. In one of the two assays developed to detect Onchocerca antigens in tears, the sensitivity was enhanced by first adsorbing the specific antibodies onto the membrane surface in order to immobilize and concentrate the Onchocerca-specific antigen molecules on the membrane. The specificity of the recombinant proteins for Onchocerca volvulus had been verified by ELISA, classical Western blot and modified DSIA. The tests are a dipstick immunobinding assay for ocular microfilariae (DSIA), a transblot immunobinding assay for the detection of skin microfilariae (TADA) and a dot-blot immunobinding assay for detecting urinary microfilariae and their antigens (DIA). Their specificity and sensitivity were evaluated in the field on 110 subjects with proven ocular microfilariae, 130 subjects with clinical and parasitological evidence of onchocerciasis, 25 subjects infected with other helminths and 120 normal controls. The minimal detection limits of Oncho-C27 protein

  8. Component resolved testing for allergic sensitization

    DEFF Research Database (Denmark)

    Skamstrup Hansen, Kirsten; Poulsen, Lars K

    2010-01-01

    Component resolved diagnostics introduces new possibilities regarding diagnosis of allergic diseases and individualized, allergen-specific treatment. Furthermore, refinement of IgE-based testing may help elucidate the correlation or lack of correlation between allergenic sensitization and allergi...

  9. Latex glove sensitivity amongst diagnostic imaging healthcare ...

    African Journals Online (AJOL)

    kemrilib

    Latex glove sensitivity amongst diagnostic imaging healthcare personnel: a study in Southeastern Nigeria. Charles U. Eze1,* 1Augustine O. Okaro1 and Ivor C. Nwobi2. 1. Department of Medical Radiography and Radiological Sciences Faculty of Health Sciences and. Technology, University of Nigeria, Enugu Campus, ...

  10. Diagnostic tests based on human basophils

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    Kleine-Tebbe, Jörg; Erdmann, Stephan; Knol, Edward F

    2006-01-01

    -maximal responses, termed 'intrinsic sensitivity'. These variables give rise to shifts in the dose-response curves which, in a diagnostic setting where only a single antigen concentration is employed, may produce false-negative data. Thus, in order to meaningfully utilize the current basophil activation tests....... Diagnostic studies using CD63 or CD203c in hymenoptera, food and drug allergy are critically discussed. Basophil-based tests are indicated for allergy testing in selected cases but should only be performed by experienced laboratories....

  11. Diagnostic herd sensitivity using environmental samples

    DEFF Research Database (Denmark)

    Vigre, Håkan; Josefsen, Mathilde Hartmann; Seyfarth, Anne Mette

    be assessed. In this abstract we present an approach to evaluate the sensitivity of environmental samples used for herd classification. This is illustrated using results from samples for isolation of methicillin resistant Staphylococcus aureus (MRSA) in 48 pig herds that had previously been tested positive...... in the probability of isolating MRSA in the environmental samples by increasing within-herd prevalence. This relationship was strongest for dust where the sensitivity increased from 25% at 1% infected pigs, to 35% at a 25% infected pigs. The air sampling was more sensitive to detect infected herds irrespectively...

  12. Investigation and performance tests of a new parallel plate ionization chamber with double sensitive volume for measuring diagnostic X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Sharifi, B., E-mail: babak_sharifi88@yahoo.com [Graduate University of Advanced Technology, Kerman (Iran, Islamic Republic of); Zamani Zeinali, H. [Application of Radiation Research School, Nuclear Science and Technology Research Institute, AEOI, Karaj (Iran, Islamic Republic of); Soltani, J.; Negarestani, A. [Graduate University of Advanced Technology, Kerman (Iran, Islamic Republic of); Shahvar, A. [Application of Radiation Research School, Nuclear Science and Technology Research Institute, AEOI, Karaj (Iran, Islamic Republic of)

    2015-01-11

    Medical diagnostic equipment, like diagnostic radiology and mammography require a dosimeter with high accuracy for dosimetry of the diagnostic X-ray beam. Ionization chambers are suitable instruments for dosimetry of diagnostic-range X-ray beams because of their appropriate response and high reliability. This work introduces the design and fabrication of a new parallel plate ionization chamber with a PMMA body, graphite-coated PMMA windows (0.5 mm thick) and a graphite-foil central electrode (0.1 mm thick, 0.7 g/cm{sup 3} dense). This design improves upon the response characteristics of existing designs through the specific choice of materials as well as the appropriate size and arrangement of the ionization chamber components. The results of performance tests conducted at the Secondary Standard Dosimetry laboratory in Karaj-Iran demonstrated the short and long-term stability, the low leakage current, the low directional dependence, and the high ion collection efficiency of the design. Furthermore, the FLUKA Monte Carlo simulations confirmed the low effect of central electrode on this new ionization chamber response. The response characteristics of the parallel plate ionization chamber presented in this work makes the instrument suitable for use as a standard dosimeter in laboratories.

  13. Comparative Study of the Sensitivity of Different Diagnostic Methods for the Laboratory Diagnosis of Buruli Ulcer Disease

    NARCIS (Netherlands)

    Herbinger, Karl-Heinz; Adjei, Ohene; Awua-Boateng, Nana-Yaa; Nienhuis, Willemien A.; Kunaa, Letitia; Siegmund, Vera; Nitschke, Joerg; Thompson, William; Klutse, Erasmus; Agbenorku, Pius; Schipf, Alexander; Reu, Simone; Racz, Paul; Fleischer, Bernhard; Beissner, Marcus; Fleischmann, Erna; Helfrich, Kerstin; van der Werf, Tjip S.; Loescher, Thomas; Bretzel, Gisela

    2009-01-01

    Background. Several diagnostic laboratory methods are available for case confirmation of Buruli ulcer disease. This study assessed the sensitivity of various diagnostic tests in relation to clinical presentation of the disease, type of diagnostic specimen, and treatment history. Methods. Swab

  14. Systematic reviews of diagnostic test accuracy

    DEFF Research Database (Denmark)

    Leeflang, Mariska M G; Deeks, Jonathan J; Gatsonis, Constantine

    2008-01-01

    More and more systematic reviews of diagnostic test accuracy studies are being published, but they can be methodologically challenging. In this paper, the authors present some of the recent developments in the methodology for conducting systematic reviews of diagnostic test accuracy studies......-operating characteristic or the bivariate model for the data analysis. Challenges that remain are the poor reporting of original diagnostic test accuracy studies and difficulties with the interpretation of the results of diagnostic test accuracy research....

  15. Diagnostic Tests in Human Brucellosis

    Directory of Open Access Journals (Sweden)

    Hamid Reza Nouri

    2014-07-01

    Full Text Available Context: Brucellosis represents a zoonotic bacterial disease, caused by a gram negative bacterium called Brucella. Between the diverses pecies of this bacteria, B. melitensis, B. abortus, B. suis and B. canis consist the main causes of the disease in humans.More than half a million new cases of Brucellosis are reported annually. Consequently, brucellosis is a remarkable threat for the health of society. Because of the multiple nonspecific clinical signs of this infection, such as fever (60% of cases, night sweating, insomnia and anorexia, which are similar to other diseases, the detection of brucellosis is time-consuming and needs more scrutiny. Evidence Acquisition: Blood culture is considered the gold standard for the detection of brucellosis and the sensitivity of this test in the acute form is high. However, for the chronic type of disease, it is remarkably low, in addition, in some cases, it needs long reaction times. Nevertheless, today, some kinds of tests like automatic culturing system and serological methods, such as Rose Bengal (RB test, serum agglutination test (SAT, 2-mercaptoethanol (2ME and coombs, which are operated based on agglutination, are useful for the problems mentioned earlier. Conclusion: Although serological methods are common for the diagnosis of brucellosis, false results are observable for several methods, such as the SAT method. Tests like the enzyme-linked immunosorbent assay (ELISA, for the screening of specific traits, although confirmed, have their advantages and defects. The lateral flow assay (LFA shows promising evidence to be effective in the diagnosis of brucellosis. The polymerase chain reaction (PCR is more prevalent than other common tests, according to sensitivity and fast answering potency in case of molecular diagnosis. Also, PCR is proper for patients' follow-up during the period of treatment and crimination of relapse by this method is easier compared to others.

  16. Diagnostic efficacy of indirect hemagglutination test inrelation to ...

    African Journals Online (AJOL)

    BACKGROUND: Sensitive and specific diagnostic tools are very central to decide on individual case management and at all stages of control programs in schistosomiasis. This study was undertaken to assess the diagnostic efficacy of a commercial indirect hemagglutination test in detection of schistosomiasis mansoni in ...

  17. Re-test reliability of gustatory testing and introduction of the sensitive Taste-Drop-Test

    DEFF Research Database (Denmark)

    Fjaeldstad, A; Niklassen, A; Fernandes, H

    2018-01-01

    . Testing gustatory function can be important for diagnostics and assessment of treatment effects. However, the gustatory tests applied are required to be both sensitive and reliable.In this study, we investigate the re-test validity of popular Taste Strips gustatory test for gustatory screening....... Furthermore, we introduce a new sensitive Taste-Drop-Test, which was found to be superior for detecting a more accurate measure of tastant sensitivity....

  18. Best combination of multiple diagnostic tests for screening purposes.

    Science.gov (United States)

    Qin, Jing; Zhang, Biao

    2010-12-10

    In a medical diagnostic testing problem, multiple diagnostic tests are often available in distinguishing between diseased and nondiseased subjects. Different diagnostic tests are usually sensitive to different aspects of the disease. A desirable approach is to combine multiple diagnostic tests so as to obtain an optimal composite diagnostic test with higher sensitivity and specificity that detects the presence of the disease more accurately. To accomplish this, it has been observed via signal detection theory developed in the 1950s and 1960s, that the optimal combination of different diagnostic variables (i.e. the diagnostic test results) is determined by the likelihood ratio function for the diseased and nondiseased groups. The conventional approach is to fit parametric models for the diseased and nondiseased groups separately and then to use the fitted likelihood ratio function for the best combination of test results. However, this approach is not so robust if the underlying distribution functions are misspecified. Since the optimal combination depends only on the likelihood ratio function, it would be more appropriate to model this function directly. A two-sample semiparametric inference technique is applied to the model for the likelihood ratio function. We consider the best combination of multiple diagnostic tests, and study semiparametric likelihood estimation of the optimal receiver operating characteristic curve and the area under the curve. We present a bootstrap procedure along with some results on simulation and on analysis of two real data sets.

  19. outcome of presumptive versus rapid diagnostic tests

    African Journals Online (AJOL)

    GB

    2010-03-02

    Mar 2, 2010 ... diagnostic test in the management of children with this overlap, but this has not been evaluated. Therefore, the objective of this study was to compare the clinical outcome of presumptive versus malaria rapid diagnostic test - ... the rain forest belt of Nigeria, an area with perennial malaria trans mission.

  20. Optimizing diagnostic tests for persulphate

    DEFF Research Database (Denmark)

    Foss-Skiftesvik, Majken H; Winther, Lotte; Mosbech, Holger Fausbøll

    2016-01-01

    validated method of performing SIC with persulphate powder is time consuming with a duration of up to 4 days. The value of skin prick tests (SPTs) and histamine release tests (HRTs) with persulphates is unknown. The aim of this study was to establish a novel rapid SIC with persulphate powder to test...

  1. Diagnostic sensitivity for invasive cervical carcinoma of high risk HPV tests performed on SurePath™ liquid-based pap specimens

    Directory of Open Access Journals (Sweden)

    Nance KV

    2013-03-01

    Full Text Available Keith V NanceDepartment of Cytology, Rex Hospital, Raleigh, and Department of Pathology, The University of North Carolina School of Medicine, Chapel Hill, NC, USARecently I communicated with the Editor regarding Drs Naryshkin and Austins’ article entitled "Limitations of widely used high-risk human papillomavirus laboratory-developed testing in cervical carcinoma screening."1,2 As noted previously, this article is based on a single case report of squamous cell carcinoma of the cervix diagnosed in a patient who had abnormal Pap results but had negative Hybrid Capture 2 (HC2(Qiagen NV, Hilden, Germany high risk human papillomavirus (hrHPV testing from SurePath™ (Becton-Dickinson, Franklin Lakes, NJ, USA samples. The authors concluded that such testing should not be done using this collection medium. Interestingly, they also mentioned a 10% false negative rate for similar testing performed on FDA-approved Preservcyt® media on three of 31 invasive cervical carcinoma patients at Dr Austin’s own laboratory.View original paper by Naryshkin and Austin

  2. 9 CFR 93.406 - Diagnostic tests.

    Science.gov (United States)

    2010-01-01

    ... veterinarian issuing the certificate was authorized to do so, stating that: (1) Brucellosis. The cattle have... CONVEYANCE AND SHIPPING CONTAINERS Ruminants § 93.406 Diagnostic tests. (a) Tuberculosis and brucellosis tests of cattle. Except as provided in paragraph (d) of this section and in §§ 93.418, 93.427(d), and 93...

  3. Highly sensitive and multiplexed platforms for allergy diagnostics

    Science.gov (United States)

    Monroe, Margo R.

    Allergy is a disorder of the immune system caused by an immune response to otherwise harmless environmental allergens. Currently 20% of the US population is allergic and 90% of pediatric patients and 60% of adult patients with asthma have allergies. These percentages have increased by 18.5% in the past decade, with predicted similar trends for the future. Here we design sensitive, multiplexed platforms to detect allergen-specific IgE using the Interferometric Reflectance Imaging Sensor (IRIS) for various clinical settings. A microarray platform for allergy diagnosis allows for testing of specific IgE sensitivity to a multitude of allergens, while requiring only small volumes of patient blood sample. However, conventional fluorescent microarray technology is limited by i) the variation of probe immobilization, which hinders the ability to make quantitative, assertive, and statistically relevant conclusions necessary in immunodiagnostics and ii) the use of fluorophore labels, which is not suitable for some clinical applications due to the tendency of fluorophores to stick to blood particulates and require daily calibration methods. This calibrated fluorescence enhancement (CaFE) method integrates the low magnification modality of IRIS with enhanced fluorescence sensing in order to directly correlate immobilized probe (major allergens) density to allergen-specific IgE in patient serum. However, this platform only operates in processed serum samples, which is not ideal for point of care testing. Thus, a high magnification modality of IRIS was adapted as an alternative allergy diagnostic platform to automatically discriminate and size single nanoparticles bound to specific IgE in unprocessed, characterized human blood and serum samples. These features make IRIS an ideal candidate for clinical and diagnostic applications, such a POC testing. The high magnification (nanoparticle counting) modality in conjunction with low magnification of IRIS in a combined instrument

  4. Low sensitivity of glucagon provocative testing for diagnosis of pheochromocytoma.

    Science.gov (United States)

    Lenders, Jacques W M; Pacak, Karel; Huynh, Thanh-Truc; Sharabi, Yehonatan; Mannelli, Massimo; Bratslavsky, Gennady; Goldstein, David S; Bornstein, Stefan R; Eisenhofer, Graeme

    2010-01-01

    Pheochromocytomas can usually be confirmed or excluded using currently available biochemical tests of catecholamine excess. Follow-up tests are, nevertheless, often required to distinguish false-positive from true-positive results. The glucagon stimulation test represents one such test; its diagnostic utility is, however, unclear. The aim of the study was to determine the diagnostic power of the glucagon test to exclude or confirm pheochromocytoma. Glucagon stimulation tests were carried out at three specialist referral centers in 64 patients with pheochromocytoma, 38 patients in whom the tumor was excluded, and in a reference group of 36 healthy volunteers. Plasma concentrations of norepinephrine and epinephrine were measured before and after glucagon administration. Several absolute and relative test criteria were used for calculating diagnostic sensitivity and specificity. Expression of the glucagon receptor was examined in pheochromocytoma tumor tissue from a subset of patients. Larger than 3-fold increases in plasma norepinephrine after glucagon strongly predicted the presence of a pheochromocytoma (100% specificity and positive predictive value). However, irrespective of the various criteria examined, glucagon-provoked increases in plasma catecholamines revealed the presence of the tumor in less than 50% of affected patients. Diagnostic sensitivity was particularly low in patients with pheochromocytomas due to von Hippel-Lindau syndrome. Tumors from these patients showed no significant expression of the glucagon receptor. The glucagon stimulation test offers insufficient diagnostic sensitivity for reliable exclusion or confirmation of pheochromocytoma. Because of this and the risk of hypertensive complications, the test should be abandoned in routine clinical practice.

  5. A novel and accurate diagnostic test for human African trypanosomiasis.

    Science.gov (United States)

    Papadopoulos, Marios C; Abel, Paulo M; Agranoff, Dan; Stich, August; Tarelli, Edward; Bell, B Anthony; Planche, Timothy; Loosemore, Alison; Saadoun, Samira; Wilkins, Peter; Krishna, Sanjeev

    2004-04-24

    Human African trypanosomiasis (sleeping sickness) affects up to half a million people every year in sub-Saharan Africa. Because current diagnostic tests for the disease have low accuracy, we sought to develop a novel test that can diagnose human African trypanosomiasis with high sensitivity and specificity. We applied serum samples from 85 patients with African trypanosomiasis and 146 control patients who had other parasitic and non-parasitic infections to a weak cation exchange chip, and analysed with surface-enhanced laser desorption-ionisation time-of-flight mass spectrometry. Mass spectra were then assessed with three powerful data-mining tools: a tree classifier, a neural network, and a genetic algorithm. Spectra (2-100 kDa) were grouped into training (n=122) and testing (n=109) sets. The training set enabled data-mining software to identify distinct serum proteomic signatures characteristic of human African trypanosomiasis among 206 protein clusters. Sensitivity and specificity, determined with the testing set, were 100% and 98.6%, respectively, when the majority opinion of the three algorithms was considered. This novel approach is much more accurate than any other diagnostic test. Our report of the accurate diagnosis of an infection by use of proteomic signature analysis could form the basis for diagnostic tests for the disease, monitoring of response to treatment, and for improving the accuracy of patient recruitment in large-scale epidemiological studies.

  6. Immunochromatographic diagnostic test analysis using Google Glass.

    Science.gov (United States)

    Feng, Steve; Caire, Romain; Cortazar, Bingen; Turan, Mehmet; Wong, Andrew; Ozcan, Aydogan

    2014-03-25

    We demonstrate a Google Glass-based rapid diagnostic test (RDT) reader platform capable of qualitative and quantitative measurements of various lateral flow immunochromatographic assays and similar biomedical diagnostics tests. Using a custom-written Glass application and without any external hardware attachments, one or more RDTs labeled with Quick Response (QR) code identifiers are simultaneously imaged using the built-in camera of the Google Glass that is based on a hands-free and voice-controlled interface and digitally transmitted to a server for digital processing. The acquired JPEG images are automatically processed to locate all the RDTs and, for each RDT, to produce a quantitative diagnostic result, which is returned to the Google Glass (i.e., the user) and also stored on a central server along with the RDT image, QR code, and other related information (e.g., demographic data). The same server also provides a dynamic spatiotemporal map and real-time statistics for uploaded RDT results accessible through Internet browsers. We tested this Google Glass-based diagnostic platform using qualitative (i.e., yes/no) human immunodeficiency virus (HIV) and quantitative prostate-specific antigen (PSA) tests. For the quantitative RDTs, we measured activated tests at various concentrations ranging from 0 to 200 ng/mL for free and total PSA. This wearable RDT reader platform running on Google Glass combines a hands-free sensing and image capture interface with powerful servers running our custom image processing codes, and it can be quite useful for real-time spatiotemporal tracking of various diseases and personal medical conditions, providing a valuable tool for epidemiology and mobile health.

  7. Antiphospholipid Syndrome Laboratory Testing and Diagnostic Strategies

    Science.gov (United States)

    Ortel, Thomas L.

    2016-01-01

    The Antiphospholipid Syndrome (APS) is diagnosed in patients with recurrent thromboembolic events and/or pregnancy loss in the presence of persistent laboratory evidence for antiphospholipid antibodies. Diagnostic tests for the detection of antiphospholipid antibodies include laboratory assays that detect anticardiolipin antibodies, lupus anticoagulants, and anti-β2-glycoprotein I antibodies. These assays have their origins beginning more than sixty years ago, with the identification of the biologic false positive test for syphilis, the observation of ‘circulating anticoagulants’ in certain patients with systemic lupus erythematosus, the identification of cardiolipin as a key component in the serologic test for syphilis, and the recognition and characterization of a ‘cofactor’ for antibody binding to phospholipids. Although these assays have been used clinically for many years, there are still problems with the accurate diagnosis of patients with this syndrome. For example, lupus anticoagulant testing can be difficult to interpret in patients receiving anticoagulant therapy, but most patients with a thromboembolic event will already be anticoagulated before the decision to perform the tests has been made. In addition to understanding limitations of the assays, clinicians also need to be aware of which patients should be tested and not obtain testing on patients unlikely to have APS. New tests and diagnostic strategies are in various stages of development and should help improve our ability to accurately diagnose this important clinical disorder. PMID:22473619

  8. The Evaluation of Diagnostic Tests for Sexually Transmitted Infections

    Directory of Open Access Journals (Sweden)

    Max A Chernesky

    2005-01-01

    Full Text Available Diagnostic tests should receive method- and use-effectiveness evaluations. Method-effectiveness evaluations determine sensitivity, specificity and predictive values for new tests. Use-effectiveness evaluations determine how practical or convenient a new test will be in a specific setting and may not be performed in a formal way in North American laboratories. To perform a clinical method evaluation of diagnostic tests, a good relationship between laboratory and clinical personnel is essential. Studies are usually conducted separately on populations of men and women, and should include sampling from different prevalence groups. Test performance comparisons may be made on a single specimen type or on more than one specimen from the same patient, which allows for the expansion of a reference standard and includes the ability of a particular assay, performed on a specimen type to diagnose an infected individual. The following components of the evaluation should be standardized and carefully followed: specimen identification; collection; transportation; processing; quality control; reading; proficiency testing; confirmatory testing; discordant analysis -- sensitivity, specificity and predictive value calculations; and record keeping. Methods are available to determine whether sample results are true or false positives or negatives. Use-effectiveness evaluations might determine the stability or durability of supplies and equipment; the logistics of shipping, receiving and storing supplies; the clarity and completeness of test instructions; the time and effort required to process and read results; the subjectivity factors in interpretation and reporting; and the costs. These determinations are usually more apparent for commercial assays than for homemade tests.

  9. Diagnosis and diagnostic tests for fibromyalgia (syndrome).

    Science.gov (United States)

    Häuser, W; Wolfe, F

    2012-09-28

    To present diagnostic criteria for the clinical diagnosis of fibromyalgia syndrome (FMS) and to offer a scheme for diagnostic work-up in clinical practice. Narrative review of the literature, consensus documents by the American College of Rheumatology (ACR), evidence-based interdisciplinary German guidelines on the diagnosis and management of FMS. The ACR 1990 classification criteria emphasized tender points and widespread pain as the key features of FMS. In 2010, the ACR proposed preliminary diagnostic criteria for fibromyalgia that abandoned the tender point count and placed increased emphasis of patient symptoms. A later modification of the ACR 2010 criteria for use in surveys employed a self-report questionnaire (Fibromyalgia Survey Questionnaire FSQ) to assess patient symptoms. The FSQ can be used to assist physician's diagnosis of FMS. We recommend a stepwise diagnostic work-up of patients with chronic widespread pain (CWP) in primary care: Complete medical history including medication, complete medical examination, basic laboratory tests to screen for inflammatory or endocrinology diseases, referral to specialists only in case of suspected somatic diseases, assessment of limitations of daily functioning, screening for other functional somatic symptoms and mental disorders, and referring to mental health specialists in case of mental disorder. The diagnosis of FMS is easy in most patients with CWP and does not ordinarily require a rheumatologist. A rheumatologist's expertise might be needed to exclude difficult to diagnose or concomitant inflammatory rheumatic diseases. In the presence of mental illness referral to a mental health specialist for evaluation is recommended.

  10. Respiratory tests in diagnostics of Helicobacter pylori infection

    Directory of Open Access Journals (Sweden)

    Mayev I. V. Samsonov A.A. Ayvazova R.A. Rapoport S.I. Grechushnikov V.В.

    2013-03-01

    Full Text Available The Research Objective: Comparative assessment of informational content of various techniques, respiratory tests for Helicobacteriosis detection. Methods et methods: Research of existence of H.pylori in stomach has been conducted by respiratory tests in 106 patients with various diseases of stomach and duodenum. All researches have been conducted on an outpatient basis. Esophagogastroduodenoscopy with mucous biopsy and determination of H.pylori in biopsy materials have been followed by respiratory tests. Respiratory tests 13C UBT and 14C UBT have been carried out. The comparative analysis of respiratory tests for Helicobacteriosis detection has been performed. Results: The conducted researches have showed that, the respiratory tests are favourable for H.pylori diagnostics. They are methodically simple and short-term. Conclusion: Results of comparative researches showed that ammoniac respiratory tests for Helicobacteriosis detection in stomach possess lesser sensitivity than the 13C UBT — respiratory test and may be used for the primary diagnostics which results demand carrying out additional methods of diagnostics. Low specificity of these techniques and inauthentic results do not control the efficiency of eradication of H.pylori and do not present any value in medical examination of the population.

  11. Rapid diagnostic tests for typhoid and paratyphoid (enteric) fever.

    Science.gov (United States)

    Wijedoru, Lalith; Mallett, Sue; Parry, Christopher M

    2017-05-26

    hypothetical cohort of 1000 patients presenting with fever where 30% (300 patients) have enteric fever, on average Typhidot tests reporting indeterminate results or where tests do not produce indeterminate results will miss the diagnosis in 66 patients with enteric fever, TUBEX will miss 66, and Test-It Typhoid and prototype (KIT) tests will miss 93. In the 700 people without enteric fever, the number of people incorrectly diagnosed with enteric fever would be 161 with Typhidot tests, 91 with TUBEX, and 70 with Test-It Typhoid and prototype (KIT) tests. The CIs around these estimates were wide, with no difference in false positive results shown between tests.The quality of the data for each study was evaluated using a standardized checklist called QUADAS-2. Overall, the certainty of the evidence in the studies that evaluated enteric fever RDTs was low. In 37 studies that evaluated the diagnostic accuracy of RDTs for enteric fever, few studies were at a low risk of bias. The three main RDT tests and variants had moderate diagnostic accuracy. There was no evidence of a difference between the average sensitivity and specificity of the three main RDT tests. More robust evaluations of alternative RDTs for enteric fever are needed.

  12. Visualizing the impact of prevalence on a diagnostic test

    DEFF Research Database (Denmark)

    Rehling, Michael

    2010-01-01

    The purpose of a diagnostic test is to confirm or rule out disease or to increase or decrease the probability of disease. Only a few tests can separate all patients into those with and without a disease (true positive and true negative test). Usually there will be some false test results (false p....... This technical note brings a new illustration of the relative distribution of the four test results at prevalence from 0-1. The figure facilitates the understanding of the impact prevalence has on the predictive values of a clinical test.......The purpose of a diagnostic test is to confirm or rule out disease or to increase or decrease the probability of disease. Only a few tests can separate all patients into those with and without a disease (true positive and true negative test). Usually there will be some false test results (false...... positive and false negative). Traditionally, the four test results are given in a 2 by 2 table, and the terms sensitivity, specificity, and predictive values defined. The influence of the prevalence of the disease in question on the relative distribution of the four test results is not obvious...

  13. Ambulatory care sensitive conditions: diagnostic reliability in southern Brazil.

    Directory of Open Access Journals (Sweden)

    Rafael Antoniazzi Abaid

    2014-07-01

    Full Text Available Introduction: Ambulatory Care Sensitive Conditions (ACSC are illnesses that could be prevented with adjusted ambulatorial care. ACSC have been used as indicator in effectiveness of the primary healthcare attention, through the evaluation of hospital admissions. However, we do not have studies to certify the reliability of diagnosis of ACSC in our country. Objective: To determine if the classification of ACSC from the main diagnostic field of the authorization of hospital internment (AHI is reliable. Methods: Transversal study carried through February of 2010 to January of 2011, in the city of Santa Cruz of Sul (RS. A random sample of 389 medical records was selected and evaluated by two medical appraisers. The main diagnosis in the AHI was compared with the classification in ACSC or not ACSC given for the appraisers after the study of each medical record. Kappa ratio agreement was used to calculate the reliability of the ACSC diagnostic. Results: The ratio of agreement between diagnosis from the AIH and CSAP assessment contained in the records was 92%, with a kappa coefficient of 0,784. Conclusions: The diagnostic of ACSC found in main diagnostic field of AHI showed agreement ratios over expected by chance, with kappa value equal to 0.784 and the correlation rated between substantial and almost perfect.

  14. Diagnosis and diagnostic tests for fibromyalgia (syndrome

    Directory of Open Access Journals (Sweden)

    F. Wolfe

    2012-09-01

    Full Text Available Objectives: To present diagnostic criteria for the clinical diagnosis of fibromyalgia syndrome (FMS and to offer a scheme for diagnostic work-up in clinical practice. Methods: Narrative review of the literature, consensus documents by the American College of Rheumatology (ACR, evidence-based interdisciplinary German guidelines on the diagnosis and management of FMS. Results: The ACR 1990 classification criteria emphasized tender points and widespread pain as the key features of FMS. In 2010, the ACR proposed preliminary diagnostic criteria for fibromyalgia that abandoned the tender point count and placed increased emphasis of patient symptoms. A later modification of the ACR 2010 criteria for use in surveys employed a self-report questionnaire (Fibromyalgia Survey Questionnaire FSQ to assess patient symptoms. The FSQ can be used to assist physician’s diagnosis of FMS. We recommend a stepwise diagnostic work-up of patients with chronic widespread pain (CWP in primary care: Complete medical history including medication, complete medical examination, basic laboratory tests to screen for inflammatory or endocrinology diseases, referral to specialists only in case of suspected somatic diseases, assessment of limitations of daily functioning, screening for other functional somatic symptoms and mental disorders, and referring to mental health specialists in case of mental disorder. Conclusions: The diagnosis of FMS is easy in most patients with CWP and does not ordinarily require a rheumatologist. A rheumatologist’s expertise might be needed to exclude difficult to diagnose or concomitant inflammatory rheumatic diseases. In the presence of mental illness referral to a mental health specialist for evaluation is recommended.

  15. Divergence-based tests for model diagnostic

    Czech Academy of Sciences Publication Activity Database

    Hobza, Tomáš; Esteban, M. D.; Morales, D.; Marhuenda, Y.

    2008-01-01

    Roč. 78, č. 13 (2008), s. 1702-1710 ISSN 0167-7152 R&D Projects: GA MŠk 1M0572 Grant - others:Instituto Nacional de Estadistica (ES) MTM2006-05693 Institutional research plan: CEZ:AV0Z10750506 Keywords : goodness of fit * devergence statistics * GLM * model checking * bootstrap Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.445, year: 2008 http://library.utia.cas.cz/separaty/2008/SI/hobza-divergence-based%20tests%20for%20model%20diagnostic.pdf

  16. Diagnostic Accuracy of the Neck Tornado Test as a New Screening Test in Cervical Radiculopathy.

    Science.gov (United States)

    Park, Juyeon; Park, Woo Young; Hong, Seungbae; An, Jiwon; Koh, Jae Chul; Lee, Youn-Woo; Kim, Yong Chan; Choi, Jong Bum

    2017-01-01

    The Spurling test, although a highly specific provocative test of the cervical spine in cervical radiculopathy (CR), has low to moderate sensitivity. Thus, we introduced the neck tornado test (NTT) to examine the neck and the cervical spine in CR. The aim of this study was to introduce a new provocative test, the NTT, and compare the diagnostic accuracy with a widely accepted provocative test, the Spurling test. Retrospective study. Medical records of 135 subjects with neck pain (CR, n = 67; without CR, n = 68) who had undergone cervical spine magnetic resonance imaging and been referred to the pain clinic between September 2014 and August 2015 were reviewed. Both the Spurling test and NTT were performed in all patients by expert examiners. Sensitivity, specificity, and accuracy were compared for both the Spurling test and the NTT. The sensitivity of the Spurling test and the NTT was 55.22% and 85.07% ( P < 0.0001); specificity, 98.53% and 86.76% ( P = 0.0026); accuracy, 77.04% and 85.93% ( P = 0.0423), respectively. The NTT is more sensitive with superior diagnostic accuracy for CR diagnosed by magnetic resonance imaging than the Spurling test.

  17. A new position sensitive anode for plasmas diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Grasso, R., E-mail: grasso@lns.infn.it [INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, Catania 95123 (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Viale A. Doria 6, Catania 95125 (Italy); Tudisco, S. [INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, Catania 95123 (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Viale A. Doria 6, Catania 95125 (Italy); Anzalone, A. [INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, Catania 95123 (Italy); Musumeci, F.; Scordino, A. [INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, Catania 95123 (Italy); Dipartimento di Fisica ed Astronomia, Universita' di Catania, Viale A. Doria 6, Catania 95125 (Italy); Spitaleri, A. [INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, Catania 95123 (Italy); Anzalone, R.; D’Arrigo, G. [INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, Catania 95123 (Italy); IMM-Istituto per la Microelettronica e Microsistemi, CRN, VIII Strada 5 (Zona Industriale), Catania 95121 (Italy); LaVia, F. [IMM-Istituto per la Microelettronica e Microsistemi, CRN, VIII Strada 5 (Zona Industriale), Catania 95121 (Italy)

    2013-08-21

    The studies of plasmas generated by laser-matter interaction requires detectors that are able to perform the time resolved imaging of photons and charged particles. Such information are necessary in order to characterize the time evolution of fundamental parameters (as temperature, density, etc.) of plasma. One of the key elements of such diagnostics is the position sensitive anode. We are studying a new type of position-sensitive anode which will be realized by using silicon planar technology: a trapezes and stripes resistive anode (TSRA). The new TSRA is a two-dimensional system, which can be coupled with one of two-stage multichannel plates for the particles detection or for photons.

  18. Laboratory development and testing of spacecraft diagnostics

    Science.gov (United States)

    Amatucci, William; Tejero, Erik; Blackwell, Dave; Walker, Dave; Gatling, George; Enloe, Lon; Gillman, Eric

    2017-10-01

    The Naval Research Laboratory's Space Chamber experiment is a large-scale laboratory device dedicated to the creation of large-volume plasmas with parameters scaled to realistic space plasmas. Such devices make valuable contributions to the investigation of space plasma phenomena under controlled, reproducible conditions, allowing for the validation of theoretical models being applied to space data. However, in addition to investigations such as plasma wave and instability studies, such devices can also make valuable contributions to the development and testing of space plasma diagnostics. One example is the plasma impedance probe developed at NRL. Originally developed as a laboratory diagnostic, the sensor has now been flown on a sounding rocket, is included on a CubeSat experiment, and will be included on the DoD Space Test Program's STP-H6 experiment on the International Space Station. In this talk, we will describe how the laboratory simulation of space plasmas made this development path possible. Work sponsored by the US Naval Research Laboratory Base Program.

  19. Mirror fusion test facility plasma diagnostics system

    International Nuclear Information System (INIS)

    Thomas, S.R. Jr.; Coffield, F.E.; Davis, G.E.; Felker, B.

    1979-01-01

    During the past 25 years, experiments with several magnetic mirror machines were performed as part of the Magnetic Fusion Energy (MFE) Program at LLL. The latest MFE experiment, the Mirror Fusion Test Facility (MFTF), builds on the advances of earlier machines in initiating, stabilizing, heating, and sustaining plasmas formed with deuterium. The goals of this machine are to increase ion and electron temperatures and show a corresponding increase in containment time, to test theoretical scaling laws of plasma instabilities with increased physical dimensions, and to sustain high-beta plasmas for times that are long compared to the energy containment time. This paper describes the diagnostic system being developed to characterize these plasma parameters

  20. Screening for Wilson disease in acute liver failure: a comparison of currently available diagnostic tests

    DEFF Research Database (Denmark)

    Korman, J.D.; Volenberg, I.; Balko, J.

    2008-01-01

    yielded a sensitivity of 94%, specificity of 96%, and a likelihood ratio of 23 for diagnosing fulminant WD. In addition, an AST:ALT ratio >2.2 yielded a sensitivity of 94%, a specificity of 86%, and a likelihood ratio of 7 for diagnosing fulminant WD. Combining the tests provided a diagnostic sensitivity...

  1. Tuberculosis in Children: New diagnostic Blood Tests

    Directory of Open Access Journals (Sweden)

    F Kakkar

    2010-01-01

    Full Text Available The interferon-gamma-release assays were developed to overcome the pitfalls and logistic difficulties of the tuberculin skin test (TST for the diagnosis of latent tuberculosis infection (LTBI. These blood tests measure the in vitro production of interferon-gamma by sensitized lymphocytes in response to Mycobacterium tuberculosis-specific antigens. Two interferon-gamma-release assays are registered for use in Canada: the QuantiFERON-TB Gold In-Tube assay (Cellestis Inc, Australia and the T.SPOT–TB test (Oxford Immunotec, United Kingdom. Evaluation of these tests has been hampered by the lack of a gold standard for LTBI, and limited paediatric data on their use. It appears that they are more specific than the TST, and may be useful for evaluating TST-positive patients at low risk of true LTBI. Moreover, they may add sensitivity if used in addition to the TST in immunocompromised patients, very young children and close contacts of infectious adults. A summary of these tests, their limitations and their application to clinical paediatric practice are described.

  2. Concordance in diagnostic testing for respiratory pathogens of bighorn sheep

    Science.gov (United States)

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

    2016-01-01

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

  3. Retrospective evaluation of the consequence of alleged patch test sensitization

    DEFF Research Database (Denmark)

    Jensen, Charlotte D; Paulsen, Evy; Andersen, Klaus E

    2006-01-01

    consequences in cases of possible patch test sensitization. Among 7619 consecutively tested eczema patients in a 14-year period 26 (0.3%) were identified in the database as having had a late patch test reaction, which may be an indication of patch test sensitization. 9 of these cases were not suitable......The risk of actively sensitizing a patient in connection with diagnostic patch tests exists. This risk, however, is extremely low, especially from standard allergens, and if the test is carried out according to internationally accepted guidelines. This retrospective study investigates the clinical...... or available for the follow-up investigation and 3 patients were not traceable. Among the 14 remaining patients 1 had a reaction to gold sodium thiosulphate, which was assessed to be a persistent reaction and not a late reaction, and in 2 patients a clear relevance for the late reacting allergen was found...

  4. [Pathogenic Mechanism and Diagnostic Testing for Drug Allergies].

    Science.gov (United States)

    Uno, Katsuji

    2018-01-01

     Three stages of the pathogenic mechanism of drug allergies can be considered: antigen formation, immune reaction and inflammation/disorder reaction. Drugs are thought to form 4 types of antigens: drug only, polymers, drug-carrier conjugates, and metabolite-carrier complexes. Antigens are recognized by B cell receptors and T cell receptors. Helper T cells (Th) are differentiated into four subsets, namely, Th1, Th2, Th17 and regulatory T cells (Treg). Th1 produces interleukin (IL)-2 and interferon (IFN)-γ, and activates macrophages and cytotoxic T cells (Tc). Macrophages induce type IV allergies, and Tc lead to serious type IV allergies. On the other hand, Th2 produces IL-4, IL-5, and IL-6, etc., and activates B cells. B cells produce IgE antibodies, and the IgE antibody affects mast cells and induces type I allergies. Activated eosinophil leads to the chronic state of type I allergy. Diagnostic testing for allergenic drugs is necessary for patients with drug allergies. Because in vivo diagnostic tests for allergenic drugs are associated with a risk and burden to the patient, in vitro allergy tests are recommended to identify allergenic drugs. In allergy tests performed in vitro, cytological tests are more effective than serological tests, and the leukocyte migration test (LMT) presently has the highest efficacy. An LMT-chamber is better than LMT-agarose in terms of usability and sensitivity, and it can detect about 80% of allergenic drugs.

  5. Modern diagnostic capabilities for vasospastic angina diagnostics (intracoronary provocative testing

    Directory of Open Access Journals (Sweden)

    А. А. Обединский

    2017-04-01

    Full Text Available This review is devoted to a topical problem of modern cardiology – techniques of diagnosing vasospastic angina. The results of retrospective and prospective studies on the efficacy and safety of vasospastic angina diagnostics are reviewed. The literature on the prevalence, progression and treatment of this pathology is discussed.Received 13 January 2017. Accepted 6 February 2017.Financing: The study did not have sponsorship.Conflict of interest: The authors declare no conflict of interest.

  6. Modern diagnostic capabilities for vasospastic angina diagnostics (intracoronary provocative testing)

    OpenAIRE

    А. А. Обединский; С. В. Бугуров; О. В. Крестьянинов; И. А. Нарышкин; Д. Д. Зубарев; И. О. Гражданкин; Р. У. Ибрагимов; В. И. Байструков; Р. А. Найденов; Е. И. Кретов

    2017-01-01

    This review is devoted to a topical problem of modern cardiology – techniques of diagnosing vasospastic angina. The results of retrospective and prospective studies on the efficacy and safety of vasospastic angina diagnostics are reviewed. The literature on the prevalence, progression and treatment of this pathology is discussed.Received 13 January 2017. Accepted 6 February 2017.Financing: The study did not have sponsorship.Conflict of interest: The authors declare no conflict of interest.

  7. The performance of an Histidine rich protein-2 rapid diagnostic test ...

    African Journals Online (AJOL)

    Background: Malaria remains a major cause of morbidity and mortality, thus there is need for quick, reliable inexpensive diagnostic tool to facilitate its prompt treatment especially in resource poor settings. Objectives: To compare the sensitivity of a locally available Histidinerich protein-2 based rapid diagnostic test (RDT) ...

  8. Sensitivity study of a proposed polarimetry diagnostic on ASDEX upgrade

    International Nuclear Information System (INIS)

    Callaghan, H.P.; McCarthy, P.J.

    1994-09-01

    ASDEX-Upgrade currently uses FIR interferometry (DCN, 195 μm) as a technique for measuring line integrated electron density along eight chords of the plasma cross-section. A polarimetry diagnostic based on Faraday rotation using the existing setup would yield ∫ n e B.dl along the same chords which, in combination with the ∫ n e dl measurements, would provide additional information about the poloidal magnetic field. This would be helpful for reconstructing the q(ψ) profile, which is difficult to recover from external magnetic measurements alone. A sensitivity study to determine the effectiveness of adding polarimetry to ASDEX Upgrade is carried out using function parameterization on a simulated equilibrium database, together with a database of randomly chosen density profiles with four degrees of freedom. The robustness of the recovery in the presence of measurement noise and the effects of plasma birefringence are taken into account. (orig.)

  9. International regulatory requirements for skin sensitization testing.

    Science.gov (United States)

    Daniel, Amber B; Strickland, Judy; Allen, David; Casati, Silvia; Zuang, Valérie; Barroso, João; Whelan, Maurice; Régimbald-Krnel, M J; Kojima, Hajime; Nishikawa, Akiyoshi; Park, Hye-Kyung; Lee, Jong Kwon; Kim, Tae Sung; Delgado, Isabella; Rios, Ludmila; Yang, Ying; Wang, Gangli; Kleinstreuer, Nicole

    2018-03-05

    Skin sensitization test data are required or considered by chemical regulation authorities around the world. These data are used to develop product hazard labeling for the protection of consumers or workers and to assess risks from exposure to skin-sensitizing chemicals. To identify opportunities for regulatory uses of non-animal replacements for skin sensitization tests, the needs and uses for skin sensitization test data must first be clarified. Thus, we reviewed skin sensitization testing requirements for seven countries or regions that are represented in the International Cooperation on Alternative Test Methods (ICATM). We noted the type of skin sensitization data required for each chemical sector and whether these data were used in a hazard classification, potency classification, or risk assessment context; the preferred tests; and whether alternative non-animal tests were acceptable. An understanding of national and regional regulatory requirements for skin sensitization testing will inform the development of ICATM's international strategy for the acceptance and implementation of non-animal alternatives to assess the health hazards and risks associated with potential skin sensitizers. Copyright © 2018. Published by Elsevier Inc.

  10. A coproantigen diagnostic test for Strongyloides infection.

    Directory of Open Access Journals (Sweden)

    Alex M Sykes

    Full Text Available Accurate diagnosis of infection with the parasite Strongyloides stercoralis is hampered by the low concentration of larvae in stool, rendering parasitological diagnosis insensitive. Even if the more sensitive agar plate culture method is used repeated stool sampling is necessary to achieve satisfactory sensitivity. In this manuscript we describe the development of a coproantigen ELISA for diagnosis of infection. Polyclonal rabbit antiserum was raised against Strongyloides ratti excretory/secretory (E/S antigen and utilized to develop an antigen capture ELISA. The assay enabled detection of subpatent rodent S. ratti and human S. stercoralis infection. No cross-reactivity was observed with purified E/S from Schistosoma japonicum, the hookworms Ancylostoma caninum, A. ceylanicum, nor with fecal samples collected from rodents harboring Trichuris muris or S. mansoni infection. Strongyloides coproantigens that appear stable when frozen as formalin-extracted fecal supernatants stored at -20 °C remained positive up to 270 days of storage, whereas supernatants stored at 4 °C tested negative. These results indicate that diagnosis of human strongyloidiasis by detection of coproantigen is an approach worthy of further development.

  11. Transitioning high sensitivity cardiac troponin I (hs-cTnI) into routine diagnostic use: More than just a sensitivity issue

    LENUS (Irish Health Repository)

    Lee, Graham R

    2016-04-01

    High sensitivity cardiac troponin T and I (hs-cTnT and hs-cTnI) assays show analytical, diagnostic and prognostic improvement over contemporary sensitive cTn assays. However, given the importance of troponin in the diagnosis of myocardial infarction, implementing this test requires rigorous analytical and clinical verification across the total testing pathway. This was the aim of this study.

  12. Kathon CG: cosmetic allergy and patch test sensitization.

    Science.gov (United States)

    de Groot, A C; Liem, D H; Weyland, J W

    1985-02-01

    Three cases of contact allergy to Kathon CG, a preservative for cosmetics and toiletries containing, as active ingredients, 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one are presented. In two patients, Kathon CG was contained in a moisturizing cream, and the third was sensitized by a diagnostic patch test. Although it has been used extensively in cosmetics and toiletries for 9 years in Europe and 4 years in the USA, these appear to be the first case reports of non-occupational sensitization to Kathon CG.

  13. Diagnostic value of FIB-4 for liver fibrosis in patients with hepatitis B: a meta-analysis of diagnostic test.

    Science.gov (United States)

    Yin, Zhi; Zou, Jin; Li, Qiongxuan; Chen, Lizhang

    2017-04-04

    This study is aimed at evaluating the diagnostic value of FIB-4 for liver fibrosis in patients with hepatitis B through a meta-analysis of diagnostic test. We conducted a comprehensive search in the Pubmed, Embase, Web of Science, and Chinese National Knowledge Infrastructure before October 31, 2016. Stata 14.0 software was used for calculation and statistical analyses. We used the sensitivity, specificity, positive and negative likelihood ratio (PLR, NLR), diagnostic odds ratio (DOR) and 95% confidence intervals (CIs) to evaluate the diagnostic value of FIB-4 for liver fibrosis in patients with hepatitis B. Twenty-six studies were included in the final analyses, with a total of 8274 individuals. The pooled parameters are calculated from all studies: sensitivity of 0.69 (95%CI:0.63-0.75), specificity of 0.81 (95%CI: 0.73-0.87), PLR of 3.63 (95%CI:2.66-4.94), NLR of 0.38 (95%CI:0.32-0.44), DOR of 9.57 (95%CI: 6.67-13.74), and area under the curve (AUC) of 0.80 (95%CI: 0.76-0.83). We also conducted subgroup based on the range of cut-off values. Results from subgroup analysis showed that cut-off was the source of heterogeneity in the present study. The sensitivity and specificity of cut-off>2 were 0.69 and 0.95 with the AUC of 0.90 (95%CI: 0.87-0.92). The overall diagnostic value of FIB-4 is not very high for liver fibrosis in patients with hepatitis B. However, the diagnostic value is affected by the cut-off value. FIB-4 has relatively high diagnostic value for detecting liver fibrosis in patients with hepatitis B when the diagnostic threshold value is more than 2.0.

  14. Allergy or tolerance in children sensitized to peanut: prevalence and differentiation using component-resolved diagnostics.

    Science.gov (United States)

    Nicolaou, Nicolaos; Poorafshar, Maryam; Murray, Clare; Simpson, Angela; Winell, Henric; Kerry, Gina; Härlin, Annika; Woodcock, Ashley; Ahlstedt, Staffan; Custovic, Adnan

    2010-01-01

    Not all peanut-sensitized children develop allergic reactions on exposure. To establish by oral food challenge the proportion of children with clinical peanut allergy among those considered peanut-sensitized by using skin prick tests and/or IgE measurement, and to investigate whether component-resolved diagnostics using microarray could differentiate peanut allergy from tolerance. Within a population-based birth cohort, we ascertained peanut sensitization by skin tests and IgE measurement at age 8 years. Among sensitized children, we determined peanut allergy versus tolerance by oral food challenges. We used open challenge among children consuming peanuts (n = 45); others underwent double-blind placebo-controlled challenge (n = 34). We compared sensitization profiles between children with peanut allergy and peanut-tolerant children by using a microarray with 12 pure components (major peanut and potentially cross-reactive components, including grass allergens). Of 933 children, 110 (11.8%) were peanut-sensitized. Nineteen were not challenged (17 no consent). Twelve with a convincing history of reactions on exposure, IgE > or =15 kUa/L and/or skin test > or =8mm were considered allergic without challenge. Of the remaining 79 children who underwent challenge, 7 had > or =2 objective signs and were designated as having peanut allergy. We estimated the prevalence of clinical peanut allergy among sensitized subjects as 22.4% (95% CI, 14.8% to 32.3%). By using component-resolved diagnostics, we detected marked differences in the pattern of component recognition between children with peanut allergy (n = 29; group enriched with 12 children with allergy) and peanut-tolerant children (n = 52). The peanut component Ara h 2 was the most important predictor of clinical allergy. The majority of children considered peanut-sensitized on the basis of standard tests do not have peanut allergy. Component-resolved diagnostics may facilitate the diagnosis of peanut allergy. Copyright

  15. The Diagnostic Accuracy of Clinical Diagnostic Tests for Thoracic Outlet Syndrome.

    Science.gov (United States)

    Hixson, Krista M; Horris, Hannah B; McLeod, Tamara C Valovich; Bacon, Cailee E Welch

    2017-09-01

    Clinical Scenario: Thoracic outlet syndrome is quite challenging to diagnose. Currently, there are myriad diagnostic procedures used in the diagnosis of all types of thoracic outlet syndrome. However, controversy exists over which diagnostic procedures produce accurate findings. Can clinical diagnostic tests accurately diagnose patients presenting with symptoms of thoracic outlet syndrome? Summary of Key Findings: A thorough literature search returned 6 possible studies; 3 studies met the inclusion criteria and were included. Two studies supported the use of clinical diagnostic tests for the diagnosis of thoracic outlet syndrome. One study reported high false-positive rates among clinical diagnostic tests for thoracic outlet syndrome. One study reported that clinical diagnostic test findings correlate to provocative positioned magnetic resonance imaging findings. Clinical Bottom Line: There is moderate evidence to support the use of the Halstead maneuver (also known as the costoclavicular maneuver or exaggerated military brace test), Wright's test, Cyriax Release test, and supraclavicular pressure test to have good diagnostic accuracy for the provocation of symptoms in patients presenting with upper extremity pathology. However, these clinical diagnostic tests do not appear to allow for the differential diagnosis of thoracic outlet syndrome exclusively. The use of the Adson's test and Roos test should be discontinued for the differential diagnosis of thoracic outlet syndrome. Strength of Recommendation: Grade B evidence exists to support the accuracy of the Halstead maneuver, Wright's test, Cyriax Release test, and supraclavicular pressure test for the diagnosis of upper extremity pathology in general. Grade C evidence exists for the use of these clinical diagnostic tests to exclusively diagnose thoracic outlet syndrome.

  16. Diagnostic test systematic reviews: bibliographic search filters ("Clinical Queries") for diagnostic accuracy studies perform well.

    Science.gov (United States)

    Kastner, Monika; Wilczynski, Nancy L; McKibbon, Ann K; Garg, Amit X; Haynes, R Brian

    2009-09-01

    Systematic reviews of health care topics are valuable summaries of all pertinent studies on focused questions. However, finding all relevant primary studies for systematic reviews remains challenging. To determine the performance of the Clinical Queries sensitive search filter for diagnostic accuracy studies for retrieving studies for systematic reviews. We compared the yield of the sensitive Clinical Queries diagnosis search filter for MEDLINE and EMBASE to retrieve studies in diagnostic accuracy systematic reviews reported in ACP Journal Club in 2006. Twelve of 22 diagnostic accuracy reviews (452 included studies) met the inclusion criteria. After excluding 11 studies not in MEDLINE or EMBASE, 95% of articles (417 of 441) were captured by the sensitive Clinical Queries diagnosis search filter (MEDLINE and EMBASE combined). Of 24 studies not retrieved by the filter, 22 were not diagnostic accuracy studies. Reanalysis of the Clinical Queries filter without these 22 nondiagnosis articles increased its performance to 99% (417 of 419). We found no substantive impact of the two articles missed by the Clinical Queries filter on the conclusions of the systematic reviews in which they were cited. The sensitive Clinical Queries diagnostic search filter captured 99% of articles and 100% of substantive articles indexed in MEDLINE and EMBASE in diagnostic accuracy systematic reviews.

  17. Scrambled eggs: A highly sensitive molecular diagnostic workflow for Fasciola species specific detection from faecal samples

    Science.gov (United States)

    Calvani, Nichola Eliza Davies; Windsor, Peter Andrew; Bush, Russell David

    2017-01-01

    transport of samples from endemic to non-endemic countries without the requirement of a complete cold chain. The commercially-available ELISA displayed poorer sensitivity, even after adjustment of the positive threshold (65–88%), compared to the sensitivity (91–100%) of the new molecular diagnostic workflow. Conclusions/Significance Species-specific assays for sensitive detection of Fasciola spp. enable ante-mortem diagnosis in both human and animal settings. This includes Southeast Asia where there are potentially many undocumented human cases and where post-mortem examination of production animals can be difficult. The new molecular workflow provides a sensitive and quantitative diagnostic approach for the rapid testing of medium to large sample sizes, potentially superseding the traditional sedimentation and FEC technique and enabling surveillance programs in locations where animal and human health funding is limited. PMID:28915255

  18. Scrambled eggs: A highly sensitive molecular diagnostic workflow for Fasciola species specific detection from faecal samples.

    Science.gov (United States)

    Calvani, Nichola Eliza Davies; Windsor, Peter Andrew; Bush, Russell David; Šlapeta, Jan

    2017-09-01

    -endemic countries without the requirement of a complete cold chain. The commercially-available ELISA displayed poorer sensitivity, even after adjustment of the positive threshold (65-88%), compared to the sensitivity (91-100%) of the new molecular diagnostic workflow. Species-specific assays for sensitive detection of Fasciola spp. enable ante-mortem diagnosis in both human and animal settings. This includes Southeast Asia where there are potentially many undocumented human cases and where post-mortem examination of production animals can be difficult. The new molecular workflow provides a sensitive and quantitative diagnostic approach for the rapid testing of medium to large sample sizes, potentially superseding the traditional sedimentation and FEC technique and enabling surveillance programs in locations where animal and human health funding is limited.

  19. Scrambled eggs: A highly sensitive molecular diagnostic workflow for Fasciola species specific detection from faecal samples.

    Directory of Open Access Journals (Sweden)

    Nichola Eliza Davies Calvani

    2017-09-01

    to non-endemic countries without the requirement of a complete cold chain. The commercially-available ELISA displayed poorer sensitivity, even after adjustment of the positive threshold (65-88%, compared to the sensitivity (91-100% of the new molecular diagnostic workflow.Species-specific assays for sensitive detection of Fasciola spp. enable ante-mortem diagnosis in both human and animal settings. This includes Southeast Asia where there are potentially many undocumented human cases and where post-mortem examination of production animals can be difficult. The new molecular workflow provides a sensitive and quantitative diagnostic approach for the rapid testing of medium to large sample sizes, potentially superseding the traditional sedimentation and FEC technique and enabling surveillance programs in locations where animal and human health funding is limited.

  20. Quantifying the Accuracy of a Diagnostic Test or Marker

    NARCIS (Netherlands)

    Linnet, Kristian; Bossuyt, Patrick M. M.; Moons, Karel G. M.; Reitsma, Johannes B. R.

    2012-01-01

    BACKGROUND: In recent years, increasing focus has been directed to the methodology for evaluating (new) tests or biomarkers. A key step in the evaluation of a diagnostic test is the investigation into its accuracy. CONTENT: We reviewed the literature on how to assess the accuracy of diagnostic

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

    Science.gov (United States)

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

    2016-09-01

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

  2. Budgetary impact of diagnostic tests for visceral leishmaniasis in Brazil

    OpenAIRE

    Assis, Tália Santana Machado de; Azeredo-da-Silva, André Luís Ferreira de; Oliveira, Diana; Cota, Gláucia; Werneck, Guilherme Loureiro; Rabello, Ana

    2017-01-01

    Abstract: The aim of the present study was to estimate the financial costs of the incorporation and/or replacement of diagnostic tests for human visceral leishmaniasis (VL) in Brazil. The analysis was conducted from the perspective of the Brazilian Unified National Health System (SUS) over a period of three years. Six diagnostic tests were evaluated: the indirect immunofluorescence antibody test (IFAT), the IT LEISH rapid test, the parasitological examination of bone marrow aspirate, the dire...

  3. Recent Progress in the Development of Diagnostic Tests for Malaria

    Directory of Open Access Journals (Sweden)

    Francis D. Krampa

    2017-09-01

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

  4. Better Tests, Better Care: Improved Diagnostics for Infectious Diseases

    Science.gov (United States)

    Caliendo, Angela M.; Gilbert, David N.; Ginocchio, Christine C.; Hanson, Kimberly E.; May, Larissa; Quinn, Thomas C.; Tenover, Fred C.; Alland, David; Blaschke, Anne J.; Bonomo, Robert A.; Carroll, Karen C.; Ferraro, Mary Jane; Hirschhorn, Lisa R.; Joseph, W. Patrick; Karchmer, Tobi; MacIntyre, Ann T.; Reller, L. Barth; Jackson, Audrey F.

    2013-01-01

    In this IDSA policy paper, we review the current diagnostic landscape, including unmet needs and emerging technologies, and assess the challenges to the development and clinical integration of improved tests. To fulfill the promise of emerging diagnostics, IDSA presents recommendations that address a host of identified barriers. Achieving these goals will require the engagement and coordination of a number of stakeholders, including Congress, funding and regulatory bodies, public health agencies, the diagnostics industry, healthcare systems, professional societies, and individual clinicians. PMID:24200831

  5. Common Diagnostic Test Results Over the Years

    Directory of Open Access Journals (Sweden)

    Aruvee Eve

    2016-12-01

    Full Text Available In this article, common test results over the years 2000 – 2016 are analysed. The test questions for new entrants were based on secondary school mathematics. The students took the test in the first lesson of the higher mathematics course. The test results were analysed by years, by tasks and by specialities, and their differences were found. The test results’ dependence on state-exams score was studied and other types of dependence were looked at.

  6. Diagnostic performance of high-sensitive troponin T in patients with renal insufficiency.

    Science.gov (United States)

    Pfortmueller, Carmen A; Funk, Georg-Christian; Marti, Grischa; Leichtle, Alexander B; Fiedler, Georg M; Schwarz, Christoph; Exadaktylos, Aristomenis K; Lindner, Gregor

    2013-12-15

    In the present study, we wanted to (1) evaluate whether high-sensitive troponin T levels correlate with the grade of renal insufficiency and (2) test the accuracy of high-sensitive troponin T determination in patients with renal insufficiency for diagnosis of acute myocardial infarction (AMI). In this cross-sectional analysis, all patients who received serial measurements of high-sensitive troponin T from August 1, 2010, to October 31, 2012, at the Department of Emergency Medicine were included. We analyzed data on baseline characteristics, reason for referral, medication, cardiovascular risk factors, and outcome in terms of presence of AMI along with laboratory data (high-sensitive troponin T, creatinine). A total of 1,514 patients (67% male, aged 65 ± 16 years) were included, of which 382 patients (25%) had moderate to severe renal insufficiency and significantly higher levels of high-sensitive troponin T on admission (0.028 vs 0.009, p Renal Disease estimated glomerular filtration rate >60 ml/min presenting with acute chest pain or dyspnea and 0.535 (SE 0.056) for patients with moderate to severe renal insufficiency presenting with acute chest pain or dyspnea. In conclusion, the diagnostic accuracy for presence of AMI of a baseline measurement of high-sensitive troponin in patients with renal insufficiency was poor and resembles tossing a coin. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Parametric Sensitivity Tests- European PEM Fuel Cell Stack Test Procedures

    DEFF Research Database (Denmark)

    Araya, Samuel Simon; Andreasen, Søren Juhl; Kær, Søren Knudsen

    2014-01-01

    performed based on test procedures proposed by a European project, Stack-Test. The sensitivity of a Nafion-based low temperature PEMFC stack’s performance to parametric changes was the main objective of the tests. Four crucial parameters for fuel cell operation were chosen; relative humidity, temperature......, pressure, and stoichiometry at varying current density. Furthermore, procedures for polarization curve recording were also tested both in ascending and descending current directions....

  8. Diagnostic accuracy of temporomandibular disorder pain tests: a multicenter study

    NARCIS (Netherlands)

    Visscher, C.M.; Naeije, M.; de Laat, A.; Michelotti, A.; Nilner, M.; Craane, B.; Ekberg, E.; Farella, M.; Lobbezoo, F.

    2009-01-01

    AIMS: To estimate the diagnostic accuracy of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) clinical examination and of the dynamic/static tests for the recognition of TMD pain. Since the diagnosis of TMD pain is especially complicated in persistent orofacial pain

  9. Formaldehyde concentration in diagnostic patch testing

    DEFF Research Database (Denmark)

    Trattner, A; Johansen, J D; Menné, T

    1998-01-01

    Exposure to formaldehyde is common from both consumer products and industry. The reliability of the patch test is essential for the diagnosis of formaldehyde allergy as it is difficult to suspect from the patient's history. The recommended formaldehyde patch test concentration has been reduced over......% in consecutively patch-tested patients, with respect to frequency of positive patch test reactions, strength of patch test reactions to different formaldehyde test concentrations, irritancy and relevance. The study included 3734 consecutively patch tested patients. 121 gave a positive reaction to 1% and/or 2...... gave few additional positive cases compared to D 3/4. Problems related to relevance are discussed. Based on present knowledge, a 1% patch test concentration for formaldehyde is recommended....

  10. Impact sensitivity test of liquid energetic materials

    Science.gov (United States)

    Tiutiaev, A.; Dolzhikov, A.; Zvereva, I.

    2017-10-01

    This paper presents new experimental method for sensitivity evaluation at the impact. A large number of researches shown that the probability of explosion initiating of liquid explosives by impact depends on the chemical nature and the various external characteristics. But the sensitivity of liquid explosive in the presence of gas bubbles increases many times as compared with the liquid without gas bubbles. In this case local chemical reaction focus are formed as a result of compression and heating of the gas inside the bubbles. In the liquid as a result of convection, wave motion, shock, etc. gas bubbles are easily generated, it is necessary to develop methods for determining sensitivity of liquid explosives to impact and to research the explosives ignition with bubbles. For the experimental investigation, the well-known impact machine and the so-called appliance 1 were used. Instead of the metal cup in the standard method in this paper polyurethane foam cylindrical container with liquid explosive was used. Polyurethane foam cylindrical container is easily deforms by impact. A large number of tests with different liquid explosives were made. It was found that the test liquid explosive to impact in appliance 1 with polyurethane foam to a large extent reflect the real mechanical sensitivity due to the small loss of impact energy on the deformation of the metal cup, as well as the best differentiation liquid explosive sensitivity due to the higher resolution method.

  11. Personalized Medicine’s Bottleneck: Diagnostic Test Evidence and Reimbursement

    Directory of Open Access Journals (Sweden)

    Joshua P. Cohen

    2014-04-01

    Full Text Available Background: Personalized medicine is gradually emerging as a transformative field. Thus far, seven co-developed drug-diagnostic combinations have been approved and several dozen post-hoc drug-diagnostic combinations (diagnostic approved after the drug. However, barriers remain, particularly with respect to reimbursement. Purpose, methods: This study analyzes barriers facing uptake of drug-diagnostic combinations. We examine Medicare reimbursement in the U.S. of 10 drug-diagnostic combinations on the basis of a formulary review and a survey. Findings: We found that payers reimburse all 10 drugs, but with variable and relatively high patient co-insurance, as well as imposition of formulary restrictions. Payer reimbursement of companion diagnostics is limited and highly variable. In addition, we found that the body of evidence on the clinical- and cost-effectiveness of therapeutics is thin and even less robust for diagnostics. Conclusions, discussion: The high cost of personalized therapeutics and dearth of evidence concerning the comparative clinical effectiveness of drug-diagnostic combinations appear to contribute to high patient cost sharing, imposition of formulary restrictions, and limited and variable reimbursement of companion diagnostics. Our findings point to the need to increase the evidence base supportive of establishing linkage between diagnostic testing and positive health outcomes.

  12. [Multiple Myeloma - Current Status in Diagnostic Testing and Therapy].

    Science.gov (United States)

    Kehrer, Michael; Koob, Sebastian; Strauss, Andreas; Wirtz, Dieter Christian; Schmolders, Jan

    2017-10-01

    Background Multiple myeloma is a haematological blood cancer of the bone marrow and is classified by the World Health Organisation (WHO) as a plasma cell neoplasm. In multiple myeloma, normal plasma cells transform into malignant myeloma cells and produce large quantities of an abnormal immunoglobulin called monoclonal protein or M protein. This ultimately causes multiple myeloma symptoms such as bone damage or kidney problems. The annual worldwide incidence of multiple myeloma is estimated to be 6 - 7/100,000 and accounts for 1% of all cancer. In Germany, there are about 6,000 cases of newly diagnosed multiple myeloma per annum. In the current era of new agents, such as immunomodulatory drugs and proteasome inhibitors and antibodies, enormous progress has been achieved in the therapy of multiple myeloma. In orthopaedics, it is essential to be able to recognise the of alarming symptoms of multiple myeloma in clinical routine and to be aware of basic diagnostic features to confirm this disease. Surgical treatment of myeloma-related bone lesions - such as stabilisation of pathological fractures - is an important domain of tumour orthopaedic surgery. Methods A comprehensive literature search was performed in PubMed using the keywords "multiple myeloma" and "diagnostic" or "therapy". This served to evaluate the available primary and secondary literature on the current status of the diagnostic testing and therapy of multiple myeloma. Systematic reviews, meta-analyses and clinical studies as well as international recommendations in therapy were included until the spring of 2016. Results There are now very sensitive screening methods for the diagnosis of multiple myeloma. Accurate diagnosis is generally based on several factors, including physical evaluation, patient history, symptoms, and diagnostic testing results. The standards for initial diagnostic tests are determined by blood and urine tests as well as a bone marrow biopsy and skeletal imaging, such as X

  13. Diagnostic Accuracy of Lachman Test in the Evaluation of Anterior ...

    African Journals Online (AJOL)

    Background: In most cities and towns in the developing countries there are none or very few centers with sophisticated diagnostic investigative tests. We therefore depend a lot on clinical tests for diagnosis. The Lachman test is a very important test of the integrity of the anterior cruciate ligament. In this prospective study, the ...

  14. Emerging diagnostic tests for vitreoretinal lymphoma.

    Science.gov (United States)

    Dawson, Abby C; Williams, Keryn A; Appukuttan, Binoy; Smith, Justine R

    2018-04-19

    Vitreoretinal lymphoma, which most commonly is diffuse large B cell non-Hodgkin in type, is a rare cancer with high morbidity and high mortality. Making a tissue diagnosis of vitreoretinal lymphoma is a major challenge for clinicians due to biological and technical factors. Yet, the delay in start of treatment may have vision- and life- threatening consequences, and there is considerable interest in the application of molecular assays to improve the accuracy of the diagnostic process: detection of a clonal immunoglobulin heavy chain rearrangements in lymphoma cells by polymerase chain reaction; measurement of vitreous or aqueous interleukin-10 protein levels in ocular fluids; and identification of mutations in the myeloid differentiation primary response gene 88 in tumour cells. In this article, we review the historical development and current application of each of these molecular methods. We also discuss future opportunities for the molecular diagnosis of vitreoretinal lymphoma through next generation sequencing technologies. This article is protected by copyright. All rights reserved.

  15. Femoroacetabular cam-type impingement: Diagnostic sensitivity and specificity of radiographic views compared to radial MRI

    International Nuclear Information System (INIS)

    Domayer, S.E.; Ziebarth, K.; Chan, J.; Bixby, S.; Mamisch, T.C.; Kim, Y.J.

    2011-01-01

    Purpose: To retrospectively assess the diagnostic sensitivity of 45° Dunn view and cross-table lateral radiographs for the assessment of cam deformity by comparison with radial MRI. Materials and methods: 60 cases with radiographs (38 a–p and 45° Dunn views, 22 a–p and cross-table lateral views) and radial MRI were assessed. Alpha angle measurements were obtained both for radiographs and radial MRI. Statistics included frequency analysis, bivariate linear correlation analyses of MRI and radiograph measurements and cross-table analyses testing for the sensitivity and specificity of radiographs for the detection of an alpha angle larger than 55°. Results: 53.3% had the maximum alpha angle in the superior–anterior aspect of the femoral head–neck junction. Cam deformity was found in 45/60 cases (75%) in radial MRI. Pearson correlation demonstrated the Dunn view was most accurate for the superior–anterior aspect (.772, P < .001). The cross-table lateral views were best suited for the anterior–superior aspect (.511, P < .05). The sensitivity for cam deformity in the Dunn view was 96.4% vs. 70.6% in the cross-table lateral view. Conclusion: The 45° Dunn view can improve the first line of impingement diagnostics. Radial MRI however remains indispensable for pre-operative planning and the evaluation of symptomatic cases without obvious deformity.

  16. Learning Digital Test and Diagnostics via Internet

    Directory of Open Access Journals (Sweden)

    Heinz-Dietrich Wuttke

    2007-02-01

    Full Text Available An environment targeted to e-learning is presented for teaching design and test of electronic systems. The environment consists of a set of Java applets, and of web based access to the hardware equipments, which can be used in the classroom, for learning at home, in laboratory research and training, or for carrying out testing of students during exams. The tools support university courses on digital electronics, computer hardware, testing and design for testability to learn by hands-on exercises how to design digital systems, how to make them testable, how to build self-testing systems, how to generate test patterns, how to analyze the quality of tests, and how to localize faults in hardware. The tasks chosen for hands-on training represent simultaneously research problems, which allow to fostering in students critical thinking, problem solving skills and creativity.

  17. [Lymphocyte stimulation test, a possible alternative for verifying chloroacetophenone sensitization].

    Science.gov (United States)

    Brand, C U; Schmidli, J; Ballmer-Weber, B; Hunziker, T

    1995-10-01

    We report on a case of pronounced sensitization to chloroacetophenone tear gas that developed after repeated occupational skin exposure in a 57-year-old police officer. Mainly in the presence of moisture and occlusion, cutaneous application of chloroacetophenone leads to severe irritant, and often also allergic, skin reactions. In patch testing the demonstration of allergic contact dermatitis in response to chloroacetophenone is hampered by the irritative potential of this substance even at low concentrations. This diagnostic bias can be overcome by the lymphocyte proliferation assay.

  18. Optimizing adaptive learning through testing, diagnostic reflection and learner control

    NARCIS (Netherlands)

    Dirkx, Kim; Kester, Liesbeth; Kirschner, Paul A.

    2011-01-01

    Dirkx, K. J. H., Kester, L., & Kirschner, P. A. (2011, September). Optimizing adaptive learning through testing, diagnostic reflection and learner control. Presentation for visitors of KU Leuven, Open University, Heerlen, The Netherlands.

  19. Concordance in diagnostic testing for respiratory pathogens of Bighorn Sheep

    Science.gov (United States)

    Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack ...

  20. Diagnostic Accuracy of BRAF Immunohistochemistry in Colorectal Cancer: a Meta-Analysis and Diagnostic Test Accuracy Review.

    Science.gov (United States)

    Pyo, Jung-Soo; Sohn, Jin Hee; Kang, Guhyun

    2016-10-01

    The aim of this study was to evaluate the concordance between the BRAF (V600E) mutation test and immunohistochemistry (IHC) and to evaluate the diagnostic accuracy of BRAF IHC for colorectal cancer (CRC) through a systematic review, meta-analysis, and diagnostic test accuracy review. The current study included 1021 CRCs from eight eligible studies. The concordance rates were investigated between BRAF IHC and the mutation test. In addition, diagnostic test accuracy review was conducted and calculated using the value of area under curve (AUC) on the summary receiver operating characteristic (SROC) curve. The positive rate of BRAF IHC was 30.5 % (range; 13.2-66.2 %), and the BRAF mutation was found in 30.2 % (range; 11.7-66.2 %). The overall concordance rate between BRAF IHC and the mutation test was 0.944 (95 % confidence interval (CI) 0.873-0.977). In the BRAF IHC-positive and -negative groups, the concordance rates between BRAF IHC and the mutation test were 0.895 (95 % CI 0.800-0.945) and 0.956 (95 % CI 0.878-0.985), respectively. The pooled sensitivity and specificity were 0.94 (95 % CI 0.91-0.96) and 0.96 (95 % CI 0.95-0.98), respectively. The diagnostic odds ratio was 272.86 (95 % CI 46.11-1614.88), and the value of AUC on SROC curve was 0.9846. Taken together, our results suggest that BRAF IHC is strongly concordant with the BRAF mutation test and has high diagnostic accuracy in BRAF mutation analysis of CRCs. Further cumulative studies on detailed evaluation criteria are needed before application in daily practice.

  1. UREA BREATH TEST – ITS ROLE IN DIAGNOSTICS

    Directory of Open Access Journals (Sweden)

    Joško Osredkar

    2004-01-01

    Full Text Available Background. Each year many patients visit their physicians complaining of digestive symptoms, most commonly functional dyspepsia (»indigestion« or gastroesophageal reflux (»heartburn«. However, many patients with abdominal discomfort are actually suffering from gastric or duodenal ulcers that are commonly caused by H. pylori and thus are curable. Clearing the infection usually heals the ulcer and prevents relapse, so an accurate diagnosis is important. There are several options for diagnosing H. pylori infection: serology to detect antibodies against the bacterium; endoscopic biopsy for urease testing (H. pylori produce a urease that breaks down urea to ammonia and carbon dioxide; histology with special stains; or culture. Unfortunately, these procedures are invasive, expensive and not always accurate. Serological tests require a blood sample and tell only that a patient has been exposed to H. pylori at some time in the past, but not whether the patient is currently infected. Endoscopy and biopsy can detect current infection — the CLO test urease test allows rapid detection of H. pylori in gastric biopsy specimens — but endoscopy and biopsy are unpleasant medical procedures.Recently, noninvasive, sensitive, specific, easy to perform and patient’s well accepted methods had been developed known as urea breath test (UBT. When an infected person swallows a dose of urea labeled with an isotope of carbon — carbon-13 (13C or carbon-14 (14C – H. pylori in the gastric mucosa break down the labeled urea to form ammonia and labeled carbon dioxide. The carbon dioxide is absorbed into the bloodstream and excreted via the lungs. The patient then exhales into a device that measures the level of carbon dioxide. The urea breath test is specific for H. pylori (it detects only urease-producing bacteria, it is sensitive (the labeled urea reaches a large area of the stomach and thus reflects total gastric urease activity and the results can be

  2. Diagnostic Bias and Conduct Disorder: Improving Culturally Sensitive Diagnosis

    Science.gov (United States)

    Mizock, Lauren; Harkins, Debra

    2011-01-01

    Disproportionately high rates of Conduct Disorder are diagnosed in African American and Latino youth of color. Diagnostic bias contributes to overdiagnosis of Conduct Disorder in these adolescents of color. Following a diagnosis of Conduct Disorder, adolescents of color face poorer outcomes than their White counterparts. These negative outcomes…

  3. Role of diagnostic tests in esophageal evaluation

    International Nuclear Information System (INIS)

    Silverstein, B.D.; Pope, C.E. II

    1980-01-01

    In the evaluation of esophageal disease, the appropriate question must be asked before the correct tests can be selected. Reflux can be demonstrated by radiologic methods, pH testing or radioisotopic techniques. Esophageal mucosal damage is best evaluated by x-ray, endoscopy, or biopsy. Chest pain is demonstrated by acid infusion or by manometry. Two algorithms are presented for the evaluation of chest pain and reflux symptoms

  4. Diagnostic testing managed by hematopathology specialty and other laboratories: costs and patient diagnostic outcomes.

    Science.gov (United States)

    Engel-Nitz, Nicole M; Eckert, Benjamin; Song, Rui; Koka, Priyanka; Hulbert, Erin M; McPheeters, Jeffrey; Teitelbaum, April

    2014-01-01

    Successful management of patients with hematologic malignancies depends upon accurate and timely diagnosis, which frequently requires integration and interpretation of multiple tests. Our retrospective analysis compared diagnostic uncertainty, resource utilization, and costs for patients with diagnostic bone marrow (BM) tests managed by commercial laboratories. Patients with BM biopsies and suspected hematologic cancer/condition were identified from claims (2005-2011) within a large US health plan (coverage ≥6 pre- and ≥3-months post-biopsy). Cohorts defined by laboratories performing BM morphologic assessment/directing testing sequence: Genoptix (GX, specialty hematology-testing laboratory), large commercial laboratories (LL), other laboratories (OL). One-year post-biopsy changes in diagnosis or treatments, tests performed, and diagnostic/treatment medical costs (measured as per-patient-per-month [PPPM]) were examined. The study population included 1,387 GX, 4,162 LL, and 19,115 OL patients with suspected hematologic malignancy/disease and BM morphology assessment. GX had lower diagnostic uncertainty measured between 2 time periods by diagnostic stability (no conditions the same; 6.16% GX, 8.04% LL, 9.73% OL; p laboratory may result in earlier final diagnosis, fewer subsequent diagnosis changes, reduced need for follow-on testing requiring repeat biopsy procedures, and may result in lower downstream healthcare costs. Further evaluations using medical chart abstractions or registries will be valuable.

  5. Diagnostic relevance of IgE sensitization profiles to eight recombinant Phleum pratense molecules.

    Science.gov (United States)

    Cipriani, F; Mastrorilli, C; Tripodi, S; Ricci, G; Perna, S; Panetta, V; Asero, R; Dondi, A; Bianchi, A; Maiello, N; Miraglia Del Giudice, M; Frediani, T; Macrì, F; Lucarelli, S; Dello Iacono, I; Patria, M F; Varin, E; Peroni, D; Chini, L; Moschese, V; Bernardini, R; Pingitore, G; Pelosi, U; Tosca, M; Paravati, F; Sfika, I; Businco, A Di Rienzo; Povesi Dascola, C; Comberiati, P; Frediani, S; Lambiase, C; Verga, M C; Faggian, D; Plebani, M; Calvani, M; Caffarelli, C; Matricardi, P M

    2018-03-01

    Grass pollen-related seasonal allergic rhinoconjunctivitis (SARg) is clinically heterogeneous in severity, comorbidities, and response to treatment. The component-resolved diagnostics disclosed also a high heterogeneity at molecular level. Our study aimed at analyzing the characteristics of the IgE sensitization to Phleum pratense molecules and investigating the diagnostic relevance of such molecules in childhood. We examined 1120 children (age 4-18 years) with SARg. Standardized questionnaires on atopy were acquired through informatics platform (AllergyCARD™). Skin prick tests were performed with pollen extracts. Serum IgE to airborne allergens and eight P. pratense molecules (rPhl p 1, rPhl p 2, rPhl p 4, rPhl p 5b, rPhl p 6, rPhl p 7, rPhl p 11, rPhl p 12) were tested by ImmunoCAP FEIA. The analysis of IgE responses against eight P. pratense molecules showed 87 profiles. According to the number of molecules recognized by IgE, the more complex profiles were characterized by higher serum total IgE, higher grass-specific serum IgE, and higher number and degree of sensitization to pollens. The most frequent IgE sensitization profile was the monomolecular Phl p 1. Sensitization to Phl p 7 was a reliable biomarker of asthma, whereas Phl p 12 of oral allergy syndrome. Sensitization to Phl p 7 was associated with a higher severity of SARg, and complex profiles were associated with longer disease duration. In a large pediatric population, the complexity of IgE sensitization profiles against P. pratense molecules is related to high atopic features although useless for predicting the clinical severity. The detection of serum IgE to Phl p 1, Phl p 7, and Phl p 12 can be used as clinical biomarkers of SARg and comorbidities. Further studies in different areas are required to test the impact of different IgE molecular profiles on AIT response. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  6. QUANTITATIVE BUFFY COAT (QBC) TEST AND OTHER DIAGNOSTIC TECHNIQUES FOR DIAGNOSIG MALARIA: REVIEW OF LITRATURE

    OpenAIRE

    Kuladeepa Ananda Vaidya; Sukesh K

    2012-01-01

    The technical capability to perform a correct and timely diagnosis of malaria infection in an ill patient is of critical importance since symptoms of complicated malaria may suddenly develop, leading to death of the patient. Even though peripheral blood smear examination is considered as the gold standard technique, tests like Quantitative Buffy Coat (QBC) test and Rapid diagnostic tests (RDTs) are widely used and more sensitive in detecting malaria parasite. Here we are briefly highlighting ...

  7. High sensitivity point-of-care device for direct virus diagnostics

    DEFF Research Database (Denmark)

    Kiilerich-Pedersen, Katrine; Dapra, Johannes; Cherré, Solène

    2013-01-01

    Influenza infections are associated with high morbidity and mortality, carry the risk of pandemics, and pose a considerable economic burden worldwide. To improve the management of the illness, it is essential with accurate and fast point-of-care diagnostic tools for use in the field or at the pat......Influenza infections are associated with high morbidity and mortality, carry the risk of pandemics, and pose a considerable economic burden worldwide. To improve the management of the illness, it is essential with accurate and fast point-of-care diagnostic tools for use in the field...... or at the patient's bedside. Conventional diagnostic methods are time consuming, expensive and require specialized laboratory facilities. We present a highly sensitive, highly specific, and low cost platform to test for acute virus infections in less than 15. min, employing influenza A virus (H1N1) as an example...... of its usability. An all polymer microfluidic system with a functionalized conductive polymer (PEDOT-OH:TsO) microelectrode array was developed and exploited for label free and real time electrochemical detection of intact influenza A virus (H1N1) particles. DNA aptamers with affinity for influenza...

  8. Understanding the medical and nonmedical value of diagnostic testing.

    Science.gov (United States)

    Lee, David W; Neumann, Peter J; Rizzo, John A

    2010-01-01

    To develop a framework for defining the potential value of diagnostic testing, and discuss its implications for the health-care delivery system. We reviewed the conceptual and empirical literature related to the valuing of diagnostic tests, and used this information to create a framework for characterizing their value. We then made inferences about the impact of this framework on health insurance coverage, health technology assessment, physician-patient relationships, and public health policy. Three dimensions can effectively classify the potential value created by diagnostic tests: 1) medical value (impact on treatment decisions); 2) planning value (affect on patients' ability to make better life decisions); and 3) psychic value (how test information affects patients' sense of self). This comprehensive framework for valuing diagnostics suggests that existing health technology assessments may systematically under- or overvalue diagnostics, leading to potentially incorrect conclusions about cost-effectiveness. Further, failure to account for all value dimensions may lead to distorted payments under a value-based health-care system. The potential value created by medical diagnostics incorporates medical value as well as value associated with well-being and planning. Consideration of all three dimensions has important implications for technology assessment and value-based payment.

  9. A Diagnostic Test for Apraxia in Stroke Patients : Internal consistency and diagnostic value

    NARCIS (Netherlands)

    van Heugten, C.M.; Dekker, J.; Deelman, B.G.; Stehmann-Saris, J.C; Kinebanian, A

    The internal consistency and the diagnostic value of a test for apraxia in patients having had a stroke are presented. Results indicate that the items of the test form a strong and consistent scale: Cronbach's alpha as well as the results of a Mokken scale analysis present good reliability and good

  10. A diagnostic test for apraxia in stroke patients: internal consistency and diagnostic value.

    NARCIS (Netherlands)

    Heugten, C.M. van; Dekker, J.; Deelman, B.G.; Stehmann-Saris, F.C.; Kinebanian, A.

    1999-01-01

    The internal consistency and the diagnostic value of a test for apraxia in patients having had a stroke are presented. Results indicate that the items of the test form a strong and consistent scale: Cronbach's alpha as well as the results of a Mokken scale analysis present good reliability and good

  11. Diagnostic tests in obstetrics: a method for improved evaluation.

    Science.gov (United States)

    Richardson, D K; Schwartz, J S; Weinbaum, P J; Gabbe, S G

    1985-07-15

    With the proliferation of diagnostic tests in obstetrics, several recurrent questions arise. How does one determine whether one diagnostic test is superior to another available test? What test cutoff value best separates diseased from nondiseased patients? How much does performance of additional tests assist in arriving at a correct diagnosis? This article reviews a simple yet sophisticated analytic technique, the receiver operating characteristic curve, and demonstrates its application to several obstetric diagnostic tests. Receiver operating characteristic curve analysis is used to select a cutoff value for the 1-hour glucose tolerance test, to compare amniotic fluid tests of fetal lung maturity, and to determine the optimal combinations of factors and overall performance of the fetal biophysical profile. The value of receiver operating characteristic curve analysis lies in providing a clear graphic analysis of the performance of diagnostic tests over their entire range of values. It also provides the starting point for evaluating the costs and benefits of alternative cutoff points in differing clinical settings.

  12. Diagnostic sensitivity and specificity of Doppler ultrasound in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Terslev, L.; Recke, P. von der; Torp-Pedersen, S.

    2008-01-01

    Objective. To evaluate the sensitivity and specificity of Doppler ultrasound (DUS) in diagnosing arthritis in the wrist and hands, and, if possible, to define a cutoff level for our ultrasound measures for inflammation, resistive index (RI), and color fraction. Methods. Using DUS, 88 patients...

  13. SPS Dipole Multipactor Test and TEWave Diagnostics

    CERN Document Server

    Caspers, F; Edwards, P; Federmann, S; Holz, M; Taborelli, M

    2013-01-01

    Electron cloud accumulation in particle accelerators can be mitigated by coating the vacuum beam pipe with thin films of low secondary electron yield (SEY) material. The SEY of small coated samples are usually measured in the laboratory. To further test the properties of different coating materials, RF-induced multipacting in a coaxial waveguide configuration can be performed. The technique is applied to two main bending dipoles of the SPS, where the RF power is fed through a tungsten wire stretched along the vacuum chamber (6.4 m). A dipole with a bare stainless steel chamber shows a clear power threshold initiating an abrupt rise in reflected power and pressure. The effect is enhanced at RF frequencies corresponding to electron cyclotron resonances for given magnetic fields. Preliminary results show that the dipole with a carbon coated vacuum chamber does not exhibit any pressure rise or reflected RF power up to the maximum available input power. In the case of a large scale coating production this techniqu...

  14. Nonparametric predictive inference for combining diagnostic tests with parametric copula

    Science.gov (United States)

    Muhammad, Noryanti; Coolen, F. P. A.; Coolen-Maturi, T.

    2017-09-01

    Measuring the accuracy of diagnostic tests is crucial in many application areas including medicine and health care. The Receiver Operating Characteristic (ROC) curve is a popular statistical tool for describing the performance of diagnostic tests. The area under the ROC curve (AUC) is often used as a measure of the overall performance of the diagnostic test. In this paper, we interest in developing strategies for combining test results in order to increase the diagnostic accuracy. We introduce nonparametric predictive inference (NPI) for combining two diagnostic test results with considering dependence structure using parametric copula. NPI is a frequentist statistical framework for inference on a future observation based on past data observations. NPI uses lower and upper probabilities to quantify uncertainty and is based on only a few modelling assumptions. While copula is a well-known statistical concept for modelling dependence of random variables. A copula is a joint distribution function whose marginals are all uniformly distributed and it can be used to model the dependence separately from the marginal distributions. In this research, we estimate the copula density using a parametric method which is maximum likelihood estimator (MLE). We investigate the performance of this proposed method via data sets from the literature and discuss results to show how our method performs for different family of copulas. Finally, we briefly outline related challenges and opportunities for future research.

  15. 76 FR 39110 - Medicare Program; Section 3113: The Treatment of Certain Complex Diagnostic Laboratory Tests...

    Science.gov (United States)

    2011-07-05

    ... Certain Complex Diagnostic Laboratory Tests Demonstration AGENCY: Centers for Medicare & Medicaid Services... participate in the Treatment of Certain Complex Diagnostic Laboratory Tests Demonstration. The Demonstration... complex diagnostic laboratory test under the Demonstration. The statute requires a Report to Congress that...

  16. 76 FR 49491 - Medicare Program; Section 3113: The Treatment of Certain Complex Diagnostic Laboratory Tests...

    Science.gov (United States)

    2011-08-10

    ... Certain Complex Diagnostic Laboratory Tests Demonstration; Extension of the Deadline for Submission of... Complex Diagnostic Laboratory Tests Demonstration. The deadline for submitting supporting information to... Treatment of Certain Complex Diagnostic Laboratory Tests Demonstration. The Demonstration is mandated by...

  17. A comparison of rapid diagnostic testing (by plasmodium lactate ...

    African Journals Online (AJOL)

    Background: The World Health Organization (WHO) considers early and rapid diagnosis as one of the strategies to control malaria. This study compared the performance of Quantitative Buffy Coat (QBC) test and the Plasmodium lactate dehydrogenase (pLDH) rapid diagnostic test (RDT) with microscopy as the gold ...

  18. Outcome of Presumptive Versus Rapid Diagnostic Tests-Based ...

    African Journals Online (AJOL)

    First, 50 children with malaria-pneumonia symptom overlap were consecutively enrolled and treated presumptively with antibiotics and antimalarials irrespective of malaria test result (control arm).Then, another 50 eligible children were enrolled and treated with antibiotics with/out antimalarials based on rapid diagnostic test ...

  19. Diagnostic, carrier and prenatal genetic testing for fragile X ...

    African Journals Online (AJOL)

    tremor/ataxia syndrome (FXTAS) and FMR-1-related primary ovarian insufficiency (POI) – at the Division of Human Genetics,. Johannesburg, for diagnostic, carrier and prenatal genetic testing. Methods. The records of 2 690 patients with ID and suspected FXS (ID/?FXS) who had genetic testing for FMR-1 between 1992 and ...

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

    Science.gov (United States)

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

    2013-09-01

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

  1. A systematic review of the diagnostic performance of orthopedic physical examination tests of the hip

    Science.gov (United States)

    2013-01-01

    Background Previous reviews of the diagnostic performances of physical tests of the hip in orthopedics have drawn limited conclusions because of the low to moderate quality of primary studies published in the literature. This systematic review aims to build on these reviews by assessing a broad range of hip pathologies, and employing a more selective approach to the inclusion of studies in order to accurately gauge diagnostic performance for the purposes of making recommendations for clinical practice and future research. It specifically identifies tests which demonstrate strong and moderate diagnostic performance. Methods A systematic search of Medline, Embase, Embase Classic and CINAHL was conducted to identify studies of hip tests. Our selection criteria included an analysis of internal and external validity. We reported diagnostic performance in terms of sensitivity, specificity, predictive values and likelihood ratios. Likelihood ratios were used to identify tests with strong and moderate diagnostic utility. Results Only a small proportion of tests reported in the literature have been assessed in methodologically valid primary studies. 16 studies were included in our review, producing 56 independent test-pathology combinations. Two tests demonstrated strong clinical utility, the patellar-pubic percussion test for excluding radiologically occult hip fractures (negative LR 0.05, 95% Confidence Interval [CI] 0.03-0.08) and the hip abduction sign for diagnosing sarcoglycanopathies in patients with known muscular dystrophies (positive LR 34.29, 95% CI 10.97-122.30). Fifteen tests demonstrated moderate diagnostic utility for diagnosing and/or excluding hip fractures, symptomatic osteoarthritis and loosening of components post-total hip arthroplasty. Conclusions We have identified a number of tests demonstrating strong and moderate diagnostic performance. These findings must be viewed with caution as there are concerns over the methodological quality of the primary

  2. A Novel Field Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis

    Science.gov (United States)

    2015-10-01

    equivalent of ᝺ parasites in spiked clinical specimens. We will compare the analytical sensitivity and specificity of RPA-LF with qPCR using a broad panel of...AWARD NUMBER: W81XWH-14-2-0196 TITLE: A Novel Field-Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis PRINCIPAL INVESTIGATOR... Diagnostic Test for Cutaneous Leishmaniasis 5b. GRANT NUMBER W81XWH-14-2-0196 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER LT Robert

  3. Irregular analytical errors in diagnostic testing - a novel concept.

    Science.gov (United States)

    Vogeser, Michael; Seger, Christoph

    2018-02-23

    In laboratory medicine, routine periodic analyses for internal and external quality control measurements interpreted by statistical methods are mandatory for batch clearance. Data analysis of these process-oriented measurements allows for insight into random analytical variation and systematic calibration bias over time. However, in such a setting, any individual sample is not under individual quality control. The quality control measurements act only at the batch level. Quantitative or qualitative data derived for many effects and interferences associated with an individual diagnostic sample can compromise any analyte. It is obvious that a process for a quality-control-sample-based approach of quality assurance is not sensitive to such errors. To address the potential causes and nature of such analytical interference in individual samples more systematically, we suggest the introduction of a new term called the irregular (individual) analytical error. Practically, this term can be applied in any analytical assay that is traceable to a reference measurement system. For an individual sample an irregular analytical error is defined as an inaccuracy (which is the deviation from a reference measurement procedure result) of a test result that is so high it cannot be explained by measurement uncertainty of the utilized routine assay operating within the accepted limitations of the associated process quality control measurements. The deviation can be defined as the linear combination of the process measurement uncertainty and the method bias for the reference measurement system. Such errors should be coined irregular analytical errors of the individual sample. The measurement result is compromised either by an irregular effect associated with the individual composition (matrix) of the sample or an individual single sample associated processing error in the analytical process. Currently, the availability of reference measurement procedures is still highly limited, but LC

  4. Diagnostic PCR: Comparative sensitivity of four probe chemistries

    DEFF Research Database (Denmark)

    Josefsen, Mathilde Hartmann; Löfström, Charlotta; Sommer, Helle Mølgaard

    2009-01-01

    Three probe chemistries: locked nucleic acid (LNA), minor groove binder (MGB) and Scorpion were compared with a TaqMan probe in a validated real-time PCR assay for detection of food-borne thermotolerant Campylobacter. The LNA probe produced significantly lower Ct-values and a higher proportion...... of positive PCR responses analyzing less than 150 DNA copies than the TaqMan probe. Choice of probe chemistry clearly has an impact on the sensitivity of PCR assays, and should be considered in an optimization strategy....

  5. Mixed Portmanteau Test for Diagnostic Checking of Time Series Models

    Directory of Open Access Journals (Sweden)

    Sohail Chand

    2014-01-01

    Full Text Available Model criticism is an important stage of model building and thus goodness of fit tests provides a set of tools for diagnostic checking of the fitted model. Several tests are suggested in literature for diagnostic checking. These tests use autocorrelation or partial autocorrelation in the residuals to criticize the adequacy of fitted model. The main idea underlying these portmanteau tests is to identify if there is any dependence structure which is yet unexplained by the fitted model. In this paper, we suggest mixed portmanteau tests based on autocorrelation and partial autocorrelation functions of the residuals. We derived the asymptotic distribution of the mixture test and studied its size and power using Monte Carlo simulations.

  6. Sensitivity and Specificity of the Phallometric Test for Hebephilia.

    Science.gov (United States)

    Cantor, James M; McPhail, Ian V

    2015-09-01

    The phallometric test has been examined most widely in the literature with regard to its ability to detect pedophilia; however, it has become of increasing interest to clinicians and researchers to ascertain to what extent the test accurately detects hebephilia: Whereas pedophilia refers to an adult's sexual interest in prepubescent children (age 10 or younger, on average), hebephilia refers to an adult's sexual interest in pubescent children (ages 11-14, on average). The aim of this study was to estimate the accuracy of volumetric phallometry in distinguishing pedophilic men and hebephilic men from men who are teleiophilic (primarily sexually interested in adults, age 17 or older). A retrospective chart review was conducted on the cumulate database of a large phallometric laboratory and clinic to identify a group of 239 men who committed sexual offenses against extrafamilial adults age 17 or older and a group of 996 men who committed sexual offenses against extrafamilial children age 14 or younger, all of whom professed a greater sexual interest in adults over children. The sensitivity and specificity of the phallometric test is calculated for its accuracy in distinguishing sexual preferences for children spanning various age ranges. Receiver operator characteristic curves were highly significant for each classification decision: Using its previously established cut-point of +0.25 standard deviation (SD) units, the phallometric test detected hebephilia with a sensitivity and specificity of 70.0% and 90.7%, detected pedophilia with 46.9% and 100%, and detected pedohebephilia with 75.3% and 90.7%. At a new cut-point of +0.0 SD units, the sensitivity and specificity of the test for pedophilia was 71.9% and 95.3%. Volumetric phallometry significantly distinguishes teleiophilic sex offenders from each of pedophilic, hebephilic, and pedohebephilic sex offenders and can serve as a reliable diagnostic test of sexual age preference among men who deny sexual interest in

  7. Convergent and diagnostic validity of STAVUX, a word and pseudoword spelling test for adults.

    Science.gov (United States)

    Östberg, Per; Backlund, Charlotte; Lindström, Emma

    2016-10-01

    Few comprehensive spelling tests are available in Swedish, and none have been validated in adults with reading and writing disorders. The recently developed STAVUX test includes word and pseudoword spelling subtests with high internal consistency and adult norms stratified by education. This study evaluated the convergent and diagnostic validity of STAVUX in adults with dyslexia. Forty-six adults, 23 with dyslexia and 23 controls, took STAVUX together with a standard word-decoding test and a self-rated measure of spelling skills. STAVUX subtest scores showed moderate to strong correlations with word-decoding scores and predicted self-rated spelling skills. Word and pseudoword subtest scores both predicted dyslexia status. Receiver-operating characteristic (ROC) analysis showed excellent diagnostic discriminability. Sensitivity was 91% and specificity 96%. In conclusion, the results of this study support the convergent and diagnostic validity of STAVUX.

  8. Background review for diagnostic test development for Zika virus infection.

    Science.gov (United States)

    Charrel, Rémi N; Leparc-Goffart, Isabelle; Pas, Suzan; de Lamballerie, Xavier; Koopmans, Marion; Reusken, Chantal

    2016-08-01

    To review the state of knowledge about diagnostic testing for Zika virus infection and identify areas of research needed to address the current gaps in knowledge. We made a non-systematic review of the published literature about Zika virus and supplemented this with information from commercial diagnostic test kits and personal communications with researchers in European preparedness networks. The review covered current knowledge about the geographical spread, pathogen characteristics, life cycle and infection kinetics of the virus. The available molecular and serological tests and biosafety issues are described and discussed in the context of the current outbreak strain. We identified the following areas of research to address current knowledge gaps: (i) an urgent assessment of the laboratory capacity and capability of countries to detect Zika virus; (ii) rapid and extensive field validation of the available molecular and serological tests in areas with and without Zika virus transmission, with a focus on pregnant women; (iii) monitoring the genomic diversity of circulating Zika virus strains; (iv) prospective studies into the virus infection kinetics, focusing on diagnostic sampling (specimen types, combinations and timings); and (v) developing external quality assessments for molecular and serological testing, including differential diagnosis for similar viruses and symptom clusters. The availability of reagents for diagnostic development (virus strains and antigens, quantified viral ribonucleic acid) needs to be facilitated. An international laboratory response is needed, including preparation of protocols for prospective studies to address the most pressing information needs.

  9. Beyond the 2×2 -contingency table: a primer on entropies and mutual information in various scenarios involving m diagnostic categories and n categories of diagnostic tests.

    Science.gov (United States)

    Reibnegger, Gilbert

    2013-10-21

    Usual evaluation tools for diagnostic tests such as, sensitivity/specificity and ROC analyses, are designed for the discrimination between two diagnostic categories, using dichotomous test results. Information theoretical quantities such as mutual information allow in depth-analysis of more complex discrimination problems, including continuous test results, but are rarely used in clinical chemistry. This paper provides a primer on useful information theoretical concepts with a strong focus on typical diagnostic scenarios. Information theoretical concepts are shortly explained. Mathematica CDF documents are provided which compute entropies and mutual information as function of pretest probabilities and the distribution of test results among the categories, and allow interactive exploration of the behavior of these quantities in comparison with more conventional diagnostic measures. Using data from a previously published study, the application of information theory to practical diagnostic problems involving up to 4×4 -contingency tables is demonstrated. Information theoretical concepts are particularly useful for diagnostic problems requiring more than the usual binary classification. Quantitative test results can be properly analyzed, and in contrast to popular concepts such as ROC analysis, the effects of variations of pre-test probabilities of the diagnostic categories can be explicitly taken into account. © 2013 Elsevier B.V. All rights reserved.

  10. The diagnostic accuracy of three rapid diagnostic tests for typhoid fever at Chittagong Medical College Hospital, Chittagong, Bangladesh.

    Science.gov (United States)

    Maude, Rapeephan R; de Jong, Hanna K; Wijedoru, Lalith; Fukushima, Masako; Ghose, Aniruddha; Samad, Rasheda; Hossain, Mohammed Amir; Karim, Mohammed Rezaul; Faiz, Mohammed Abul; Parry, Christopher M

    2015-10-01

    To determine the diagnostic accuracy of three rapid diagnostic tests (RDTs) for typhoid fever in febrile hospitalised patients in Bangladesh. Febrile adults and children admitted to Chittagong Medical College Hospital, Bangladesh, were investigated with Bact/Alert(®) blood cultures and real-time PCR to detect Salmonella enterica Typhi and Paratyphi A and assays for Rickettsia, leptospirosis and dengue fever. Acute serum samples were examined with the LifeAssay (LA) Test-it™ Typhoid IgM lateral flow assay detecting IgM antibodies against S. Typhi O antigen, CTKBiotech Onsite Typhoid IgG/IgM Combo Rapid-test cassette lateral flow assay detecting IgG and IgM antibodies against S. Typhi O and H antigens and SD Bioline line assay for IgG and IgM antibodies against S. Typhi proteins. In 300 malaria smear-negative febrile patients [median (IQR) age of 13.5 (5-31) years], 34 (11.3%) had confirmed typhoid fever: 19 positive by blood culture for S. Typhi (three blood PCR positive) and 15 blood culture negative but PCR positive for S. Typhi in blood. The respective sensitivity and specificity of the three RDTs in patients using a composite reference standard of blood culture and/or PCR-confirmed typhoid fever were 59% and 61% for LifeAssay, 59% and 74% for the CTK IgM and/or IgG, and 24% and 96% for the SD Bioline RDT IgM and/or IgG. The LifeAssay RDT had a sensitivity of 63% and a specificity of 91% when modified with a positive cut-off of ≥2+ and analysed using a Bayesian latent class model. These typhoid RDTs demonstrated moderate diagnostic accuracies, and better tests are needed. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

  11. 42 CFR 410.33 - Independent diagnostic testing facility.

    Science.gov (United States)

    2010-10-01

    ... business hours. (15) With the exception of hospital-based and mobile IDTFs, a fixed-base IDTF is prohibited... facility (IDTF). An IDTF may be a fixed location, a mobile entity, or an individual nonphysician... Drug Administration. (ii) Diagnostic tests personally furnished by a qualified audiologist as defined...

  12. Exploring sources of heterogeneity in systematic reviews of diagnostic tests

    NARCIS (Netherlands)

    Lijmer, Jeroen G.; Bossuyt, Patrick M. M.; Heisterkamp, Siem H.

    2002-01-01

    It is indispensable for any meta-analysis that potential sources of heterogeneity are examined, before one considers pooling the results of primary studies into summary estimates with enhanced precision. In reviews of studies on the diagnostic accuracy of tests, variability beyond chance can be

  13. The role of neuro-electrophysiological diagnostic tests in clinical ...

    African Journals Online (AJOL)

    Objective: To summarise and discuss the role of neuro-electrophysiological diagnostic tests in clinical medicine. Data Sources: Published original research and reviews to date. Study Selection: The review was with emphasis on diagnosis of peripheral neuropathic and neuromuscular disorders. Data extraction and ...

  14. Assessment of the Diagnostic Potential of Clinotech TB Screen Test ...

    African Journals Online (AJOL)

    The Clinotech TB Screen test, a 3rd generation multi-antigen rapid chromatographic immunoassay for detection of IgG antibodies in serum against recombinant protein antigens 38kDa, 16kDa and 6kDa, was assessed for its diagnostic potential for diagnosis of active pulmonary TB in routine TB control programme in Abia ...

  15. Classification of chronic orofacial pain using an intravenous diagnostic test

    NARCIS (Netherlands)

    Tjakkes, G. -H. E.; De Bont, L. G. M.; van Wijhe, M.; Stegenga, B.

    The aim of this study was to evaluate the ability of a preliminary intravenous diagnostic test to classify chronic orofacial pain patients into different subgroups. Patients with chronic orofacial pain conditions that could not be unambiguously diagnosed. A retrospective evaluation of series of

  16. Field evaluation of a malaria rapid diagnostic test (ICT Pf ...

    African Journals Online (AJOL)

    Background. Malaria rapid diagnostic tests (MRDTs) are quick and easy to perform and useful for diagnosing malaria in primary health care settings. In South Africa most malaria infections are due to Plasmodium falciparum, and HRPII-based MRDTs have been used since 2001. Previous studies in Africa showed variability ...

  17. Evaluation of microscopy and rapid diagnostic tests in screening ...

    African Journals Online (AJOL)

    Malaria is a life-threatening disease caused by the protozoa of the genus Plasmodium. Infection of individual is through the bites of infected female Anopheles mosquitoes. This study evaluated the performance of microscopy and rapid diagnostic tests (RDTs) in diagnosing malaria. A total of 400 clinically suspected malaria ...

  18. An audit of diagnostic tests performed in medical microbiology, and ...

    African Journals Online (AJOL)

    Clinical audit is an important tool for reviewing and improving the quality of service in clinical laboratories. This is a three year audit of diagnostic test carried out in Medical Microbiology and Immunology laboratories of University of Maiduguri Teaching Hospital, Maiduguri, Nigeria. The objectives were to document and ...

  19. Comparative analysis of two rapid diagnostic tests for diagnosis of ...

    African Journals Online (AJOL)

    This study aims at comparing the diagnostic efficiencies of two commercially available kits for detecting Plasmodium falciparum infection in urine and blood of febrile patients for malaria diagnosis. This was an observational study in which matched blood and urine from symptomatic patients were tested for malaria using two ...

  20. Beam Diagnostics for the BNL Energy Recovery Linac Test Facility

    International Nuclear Information System (INIS)

    Cameron, Peter; Ben-Zvi, Ilan; Blaskiewicz, Michael; Brennan, Michael; Connolly, Roger; Dawson, William; Degen, Chris; DellaPenna, Al; Gassner, David; Kesselman, Martin; Kewish, Jorg; Litvinenko, Vladimir; Mead, Joseph; Oerter, Brian; Russo, Tom; Vetter, Kurt; Yakimenko, Vitaly

    2004-01-01

    An Energy Recovery Linac (ERL) test facility is presently under construction at BNL. The goals of this test facility are first to demonstrate stable intense CW electron beam with parameters typical for the RHIC e-cooling project (and potentially for eRHIC), second to test novel elements of the ERL (high current CW photo-cathode, superconducting RF cavity with HOM dampers, and feedback systems), and finally to test lattice dependence of stability criteria. Planned diagnostics include position monitors, loss monitors, transverse profile monitors (both optical and wires), scrapers/halo monitors, a high resolution differential current monitor, phase monitors, an energy spread monitor, and a fast transverse monitor (for beam break-up studies and the energy feedback system). We discuss diagnostics challenges that are unique to this project, and present preliminary system specifications. In addition, we include a brief discussion of the timing system

  1. The role of rapid diagnostic tests in managing adults with pneumonia in low-resource settings

    Directory of Open Access Journals (Sweden)

    Stephen J Aston

    2014-06-01

    Full Text Available In well-resourced settings the systematic use of rapid diagnostics tests (e.g. pneumococcal urinary antigen test that define the causal pathogen to direct therapy has not resulted in significantly improved outcomes in adults with pneumonia. The management of pneumonia in many low-resource settings is complicated by a substantial burden of tuberculosis and HIV-associated opportunistic infections, in addition to the usual spectrum of pathogens seen in well-resourced settings. Clinical features alone do not reliably distinguish between these different aetiologies and physicians often have to treat empirically. Given the limitations in diagnostic laboratory capability present in most low-resource settings, rapid and point-of-care diagnostic tests could become valuable tools to guide treatment decisions. Pneumococcal and Legionella urinary antigen tests are specific and moderately sensitive, but their utility in low-resource settings is uncertain. The Xpert MTB/RIF (Cepheid, USA platform and rapid assays for urinary lipoarabinomannan can substantially speed up tuberculosis diagnosis; the current challenge is to translate this into earlier treatment and hopefully improve patient outcome. In HIV-infected patients, 1-3-β-D-glucan is a serum marker of Pneumocystis jirovecii infection with excellent sensitivity. Further studies are needed to assess the clinical utility and cost-effectiveness of these rapid diagnostic assays when they are incorporated into treatment algorithms.

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

    Science.gov (United States)

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

    2016-01-01

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

  3. Can Emergency Medicine Residents Predict Cost of Diagnostic Testing?

    Directory of Open Access Journals (Sweden)

    Tainter, Christopher R

    2017-01-01

    Full Text Available Diagnostic testing represents a significant portion of healthcare spending, and cost should be considered when ordering such tests. Needless and excessive spending may occur without an appreciation of the impact on the larger healthcare system. Knowledge regarding the cost of diagnostic testing among emergency medicine (EM residents has not previously been studied. A survey was administered to 20 EM residents from a single ACGME-accredited three-year EM residency program, asking for an estimation of patient charges for 20 commonly ordered laboratory tests and seven radiological exams. We compared responses between residency classes to evaluate whether there was a difference based on level of training. The survey completion rate was 100% (20/20 residents. We noted significant discrepancies between the median resident estimates and actual charge to patient for both laboratory and radiological exams. Nearly all responses were an underestimate of the actual cost. The group median underestimation for laboratory testing was $114, for radiographs $57, and for computed tomography exams was $1,058. There was improvement in accuracy with increasing level of training. This pilot study demonstrates that EM residents have a poor understanding of the charges burdening patients and health insurance providers. In order to make balanced decisions with regard to diagnostic testing, providers must appreciate these factors. Education regarding the cost of providing emergency care is a potential area for improvement of EM residency curricula, and warrants further attention and investigation.

  4. Diagnostic Methods of Helicobacter pylori Infection for Epidemiological Studies: Critical Importance of Indirect Test Validation.

    Science.gov (United States)

    Miftahussurur, Muhammad; Yamaoka, Yoshio

    2016-01-01

    Among the methods developed to detect H. pylori infection, determining the gold standard remains debatable, especially for epidemiological studies. Due to the decreasing sensitivity of direct diagnostic tests (histopathology and/or immunohistochemistry [IHC], rapid urease test [RUT], and culture), several indirect tests, including antibody-based tests (serology and urine test), urea breath test (UBT), and stool antigen test (SAT) have been developed to diagnose H. pylori infection. Among the indirect tests, UBT and SAT became the best methods to determine active infection. While antibody-based tests, especially serology, are widely available and relatively sensitive, their specificity is low. Guidelines indicated that no single test can be considered as the gold standard for the diagnosis of H. pylori infection and that one should consider the method's advantages and disadvantages. Based on four epidemiological studies, culture and RUT present a sensitivity of 74.2-90.8% and 83.3-86.9% and a specificity of 97.7-98.8% and 95.1-97.2%, respectively, when using IHC as a gold standard. The sensitivity of serology is quite high, but that of the urine test was lower compared with that of the other methods. Thus, indirect test validation is important although some commercial kits propose universal cut-off values.

  5. Diagnostic development and support of MHD (magnetohydrodynamics) test facilities

    Energy Technology Data Exchange (ETDEWEB)

    1989-07-01

    Mississippi State University (MSU) is developing diagnostic instruments for Magnetohydrodynamics (MHD) power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for HRSR support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with MHD Energy Center computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. MSU personnel will also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs.

  6. Position-sensitive ionization detectors for ionizing beams diagnostics

    CERN Document Server

    Artemiev, A N; Mikhailov, V; Rezvov, V; Yudin, L

    2002-01-01

    Ionizing detectors for on-line non-destructive monitoring of the geometric parameters of ionizing beams have been proposed. Such a detector can be used on a beamline with a residual gas pressure of about 10 sup - sup 3 -10 sup - sup 6 Torr. It measures the product of ionization of the residual gas by the beam under investigation. An electric field moves the ions through a narrow slit into an analyzer. The analyzer field transforms the energy distribution of the ions into a two-dimensional space distribution on the outer analyzer plane. An Open Image Converter Tube (ICT) with an amplifier consisting of two Micro Channel Plates (MCP) forms an image of the real beam cross-section. This image is registered by a video camera, processed and stored on a computer. The detectors were successfully tested on beams of charged particles with wide energy and intensity ranges and on synchrotron radiation beams. Codes developed give the distribution of the beam density along its cross-section, beam profiles, the position of ...

  7. Estimating the true accuracy of diagnostic tests for dengue infection using bayesian latent class models.

    Directory of Open Access Journals (Sweden)

    Wirichada Pan-ngum

    Full Text Available Accuracy of rapid diagnostic tests for dengue infection has been repeatedly estimated by comparing those tests with reference assays. We hypothesized that those estimates might be inaccurate if the accuracy of the reference assays is not perfect. Here, we investigated this using statistical modeling.Data from a cohort study of 549 patients suspected of dengue infection presenting at Colombo North Teaching Hospital, Ragama, Sri Lanka, that described the application of our reference assay (a combination of Dengue IgM antibody capture ELISA and IgG antibody capture ELISA and of three rapid diagnostic tests (Panbio NS1 antigen, IgM antibody and IgG antibody rapid immunochromatographic cassette tests were re-evaluated using bayesian latent class models (LCMs. The estimated sensitivity and specificity of the reference assay were 62.0% and 99.6%, respectively. Prevalence of dengue infection (24.3%, and sensitivities and specificities of the Panbio NS1 (45.9% and 97.9%, IgM (54.5% and 95.5% and IgG (62.1% and 84.5% estimated by bayesian LCMs were significantly different from those estimated by assuming that the reference assay was perfect. Sensitivity, specificity, PPV and NPV for a combination of NS1, IgM and IgG cassette tests on admission samples were 87.0%, 82.8%, 62.0% and 95.2%, respectively.Our reference assay is an imperfect gold standard. In our setting, the combination of NS1, IgM and IgG rapid diagnostic tests could be used on admission to rule out dengue infection with a high level of accuracy (NPV 95.2%. Further evaluation of rapid diagnostic tests for dengue infection should include the use of appropriate statistical models.

  8. Laboratory evaluation of immunochromatographic rapid diagnostic tests for cholera in Haiti.

    Directory of Open Access Journals (Sweden)

    Wilfredo R Matias

    Full Text Available Rapid diagnostic tests (RDT for cholera are promising tools for detecting cholera in areas with limited laboratory infrastructure. However, evidence on the characteristics of the many available RDTs is scarce, and their use has been limited by suboptimal performance. We evaluated the performance characteristics of three cholera RDTs from Span Diagnostics, Artron Laboratories, and Standard Diagnostics in a regional laboratory in Haiti.We retrospectively reviewed records from May 2014 to October 2015 of a laboratory-based surveillance program for Vibrio cholerae at Hôpital Saint-Nicolas in Saint-Marc, Haiti. We compared the results of 511 Crystal VC, 129 Artron and 451 SD Bioline RDTs to bacterial culture as the gold standard. Of 905 cultures, 477 (52.7% were positive for V. cholerae O1, of which 27.7% were serotype Inaba. No cultures grew V. cholerae O139. Sensitivity and specificity of Crystal VC were 98.6% (95%CI: 96.5%-99.6% and 71.1% (95%CI: 64.7%-76.9%, respectively. Artron demonstrated a sensitivity of 98.6% (95%CI: 92.7%-100% and specificity of 69.1% (95%CI: 55.2%-80.9%. SD Bioline demonstrated a sensitivity of 81.1% (95%CI: 75.6%-85.8% and specificity of 92.8% (95%CI: 88.4%-95.9%. Crystal VC and Artron frequently showed false positive O139 bands, whereas none were seen with SD Bioline.There is significant variation in the performance of different cholera diagnostic RDTs. Artron and Crystal VC RDTs have high sensitivity and low specificity, while SD Bioline RDT has low to moderate sensitivity and high specificity when performed by laboratory technicians in Haiti. Study limitations included its retrospective design. The suboptimal characteristics of these tests limit their use as clinical point-of-care tests; however, they may be useful in outbreak response, surveillance, and research in resource-limited settings.

  9. Improving prescribing practices with rapid diagnostic tests (RDTs)

    DEFF Research Database (Denmark)

    Burchett, Helen E D; Leurent, Baptiste; Baiden, Frank

    2017-01-01

    OBJECTIVES: The overuse of antimalarial drugs is widespread. Effective methods to improve prescribing practice remain unclear. We evaluated the impact of 10 interventions that introduced rapid diagnostic tests for malaria (mRDTs) on the use of tests and adherence to results in different contexts....... DESIGN: A comparative case study approach, analysing variation in outcomes across different settings. SETTING: Studies from the ACT Consortium evaluating mRDTs with a range of supporting interventions in 6 malaria endemic countries. Providers were governmental or non-governmental healthcare workers...... characteristics fitted with their own priorities. Goodness of fit of mRDTs with existing consultation and diagnostic practices appeared crucial to maximising the impact of mRDTs on care, as did prior familiarity with malaria testing; adequate human resources and supplies; possible alternative treatments for m...

  10. Latent class analysis of diagnostic tests for visceral leishmaniasis in Brazil.

    Science.gov (United States)

    Machado de Assis, Tália Santana; Rabello, Ana; Werneck, Guilherme Loureiro

    2012-10-01

    To estimate the sensitivities and specificities of different diagnostic tests for visceral leishmaniasis (VL) using latent class analysis (LCA).   This study was performed using data from a prospective study conducted in four Brazilian states from May 2004 to May 2007. Five diagnostic tests for VL were evaluated in 285 VL cases and 119 non-cases: microscopy, indirect fluorescence antibody test (IFAT), enzyme-linked immunosorbent assay using recombinant K39 antigen (rK39-ELISA), direct agglutination test (DAT) and the rK39 rapid test. Microscopy showed sensitivity of 77.0% (CI: 71.5-81.5) and specificity of 99.0% (CI: 94.0-99.7). The IFAT and the DAT showed similar sensitivities, 88.3% (CI: 84.0-92.0) and 88.5% (CI: 84.1-92.0), respectively, but the DAT had a higher specificity (95.4%, CI: 89.2-98.1) than did the IFAT (83.0%, CI: 75.0-88.2). The rK39-ELISA and the rK39 rapid test showed sensitivities of 99.0% (CI: 96.3-99.6) and 94.0% (CI: 90.1-96.3), and specificities of 82.5% (CI: 75.0-88.3) and 100% (CI: 97.0-100.0%), respectively. Considering the lack of an adequate reference standard, LCA proved to be a useful tool in validating diagnostic methods for VL. The DAT and the rK39 rapid test showed better performance. Thus, clinically suspected cases of VL in a Brazilian endemic area could be treated based on the positivity of one of these tests. © 2012 Blackwell Publishing Ltd.

  11. [Comparison between two diagnostic tests for preterm rupture of membrane].

    Science.gov (United States)

    Ramírez Martínez, Jenny Judith; Soria López, Juan Antonio; Ambriz López, Roberto; Iglesias Benavides, José Luis

    2012-03-01

    Rupture premature of membranes occurs in 8% of all births constituting one of main causes of prematurity. Determine qualitatively the presence of human chorionic gonadotropin hormone in vagina and used as diagnostic test to rupture of membranes. We performed a study of diagnostic test observational, transverse, comparative, prospective, not blind type; in 175 healthy pregnant woman with 20 to 42 weeks of gestation, with suspicion of vaginal liquid outlet, at the Obstetrics Department Academic Hospital "Dr Jose Eleuterio Gonzalez" during the period of April 2009 to June 2011, crystallography and vaginal human chorionic gonadotropin hormone test were performed. We analyzed 175 patients, average age was 22.35 years old, was obtained sensibility and specificity of 98.90% y 77.38% to crystallography and 93.41% y 73.81% to vaginal human chorionic gonadotropin hormone test, with value positive predictive of 79.44% and value negative predictive of 91.18% for this last. Determine qualitatively the presence of human chorionic gonadotropin hormone in vagina is a diagnostic test useful for detecting premature rupture of membranes has been shown to be as effective as crystallography.

  12. A simple nomogram for sample size for estimating sensitivity and specificity of medical tests

    Directory of Open Access Journals (Sweden)

    Malhotra Rajeev

    2010-01-01

    Full Text Available Sensitivity and specificity measure inherent validity of a diagnostic test against a gold standard. Researchers develop new diagnostic methods to reduce the cost, risk, invasiveness, and time. Adequate sample size is a must to precisely estimate the validity of a diagnostic test. In practice, researchers generally decide about the sample size arbitrarily either at their convenience, or from the previous literature. We have devised a simple nomogram that yields statistically valid sample size for anticipated sensitivity or anticipated specificity. MS Excel version 2007 was used to derive the values required to plot the nomogram using varying absolute precision, known prevalence of disease, and 95% confidence level using the formula already available in the literature. The nomogram plot was obtained by suitably arranging the lines and distances to conform to this formula. This nomogram could be easily used to determine the sample size for estimating the sensitivity or specificity of a diagnostic test with required precision and 95% confidence level. Sample size at 90% and 99% confidence level, respectively, can also be obtained by just multiplying 0.70 and 1.75 with the number obtained for the 95% confidence level. A nomogram instantly provides the required number of subjects by just moving the ruler and can be repeatedly used without redoing the calculations. This can also be applied for reverse calculations. This nomogram is not applicable for testing of the hypothesis set-up and is applicable only when both diagnostic test and gold standard results have a dichotomous category.

  13. Diagnostic Accuracy of the Slump Test for Identifying Neuropathic Pain in the Lower Limb.

    Science.gov (United States)

    Urban, Lawrence M; MacNeil, Brian J

    2015-08-01

    Diagnostic accuracy study with nonconsecutive enrollment. To assess the diagnostic accuracy of the slump test for neuropathic pain (NeP) in those with low to moderate levels of chronic low back pain (LBP), and to determine whether accuracy of the slump test improves by adding anatomical or qualitative pain descriptors. Neuropathic pain has been linked with poor outcomes, likely due to inadequate diagnosis, which precludes treatment specific for NeP. Current diagnostic approaches are time consuming or lack accuracy. A convenience sample of 21 individuals with LBP, with or without radiating leg pain, was recruited. A standardized neurosensory examination was used to determine the reference diagnosis for NeP. Afterward, the slump test was administered to all participants. Reports of pain location and quality produced during the slump test were recorded. The neurosensory examination designated 11 of the 21 participants with LBP/sciatica as having NeP. The slump test displayed high sensitivity (0.91), moderate specificity (0.70), a positive likelihood ratio of 3.03, and a negative likelihood ratio of 0.13. Adding the criterion of pain below the knee significantly increased specificity to 1.00 (positive likelihood ratio = 11.9). Pain-quality descriptors did not improve diagnostic accuracy. The slump test was highly sensitive in identifying NeP within the study sample. Adding a pain-location criterion improved specificity. Combining the diagnostic outcomes was very effective in identifying all those without NeP and half of those with NeP. Limitations arising from the small and narrow spectrum of participants with LBP/sciatica sampled within the study prevent application of the findings to a wider population. Diagnosis, level 4-.

  14. The dilemma of diagnostic testing for Prader-Willi syndrome

    Science.gov (United States)

    Hung, Dorothy

    2017-01-01

    Although Prader-Willi syndrome (PWS) is a well-described clinical dysmorphic syndrome, DNA testing is required for a definitive diagnosis. A definitive diagnosis can be made in approximately 99% of cases using DNA testing; there are a number of DNA tests that can be used for this purpose, although there is no set standard algorithm of testing. The dilemma arises because of the complex genetic mechanisms at the basis of PWS, which need to be elucidated. To establish the molecular mechanism with a complete work up, involves at least 2 tests. Here we discuss the commonly used tests currently available and suggest a cost—effective approach to diagnostic testing. PMID:28164030

  15. Prospective evaluation of three rapid diagnostic tests for diagnosis of human leptospirosis.

    Directory of Open Access Journals (Sweden)

    Marga G A Goris

    Full Text Available BACKGROUND: Diagnosis of leptospirosis by the microscopic agglutination test (MAT or by culture is confined to specialized laboratories. Although ELISA techniques are more common, they still require laboratory facilities. Rapid Diagnostic Tests (RDTs can be used for easy point-of-care diagnosis. This study aims to evaluate the diagnostic performance of the RDTs LeptoTek Dri Dot, LeptoTek Lateral Flow, and Leptocheck-WB, prospectively. METHODOLOGY: During 2001 to 2012, one or two of the RDTs at the same time have been applied prior to routine diagnostics (MAT, ELISA and culture on serum specimens from participants sent in for leptospirosis diagnosis. The case definition was based on MAT, ELISA and culture results. Participants not fulfilling the case definition were considered not to have leptospirosis. The diagnostic accuracy was determined based on the 1(st submitted sample and paired samples, either in an overall analysis or stratified according to days post onset of illness. RESULTS: The overall sensitivity and specificity for the LeptoTek Dri Dot was 75% respectively 96%, for the LeptoTek Lateral Flow 78% respectively 95%, and for the Leptocheck-WB 78% respectively 98%. Based on the 1(st submitted sample the sensitivity was low (51% for LeptoTek Dri Dot, 69% for LeptoTek Lateral Flow, and 55% for Leptocheck-WB, but substantially increased when the results of paired samples were combined, although accompanied by a lower specificity (82% respectively 91% for LeptoTek Dri Dot, 86% respectively 84% for LeptoTek Lateral Flow, and 80% respectively 93% for Leptocheck-WB. CONCLUSIONS: All three tests present antibody tests contributing to the diagnosis of leptospirosis, thus supporting clinical suspicion and contributing to awareness. Since the overall sensitivity of the tested RDTs did not exceed 80%, one should be cautious to rely only on an RDT result, and confirmation by reference tests is strongly recommended.

  16. Advantages and disadvantages of current diagnostic tests for the detection of Helicobacter pylori.

    Science.gov (United States)

    Mégraud, F

    1996-01-01

    Current tests used to detect Helicobacter pylori are either invasive (histological detection, culture, the polymerase chain reaction (PCR), smear examination) or non-invasive (serology, 13C-urea breath test). These tests vary in their sensitivity and specificity, and the choice of test will depend on the situation, for example, whether the test is to detect infection or the success of eradication treatment. The accuracy of histological tests depends, to a large degree, on the expertise of the pathologist, while the accuracy of culture can depend on the conditions in which the specimen is transported and processed. When performed under optimal conditions, both techniques give very good results. The PCR test has similar sensitivity and specificity to histological and culture tests but a strict protocol must be followed to avoid contamination with H. pylori DNA. The rapid urease test (with a reading taken 1 hour later) is suitable for diagnosis before treatment but its sensitivity decreases after treatment. Smear examination has limited sensitivity. The urea breath test and serology (specific IgG detected by enzyme-linked immunosorbent assay with purified antigens) have sensitivities close to those using the best of the biopsy methods. Other points to consider when selecting a test are its availability, the rapidity of the results (which can range from a few minutes to 2 weeks), possibilities for retrospective analysis, quantification and the detection of pathogenic properties, the globality of certain tests that present an overall picture of the stomach, thus avoiding errors in sampling, and the cost of the test. Important added value can be gained from certain tests: histology allows evaluation of the status of the mucosa, culture allows strain typing and tests for antibiotic susceptibility, and the breath test can confirm successful eradication without endoscopy. When the diagnostic tests are performed correctly, most of them are highly accurate.

  17. Integrated rapid-diagnostic-test reader platform on a cellphone.

    Science.gov (United States)

    Mudanyali, Onur; Dimitrov, Stoyan; Sikora, Uzair; Padmanabhan, Swati; Navruz, Isa; Ozcan, Aydogan

    2012-08-07

    We demonstrate a cellphone-based rapid-diagnostic-test (RDT) reader platform that can work with various lateral flow immuno-chromatographic assays and similar tests to sense the presence of a target analyte in a sample. This compact and cost-effective digital RDT reader, weighing only ~65 g, mechanically attaches to the existing camera unit of a cellphone, where various types of RDTs can be inserted to be imaged in reflection or transmission modes under light-emitting diode (LED)-based illumination. Captured raw images of these tests are then digitally processed (within less than 0.2 s per image) through a smart application running on the cellphone for validation of the RDT, as well as for automated reading of its diagnostic result. The same smart application then transmits the resulting data, together with the RDT images and other related information (e.g., demographic data), to a central server, which presents the diagnostic results on a world map through geo-tagging. This dynamic spatio-temporal map of various RDT results can then be viewed and shared using internet browsers or through the same cellphone application. We tested this platform using malaria, tuberculosis (TB) and HIV RDTs by installing it on both Android-based smartphones and an iPhone. Providing real-time spatio-temporal statistics for the prevalence of various infectious diseases, this smart RDT reader platform running on cellphones might assist healthcare professionals and policymakers to track emerging epidemics worldwide and help epidemic preparedness.

  18. 13CO2-breath tests as diagnostic tools in gastroenterology

    International Nuclear Information System (INIS)

    Ghoos, Y.; Geypens, B.; Maes, B.; Hiele, M.; Rutgeerts, P.

    1994-01-01

    The diagnostic breath test in gastroenterology and hepatology uses specifically 13 C-labelled substrate containing a ''target bond'' which, on enzymatic cleavage, results in the release of a functional group destined to produce labelled 13 CO 2 as a metabolic end product. Advantages and methodology of the 13 CO 2 breath tests are presented together with the calculation methods for 13 C dose ratios. An example is given with the 13 C-octanoic acid breath test to measure gastric emptying of solids. 2 figs., 5 refs

  19. The diagnostic value of a modified Neer test in identifying subacromial impingement syndrome.

    Science.gov (United States)

    Guosheng, Yu; Chongxi, Ren; Guoqing, Cui; Junling, Xu; Hailong, Ji

    2017-12-01

    Subacromial impingement syndrome (SAIS) is characterized by pain experienced through an arc of elevation as the shoulder abducts and diagnosed commonly by Neer test (NT). However, the diagnostic accuracy of NT for SAIS is still limited. Here, a modified Neer test (MNT) was introduced to improve the accuracy of the clinical examination in diagnosing SAIS and differentiating it from frozen shoulder. The aim of this study was to investigate the diagnostic values of MNT in diagnosing SAIS and differentiating it from frozen shoulder. Between January 2015 and June 2015, a prospective study assessed 85 shoulders among 82 patients with shoulder joint disease; 42 patients underwent arthroscopic surgery, and all 82 patients received X-rays, magnetic resonance imaging (MRI) or MRI contrast examinations. The diagnostic criteria are based on arthroscopy and MRI scanning. Using clinical epidemiology and diagnostic tests, we calculated the sensitivity, specificity, positive predictive value, negative predictive value and degree of accuracy of MNT in diagnosing SAIS. The diagnostic accuracy rate of MNT in identifying shoulder SAIS was 90.59%, and the specificity was 95.56%. In the diagnosis of SAIS, MNT is a reliable and highly accurate maneuver and seems useful to distinguish this syndrome from frozen shoulder.

  20. The impact of new trends in POCTs for companion diagnostics, non-invasive testing and molecular diagnostics.

    Science.gov (United States)

    Huckle, David

    2015-06-01

    Point-of-care diagnostics have been slowly developing over several decades and have taken on a new importance in current healthcare delivery for both diagnostics and development of new drugs. Molecular diagnostics have become a key driver of technology change and opened up new areas in companion diagnostics for use alongside pharmaceuticals and in new clinical approaches such as non-invasive testing. Future areas involving smartphone and other information technology advances, together with new developments in molecular biology, microfluidics and surface chemistry are adding to advances in the market. The focus for point-of-care tests with molecular diagnostic technologies is focused on advancing effective applications.

  1. 42 CFR 414.508 - Payment for a new clinical diagnostic laboratory test.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Payment for a new clinical diagnostic laboratory... SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.508 Payment for a new clinical diagnostic laboratory test. For a new clinical diagnostic laboratory test that is assigned a new or...

  2. A Review of Neuropathic Pain: From Diagnostic Tests to Mechanisms

    OpenAIRE

    Truini, Andrea

    2017-01-01

    Neuropathic pain develops when the somatosensory nervous system is affected by a lesion or disease. Diagnostic tests aimed at assessing somatosensory afferent pathway damage are therefore useful for diagnosing neuropathic pain. Neuropathic pain manifests with a range of different symptoms such as ongoing burning pain, squeezing or pressure pain, paroxysmal electric shock-like sensations, stabbing pain, or mechanical dynamic allodynia. The various types of neuropathic pain are associated with ...

  3. Sensitivity and Specificity of Proposed "DSM-5" Diagnostic Criteria for Autism Spectrum Disorder

    Science.gov (United States)

    McPartland, James C.; Reichow, Brian; Volkmar, Fred R.

    2012-01-01

    Objective: This study evaluated the potential impact of proposed "DSM-5" diagnostic criteria for autism spectrum disorder (ASD). Method: The study focused on a sample of 933 participants evaluated during the "DSM-IV" field trial; 657 carried a clinical diagnosis of an ASD, and 276 were diagnosed with a non-autistic disorder. Sensitivity and…

  4. Bivariate analysis of sensitivity and specificity produces informative summary measures in diagnostic reviews

    NARCIS (Netherlands)

    Reitsma, Johannes B.; Glas, Afina S.; Rutjes, Anne W. S.; Scholten, Rob J. P. M.; Bossuyt, Patrick M.; Zwinderman, Aeilko H.

    2005-01-01

    Background and Objectives: Studies of diagnostic accuracy most often report pairs of sensitivity and specificity. We demonstrate the advantage of using bivariate meta-regression models to analyze such data. Methods: We discuss the methodology of both the summary Receiver Operating Characteristic

  5. A general diagnostic model applied to language testing data.

    Science.gov (United States)

    von Davier, Matthias

    2008-11-01

    Probabilistic models with one or more latent variables are designed to report on a corresponding number of skills or cognitive attributes. Multidimensional skill profiles offer additional information beyond what a single test score can provide, if the reported skills can be identified and distinguished reliably. Many recent approaches to skill profile models are limited to dichotomous data and have made use of computationally intensive estimation methods such as Markov chain Monte Carlo, since standard maximum likelihood (ML) estimation techniques were deemed infeasible. This paper presents a general diagnostic model (GDM) that can be estimated with standard ML techniques and applies to polytomous response variables as well as to skills with two or more proficiency levels. The paper uses one member of a larger class of diagnostic models, a compensatory diagnostic model for dichotomous and partial credit data. Many well-known models, such as univariate and multivariate versions of the Rasch model and the two-parameter logistic item response theory model, the generalized partial credit model, as well as a variety of skill profile models, are special cases of this GDM. In addition to an introduction to this model, the paper presents a parameter recovery study using simulated data and an application to real data from the field test for TOEFL Internet-based testing.

  6. Bayesian analysis of longitudinal Johne's disease diagnostic data without a gold standard test

    DEFF Research Database (Denmark)

    Wang, C.; Turnbull, B.W.; Nielsen, Søren Saxmose

    2011-01-01

    A Bayesian methodology was developed based on a latent change-point model to evaluate the performance of milk ELISA and fecal culture tests for longitudinal Johne's disease diagnostic data. The situation of no perfect reference test was considered; that is, no “gold standard.” A change-point proc...... an area under the receiver operating characteristic curve (AUC) of 0.984, and is superior to the raw ELISA (AUC = 0.911) and fecal culture (sensitivity = 0.358, specificity = 0.980) tests for Johne's disease diagnosis....

  7. Clonality Testing in Veterinary Medicine: A Review With Diagnostic Guidelines.

    Science.gov (United States)

    Keller, S M; Vernau, W; Moore, P F

    2016-07-01

    The accurate distinction of reactive and neoplastic lymphoid proliferations can present challenges. Given the different prognoses and treatment strategies, a correct diagnosis is crucial. Molecular clonality assays assess rearranged lymphocyte antigen receptor gene diversity and can help differentiate reactive from neoplastic lymphoid proliferations. Molecular clonality assays are commonly used to assess atypical, mixed, or mature lymphoid proliferations; small tissue fragments that lack architecture; and fluid samples. In addition, clonality testing can be utilized to track neoplastic clones over time or across anatomic sites. Molecular clonality assays are not stand-alone tests but useful adjuncts that follow clinical, morphologic, and immunophenotypic assessment. Even though clonality testing provides valuable information in a variety of situations, the complexities and pitfalls of this method, as well as its dependency on the experience of the interpreter, are often understated. In addition, a lack of standardized terminology, laboratory practices, and interpretational guidelines hinders the reproducibility of clonality testing across laboratories in veterinary medicine. The objectives of this review are twofold. First, the review is intended to familiarize the diagnostic pathologist or interested clinician with the concepts, potential pitfalls, and limitations of clonality testing. Second, the review strives to provide a basis for future harmonization of clonality testing in veterinary medicine by providing diagnostic guidelines. © The Author(s) 2016.

  8. Diagnostic performance of urine dipstick test for urinary tract infection screening in individuals with spinal cord injury

    Directory of Open Access Journals (Sweden)

    Patpiya Sirasaporn

    2016-01-01

    Full Text Available Objectives: To determine the diagnostic performance of urine dipstick test for urinary tract infection (UTI screening in spinal cord injury (SCI patients. Study Design: A cross-sectional diagnostic study. Setting: Srinagarind Hospital, Khon Kaen, Thailand. Participants: SCI patients with neurogenic bladder. Materials and Methods: This study was a cross-sectional diagnostic study that compared the urine dipstick test (index test with the National Institute on Disability and Rehabilitation Research (NIDRR criteria (gold standard test in SCI patients. The urine dipstick test reported positive and negative results. Moreover, the NIDRR criteria classified participants as patients with UTI and patients with no UTI. The diagnostic performance of urine dipstick test for UTI screening was measured in terms of sensitivity, specificity, positive predictive value (PPV, negative predictive value (NPV, positive likelihood ratio (+LR, and negative likelihood ratio (-LR and was summarized in percentage with 95% confidence interval (CI. Results: Out of the 77 participants, most of participants were paraplegia (74%. The combined nitrite and leukocyte esterase urine dipstick test showed the highest sensitivity (93%, PPV (79%, NPV (85%, and +LR (2.39, respectively. The urine dipstick test of nitrite gave the highest specificity (69%. The most common uropathogen was Escherichia coli (33%. Conclusion: In SCI patients, the combined positive nitrite and leukocyte esterase urine dipstick test showed the highest sensitivity. The combined nitrite and leukocyte esterase urine dipstick test should be promoted as a screening test for UTI in SCI patients.

  9. Use of Diagnostic Tests in Adolescents With Essential Hypertension

    Science.gov (United States)

    Yoon, Esther Y.; Cohn, Lisa; Rocchini, Albert; Kershaw, David; Freed, Gary; Ascione, Frank; Clark, Sarah

    2012-01-01

    Objective To describe the use of diagnostic tests in adolescents with essential hypertension. Design Longitudinal analysis of administrative claims data. Setting Michigan Medicaid program during 2003 to 2008. Participants Adolescents with 3 or more years of Medicaid eligibility (≥11 months/y) who had a diagnosis of essential hypertension and 1 or more antihypertensive medication pharmacy claims. Main Outcome Measures We examined adolescents' echocardiogram use and compared it with electrocardiogram (EKG) and renal ultrasonography use. We examined timing of the 3 diagnostic tests in relation to the first pharmacy claim. We examined patient demographics and presence of obesity-related comorbidities. Results During 2003 to 2008, there were 951 adolescents with essential hypertension who had antihypertensive pharmacy claims; 24% (226) had echocardiograms; 22% (207) had renal ultrasonography; and 50% (478) had EKGs. Males (odds ratio [OR], 1.53; 95% CI, 1.06–2.21), younger adolescents (OR, 1.69; 95% CI, 1.17–2.44), those who had EKGs (OR, 5.79; 95% CI, 4.02–8.36), and those who had renal ultrasonography (OR, 2.22; 95% CI, 1.54–3.20) were more likely to obtain echocardiograms compared with females, older adolescents, and adolescents who did not have EKGs or renal ultrasonography. Conclusions Guideline-recommended diagnostic tests—echocardiograms and renal ultrasonography—were equally poorly used by adolescents with essential hypertension. Sex and age differences exist in the use of echocardiograms by adolescents with essential hypertension. The decision and choice of diagnostic tests to evaluate adolescents with essential hypertension warrant further study to understand the underlying rationale for those decisions and to determine treatment effectiveness. PMID:22825544

  10. Developing and Standardization of a Diagnostic Reading Test

    Directory of Open Access Journals (Sweden)

    Tahereh Sima-Shirazi

    2004-06-01

    Full Text Available Objective: This paper is a report on the development, structure and content of a diagnostic dyslexia reading test. The target population of this test is persian children who have problems in learning reading and may be considered as dyslexic. This diagnostic test is the first reading test developed for the native speakers of persian. Materials & Methods: The theoretical framework of the test is based on two well- established reading tests for the English speaking children, namely Durrell Analysis of Reading and Neale Analysis of Reading Ability. The linguistic content of the subtests is selected from the vocabulary and texts of the textbook used in the primary schools. Both the vocabulary and the sentences of the parrallel passeges were controlled for frequency, phonemic/graphemic regularity, syllable structure, morphology, syntax and semantics. They were also controlled for value judgement by two linguistics and three first grader teachers.The first version of the test is normed on 605 boy and girl first graders from different educational sectors and schools selected randomly.The method used in this research is cross- sectional, descriptive- analytic and the data analysis is based on pearson, and mann-whitney u. Results: Reliability of the test is calculated based on parrallel forms (~ 90% and validity is based on content validity.This test has a supplementary section including spelling, graphem/ phoneme correspondness, nonword reading, irregular word reading, and copy subtests. Conclusion: Considering highreliability and precise validation of the test it can be used to diagnose the dyslexia and related linguistic impairments.

  11. A limitation of the diagnostic-odds ratio in determining an optimal cut-off value for a continuous diagnostic test.

    Science.gov (United States)

    Böhning, Dankmar; Holling, Heinz; Patilea, Valentin

    2011-10-01

    The article considers the diagnostic odds ratio, a special summarising function of specificity and sensitivity for a given diagnostic test, which has been suggested as a measure of diagnostic discriminatory power. In the situation of a continuous diagnostic test a cut-off value has to be chosen and it is a common practice to choose the cut-off value on the basis of the maximised diagnostic odds ratio. We show that this strategy is not to be recommended since it might easily lead to cut-off values on the boundary of the parameter range. This is illustrated by means of some examples. The source of the deficient behaviour of the diagnostic odds ratio lies in the convexity of the log-diagnostic odds ratio as a function of the cut-off value. This can easily be seen in practice by plotting a non-parametric estimate of the log-DOR against the cut-off value. In fact, it is shown for the case of a normal distributed diseased and a normal distributed non-diseased population with equal variances that the log-DOR is a convex function of the cut-off value. It is also shown that these problems are not present for the Youden index, which appears to be a better choice.

  12. Assessment of diagnostics and antimicrobial susceptibility testing of Brachyspira species using a ring test

    DEFF Research Database (Denmark)

    Rasback, T.; Fellstrøm, C.; Bergsjo, B.

    2005-01-01

    There is no ring test for quality assessment available in Europe for diagnostics and antimicrobial susceptibility testing of the fastidious, anaerobic bacteria of the genus Brachyspira. Therefore, an international ring test for Brachyspira spp. was performed once a year during 2002-2004. Two sets...

  13. Comparison of diagnostic accuracy of non invasive tests for helicobacter pylori infection in children

    International Nuclear Information System (INIS)

    Hafeez, A.; Haseeb, H.A.H.; Bilal, R.; Latif, Z.

    2007-01-01

    To compare urea breath and stool antigen in children, with histological diagnosis for Helicobacter pylori (H.pylori) infection. Children between 3 and 15 years of age reporting in pediatric outpatient department with upper gastrointestinal symptoms were included. All the participating children underwent an upper gastrointestinal endoscopy and 3 tests namely: histopathological identification of H. pylori (the traditional gold standard), urea breath test and stool antigen test were carried out on each child. The sensitivity, specificity, and positive predictive values were calculated for each noninvasive test used in the study. A total of 54 patients completed the study with a mean age of 8.2 years. On histological examination, 72% (39) were positive for H. pylori infection. On gross endoscopic examination, only 9 patients had signs of gastritis as compared to 39 histological positives. The sensitivity, specificity and positive predictive value of stool antigen test were: 77%, 73% and 89% respectively whereas the same for urea breath test were: 79%, 80% and 91% respectively. Both the noninvasive tests were found to be sensitive and specific as compared with histological identification, for the diagnosis of H. pylori in our pediatric population. The accuracy of urea breath test was better than the stool antigen test but later was easier to perform and could fulfill the criteria for a rapid bedside diagnostic test. (author)

  14. Galvanic skin response test: a new quantitative diagnostic method for Frey syndrome.

    Science.gov (United States)

    Tuzemen, Gokhan; Basut, Oguz; Ozmen, Omer Afsin; Coskun, Hamdi Hakan

    2013-07-01

    Frey syndrome is one of the most common complications following parotid surgery. The current most common test for objectively diagnosing Frey syndrome is Minor starch-iodine test. This test might be insufficient because its results are not quantitative and therefore tests with quantitative results are investigated. The objective of this study was to investigate the efficiency of galvanic skin response (GSR) test, which measures changes in skin resistance, as a method with quantitative results for diagnosis of Frey syndrome. Thirty patients who underwent superficial parotidectomy were assessed postoperatively (mean, 24.7 ± 25.7 months; range, 6-109 months). Patients completed a symptomatic evaluation questionnaire and underwent Minor starch-iodine test and GSR. Diagnostic validity of GSR test was found to be >2.91 following analysis. Sensitivity and specificity of this value were 100% and 55%, respectively, based on symptomatic assessment. Sensitivity and specificity were 87.5% and 57.1%, respectively, based on Minor starch-iodine test. When compared to symptomatic evaluation of patients who underwent superficial parotidectomy, GSR test was shown to be 100% sensitive in diagnosing Frey syndrome and quantitative results of GSR test could determine severity of Frey syndrome.

  15. Comparison of diagnostic accuracy of non-invasive tests for Helicobacter pylori infection in children.

    Science.gov (United States)

    Hafeez, Assad; Bilal, Rakhshanda; Haseeb, Hafsa Amtul; Khan, Umar Farooq; Latif, Zahid; Hassan, Mumtaz

    2007-05-01

    To compare urea breath and stool antigen in children, with histological diagnosis for Helicobacter pylori (H.pylori) infection. Cross-sectional study. From June 2005 to December 2005 carried out at KRL Hospital, Islamabad and Children Hospital, PIMS, Islamabad. Children between 3 and 15 years of age reporting in pediatric outpatient department with upper gastrointestinal symptoms were included. All the participating children underwent an upper gastrointestinal endoscopy and 3 tests namely: histopathological identification of H. pylori (the traditional gold standard), urea breath test and stool antigen test were carried out on each child. The sensitivity, specificity, and positive predictive values were calculated for each noninvasive test used in the study. A total of 54 patients completed the study with a mean age of 8.2 years. On histological examination, 72% (39) were positive for H. pylori infection. On gross endoscopic examination, only 9 patients had signs of gastritis as compared to 39 histological positives. The sensitivity, specificity and positive predictive value of stool antigen test were: 77%, 73% and 89% respectively whereas the same for urea breath test were: 79%, 80% and 91% respectively. Both the noninvasive tests were found to be sensitive and specific as compared with histological identification, for the diagnosis of H. pylori in our pediatric population. The accuracy of urea breath test was better than the stool antigen test but later was easier to perform and could fulfill the criteria for a rapid bedside diagnostic test.

  16. Evaluation of a rapid diagnostic test for yaws infection in a community surveillance setting.

    Directory of Open Access Journals (Sweden)

    Michael Marks

    2014-09-01

    Full Text Available Yaws is a non-venereal treponemal infection caused by Treponema pallidum ssp. pertenue. The WHO has launched a worldwide control programme, which aims to eradicate yaws by 2020. The development of a rapid diagnostic test (RDT for serological diagnosis in the isolated communities affected by yaws is a key requirement for the successful implementation of the WHO strategy. We conducted a study to evaluate the utility of the DPP test in screening for yaws, utilizing samples collected as part of a community prevalence survey conducted in the Solomon Islands. 415 serum samples were tested using both traditional syphilis serology (TPPA and quantitative RPR and the Chembio DPP Syphilis Screen and Confirm RDT. We calculated the sensitivity and specificity of the RDT as compared to gold standard serology. The sensitivity of the RDT against TPPA was 58.5% and the specificity was 97.6%. The sensitivity of the RDT against RPR was 41.7% and the specificity was 95.2%. The sensitivity of the DPP was strongly related to the RPR titre with a sensitivity of 92.0% for an RPR titre of >1/16. Wider access to DPP testing would improve our understanding of worldwide yaws case reporting and the test may play a key role in assessing patients presenting with yaws like lesions in a post-mass drug administration (MDA setting.

  17. Combining computer adaptive testing technology with cognitively diagnostic assessment.

    Science.gov (United States)

    McGlohen, Meghan; Chang, Hua-Hua

    2008-08-01

    A major advantage of computerized adaptive testing (CAT) is that it allows the test to home in on an examinee's ability level in an interactive manner. The aim of the new area of cognitive diagnosis is to provide information about specific content areas in which an examinee needs help. The goal of this study was to combine the benefit of specific feedback from cognitively diagnostic assessment with the advantages of CAT. In this study, three approaches to combining these were investigated: (1) item selection based on the traditional ability level estimate (theta), (2) item selection based on the attribute mastery feedback provided by cognitively diagnostic assessment (alpha), and (3) item selection based on both the traditional ability level estimate (theta) and the attribute mastery feedback provided by cognitively diagnostic assessment (alpha). The results from these three approaches were compared for theta estimation accuracy, attribute mastery estimation accuracy, and item exposure control. The theta- and alpha-based condition outperformed the alpha-based condition regarding theta estimation, attribute mastery pattern estimation, and item exposure control. Both the theta-based condition and the theta- and alpha-based condition performed similarly with regard to theta estimation, attribute mastery estimation, and item exposure control, but the theta- and alpha-based condition has an additional advantage in that it uses the shadow test method, which allows the administrator to incorporate additional constraints in the item selection process, such as content balancing, item type constraints, and so forth, and also to select items on the basis of both the current theta and alpha estimates, which can be built on top of existing 3PL testing programs.

  18. Diagnostic accuracy of a rapid urine lipoarabinomannan test for tuberculosis in HIV-infected adults

    Science.gov (United States)

    Nakiyingi, Lydia; Moodley, V. Mischka; Manabe, Yukari C.; Nicol, Mark P.; Holshouser, Molly; Armstrong, Derek T.; Zemanay, Widaad; Sikhondze, Welile; Mbabazi, Olive; Nonyane, Bareng A.S.; Shah, Maunank; Joloba, Moses L.; Alland, David; Ellner, Jerrold J.; Dorman, Susan E.

    2014-01-01

    Objective In settings of high HIV prevalence, tuberculosis control and patient management are hindered by lack of accurate, rapid tuberculosis diagnostic tests that can be performed at point-of-care. The Determine TB LAM Ag (‘TB LAM’) test is a lateral flow immunochromatographic test for detection of mycobacterial lipoarabinomannan (LAM) in urine. Our objective was to determine sensitivity and specificity of the TB LAM test for tuberculosis diagnosis. Design Prospective diagnostic accuracy study. Setting Hospital and outpatient settings in Uganda and South Africa. Participants HIV-infected adults with tuberculosis symptoms and/or signs. Methods Participants provided a fresh urine specimen for TB LAM testing, blood for mycobacterial culture, and two respiratory specimens for smear microscopy and mycobacterial culture. Main outcome measures For the TB LAM test, sensitivity in participants with culture-positive tuberculosis and specificity in participants without tuberculosis. Results 1013 participants were enrolled. Among culture-positive tuberculosis patients, the TB LAM test identified 136/367 (37.1%) overall and 116/196 (59.2%) in the group with CD4≤100 cells/mm3. The test was specific in 559/573 (97.6%) of patients without tuberculosis. Sensitivity of the urine TB LAM test plus sputum smear microscopy was 197/367 (53.7%) overall and 133/196 (67.9%) among those with CD4≤100. CD4≤50 (adjusted odds ratio [AOR] 6.2, P<0.001) or 51–100 (AOR 7.1, P<0.001), mycobacteremia (AOR 6.1; P<0.01) and hospitalization (AOR 2.6, P=0.03) were independently associated with a positive TB LAM test. Conclusions In HIV-positive adults with CD4≤100, the TB LAM urine test detected over half of culture-positive tuberculosis patients, in less than 30 minutes and without the need for equipment or reagents. PMID:24675585

  19. Methodology in diagnostic laboratory test research in clinical chemistry and clinical chemistry and laboratory medicine.

    Science.gov (United States)

    Lumbreras-Lacarra, Blanca; Ramos-Rincón, José Manuel; Hernández-Aguado, Ildefonso

    2004-03-01

    The application of epidemiologic principles to clinical diagnosis has been less developed than in other clinical areas. Knowledge of the main flaws affecting diagnostic laboratory test research is the first step for improving its quality. We assessed the methodologic aspects of articles on laboratory tests. We included articles that estimated indexes of diagnostic accuracy (sensitivity and specificity) and were published in Clinical Chemistry or Clinical Chemistry and Laboratory Medicine in 1996, 2001, and 2002. Clinical Chemistry has paid special attention to this field of research since 1996 by publishing recommendations, checklists, and reviews. Articles were identified through electronic searches in Medline. The strategy combined the Mesh term "sensitivity and specificity" (exploded) with the text words "specificity", "false negative", and "accuracy". We examined adherence to seven methodologic criteria used in the study by Reid et al. (JAMA1995;274:645-51) of papers published in general medical journals. Three observers evaluated each article independently. Seventy-nine articles fulfilled the inclusion criteria. The percentage of studies that satisfied each criterion improved from 1996 to 2002. Substantial improvement was observed in reporting of the statistical uncertainty of indices of diagnostic accuracy, in criteria based on clinical information from the study population (spectrum composition), and in avoidance of workup bias. Analytical reproducibility was reported frequently (68%), whereas information about indeterminate results was rarely provided. The mean number of methodologic criteria satisfied showed a statistically significant increase over the 3 years in Clinical Chemistry but not in Clinical Chemistry and Laboratory Medicine. The methodologic quality of the articles on diagnostic test research published in Clinical Chemistry and Clinical Chemistry and Laboratory Medicine is comparable to the quality observed in the best general medical journals

  20. Accuracy of an Immunochromatographic Diagnostic Test (ICT Malaria Combo Cassette Test) Compared to Microscopy among under Five-Year-Old Children when Diagnosing Malaria in Equatorial Guinea.

    Science.gov (United States)

    Portero, José-Luis; Rubio-Yuste, Maria; Descalzo, Miguel Angel; Raso, Jose; Lwanga, Magdalena; Obono, Jaquelina; Nseng, Gloria; Benito, Agustin; Cano, Jorge

    2010-01-01

    Conventional malaria diagnosis based on microscopy raises serious difficulties in weak health systems. Cost-effective and sensitive rapid diagnostic tests have been recently proposed as alternatives to microscopy. In Equatorial Guinea, a study was conducted to assess the reliability of a rapid diagnostic test compared to microscopy. The study was designed in accordance with the directives of the Standards for Reporting Diagnostic Accuracy Initiative (STARD). Peripheral thick and thin films for the microscopy diagnosis and a rapid immunochromatographic test (ICT Malaria Combo Cassette Test) were performed on under five-year-old children with malaria suspicion. The ICT test detected Plasmodium spp. infection with a sensitivity of 81.5% and a specificity of 81.9% while P. falciparum diagnosis occurred with a sensitivity of 69.7% and a specificity of 73.7%. The sensitivity of the ICT test increased with higher parasitemias. The general results showed little concordance between the ICT test and microscopy (kappa = 0.28, se: 0.04). In Equatorial Guinea, the ICT Malaria Combo Cassette Test has proven to be an acceptable test to detect high P. falciparum parasitemias. However, the decrease of sensitivity at medium and low parasitemias hampers that ICT can replace properly performed microscopy at present in the diagnosis of malaria in children.

  1. Accuracy of an Immunochromatographic Diagnostic Test (ICT Malaria Combo Cassette Test) Compared to Microscopy among under Five-Year-Old Children when Diagnosing Malaria in Equatorial Guinea

    Science.gov (United States)

    Portero, José-Luis; Rubio-Yuste, Maria; Descalzo, Miguel Angel; Raso, Jose; Lwanga, Magdalena; Obono, Jaquelina; Nseng, Gloria; Benito, Agustin; Cano, Jorge

    2010-01-01

    Conventional malaria diagnosis based on microscopy raises serious difficulties in weak health systems. Cost-effective and sensitive rapid diagnostic tests have been recently proposed as alternatives to microscopy. In Equatorial Guinea, a study was conducted to assess the reliability of a rapid diagnostic test compared to microscopy. The study was designed in accordance with the directives of the Standards for Reporting Diagnostic Accuracy Initiative (STARD). Peripheral thick and thin films for the microscopy diagnosis and a rapid immunochromatographic test (ICT Malaria Combo Cassette Test) were performed on under five-year-old children with malaria suspicion. The ICT test detected Plasmodium spp. infection with a sensitivity of 81.5% and a specificity of 81.9% while P. falciparum diagnosis occurred with a sensitivity of 69.7% and a specificity of 73.7%. The sensitivity of the ICT test increased with higher parasitemias. The general results showed little concordance between the ICT test and microscopy (kappa = 0.28, se: 0.04). In Equatorial Guinea, the ICT Malaria Combo Cassette Test has proven to be an acceptable test to detect high P. falciparum parasitemias. However, the decrease of sensitivity at medium and low parasitemias hampers that ICT can replace properly performed microscopy at present in the diagnosis of malaria in children. PMID:22332024

  2. Transplantation of the sensitized patient: histocompatibility testing.

    Science.gov (United States)

    Montgomery, Robert A; Leffell, Mary S; Zachary, Andrea A

    2013-01-01

    A component necessary for successful transplantation of the sensitized patient is timely and high quality support from the histocompatibility laboratory that helps guide selection of the best route to transplantation and the clinical care of the patient. Responsibilities of the laboratory include risk assessment, HLA typing, and accurate antibody characterization.

  3. Patch test sensitivity to Kathon CG.

    Science.gov (United States)

    Hjorth, N; Roed-Petersen, J

    1986-03-01

    Among 1511 consecutive patients patch tested with Kathon CG at 100 ppm active ingredient, 13 (0.8%) gave a positive reaction. Use test with a lotion containing Kathon CG (8.6 ppm) revealed no reaction in 11 patients with a positive patch test. It is concluded that a positive patch test reaction to 100 ppm does not initiate eczema after use of products preserved with Kathon CG in the low concentrations (3-15 ppm) used in final products.

  4. Ultra-Sensitive Colorimetric Plasmonic Sensing and Microfluidics for Biofluid Diagnostics Using Nanohole Array

    Directory of Open Access Journals (Sweden)

    Abid Ameen

    2015-01-01

    Full Text Available Colorimetric techniques provide a useful approach for sensing application because of their low cost, use of inexpensive equipment, requirement of fewer signal transduction hardware, and, above all, their simple-to-understand results. Colorimetric sensor can be used for both qualitative analyte identification as well as quantitative analysis for many application areas such as clinical diagnosis, food quality control, and environmental monitoring. A gap exists between high-end, accurate, and expensive laboratory equipment and low-cost qualitative point-of-care testing tools. Here, we present a label-free plasmonic-based colorimetric sensor fabricated on a transparent plastic substrate consisting of about one billion nanocups in an array with a subwavelength opening and decorated with metal nanoparticles on the side walls, to bridge that gap. The fabrication techniques of the plasmonic sensor, integration to portable microfluidic devices for lab on chip applications, demonstration of highly sensitive refractive-index sensing, DNA hybridization detection, and protein-protein interaction will be reviewed. Further, we anticipate that the colorimetric sensor can be applied to point-of-care diagnostics by utilizing proper surface functionalization techniques, which seems to be one of the current limiting factors. Finally, the future outlook for the colorimetric plasmonic sensors is discussed.

  5. DiagTest3Grp: An R Package for Analyzing Diagnostic Tests with Three Ordinal Groups

    Directory of Open Access Journals (Sweden)

    Jingqin Luo

    2012-10-01

    Full Text Available Medical researchers endeavor to identify potentially useful biomarkers to develop marker-based screening assays for disease diagnosis and prevention. Useful summary measures which properly evaluate the discriminative ability of diagnostic markers are critical for this purpose. Literature and existing software, for example, R packages nicely cover summary measures for diagnostic markers used for the binary case (e.g., healthy vs. diseased. An intermediate population at an early disease stage usually exists between the healthy and the fully diseased population in many disease processes. Supporting utilities for three-group diagnostic tests are highly desired and important for identifying patients at the early disease stage for timely treatments. However, application packages which provide summary measures for three ordinal groups are currently lacking. This paper focuses on two summary measures of diagnostic accuracy—volume under the receiver operating characteristic surface and the extended Youden index, with three diagnostic groups. We provide the R package DiagTest3Grp to estimate, under both parametric and nonparametric assumptions, the two summary measures and the associated variances, as well as the optimal cut-points for disease diagnosis. An omnibus test for multiple markers and a Wald test for two markers, on independent or paired samples, are incorporated to compare diagnostic accuracy across biomarkers. Sample size calculation under the normality assumption can be performed in the R package to design future diagnostic studies. A real world application evaluating the diagnostic accuracy of neuropsychological markers for Alzheimer’s disease is used to guide readers through step-by-step implementation of DiagTest3Grp to demonstrate its utility.

  6. Diagnostic accuracy of xpert test in tuberculosis detection: A systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Ravdeep Kaur

    2016-01-01

    Full Text Available Background: World Health Organization (WHO recommends the use of Xpert MTB/RIF assay for rapid diagnosis of tuberculosis (TB and detection of rifampicin resistance. This systematic review was done to know about the diagnostic accuracy and cost-effectiveness of the Xpert MTB/RIF assay. Methods: A systematic literature search was conducted in following databases: Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews, MEDLINE, PUBMED, Scopus, Science Direct and Google Scholar for relevant studies for studies published between 2010 and December 2014. Studies given in the systematic reviews were accessed separately and used for analysis. Selection of studies, data extraction and assessment of quality of included studies was performed independently by two reviewers. Studies evaluating the diagnostic accuracy of Xpert MTB/RIF assay among adult or predominantly adult patients (≥14 years, presumed to have pulmonary TB with or without HIV infection were included in the review. Also, studies that had assessed the diagnostic accuracy of Xpert MTB/RIF assay using sputum and other respiratory specimens were included. Results: The included studies had a low risk of any form of bias, showing that findings are of high scientific validity and credibility. Quantitative analysis of 37 included studies shows that Xpert MTB/RIF is an accurate diagnostic test for TB and detection of rifampicin resistance. Conclusion: Xpert MTB/RIF assay is a robust, sensitive and specific test for accurate diagnosis of tuberculosis as compared to conventional tests like culture and microscopic examination.

  7. Review: Diagnostic accuracy of PCR-based detection tests for Helicobacter Pylori in stool samples.

    Science.gov (United States)

    Khadangi, Fatemeh; Yassi, Maryam; Kerachian, Mohammad Amin

    2017-12-01

    Although different methods have been established to detect Helicobacter pylori (H. pylori) infection, identifying infected patients is an ongoing challenge. The aim of this meta-analysis was to provide pooled diagnostic accuracy measures for stool PCR test in the diagnosis of H. pylori infection. In this study, a systematic review and meta-analysis were carried out on various sources, including MEDLINE, Web of Sciences, and the Cochrane Library from April 1, 1999, to May 1, 2016. This meta-analysis adheres to the guidelines provided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses report (PRISMA Statement). The clinical value of DNA stool PCR test was based on the pooled false positive, false negative, true positive, and true negative of different genes. Twenty-six of 328 studies identified met the eligibility criteria. Stool PCR test had a performance of 71% (95% CI: 68-73) sensitivity, 96% (95% CI: 94-97) specificity, and 65.6 (95% CI: 30.2-142.5) diagnostic odds ratio (DOR) in diagnosis of H. pylori. The DOR of genes which showed the highest performance of stool PCR tests was as follows: 23S rRNA 152.5 (95% CI: 55.5-418.9), 16S rRNA 67.9 (95%CI: 6.4-714.3), and glmM 68.1 (95%CI: 20.1-231.7). The sensitivity and specificity of stool PCR test are relatively in the same spectrum of other diagnostic methods for the detection of H. pylori infection. In descending order of significance, the most diagnostic candidate genes using PCR detection were 23S rRNA, 16S rRNA, and glmM. PCR for 23S rRNA gene which has the highest performance could be applicable to detect H. pylori infection. © 2017 John Wiley & Sons Ltd.

  8. BRAF mutation testing with a rapid, fully integrated molecular diagnostics system

    OpenAIRE

    Janku, Filip; Claes, Bart; Huang, Helen J.; Falchook, Gerald S.; Devogelaere, Benoit; Kockx, Mark; Bempt, Isabelle Vanden; Reijans, Martin; Naing, Aung; Fu, Siqing; Piha-Paul, Sarina A.; Hong, David S.; Holley, Veronica R.; Tsimberidou, Apostolia M.; Stepanek, Vanda M.

    2015-01-01

    Fast and accurate diagnostic systems are needed for further implementation of precision therapy of BRAF-mutant and other cancers. The novel IdyllaTM BRAF Mutation Test has high sensitivity and shorter turnaround times compared to other methods. We used Idylla to detect BRAF V600 mutations in archived formalin-fixed paraffin-embedded (FFPE) tumor samples and compared these results with those obtained using the cobas 4800 BRAF V600 Mutation Test or MiSeq deep sequencing system and with those ob...

  9. Which diagnostic tests are most useful in a chest pain unit protocol?

    Directory of Open Access Journals (Sweden)

    Arnold Jane

    2005-08-01

    Full Text Available Abstract Background The chest pain unit (CPU provides rapid diagnostic assessment for patients with acute, undifferentiated chest pain, using a combination of electrocardiographic (ECG recording, biochemical markers and provocative cardiac testing. We aimed to identify which elements of a CPU protocol were most diagnostically and prognostically useful. Methods The Northern General Hospital CPU uses 2–6 hours of serial ECG / ST segment monitoring, CK-MB(mass on arrival and at least two hours later, troponin T at least six hours after worst pain and exercise treadmill testing. Data were prospectively collected over an eighteen-month period from patients managed on the CPU. Patients discharged after CPU assessment were invited to attend a follow-up appointment 72 hours later for ECG and troponin T measurement. Hospital records of all patients were reviewed to identify adverse cardiac events over the subsequent six months. Diagnostic accuracy of each test was estimated by calculating sensitivity and specificity for: 1 acute coronary syndrome (ACS with clinical myocardial infarction and 2 ACS with myocyte necrosis. Prognostic value was estimated by calculating the relative risk of an adverse cardiac event following a positive result. Results Of the 706 patients, 30 (4.2% were diagnosed as ACS with myocardial infarction, 30 (4.2% as ACS with myocyte necrosis, and 32 (4.5% suffered an adverse cardiac event. Sensitivities for ACS with myocardial infarction and myocyte necrosis respectively were: serial ECG / ST segment monitoring 33% and 23%; CK-MB(mass 96% and 63%; troponin T (using 0.03 ng/ml threshold 96% and 90%. The only test that added useful prognostic information was exercise treadmill testing (relative risk 6 for cardiac death, non-fatal myocardial infarction or arrhythmia over six months. Conclusion Serial ECG / ST monitoring, as used in our protocol, adds little diagnostic or prognostic value in patients with a normal or non-diagnostic

  10. Wavenumber selection based analysis in Raman spectroscopy improves skin cancer diagnostic specificity at high sensitivity levels (Conference Presentation)

    Science.gov (United States)

    Zhao, Jianhua; Zeng, Haishan; Kalia, Sunil; Lui, Harvey

    2017-02-01

    Background: Raman spectroscopy is a non-invasive optical technique which can measure molecular vibrational modes within tissue. A large-scale clinical study (n = 518) has demonstrated that real-time Raman spectroscopy could distinguish malignant from benign skin lesions with good diagnostic accuracy; this was validated by a follow-up independent study (n = 127). Objective: Most of the previous diagnostic algorithms have typically been based on analyzing the full band of the Raman spectra, either in the fingerprint or high wavenumber regions. Our objective in this presentation is to explore wavenumber selection based analysis in Raman spectroscopy for skin cancer diagnosis. Methods: A wavenumber selection algorithm was implemented using variably-sized wavenumber windows, which were determined by the correlation coefficient between wavenumbers. Wavenumber windows were chosen based on accumulated frequency from leave-one-out cross-validated stepwise regression or least and shrinkage selection operator (LASSO). The diagnostic algorithms were then generated from the selected wavenumber windows using multivariate statistical analyses, including principal component and general discriminant analysis (PC-GDA) and partial least squares (PLS). A total cohort of 645 confirmed lesions from 573 patients encompassing skin cancers, precancers and benign skin lesions were included. Lesion measurements were divided into training cohort (n = 518) and testing cohort (n = 127) according to the measurement time. Result: The area under the receiver operating characteristic curve (ROC) improved from 0.861-0.891 to 0.891-0.911 and the diagnostic specificity for sensitivity levels of 0.99-0.90 increased respectively from 0.17-0.65 to 0.20-0.75 by selecting specific wavenumber windows for analysis. Conclusion: Wavenumber selection based analysis in Raman spectroscopy improves skin cancer diagnostic specificity at high sensitivity levels.

  11. Publishing nutrition research: validity, reliability, and diagnostic test assessment in nutrition-related research.

    Science.gov (United States)

    Gleason, Philip M; Harris, Jeffrey; Sheean, Patricia M; Boushey, Carol J; Bruemmer, Barbara

    2010-03-01

    This is the sixth in a series of monographs on research design and analysis. The purpose of this article is to describe and discuss several concepts related to the measurement of nutrition-related characteristics and outcomes, including validity, reliability, and diagnostic tests. The article reviews the methodologic issues related to capturing the various aspects of a given nutrition measure's reliability, including test-retest, inter-item, and interobserver or inter-rater reliability. Similarly, it covers content validity, indicators of absolute vs relative validity, and internal vs external validity. With respect to diagnostic assessment, the article summarizes the concepts of sensitivity and specificity. The hope is that dietetics practitioners will be able to both use high-quality measures of nutrition concepts in their research and recognize these measures in research completed by others. Copyright 2010 American Dietetic Association. Published by Elsevier Inc. All rights reserved.

  12. Diagnostic Efficacy of Modified Coagglutination Test in the Diagnosis of Human Brucellosis

    Directory of Open Access Journals (Sweden)

    Mohite S.T

    2013-07-01

    Full Text Available Background: Laboratory help is must for thediagnosis of human brucellosis due to proteanclinical manifestations. As culture is hazardous,time consuming and less sensitive, serologicaltests are preferred for the diagnosis. Aggluti-nation tests like Rose Bengal PlateTest (RBPT, Serum Agglutination tests (SAT,2-Mercaptoethanol test (2-ME that are com-monly employed for the diagnosis either lacksensitivity or specificity. Coombs test andBrucellacapt though are sensitive and specific,workout costly. Therefore, modifiedcoagglutination test was developed and its di-agnostic efficacy was evaluated. Aims and Ob-jectives: To develop modified coagglutinationtest for the diagnosis of human brucellosis andcompare it with Coombs test. Materials andMethods: Serum samples collected from 191brucellosis patients and 100 controls were sub-jected to 2-ME, Coombs test and modifiedcoagglutination test (MCOAG. Blood culturewas performed by Castaneda’s method in all thepatients. Results: Significant difference in thepositivity rate was seen between MCOAG and2-ME. The results of MCOAG were compa-rable with Coombs test. Conclusions: Modi-fied coagglutination test is a better option toCoombs test for the serodiagnosis of brucel-losis in resource constrained countries as it issensitive, specific and cost effective.

  13. [Culture-Sensitive Aspects in Diagnostics of Mental Distress in Refugees - Two Commented Case Reports].

    Science.gov (United States)

    Nesterko, Yuriy; Kaiser, Marie; Glaesmer, Heide

    2017-04-01

    High levels of mental disorders, especially PTSD, are commonly known among groups of people forced to leave their homeland as a consequence of war-related experiences (e. g. armed conflict, torture or persecution). Depending on the cultural background the perceptions of illnesses vary, different symptom presentation and thereupon different coping strategies respectively expectations towards health care services exist. To minimize the danger of misdiagnosis by different experts working with refugees in the host countries, a culture-sensitive diagnostic approach is needed from the beginning. This article describes important aspects of culture-sensitive diagnostics by means of 2 commented case reports. Special focus is set on the aspect of linguistic and in a broader sense cultural comprehension between therapist, client and if necessary language mediator. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Performance and Pain Tolerability of Current Diagnostic Allergy Skin Prick Test Devices.

    Science.gov (United States)

    Tversky, Jody R; Chelladurai, Yohalakshmi; McGready, John; Hamilton, Robert G

    2015-01-01

    Allergen skin prick testing remains an essential tool for diagnosing atopic disease and guiding treatment. Sensitivity needs to be defined for newly introduced devices. Our aim was to compare the performance of 10 current allergy skin prick test devices. Single- and multiheaded skin test devices (n = 10) were applied by a single operator in a prospective randomized manner. Histamine (1 and 6 mg/mL) and control diluent were introduced at 6 randomized locations onto the upper and lower arms of healthy subjects. Wheal and flare reactions were measured independently by 2 masked technicians. Twenty-four subjects provided consent, and 768 skin tests were placed. Mean wheal diameter among devices differed from 3.0 mm (ComforTen; Hollister-Stier, Spokane, Wash) to 6.8 mm (UniTest PC; Lincoln Diagnostics, Decatur, Ill) using 1 mg/mL histamine (P Diagnostics, Decatur, Ill; and Sharp-Test; Panatrex, Placentia, Calif) using 6 mg/mL histamine (P pain score of less than 4 on a 10-point visual analog scale. Pain scores were higher among women, but this did not reach statistical significance. The Multi-Test PC and the UniTest PC had the lowest pain scores compared with the other devices. All 10 skin prick test devices displayed good analytical sensitivity and specificity; however, 3 mm cannot arbitrarily be used as a positive threshold. The use of histamine at 1 mg/mL is unacceptable for certain devices but may be preferable for the most sensitive devices. On average, there was no pain score difference between multiheaded and single-head devices. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  15. Bayesian latent class models with conditionally dependent diagnostic tests: a case study.

    Science.gov (United States)

    Menten, Joris; Boelaert, Marleen; Lesaffre, Emmanuel

    2008-09-30

    In the assessment of the accuracy of diagnostic tests for infectious diseases, the true disease status of the subjects is often unknown due to the lack of a gold standard test. Latent class models with two latent classes, representing diseased and non-diseased subjects, are often used to analyze this type of data. In its basic format, latent class analysis requires the observed outcomes to be statistically independent conditional on the disease status. In most diagnostic settings, this assumption is highly questionable. During the last decade, several methods have been proposed to estimate latent class models with conditional dependence between the test results. A class of flexible fixed and random effects models were described by Dendukuri and Joseph in a Bayesian framework. We illustrate these models using the analysis of a diagnostic study of three field tests and an imperfect reference test for the diagnosis of visceral leishmaniasis. We show that, as observed earlier by Albert and Dodd, different dependence models may result in similar fits to the data while resulting in different inferences. Given this problem, selection of appropriate latent class models should be based on substantive subject matter knowledge. If several clinically plausible models are supported by the data, a sensitivity analysis should be performed by describing the results obtained from different models and using different priors. Copyright (c) 2008 John Wiley & Sons, Ltd.

  16. Translating microarray data for diagnostic testing in childhood leukaemia

    International Nuclear Information System (INIS)

    Hoffmann, Katrin; Firth, Martin J; Beesley, Alex H; Klerk, Nicholas H de; Kees, Ursula R

    2006-01-01

    Recent findings from microarray studies have raised the prospect of a standardized diagnostic gene expression platform to enhance accurate diagnosis and risk stratification in paediatric acute lymphoblastic leukaemia (ALL). However, the robustness as well as the format for such a diagnostic test remains to be determined. As a step towards clinical application of these findings, we have systematically analyzed a published ALL microarray data set using Robust Multi-array Analysis (RMA) and Random Forest (RF). We examined published microarray data from 104 ALL patients specimens, that represent six different subgroups defined by cytogenetic features and immunophenotypes. Using the decision-tree based supervised learning algorithm Random Forest (RF), we determined a small set of genes for optimal subgroup distinction and subsequently validated their predictive power in an independent patient cohort. We achieved very high overall ALL subgroup prediction accuracies of about 98%, and were able to verify the robustness of these genes in an independent panel of 68 specimens obtained from a different institution and processed in a different laboratory. Our study established that the selection of discriminating genes is strongly dependent on the analysis method. This may have profound implications for clinical use, particularly when the classifier is reduced to a small set of genes. We have demonstrated that as few as 26 genes yield accurate class prediction and importantly, almost 70% of these genes have not been previously identified as essential for class distinction of the six ALL subgroups. Our finding supports the feasibility of qRT-PCR technology for standardized diagnostic testing in paediatric ALL and should, in conjunction with conventional cytogenetics lead to a more accurate classification of the disease. In addition, we have demonstrated that microarray findings from one study can be confirmed in an independent study, using an entirely independent patient cohort

  17. Surface enhanced Raman spectroscopy (SERS) for in vitro diagnostic testing at the point of care

    Science.gov (United States)

    Marks, Haley; Schechinger, Monika; Garza, Javier; Locke, Andrea; Coté, Gerard

    2017-06-01

    Point-of-care (POC) device development is a growing field that aims to develop low-cost, rapid, sensitive in-vitro diagnostic testing platforms that are portable, self-contained, and can be used anywhere - from modern clinics to remote and low resource areas. In this review, surface enhanced Raman spectroscopy (SERS) is discussed as a solution to facilitating the translation of bioanalytical sensing to the POC. The potential for SERS to meet the widely accepted "ASSURED" (Affordable, Sensitive, Specific, User-friendly, Rapid, Equipment-free, and Deliverable) criterion provided by the World Health Organization is discussed based on recent advances in SERS in vitro assay development. As SERS provides attractive characteristics for multiplexed sensing at low concentration limits with a high degree of specificity, it holds great promise for enhancing current efforts in rapid diagnostic testing. In outlining the progression of SERS techniques over the past years combined with recent developments in smart nanomaterials, high-throughput microfluidics, and low-cost paper diagnostics, an extensive number of new possibilities show potential for translating SERS biosensors to the POC.

  18. Surface enhanced Raman spectroscopy (SERS for in vitro diagnostic testing at the point of care

    Directory of Open Access Journals (Sweden)

    Marks Haley

    2017-06-01

    Full Text Available Point-of-care (POC device development is a growing field that aims to develop low-cost, rapid, sensitive in-vitro diagnostic testing platforms that are portable, self-contained, and can be used anywhere – from modern clinics to remote and low resource areas. In this review, surface enhanced Raman spectroscopy (SERS is discussed as a solution to facilitating the translation of bioanalytical sensing to the POC. The potential for SERS to meet the widely accepted “ASSURED” (Affordable, Sensitive, Specific, User-friendly, Rapid, Equipment-free, and Deliverable criterion provided by the World Health Organization is discussed based on recent advances in SERS in vitro assay development. As SERS provides attractive characteristics for multiplexed sensing at low concentration limits with a high degree of specificity, it holds great promise for enhancing current efforts in rapid diagnostic testing. In outlining the progression of SERS techniques over the past years combined with recent developments in smart nanomaterials, high-throughput microfluidics, and low-cost paper diagnostics, an extensive number of new possibilities show potential for translating SERS biosensors to the POC.

  19. [Pilot tests using molecular diagnostic assay cervicovaginal infection during pregnancy].

    Science.gov (United States)

    Beltrán-Montoya, J; Escudero-Gontes, S; Martínez-Huerta, N E; Ávila-Vergara, M A; Morales-Hernández, V; Canchola-Sotelo, C; Palacios-González, B; Vadillo-Ortega, F

    2016-08-01

    The prevalence of cervicovaginal infections during pregnancy has been associated with adverse perinatal outcomes however, the actual approach used for diagnosis is not effective. The aim of this study was to compare the diagnosis of vaginal infections in pregnant women using clinical, molecular diagnostic and traditional microbiological culture in a pilot study, to determine the prevalence and association with the development of preterm labor. We performed a nested cross-sectional study composed by 54 women in a cohort of pregnant women in Mexico City. Cervicovaginal infections were evaluated by clinical methods, microbiology culture and a commercially available molecular biology test. Prevalence of cervicovaginal infections during pregnancy was estimated between 28% and 50% according to methodologies. Considering the clinical diagnosis of preterm labor as the gold standard, all diagnostic tests were poor as predictors of preterm labor. Traditional approaches to establish the significance of cervicovaginal infection in pregnancy are exhausted, so be sought new ways to understand this complex relationship. Meanwhile it is recommended to continue to use traditional methods to identify infections during pregnancy in both knowledge of new methods aimed at understanding these relationships are sophisticated.

  20. Limiting the testing of AST: a diagnostically nonspecific enzyme.

    Science.gov (United States)

    Xu, Qian; Higgins, Trefor; Cembrowski, George S

    2015-09-01

    Annually, millions of pairs of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) tests are ordered. These enzymes are highly correlated, and ALT is far more specific diagnostically than AST. To reduce AST testing, we suggest measuring AST only when ALT exceeds a predetermined limit. We derived the proportions of elevated ASTs that would not be measured based on 15 months of paired inpatient and outpatient ALT and AST data. For inpatients, a 35 U/L ALT limit for initiating AST testing would reduce AST testing by 51%, missing only 3% and 7.5% of ASTs exceeding 50 U/L and 35 U/L, respectively. In outpatients, AST testing can be reduced by more than 65%, with fewer missed elevated ASTs (0.5% and 2% of the ASTs exceeding 50 U/L and 35 U/L, respectively). Conservatively, $100 million could be saved annually in the US health care budget by selectively limiting AST testing in just the US outpatient environment. Copyright© by the American Society for Clinical Pathology.

  1. [Food intolerance: reliability and characteristics of different diagnostic alternative tests].

    Science.gov (United States)

    Palmieri, B; Esposito, A; Capone, S; Fistetto, G; Iannitti, T

    2011-03-01

    The expression "food intolerance" dates back to the ancient Greece and can be generally defined as a sum of unpleasant symptoms of varying etiology that can onset in some patients after the ingestion of various food products. Adverse reactions to food can be divided into toxic and non-toxic. The last ones are classified as immunologically mediated, called "allergies", and non-immunologically mediated, commonly defined as "intolerances". The gut wall is directly involved in these adverse reactions to some foods, since it plays a key role in food absorption and in the regulation of the immunitary system. In this paper we discuss food intolerances and allergies, evaluating the available diagnostic methods and their scientific reliability and focusing on IgG analysis based immunoenzymatic test which is the most relevant test for intolerance diagnosis.

  2. Socioeconomic disparities in diagnostic testing after positive aneuploidy screening.

    Science.gov (United States)

    Wong, Amy E; Dungan, Jeffrey; Feinglass, Joseph; Grobman, William A

    2015-02-01

    The objective of this study was to investigate the association between type of health insurance (Medicaid vs. private) and uptake of diagnostic testing for fetal aneuploidy after a positive screening test result. We performed a retrospective cohort study of pregnant women who underwent aneuploidy screening in the first and/or second trimesters of pregnancy and received positive results. The characteristics of and outcomes for women with Medicaid were compared with those of women with private insurance in both univariable and multivariable analyses. In this study, 75 women with Medicaid and 75 with private insurance were analyzed. Those with Medicaid were younger (33.8 vs. 36.9 years, p aneuploidy screen (35 vs. 57%, p screening for aneuploidy. These results emphasize the potential importance of improved counseling for low-income women. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  3. Diagnostic Accuracy of Quantitative Sensory Testing to Discriminate Inflammatory Toothache and Intraoral Neuropathic Pain.

    Science.gov (United States)

    Porporatti, André Luís; Costa, Yuri Martins; Stuginski-Barbosa, Juliana; Bonjardim, Leonardo Rigoldi; Duarte, Marco Antônio Hungaro; Conti, Paulo César Rodrigues

    2015-10-01

    A differential diagnosis between inflammatory toothache (IT) and intraoral neuropathic pain is challenging. The aim of this diagnostic study was to quantify somatosensory function of subjects with IT (acute pulpitis) and atypical odontalgia (AO, intraoral neuropathic pain) and healthy volunteers and to quantify how accurately quantitative sensory testing (QST) discriminates an IT or AO diagnosis. The sample consisted of 60 subjects equally divided (n = 20) into 3 groups: (1) IT, (2) AO, and (3) control. A sequence of 4 QST methods was performed over the dentoalveolar mucosa in the apical maxillar or mandibular area: mechanical detection threshold, pain detection threshold (PDT), dynamic mechanical allodynia, and temporal summation. One-way analysis of variance, Tukey post hoc analyses, and z score transformation were applied to the data. In addition, the receiver operating characteristic curve analysis, diagnostic accuracy, sensitivity, specificity, likelihood ratios, and diagnostic odds ratio of the QST methods were calculated (α = 5%). Somatosensory abnormalities were found for the AO group, which is consistent with a low detection threshold to touch and pain and the presence of mechanical allodynia. For the IT group, no somatosensory abnormality was observed when compared with the control group. The most accurate QST to discriminate the diagnostic differences between IT and healthy individuals is the PDT. The diagnostic differences between AO and healthy individuals and between IT and AO are best discriminated with the mechanical detection threshold, PDT, and dynamic mechanical allodynia. The proposed QST methods may aid in the differential diagnosis between IT and AO with strong accuracy and may be used as complementary diagnostic tests. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Kirill V Sergueev

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

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

    Science.gov (United States)

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

    2017-11-01

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

  6. Consensus-based reporting standards for diagnostic test accuracy studies for paratuberculosis in ruminants

    DEFF Research Database (Denmark)

    Gardner, Ian A.; Nielsen, Søren Saxmose; Whittington, Richard

    2011-01-01

    The Standards for Reporting of Diagnostic Accuracy (STARD) statement (www.stard-statement.org) was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy...... studies and the finding that incomplete or absent reporting of items in the STARD checklist was associated with overly optimistic estimates of test performance characteristics. Although STARD principles apply broadly, specific guidelines do not exist to account for unique considerations in livestock...... studies such as herd tests, potential use of experimental challenge studies, a more diverse group of testing purposes and sampling designs, and the widespread lack of an ante-mortem reference standard with high sensitivity and specificity. The objective of the present study was to develop a modified...

  7. Continuous-data diagnostic tests for paratuberculosis as a multistage disease

    DEFF Research Database (Denmark)

    Toft, Nils; Nielsen, Søren Saxmose; Jørgensen, Erik

    2005-01-01

    We devised a general method for interpretation of multistage diseases using continuous-data diagnostic tests. As an example, we used paratuberculosis as a multistage infection with 2 stages of infection as well as a noninfected state. Using data from a Danish research project, a fecal culture...... testing scheme was linked to an indirect ELISA and adjusted for covariates (parity, age at first calving, and days in milk). We used the log-transformed optical densities in a Bayesian network to obtain the probabilities for each of the 3 infection stages for a given optical density (adjusted...... for covariates). The strength of this approach was that the uncertainty associated with a test was imposed directly on the individual test result rather than aggregated into the population-based measures of test properties (i.e., sensitivity and specificity)...

  8. A systematic review of the diagnostic accuracy of automated tests for cognitive impairment.

    Science.gov (United States)

    Aslam, Rabeea'h W; Bates, Vickie; Dundar, Yenal; Hounsome, Juliet; Richardson, Marty; Krishan, Ashma; Dickson, Rumona; Boland, Angela; Fisher, Joanne; Robinson, Louise; Sikdar, Sudip

    2018-04-01

    The aim of this review is to determine whether automated computerised tests accurately identify patients with progressive cognitive impairment and, if so, to investigate their role in monitoring disease progression and/or response to treatment. Six electronic databases (Medline, Embase, Cochrane, Institute for Scientific Information, PsycINFO, and ProQuest) were searched from January 2005 to August 2015 to identify papers for inclusion. Studies assessing the diagnostic accuracy of automated computerised tests for mild cognitive impairment (MCI) and early dementia against a reference standard were included. Where possible, sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratios were calculated. The Quality Assessment of Diagnostic Accuracy Studies tool was used to assess risk of bias. Sixteen studies assessing 11 diagnostic tools for MCI and early dementia were included. No studies were eligible for inclusion in the review of tools for monitoring progressive disease and response to treatment. The overall quality of the studies was good. However, the wide range of tests assessed and the non-standardised reporting of diagnostic accuracy outcomes meant that statistical analysis was not possible. Some tests have shown promising results for identifying MCI and early dementia. However, concerns over small sample sizes, lack of replicability of studies, and lack of evidence available make it difficult to make recommendations on the clinical use of the computerised tests for diagnosing, monitoring progression, and treatment response for MCI and early dementia. Research is required to establish stable cut-off points for automated computerised tests used to diagnose patients with MCI or early dementia. © 2018 The Authors. International Journal of Geriatric Psychiatry Published by John Wiley & Sons Ltd.

  9. Diagnostic test accuracy of glutamate dehydrogenase for Clostridium difficile: Systematic review and meta-analysis.

    Science.gov (United States)

    Arimoto, Jun; Horita, Nobuyuki; Kato, Shingo; Fuyuki, Akiko; Higurashi, Takuma; Ohkubo, Hidenori; Endo, Hiroki; Takashi, Nonaka; Kaneko, Takeshi; Nakajima, Atsushi

    2016-07-15

    We performed this systematic review and meta-analysis to assess the diagnostic accuracy of detecting glutamate dehydrogenase (GDH) for Clostridium difficile infection (CDI) based on the hierarchical model. Two investigators electrically searched four databases. Reference tests were stool cell cytotoxicity neutralization assay (CCNA) and stool toxigenic culture (TC). To assess the overall accuracy, we calculated the diagnostic odds ratio (DOR) using a DerSimonian-Laird random-model and area the under hierarchical summary receiver operating characteristics (AUC) using Holling's proportional hazard models. The summary estimate of the sensitivity and the specificity were obtained using the bivariate model. According to 42 reports consisting of 3055 reference positive comparisons, and 26188 reference negative comparisons, the DOR was 115 (95%CI: 77-172, I(2) = 12.0%) and the AUC was 0.970 (95%CI: 0.958-0.982). The summary estimate of sensitivity and specificity were 0.911 (95%CI: 0.871-0.940) and 0.912 (95%CI: 0.892-0.928). The positive and negative likelihood ratios were 10.4 (95%CI 8.4-12.7) and 0.098 (95%CI 0.066-0.142), respectively. Detecting GDH for the diagnosis of CDI had both high sensitivity and specificity. Considering its low cost and prevalence, it is appropriate for a screening test for CDI.

  10. Systematic review and meta-analysis of studies evaluating diagnostic test accuracy: A practical review for clinical researchers-Part II. general guidance and tips

    International Nuclear Information System (INIS)

    Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi; Park, Seong Ho; Lee, June Young

    2015-01-01

    Meta-analysis of diagnostic test accuracy studies differs from the usual meta-analysis of therapeutic/interventional studies in that, it is required to simultaneously analyze a pair of two outcome measures such as sensitivity and specificity, instead of a single outcome. Since sensitivity and specificity are generally inversely correlated and could be affected by a threshold effect, more sophisticated statistical methods are required for the meta-analysis of diagnostic test accuracy. Hierarchical models including the bivariate model and the hierarchical summary receiver operating characteristic model are increasingly being accepted as standard methods for meta-analysis of diagnostic test accuracy studies. We provide a conceptual review of statistical methods currently used and recommended for meta-analysis of diagnostic test accuracy studies. This article could serve as a methodological reference for those who perform systematic review and meta-analysis of diagnostic test accuracy studies

  11. Diagnostic accuracy of synovial fluid, blood markers, and microbiological testing in chronic knee prosthetic infections.

    Science.gov (United States)

    Balato, Giovanni; Franceschini, Vincenzo; Ascione, Tiziana; Lamberti, Alfredo; Balboni, Fiamma; Baldini, Andrea

    2018-02-01

    This retrospective study was undertaken to define cut-off values for synovial fluid (SF) leukocyte count and neutrophil percentage for differentiating aseptic failure and periprosthetic joint infection (PJI) and to evaluate the diagnostic accuracy of blood inflammatory markers, and microbiological testing according to the criteria proposed by the International Consensus Meeting (ICM) of Philadelphia. All patients who underwent revision total knee arthroplasty from January 2010 to July 2015 were included: we identified and classified 31 PJIs and 136 aseptic joints. The diagnostic performance of single test was assessed by receiver operating characteristic curve analyses. The sensitivity and specificity were calculated for each of the cut-off values and the area under the curve (AUC) was calculated. The median SF leukocyte count as well as the neutrophil percentage and inflammatory markers were significantly higher in patients with PJI than in those with aseptic failure (p  2.8 × 10 3 /μL had a sensitivity of 83.8% and a specificity of 89.7% whereas a neutrophil percentage of > 72% yielded a marginally higher sensitivity of 84% and a specificity of 91%. Applying the ICM criteria we found a significant correlation between all these diagnostic measures and PJI (p < 0.001) except for a single positive culture. The most accurate criterion of the ICM was the synovial neutrophil differential (AUC = 0.89; 95% CI 0.81-0.97), followed by SF leukocyte count (AUC = 0.86; 95% CI 0.78-0.94), increased inflammatory markers (AUC = 0.85; 95% CI 0.76-0.93), and two positive periprosthetic cultures (AUC = 0.84; 95% CI 0.73-0.94). The presence of sinus tract communicating with the joint and a single positive culture showed unfavourable diagnostic accuracy (AUC = 0.60, 95% CI 0.47-0.72; AUC = 0.49, 95% CI 0.38-0.61, respectively) CONCLUSIONS: The present study highlights the adequate ability of fluid cell count and neutrophil differential to distinguish between PJI

  12. Diagnostic Accuracy of 3 Physical Examination Tests in the Assessment of Hip Microinstability.

    Science.gov (United States)

    Hoppe, Daniel J; Truntzer, Jeremy N; Shapiro, Lauren M; Abrams, Geoffrey D; Safran, Marc R

    2017-11-01

    Hip microinstability is a diagnosis gaining increasing interest. Physical examination tests to identify microinstability have not been objectively investigated using intraoperative confirmation of instability as a reference standard. To determine the test characteristics and diagnostic accuracy of 3 physical examination maneuvers in the detection of hip microinstability. Cohort study (diagnosis); Level of evidence, 2. A review was conducted of 194 consecutive hip arthroscopic procedures performed by a sports medicine surgeon at a tertiary-care academic center. Physical examination findings of interest, including the abduction-hyperextension-external rotation (AB-HEER) test, the prone instability test, and the hyperextension-external rotation (HEER) test, were obtained from prospectively collected data. The reference standard was intraoperative identification of instability based on previously published objective criteria. Test characteristics, including sensitivity, specificity, positive and negative predictive values, and accuracy, were calculated for each test as well as for combinations of tests. A total of 109 patients were included in the analysis. The AB-HEER test was most accurate, with a sensitivity of 80.6% (95% CI, 70.8%-90.5%) and a specificity of 89.4% (95% CI, 80.5%-98.2%). The prone instability test had a low sensitivity (33.9%) but a very high specificity (97.9%). The HEER test performed second in both sensitivity (71.0%) and specificity (85.1%). The combination of multiple tests with positive findings did not yield significantly greater accuracy. All tests had high positive predictive values (range, 86.3%-95.5%) and moderate negative predictive values (range, 52.9%-77.8%). When all 3 tests had positive findings, there was a 95.0% (95% CI, 90.1%-99.9%) chance that the patient had microinstability. The AB-HEER test most accurately predicted hip instability, followed by the HEER test and the prone instability test. However, the high specificity of the

  13. DIAGNOSTIC TEST OF TORONTO AND MODIFIED TORONTO SCORING, MONOFILAMENT TEST, AND VIBRATE SENSATION TEST USING 128 HZ TUNING FORK FOR DIABETIC POLINEUROPATHY

    Directory of Open Access Journals (Sweden)

    Bethasiwi Purbasari

    2018-01-01

    Full Text Available Background. The prevalence of diabetes mellitus has been epidemically increasing throughout all the world population, and diabetic polyneuropathy (PNP-DM is one of the most common neurologic manifestation of this disease. Clinical research has proved that effective bedside screening of PNP-DM can significantly reduce the incidence of foot ulcer and limb amputation. Objective. To measure the diagnostic test of polyneuropathy scoring, monofilament 10-g SemmesWeinstein test, and 128 Hz tuning fork test as an early detection measure for PNP-DM. Methods. This research was conducted using a cross sectional approach from Januari 2016 to Juli 2017. Results. Among the total study population of 43 (23 men and 20 woman, Modified Toronto Score has the highest sensitivity (100%, PPV (93% and accuracy (93%. Toronto score has the highest NPV (9%. Conclusion. Modified Toronto Score has good diagnostic value as screening tool in PNP-DM.

  14. Supervisory control and diagnostics system for the mirror fusion test facility: overview and status 1980

    International Nuclear Information System (INIS)

    McGoldrick, P.R.

    1981-01-01

    The Mirror Fusion Test Facility (MFTF) is a complex facility requiring a highly-computerized Supervisory Control and Diagnostics System (SCDS) to monitor and provide control over ten subsystems; three of which require true process control. SCDS will provide physicists with a method of studying machine and plasma behavior by acquiring and processing up to four megabytes of plasma diagnostic information every five minutes. A high degree of availability and throughput is provided by a distributed computer system (nine 32-bit minicomputers on shared memory). Data, distributed across SCDS, is managed by a high-bandwidth Distributed Database Management System. The MFTF operators' control room consoles use color television monitors with touch sensitive screens; this is a totally new approach. The method of handling deviations to normal machine operation and how the operator should be notified and assisted in the resolution of problems has been studied and a system designed

  15. Field-testing of the ICHD-3 beta diagnostic criteria for classical trigeminal neuralgia

    DEFF Research Database (Denmark)

    Maarbjerg, Stine; Sørensen, Morten Togo; Gozalov, Aydin

    2015-01-01

    INTRODUCTION: We aimed to field-test the beta version of the third edition of the International Classification of Headache Disorders (ICHD-3 beta) diagnostic criteria for classical trigeminal neuralgia (TN). The proposed beta draft of the 11th version of the International Classification of Diseases...... (ICD-11 beta) is almost exclusively based on the ICHD-3 beta classification structure although slightly abbreviated. We compared sensitivity and specificity to ICHD-2 criteria, and evaluated the needs for revision. METHODS: Clinical characteristics were systematically and prospectively collected from...

  16. Highly sensitive silicon microreactor for catalyst testing

    DEFF Research Database (Denmark)

    Henriksen, Toke Riishøj; Olsen, Jakob Lind; Vesborg, Peter Christian Kjærgaard

    2009-01-01

    by directing the entire gas flow through the catalyst bed to a mass spectrometer, thus ensuring that nearly all reaction products are present in the analyzed gas flow. Although the device can be employed for testing a wide range of catalysts, the primary aim of the design is to allow characterization of model...... catalysts which can only be obtained in small quantities. Such measurements are of significant fundamental interest but are challenging because of the low surface areas involved. The relationship between the reaction zone gas flow and the pressure in the reaction zone is investigated experimentally......, it is found that platinum catalysts with areas as small as 15 mu m(2) are conveniently characterized with the device. (C) 2009 American Institute of Physics. [doi:10.1063/1.3270191]...

  17. Applications of optical fibers in nuclear test diagnostics

    International Nuclear Information System (INIS)

    Lyons, P.B.; Hodson, E.K.; Looney, L.D.

    1980-01-01

    Two new plasma diagnostic experiments have been successfully fielded on nuclear device tests at NTS. Both systems rely on the unique advantages provided by optical fiber technology and both systems provide new diagnostic capabilities that previously were beyond the state-of-the-art in coaxial cable systems. One system addresses the need to record e wide bandwidth data on gamma-ray sources. Over the long (< 1 km) distances that characterize NTS testing, the bandwidth of coaxial cable systems is usually limited to < 200 to 400 MHz even with extensive equalization. The new system uses the Cerenkov process to generate light in a converter material. High bandwidth fibers and detectors are used to approach a 1-GHz bandwidth. In this case fibers provided the bandwidth capability. The second system provides time and space resolution of a neutron source on a fast (ns) time scale. Previous systems have utilized either an array of neutron detectors with individual coaxial cables or a fast scintillator viewed by a gated image intensifier. For a large number of channels, the coaxial system becomes very costly and is subject to potentially severe EMI concerns. The gated intensifier system requires complex electronics and accurate timing and can be affected by EMI. An alternative system is described which provides continuous time coverage with limited spatial resolution. Complete freedom from EMI is achieved through the use of optical data collection and transmission. The optical fibers offered a major (2 to 3 times) cost savings and a large weight savings relative to the coax system. Each system is discussed

  18. Accuracy of Triple Diagnostic Test in Patients with Thyroid Nodule at Dr. Cipto Mangunkusumo General Hospital

    Directory of Open Access Journals (Sweden)

    Diani Kartini

    2017-04-01

    Full Text Available The aim of the study is to evaluate the accuracy of triple diagnostic test on thyroid nodules. The data from patients’ medical records who came to Cipto Mangunkusumo General Hospital for the first time or for evaluation of thyroid nodule and patients who underwent thyroidectomy during 2010 to 2011. Clinical examination was scored by McGill Thyroid Nodule Score. ROC procedure was performed to obtain clinical cut-off scores of diagnosis of malignant. Ultrasonography (USG result was considered malignant for TIRADS 4, 5, and 6. If clinical, USG and histopathology examinations of triple diagnostic give positive results, it will be classified as concordant malignant whereas if all those three show benign results, the classification is benign. Thyroid carcinoma was found in 134 out of 161 patients with thyroid nodule. There were 84 patients with concordant results for all three elements of the triple test. Out of 84 patients with concordant triple diagnostic results, there were 53 malignant cases (32.9% and 31 benign cases (19.3%. Main histopathological findings among patients with thyroid carcinoma was papillary (90.3%, follicular (3%, medullary (0.7%, and anaplastic (6%. The sensitivity and specificity of triple diagnostic was 77% and 94%, with positive predictive value of 98%, negative predictive value of 51,6% and accuracy of 80.9%. Combination of clinical findings, USG, and FNAB gave malignant probability of 92%, better than combination of clinical findings and USG (81.6% or clinical findings and FNAB (87%. Triple diagnostic cannot be used as an ideal test to replace frozen section examination in managing thyroid nodule. However, in cases with concordant results of each triple diagnostic’s element, the positive predictive value (98% and malignant probability (92% is high. Keywords: thyroid nodule, triple diagnostic, accuracy.   Akurasi Metode Triple Diagnostic pada Pasien Nodul Tiroid  di RSUPN Dr. Cipto Mangunkusumo   Abstrak Tujuan

  19. HIV misdiagnosis in sub-Saharan Africa: performance of diagnostic algorithms at six testing sites.

    Science.gov (United States)

    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.

  20. Diagnostic Performance of High Sensitivity Compared with Contemporary Cardiac Troponin I for the Diagnosis of Acute Myocardial Infarction.

    Science.gov (United States)

    Sandoval, Yader; Smith, Stephen W; Thordsen, Sarah E; Bruen, Charles A; Carlson, Michelle D; Dodd, Kenneth W; Driver, Brian E; Jacoby, Katherine; Johnson, Benjamin K; Love, Sara A; Moore, Johanna C; Sexter, Anne; Schulz, Karen; Scott, Nathaniel L; Nicholson, Jennifer; Apple, Fred S

    2017-10-01

    We examined the diagnostic performance of high-sensitivity cardiac troponin I (hs-cTnI) vs contemporary cTnI with use of the 99th percentile alone and with a normal electrocardiogram (ECG) to rule out acute myocardial infarction (MI) and serial changes (deltas) to rule in MI. We included consecutive patients presenting to a US emergency department with serial cTnI onclinical indication. Diagnostic performance for acute MI, including MI subtypes, and 30-day outcomes were examined. Among 1631 patients, MI was diagnosed in 12.9% using the contemporary cTnI assay and in 10.4% using the hs-cTnI assay. For ruling out MI, contemporary cTnI ≤99th percentile at 0, 3, and 6 h and a normal ECG had a negative predictive value (NPV) of 99.5% (95% CI, 98.6-100) and a sensitivity of 99.1% (95% CI, 97.4-100) for diagnostic and safety outcomes. Serial hs-cTnI measurements ≤99th percentile at 0 and 3 h and a normal ECG had an NPV and sensitivity of 100% (95% CI, 100-100) for diagnostic and safety outcomes. For ruling in MI, contemporary cTnI measurements had specificities of 84.4% (95% CI, 82.5-86.3) at presentation and 78.7% (95% CI, 75.4-82.0) with serial testing at 0, 3, and 6 h, improving to 89.2% (95% CI, 87.1-91.3) by using serial cTnI changes (delta, 0 and 6 h) >150%. hs-cTnI had specificities of 86.9% (95% CI, 85.1-88.6) at presentation and 85.7% (95% CI, 83.5-87.9) with serial testing at 0 and 3 h, improving to 89.3% (95% CI, 87.3-91.2) using a delta hs-cTnI (0 and 3 h) >5 ng/L. hs-cTnI and contemporary cTnI assays are excellent in ruling out MI following recommendations predicated on serial testing and the 99th percentile with a normal ECG. For ruling in MI, deltas improve the specificity. ClinicalTrials.gov Identifier: NCT02060760. © 2017 American Association for Clinical Chemistry.

  1. The diagnostic utility of High-Sensitivity Cardiac Troponin T in acute coronary syndrome

    Directory of Open Access Journals (Sweden)

    Manal Mohsen

    2016-03-01

    Conclusion: Our study demonstrated highly significant absolute and relative kinetic changes in hs-TnT levels in patients with AMI. The hs-TnT can be used for early rule in patients with MI as it could detect 97% of cases with MI whose Troponin I was negative and could detect 100% of cases of MI after 6–8 h compared to Troponin I which could detect only 21.2% of cases. This can be of great importance in the future introduction and use of the new high sensitive assay as a non-invasive reliable diagnostic tool to replace the currently used invasive diagnostic techniques for patients with ACS.

  2. Physical examination tests of the shoulder: a systematic review and meta-analysis of diagnostic test performance.

    Science.gov (United States)

    Gismervik, Sigmund Ø; Drogset, Jon O; Granviken, Fredrik; Rø, Magne; Leivseth, Gunnar

    2017-01-25

    Physical examination tests of the shoulder (PETS) are clinical examination maneuvers designed to aid the assessment of shoulder complaints. Despite more than 180 PETS described in the literature, evidence of their validity and usefulness in diagnosing the shoulder is questioned. This meta-analysis aims to use diagnostic odds ratio (DOR) to evaluate how much PETS shift overall probability and to rank the test performance of single PETS in order to aid the clinician's choice of which tests to use. This study adheres to the principles outlined in the Cochrane guidelines and the PRISMA statement. A fixed effect model was used to assess the overall diagnostic validity of PETS by pooling DOR for different PETS with similar biomechanical rationale when possible. Single PETS were assessed and ranked by DOR. Clinical performance was assessed by sensitivity, specificity, accuracy and likelihood ratio. Six thousand nine-hundred abstracts and 202 full-text articles were assessed for eligibility; 20 articles were eligible and data from 11 articles could be included in the meta-analysis. All PETS for SLAP (superior labral anterior posterior) lesions pooled gave a DOR of 1.38 [1.13, 1.69]. The Supraspinatus test for any full thickness rotator cuff tear obtained the highest DOR of 9.24 (sensitivity was 0.74, specificity 0.77). Compression-Rotation test obtained the highest DOR (6.36) among single PETS for SLAP lesions (sensitivity 0.43, specificity 0.89) and Hawkins test obtained the highest DOR (2.86) for impingement syndrome (sensitivity 0.58, specificity 0.67). No single PETS showed superior clinical test performance. The clinical performance of single PETS is limited. However, when the different PETS for SLAP lesions were pooled, we found a statistical significant change in post-test probability indicating an overall statistical validity. We suggest that clinicians choose their PETS among those with the highest pooled DOR and to assess validity to their own specific clinical

  3. Predictive diagnostic value of the tourniquet test for the diagnosis of dengue infection in adults

    Science.gov (United States)

    Mayxay, Mayfong; Phetsouvanh, Rattanaphone; Moore, Catrin E; Chansamouth, Vilada; Vongsouvath, Manivanh; Sisouphone, Syho; Vongphachanh, Pankham; Thaojaikong, Thaksinaporn; Thongpaseuth, Soulignasack; Phongmany, Simmaly; Keolouangkhot, Valy; Strobel, Michel; Newton, Paul N

    2011-01-01

    Objective To examine the accuracy of the admission tourniquet test in the diagnosis of dengue infection among Lao adults. Methods Prospective assessment of the predictive diagnostic value of the tourniquet test for the diagnosis of dengue infection, as defined by IgM, IgG and NS1 ELISAs (Panbio Ltd, Australia), among Lao adult inpatients with clinically suspected dengue infection. Results Of 234 patients with clinically suspected dengue infection on admission, 73% were serologically confirmed to have dengue, while 64 patients with negative dengue serology were diagnosed as having scrub typhus (39%), murine typhus (11%), undetermined typhus (12%), Japanese encephalitis virus (5%), undetermined flavivirus (5%) and typhoid fever (3%); 25% had no identifiable aetiology. The tourniquet test was positive in 29.1% (95% CI = 23.2–34.9%) of all patients and in 34.1% (95% CI = 27.0–41.2%) of dengue-seropositive patients, in 32.7% (95% CI = 23.5–41.8) of those with dengue fever and in 36.4% (95% CI = 24.7–48.0) of those with dengue haemorrhagic fever. Interobserver agreement for the tourniquet test was 90.2% (95% CI = 86.4–94.0) (Kappa = 0.76). Using ELISAs as the diagnostic gold standard, the sensitivity of the tourniquet test was 33.5–34%; its specificity was 84–91%. The positive and negative predictive values were 85–90% and 32.5–34%, respectively. Conclusions The admission tourniquet test has low sensitivity and adds relatively little value to the diagnosis of dengue among Lao adult inpatients with suspected dengue. Although a positive tourniquet test suggests dengue and that treatment of alternative diagnoses may not be needed, a negative test result does not exclude dengue. PMID:20958892

  4. Simple Diagnostic Tests to Detect Toxic Alcohol Intoxications

    Science.gov (United States)

    Shin, Jai Moo; Sachs, George; Kraut, Jeffrey A.

    2008-01-01

    Methanol, ethylene glycol, and diethylene glycol intoxications can produce visual disturbances, neurological disturbances, acute renal failure, pulmonary dysfunction, cardiac dysfunction, metabolic acidosis, and death. Metabolic acidosis and an increased serum osmolality are important clues to their diagnosis. The former reflects the organic acids produced by metabolism of the parent alcohol, while the latter is due to accumulation of the offending alcohol. However, neither the clinical nor the laboratory findings are specific for toxic alcohol ingestions. The definitive diagnosis of the alcohol intoxications is commonly based on detection of the alcohol or its metabolites in blood. Early diagnosis is important, because initiation of appropriate treatment can markedly lessen their morbidity and mortality. At present detection of the parent alcohol in body fluids is inferred from its measurement in blood. This measurement is often performed by specialty laboratories using expensive equipment, and a long delay between obtaining the specimen and getting the results is not unusual. In this report, we describe liquid- based tests that detect methanol, ethylene glycol, diethylene glycol, and ethanol in saliva. The tests are sensitive and they have different specificity for each of the alcohols facilitating distinction among them. The relatively high sensitivity and specificity of the tests as a whole will facilitate the rapid diagnosis of each of these alcohol intoxications. PMID:18940722

  5. Simple diagnostic tests to detect toxic alcohol intoxications.

    Science.gov (United States)

    Shin, Jai Moo; Sachs, George; Kraut, Jeffrey A

    2008-10-01

    Methanol, ethylene glycol, and diethylene glycol intoxications can produce visual disturbances, neurologic disturbances, acute renal failure, pulmonary dysfunction, cardiac dysfunction, metabolic acidosis, and death. Metabolic acidosis and an increased serum osmolality are important clues to their diagnosis. The former reflects the organic acids produced by metabolism of the parent alcohol, whereas the latter is caused by accumulation of the offending alcohol. However, neither the clinical nor the laboratory findings are specific for toxic alcohol ingestions. The definitive diagnosis of the alcohol intoxications is commonly based on detection of the alcohol or its metabolites in blood. Early diagnosis is important, because initiation of appropriate treatment can markedly decrease their rates of morbidity and mortality. Currently, detection of the parent alcohol in body fluids is inferred from its measurement in blood. This measurement is often performed by specialty laboratories using expensive equipment, and a long delay between obtaining the specimen and getting the results is not unusual. In this report, we describe liquid-based tests that detect methanol, ethylene glycol, diethylene glycol, and ethanol in saliva. The tests are sensitive, and they have different specificity for each of the alcohols facilitating distinction among them. The relatively high sensitivity and specificity of the tests as a whole will facilitate the rapid diagnosis of each of these alcohol intoxications.

  6. Bias in logistic regression due to imperfect diagnostic test results and practical correction approaches.

    Science.gov (United States)

    Valle, Denis; Lima, Joanna M Tucker; Millar, Justin; Amratia, Punam; Haque, Ubydul

    2015-11-04

    Logistic regression is a statistical model widely used in cross-sectional and cohort studies to identify and quantify the effects of potential disease risk factors. However, the impact of imperfect tests on adjusted odds ratios (and thus on the identification of risk factors) is under-appreciated. The purpose of this article is to draw attention to the problem associated with modelling imperfect diagnostic tests, and propose simple Bayesian models to adequately address this issue. A systematic literature review was conducted to determine the proportion of malaria studies that appropriately accounted for false-negatives/false-positives in a logistic regression setting. Inference from the standard logistic regression was also compared with that from three proposed Bayesian models using simulations and malaria data from the western Brazilian Amazon. A systematic literature review suggests that malaria epidemiologists are largely unaware of the problem of using logistic regression to model imperfect diagnostic test results. Simulation results reveal that statistical inference can be substantially improved when using the proposed Bayesian models versus the standard logistic regression. Finally, analysis of original malaria data with one of the proposed Bayesian models reveals that microscopy sensitivity is strongly influenced by how long people have lived in the study region, and an important risk factor (i.e., participation in forest extractivism) is identified that would have been missed by standard logistic regression. Given the numerous diagnostic methods employed by malaria researchers and the ubiquitous use of logistic regression to model the results of these diagnostic tests, this paper provides critical guidelines to improve data analysis practice in the presence of misclassification error. Easy-to-use code that can be readily adapted to WinBUGS is provided, enabling straightforward implementation of the proposed Bayesian models.

  7. Sensitivity and Specificity of Clinical and Laboratory Otolith Function Tests.

    Science.gov (United States)

    Kumar, Lokesh; Thakar, Alok; Thakur, Bhaskar; Sikka, Kapil

    2017-10-01

    To evaluate clinic based and laboratory tests of otolith function for their sensitivity and specificity in demarcating unilateral compensated complete vestibular deficit from normal. Prospective cross-sectional study. Tertiary care hospital vestibular physiology laboratory. Control group-30 healthy adults, 20-45 years age; Case group-15 subjects post vestibular shwannoma excision or post-labyrinthectomy with compensated unilateral complete audio-vestibular loss. Otolith function evaluation by precise clinical testing (head tilt test-HTT; subjective visual vertical-SVV) and laboratory testing (headroll-eye counterroll-HR-ECR; vesibular evoked myogenic potentials-cVEMP). Sensitivity and specificity of clinical and laboratory tests in differentiating case and control subjects. Measurable test results were universally obtained with clinical otolith tests (SVV; HTT) but not with laboratory tests. The HR-ECR test did not indicate any definitive wave forms in 10% controls and 26% cases. cVEMP responses were absent in 10% controls.HTT test with normative cutoff at 2 degrees deviations from vertical noted as 93.33% sensitive and 100% specific. SVV test with normative cutoff at 1.3 degrees noted as 100% sensitive and 100% specific. Laboratory tests demonstrated poorer specificities owing primarily to significant unresponsiveness in normal controls. Clinical otolith function tests, if conducted with precision, demonstrate greater ability than laboratory testing in discriminating normal controls from cases with unilateral complete compensated vestibular dysfunction.

  8. Meta-epidemiologic analysis indicates that MEDLINE searches are sufficient for diagnostic test accuracy systematic reviews.

    Science.gov (United States)

    van Enst, Wynanda A; Scholten, Rob J P M; Whiting, Penny; Zwinderman, Aeilko H; Hooft, Lotty

    2014-11-01

    To investigate how the summary estimates in diagnostic test accuracy (DTA) systematic reviews are affected when searches are limited to MEDLINE. A systematic search was performed to identify DTA reviews that had conducted exhaustive searches and included a meta-analysis. Primary studies included in selected reviews were assessed to determine whether they were indexed on MEDLINE. The effect of omitting non-MEDLINE studies from meta-analyses was investigated by calculating the summary relative diagnostic odds ratio (RDORs) = DORMEDLINE only/DORall studies. We also calculated the summary difference in sensitivity and specificity between all studies and only MEDLINE-indexed studies. Ten reviews contributing 15 meta-analyses met inclusion criteria for quantitative analysis. The RDOR comparing MEDLINE-only studies with all studies was 1.04 (95% confidence interval [CI], 0.95, 1.15). Summary estimates of sensitivity and specificity remained almost unchanged (difference in sensitivity: -0.08%; 95% CI -1% to 1%; difference in specificity: -0.1%; 95% CI -0.8% to 1%). Restricting to studies indexed on MEDLINE did not influence the summary estimates of the meta-analyses in our sample. In certain circumstances, for instance, when resources are limited, it may be appropriate to restrict searches to MEDLINE. However, the impact on individual reviews cannot be predicted. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Thermal sensitive paper as a diagnostic for intense relativistic electron beam dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Gilgenbach, R.M.; McDermott, D.B.; Marshall, T.C.

    1978-08-01

    Thermal sensitive paper has been used as a diagnostic for an intense relativistic electron beam propagating in a rippled magnetic field. The E/sub r/ x B/sub z/ rotation of the beam has been measured from the exposed pattern on the thermal paper and used to calculate the electrostatic field of the beam E/sub r/, and the corresponding values of electron density and beam current. Exposed strips of thermal paper show longitudinal modulation of the radial electron velocity with a period corresponding to that of a rippled magnetic field; modulation of the radial electron velocity at the cyclotron frequency has also been observed.

  10. Pathophysiological rationale and diagnostic targets for diastolic stress testing.

    Science.gov (United States)

    Erdei, Tamás; Aakhus, Svend; Marino, Paolo; Paulus, Walter J; Smiseth, Otto A; Fraser, Alan G

    2015-09-01

    Cardiopulmonary functional reserve measured as peak oxygen uptake is predicted better at rest by measures of cardiac diastolic function than by systolic function. Normal adaptations in the trained heart include resting bradycardia, increased LV end-diastolic volume and augmented early diastolic suction on exercise. In normal populations early diastolic relaxation declines with age and end-diastolic stiffness increases, but in healthy older subjects who have exercised throughout their lives diastolic function can be well preserved. The mechanisms by which LV diastolic filling and pressures can be impaired during exercise include reduced early diastolic recoil and suction (which can be exacerbated by increased late systolic loading), increased preload and reduced compliance. Abnormal ventricular-arterial coupling and enhanced ventricular interaction may contribute in particular circumstances. One common final pathway that causes breathlessness is an increase in LV filling pressure and left atrial pressure. Testing elderly subjects with breathlessness of unknown aetiology in order to detect worsening diastolic function during stress is proposed to diagnose heart failure with preserved EF. In invasive studies, the most prominent abnormality is an early and rapid rise in pulmonary capillary wedge pressure. A systematic non-invasive diagnostic strategy would use validated methods to assess different mechanisms of inducible diastolic dysfunction and not just single parameters that offer imprecise estimates of mean LV filling pressure. Protocols should assess early diastolic relaxation and filling as well as late diastolic filling and compliance, as these may be affected separately. Better refined diagnostic targets may translate to more focused treatment. 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.

  11. Field evaluation of a dual rapid diagnostic test for HIV infection and syphilis in Lima, Peru.

    Science.gov (United States)

    Bristow, Claire C; Leon, Segundo R; Huang, Emily; Brown, Brandon J; Ramos, Lourdes B; Vargas, Silver K; Flores, Juan A; Caceres, Carlos F; Klausner, Jeffrey D

    2016-05-01

    Screening for HIV and syphilis in key populations is recommended by the WHO to reduce the morbidity, mortality and transmission associated with undiagnosed and untreated infections. Rapid point-of-care tests that can detect multiple infections with a single fingerprick whole blood specimen using a single device are gaining popularity. We evaluated the field performance of a rapid dual HIV and syphilis test in people at high risk of HIV and syphilis infections. Participants included men who have sex with men and transgender women recruited in Lima, Peru. Reference standard testing for detection of HIV and syphilis infections, conducted using blood samples from venipuncture, included Treponema pallidum particle agglutination and fourth-generation HIV enzyme immunoassay for which positive results had a confirmation HIV Western blot test. For the evaluation test, SD BIOLINE HIV/Syphilis Duo test (Standard Diagnostics, Korea), a fingerprick blood specimen was used. Sensitivity and specificity were calculated and the exact binomial method was used to determine 95% CIs. A total of 415 participants were recruited for the study. The dual test sensitivity for detection of T. pallidum infection was 89.2% (95% CI 83.5% to 93.5%) and specificity 98.8% (95% CI 96.5% to 99.8%). For detection of HIV infection, the sensitivity of the dual test was 99.1% (95% CI 94.8% to 100%) and specificity 99.4% (95% CI 97.7% to 99.9%). This high performing dual test should be considered for the use in clinical settings to increase uptake of simultaneous testing of HIV and syphilis and accelerate time to treatment for those who need it. 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/

  12. Validity, Reliability, and Sensitivity of a Volleyball Intermittent Endurance Test.

    Science.gov (United States)

    Rodríguez-Marroyo, Jose A; Medina-Carrillo, Javier; García-López, Juan; Morante, Juan C; Villa, José G; Foster, Carl

    2017-03-01

    To analyze the concurrent and construct validity of a volleyball intermittent endurance test (VIET). The VIET's test-retest reliability and sensitivity to assess seasonal changes was also studied. During the preseason, 71 volleyball players of different competitive levels took part in this study. All performed the VIET and a graded treadmill test with gas-exchange measurement (GXT). Thirty-one of the players performed an additional VIET to analyze the test-retest reliability. To test the VIET's sensitivity, 28 players repeated the VIET and GXT at the end of their season. Significant (P volleyball players.

  13. Multiplexed and Sensitive DNA Methylation Testing Using Methylation-Sensitive Restriction Enzymes "MSRE-qPCR".

    Science.gov (United States)

    Beikircher, Gabriel; Pulverer, Walter; Hofner, Manuela; Noehammer, Christa; Weinhaeusel, Andreas

    2018-01-01

    DNA methylation is a chemically stable key-player in epigenetics. In the vertebrate genome the 5-methyl cytosine (5mC) has been found almost exclusively in the CpG dinucleotide context. CpG dinucleotides are enriched in CpG islands very frequently located within or close to gene promoters. Analyses of DNA methylation changes in human diagnostics have been conducted classically using methylation-sensitive restriction enzymes (MSRE). Since the discovery of bisulfite conversion-based sequencing and PCR assays, MSRE-based PCR assays have been less frequently used, although especially in the field of cancer epigenetics MSRE-based genome-wide discovery and targeted screening applications have been and are still performed successfully. Even though epigenome-wide discovery of altered DNA methylation patterns has found its way into various fields of human disease and molecular genetics research, the validation of findings upon discovery is still a bottleneck. Usually several multiples of 10 up to 100 candidate biomarkers from discovery have to be confirmed or are of interest for further work. In particular, bisulfite PCR assays are often limited in the number of candidates which can be analyzed, due to their low multiplexing capability, especially, if only small amounts of DNA are available from for example clinical specimens. In clinical research and diagnostics a similar situation arises for the analyses of cell-free DNA (cfDNA) in body fluids or circulating tumor cells (CTCs). Although tissue- or disease- (e.g., cancer) specific DNA methylation patterns can be deduced very efficiently in a genome-wide manner if around 100 ng of DNA are available, confirming these candidates and selecting target-sequences for studying methylation changes in liquid biopsies using cfDNA or CTCs remains a big challenge. Along these lines we have developed MSRE-qPCR and introduce here method details, which have been found very suitable for the efficient confirmation and testing of DNA

  14. Evaluating the Instructional Sensitivity of Four States' Student Achievement Tests

    Science.gov (United States)

    Polikoff, Morgan S.

    2016-01-01

    As state tests of student achievement are used for an increasingly wide array of high- and low-stakes purposes, evaluating their instructional sensitivity is essential. This article uses data from the Bill and Melinda Gates Foundation's Measures of Effective Project to examine the instructional sensitivity of 4 states' mathematics and English…

  15. The Development and Validation of the Vocalic Sensitivity Test.

    Science.gov (United States)

    Villaume, William A.; Brown, Mary Helen

    1999-01-01

    Notes that presbycusis, hearing loss associated with aging, may be marked by a second dimension of hearing loss, a loss in vocalic sensitivity. Reports on the development of the Vocalic Sensitivity Test, which controls for the verbal elements in speech while also allowing for the vocalics to exercise their normal metacommunicative function of…

  16. Diagnostic accuracy and optimal use of three tests for tuberculosis in live badgers.

    Directory of Open Access Journals (Sweden)

    Julian A Drewe

    Full Text Available BACKGROUND: Accurate diagnosis of tuberculosis (TB due to infection with Mycobacterium bovis is notoriously difficult in live animals, yet important if we are to understand the epidemiology of TB and devise effective strategies to limit its spread. Currently available tests for diagnosing TB in live Eurasian badgers (Meles meles remain unvalidated against a reliable gold standard. The aim of the present study was to evaluate the diagnostic accuracy and optimal use of three tests for TB in badgers in the absence of a gold standard. METHODOLOGY/PRINCIPAL FINDINGS: A Bayesian approach was used to evaluate the diagnostic accuracy and optimal use of mycobacterial culture, gamma-interferon assay and a commercially available serological test using multiple samples collected from 305 live wild badgers. Although no single test was judged to be sufficiently sensitive and specific to be used as a sole diagnostic method, selective combined use of the three tests allowed guidelines to be formulated that allow a diagnosis to be made for individual animals with an estimated overall accuracy of 93% (range: 75% to 97%. Employing this approach in the study population of badgers resulted in approximately 13 out of 14 animals having their true infection status correctly classified from samples collected on a single capture. CONCLUSIONS/SIGNIFICANCE: This method of interpretation represents a marked improvement on the current procedure for diagnosing M. bovis infection in live badgers. The results should be of use to inform future test and intervention strategies with the aim of reducing the incidence of TB in free-living wild badger populations.

  17. Battery Test Facility- Electrochemical Analysis and Diagnostics Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Electrochemical Analysis and Diagnostics Laboratory (EADL) provides battery developers with reliable, independent, and unbiased performance evaluations of their...

  18. Testing the validity and acceptability of the diagnostic criteria for Hoarding Disorder: a DSM-5 survey.

    Science.gov (United States)

    Mataix-Cols, D; Fernández de la Cruz, L; Nakao, T; Pertusa, A

    2011-12-01

    The DSM-5 Obsessive-Compulsive Spectrum Sub-Workgroup is recommending the creation of a new diagnostic category named Hoarding Disorder (HD). The validity and acceptability of the proposed diagnostic criteria have yet to be formally tested. Obsessive-compulsive disorder/hoarding experts and random members of the American Psychiatric Association (APA) were shown eight brief clinical vignettes (four cases meeting criteria for HD, three with hoarding behaviour secondary to other mental disorders, and one with subclinical hoarding behaviour) and asked to decide the most appropriate diagnosis in each case. Participants were also asked about the perceived acceptability of the criteria and whether they supported the inclusion of HD in the main manual. Altogether, 211 experts and 48 APA members completed the survey (30% and 10% response rates, respectively). The sensitivity and specificity of the HD diagnosis and the individual criteria were high (80-90%) across various types of professionals, irrespective of their experience with hoarding cases. About 90% of participants in both samples thought the criteria would be very/somewhat acceptable for professionals and sufferers. Most experts (70%) supported the inclusion of HD in the main manual, whereas only 50% of the APA members did. The proposed criteria for HD have high sensitivity and specificity. The criteria are also deemed acceptable for professionals and sufferers alike. Training of professionals and the development and validation of semi-structured diagnostic instruments should improve diagnostic accuracy even further. A field trial is now needed to confirm these encouraging findings with real patients in real clinical settings.

  19. [Diagnostic capacity of skin prick test in egg and cow's milk allergic infants].

    Science.gov (United States)

    Yan, Jun-mei; Chen, Jing; Li, Hai-qi; Hu, Yan

    2011-05-01

    Mean diameter is the most common used parameter for wheal response assessment after skin prick test. This study aimed to investigate the diagnostic capacity of mean diameter according to the outcome of oral food challenge, and to determine the cut-off points that could render food challenges unnecessary. Data of 173 children referred to the Division of Primary Child Health Care for the evaluation of suspected food allergy were prospectively studied. All children underwent skin prick test and open food challenge to the relevant food(s) in clinic. The mean wheal diameter of skin prick test was measured, and open food challenge was performed to confirm food allergy. The SPSS software package version 13.0 for windows (SPSS, Chicago, IL, USA) was used for all statistical analysis. Open food challenge was taken as the gold standard for diagnosis. Diagnostic capacity of skin prick test, including the sensitivity, specificity, positive predictive value, negative predictive value, was calculated by cross-table. In addition, receiver operating characteristic curve (ROC) was plotted and area under the curve (AUC) was calculated to quantify the accuracy of the parameter. For the 173 children, 271 open food challenges were performed with egg white, egg yolk and cow's milk, In which 123 were positive, 99 children were diagnosed as food allergy. Cutaneous symptoms (87.0%) were most common, followed by gastrointestinal symptoms (9.8%). The AUC of mean diameter was 0.794 for egg white, 0.804 for egg yolk and 0.904 for cow's milk. The sensitivity of skin prick test with a cut-off value of ≥ 3 mm was ranged from 71% to 87%, while the specificity was between 31% and 57%. The authors also defined food specific skin prick test mean diameters that were 100% diagnostic for allergy to egg white (≥ 8.5 mm), egg yolk (≥ 5.5 mm), cow's milk (≥ 5.5 mm). Predictive decision points for a positive outcome of food challenges can be calculated for egg and cow's milk using mean diameter. It

  20. Vendor Testing of Sensitive Compounds in Simulated Dry Sludge

    International Nuclear Information System (INIS)

    Dworjanyn, L.O.

    1999-01-01

    This assessment covers thermal screening, differential scanning calorimetry, and impact sensitivity testing on Mercury Fulminate, and mixtures of the fulminate in dry inorganic sludge, which is present in large quantities in a number of storage tanks at Westinghouse Savannah River

  1. Clinical value of the thallium-201 stress test: sensitivity and specificity in the detection of coronary artery disease

    International Nuclear Information System (INIS)

    Okada, R.D.; Raessler, K.L.; Woolfenden, J.M.; Groves, B.M.; Patton, D.; Goldman, S.; Hager, W.D.

    1978-01-01

    Rest and exercise thallium-201 scintigraphy ( 201 Tl stress test), 90% submaximal treadmill exercise test (ECG stress test), and coronary angiography were performed on 49 patients with suspected coronary artery disease. When technically unsatisfactory and uninterpretable scintiphotos were excluded, the sensitivity (true positives/true positives + false negatives) of the 201 Tl stress test in detecting coronary artery stenosis >= 70% was 81%. The sensitivity of the 201 Tl stress test in detecting coronary artery stenosis >= 50% was 84%. However, when technically unsatisfactory and uninterpretable studies were considered as failures of the test to detect disease, the sensitivity of the 201 Tl stress test in detecting coronary artery stenosis >= 50% was 71%. The sensitivity of the ECG stress test was 92% in detecting stenosis >= 70% and 85% in detecting stenosis >= 50% when non-diagnostic tests were excluded. However, when 11 non-diagnostic ECG stress tests were considered as a failure of the test to detect disease, the sensitivity of the ECG stress test in detecting coronary artery stenosis >= 50% was 64%. The sensitivity of the combined stress test in detecting coronary artery stenosis >= 50% was high whether or not technically unsatisfactory and uninterpretable studies were (89%) or were not (94%) included in the analysis. The specificity (true negatives/true negatives + false positives) for >= 50% coronary artery stenosis was 90% for the 201 Tl stress test, 75% for the ECG stress test and 80% for the combined stress test. Combined ECG and 201 Tl stress testing detects a number of patients with significant coronary artery disease missed by ECG stress testing alone, primarily in those cases where the ECG stress test is non-diagnostic. (author)

  2. Transscrotal Near Infrared Spectroscopy as a Diagnostic Test for Testis Torsion in Pediatric Acute Scrotum: A Prospective Comparison to Gold Standard Diagnostic Test Study.

    Science.gov (United States)

    Schlomer, Bruce J; Keays, Melise A; Grimsby, Gwen M; Granberg, Candace F; DaJusta, Daniel G; Menon, Vani S; Ostrov, Lauren; Sheth, Kunj R; Hill, Martinez; Sanchez, Emma J; Harrison, Clanton B; Jacobs, Micah A; Huang, Rong; Burgu, Berk; Hennes, Halim; Baker, Linda A

    2017-09-01

    A rapid test for testicular torsion in children may obviate the delay for testicular ultrasound. In this study we assessed testicular tissue percent oxygen saturation (%StO2) measured by transscrotal near infrared spectroscopy as a diagnostic test for pediatric testicular torsion. This was a prospective comparison to a gold standard diagnostic test study that evaluated near infrared spectroscopy %StO2 readings to diagnose testicular torsion. The gold standard for torsion diagnosis was standard clinical care. From 2013 to 2015 males with acute scrotum for more than 1 month and who were less than 18 years old were recruited. Near infrared spectroscopy %StO2 readings were obtained for affected and unaffected testes. Near infrared spectroscopy Δ%StO2 was calculated as unaffected minus affected reading. The utility of near infrared spectroscopy Δ%StO2 to diagnose testis torsion was described with ROC curves. Of 154 eligible patients 121 had near infrared spectroscopy readings. Median near infrared spectroscopy Δ%StO2 in the 36 patients with torsion was 2.0 (IQR -4.2 to 9.8) vs -1.7 (IQR -8.7 to 2.0) in the 85 without torsion (p=0.004). AUC for near infrared spectroscopy as a diagnostic test was 0.66 (95% CI 0.55-0.78). Near infrared spectroscopy Δ%StO2 of 20 or greater had a positive predictive value of 100% and a sensitivity of 22.2%. Tanner stage 3-5 cases without scrotal edema or with pain for 12 hours or less had an AUC of 0.91 (95% CI 0.86-1.0) and 0.80 (95% CI 0.62-0.99), respectively. In all children near infrared spectroscopy readings had limited utility in diagnosing torsion. However, in Tanner 3-5 cases without scrotal edema or with pain 12 hours or less, near infrared spectroscopy discriminated well between torsion and nontorsion. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  3. Alkaline Comet Assay and Micronucleus Test Parameters in Children Exposed to Diagnostic X-Ray Examination

    International Nuclear Information System (INIS)

    Gajski, G.; Geric, M.; Garaj-Vrhovac, V.; Milkovic, Dj.; Beck, N.; Ranogajec-Komor, M.; Miljanic, S.; Knezevic, Z.

    2011-01-01

    Chest radiograms represent the basic radiological examination of thorax and are the most frequently performed radiological diagnostic procedure in the child population. Understanding the risks of low doses of radiation is an important aspect in the risk benefit analysis in paediatric populations. To provide the best care for the young patients the effects of radiation should be minimized thus chest X-rays must be performed by highest standards to ensure that the young patient has the lowest risk possible. Since children are the most sensitive to radiation, there is a need for follow up of the young populations that receive these X-ray diagnostic examinations. Follow up would be especially advisable for children that are at higher risk of radiation induced damage, for example children with a predisposition to DNA damage, or for children that are constantly exposed to numerous radiological examinations due to their illness. In that manner, present study was undertaken to evaluate application of different dosimetry systems in conjunction with alkaline comet assay and micronucleus test for the assessment of different types of DNA and chromosomal alterations in child population exposed to acute diagnostic X-rays examination. For that purpose doses were measured using thermoluminescence (TL) and radiophotoluminescent (RPL) dosimetry systems. The study demonstrated that immediately after exposure to diagnostic X-irradiation, mean percentage of DNA in tail of the comets, which is indirect measures of DNA damage, was significantly changed. The same was noticed for mean total number of micronuclei as well. It was shown that children with pulmonary diseases subjected to diagnostic procedure develop a significant increase in mean total number of each measured parameter which are the biomarkers of genetic damage for carcinogenesis, than prior to diagnostic procedure and that interindividual differences exist for each monitored child. Our results show that genetic damage arises

  4. Performance of Rapid Diagnostic Tests for Plasmodium ovale Malaria in Japanese Travellers.

    Science.gov (United States)

    Tanizaki, Ryutaro; Kato, Yasuyuki; Iwagami, Moritoshi; Kutsuna, Satoshi; Ujiie, Mugen; Takeshita, Nozomi; Hayakawa, Kayoko; Kanagawa, Shuzo; Kano, Shigeyuki; Ohmagari, Norio

    2014-12-01

    Rapid diagnostic tests (RDTs) are used widely in the diagnosis of malaria. Although the effectiveness of RDTs for malaria has been described in many previous studies, the low performance of RDT particularly for Plasmodium ovale malaria in traveller has rarely been reported. This was a retrospective cohort study conducted on Japanese travellers diagnosed with malaria at the National Center for Global Health and Medicine between January 2004 and June 2013. The diagnosis of malaria was confirmed by microscopic examination, RDT, and polymerase chain reaction in all patients. The RDTs used in our study were Binax NOW Malaria (Binax Inc., Scarborough, Maine, USA) (BN) and SD Malaria Antigen Pf/Pan (Standard Diagnostics Inc., Korea) (SDMA). We compared the sensitivity of the RDTs to P. ovale malaria and Plasmodium vivax malaria. A total of 153 cases of malaria were observed, 113 of which were found among Japanese travellers. Nine patients with P. ovale malaria and 17 patients with P. vivax malaria undergoing RDTs were evaluated. The overall sensitivity of RDTs for P. ovale malaria and P. vivax malaria was 22.2% and 94.1%, respectively (P < 0.001). The sensitivity of SDMA for P. ovale malaria and P. vivax malaria was 50% and 100%, respectively. The sensitivity of BN for P. vivax malaria was 90.0%, but it was ineffective in detecting the cases of P. ovale malaria. The sensitivity of RDTs was not high enough to diagnose P. ovale malaria in our study. In order not to overlook P. ovale malaria, therefore, microscopic examination is indispensable.

  5. Development and validation of a highly sensitive urine-based test to identify patients with colonic adenomatous polyps.

    Science.gov (United States)

    Wang, Haili; Tso, Victor; Wong, Clarence; Sadowski, Dan; Fedorak, Richard N

    2014-03-20

    Adenomatous polyps are precursors of colorectal cancer; their detection and removal is the goal of colon cancer screening programs. However, fecal-based methods identify patients with adenomatous polyps with low levels of sensitivity. The aim or this study was to develop a highly accurate, prototypic, proof-of-concept, spot urine-based diagnostic test using metabolomic technology to distinguish persons with adenomatous polyps from those without polyps. Prospective urine and stool samples were collected from 876 participants undergoing colonoscopy examination in a colon cancer screening program, from April 2008 to October 2009 at the University of Alberta. Colonoscopy reference standard identified 633 participants with no colonic polyps and 243 with colonic adenomatous polyps. One-dimensional nuclear magnetic resonance spectra of urine metabolites were analyzed to define a diagnostic metabolomic profile for colonic adenomas. A urine metabolomic diagnostic test for colonic adenomatous polyps was established using 67% of the samples (un-blinded training set) and validated using the other 33% of the samples (blinded testing set). The urine metabolomic diagnostic test's specificity and sensitivity were compared with those of fecal-based tests. Using a two-component, orthogonal, partial least-squares model of the metabolomic profile, the un-blinded training set identified patients with colonic adenomatous polyps with 88.9% sensitivity and 50.2% specificity. Validation using the blinded testing set confirmed sensitivity and specificity values of 82.7% and 51.2%, respectively. Sensitivities of fecal-based tests to identify colonic adenomas ranged from 2.5 to 11.9%. We describe a proof-of-concept spot urine-based metabolomic diagnostic test that identifies patients with colonic adenomatous polyps with a greater level of sensitivity (83%) than fecal-based tests.

  6. Effectiveness of leucocyte esterase as a diagnostic test for acute septic arthritis.

    Science.gov (United States)

    Gautam, V K; Saini, Rishabh; Sharma, Siddharth

    2017-01-01

    We hypothesized that leucocyte esterase strip test can aid in diagnosing septic arthritis in native synovial fluid because leucocyte esterase concentrations would be elevated at the infection site because of secretion by recruited neutrophils. The cohort included 27 patients (suspected septic arthritis and normal subjects). A standard chemical test strip (graded as negative, trace, +, ++ or +++) was used to detect the presence of leucocyte esterase. Fluid leucocyte count, Gram staining, culture, erythrocyte sedimentation rate and C-reactive protein were also assessed. The leucocyte esterase test with a threshold of ++/+++ had a sensitivity of 79.2% (95% CI [confidence interval], 65.9% to 89.2%), specificity of 80.8% (95% CI, 73.3% to 87.1%), positive predictive value (PPV) of 61.8% (95% CI, 49.2% to 73.3%) and negative predictive value (NPV) of 90.1% (95% CI, 84.3% to 95.4%). The leucocyte esterase strip test yielded a high specificity, PPV, NPV, high sensitivity and high diagnostic accuracy. Leucocyte esterase is an accurate, quick and bedside test for septic arthritis and can be used effectively for diagnosing periprosthetic joint infections along with other battery of tests according to the Musculoskeletal Infection Society criteria.

  7. Diagnostic value of scratch-chamber test, skin prick test, histamine release and specific IgE in birch-allergic patients with oral allergy syndrome to apple

    DEFF Research Database (Denmark)

    Osterballe, M; Scheller, R; Stahl Skov, P

    2003-01-01

    BACKGROUND: The aim of the study was to examine the diagnostic value of skin prick test (SPT), scratch-chamber test (SCT), histamine release (HR) and specific immunoglobulin E (IgE) in birch-allergic patients with oral allergy syndrome to apple. METHODS: Ten birch-allergic patients with oral...... with apple and A72 showed a good diagnostic value with a sensitivity of more than 70% and a specificity of 100%. The SCT showed a poor sensitivity to apple, A72 and commercial apple extract. The ML test was not suitable in detecting specific IgE to apple compared with the CAP test. In daily practice...... a detailed case history about symptoms of oral allergy syndrome combined with a SPT with fresh apple peel or A72 will be useful....

  8. Sensitivity analysis for publication bias in meta-analysis of diagnostic studies for a continuous biomarker.

    Science.gov (United States)

    Hattori, Satoshi; Zhou, Xiao-Hua

    2018-02-10

    Publication bias is one of the most important issues in meta-analysis. For standard meta-analyses to examine intervention effects, the funnel plot and the trim-and-fill method are simple and widely used techniques for assessing and adjusting for the influence of publication bias, respectively. However, their use may be subjective and can then produce misleading insights. To make a more objective inference for publication bias, various sensitivity analysis methods have been proposed, including the Copas selection model. For meta-analysis of diagnostic studies evaluating a continuous biomarker, the summary receiver operating characteristic (sROC) curve is a very useful method in the presence of heterogeneous cutoff values. To our best knowledge, no methods are available for evaluation of influence of publication bias on estimation of the sROC curve. In this paper, we introduce a Copas-type selection model for meta-analysis of diagnostic studies and propose a sensitivity analysis method for publication bias. Our method enables us to assess the influence of publication bias on the estimation of the sROC curve and then judge whether the result of the meta-analysis is sufficiently confident or should be interpreted with much caution. We illustrate our proposed method with real data. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Testing the Robustness of the Diagnostic Overshadowing Bias.

    Science.gov (United States)

    Spengler, Paul M.; And Others

    1990-01-01

    The diagnostic overshadowing bias (tendency for a diagnosis of mental retardation to overshadow a coexisting psychopathological disorder) was examined with 57 rehabilitation counselors. Diagnostic overshadowing was found with individuals with an intelligence quotient (IQ) of 58 but not with those having IQs of 70 to 80. Counselor experience with…

  10. [Joint diagnostic value of four temperature sensation tests in elderly patients with type 2 diabetic peripheral neuropathy].

    Science.gov (United States)

    Guo, Wei; Li, Yun-Ming; Ai, Zhi-Hua; You, Zhi-Qing; Wan, Yong; Cheng, Ying; Lang, Hong-Mei

    2013-07-01

    To explore the joint diagnostic value of four temperature sensation tests in elderly patients with type 2 diabetic peripheral neuropathy. Thermal sensory analyzer-II were applied to measure cool sensation (CS), warm sensation (WS), cold pain sensation (CP)and heat pain sensation (HP) of 308 elderly patients with type 2 diabetes. Logistic regression model was adopted to create the new variable Temp4 from four temperature sensation tests to diagnose type 2 diabetic peripheral neuropathy. The ROC curve analysis was used to determine the best cut-off points of the four temperature sensation and Temp4, and the diagnostic value of it was evaluated. The means of temperature sensation tests of the diabetic peripheral neuropathy (DPN) group were significantly different from those of the non-DPN group (P sensation tests to diagnose the DPN, the sensitivity of WS test was the highest, and the value was 0.710; but the specificity, positive predictive value, negative predictive value, Youden index, diagnostic accuracy and Kappa value of cold sensation test were the highest, and the values were 0.842, 0.746, 0.799, 0.528, 77.92% and 0.535, respectively; the Kappa values of the other three temperature sensation tests were all greater than 0.4 (P sensation tests (P sensation quantitative tests were in good agreementand could be applied to diagnose DPN; the new variable Temp4 could be used for diagnosis of DPN with a higher diagnostic accuracy.

  11. The Value of Naproxen Test as a Diagnostic Method to Differentiate Cause of Fever

    Directory of Open Access Journals (Sweden)

    Omer Coskun

    2012-12-01

    Full Text Available Objective: Fever of whatever etiology still remains a perplexing problem to both clinicians and investigators. Increasingly, its role in connective tissue diseases, malignancies and other inflammatory disorders is slowly supplanting the exclusivity of the symptom to just infectious conditions. This study aims to determine the sensitivity of the naproxen test and the diagnostic value in patients with a prolonged febrile illness. Methods: We evaluated twenty patients had been administered the naproxen test. Fever lysis after or within the time frame of drug administration was interpreted as a infectious or an infectious condition. Results: Infectious diseases etiology was detected at 15 patients. 12 and 3 of them responded to naproxen test at the first and second days respectively. Two of non-infectious etiology patients remained unanswered. Conclusion: This study clearly showed that the naproxen test cannot be relied upon to guide diagnostic decision making in patients with fever unknown origin. [TAF Prev Med Bull 2012; 11(6.000: 779-782

  12. Evidence-Based Assignment of Diagnostic Peritoneal Lavage (DPL Sensitivity in Penetrating Abdominal Trauma

    Directory of Open Access Journals (Sweden)

    M. Sharifi

    2008-02-01

    Full Text Available Background:There are a large number of patients with penetrating abdominal trauma who have normal vital signs and negative abdominal examination when referred to trauma centers. Agreat deal of controversy exists between authorities about screening these patients for emergency explorative laparotomy. Many references have reported more than 90% sensitivity for DPL as a diagnostic method to determine whether intraabdominal injuries were present and emergent laparotomy is indicated or not. This study is for reassignment of this sensitivity according to our own evidence. Methods: All of the patients with abdominal stab wounds and normal vital signs plus negative abdominal examination who were referred to Shohada-e-Tajrish hospital between March 2004 to December 2005, underwent local wound exploration and those confirmed to have peritoneal penetration, underwent emergency laparotomy. In the operating room and prior to surgery, under general anesthesia, DPL was performed. Then DPL results were compared with laparotomy findings and DPL sensitivity was assigned. Results: Of the total number of 34 patients, 8 had a positive DPL and positive laparotomy; 2 had a positive DPL and negative laparotomy; 8 had negative DPL and positive laparotomy, and 16 patients had negative DPL and negative laparotomy. Conclusion: According to our study, DPL sensitivity is much less than mentioned in trauma texts (approximately 50%. So, it is not a valuable tool to discriminate between operative and conservative approaches in penetrating abdominal trauma. We suggest more sensitive modalities. Laparotomy is the most sensitive approach but at the price of a high negative laparotomy rate.

  13. Utilization of noninvasive prenatal testing: impact on referrals for diagnostic testing.

    Science.gov (United States)

    Williams, John; Rad, Steve; Beauchamp, Sarah; Ratousi, Dalar; Subramaniam, Vaishnavi; Farivar, Sayeh; Pisarska, Margareta D

    2015-07-01

    Since the introduction of noninvasive prenatal testing (NIPT), a marked decrease in prenatal diagnostic testing (chorionic villus sampling [CVS] and amniocentesis) has been observed with unknown potential effects on genetic diagnosis of these pregnancies. The purpose of this study was to understand the impact of NIPT on genetics counseling referrals, diagnostic testing with CVS/amniocentesis, and appropriate use of NIPT. A retrospective cohort study was performed on all women referred for genetic counseling and prenatal testing during the 2 years preceding the introduction of NIPT (pre-NIPT) and 2 years following (post-NIPT). The primary outcome was the difference in the number of women referred for genetic counseling and prenatal diagnosis during the pre-NIPT period compared with the post-NIPT period. The secondary outcome was the difference in the number of women referred who were not considered candidates for NIPT between the 2 study periods. There was a statistically significant reduction in the number of referrals for genetic counseling and diagnostic testing in the post-NIPT compared with the pre-NIPT period (2824 vs 3944, P = .001), a reduction of 28.4%. During the post-NIPT period there was a significant reduction in referrals of women who would not be candidates for NIPT (467 pre-NIPT vs 285 post-NIPT, P = .043). In women who had diagnostic testing with CVS during the study period, 32.4% of the aneuploidies identified would not have been detected by NIPT. There was a significant reduction in the number of patients referred for genetic counseling and prenatal diagnosis following the introduction of NIPT. In addition, there was a significant reduction in the number of patients referred for counseling and testing who would not be candidates for NIPT. This suggests that an increasing number of potential patients are being offered NIPT screening instead of diagnostic testing, including those at risk for fetal single gene disorders and aneuploidies not

  14. Broadband Liner Optimization for the Source Diagnostic Test Fan

    Science.gov (United States)

    Nark, Douglas M.; Jones, Michael G.

    2012-01-01

    The broadband component of fan noise has grown in relevance with the utilization of increased bypass ratio and advanced fan designs. Thus, while the attenuation of fan tones remains paramount, the ability to simultaneously reduce broadband fan noise levels has become more appealing. This paper describes a broadband acoustic liner optimization study for the scale model Source Diagnostic Test fan. Specifically, in-duct attenuation predictions with a statistical fan source model are used to obtain optimum impedance spectra over a number of flow conditions for three liner locations in the bypass duct. The predicted optimum impedance information is then used with acoustic liner modeling tools to design liners aimed at producing impedance spectra that most closely match the predicted optimum values. Design selection is based on an acceptance criterion that provides the ability to apply increased weighting to specific frequencies and/or operating conditions. Typical tonal liner designs targeting single frequencies at one operating condition are first produced to provide baseline performance information. These are followed by multiple broadband design approaches culminating in a broadband liner targeting the full range of frequencies and operating conditions. The broadband liner is found to satisfy the optimum impedance objectives much better than the tonal liner designs. In addition, the broadband liner is found to provide better attenuation than the tonal designs over the full range of frequencies and operating conditions considered. Thus, the current study successfully establishes a process for the initial design and evaluation of novel broadband liner concepts for complex engine configurations.

  15. Recent advances in diagnostic testing for gastroesophageal reflux disease.

    Science.gov (United States)

    Naik, Rishi D; Vaezi, Michael F

    2017-06-01

    Gastroesophageal reflux disease (GERD) has a large economic burden with important complications that include esophagitis, Barrett's esophagus, and adenocarcinoma. Despite endoscopy, validated patient questionnaires, and traditional ambulatory pH monitoring, the diagnosis of GERD continues to be challenging. Areas covered: This review will explore the difficulties in diagnosing GERD with a focus on new developments, ranging from basic fundamental changes (histology and immunohistochemistry) to direct patient care (narrow-band imaging, impedance, and response to anti-reflux surgery). We searched PubMed using the noted keywords. We included data from full-text articles published in English. Further relevant articles were identified from the reference lists of review articles. Expert commentary: Important advances in novel parameters in intraluminal impedance monitoring such as baseline impedance monitoring has created some insight into alternative diagnostic strategies in GERD. Recent advances in endoscopic assessment of esophageal epithelial integrity via mucosal impedance measurement is questioning the paradigm of prolonged ambulatory testing for GERD. The future of reflux diagnosis may very well be without the need for currently employed technologies and could be as simple as assessing changes in epithelia integrity as a surrogate marker for GERD. However, future studies must validate such an approach.

  16. Evaluating diagnostic tests for bovine tuberculosis in the southern part of Germany: A latent class analysis.

    Directory of Open Access Journals (Sweden)

    Valerie-Beau Pucken

    Full Text Available Germany has been officially free of bovine tuberculosis since 1996. However, in the last years there has been an increase of bovine tuberculosis cases, particularly in the southern part of Germany, in the Allgäu region. As a consequence a one-time tuberculosis surveillance program was revisited with different premortal and postmortal tests. The aim of this paper was to estimate diagnostic sensitivities and specificities of the different tests used within this surveillance program. In the absence of a perfect test with 100% sensitivity and 100% specificity, thus in the absence of a gold standard, a Bayesian latent class approach with two different datasets was performed. The first dataset included 389 animals, tested with single intra-dermal comparative cervical tuberculin (SICCT test, PCR and pathology; the second dataset contained 175 animals, tested with single intra-dermal cervical tuberculin (SICT test, Bovigam® assay, pathology and culture. Two-way conditional dependencies were considered within the models. Additionally, inter-laboratory agreement (five officially approved laboratories of the Bovigam® assay was assessed with Cohen's kappa test (21 blood samples. The results are given in posterior means and 95% credibility intervals. The specificities of the SICT test, SICCT test, PCR and pathology ranged between 75.8% [68.8-82.2%] and 99.0% [96.8-100%]. The Bovigam® assay stood out with a very low specificity (6.9% [3.6-11.1%], though it had the highest sensitivity (95.7% [91.3-99.2%]. The sensitivities of the SICCT test, PCR, SICT test, pathology and culture varied from 57.8% [48.0-67.6%] to 88.9% [65.5-99.7%]. The prevalences were 19.8% [14.6-26.5%] (three-test dataset and 7.7% [4.2-12.3%] (four-test dataset. Among all pairwise comparisons the highest agreement was 0.62 [0.15-1]. In conclusion, the specificity of the Bovigam® assay and the inter-laboratory agreement were lower than expected.

  17. Ultrasonographic diagnosis of ureteral stones: Accuracy and factors influencing on diagnostic sensitivity

    International Nuclear Information System (INIS)

    Park, Young Mi; Han, Sang Seok; Chang, Seung Kuk; Joo, Sang Hoo; Lee, Jeong Sik; Eun, Choong Ki

    1999-01-01

    To determine the accuracy of ultrasonographic diagnosis in patients with clinically suspected ureteral stones and to evaluate the factors influencing on the diagnostic sensitivity for the detection of ureteral stone. The patients (115 cases) with proven presence or absence of ureteral stones were included in the study. At first, both sided kidney and proximal ureters were examined on each decubitus position and then middle ureters were done if proximal ureters were visualized. On the supine view, distal ureters and UVJ were scanned through the acoustic window of the filled bladder. KUB (20 cases), IVU (62 cases), AGP (7 cases), RGP (3 cases), ESWL (9 cases), CT (9 cases), and patients' history of spontaneous passage of stones (5 cases) were included as confirmation methods. The sensitivity, specificity, and accuracy of the ultrasonographic diagnosis of ureteral stones were calculated and the factors influencing on the sensitivity on the focus of the position and size of ureteral stone, visibility of ureter, the presence or absence of renal stone and hydronephrosis were analyzed. Of 82 cases with proven ureteral stone, 72 cases were revealed on ultrasonography and there was one false positive examination among 33 cases with proven absence of ureteral stone. The overall diagnostic accuracy was 90%. The ultrasonographic detection rates of ureteral stones as correlated with their locations were 83% (24/29), 100% (11/11), 80% (16/20), and 100% (21/21) of each group of proximal, middle, distal ureter, and UVJ stones. Of 61 stones, those as correlated with their sizes, were 82% (37/45) and 94% (15/16) of each group less than 10 mm and more than 11 mm. Those as correlated with the presence or absence of ureteral visualization on ultrasonography were 92% (69/75) and 43% (3/7) of each group. Those as correlated with presence of absence of renal stones were 85% (41/48) and 91% (31/34) of each group. Those as correlated with presence or absence of hydronephrosis were 89% (55

  18. Reliable and sensitive physical testing of elite trapeze sailors

    DEFF Research Database (Denmark)

    Bay, Jonathan; Bojsen-Møller, Jens; Nordsborg, Nikolai Baastrup

    2018-01-01

    It was investigated, if a newly developed discipline specific test for elite-level trapeze sailors is reli-able and sensitive. Furthermore, the physical demands of trapeze sailing were examined. In part 1, nine national team athletes were accustomed to a simulated sailing test, which subsequently...... as peak values were 83.5 ± 11.4% and 89.9 ± 1.7% of max, respectively. In conclusion, the present test is reliable and sensitive, thus providing a sailing specific alternative to traditional physical testing of elite trapeze sailors. Additionally, on-water rac-ing requires moderate aerobic energy...... was completed on four occasions to determine test reliability and sensitivity to manipulations in body-weight. Rope-pulling mean power output (MPO), oxygen consumption (VO2 ), heart rate (HR) and blood lactate values were acquired in all trials. In part 2, six sailors completed on-water racing with concurrent...

  19. Estimating diagnostic test accuracies for Brachyspira hyodysenteriae accounting for the complexities of population structure in food animals.

    Directory of Open Access Journals (Sweden)

    Sonja Hartnack

    Full Text Available For swine dysentery, which is caused by Brachyspira hyodysenteriae infection and is an economically important disease in intensive pig production systems worldwide, a perfect or error-free diagnostic test ("gold standard" is not available. In the absence of a gold standard, Bayesian latent class modelling is a well-established methodology for robust diagnostic test evaluation. In contrast to risk factor studies in food animals, where adjustment for within group correlations is both usual and required for good statistical practice, diagnostic test evaluation studies rarely take such clustering aspects into account, which can result in misleading results. The aim of the present study was to estimate test accuracies of a PCR originally designed for use as a confirmatory test, displaying a high diagnostic specificity, and cultural examination for B. hyodysenteriae. This estimation was conducted based on results of 239 samples from 103 herds originating from routine diagnostic sampling. Using Bayesian latent class modelling comprising of a hierarchical beta-binomial approach (which allowed prevalence across individual herds to vary as herd level random effect, robust estimates for the sensitivities of PCR and culture, as well as for the specificity of PCR, were obtained. The estimated diagnostic sensitivity of PCR (95% CI and culture were 73.2% (62.3; 82.9 and 88.6% (74.9; 99.3, respectively. The estimated specificity of the PCR was 96.2% (90.9; 99.8. For test evaluation studies, a Bayesian latent class approach is well suited for addressing the considerable complexities of population structure in food animals.

  20. Diagnostic utility of microarray testing in pregnancy loss.

    Science.gov (United States)

    Rosenfeld, J A; Tucker, M E; Escobar, L F; Neill, N J; Torchia, B S; McDaniel, L D; Schultz, R A; Chong, K; Chitayat, D

    2015-10-01

    To determine the frequency of clinically significant chromosomal abnormalities identified by chromosomal microarray in pregnancy losses at any gestational age and to compare microarray performance with that of traditional cytogenetic analysis when testing pregnancy losses. Among 535 fetal demise specimens of any gestational age, clinical microarray-based comparative genomic hybridization (aCGH) was performed successfully on 515, and a subset of 107 specimens underwent additional single nucleotide polymorphism (SNP) analysis. Overall, clinically significant abnormalities were identified in 12.8% (64/499) of specimens referred with normal or unknown karyotypes. Detection rates were significantly higher with earlier gestational age. In the subset with normal karyotype, clinically significant abnormalities were identified in 6.9% (20/288). This detection rate did not vary significantly with gestational age, suggesting that, unlike aneuploidy, the contribution of submicroscopic chromosomal abnormalities to fetal demise does not vary with gestational age. In the 107 specimens that underwent aCGH and SNP analysis, seven cases (6.5%) had abnormalities of potential clinical significance detected by the SNP component, including female triploidy. aCGH failed to yield fetal results in 8.3%, which is an improvement over traditional cytogenetic analysis of fetal demise specimens. Both the provision of results in cases in which karyotype fails and the detection of abnormalities in the presence of a normal karyotype demonstrate the increased diagnostic utility of microarray in pregnancy loss. Thus, chromosomal microarray testing is a preferable, robust method of analyzing cases of pregnancy loss to better delineate possible genetic etiologies, regardless of gestational age. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

  1. Rapid diagnostic tests for diagnosing uncomplicated P. falciparum malaria in endemic countries.

    Science.gov (United States)

    Abba, Katharine; Deeks, Jonathan J; Olliaro, Piero; Naing, Cho-Min; Jackson, Sally M; Takwoingi, Yemisi; Donegan, Sarah; Garner, Paul

    2011-07-06

    Rapid diagnostic tests (RDTs) for Plasmodium falciparum malaria use antibodies to detect either HRP-2 antigen or pLDH antigen, and can improve access to diagnostics in developing countries. To assess the diagnostic accuracy of RDTs for detecting P. falciparum parasitaemia in persons living in endemic areas who present to ambulatory healthcare facilities with symptoms suggestive of malaria by type and brand. We undertook a comprehensive search of the following databases: Cochrane Infectious Diseases Group Specialized Register; MEDLINE; EMBASE; MEDION; Science Citation Index; Web of Knowledge; African Index Medicus; LILACS; IndMED; to January 14, 2010. Studies comparing RDTs with a reference standard (microscopy or polymerase chain reaction) in blood samples from a random or consecutive series of patients attending ambulatory health facilities with symptoms suggestive of malaria in P. falciparum endemic areas. For each study, a standard set of data was extracted independently by two authors, using a tailored data extraction form. Comparisons were grouped hierarchically by target antigen, and type and brand of RDT, and combined in meta-analysis where appropriate. We identified 74 unique studies as eligible for this review and categorized them according to the antigens they detected. Types 1 to 3 include HRP-2 (from P. falciparum) either by itself or with other antigens. Types 4 and 5 included pLDH (from P. falciparum) either by itself or with other antigens. In comparisons with microscopy, we identified 71 evaluations of Type 1 tests, eight evaluations of Type 2 tests and five evaluations of Type 3 tests. In meta-analyses, average sensitivities and specificities (95% CI) were 94.8% (93.1% to 96.1%) and 95.2% (93.2% to 96.7%) for Type 1 tests, 96.0% (94.0% to 97.3%) and 95.3% (87.3% to 98.3%) for Type 2 tests, and 99.5% (71.0% to 100.0%) and 90.6% (80.5% to 95.7%) for Type 3 tests, respectively. Overall for HRP-2, the meta-analytical average sensitivity and

  2. Rapid diagnostic tests for diagnosing uncomplicated non-falciparum or Plasmodium vivax malaria in endemic countries

    Science.gov (United States)

    Abba, Katharine; Kirkham, Amanda J; Olliaro, Piero L; Deeks, Jonathan J; Donegan, Sarah; Garner, Paul; Takwoingi, Yemisi

    2014-01-01

    Background In settings where both Plasmodium vivax and Plasmodium falciparum infection cause malaria, rapid diagnostic tests (RDTs) need to distinguish which species is causing the patients' symptoms, as different treatments are required. Older RDTs incorporated two test lines to distinguish malaria due to P. falciparum, from malaria due to any other Plasmodium species (non-falciparum). These RDTs can be classified according to which antibodies they use: Type 2 RDTs use HRP-2 (for P. falciparum) and aldolase (all species); Type 3 RDTs use HRP-2 (for P. falciparum) and pLDH (all species); Type 4 use pLDH (fromP. falciparum) and pLDH (all species). More recently, RDTs have been developed to distinguish P. vivax parasitaemia by utilizing a pLDH antibody specific to P. vivax. Objectives To assess the diagnostic accuracy of RDTs for detecting non-falciparum or P. vivax parasitaemia in people living in malaria-endemic areas who present to ambulatory healthcare facilities with symptoms suggestive of malaria, and to identify which types and brands of commercial test best detect non-falciparum and P. vivax malaria. Search methods We undertook a comprehensive search of the following databases up to 31 December 2013: Cochrane Infectious Diseases Group Specialized Register; MEDLINE; EMBASE; MEDION; Science Citation Index; Web of Knowledge; African Index Medicus; LILACS; and IndMED. Selection criteria Studies comparing RDTs with a reference standard (microscopy or polymerase chain reaction) in blood samples from a random or consecutive series of patients attending ambulatory health facilities with symptoms suggestive of malaria in non-falciparum endemic areas. Data collection and analysis For each study, two review authors independently extracted a standard set of data using a tailored data extraction form. We grouped comparisons by type of RDT (defined by the combinations of antibodies used), and combined in meta-analysis where appropriate. Average sensitivities and

  3. Rapid diagnostic tests for diagnosing uncomplicated non-falciparum or Plasmodium vivax malaria in endemic countries.

    Science.gov (United States)

    Abba, Katharine; Kirkham, Amanda J; Olliaro, Piero L; Deeks, Jonathan J; Donegan, Sarah; Garner, Paul; Takwoingi, Yemisi

    2014-12-18

    In settings where both Plasmodium vivax and Plasmodium falciparum infection cause malaria, rapid diagnostic tests (RDTs) need to distinguish which species is causing the patients' symptoms, as different treatments are required. Older RDTs incorporated two test lines to distinguish malaria due to P. falciparum, from malaria due to any other Plasmodium species (non-falciparum). These RDTs can be classified according to which antibodies they use: Type 2 RDTs use HRP-2 (for P. falciparum) and aldolase (all species); Type 3 RDTs use HRP-2 (for P. falciparum) and pLDH (all species); Type 4 use pLDH (fromP. falciparum) and pLDH (all species).More recently, RDTs have been developed to distinguish P. vivax parasitaemia by utilizing a pLDH antibody specific to P. vivax. To assess the diagnostic accuracy of RDTs for detecting non-falciparum or P. vivax parasitaemia in people living in malaria-endemic areas who present to ambulatory healthcare facilities with symptoms suggestive of malaria, and to identify which types and brands of commercial test best detect non-falciparum and P. vivax malaria. We undertook a comprehensive search of the following databases up to 31 December 2013: Cochrane Infectious Diseases Group Specialized Register; MEDLINE; EMBASE; MEDION; Science Citation Index; Web of Knowledge; African Index Medicus; LILACS; and IndMED. Studies comparing RDTs with a reference standard (microscopy or polymerase chain reaction) in blood samples from a random or consecutive series of patients attending ambulatory health facilities with symptoms suggestive of malaria in non-falciparum endemic areas. For each study, two review authors independently extracted a standard set of data using a tailored data extraction form. We grouped comparisons by type of RDT (defined by the combinations of antibodies used), and combined in meta-analysis where appropriate. Average sensitivities and specificities are presented alongside 95% confidence intervals (95% CI). We included 47 studies

  4. Evaluation of the diagnostic accuracy of prototype rapid tests for human African trypanosomiasis.

    Directory of Open Access Journals (Sweden)

    Jeremy M Sternberg

    2014-12-01

    Full Text Available Diagnosis of human African trypanosomiasis (HAT remains a challenge both for active screening, which is critical in control of the disease, and in the point-of-care scenario where early and accurate diagnosis is essential. Recently, the first field deployment of a lateral flow rapid diagnostic test (RDT for HAT, "SD BIOLINE HAT" has taken place. In this study, we evaluated the performance of "SD BIOLINE HAT" and two new prototype RDTs.The performance of "SD BIOLINE HAT" and 2 prototype RDTs was tested using archived plasma from 250 Trypanosoma brucei gambiense patients, and 250 endemic controls. As well as comparison of the sensitivity and specificity of each device, the performance of individual antigens was assessed and the hypothetical performance of novel antigen combinations extrapolated. Neither of the prototype devices were inferior in sensitivity or specificity to "SD BIOLINE HAT" (sensitivity 0.82±0.01, specificity 0.97±0.01, 95% CI at the 5% margins, while one of the devices (BBI had significantly superior sensitivity (0.88±0.03. Analysis of the performance of individual antigens was used to model new antigen combinations to be explored in development of the next generation of HAT RDTs. The modelling showed that an RDT using two recombinant antigens (rLiTat1.5 and rISG65 would give a performance similar to the best devices in this study, and would also offer the most robust performance under deteriorating field conditions.Both "SD BIOLINE HAT" and the prototype devices performed comparably well to one another and also to the published performance range of the card agglutination test for trypanosomiasis in sensitivity and specificity. The performance of individual antigens enabled us to predict that an all-recombinant antigen RDT can be developed with an accuracy equivalent to " SD BIOLINE HAT." Such an RDT would have advantages in simplified manufacture, lower unit cost and assured reproducibility.

  5. Persistent digestive disorders in the tropics: causative infectious pathogens and reference diagnostic tests

    Directory of Open Access Journals (Sweden)

    Becker Sören L

    2013-01-01

    Full Text Available Abstract Background Persistent digestive disorders account for considerable disease burden in the tropics. Despite advances in understanding acute gastrointestinal infections, important issues concerning epidemiology, diagnosis, treatment and control of most persistent digestive symptomatologies remain to be elucidated. Helminths and intestinal protozoa are considered to play major roles, but the full extent of the aetiologic spectrum is still unclear. We provide an overview of pathogens causing digestive disorders in the tropics and evaluate available reference tests. Methods We searched the literature to identify pathogens that might give rise to persistent diarrhoea, chronic abdominal pain and/or blood in the stool. We reviewed existing laboratory diagnostic methods for each pathogen and stratified them by (i microscopy; (ii culture techniques; (iii immunological tests; and (iv molecular methods. Pathogen-specific reference tests providing highest diagnostic accuracy are described in greater detail. Results Over 30 pathogens may cause persistent digestive disorders. Bacteria, viruses and parasites are important aetiologic agents of acute and long-lasting symptomatologies. An integrated approach, consisting of stool culture, microscopy and/or specific immunological techniques for toxin, antigen and antibody detection, is required for accurate diagnosis of bacteria and parasites. Molecular techniques are essential for sensitive diagnosis of many viruses, bacteria and intestinal protozoa, and are increasingly utilised as adjuncts for helminth identification. Conclusions Diagnosis of the broad spectrum of intestinal pathogens is often cumbersome. There is a need for rapid diagnostic tests that are simple and affordable for resource-constrained settings, so that the management of patients suffering from persistent digestive disorders can be improved.

  6. Cost-effectiveness analysis of introducing malaria diagnostic testing in drug shops

    DEFF Research Database (Denmark)

    Hansen, Kristian Schultz; Clarke, Siân E.; Lal, Sham

    2017-01-01

    to correct diagnosis. The present study was a cost-effectiveness analysis of the introduction of mRDTs in Ugandan drug shops. Methods Drug shop vendors were trained to perform and sell subsidised mRDTs and artemisinin-based combination therapies (ACTs) in the intervention arm while vendors offered ACTs...... of malaria, resulting in low incremental costs for the health sector at US $0.55 per patient appropriately treated of malaria. High expenditure on non-ACT drugs by households contributed to higher incremental societal costs of US$3.83. Sensitivity analysis showed that mRDTs would become less cost......Background Private sector drug shops are an important source of malaria treatment in Africa, yet diagnosis without parasitological testing is common among these providers. Accurate rapid diagnostic tests for malaria (mRDTs) require limited training and present an opportunity to increase access...

  7. How diagnostic tests help to disentangle the mechanisms underlying neuropathic pain symptoms in painful neuropathies.

    Science.gov (United States)

    Truini, Andrea; Cruccu, Giorgio

    2016-02-01

    Neuropathic pain, ie, pain arising directly from a lesion or disease affecting the somatosensory afferent pathway, manifests with various symptoms, the commonest being ongoing burning pain, electrical shock-like sensations, and dynamic mechanical allodynia. Reliable insights into the mechanisms underlying neuropathic pain symptoms come from diagnostic tests documenting and quantifying somatosensory afferent pathway damage in patients with painful neuropathies. Neurophysiological investigation and skin biopsy studies suggest that ongoing burning pain primarily reflects spontaneous activity in nociceptive-fiber pathways. Electrical shock-like sensations presumably arise from high-frequency ectopic bursts generated in demyelinated, nonnociceptive, Aβ fibers. Although the mechanisms underlying dynamic mechanical allodynia remain debatable, normally innocuous stimuli might cause pain by activating spared and sensitized nociceptive afferents. Extending the mechanistic approach to neuropathic pain symptoms might advance targeted therapy for the individual patient and improve testing for new drugs.

  8. The sensitivity of the bielschowsky head-tilt test in diagnosing acquired bilateral superior oblique paresis.

    Science.gov (United States)

    Muthusamy, Brinda; Irsch, Kristina; Peggy Chang, Han-Ying; Guyton, David L

    2014-04-01

    To determine the sensitivity of the Bielschowsky head-tilt test and other commonly used criteria in identifying patients with true bilateral superior oblique paresis. A retrospective chart review was performed to identify patients seen between 1978 and 2009 who were diagnosed with acquired bilateral superior oblique paresis. All patients had a confirmed history of head trauma or brain surgery with altered consciousness followed by symptomatic diplopia. Bilateral superior oblique paresis was defined and diagnosed by the above history, including the presence of greater extorsion in downgaze than upgaze on Lancaster red-green testing, a V-pattern strabismus, and bilateral fundus extorsion. We analyzed findings of the Bielschowsky head-tilt test, the Parks 3-step test, and reversal of the hypertropia from straight-ahead gaze to the other 8 diagnostic positions of gaze to determine these tests' sensitivity in identifying true bilateral superior oblique paresis. Twenty-five patients were identified with the diagnosis of true bilateral superior oblique paresis. The Bielschowsky head-tilt test had a 40% sensitivity, the Parks 3-step test had a sensitivity of 24%, and reversal of the hypertropia had a sensitivity of 60% in making the diagnosis of true bilateral superior oblique paresis. What previously has been described as masked bilateral superior oblique paresis simply may be a reflection of inherent poor sensitivity of the Bielschowsky head-tilt test, the Parks 3-step test, and reversal of the hypertropia in diagnosing bilateral superior oblique paresis. Hence, none of these tests should be relied on exclusively to make this diagnosis. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Diagnostic accuracy of point-of-care tests for hepatitis C virus infection: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Mehnaaz Sultan Khuroo

    Full Text Available Point-of-care tests provide a plausible diagnostic strategy for hepatitis C infection in economically impoverished areas. However, their utility depends upon the overall performance of individual tests.A literature search was conducted using the metasearch engine Mettā, a query interface for retrieving articles from five leading medical databases. Studies were included if they employed point-of-care tests to detect antibodies of hepatitis C virus and compared the results with reference tests. Two reviewers performed a quality assessment of the studies and extracted data for estimating test accuracy.Thirty studies that had evaluated 30 tests fulfilled the inclusion criteria. The overall pooled sensitivity, specificity, positive likelihood-ratio, negative likelihood-ratio and diagnostic odds ratio for all tests were 97.4% (95% CI: 95.9-98.4, 99.5% (99.2-99.7, 80.17 (55.35-116.14, 0.03 (0.02-0.04, and 3032.85 (1595.86-5763.78, respectively. This suggested a high pooled accuracy for all studies. We found substantial heterogeneity between studies, but none of the subgroups investigated could account for the heterogeneity. Genotype diversity of HCV had no or minimal influence on test performance. Of the seven tests evaluated in the meta-regression model, OraQuick had the highest test sensitivity and specificity and showed better performance than a third generation enzyme immunoassay in seroconversion panels. The next highest test sensitivities and specificities were from TriDot and SDBioline, followed by Genedia and Chembio. The Spot and Multiplo tests produced poor test sensitivities but high test specificities. Nine of the remaining 23 tests produced poor test sensitivities and specificities and/or showed poor performances in seroconversion panels, while 14 tests had high test performances with diagnostic odds ratios ranging from 590.70 to 28822.20.Performances varied widely among individual point-of-care tests for diagnosis of hepatitis C virus

  10. Prevalence of tick-borne haemoparasites in small ruminants in Turkey and diagnostic sensitivity of single-PCR and RLB.

    Science.gov (United States)

    Bilgic, Huseyin Bilgin; Bakırcı, Serkan; Kose, Onur; Unlu, Ahmet Hakan; Hacılarlıoglu, Selin; Eren, Hasan; Weir, William; Karagenc, Tulin

    2017-04-27

    Tick-borne haemoparasitic diseases (TBHDs), caused by Theileria, Babesia, Anaplasma and Ehrlichia, are common in regions of the world where the distributions of host, pathogen and vector overlap. Many of these diseases threaten livestock production and some also represent a concern to human public health. The primary aim of this study was to determine the prevalence of the above-mentioned pathogens in a large number of blood samples (n = 1979) collected from sheep (n = 1727) and goats (n = 252) in Turkey. A secondary aim was to assess the diagnostic sensitivity of a number of species-specific polymerase chain reaction (PCR) tests and the reverse line blotting (RLB) assay. DNA samples were screened using species-specific PCR for the presence of Theileria ovis, Theileria sp. MK, T. lestoquardi, T. uilenbergi, T. luwenshuni, Babesia ovis, Anaplasma ovis and A. phagocytophilum while RLB was undertaken to test for the presence of all known Theileria, Babesia, Anaplasma and Ehrlichia species. The diagnostic sensitivity of these two approaches was then compared in terms of their ability to detect single species and mixed infections. Overall, 84 and 74.43% of the small ruminants sampled were identified as hosting one or more pathogen(s) by species-specific PCR and RLB respectively. The presence of Theileria sp. OT1, T. luwenshuni and T. uilenbergi in Turkey was revealed for the first time while the presence of Babesia motasi, B. crassa and T. separata in Turkish small ruminants was confirmed using molecular methods. A high prevalence of mixed infection was evident, with PCR and RLB approaches indicating that 52.24 and 35.42% of animals were co-infected with multiple species, respectively. More than 80% of the mixed infections contained T. ovis and/or A. ovis. The RLB approach was found to be capable of detecting mixed infections with species such as Theileria sp. OT1, Theileria sp. OT3, T. separata, B. crassa and Babesia spp. The results indicated that

  11. Synthesis of evidence of diagnostic tests and preventive programs identifying pre-diabetes type

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    Dagmar Tučková

    2015-09-01

    Full Text Available Introduction: Type 2 diabetes mellitus (T2D has become the main type of diabetes in children and it is expected that in countries with high income diabetes it is projected to be one of the leading causes of death by 2030. Another fact is that programs and tests diagnosing pre-diabetes type 2 (T2P-DMC are missing. Methods: The aim of the paper is to present the steps for the synthesis of the evidence within the brand new type of the systematic review (SR: SR of diagnostic test accuracy (DTA. Using the acronym PIRD it was developed a review question, search strategy and inclusion and exclusion criteria. Results: The initial search was done in two databases (MedLine and Cinahl with 2 025 results. The second search after the improvement of the sensitivity and the specificity was done in 15 databases with 3 681 results. Conclusion: This methodological paper introduces how to conduct the systematic review protocols of diagnostic test accuracy on the example of T2P-DMC.

  12. Diagnostics

    DEFF Research Database (Denmark)

    Donné, A.J.H.; Costley, A.E.; Barnsley, R.

    2007-01-01

    In order to support the operation of ITER and the planned experimental programme an extensive set of plasma and first wall measurements will be required. The number and type of required measurements will be similar to those made on the present-day large tokamaks while the specification...... of the measurements—time and spatial resolutions, etc—will in some cases be more stringent. Many of the measurements will be used in the real time control of the plasma driving a requirement for very high reliability in the systems (diagnostics) that provide the measurements. The implementation of diagnostic systems......&D is needed to prepare the systems. In some cases the environmental difficulties are so severe that new diagnostic techniques are required. The starting point in the development of diagnostics for ITER is to define the measurement requirements and develop their justification. It is necessary to include all...

  13. Advances in techniques of testing mycobacterial drug sensitivity, and the use of sensitivity tests in tuberculosis control programmes

    Science.gov (United States)

    Canetti, G.; Fox, Wallace; Khomenko, A.; Mahler, H. T.; Menon, N. K.; Mitchison, D. A.; Rist, N.; Šmelev, N. A.

    1969-01-01

    In a paper arising out of an informal international consultation of specialists in the bacteriology of tuberculosis held in 1961, an attempt was made to formulate criteria, and specify technical procedures, for reliable tests of sensitivity (the absolute-concentration method, the resistance-ratio method and the proportion method) to the 3 main antituberculosis drugs (isoniazid, streptomycin and p-aminosalicylic acid). Seven years later, a further consultation was held to review the latest developments in the field and to suggest how sensitivity tests might be put to practical use in tuberculosis control programmes. The participants reached agreement on how to define drug sensitivity and resistance, and stressed the importance of using a discrimination approach to the calibration of sensitivity tests. Their views are contained in the present paper, which also includes descriptions of the sensitivity tests used by the Medical Research Council of Great Britain for first- and second-line drugs (minimal inhibitory concentration and resistance-ratio methods), the two main variants of the proportion method developed by the Institut Pasteur, Paris, and a method for calibrating sensitivity tests. PMID:5309084

  14. Development, Evaluation, and Integration of a Quantitative Reverse-Transcription Polymerase Chain Reaction Diagnostic Test for Ebola Virus on a Molecular Diagnostics Platform.

    Science.gov (United States)

    Cnops, Lieselotte; Van den Eede, Peter; Pettitt, James; Heyndrickx, Leo; De Smet, Birgit; Coppens, Sandra; Andries, Ilse; Pattery, Theresa; Van Hove, Luc; Meersseman, Geert; Van Den Herrewegen, Sari; Vergauwe, Nicolas; Thijs, Rein; Jahrling, Peter B; Nauwelaers, David; Ariën, Kevin K

    2016-10-15

     The 2013-2016 Ebola epidemic in West Africa resulted in accelerated development of rapid diagnostic tests for emergency outbreak preparedness. We describe the development and evaluation of the Idylla™ prototype Ebola virus test, a fully automated sample-to-result molecular diagnostic test for rapid detection of Zaire ebolavirus (EBOV) and Sudan ebolavirus (SUDV).  The Idylla™ prototype Ebola virus test can simultaneously detect EBOV and SUDV in 200 µL of whole blood. The sample is directly added to a disposable cartridge containing all reagents for sample preparation, RNA extraction, and amplification by reverse-transcription polymerase chain reaction analysis. The performance was evaluated with a variety of sample types, including synthetic constructs and whole blood samples from healthy volunteers spiked with viral RNA, inactivated virus, and infectious virus.  The 95% limits of detection for EBOV and SUDV were 465 plaque-forming units (PFU)/mL (1010 copies/mL) and 324 PFU/mL (8204 copies/mL), respectively. In silico and in vitro analyses demonstrated 100% correct reactivity for EBOV and SUDV and no cross-reactivity with relevant pathogens. The diagnostic sensitivity was 97.4% (for EBOV) and 91.7% (for SUDV), the specificity was 100%, and the diagnostic accuracy was 95.9%.  The Idylla™ prototype Ebola virus test is a fast, safe, easy-to-use, and near-patient test that meets the performance criteria to detect EBOV in patients with suspected Ebola. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  15. Diagnostic Value of the Cobalt ({sup 58}Co) Excretion Test in Iron Deficiency Anemia

    Energy Technology Data Exchange (ETDEWEB)

    Sihn, Hyun Chung; Hong, Kee Suck; Cho, Kyung Sam; Song, In Kyung; Koh, Chang Soon; Lee, Mun Ho [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1976-03-15

    The diagnosis of iron deficiency rests upon the correct evaluation of body iron stores. Morphological interpretation of blood film and the red cell indices are not reliable and often absent in mild iron deficiency. Serum iron levels and iron-binding capacity are more sensitive indices of iron deficiency, but they are often normal in iron depletion and mild iron deficiency anemia. They are also subject ro many variables which may introduce substantial errors and influenced by many pathologic and physiologic states. Examination of the bone marrow aspirate for stainable iron has been regarded as one of the most sensitive and reliable diagnostic method for detecting iron deficiency, but this also has limitations. Thus, there is still need for a more practical, but sensitive and reliable substitute as a screening test of iron deficiency. Pollack et al. (1965) observed that the intestinal absorption of cobalt was raised in iron, deficient rats and Valberg et al. (1969) found that cobalt absorption was elevated in patients with iron deficiency. A direct correlation was demonstrated between the amounts of radioiron and radiocobalt absorbed. Unlike iron, excess cobalt was excreted by the kidney, the percentage of radioactivity in the urine being directly related to the percentage absorbed from the gastro-intestinal tract. Recently a test based on the urinary excretion of an oral dose of {sup 57}Co has been proposed as a method for detecting iron deficiency. To assess the diagnostic value of urinary cobalt excretion test cobaltous chloride labelled with 1 muCi of {sup 58}Co was given by mouth and the percentage of the test dose excreted in the urine was measured by a gamma counter. The mean 24 hour urinary cobalt excretion in control subjects with normal iron stores was 6.1%(1.9-15.2%). Cobalt excretion was markedly increased in patients with iron deficiency and excreted more than 29% of the dose. In contrast, patients with anemia due to causes other than iron deficiency

  16. Diagnostic Value of the Cobalt (58Co) Excretion Test in Iron Deficiency Anemia

    International Nuclear Information System (INIS)

    Sihn, Hyun Chung; Hong, Kee Suck; Cho, Kyung Sam; Song, In Kyung; Koh, Chang Soon; Lee, Mun Ho

    1976-01-01

    The diagnosis of iron deficiency rests upon the correct evaluation of body iron stores. Morphological interpretation of blood film and the red cell indices are not reliable and often absent in mild iron deficiency. Serum iron levels and iron-binding capacity are more sensitive indices of iron deficiency, but they are often normal in iron depletion and mild iron deficiency anemia. They are also subject ro many variables which may introduce substantial errors and influenced by many pathologic and physiologic states. Examination of the bone marrow aspirate for stainable iron has been regarded as one of the most sensitive and reliable diagnostic method for detecting iron deficiency, but this also has limitations. Thus, there is still need for a more practical, but sensitive and reliable substitute as a screening test of iron deficiency. Pollack et al. (1965) observed that the intestinal absorption of cobalt was raised in iron, deficient rats and Valberg et al. (1969) found that cobalt absorption was elevated in patients with iron deficiency. A direct correlation was demonstrated between the amounts of radioiron and radiocobalt absorbed. Unlike iron, excess cobalt was excreted by the kidney, the percentage of radioactivity in the urine being directly related to the percentage absorbed from the gastro-intestinal tract. Recently a test based on the urinary excretion of an oral dose of 57 Co has been proposed as a method for detecting iron deficiency. To assess the diagnostic value of urinary cobalt excretion test cobaltous chloride labelled with 1 μCi of 58 Co was given by mouth and the percentage of the test dose excreted in the urine was measured by a gamma counter. The mean 24 hour urinary cobalt excretion in control subjects with normal iron stores was 6.1%(1.9-15.2%). Cobalt excretion was markedly increased in patients with iron deficiency and excreted more than 29% of the dose. In contrast, patients with anemia due to causes other than iron deficiency excreted less

  17. Modelling multiple thresholds in meta-analysis of diagnostic test accuracy studies

    Directory of Open Access Journals (Sweden)

    Susanne Steinhauser

    2016-08-01

    Full Text Available Abstract Background In meta-analyses of diagnostic test accuracy, routinely only one pair of sensitivity and specificity per study is used. However, for tests based on a biomarker or a questionnaire often more than one threshold and the corresponding values of true positives, true negatives, false positives and false negatives are known. Methods We present a new meta-analysis approach using this additional information. It is based on the idea of estimating the distribution functions of the underlying biomarker or questionnaire within the non-diseased and diseased individuals. Assuming a normal or logistic distribution, we estimate the distribution parameters in both groups applying a linear mixed effects model to the transformed data. The model accounts for across-study heterogeneity and dependence of sensitivity and specificity. In addition, a simulation study is presented. Results We obtain a summary receiver operating characteristic (SROC curve as well as the pooled sensitivity and specificity at every specific threshold. Furthermore, the determination of an optimal threshold across studies is possible through maximization of the Youden index. We demonstrate our approach using two meta-analyses of B type natriuretic peptide in heart failure and procalcitonin as a marker for sepsis. Conclusions Our approach uses all the available information and results in an estimation not only of the performance of the biomarker but also of the threshold at which the optimal performance can be expected.

  18. Evaluation of diagnostic tests for cytomegalovirus active infection in renal transplant recipients

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    Rodrigo Fontanive Franco

    Full Text Available Abstract Introduction: Cytomegalovirus (CMV infection is a main viral infection after kidney transplantation. The diagnostic methods currently employed are pp65 antigenemia and nucleic acid amplification by polymerase chain reaction (PCR and aim at detecting viral replication. Objective: The goal of this study was to evaluate and compare by both methods the incidence of CMV active infection in kidney transplant patients and to establishthe best clinical-laboratory correlation. Methods: Thirty sequential kidney transplant recipients were enrolled in a single center prospective cohort study. Peripheral blood samples were drawn from day 15 until the 6th month after transplantation and tested for CMV replication by pp65 antigenemia and quantitative PCR assays (qPCR. Results: Two hundred forty samples were analyzed and the incidence of active infection was similar by both methods. Time elapsed to the first positive test was almost identical but more samples tested positive by qPCR than by antigenemia in a behavior that was almost evenly distributed overtime. Agreement between tests was observed in 217 samples (90.4%; kappa = 0.529; p < 0.001 and in 25 patients the tests were concordant (83.3%; kappa = 0.667; p < 0.001. The evaluation of the diagnostic parameters for CMV replication revealed higher sensitivity for the qPCR test (82.1% against antigenemia (59.0%. Quantitative PCR was also slightly more accurate than antigenemia. Conclusion: Our data demonstrate that both methods are suitable and have almost equivalent accuracy for the detection of post-transplant cytomegalovirus replication. The choice for either test must take in consideration the demand, execution capability and cost-effectiveness at each institution.

  19. Diagnostic Value of ELISA Tests for the Detection of Specific Antibodies in Cats and Rabbits with Dermatophytosis

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    Marinka Drobnič-Košorok

    2002-01-01

    Full Text Available Two indirect ELISA tests developed for the detection of specific IgG in cats and rabbits, infected with M. canis and T. mentagrophytes, respectively, were evaluated and compared. The levels of specific antibodies were determined in sera of 20 cats and 25 rabbits naturally infected with M. canis and T. mentagrophytes, respectively. Infection was confirmed by the results of fungal culture. Blood samples from 12 cats and 17 rabbits, previously unexposed to dermatophytes, served as negative controls. A significant increase in the level of specific antibodies in groups of infected animals was demonstrated. Sensitivity, specificity and predictive values of a positive and a negative test were determined to evaluate the diagnostic potential. ELISA for the detection of specific antibodies in cats infected with M. canis (ELISA-cats test exhibited 75.0 % of sensitivity at 91.7 % of specificity, whereas the test for the detection of specific antibodies in rabbits, infected with T. mentagrophytes (ELISA-rabbits test is highly sensitive (96.0 % and highly specific (94.1 %, confirming its encouraging diagnostic potential. The cross-reactivity of fungal antigens was tested by performing the assays with antigens M. canis, T. mentagrophytes, M. pachydermatis and A. fumigatus. There were no significant indications of cross-reactions in the test T. mentagrophytes-rabbits, whereas strong cross-reaction between dermatophyte antigens was observed in the test M. canis-cats.

  20. Diagnostic and prognostic value of high-sensitivity cardiac troponin T in patients with syncope.

    Science.gov (United States)

    Christ, Michael; Geier, Felicitas; Popp, Steffen; Singler, Katrin; Smolarsky, Alexander; Bertsch, Thomas; Müller, Christian; Greve, Yvonne

    2015-02-01

    We examined the diagnostic and predictive value of high-sensitivity cardiac troponin T (cTnThs) in patients with syncope. We performed an analysis of consecutive patients with syncope presenting to the emergency department. The primary end point was the accuracy to diagnose a cardiac syncope. In addition, the study explored the prognostic relevance of cTnThs in patients with cardiac and noncardiac syncope. A total of 360 patients were enrolled (median age, 70.5 years; male, 55.8%; 23.9% aged >80 years). Cardiac syncope was present in 22% of patients, reflex syncope was present in 40% of patients, syncope due to orthostatic hypotension was present in 20% of patients, and unexplained syncope was present in 17.5% of patients. A total of 148 patients (41%) had cTnThs levels above the 99% confidence interval (CI) (cutoff point). The diagnostic accuracy for cTnThs levels to determine the diagnosis of cardiac syncope was quantified by the area under the curve (0.77; CI, 0.72-0.83; P value of cTnThs levels within 30 days: Patients with increased cTnThs levels had a 52% likelihood for adverse events, patients with cTnThs levels below the cutoff point had a low risk (negative predictive value, 83.5%). Increased cTnThs levels indicate adverse prognosis in patients with noncardiac causes of syncope, but not in patients with cardiac syncope being a risk factor for adverse outcome by itself. Patients with syncope presenting to the emergency department have a high proportion of life-threatening conditions. cTnThs levels show a limited diagnostic and predictive accuracy for the identification of patients with syncope at high risk. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Meta-analysis for the comparison of two diagnostic tests to a common gold standard: A generalized linear mixed model approach.

    Science.gov (United States)

    Hoyer, Annika; Kuss, Oliver

    2016-08-02

    Meta-analysis of diagnostic studies is still a rapidly developing area of biostatistical research. Especially, there is an increasing interest in methods to compare different diagnostic tests to a common gold standard. Restricting to the case of two diagnostic tests, in these meta-analyses the parameters of interest are the differences of sensitivities and specificities (with their corresponding confidence intervals) between the two diagnostic tests while accounting for the various associations across single studies and between the two tests. We propose statistical models with a quadrivariate response (where sensitivity of test 1, specificity of test 1, sensitivity of test 2, and specificity of test 2 are the four responses) as a sensible approach to this task. Using a quadrivariate generalized linear mixed model naturally generalizes the common standard bivariate model of meta-analysis for a single diagnostic test. If information on several thresholds of the tests is available, the quadrivariate model can be further generalized to yield a comparison of full receiver operating characteristic (ROC) curves. We illustrate our model by an example where two screening methods for the diagnosis of type 2 diabetes are compared. © The Author(s) 2016.

  2. A diagnostic flow chart for POLG-related diseases based on signs sensitivity and specificity.

    Science.gov (United States)

    Tchikviladzé, Maya; Gilleron, Mylène; Maisonobe, Thierry; Galanaud, Damien; Laforêt, Pascal; Durr, Alexandra; Eymard, Bruno; Mochel, Fanny; Ogier, Hélène; Béhin, Anthony; Stojkovic, Tanya; Degos, Bertrand; Gourfinkel-An, Isabelle; Sedel, Frederic; Anheim, Mathieu; Elbaz, Alexis; Viala, Karine; Vidailhet, Marie; Brice, Alexis; Jardel, Claude; Lombès, Anne

    2015-06-01

    Diseases due to mutations of POLG gene, encoding the mitochondrial DNA polymerase, are reputed to have very diverse clinical presentations and have been proposed to cause up to 25% adult mitochondrial diseases. Our objective was the evaluation of the specificity and sensitivity of the signs encountered with POLG mutations. Forty-four patients out of 154 with sequenced POLG gene had mutations affecting either one (POLG(+/-) group) or two POLG alleles (POLG(+/+) group). Phenotyping included clinical signs, electroneuromyography and brain imaging while mitochondrial investigations encompassed muscle histochemistry, respiratory chain assays and search for multiple mitochondrial deletions. The specificity and sensitivity of the signs associated with POLG mutations were analysed by comparison between POLG(+/+) and patients without POLG mutation. High sensitivity but low specificity was observed with single signs such as axonal sensory neuropathy, cerebellar syndrome, movement disorders and weakness involving ocular, pharyngeal, axial and/or limb muscles. Specificity was increased with combination of previous signs plus psychiatric symptoms, cognitive impairment and epilepsy. High specificity and sensitivity was only obtained with sensory neuronopathy associated with one of the following signs: weakness of ocular, pharyngeal, axial and/or limb muscles. Mitochondrial investigations did not suffice for diagnosis. The widespread neuromuscular signs were often present since disease onset and were the rule above 50 years of age leading to a very low probability of POLG mutations in patients with less than three signs and absent sensory neuropathy. Phenotypes associated with POLG mutations follow a reproducible pattern, which allows establishing a diagnostic flow chart. 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.

  3. The sensitivity of patch test in patients with psoriasis

    Directory of Open Access Journals (Sweden)

    Yavuz Yeşilova

    2010-09-01

    Full Text Available Objectives: Allergic diseases play an important role in the natural course of psoriasis. Atopic sensitization and con-tact dermatitis are common in patients with psoriasis. Since the symptoms are prolonged in patients who are resistant to therapy and exposure to itchy and external factors are common among these patients, the effects of contact aller-gens on triggering psoriasis are investigated. Contact allergens have an important role in activation and remission of psoriasis. We aimed to investigate contact sensitization rates in patients with psoriasis in the study.Material and Methods: Contact sensitization was investigated with the application of European standard series in twenty patients with psoriasis, twenty patients with contact dermatitis, and twenty healthy persons. Results: Among the whole study cases, positivity rate of patch test against one allergen at least was 25%. rate of patch test was 25% in patients with psoriasis, 35% in patients with contact dermatitis, and 15% in healthy persons. There were no significant differences between the groups according to sensitization to one or more allergens (p>0.05. There were no significant difference in clinical subgroup of psoriatic patients according to contact sensitiza-tion (p>0.05. The allergens in patients with psoriasis on patch test were as the followings: phenyldiamine, potassium dichromat, nickel, and cobalt.Conclusion: We think that the patch test has a major role in the diagnosis and elimination of allergens in patients with the chronic and resistant diseases and palmoplantar and flexural psoriasis.

  4. Bench-top validation testing of selected immunological and molecular Renibacterium salmoninarum diagnostic assays by comparison with quantitative bacteriological culture

    Science.gov (United States)

    Elliott, D.G.; Applegate, L.J.; Murray, A.L.; Purcell, M.K.; McKibben, C.L.

    2013-01-01

    No gold standard assay exhibiting error-free classification of results has been identified for detection of Renibacterium salmoninarum, the causative agent of salmonid bacterial kidney disease. Validation of diagnostic assays for R. salmoninarum has been hindered by its unique characteristics and biology, and difficulties in locating suitable populations of reference test animals. Infection status of fish in test populations is often unknown, and it is commonly assumed that the assay yielding the most positive results has the highest diagnostic accuracy, without consideration of misclassification of results. In this research, quantification of R. salmoninarum in samples by bacteriological culture provided a standardized measure of viable bacteria to evaluate analytical performance characteristics (sensitivity, specificity and repeatability) of non-culture assays in three matrices (phosphate-buffered saline, ovarian fluid and kidney tissue). Non-culture assays included polyclonal enzyme-linked immunosorbent assay (ELISA), direct smear fluorescent antibody technique (FAT), membrane-filtration FAT, nested polymerase chain reaction (nested PCR) and three real-time quantitative PCR assays. Injection challenge of specific pathogen-free Chinook salmon, Oncorhynchus tshawytscha (Walbaum), with R. salmoninarum was used to estimate diagnostic sensitivity and specificity. Results did not identify a single assay demonstrating the highest analytical and diagnostic performance characteristics, but revealed strengths and weaknesses of each test.

  5. Impact of imperfect test sensitivity on determining risk factors: the case of bovine tuberculosis.

    Science.gov (United States)

    Szmaragd, Camille; Green, Laura E; Medley, Graham F; Browne, William J

    2012-01-01

    Imperfect diagnostic testing reduces the power to detect significant predictors in classical cross-sectional studies. Assuming that the misclassification in diagnosis is random this can be dealt with by increasing the sample size of a study. However, the effects of imperfect tests in longitudinal data analyses are not as straightforward to anticipate, especially if the outcome of the test influences behaviour. The aim of this paper is to investigate the impact of imperfect test sensitivity on the determination of predictor variables in a longitudinal study. To deal with imperfect test sensitivity affecting the response variable, we transformed the observed response variable into a set of possible temporal patterns of true disease status, whose prior probability was a function of the test sensitivity. We fitted a Bayesian discrete time survival model using an MCMC algorithm that treats the true response patterns as unknown parameters in the model. We applied our approach to epidemiological data of bovine tuberculosis outbreaks in England and investigated the effect of reduced test sensitivity in the determination of risk factors for the disease. We found that reduced test sensitivity led to changes to the collection of risk factors associated with the probability of an outbreak that were chosen in the 'best' model and to an increase in the uncertainty surrounding the parameter estimates for a model with a fixed set of risk factors that were associated with the response variable. We propose a novel algorithm to fit discrete survival models for longitudinal data where values of the response variable are uncertain. When analysing longitudinal data, uncertainty surrounding the response variable will affect the significance of the predictors and should therefore be accounted for either at the design stage by increasing the sample size or at the post analysis stage by conducting appropriate sensitivity analyses.

  6. Impact of imperfect test sensitivity on determining risk factors: the case of bovine tuberculosis.

    Directory of Open Access Journals (Sweden)

    Camille Szmaragd

    Full Text Available BACKGROUND: Imperfect diagnostic testing reduces the power to detect significant predictors in classical cross-sectional studies. Assuming that the misclassification in diagnosis is random this can be dealt with by increasing the sample size of a study. However, the effects of imperfect tests in longitudinal data analyses are not as straightforward to anticipate, especially if the outcome of the test influences behaviour. The aim of this paper is to investigate the impact of imperfect test sensitivity on the determination of predictor variables in a longitudinal study. METHODOLOGY/PRINCIPAL FINDINGS: To deal with imperfect test sensitivity affecting the response variable, we transformed the observed response variable into a set of possible temporal patterns of true disease status, whose prior probability was a function of the test sensitivity. We fitted a Bayesian discrete time survival model using an MCMC algorithm that treats the true response patterns as unknown parameters in the model. We applied our approach to epidemiological data of bovine tuberculosis outbreaks in England and investigated the effect of reduced test sensitivity in the determination of risk factors for the disease. We found that reduced test sensitivity led to changes to the collection of risk factors associated with the probability of an outbreak that were chosen in the 'best' model and to an increase in the uncertainty surrounding the parameter estimates for a model with a fixed set of risk factors that were associated with the response variable. CONCLUSIONS/SIGNIFICANCE: We propose a novel algorithm to fit discrete survival models for longitudinal data where values of the response variable are uncertain. When analysing longitudinal data, uncertainty surrounding the response variable will affect the significance of the predictors and should therefore be accounted for either at the design stage by increasing the sample size or at the post analysis stage by conducting

  7. "Shotgun" versus sequential testing. Cost-effectiveness of diagnostic strategies for vaginitis.

    Science.gov (United States)

    Carr, Phyllis L; Rothberg, Michael B; Friedman, Robert H; Felsenstein, Donna; Pliskin, Joseph S

    2005-09-01

    Although vaginitis is a common outpatient problem, only 60% of patients can be diagnosed at the initial office visit of a primary care provider using the office procedures of pH testing, whiff tests, normal saline, and potassium hydroxide preps. To determine the most cost-effective diagnostic and treatment approach for the medical management of vaginitis. Decision and cost-effectiveness analyses. Healthy women with symptoms of vaginitis undiagnosed after an initial pelvic exam, wet mount preparations, pH, and the four criteria to diagnose bacterial vaginosis. General office practice. We evaluated 28 diagnostic strategies comprised of combinations of pH testing, vaginal cultures for yeast and Trichomonas vaginalis, Gram's stain for bacterial vaginosis, and DNA probes for Neisseria gonorrhoeae and Chlamydia. Data sources for the study were confined to English language literature. The outcome measures were symptom-days and costs. The least expensive strategy was to perform yeast culture, gonorrhoeae and Chlamydia probes at the initial visit, and Gram's stain and Trichomonas culture only when the vaginal pH exceeded 4.9 (330 dollars, 7.30 symptom days). Other strategies cost 8 dollars to 76 dollars more and increased duration of symptoms by up to 1.3 days. In probabilistic sensitivity analysis, this strategy was always the most effective strategy and was also least expensive 58% of the time. For patients with vaginitis symptoms undiagnosed by pelvic examination, wet mount preparations and related office tests, a comprehensive, pH-guided testing strategy at the initial office visit is less expensive and more effective than ordering tests sequentially.

  8. Optical diagnostics in the advanced test accelerator (ATA) environment

    International Nuclear Information System (INIS)

    Chong, Y.P.; Cornish, J.P.; Donnelly, D.

    1987-05-01

    The ATA is a 50-MeV, 10-kA, 70-ns pulsed electron beam accelerator that generates an extremely harsh environment for diagnostic measurements. Diagnostic targets placed in the beamline are subject to damage, frequently being destroyed by a single pulse. High radiation (x-ray, gamma, and neutron) and electromagnetic interference levels preclude placing components near the beamline that are susceptible to radiation damage. Examples of such components are integrated circuit elements, hydrocarbons such as Teflon insulation, and optical components that darken, resulting in transmission loss. Optical diagnostics play an important part in measuring experimental parameters such as the beam current density profile. A large number of optical lines of sight (LOS) are routinely deployed along the experimental beamlines that use the ATA beam. Gated TV cameras are located outside the accelerator tunnel, because the tunnel is inaccessible during operations. We will describe and discuss the difficulties, problems, and solutions encountered in making optical measurements in the ATA environment

  9. Detecting Malaria Hotspots: A Comparison of Rapid Diagnostic Test, Microscopy, and Polymerase Chain Reaction.

    Science.gov (United States)

    Mogeni, Polycarp; Williams, Thomas N; Omedo, Irene; Kimani, Domtila; Ngoi, Joyce M; Mwacharo, Jedida; Morter, Richard; Nyundo, Christopher; Wambua, Juliana; Nyangweso, George; Kapulu, Melissa; Fegan, Gregory; Bejon, Philip

    2017-11-27

    Malaria control strategies need to respond to geographical hotspots of transmission. Detection of hotspots depends on the sensitivity of the diagnostic tool used. We conducted cross-sectional surveys in 3 sites within Kilifi County, Kenya, that had variable transmission intensities. Rapid diagnostic test (RDT), microscopy, and polymerase chain reaction (PCR) were used to detect asymptomatic parasitemia, and hotspots were detected using the spatial scan statistic. Eight thousand five hundred eighty-one study participants were surveyed in 3 sites. There were statistically significant malaria hotspots by RDT, microscopy, and PCR for all sites except by microscopy in 1 low transmission site. Pooled data analysis of hotspots by PCR overlapped with hotspots by microscopy at a moderate setting but not at 2 lower transmission settings. However, variations in degree of overlap were noted when data were analyzed by year. Hotspots by RDT were predictive of PCR/microscopy at the moderate setting, but not at the 2 low transmission settings. We observed long-term stability of hotspots by PCR and microscopy but not RDT. Malaria control programs may consider PCR testing to guide asymptomatic malaria hotspot detection once the prevalence of infection falls. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  10. Laboratory Diagnosis of Malaria: Comparison of Manual and Automated Diagnostic Tests

    Directory of Open Access Journals (Sweden)

    Samina Naz Mukry

    2017-01-01

    Full Text Available Malaria is the second most prevalent disease in Pakistan resulting in ~30,000 annual deaths. In endemic countries like Pakistan precise and timely diagnosis of malaria is imperative to overcome the associated risks of fatal outcomes. Malarial parasite was screened in 128 malaria suspected patients and 150 healthy controls, by species-specific PCR, microscopy of blood smears, hemoanalyzer Sysmex XE-2100, and rapid test devices (First Response Malaria® and ICT Malaria Combo®. The microscopy detected MP in 126 samples (parasite load/µl 386–53712/µl; 71.094% were infected with Plasmodium vivax and 14.844% with P. falciparum while 14.062% had mixed P. vivax and P. falciparum infection. The mean parasite load for P. vivax and P. falciparum was 14496/µl and 24410/µl, respectively. The abnormal scattergrams of DIFF, WBC/ Baso, IMI channel, and RET-EXT on Sysmex XE-2100 supported 99.2% parasite detection, whereas only 93% of confirmed malaria cases were detected by both rapid tests. About 127 samples were positive by PCR. Since Sysmex XE-2100 automatically detected the presence of malarial parasite with high sensitivity, it can be a good option for presumptive diagnosis in endemic areas. Microscopy remains the gold standard to confirm MP in suspected patients. Rapid diagnostic tests have acceptable sensitivity and specificity.

  11. Diagnostic testing for Clostridium difficile in Italian microbiological laboratories.

    Science.gov (United States)

    Spigaglia, Patrizia; Barbanti, Fabrizio; Morandi, Matteo; Moro, Maria Luisa; Mastrantonio, Paola

    2016-02-01

    A laboratory diagnosis survey of Clostridium difficile infection (CDI) was performed in Italy in 2012-2013. Questionnaires from 278 healthcare settings from 15 regions of Italy were collected and analysed. Eighty seven percent of the laboratories declared to routinely perform CDI diagnosis, 99% of them only after the clinician's request. Among the 216 laboratories providing information on the size of the hospitals in which they were located, 65 had more than 500 beds (large hospitals), while 151 had less than 500 beds (small hospitals). The average percentage of positive tests for C. difficile toxins was 12.2%. Almost half of the laboratories (42%) used immunoenzymatic assay (EIA) for Tox A/B as a stand-alone method, while only 34% used an algorithm for CDI as indicated by the European guidelines. A low percentage of laboratories performed molecular assays or C. difficile culture, 25% and 29%, respectively. Most laboratories (161/278) declared to type C. difficile strains, the majority in collaboration with a reference laboratory. Among the 103 C. difficile clinical isolates collected during the study, 31 different PCR-ribotypes were identified. PCR-ribotype 356/607 (27%) was predominant, followed by 018 (12%). These two PCR-ribotypes show 87.5% of similarity in ribotyping profile. PCR-ribotypes 027 and 078 represented 8% and 4% of the strains, respectively. Four PCR-ribotypes (027, 033, 078 and 126) were positive for the binary toxin CDT. In particular, PCR-ribotype 033 produces only CDT, and it has recently been associated with symptomatic cases. The majority of strains were multidrug resistant. In particular, all strains PCR-ribotypes 356/607 and 018 were resistant to moxifloxacin, rifampicin, erythromycin and clindamycin. The results obtained highlight the need to raise awareness to the microbiological diagnosis of CDI among clinicians and to implement and harmonize diagnostic methods for CDI in Italian laboratories in the perspective of a future national

  12. A diagnostic model incorporating P50 sensory gating and neuropsychological tests for schizophrenia.

    Directory of Open Access Journals (Sweden)

    Jia-Chi Shan

    Full Text Available OBJECTIVES: Endophenotypes in schizophrenia research is a contemporary approach to studying this heterogeneous mental illness, and several candidate neurophysiological markers (e.g. P50 sensory gating and neuropsychological tests (e.g. Continuous Performance Test (CPT and Wisconsin Card Sorting Test (WCST have been proposed. However, the clinical utility of a single marker appears to be limited. In the present study, we aimed to construct a diagnostic model incorporating P50 sensory gating with other neuropsychological tests in order to improve the clinical utility. METHODS: We recruited clinically stable outpatients meeting DSM-IV criteria of schizophrenia and age- and gender-matched healthy controls. Participants underwent P50 sensory gating experimental sessions and batteries of neuropsychological tests, including CPT, WCST and Wechsler Adult Intelligence Scale Third Edition (WAIS-III. RESULTS: A total of 106 schizophrenia patients and 74 healthy controls were enrolled. Compared with healthy controls, the patient group had significantly a larger S2 amplitude, and thus poorer P50 gating ratio (gating ratio = S2/S1. In addition, schizophrenia patients had a poorer performance on neuropsychological tests. We then developed a diagnostic model by using multivariable logistic regression analysis to differentiate patients from healthy controls. The final model included the following covariates: abnormal P50 gating (defined as P50 gating ratio >0.4, three subscales derived from the WAIS-III (Arithmetic, Block Design, and Performance IQ, sensitivity index from CPT and smoking status. This model had an adequate accuracy (concordant percentage = 90.4%; c-statistic = 0.904; Hosmer-Lemeshow Goodness-of-Fit Test, p = 0.64>0.05. CONCLUSION: To the best of our knowledge, this is the largest study to date using P50 sensory gating in subjects of Chinese ethnicity and the first to use P50 sensory gating along with other neuropsychological tests

  13. [Diagnostic of congenital syphilis: a comparison between serological tests in mothers and their newborns].

    Science.gov (United States)

    Barsanti, C; Valdetaro, F; de Albuquerque Diniz, E M; Succi, R C

    1999-01-01

    For the purpose of establishing the incidence of maternal and congenital syphilis among pregnant women at delivery and their respective newborns, a study was carried out to determine treponemic and non-treponemic serology in one thousand (1,000) parturient women and their children at Santa Marcelina Hospital - São Paulo, between June 95 and July 96. All blood samples (maternal venous, umbilical cord and newborn venous) were VDRL-tested, treponemic tests (TPHA, ELISA IgG, ELISA IgM) being applied whenever one of the samples from mother or newborn proved positive. Further, an anti-HIV search was run through ELISA among VDRL-positive mothers. Among the 1,000 parturients, 24 (2.4%) were found to be VDRL-reactive; 18 (1.8%) newborn children of these 24 mothers presented positive serology in their umbilical cord blood and 19 (1.9%) in venous blood. No positive newborns were found for negative mothers. From the high occurrence of maternal and congenital syphilis in this group of patients, we propose a VDRL maternal test as a way of selecting gestational and congenital syphilis cases, since this test appeared to be sufficiently capable of such diagnoses. Of the treponemic tests, the ELISA test did not enhance diagnostic sensitivity.

  14. Irradiation test of diagnostic components for ITER application in a fission reactor, Japan Materials Testing Reactor

    International Nuclear Information System (INIS)

    Shikama, T.; Nishitani, T.; Kakuta, T.

    2003-01-01

    Radiation effects on components and materials will be one of the most serious technological issues in fusion systems realizing burning plasmas. Especially, diagnostic components, which should play crucial roles to control plasmas and to understand physics of burning plasmas, will be exposed to high-flux neutrons and gamma-rays. Dynamics radiation effects will affects performance of components substantially from beginning of exposure to radiation environments, and accumulated radiation effects will gradually degrade their functioning abilities in the course of their services. High-power-density fission reactors will be only realistic tools to simulate the irradiation environments expected in burning-plasma fusion machines such as the ITER, at present. Some key diagnostic components, namely magnetic coils, bolometers, and optical fibers, were irradiation-tested in a fission reactor, JMTR, to evaluate their performances under heavy irradiation environments. Results indicate that the ITER-relevant diagnostic components could be developed in time, though there are still some technological problems to overcome. (author)

  15. Publications on diagnostic test evaluation in family medicine journals: an optimal search strategy.

    NARCIS (Netherlands)

    Devillé, W L; Bezemer, P D; Bouter, L M

    Search strategies for articles reporting on diagnostic test evaluations have been subjected to less research than those in the domain of clinical trials. We set out to develop an optimal search strategy for publications on diagnostic test evaluations in general, that could be added to keywords

  16. Characteristics of diagnostic tests used in the 2002 low-pathogenicity avian influenza H7N2 outbreak in Virginia.

    Science.gov (United States)

    Elvinger, François; Akey, Bruce L; Senne, Dennis A; Pierson, F William; Porter-Spalding, Barbara A; Spackman, Erica; Suarez, David L

    2007-07-01

    An outbreak of low-pathogenicity avian influenza (LPAI) H7N2 occurred in 2002 in the Shenandoah Valley, a high-density poultry production region in Virginia. Infected flocks were identified through a combination of observation of clinical signs and laboratory diagnostic tests designed to detect avian influenza (AI) antibodies, virus, or H7-specific RNA. In this report, fitness for purpose of 3 virus/RNA detection assays used during the outbreak was examined: 1) antigen capture enzyme immunoassay (AC-EIA), 2) real-time reverse transcription polymerase chain reaction (RRT-PCR), and 3) virus isolation (VI). Results from testing 762 turkey and 2,216 chicken tracheal swab pooled specimens were analyzed to determine diagnostic sensitivities and specificities of these tests under field conditions using Bayesian techniques for validation of diagnostic tests in the absence of a "gold standard." Diagnostic sensitivities (with 95% probability intervals) in turkeys of AC-EIA and RRT-PCR, in reference to VI, were 65.9 (50.6; 81.3)% and 85.1 (71.9; 95.7)% and of VI 92.9 (78.0; 98.8)% in reference to AC-EIA or 88.7 (76.0; 97.2)% in reference to RRT-PCR; in chickens, diagnostic sensitivities were 75.1 (45.6; 94.2)%, 86.3 (65.9; 97.1)%, and 86.2 (65.8; 97.1)% or 86.3 (66.4; 97.2)%, respectively. Specificities were 99.1 (97.9; 99.8)%, 98.9 (98.0; 99.5)%, and 98.6 (97.4; 99.4)% or 98.8 (97.8; 99.5)% in turkeys and between 99.25% and 99.27% with probability intervals of approximately +/-0.4% for all tests in chickens. Simultaneous use of AC-EIA and RRT-PCR contributed significantly to the rapid control of the outbreak, but the AI RRT-PCR assay with >85% sensitivity and approximately 99% specificity, combined with relatively low cost and fast turnaround, could be used as the sole diagnostic test in outbreaks of LPAI.

  17. Test and Product Review: Pediatric Attention Disorders Diagnostic Screener

    Science.gov (United States)

    Huang, Leesa V.

    2009-01-01

    This article presents a comprehensive evaluation of the Pediatric Attention Disorders Diagnostic Screener (PADDS). PADDS was developed as a computer-based assessment system to screen for attention and executive function disorders in children aged 6 through 12 years. The evaluation of the PADDS indicated that it can be a useful and efficient…

  18. Diagnostic accuracy of triage tests to exclude pulmonary embolism

    NARCIS (Netherlands)

    Mac Gillavry, M. R.; Lijmer, J. G.; Sanson, B. J.; Büller, H. R.; Brandjes, D. P.

    2001-01-01

    We performed a study in 403 prospectively included patients with suspected pulmonary embolism to compare the accuracy of a combination of the SimpliRED D-dimer assay and an intuitive clinical probability estimate with either one alone. Based on a conjoint diagnostic refer, ence standard, including

  19. Comparison of Rapid Diagnostic Tests and Microscopy for Malaria ...

    African Journals Online (AJOL)

    Presumptive treatment of malaria results in significant overuse of antimalarials. This study compared the diagnostic accuracy of Histidine Rich Protein II and plasmodium lactate dehydrogenase (pLDH)-based Rapid Kits( RDTs)and using expert microscopy as the gold standard for the detection of falciparum and ...

  20. Comparison of Rapid Diagnostic Tests and Microscopy for Malaria

    African Journals Online (AJOL)

    boaz

    Presumptive treatment of malaria results in significant overuse of antimalarials. This study compared the diagnostic accuracy of. Histidine Rich Protein II and plasmodium lactate dehydrogenase (pLDH)-based Rapid Kits( RDTs)and using expert microscopy as the gold standard for the detection of falciparum and ...

  1. Comparison of diagnostic tests for the detection of Brucella spp. in camel sera

    Directory of Open Access Journals (Sweden)

    Gwida Mayada M

    2011-12-01

    Full Text Available Abstract Background Brucellosis in livestock causes enormous losses for economies of developing countries and poses a severe health risk to consumers of dairy products. Little information is known especially on camel brucellosis and its impact on human health. For surveillance and control of the disease, sensitive and reliable detection methods are needed. Although serological tests are the mainstay of diagnosis in camel brucellosis, these tests have been directly transposed from cattle without adequate validation. To date, little information on application of real-time PCR for detection of Brucella in camel serum is available. Therefore, this study was performed to compare the diagnostic efficiency of different serological tests and real-time PCR in order to identify the most sensitive, rapid and simple combination of tests for detecting Brucella infection in camels. Findings A total of 895 serum samples collected from apparently healthy Sudanese camels was investigated. Sudan is a well documented endemic region for brucellosis with cases in humans, ruminants, and camels. Rose Bengal Test (RBT, Complement Fixation Test (CFT, Slow Agglutination Test (SAT, Competitive Enzyme Linked Immunosorbant Assay (cELISA and Fluorescence Polarization Assay (FPA as well as real-time PCR were used. Our findings revealed that bcsp31 kDa real-time PCR detected Brucella DNA in 84.8% (759/895 of the examined samples, of which 15.5% (118/759 were serologically negative. Our results show no relevant difference in sensitivity between the different serological tests. FPA detected the highest number of positive cases (79.3% followed by CFT (71.4%, RBT (70.7%, SAT (70.6% and cELISA (68.8%. A combination of real-time PCR with one of the used serological tests identified brucellosis in more than 99% of the infected animals. 59.7% of the examined samples were positive in all serological tests and real-time PCR. A subpopulation of 6.8% of animals was positive in all

  2. New biomarkers defining a novel early stage of Fabry nephropathy: A diagnostic test study.

    Science.gov (United States)

    Aguiar, Patrício; Azevedo, Olga; Pinto, Rui; Marino, Jacira; Baker, Robert; Cardoso, Carlos; Ducla Soares, José Luís; Hughes, Derralynn

    2017-06-01

    Renal involvement in Fabry disease is a major determinant of overall disease prognosis and early enzyme replacement therapy seems effective in preventing progression of kidney injury. Gb3 storage, glomerular sclerosis and tubulo-interstitial fibrosis may occur with minimal or no changes on standard renal tests, hence alternative markers of renal dysfunction are crucial. In this study we compared several biomarkers with albuminuria in the identification of incipient Fabry nephropathy and their diagnostic accuracy to identify chronic kidney disease (CKD) stage≥2. In this multicentre, prospective, cross-sectional and diagnostic test study, a cohort of 78 Fabry patients and 25 healthy controls was consecutively recruited. Patients were grouped by severity of nephropathy: 1) albuminuria300mg/g; 4) glomerular filtration rate (GFR)Fabry patients, even in the subgroup of patients without evidence of nephropathy. We also found inverse significant correlations between estimated GFR and collagen type IV (ρ=-0.289; p=0.003) or N-acetyl-β-glucosaminidase (ρ=-0.448; p<0.001), which were stronger than with albumin (ρ=-0.274; p=0.019). There was also better diagnostic accuracy of N-acetyl-β-glucosaminidase to predict CKD stage≥2. These results suggest that studied biomarkers may overcome the limitations of albuminuria as sensitive marker of early renal dysfunction and as marker for CKD progression risk. These biomarkers may also define novel early stages of nephropathy characterized by mesangial expansion and/or tubular damage. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. The computerized adaptive diagnostic test for major depressive disorder (CAD-MDD): a screening tool for depression.

    Science.gov (United States)

    Gibbons, Robert D; Hooker, Giles; Finkelman, Matthew D; Weiss, David J; Pilkonis, Paul A; Frank, Ellen; Moore, Tara; Kupfer, David J

    2013-07-01

    To develop a computerized adaptive diagnostic screening tool for depression that decreases patient and clinician burden and increases sensitivity and specificity for clinician-based DSM-IV diagnosis of major depressive disorder (MDD). 656 individuals with and without minor and major depression were recruited from a psychiatric clinic and a community mental health center and through public announcements (controls without depression). The focus of the study was the development of the Computerized Adaptive Diagnostic Test for Major Depressive Disorder (CAD-MDD) diagnostic screening tool based on a decision-theoretical approach (random forests and decision trees). The item bank consisted of 88 depression scale items drawn from 73 depression measures. Sensitivity and specificity for predicting clinician-based Structured Clinical Interview for DSM-IV Axis I Disorders diagnoses of MDD were the primary outcomes. Diagnostic screening accuracy was then compared to that of the Patient Health Questionnaire-9 (PHQ-9). An average of 4 items per participant was required (maximum of 6 items). Overall sensitivity and specificity were 0.95 and 0.87, respectively. For the PHQ-9, sensitivity was 0.70 and specificity was 0.91. High sensitivity and reasonable specificity for a clinician-based DSM-IV diagnosis of depression can be obtained using an average of 4 adaptively administered self-report items in less than 1 minute. Relative to the currently used PHQ-9, the CAD-MDD dramatically increased sensitivity while maintaining similar specificity. As such, the CAD-MDD will identify more true positives (lower false-negative rate) than the PHQ-9 using half the number of items. Inexpensive (relative to clinical assessment), efficient, and accurate screening of depression in the settings of primary care, psychiatric epidemiology, molecular genetics, and global health are all direct applications of the current system. © Copyright 2013 Physicians Postgraduate Press, Inc.

  4. Clinical value of radiocontrast media skin tests as a prescreening and diagnostic tool in hypersensitivity reactions.

    Science.gov (United States)

    Kim, Sae-Hoon; Jo, Eun-Jung; Kim, Mi-Yeong; Lee, Seung-Eun; Kim, Min-Hye; Yang, Min-Suk; Song, Woo-Jung; Choi, Sang-Il; Kim, Jae-Hyoung; Chang, Yoon-Seok

    2013-04-01

    Some radiocontrast media (RCM) hypersensitivity reactions may have underlying IgE- or T-cell-mediated mechanisms. RCM skin testing may be useful for predicting future reactions. To investigate the clinical value of RCM skin testing before computed tomography and after RCM hypersensitivity reactions. Patients who underwent RCM skin testing were a prospective sample of convenience at a single medical center and were tested just before their pending nonionic RCM-enhanced computed tomogram. In addition, skin test data of patients who were referred to the allergy clinic because of their previous RCM hypersensitivity reactions were reviewed retrospectively. A total of 1048 patients enrolled in the study prospectively. Of these, 672 (64.1%) had never been exposed to RCM. Of the 376 previously exposed to RCM, 61 (16.2%) had a history of at least one mild RCM-associated reaction, 56 (91.8%) had immediate reactions, and 5 had no-immediate reactions. There was only 1 positive immediate hypersensitivity RCM skin test result (0.09%). There were 51 mild immediate reactions (4.9%), 1 moderate immediate reaction (0.09%), 8 mild nonimmediate reactions (0.76%), and 1 moderate nonimmediate reaction (0.09%). There was only 1 positive delayed hypersensitivity skin test result (0.09%), retrospectively determined, in 1 (11.1%) of the nonimmediate RCM-associated reactions. Sensitivity of RCM skin testing was significantly higher with severe immediate reactions (57.1%) than mild reactions (12.9%) and moderate reactions (25.0%) in the retrospective review of diagnostic skin test data (P = .03). RCM skin testing for screening is of no clinical utility in predicting hypersensitivity reactions. RCM skin testing may have modest utility in retrospectively evaluating severe adverse reactions. Copyright © 2013 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  5. Sensitivity of the diagnostic radiological index of protection to procedural factors in fluoroscopy.

    Science.gov (United States)

    Jones, A Kyle; Pasciak, Alexander S; Wagner, Louis K

    2016-07-01

    To evaluate the sensitivity of the diagnostic radiological index of protection (DRIP), used to quantify the protective value of radioprotective garments, to procedural factors in fluoroscopy in an effort to determine an appropriate set of scatter-mimicking primary beams to be used in measuring the DRIP. Monte Carlo simulations were performed to determine the shape of the scattered x-ray spectra incident on the operator in different clinical fluoroscopy scenarios, including interventional radiology and interventional cardiology (IC). Two clinical simulations studied the sensitivity of the scattered spectrum to gantry angle and patient size, while technical factors were varied according to measured automatic dose rate control (ADRC) data. Factorial simulations studied the sensitivity of the scattered spectrum to gantry angle, field of view, patient size, and beam quality for constant technical factors. Average energy (Eavg) was the figure of merit used to condense fluence in each energy bin to a single numerical index. Beam quality had the strongest influence on the scattered spectrum in fluoroscopy. Many procedural factors affect the scattered spectrum indirectly through their effect on primary beam quality through ADRC, e.g., gantry angle and patient size. Lateral C-arm rotation, common in IC, increased the energy of the scattered spectrum, regardless of the direction of rotation. The effect of patient size on scattered radiation depended on ADRC characteristics, patient size, and procedure type. The scattered spectrum striking the operator in fluoroscopy is most strongly influenced by primary beam quality, particularly kV. Use cases for protective garments should be classified by typical procedural primary beam qualities, which are governed by the ADRC according to the impacts of patient size, anatomical location, and gantry angle.

  6. Recommendations for reporting results of diagnostic genetic testing (biochemical, cytogenetic and molecular genetic)

    NARCIS (Netherlands)

    Claustres, Mireille; Kozich, Viktor; Dequeker, Els; Fowler, Brain; Hehir-Kwa, Jayne Y.; Miller, Konstantin; Oosterwijk, Cor; Peterlin, Borut; van Ravenswaaij-Arts, Conny; Zimmermann, Uwe; Zuffardi, Orsetta; Hastings, Ros J.; Barton, David E.

    Genetic test results can have considerable importance for patients, their parents and more remote family members. Clinical therapy and surveillance, reproductive decisions and genetic diagnostics in family members, including prenatal diagnosis, are based on these results. The genetic test report

  7. [New diagnostic tests for tuberculosis in southern countries: from theory to practice in southern countries].

    Science.gov (United States)

    Bonnet, M

    2011-12-01

    Tuberculosis (TB) is responsible of 1.7 millions of deaths per year worldwide. In high burden countries sputum smear-microscopy diagnoses only half of the cases of pulmonary TB. It is unlikely that a new test will replace smear-microscopy in peripheral services in the short term. Between 2007 and 2009 WHO recommended the introduction of seven new tests or diagnostic approaches for high burden countries, for peripheral laboratories : 1) the optimisation of smear-microscopy using the revised smear-positive case definitions; 2) examination of two specimens instead of three; 3) examination of two specimens collected on the same day; 4) the use of light-emitting diode based fluorescence microscopy and for reference laboratories: 5) the use of liquid medium culture; 6) the use of rapid antigenic identification tests; 7) the rapid detection of rifampicin resistance. The recent development of a fully automated nucleic acid amplification test for both TB detection and detection of rifampicin resistance will soon improve the diagnosis of TB in HIV infected patients outside reference laboratories in high burden countries. Despite the recent advances in TB diagnosis, there is need for more research to develop point of care tests that do not depend on sputum specimens, that are practicable at peripheral units and that are highly sensitive in HIV infected patients and children. Copyright © 2011 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  8. The diagnostic accuracy and outcomes after coronary computed tomography angiography vs. conventional functional testing in patients with stable angina pectoris

    DEFF Research Database (Denmark)

    Nielsen, Lene H; Ortner, Nino; Nørgaard, Bjarne L

    2014-01-01

    suspected of stable coronary artery disease (CAD). METHODS AND RESULTS: We systematically searched for studies published from January 2002 to February 2013 examining the diagnostic accuracy (defined as at least ≥50% luminal obstruction on invasive coronary angiography) and outcomes of coronary CTA (≥16......AIMS: To systematically review and perform a meta-analysis of the diagnostic accuracy and post-test outcomes of conventional exercise electrocardiography (XECG) and single-photon emission computed tomography (SPECT) compared with coronary computed tomography angiography (coronary CTA) in patients...... slice) in comparison with XECG and SPECT. The search revealed 11 eligible studies (N = 1575) comparing the diagnostic accuracy and 7 studies (N = 216.603) the outcomes of coronary CTA vs. XECG or/and SPECT. The per-patient sensitivity [95% confidence interval (95% CI)] to identify significant CAD was 98...

  9. Does more favourable handling of the cerebrospinal fluid increase the diagnostic sensitivity of Borrelia burgdorferi sensu lato-specific PCR in Lyme neuroborreliosis?

    Science.gov (United States)

    Forselv, Kristine J N; Lorentzen, Åslaug R; Ljøstad, Unn; Mygland, Åse; Eikeland, Randi; Kjelland, Vivian; Noraas, Sølvi; Quarsten, Hanne

    2018-04-01

    Tests for direct detection of Borrelia burgdorferi sensu lato (Bb) in Lyme neuroborreliosis (LNB) are needed. Detection of Bb DNA using PCR is promising, but clinical utility is hampered by low diagnostic sensitivity. We aimed to examine whether diagnostic sensitivity can be improved by the use of larger cerebrospinal fluid (CSF) volumes and faster handling of samples. Patients who underwent CSF examination for LNB were included. We collected two millilitres of CSF for PCR analysis, extracted DNA from the pellets within 24 h and analysed the eluate by two real-time PCR protocols (16S rRNA and OspA). Patients who fulfilled diagnostic criteria for LNB were classified as LNB cases and the rest as controls. Bb DNA in CSF was detected by PCR in seven of 28 adults with LNB. Two were Bb antibody negative. No Bb DNA was detected in CSF from 137 controls. Diagnostic sensitivity was 25% and specificity 100%. There was a non-significant trend towards larger CSF sample volume, faster handling of the sample, shorter duration of symptoms, and higher CSF cell count in the PCR-positive cases. We did not find that optimized handling of CSF increased diagnostic sensitivity of PCR in adults with LNB. However, our case series is small and we hypothesize that the importance of these factors will be clarified in further studies with larger case series and altered study design. PCR for diagnosis of LNB may be useful in cases without Bb antibodies due to short duration of symptoms.

  10. Confirming nasogastric tube placement: Is the colorimeter as sensitive and specific as X-ray? A diagnostic accuracy study.

    Science.gov (United States)

    Mordiffi, Siti Zubaidah; Goh, Mien Li; Phua, Jason; Chan, Yiong-Huak

    2016-09-01

    The effect of delivering enteral nutrition or medications via a nasogastric tube that is inadvertently located in the tracheobronchial tract can cause respiratory complications. Although radiographic examination is accepted as the gold standard for confirming the position of patients' enteral tubes, it is costly, involves risks of radiation, and is not failsafe. Studies using carbon dioxide sensors to detect inadvertent nasogastric tube placements have been conducted in intensive care settings. However, none involved patients in general wards. The objective of this study was to ascertain the diagnostic measure of colorimeter, with radiographic examination as the reference standard, to confirm the location of nasogastric tubes in patients. A prospective observational study of a diagnostic test. This study was conducted in the general wards of an approximately 1100-bed acute care tertiary hospital of an Academic Medical Center in Singapore. Adult patients with nasogastric tubes admitted to the general wards were recruited into the study. The colorimeter was attached to the nasogastric tube to detect for the presence of carbon dioxide, suggestive of a tracheobronchial placement. The exact location of the nasogastric tube was subsequently confirmed by a radiographic examination. A total of 192 tests were undertaken. The colorimeter detected carbon dioxide in 29 tested nasogastric tubes, of which radiographic examination confirmed that four tubes were located in the tracheobronchial tract. The colorimeter failed to detect carbon dioxide in one nasogastric tube that was located in the tracheobronchial tract, thus, demonstrating a sensitivity of 0.80 [95% CI (0.376, 0.964)]. The colorimeter detected absence of carbon dioxide in 163 tested nasogastric tubes in which radiographic examination confirmed 160 gastrointestinal and one tracheobronchial placements, demonstrating a specificity of 0.865 [95% CI (0.808, 0.907)]. The colorimeter detected one tracheobronchial

  11. Clinical approach to obscure GI bleeding - Diagnostic testing and management

    Directory of Open Access Journals (Sweden)

    Prashanth Prabakaran

    2013-01-01

    Full Text Available Obscure gastrointestinal bleeding (OGIB can present as a diagnostic dilemma and management can be challenging. The search for causes of OGIB is usually centered on visualizing the small bowel, and in the past decade, the technology to visualize the entire small bowel has significantly advanced. Moreover, small bowel endoscopic imaging has replaced, in many instances, prior radiographic evaluation for obscure GI bleeding. These new modalities, such as small bowel capsule endoscopy (CE, balloon-assisted deep enteroscopy [double balloon enteroscopy (DBE and single balloon enteroscopy (SBE], and overtube-assisted deep enteroscopy (spiral enteroscopy, are paving the way toward more accurately identifying and treating patients with OGIB. We will review the diagnostic modalities available in evaluating a patient with OGIB and also propose the management based on clinical and endoscopic findings.

  12. LeRC rail accelerators: test designs and diagnostic techniques

    International Nuclear Information System (INIS)

    Zana, L.M.; Kerslake, W.R.; Sturman, J.C.; Wang, S.Y.; Terdan, F.F.

    1984-01-01

    The feasibility of using rail accelerators for various in-space and to-space propulsion applications was investigated. A 1 meter, 24 sq mm bore accelerator was designed with the goal of demonstrating projectile velocities of 15 km/sec using a peak current of 200 kA. A second rail accelerator, 1 meter long with a 156.25 sq mm bore, was designed with clear polycarbonate sidewalls to permit visual observation of the plasma arc. A study of available diagnostic techniques and their application to the rail accelerator is presented. Specific topics of discussion include the use of interferometry and spectroscopy to examine the plasma armature as well as the use of optical sensors to measure rail displacement during acceleration. Standard diagnostics such as current and voltage measurements are also discussed. 15 references

  13. Is the urine spot protein/creatinine ratio a valid diagnostic test for pre-eclampsia?

    Science.gov (United States)

    Sethuram, R; Kiran, T S Usha; Weerakkody, A N A

    2011-01-01

    The objective of this study was to assess the value of the spot protein/creatinine ratio as the diagnostic test for pre-eclampsia by correlating it to the 24 h urine protein. For the spot test, this study uses the cut-off value recognised by the International Society for the Study of Hypertension in Pregnancy (ISSHP). Ours was a correlational study made in the setting of the antenatal assessment unit/antenatal ward in a District General Hospital. Patients at >24 weeks' gestation with hypertension and >1+ proteinuria (n = 32) were included in the study. A 10 ml sample of urine was collected for the spot protein/creatinine ratio (PCR) before the 24 h collection was started. Spot PCR samples were stored at -18°C until the end of the study period. The results of the spot PCR were correlated to 24 h results using Pearson's correlation coefficient. Main outcome measures were correlation coefficient, sensitivity, specificity, positive and negative predictive values. Correlation was significant (r(2) = 0.82). Sensitivity, 83%; specificity, 92%; positive likelihood ratio, 10.3; negative likelihood ratio, 0.18. The spot PCR correlates well to the 24 h urine protein. The new cut-off values recognised by the ISSHP are producing consistent results. The evidence in favour of the spot PCR needs to be reassessed by larger studies.

  14. Specificity and sensitivity assessment of selected nasal provocation testing techniques

    Directory of Open Access Journals (Sweden)

    Edyta Krzych-Fałta

    2016-12-01

    Full Text Available Introduction: Nasal provocation testing involves an allergen-specific local reaction of the nasal mucosa to the administered allergen. Aim: To determine the most objective nasal occlusion assessment technique that could be used in nasal provocation testing. Material and methods : A total of 60 subjects, including 30 patients diagnosed with allergy to common environmental allergens and 30 healthy subjects were enrolled into the study. The method used in the study was a nasal provocation test with an allergen, with a standard dose of a control solution and an allergen (5,000 SBU/ml administered using a calibrated atomizer into both nostrils at room temperature. Early-phase nasal mucosa response in the early phase of the allergic reaction was assessed via acoustic rhinometry, optical rhinometry, nitric oxide in nasal air, and tryptase levels in the nasal lavage fluid. Results : In estimating the homogeneity of the average values, the Levene’s test was used and receiver operating characteristic curves were plotted for all the methods used for assessing the nasal provocation test with an allergen. Statistically significant results were defined for p < 0.05. Of all the objective assessment techniques, the most sensitive and characteristic ones were the optical rhinometry techniques (specificity = 1, sensitivity = 1, AUC = 1, PPV = 1, NPV = 1. Conclusions : The techniques used showed significant differences between the group of patients with allergic rhinitis and the control group. Of all the objective assessment techniques, those most sensitive and characteristic were the optical rhinometry.

  15. Non-animal sensitization testing: state-of-the-art.

    Science.gov (United States)

    Vandebriel, Rob J; van Loveren, Henk

    2010-05-01

    Predictive tests to identify the sensitizing properties of chemicals are carried out using animals. In the European Union timelines for phasing out many standard animal tests were established for cosmetics. Following this policy, the new European Chemicals Legislation (REACH) favors alternative methods, if validated and appropriate. In this review the authors aim to provide a state-of-the art overview of alternative methods (in silico, in chemico, and in vitro) to identify contact and respiratory sensitizing capacity and in some occasions give a measure of potency. The past few years have seen major advances in QSAR (quantitative structure-activity relationship) models where especially mechanism-based models have great potential, peptide reactivity assays where multiple parameters can be measured simultaneously, providing a more complete reactivity profile, and cell-based assays. Several cell-based assays are in development, not only using different cell types, but also several specifically developed assays such as three-dimenionally (3D)-reconstituted skin models, an antioxidant response reporter assay, determination of signaling pathways, and gene profiling. Some of these assays show relatively high sensitivity and specificity for a large number of sensitizers and should enter validation (or are indeed entering this process). Integrating multiple assays in a decision tree or integrated testing system is a next step, but has yet to be developed. Adequate risk assessment, however, is likely to require significantly more time and efforts.

  16. Diagnostic value of lasik test for detection of lumbar discopathy in patients attending emergency department with acute low back pain

    Science.gov (United States)

    Aala, Alireza; Alizadeh Shahri, Saeid; Meshkini, Ali; Shams Vahdati, Samad

    2012-01-01

    Abstract: Background: Low back pain is one of the most important health problems. Disk herniation is one of the common causes of low back pain. Accurate examination is the best and simplest diagnostic methods. Physical examination, Straight leg raise (SLR) and neurologic tests as well as other tests are usually used to locate the exact place of herniation. Paraclinical studies such as magnetic resonance imaging (MRI) should be used because of the low diagnostic efficiency of physical examination. Methods: 100 patients attended the emergency unit because of back pain or radicular pain, were enrolled in the study. SLR, Reverse- SLR (R-SLR) and Crossed-SLR (C-SLR) tests were performed for all patients. Then, the patients were referred to the neurosurgery unit for treatment. Lumbar MRI was taken for all patients. Then, all patients were followed up and these data were collected. Results: Sensitivity and specificity of SLR test, C-SLR, and R-SLR tests was 77.52% and 36.36%, 29.21% and 90.9%, and 88.89% and 10.94%, respectively. There was no significant relationship between MRI and positive discopathy in the physical examination and SLR (P=0.11). Conclusions: SLR test has high sensitivity and low specificity. If the SLR test was accompanied by with physical examination the resulting sensitivity and specificity will increase. Findings of this study showed that SLR test has more sensitivity, while C-SLR has more specificity in low back pain diagnosis. Keywords: SLR test, Low Back Pain, Discopathy, Straight leg raise

  17. Patch test sensitivity to the preservative Kathon CG in Spain.

    Science.gov (United States)

    Hasson, A; Guimaraens, D; Condé-Salazar, L

    1990-05-01

    Kathon CG is a very well studied preservative used in cosmetics and toiletries. It is effective in low concentrations (3 to 15 ppm active ingredients) and exhibits outstanding antimicrobial activity against gram-negative and gram-positive bacteria, yeasts and fungi. Although this biocide is not considered to pose a toxicological hazard at recommended use levels, the sensitizing potential of Kathon CG has been established. From November 1988 to June 1989, we patch tested 626 unselected contact dermatitis patients with Kathon CG solution containing 200 ppm active ingredients and obtained 22 (3.5%) positive reactions. Relevance was established in 7 of the 22 patients. Women were predominantly sensitized, the principal source of sensitization being cosmetics.

  18. Self-diagnosis of malaria by travelers and expatriates: assessment of malaria rapid diagnostic tests available on the internet.

    Science.gov (United States)

    Maltha, Jessica; Gillet, Philippe; Heutmekers, Marloes; Bottieau, Emmanuel; Van Gompel, Alfons; Jacobs, Jan

    2013-01-01

    In the past malaria rapid diagnostic tests (RDTs) for self-diagnosis by travelers were considered suboptimal due to poor performance. Nowadays RDTs for self-diagnosis are marketed and available through the internet. The present study assessed RDT products marketed for self-diagnosis for diagnostic accuracy and quality of labeling, content and instructions for use (IFU). Diagnostic accuracy of eight RDT products was assessed with a panel of stored whole blood samples comprising the four Plasmodium species (n = 90) as well as Plasmodium negative samples (n = 10). IFUs were assessed for quality of description of procedure and interpretation and for lay-out and readability level. Errors in packaging and content were recorded. Two products gave false-positive test lines in 70% and 80% of Plasmodium negative samples, precluding their use. Of the remaining products, 4/6 had good to excellent sensitivity for the diagnosis of Plasmodium falciparum (98.2%-100.0%) and Plasmodium vivax (93.3%-100.0%). Sensitivity for Plasmodium ovale and Plasmodium malariae diagnosis was poor (6.7%-80.0%). All but one product yielded false-positive test lines after reading beyond the recommended reading time. Problems with labeling (not specifying target antigens (n = 3), and content (desiccant with no humidity indicator (n = 6)) were observed. IFUs had major shortcomings in description of test procedure and interpretation, poor readability and lay-out and user-unfriendly typography. Strategic issues (e.g. the need for repeat testing and reasons for false-negative tests) were not addressed in any of the IFUs. Diagnostic accuracy of RDTs for self-diagnosis was variable, with only 4/8 RDT products being reliable for the diagnosis of P. falciparum and P. vivax, and none for P. ovale and P. malariae. RDTs for self-diagnosis need improvements in IFUs (content and user-friendliness), labeling and content before they can be considered for self-diagnosis by the traveler.

  19. Sensitivity of fecal occult blood testing in the cat.

    Science.gov (United States)

    Rudinsky, Adam J; Guillaumin, Julien; Gilor, Chen

    2017-06-01

    Objectives The impact of dietary factors on fecal occult blood (FOB) testing has been previously evaluated in cats, but the analytical sensitivity of this point-of-care test remains unexamined. The primary goal of this study was to assess the analytical sensitivity of the FOB test in cats. Methods Five cats were used in a repeated measures study. Following oral administration of blood, feces were collected and tested every 12 h for FOB and melena. All cats were fed an animal protein-free diet starting the week before entry into the study. Blood was administered on a milligram of hemoglobin per kilogram of body weight basis, and dosed at 1.5, 3, 15, 30 and 45 mg/kg hemoglobin in series with a wash-out period between each trial. Results FOB was detected in one cat at 1.5 mg/kg hemoglobin, three cats at 3 mg/kg hemoglobin and in all five cats at 15, 30 and 45 mg/kg hemoglobin. Melena was noted in one cat at 30 mg/kg and four cats at 45 mg/kg, but not at lower doses. Conclusions and relevance Administration of 15 mg/kg hemoglobin (equivalent to about 1.5 ml blood) was sufficient for positive results in all cats. However, detection occurred with as little as 1.5 mg/kg hemoglobin. Thus, FOB has good analytical sensitivity in cats under appropriate clinical situations.

  20. Sensitivity analysis of LOFT L2-5 test calculations

    International Nuclear Information System (INIS)

    Prosek, Andrej

    2014-01-01

    The uncertainty quantification of best-estimate code predictions is typically accompanied by a sensitivity analysis, in which the influence of the individual contributors to uncertainty is determined. The objective of this study is to demonstrate the improved fast Fourier transform based method by signal mirroring (FFTBM-SM) for the sensitivity analysis. The sensitivity study was performed for the LOFT L2-5 test, which simulates the large break loss of coolant accident. There were 14 participants in the BEMUSE (Best Estimate Methods-Uncertainty and Sensitivity Evaluation) programme, each performing a reference calculation and 15 sensitivity runs of the LOFT L2-5 test. The important input parameters varied were break area, gap conductivity, fuel conductivity, decay power etc. For the influence of input parameters on the calculated results the FFTBM-SM was used. The only difference between FFTBM-SM and original FFTBM is that in the FFTBM-SM the signals are symmetrized to eliminate the edge effect (the so called edge is the difference between the first and last data point of one period of the signal) in calculating average amplitude. It is very important to eliminate unphysical contribution to the average amplitude, which is used as a figure of merit for input parameter influence on output parameters. The idea is to use reference calculation as 'experimental signal', 'sensitivity run' as 'calculated signal', and average amplitude as figure of merit for sensitivity instead for code accuracy. The larger is the average amplitude the larger is the influence of varied input parameter. The results show that with FFTBM-SM the analyst can get good picture of the contribution of the parameter variation to the results. They show when the input parameters are influential and how big is this influence. FFTBM-SM could be also used to quantify the influence of several parameter variations on the results. However, the influential parameters could not be

  1. Compounding diagnostic delays: a qualitative study of point-of-care testing in South Africa.

    Science.gov (United States)

    Engel, Nora; Davids, Malika; Blankvoort, Nadine; Pai, Nitika Pant; Dheda, Keertan; Pai, Madhukar

    2015-04-01

    Successful point-of-care (POC) testing (completion of test-and-treat cycle in one patient encounter) has immense potential to reduce diagnostic and treatment delays, and improve patient and public health outcomes. We explored what tests are done and how in public/private, rural/urban hospitals and clinics in South Africa and whether they can ensure successful POC testing. This qualitative research study examined POC testing across major diseases in Cape Town, Durban and Eastern Cape. We conducted 101 semi-structured interviews and seven focus group discussions with doctors, nurses, community health workers, patients, laboratory technicians, policymakers, hospital managers and diagnostic manufacturers. In South Africa, diagnostics are characterised by a centralised system. Most tests conducted on the spot can be made to work successfully as POC tests. The majority of public/private clinics and smaller hospitals send samples via couriers to centralised laboratories and retrieve results the same way, via internet, fax or phone. The main challenge to POC testing lies in transporting samples and results, while delays risk patient loss from diagnostic/treatment pathways. Strategies to deal with associated delays create new problems, such as artificially prolonged turnaround times, strains on human resources and quality of testing, compounding additional diagnostic and treatment delays. For POC testing to succeed, particular characteristics of diagnostic ecosystems and adaptations of professional practices to overcome associated challenges must be taken into account. © 2014 John Wiley & Sons Ltd.

  2. The diagnostic value and performance evaluation of five serological tests for the detection of Treponema pallidum.

    Science.gov (United States)

    Liu, Can; Ou, Qishui; Chen, Huijuan; Chen, Jing; Lin, Sheng; Jiang, Ling; Yang, Bin

    2014-05-01

    Syphilis is caused by the bacterium Treponema pallidum (TP). The aim of this study was to establish a clinical approach for serodiagnosis of syphilis by evaluating the performance and diagnostic value of five serological tests for the detection of TP. Five tests were used to test the serum from syphilis patients and control patients, namely rapid plasma reagin (RPR) test, toluidine red unheated serum test (TRUST), TP passive particle agglutination assay (TPPA), TP-specific enzyme-linked immunosorbent assay (TP-ELISA), and TP-specific chemiluminescent immunoassay (TP-CMIA). The sensitivity and diagnostic efficiency of TPPA (96.25%/98.38%), TP-ELISA (100%/95.41%), and TP-CMIA (100%/94.86%) were significantly higher than that of RPR (73.13%/86.22%) and TRUST (73.75%/86.49%) (P < 0.05). The minimum detectable concentrations for the five tests were 30 mIU/ml, 20 mIU/ml, 15 mIU/ml, 150 mIU/ml, and 150 mIU/ml, respectively. According to receiver operating characteristic (ROC) curve, the optimal cut-off values for syphilis diagnosis by TP-CMIA and TP-ELISA were 2.2 and 2.0 S/CO (where S/CO = Sample/calibrator cut off), and the area under the ROC curve (AUC) were 0.998 for TP-CMIA and 0.999 for TP-ELISA. The titers/positive rates for RPR and TRUST dropped from 1:4 (100%) to 1:1 (23.3%) (both P < 0.05) after treatment. However, there were no significant differences when we compared the positive rate of syphilis patients before and after treatment by TPPA, TP-ELISA, and TP-CMIA. Treponemal tests, such as TPPA, TP-ELISA, and TP-CMIA, are recommended for clinical routine screening of syphilis. However, nontreponemal tests, for example, RPR and TRUST, perform better in therapy response assessment. Serological test should be tailored to respective facilities and clinical demands. © 2014 Wiley Periodicals, Inc.

  3. Sensitivity of the luminol test with blue denim.

    Science.gov (United States)

    Middlestead, Caitlyn; Thornton, John

    2010-09-01

    An article appearing in this journal in 2000 suggested that the sensitivity of the luminol test performed on denim fabric is usually no greater than at a 1:100 dilution of blood. This study shows that the luminol test may be unambiguously interpreted at substantially greater dilutions of blood. In this study, four different types of denim were tested by spraying a swatch of fabric with a typical formulation of the luminol reagent. Testing was conducted of dilutions of blood up to 1:1000, all of which showed distinct chemiluminescence. Diluted blood was applied to denim material in the form of a random number. A successful test was obtained only when a "blind" observer, i.e., an observer who was uninformed of the number, correctly reported the number. © 2010 American Academy of Forensic Sciences.

  4. Revisiting the Role of Potassium Sensitivity Testing and Cystoscopic Hydrodistention for the Diagnosis of Interstitial Cystitis

    Science.gov (United States)

    Jiang, Yuan-Hong; Jhang, Jia-Fong; Kuo, Hann-Chorng

    2016-01-01

    Objectives To revisit the diagnostic roles of cystoscopic hydrodistention and the potassium sensitivity test (PST) for the diagnosis of interstitial cystitis (IC). Methods We prospectively enrolled 214 patients clinically diagnosed with IC, 125 non-IC patients who underwent video urodynamic studies and PST, and another 144 non-IC patients who underwent cystoscopic hydrodistention before transurethral surgery. The sensitivity, specificity, and positive and negative predictive values were calculated for the PST and glomerulations after cystoscopic hydrodistention. Results After cystoscopic hydrodistention, glomerulations developed in 211/214 (98.6%) IC patients and 61/144 (42.4%) of the non-IC patients including patients with stones (45/67, 67%), hematuria (2/5, 40%), and stress urinary incontinence (SUI) (6/17, 35%). When positive glomerulation was defined as grade 2 or more, the sensitivity was 61.7%. The PST was positive in 183/214 (85.5%) IC patients and 7/17 (41%) with hypersensitive bladder, 7/32 (22%) with detrusor overactivity, 5/27 (18%) with SUI, 2/21 (10%) with lower urinary tract symptoms, and 2/25 (8%) with bladder outlet obstruction. The PST had a sensitivity of 85.5% and a specificity of 81.6% for diagnosis of IC. IC patients with a positive PST had a significantly smaller urgency sensation capacity, smaller voided volume, and greater bladder pain score. Conclusions Both the PST and glomerulations after hydrodistention are sensitive indicators of IC, but the specificity of glomerulations in the diagnosis of IC is lower than that of the PST. A positive PST is associated with a more hypersensitive bladder and bladder pain, but not the grade of glomerulations in IC patients. Neither test provided 100% diagnostic accuracy for IC, we might select patients into different subgroups based on different PST and hydrodistention results, not for making a diagnosis of IC but for guidance of different treatments. PMID:26999787

  5. Revisiting the Role of Potassium Sensitivity Testing and Cystoscopic Hydrodistention for the Diagnosis of Interstitial Cystitis.

    Directory of Open Access Journals (Sweden)

    Yuan-Hong Jiang

    Full Text Available To revisit the diagnostic roles of cystoscopic hydrodistention and the potassium sensitivity test (PST for the diagnosis of interstitial cystitis (IC.We prospectively enrolled 214 patients clinically diagnosed with IC, 125 non-IC patients who underwent video urodynamic studies and PST, and another 144 non-IC patients who underwent cystoscopic hydrodistention before transurethral surgery. The sensitivity, specificity, and positive and negative predictive values were calculated for the PST and glomerulations after cystoscopic hydrodistention.After cystoscopic hydrodistention, glomerulations developed in 211/214 (98.6% IC patients and 61/144 (42.4% of the non-IC patients including patients with stones (45/67, 67%, hematuria (2/5, 40%, and stress urinary incontinence (SUI (6/17, 35%. When positive glomerulation was defined as grade 2 or more, the sensitivity was 61.7%. The PST was positive in 183/214 (85.5% IC patients and 7/17 (41% with hypersensitive bladder, 7/32 (22% with detrusor overactivity, 5/27 (18% with SUI, 2/21 (10% with lower urinary tract symptoms, and 2/25 (8% with bladder outlet obstruction. The PST had a sensitivity of 85.5% and a specificity of 81.6% for diagnosis of IC. IC patients with a positive PST had a significantly smaller urgency sensation capacity, smaller voided volume, and greater bladder pain score.Both the PST and glomerulations after hydrodistention are sensitive indicators of IC, but the specificity of glomerulations in the diagnosis of IC is lower than that of the PST. A positive PST is associated with a more hypersensitive bladder and bladder pain, but not the grade of glomerulations in IC patients. Neither test provided 100% diagnostic accuracy for IC, we might select patients into different subgroups based on different PST and hydrodistention results, not for making a diagnosis of IC but for guidance of different treatments.

  6. Systematic review, meta-analysis and economic modelling of molecular diagnostic tests for antibiotic resistance in tuberculosis.

    Science.gov (United States)

    Drobniewski, Francis; Cooke, Mary; Jordan, Jake; Casali, Nicola; Mugwagwa, Tendai; Broda, Agnieszka; Townsend, Catherine; Sivaramakrishnan, Anand; Green, Nathan; Jit, Mark; Lipman, Marc; Lord, Joanne; White, Peter J; Abubakar, Ibrahim

    2015-01-01

    economic model was used to evaluate the cost-effectiveness of introducing rapid molecular testing (in addition to culture and drug sensitivity testing). Probabilistic sensitivity analysis was performed to evaluate the impact on cost-effectiveness of diagnostic and treatment time delays, diagnosis and treatment costs, and associated QALYs. RESULTS A total of 8922 titles and abstracts were identified, with 557 papers being potentially eligible. Of these, 56 studies contained sufficient test information for analysis. All three commercial tests performed well when detecting drug resistance in clinical samples, although with evidence of heterogeneity between studies. Pooled sensitivity for GenoType® MTBDRplus (Hain Lifescience, Nehren, Germany) (isoniazid and rifampicin resistance), INNO-LiPA Rif.TB® (Fujirebio Europe, Ghent, Belgium) (rifampicin resistance) and Xpert® MTB/RIF (Cepheid Inc., Sunnyvale, CA, USA) (rifampicin resistance) was 83.4%, 94.6%, 95.4% and 96.8%, respectively; equivalent pooled specificity was 99.6%, 98.2%, 99.7% and 98.4%, respectively. Results of the transmission model suggest that all of the rapid assays considered here, if added to the current diagnostic pathway, would be cost-saving and achieve a reduction in expected QALY loss compared with current practice. GenoType MTBDRplus appeared to be the most cost-effective of the rapid tests in the South Asian population, although results were similar for GeneXpert. In all other scenarios GeneXpert appeared to be the most cost-effective strategy. CONCLUSIONS Rapid molecular tests for rifampicin and isoniazid resistance were sensitive and specific. They may also be cost-effective when added to culture drug susceptibility testing in the UK. There is global interest in point-of-care testing and further work is needed to review the performance of emerging tests and the wider health-economic impact of decentralised testing in clinics and primary care, as well as non-health-care settings, such as shelters and

  7. Systematic review, meta-analysis and economic modelling of molecular diagnostic tests for antibiotic resistance in tuberculosis.

    Science.gov (United States)

    Drobniewski, Francis; Cooke, Mary; Jordan, Jake; Casali, Nicola; Mugwagwa, Tendai; Broda, Agnieszka; Townsend, Catherine; Sivaramakrishnan, Anand; Green, Nathan; Jit, Mark; Lipman, Marc; Lord, Joanne; White, Peter J; Abubakar, Ibrahim

    2015-05-01

    introducing rapid molecular testing (in addition to culture and drug sensitivity testing). Probabilistic sensitivity analysis was performed to evaluate the impact on cost-effectiveness of diagnostic and treatment time delays, diagnosis and treatment costs, and associated QALYs. A total of 8922 titles and abstracts were identified, with 557 papers being potentially eligible. Of these, 56 studies contained sufficient test information for analysis. All three commercial tests performed well when detecting drug resistance in clinical samples, although with evidence of heterogeneity between studies. Pooled sensitivity for GenoType® MTBDRplus (Hain Lifescience, Nehren, Germany) (isoniazid and rifampicin resistance), INNO-LiPA Rif.TB® (Fujirebio Europe, Ghent, Belgium) (rifampicin resistance) and Xpert® MTB/RIF (Cepheid Inc., Sunnyvale, CA, USA) (rifampicin resistance) was 83.4%, 94.6%, 95.4% and 96.8%, respectively; equivalent pooled specificity was 99.6%, 98.2%, 99.7% and 98.4%, respectively. Results of the transmission model suggest that all of the rapid assays considered here, if added to the current diagnostic pathway, would be cost-saving and achieve a reduction in expected QALY loss compared with current practice. GenoType MTBDRplus appeared to be the most cost-effective of the rapid tests in the South Asian population, although results were similar for GeneXpert. In all other scenarios GeneXpert appeared to be the most cost-effective strategy. Rapid molecular tests for rifampicin and isoniazid resistance were sensitive and specific. They may also be cost-effective when added to culture drug susceptibility testing in the UK. There is global interest in point-of-care testing and further work is needed to review the performance of emerging tests and the wider health-economic impact of decentralised testing in clinics and primary care, as well as non-health-care settings, such as shelters and prisons. This study is registered as PROSPERO CRD42011001537. The National Institute

  8. Pediatric Cardiac Anamnesis: Prevention of Additional Diagnostic Tests.

    Science.gov (United States)

    Masic, Izet; Begic, Zijo; Naser, Nabil; Begic, Edin

    2018-01-01

    Pediatrics is defined as the science of a healthy and sick child from birth to end of adolescence. Diseases of the cardiovascular system are the leading causes of mortality in adults, with frequent onset in childhood. The cardiologic examination starts with anamnesis in a pleasant atmosphere, refined space, enough time and patience, detailed measurements, and preferably a noncrying child. Anamnesis, regardless of the development of diagnostic procedures, still constitutes the basis of every clinical examination. The basic characteristics of pediatric cardiac anamnesis are comprehensiveness, that is, details, clarity, concurrency, and chronology. Proper and conscientiously taken anamnesis with a thorough clinical examination of a sick child is a solid protection against dehumanizing the relationship between a physician and patient. Pediatric cardiac anamnesis can be variable, completely negative, but very rich. Anamnesis should, first of all, clarify whether only a child is sick or it is perceived like that be his or her environment. Preschool and school-age children are normally attending anamnesis. High-quality, comprehensive medical history can keep the patient at one level of health care, with a strict focus primarily on the diagnostic processes, reduce crowds in specialist and subspecialist institutions, and make economic savings. A large number of patients in specialist and subspecialist clinics can be reduced by proper screening and by developing primary health-care system (from the local health-care center). Taking patient's medical history with thoroughness has a strong educative character for young doctors at the beginning of their careers.

  9. Comparative analysis of diagnostic performance, feasibility and cost of different test-methods for thyroid nodules with indeterminate cytology.

    Science.gov (United States)

    Sciacchitano, Salvatore; Lavra, Luca; Ulivieri, Alessandra; Magi, Fiorenza; De Francesco, Gian Paolo; Bellotti, Carlo; Salehi, Leila B; Trovato, Maria; Drago, Carlo; Bartolazzi, Armando

    2017-07-25

    Since it is impossible to recognize malignancy at fine needle aspiration (FNA) cytology in indeterminate thyroid nodules, surgery is recommended for all of them. However, cancer rate at final histology is blood assay.We performed systematic reviews and meta-analyses to compare their features, feasibility, diagnostic performance and cost. GEC, GEC+BRAF, M/F panel+miRNA GEC and M/F panel by NGS were the best in ruling-out malignancy (sensitivity = 90%, 89%, 89% and 90% respectively). BRAF and M/F panel alone and by NGS were the best in ruling-in malignancy (specificity = 100%, 93% and 93%). The M/F by NGS showed the highest accuracy (92%) and BRAF the highest diagnostic odds ratio (DOR) (247). GAL-3-ICC performed well as rule-out (sensitivity = 83%) and rule-in test (specificity = 85%), with good accuracy (84%) and high DOR (27) and is one of the cheapest (113 USD) and easiest one to be performed in different clinical settings.In conclusion, the more accurate molecular-based test-methods are still expensive and restricted to few, highly specialized and centralized laboratories. GAL-3-ICC, although limited by some false negatives, represents the most suitable screening test-method to be applied on a large-scale basis in the diagnostic algorithm of indeterminate thyroid lesions.

  10. Using Meta-Analysis to Inform the Design of Subsequent Studies of Diagnostic Test Accuracy

    Science.gov (United States)

    Hinchliffe, Sally R.; Crowther, Michael J.; Phillips, Robert S.; Sutton, Alex J.

    2013-01-01

    An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial…

  11. In Search of Optimal Cognitive Diagnostic Model(s) for ESL Grammar Test Data

    Science.gov (United States)

    Yi, Yeon-Sook

    2017-01-01

    This study compares five cognitive diagnostic models in search of optimal one(s) for English as a Second Language grammar test data. Using a unified modeling framework that can represent specific models with proper constraints, the article first fit the full model (the log-linear cognitive diagnostic model, LCDM) and investigated which model…

  12. Comparison of the sensitivities of the Buehler test and the guinea pig maximization test for predictive testing of contact allergy

    DEFF Research Database (Denmark)

    Frankild, S; Vølund, A; Wahlberg, J E

    2001-01-01

    International test guidelines, such as the Organisation for Economic Cooperation and Development (OECD) guideline #406, recommend 2 guinea pig methods for testing of the contact allergenic potential of chemicals: the Guinea Pig Maximization Test (GPMT) and the Buehler test. Previous comparisons...... between the methods suggested that the Buehler test was less sensitive than the GPMT although modified Buehler test protocols were used. Parallel GPMT and Buehler tests were conducted according to OECD guideline #406 using a multiple-dose design and test results were analysed using a standard logistic...... dose-response model. To compare the sensitivity of the 2 test procedures the test conditions were kept identical and the following chemicals with a range of sensitization potentials were tested: chloraniline, chlorhexidine, eugenol, formaldehyde, mercaptobenzothiazole and neomycin sulphate...

  13. COMPARATIVE EFFICIENCY OF SOME INDIRECT DIAGNOSTIC TESTS FOR THE DETECTION OF SUB-CLINICAL MASTITIS IN COWS AND BUFFALOES

    Directory of Open Access Journals (Sweden)

    M. IQBAL, M. AMJED1, M. A. KHAN, M. S. QURESHI1 AND U. SADIQUE1

    2006-04-01

    Full Text Available The present study was undertaken to compare five laboratory diagnostic tests for sub-clinical mastitis in cattle and buffaloes and to compute cost, time taken by each test and its ranking for availability, adoptability, interpretability and sensitivity. There were 352 cases with each test type viz. California Mastitis Test (CMT, White Side Test (WST, White Side + Dye (WSTD, Surf Test and Surf + Dye, and 880 cases with each species type (cattle and buffaloes. Result scores (1760 for sub-clinical mastitis in each category of negative, trace, single positive, double positive and triple positive by species, and laboratory tests, were analyzed using nonparametric tests. Chi-square statistics showed that CMT was equally effective at both locations (farm vs. laboratory. Correlation further suggested that the association was highly significant. Moreover, cases in category of negative, trace and single positive strongly differed (P0.05. The study further suggested that CMT was the most sensitive test, followed by WST/WSTD and Surf/Surf + Dye. Although, the five tests showed slight discrepancy in the trace category reaction, a strong relationship of Surf Test to CMT, its low cost, easy availability and readily adoptable qualities should spur the relevant authorities to recommend the use of Surf test as a routine practice in dairy farming and add this test in the curriculum of diploma and degree programmes.

  14. Is Serial Testing Required to Diagnose Imported Malaria in the Era of Rapid Diagnostic Tests?

    Science.gov (United States)

    Pasricha, Janet M.; Juneja, Surender; Manitta, Joseph; Whitehead, Susan; Maxwell, Ellen; Goh, Wai-Keong; Pasricha, Sant-Rayn; Eisen, Damon P.

    2013-01-01

    Exclusion of malaria traditionally requires three negative serial thick and thin blood films. However, many clinical laboratories now routinely perform rapid diagnostic tests (RDTs) in addition to blood films when malaria is suspected. We sought to determine whether serial testing is necessary in this setting. We examined 388 cases of malaria diagnosed during 1999–2010 at three laboratories in Melbourne, Australia. For each case, we ascertained whether the diagnosis was made on initial or follow-up testing. Nine cases (3.5%) were diagnosed after a negative initial blood film and RDT: 7 Plasmodium vivax, 1 P. ovale, and 1 P. falciparum. Of four case-patients with P. vivax in which clinical data were available, all had recent exposure to antimalarial medication. Our data suggest that among patients who have not received recent anti-malarial therapy, and when RDTs are performed and blood films are prepared, most malaria diagnoses are made by using the first set of tests. PMID:23208885

  15. Evaluation of the effect of presence of blood in the stomach on endoscopic diagnostic tests for Helicobacter pylori infection

    Directory of Open Access Journals (Sweden)

    S Mittal

    2011-01-01

    Full Text Available Introduction: Presence of blood in the stomach has been thought to affect the performance of diagnostic tests used in detecting Helicobacter pylori (H. pylori in the stomach. This study evaluated the effect of blood on the efficacy of rapid urease test (RUT and microscopic appearance of the biopsy after staining with Giemsa stain. Materials and Methods: Patients with bleeding oesophageal varices who met the inclusion criteria were tested for H. pylori by RUT and microscopic examination of the biopsy. A repeat endoscopy, RUT and histology were done one month following initial presentation. The performance of the diagnostic tests was evaluated with and without the presence of intraluminal blood. A combined result of the two tests, RUT and histology, carried out in presence or absence of blood for the diagnosis of H. pylori, when considered together was considered as the gold standard. Results: Thirty six patients included in the study were in the ages ranging between 15-60 years (mean age = 44.14 years ±2.1. The combination of tests at both visits showed 20/36 (55.6% patients were positive for H. pylori. The decrease in H. pylori positivity in the presence of blood was significant for RUT (8.3% vs. 38.9%; P=0.005 and combined test (19.4% vs. 47.2%; P=0.02 but the decrease in positivity for histology (11.1% vs 30.6% was not significant (P=0.08. In the presence of blood, the sensitivity of RUT, histology and combined tests were 15%, 20% and 35%, respectively. In the absence of blood, the sensitivity of RUT, histology and combination of tests was 70%, 55% and 85%, respectively. Conclusion: Blood in the stomach significantly decreased the sensitivity of RUT, histology and the combination of both. Negative results of these tests in acute upper gastro intestinal (GI bleeding should therefore be interpreted carefully.

  16. Evaluating the accuracy of molecular diagnostic testing for canine visceral leishmaniasis using latent class analysis.

    Directory of Open Access Journals (Sweden)

    Manuela da Silva Solcà

    Full Text Available Host tissues affected by Leishmania infantum have differing degrees of parasitism. Previously, the use of different biological tissues to detect L. infantum DNA in dogs has provided variable results. The present study was conducted to evaluate the accuracy of molecular diagnostic testing (qPCR in dogs from an endemic area for canine visceral leishmaniasis (CVL by determining which tissue type provided the highest rate of parasite DNA detection. Fifty-one symptomatic dogs were tested for CVL using serological, parasitological and molecular methods. Latent class analysis (LCA was performed for accuracy evaluation of these methods. qPCR detected parasite DNA in 100% of these animals from at least one of the following tissues: splenic and bone marrow aspirates, lymph node and skin fragments, blood and conjunctival swabs. Using latent variable as gold standard, the qPCR achieved a sensitivity of 95.8% (CI 90.4-100 in splenic aspirate; 79.2% (CI 68-90.3 in lymph nodes; 77.3% (CI 64.5-90.1 in skin; 75% (CI 63.1-86.9 in blood; 50% (CI 30-70 in bone marrow; 37.5% (CI 24.2-50.8 in left-eye; and 29.2% (CI 16.7-41.6 in right-eye conjunctival swabs. The accuracy of qPCR using splenic aspirates was further evaluated in a random larger sample (n = 800, collected from dogs during a prevalence study. The specificity achieved by qPCR was 76.7% (CI 73.7-79.6 for splenic aspirates obtained from the greater sample. The sensitivity accomplished by this technique was 95% (CI 93.5-96.5 that was higher than those obtained for the other diagnostic tests and was similar to that observed in the smaller sampling study. This confirms that the splenic aspirate is the most effective type of tissue for detecting L. infantum infection. Additionally, we demonstrated that LCA could be used to generate a suitable gold standard for comparative CVL testing.

  17. Hydrocoin level 3 - Testing methods for sensitivity/uncertainty analysis

    International Nuclear Information System (INIS)

    Grundfelt, B.; Lindbom, B.; Larsson, A.; Andersson, K.

    1991-01-01

    The HYDROCOIN study is an international cooperative project for testing groundwater hydrology modelling strategies for performance assessment of nuclear waste disposal. The study was initiated in 1984 by the Swedish Nuclear Power Inspectorate and the technical work was finalised in 1987. The participating organisations are regulatory authorities as well as implementing organisations in 10 countries. The study has been performed at three levels aimed at studying computer code verification, model validation and sensitivity/uncertainty analysis respectively. The results from the first two levels, code verification and model validation, have been published in reports in 1988 and 1990 respectively. This paper focuses on some aspects of the results from Level 3, sensitivity/uncertainty analysis, for which a final report is planned to be published during 1990. For Level 3, seven test cases were defined. Some of these aimed at exploring the uncertainty associated with the modelling results by simply varying parameter values and conceptual assumptions. In other test cases statistical sampling methods were applied. One of the test cases dealt with particle tracking and the uncertainty introduced by this type of post processing. The amount of results available is substantial although unevenly spread over the test cases. It has not been possible to cover all aspects of the results in this paper. Instead, the different methods applied will be illustrated by some typical analyses. 4 figs., 9 refs

  18. Improving diagnostic sensitivity of combined dermoscopy and reflectance confocal microscopy imaging through double reader concordance evaluation in telemedicine settings: A retrospective study of 1000 equivocal cases.

    Directory of Open Access Journals (Sweden)

    A M Witkowski

    Full Text Available Reflectance confocal microscopy (RCM is an imaging device that permits non-invasive visualization of cellular morphology and has been shown to improve diagnostic accuracy of dermoscopically equivocal cutaneous lesions. The application of double reader concordance evaluation of dermoscopy-RCM image sets in retrospective settings and its potential application to telemedicine evaluation has not been tested in a large study population.To improve diagnostic sensitivity of RCM image diagnosis using a double reader concordance evaluation approach; to reduce mismanagement of equivocal cutaneous lesions in retrospective consultation and telemedicine settings.1000 combined dermoscopy-RCM image sets were evaluated in blind by 10 readers with advanced training and internship in dermoscopy and RCM evaluation. We compared sensitivity and specificity of single reader evaluation versus double reader concordance evaluation as well as the effect of diagnostic confidence on lesion management in a retrospective setting.Single reader evaluation resulted in an overall sensitivity of 95.2% and specificity of 76.3%, with misdiagnosis of 8 melanomas, 4 basal cell carcinomas and 2 squamous cell carcinomas. Combined double reader evaluation resulted in an overall sensitivity of 98.3% and specificity of 65.5%, with misdiagnosis of 1 in-situ melanoma and 2 basal cell carcinomas.Evaluation of dermoscopy-RCM image sets of cutaneous lesions by single reader evaluation in retrospective settings is limited by sensitivity levels that may result in potential mismanagement of malignant lesions. Double reader blind concordance evaluation may improve the sensitivity of diagnosis and management safety. The use of a second check can be implemented in telemedicine settings where expert consultation and second opinions may be required.

  19. Association of hip pain with radiographic evidence of hip osteoarthritis: diagnostic test study

    Science.gov (United States)

    Nevitt, Michael C; Niu, Jingbo; Clancy, Mary M; Lane, Nancy E; Link, Thomas M; Vlad, Steven; Tolstykh, Irina; Jungmann, Pia M.; Felson, David T; Guermazi, Ali

    2015-01-01

    Study question Is there concordance between hip pain and radiographic hip osteoarthritis? Methods In this diagnostic test study, pelvic radiographs were assessed for hip osteoarthritis in two cohorts: the Framingham Osteoarthritis Study (community of Framingham, Massachusetts) and the Osteoarthritis Initiative (a multicenter longitudinal cohort study of osteoarthritis in the United States). Using visual representation of the hip joint, participants reported whether they had hip pain on most days and the location of the pain: anterior, groin, lateral, buttocks, or low back. In the Framingham study, participants with hip pain were also examined for hip pain with internal rotation. The authors analysed the agreement between radiographic hip osteoarthritis and hip pain, and for those with hip pain suggestive of hip osteoarthritis they calculated the sensitivity, specificity, positive predictive value, and negative predictive value of radiographs as the diagnostic test. Study answer and limitations In the Framingham study (n=946), only 15.6% of hips in patients with frequent hip pain showed radiographic evidence of hip osteoarthritis, and 20.7% of hips with radiographic hip osteoarthritis were frequently painful. The sensitivity of radiographic hip osteoarthritis for hip pain localised to the groin was 36.7%, specificity 90.5%, positive predictive value 6.0%, and negative predictive value 98.9%. Results did not differ much for hip pain at other locations or for painful internal rotation. In the Osteoarthritis Initiative study (n=4366), only 9.1% of hips in patients with frequent pain showed radiographic hip osteoarthritis, and 23.8% of hips with radiographic hip osteoarthritis were frequently painful. The sensitivity of definite radiographic hip osteoarthritis for hip pain localised to the groin was 16.5%, specificity 94.0%, positive predictive value 7.1%, and negative predictive value 97.6%. Results also did not differ much for hip pain at other locations. What this

  20. Value of Routine Dengue Diagnostic Tests in Urine and Saliva Specimens

    Science.gov (United States)

    Andries, Anne-Claire; Duong, Veasna; Ly, Sowath; Cappelle, Julien; Kim, Kim Srorn; Lorn Try, Patrich; Ros, Sopheaktra; Ong, Sivuth; Huy, Rekol; Horwood, Paul; Flamand, Marie; Sakuntabhai, Anavaj; Tarantola, Arnaud; Buchy, Philippe

    2015-01-01

    Background Dengue laboratory diagnosis is essentially based on detection of the virus, its components or antibodies directed against the virus in blood samples. Blood, however, may be difficult to draw in some patients, especially in children, and sampling during outbreak investigations or epidemiological studies may face logistical challenges or limited compliance to invasive procedures from subjects. The aim of this study was to assess the possibility of using saliva and urine samples instead of blood for dengue diagnosis. Methodology/Principal Findings Serial plasma, urine and saliva samples were collected at several time-points between the day of admission to hospital until three months after the onset of fever in children with confirmed dengue disease. Quantitative RT-PCR, NS1 antigen capture and ELISA serology for anti-DENV antibody (IgG, IgM and IgA) detection were performed in parallel on the three body fluids. RT-PCR and NS1 tests demonstrated an overall sensitivity of 85.4%/63.4%, 41.6%/14.5% and 39%/28.3%, in plasma, urine and saliva specimens, respectively. When urine and saliva samples were collected at the same time-points and tested concurrently, the diagnostic sensitivity of RNA and NS1 detection assays was 69.1% and 34.4%, respectively. IgG/IgA detection assays had an overall sensitivity of 54.4%/37.4%, 38.5%/26.8% and 52.9%/28.6% in plasma, urine and saliva specimens, respectively. IgM were detected in 38.1% and 36% of the plasma and saliva samples but never in urine. Conclusions Although the performances of the different diagnostic methods were not as good in saliva and urine as in plasma specimens, the results obtained by qRT-PCR and by anti-DENV antibody ELISA could well justify the use of these two body fluids to detect dengue infection in situations when the collection of blood specimens is not possible. PMID:26406240

  1. An assessment of various blood collection and transfer methods used for malaria rapid diagnostic tests

    Directory of Open Access Journals (Sweden)

    Baik Fred

    2007-11-01

    Full Text Available Abstract Background Four blood collection and transfer devices commonly used for malaria rapid diagnostic tests (RDTs were assessed for their consistency, accuracy and ease of use in the hands of laboratory technicians and village health workers. Methods Laboratory technicians and village health workers collected blood from a finger prick using each device in random order, and deposited the blood either on filter paper or into a suitable casette-type RDT. Consistency and accuracy of volume delivered was determined by comparing the measurements of the resulting blood spots/heights with the measurements of laboratory-prepared pipetted standard volumes. The effect of varying blood volumes on RDT sensitivity and ease of use was also observed. Results There was high variability in blood volume collected by the devices, with the straw and the loop, the most preferred devices, usually transferring volumes greater than intended, while the glass capillary tube and the plastic pipette transferring less volume than intended or none at all. Varying the blood volume delivered to RDTs indicated that this variation is critical to RDT sensitivity only when the transferred volume is very low. Conclusion None of the blood transfer devices assessed performed consistently well. Adequate training on their use is clearly necessary, with more development efforts for improved designs to be used by remote health workers, in mind.

  2. Diagnostic test pepsinogen I and combination with tumor marker CEA in gastric cancer

    Science.gov (United States)

    Sembiring, J.; Sarumpaet, K.; Ganie, R. A.

    2018-03-01

    Gastric cancer (GC) is the fifth leading cause of cancer and the third leading cause of cancer-related mortality globally. Human pepsinogens (HP) are considered promising serological biomarkers for the screening of atrophic gastritis (AG) and GC. HP are biochemically and immunochemically classified into two groups: pepsinogen I (PG I) and PG II. Carcinoembryonic antigen (CEA) is a glycoprotein, which is present in normal mucosal cells but increased amounts are associated with adenocarcinoma, especially colorectal cancer. CEA in combination with other tumour markers can be used in pre-operative staging and thereby assist in the planning of the type of surgery required and future management options. The purpose of this study was to diagnose test PG I and combination with tumor marker CEA in 32 patients suspected with GC. There was a significant difference in levels of CEA between GC group with non-GC with a value p <0.001. PGI sensitivity was 70.58% and specificity 93.3%. The sensitivity of PGI and CEA combination of 94.1% and specificity 80%. The area of AUC obtained was 92.7% at 95% confidence interval (82.7-100%). This AUC value indicated that the value of diagnostic accuracy of the PGI and CEA combinations of 92.7%.

  3. A diagnostic test for scabies: IgE specificity for a recombinant allergen of Sarcoptes scabiei.

    Science.gov (United States)

    Jayaraj, Rama; Hales, Belinda; Viberg, Linda; Pizzuto, Susan; Holt, Deborah; Rolland, Jennifer M; O'Hehir, Robyn E; Currie, Bart J; Walton, Shelley F

    2011-12-01

    Scabies infestations are difficult to diagnose clinically and current serologic tests have less than 50% accuracy. To develop more reliable diagnosis of scabies, specific IgE antibodies to a major scabies antigen recombinant Sar s 14.3 (rSar s 14.3) were measured in 140 plasma samples from scabies-infested and control subject groups using dissociation-enhanced lanthanide fluorescent immunoassays (DELFIA). Levels of rSar s 14.3-specific IgE were quantified, and cross-reactivity with its house dust mite homologue, Der p 14, was assessed. The rSar s 14.3 DELFIA showed excellent diagnostic capability, with 100% sensitivity and 93.75% specificity for distinguishing subjects with current scabies infestation from control, uninfested subjects. Recombinant Der p 14 preparation was ineffective at inhibiting IgE binding to rSar s 14.3. This study shows that quantification of levels of IgE antibody to rSar s 14.3 is a highly sensitive method for diagnosis of scabies infestation in clinical practice. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Understanding diagnostic plots for well-test interpretation

    OpenAIRE

    Renard, Philippe; Glenz, Damian; Mejias, Miguel

    2009-01-01

    Dans le domaine de l’interprétation des essais de pompage, un graphe de diagnostic est un graphe simultané du rabattement et de sa dérivée logarithmique en fonction du temps. Ce graphe est habituellement représenté en échelle bi-logarithmique. Les avantages principaux et les limites de cet outil sont discutés à l’aide de trois exemples hydrogéologiques réels. Des recommandations pratiques sont proposées afin d’utiliser ces graphes pour sélectionner un modèle conceptuel d’écoulement. Lorsque l...

  5. Diagnostic Testing for Diabetes Using HbA1c in the Abu Dhabi Population

    Science.gov (United States)

    Hajat, Cother; Harrison, Oliver; Al Siksek, Zaid

    2011-01-01

    OBJECTIVE The validity of HbA1c as a population diagnostic tool was tested against oral glucose tolerance testing in Abu Dhabi nationals. RESEARCH DESIGN AND METHODS The screening tool of HbA1c and random glucose was validated against the “gold standard” oral glucose tolerance test according to World Health Organization criteria. RESULTS The HbA1c threshold of 6.4% provided the optimum balance between sensitivity (72.0%) and specificity (84.3%) with positive and negative predictive values of 47.9 and 93.7% and area under the receiver operating characteristics curve of 0.78. This threshold compares with a threshold of 6.5% recommended by the International Scientific Committee and American Diabetes Association and of 6.3% in a recent study in China. CONCLUSIONS This study successfully validates the feasibility and threshold of HbA1c for diagnosis of diabetes at the population level in a Middle-Eastern population. This result is a major step in the fight to tackle the increasing burden of diabetes in the United Arab Emirates. PMID:21926284

  6. Diagnostic yield of genetic testing in epileptic encephalopathy in childhood.

    Science.gov (United States)

    Mercimek-Mahmutoglu, Saadet; Patel, Jaina; Cordeiro, Dawn; Hewson, Stacy; Callen, David; Donner, Elizabeth J; Hahn, Cecil D; Kannu, Peter; Kobayashi, Jeff; Minassian, Berge A; Moharir, Mahendranath; Siriwardena, Komudi; Weiss, Shelly K; Weksberg, Rosanna; Snead, O Carter

    2015-05-01

    Epilepsy is a common neurologic disorder of childhood. To determine the genetic diagnostic yield in epileptic encephalopathy, we performed a retrospective cohort study in a single epilepsy genetics clinic. We included all patients with intractable epilepsy, global developmental delay, and cognitive dysfunction seen between January 2012 and June 2014 in the Epilepsy Genetics Clinic. Electronic patient charts were reviewed for clinical features, neuroimaging, biochemical investigations, and molecular genetic investigations including targeted next-generation sequencing of epileptic encephalopathy genes. Genetic causes were identified in 28% of the 110 patients: 7% had inherited metabolic disorders including pyridoxine dependent epilepsy caused by ALDH7A1 mutation, Menkes disease, pyridox(am)ine-5-phosphate oxidase deficiency, cobalamin G deficiency, methylenetetrahydrofolate reductase deficiency, glucose transporter 1 deficiency, glycine encephalopathy, and pyruvate dehydrogenase complex deficiency; 21% had other genetic causes including genetic syndromes, pathogenic copy number variants on array comparative genomic hybridization, and epileptic encephalopathy related to mutations in the SCN1A, SCN2A, SCN8A, KCNQ2, STXBP1, PCDH19, and SLC9A6 genes. Forty-five percent of patients obtained a genetic diagnosis by targeted next-generation sequencing epileptic encephalopathy panels. It is notable that 4.5% of patients had a treatable inherited metabolic disease. To the best of our knowledge, this is the first study to combine inherited metabolic disorders and other genetic causes of epileptic encephalopathy. Targeted next-generation sequencing panels increased the genetic diagnostic yield from 25% in patients with epileptic encephalopathy. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.

  7. Diagnostic accuracy of five orthopedic clinical tests for diagnosis of superior labrum anterior posterior (SLAP) lesions.

    Science.gov (United States)

    Cook, Chad; Beaty, Stacy; Kissenberth, Michael J; Siffri, Paul; Pill, Stephan G; Hawkins, Richard J

    2012-01-01

    The clinical diagnosis of a superior labral anterior posterior (SLAP) tear is extremely challenging. Most studies that advocate selected tests have errors in study design or significant bias, or both. The purpose of this study was to identify the diagnostic utility of the Active Compression/O'Brien's test, Biceps Load II test, Dynamic Labral Shear test (O'Driscoll's test), Speed's test, and the Labral Tension test when diagnosing isolated SLAP lesions (SLAP-only) and a SLAP lesion with concomitant disorders (eg, rotator cuff tear), as stand-alone and clustered tests, with diagnostic confirmation by arthroscopic surgery. This diagnostic accuracy study was a case-based, case-control design that included 87 individuals with variable shoulder pathology. Of the 5 tests, only the Biceps Load II test demonstrated utility in identifying patients with a SLAP-only lesion, with a positive predictive value of 26 (95% confidence limits [CL], 18, 31), negative predictive value of 93 (95% CL, 84, 97), positive likelihood ratio of 1.7 (95% CL, 1.1, 2.6), and negative likelihood ratio of 0.39 (95% CL, 0.14, 0.91). No tests demonstrated diagnostic utility when diagnosing any SLAP lesion, including those with concomitant diagnoses. No clusters demonstrated better diagnostic accuracy than stand-alone findings. There are a number of potential reasons for the poor utility in the 5 test findings. The heterogeneous sample included patients with a variety of shoulder disorders. The study was organized using very strict methodologic controls that should reduce the risk of bias, which normally overinflates the accuracy of a specific tool. The findings may truly reflect the stand-alone, diagnostic utility of the 5 tests, suggesting when used alone provides little usefulness toward decision making of the diagnostic clinician. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  8. Acrobeads test: a new diagnostic test for assessment of the fertilizing capacity of human spermatozoa.

    Science.gov (United States)

    Ohashi, K; Saji, F; Kato, M; Tsutsui, T; Tomiyama, T; Tanizawa, O

    1995-03-01

    To determine the effectiveness of the Acrobeads test for predicting the outcome of IVF. Human spermatozoa express the CD46 molecule (membrane cofactor protein) on their heads after the acrosome reaction. CD46-positive spermatozoa formed a sperm-bead complex with immunobeads coated with anti-CD46 monoclonal antibody. In the Acrobeads test, fertilizing capacity was determined by assessing sperm-bead agglutination. Department of Obstetrics and Gynecology, Osaka University Hospital. Thirty-seven donors of proven fertility and 88 male partners of infertile couples. We carried out the Acrobeads test and a sperm penetration assay (SPA) using zona-free hamster oocytes within 3 months before IVF and we then analyzed the results in relation to IVF outcome. The sensitivity of the Acrobeads test and SPA was 100% and 88%, respectively, whereas the specificity was 43% and 52%, respectively. The negative predictive value of the Acro-beads test was 100%, whereas that of the SPA was 73%. These results indicate that there was no significant difference between these two tests in terms of predicting IVF outcome. We suggested that the Acrobeads test be used to evaluate the fertilizing capacity of human spermatozoa because we should avoid using the SPA to prevent cruelty to animals.

  9. Field test investigation of high sensitivity fiber optic seismic geophone

    Science.gov (United States)

    Wang, Meng; Min, Li; Zhang, Xiaolei; Zhang, Faxiang; Sun, Zhihui; Li, Shujuan; Wang, Chang; Zhao, Zhong; Hao, Guanghu

    2017-10-01

    Seismic reflection, whose measured signal is the artificial seismic waves ,is the most effective method and widely used in the geophysical prospecting. And this method can be used for exploration of oil, gas and coal. When a seismic wave travelling through the Earth encounters an interface between two materials with different acoustic impedances, some of the wave energy will reflect off the interface and some will refract through the interface. At its most basic, the seismic reflection technique consists of generating seismic waves and measuring the time taken for the waves to travel from the source, reflect off an interface and be detected by an array of geophones at the surface. Compared to traditional geophones such as electric, magnetic, mechanical and gas geophone, optical fiber geophones have many advantages. Optical fiber geophones can achieve sensing and signal transmission simultaneously. With the development of fiber grating sensor technology, fiber bragg grating (FBG) is being applied in seismic exploration and draws more and more attention to its advantage of anti-electromagnetic interference, high sensitivity and insensitivity to meteorological conditions. In this paper, we designed a high sensitivity geophone and tested its sensitivity, based on the theory of FBG sensing. The frequency response range is from 10 Hz to 100 Hz and the acceleration of the fiber optic seismic geophone is over 1000pm/g. sixteen-element fiber optic seismic geophone array system is presented and the field test is performed in Shengli oilfield of China. The field test shows that: (1) the fiber optic seismic geophone has a higher sensitivity than the traditional geophone between 1-100 Hz;(2) The low frequency reflection wave continuity of fiber Bragg grating geophone is better.

  10. Prospective evaluation of the diagnostic value of sensitive KIT D816V mutation analysis of blood in adults with suspected systemic mastocytosis

    DEFF Research Database (Denmark)

    Kielsgaard Kristensen, Thomas; Vestergaard, H; Bindslev-Jensen, C

    2017-01-01

    BACKGROUND: Sensitive KIT D816V mutation analysis of blood has been proposed to guide bone marrow (BM) investigation in suspected systemic mastocytosis (SM). The aim of this prospective study was for the first time to compare the D816V status of the "screening blood sample" used to guide BM biopsy...... in suspected SM to the outcome of the subsequent BM investigation. METHODS: Fifty-eight adult patients with suspected SM were included. The outcome of sensitive KIT D816V analysis of blood was compared to the result of the BM investigation. RESULTS: Screening blood samples from 44 of 58 patients tested D816V...... patients did not fulfill any diagnostic SM criteria (excluding tryptase criterion). Of the 48 SM patients, 90% tested D816V-positive. Thirteen SM patients presented with Hymenoptera venom-induced anaphylaxis, no skin lesions, and baseline serum tryptase ≤20 ng/mL. Of these, 92% tested D816V...

  11. Meningitis Dipstick Rapid Test: Evaluating Diagnostic Performance during an Urban Neisseria meningitidis Serogroup A Outbreak, Burkina Faso, 2007

    Science.gov (United States)

    Rose, Angela M. C.; Mueller, Judith E.; Gerstl, Sibylle; Njanpop-Lafourcade, Berthe-Marie; Page, Anne-Laure; Nicolas, Pierre; Traoré, Ramata Ouédraogo; Caugant, Dominique A.; Guerin, Philippe J.

    2010-01-01

    Meningococcal meningitis outbreaks occur every year during the dry season in the “meningitis belt” of sub-Saharan Africa. Identification of the causative strain is crucial before launching mass vaccination campaigns, to assure use of the correct vaccine. Rapid agglutination (latex) tests are most commonly available in district-level laboratories at the beginning of the epidemic season; limitations include a short shelf-life and the need for refrigeration and good technical skills. Recently, a new dipstick rapid diagnostic test (RDT) was developed to identify and differentiate disease caused by meningococcal serogroups A, W135, C and Y. We evaluated the diagnostic performance of this dipstick RDT during an urban outbreak of meningitis caused by N. meningitidis serogroup A in Ouagadougou, Burkina Faso; first against an in-country reference standard of culture and/or multiplex PCR; and second against culture and/or a highly sensitive nested PCR technique performed in Oslo, Norway. We included 267 patients with suspected acute bacterial meningitis. Using the in-country reference standard, 50 samples (19%) were positive. Dipstick RDT sensitivity (N = 265) was 70% (95%CI 55–82) and specificity 97% (95%CI 93–99). Using culture and/or nested PCR, 126/259 (49%) samples were positive; dipstick RDT sensitivity (N = 257) was 32% (95%CI 24–41), and specificity was 99% (95%CI 95–100). We found dipstick RDT sensitivity lower than values reported from (i) assessments under ideal laboratory conditions (>90%), and (ii) a prior field evaluation in Niger [89% (95%CI 80–95)]. Specificity, however, was similar to (i), and higher than (ii) [62% (95%CI 48–75)]. At this stage in development, therefore, other tests (e.g., latex) might be preferred for use in peripheral health centres. We highlight the value of field evaluations for new diagnostic tests, and note relatively low sensitivity of a reference standard using multiplex vs. nested PCR. Although the former is

  12. Meningitis dipstick rapid test: evaluating diagnostic performance during an urban Neisseria meningitidis serogroup A outbreak, Burkina Faso, 2007.

    Directory of Open Access Journals (Sweden)

    Angela M C Rose

    Full Text Available Meningococcal meningitis outbreaks occur every year during the dry season in the "meningitis belt" of sub-Saharan Africa. Identification of the causative strain is crucial before launching mass vaccination campaigns, to assure use of the correct vaccine. Rapid agglutination (latex tests are most commonly available in district-level laboratories at the beginning of the epidemic season; limitations include a short shelf-life and the need for refrigeration and good technical skills. Recently, a new dipstick rapid diagnostic test (RDT was developed to identify and differentiate disease caused by meningococcal serogroups A, W135, C and Y. We evaluated the diagnostic performance of this dipstick RDT during an urban outbreak of meningitis caused by N. meningitidis serogroup A in Ouagadougou, Burkina Faso; first against an in-country reference standard of culture and/or multiplex PCR; and second against culture and/or a highly sensitive nested PCR technique performed in Oslo, Norway. We included 267 patients with suspected acute bacterial meningitis. Using the in-country reference standard, 50 samples (19% were positive. Dipstick RDT sensitivity (N = 265 was 70% (95%CI 55-82 and specificity 97% (95%CI 93-99. Using culture and/or nested PCR, 126/259 (49% samples were positive; dipstick RDT sensitivity (N = 257 was 32% (95%CI 24-41, and specificity was 99% (95%CI 95-100. We found dipstick RDT sensitivity lower than values reported from (i assessments under ideal laboratory conditions (>90%, and (ii a prior field evaluation in Niger [89% (95%CI 80-95]. Specificity, however, was similar to (i, and higher than (ii [62% (95%CI 48-75]. At this stage in development, therefore, other tests (e.g., latex might be preferred for use in peripheral health centres. We highlight the value of field evaluations for new diagnostic tests, and note relatively low sensitivity of a reference standard using multiplex vs. nested PCR. Although the former is the current standard

  13. Accuracy of Diagnostic Methods and Surveillance Sensitivity for Human Enterovirus, South Korea, 1999–2011

    Science.gov (United States)

    Hyeon, Ji-Yeon; Hwang, Seoyeon; Kim, Hyejin; Song, Jaehyoung; Ahn, Jeongbae; Kang, Byunghak; Kim, Kisoon; Choi, Wooyoung; Chung, Jae Keun; Kim, Cheon-Hyun; Cho, Kyungsoon; Jee, Youngmee; Kim, Jonghyun; Kim, Kisang; Kim, Sun-Hee; Kim, Min-Ji

    2013-01-01

    The epidemiology of enteroviral infection in South Korea during 1999–2011 chronicles nationwide outbreaks and changing detection and subtyping methods used over the 13-year period. Of 14,657 patients whose samples were tested, 4,762 (32.5%) samples were positive for human enterovirus (human EV); as diagnostic methods improved, the rate of positive results increased. A seasonal trend of outbreaks was documented. Genotypes enterovirus 71, echovirus 30, coxsackievirus B5, enterovirus 6, and coxsackievirus B2 were the most common genotypes identified. Accurate test results correlated clinical syndromes to enterovirus genotypes: aseptic meningitis to echovirus 30, enterovirus 6, and coxsackievirus B5; hand, foot and mouth disease to coxsackievirus A16; and hand, foot and mouth disease with neurologic complications to enterovirus 71. There are currently no treatments specific to human EV infections; surveillance of enterovirus infections such as this study provides may assist with evaluating the need to research and develop treatments for infections caused by virulent human EV genotypes. PMID:23876671

  14. Diagnostic accuracy of urine Helicobacter pylori antibody test in junior and senior high school students in Japan.

    Science.gov (United States)

    Mabe, Katushiro; Kikuchi, Shogo; Okuda, Masumi; Takamasa, Mitsuharu; Kato, Mototsugu; Asaka, Masahiro

    2017-02-01

    To prevent gastric cancer, a Helicobacter pylori test-and-treat strategy has been proposed. In Japan, routine urine examinations are performed to screen for kidney diseases; it is therefore convenient to screen for H. pylori infection via urine antibody (u-Ab) testing. To evaluate the diagnostic accuracy of u-Ab testing in students using 13 C-urea breath testing (UBT) as a standard. The study population included 806 junior or senior high school students in Japan who provided urine samples and/or underwent UBT. Students with a positive u-Ab test or discrepant results between the u-Ab test and UBT were asked to provide additional stool and/or blood samples or to repeat the UBT. Urinary protein was detected using a urine test strip. The positive rates for the u-Ab test and UBT were 8.9% (71/795) and 5.5% (44/801), respectively. The u-Ab test showed 88.4% sensitivity and 95.7% specificity using UBT as a standard. In the final diagnoses, the u-Ab test showed 97.6% sensitivity, 96.5% specificity, 61.2% positive predictive value (PPV), and 99.9% negative predictive value (NPV). Of the 508 samples tested using a urine test strip, negative results were obtained for 450 subjects with a sensitivity of 90%, specificity of 97.9%, PPV of 66.7%, and NPV of 99.5%. Proteinuria was detected in 58 samples, with a sensitivity of 100%, specificity of 88.9%, PPV of 40%, and NPV of 100%. The u-Ab test is highly accurate and suitable for detecting H. pylori infection. However, the occurrence of proteinuria may yield false-positive results. © 2016 John Wiley & Sons Ltd.

  15. Allergic bronchopulmonary aspergillosis in Italian cystic fibrosis patients: Prevalence and percentage of positive tests in the employed diagnostic criteria

    International Nuclear Information System (INIS)

    Taccetti, Giovanni; Procopio, Elena; Marianelli, Lore; Campana, Silvia

    2000-01-01

    The prevalence of allergic bronchopulmonary aspergillosis (ABPA) in cystic fibrosis (CF) patients is difficult to determine because the data in the literature are not homogeneous or comparable. ABPA and CF have similar clinical symptoms which make diagnosis difficult and underestimate the real dimensions of the problem. We conducted an epidemiological study on 3089 Italian CF patients to determine the prevalence of ABPA in Italy and verify the percentage of positive tests in the employed diagnostic criteria. Our results indicate that the prevalence of ABPA in Italian CF patients is 6.18%, mainly in adolescents and young adults. ABPA is diagnosed using clinical symptoms (presence of episodic bronchial obstructions or typical radiographic features) and on the basis of other criteria which can only be partially fulfilled in paediatric patients. Among the diagnostic tests the most sensitive are the total IgE (84.5%), specific IgE anti-Aspergillus fumigatus (81.6%) and the prick test (68.3%). In the absence of clinical symptoms and gold standard diagnostic tests, serological positivity and/or the skin test are not sufficient evidence to confirm the presence of ABPA

  16. Design standards for experimental and field studies to evaluate diagnostic accuracy of tests for infectious diseases in aquatic animals.

    Science.gov (United States)

    Laurin, E; Thakur, K K; Gardner, I A; Hick, P; Moody, N J G; Crane, M S J; Ernst, I

    2018-03-15

    Design and reporting quality of diagnostic accuracy studies (DAS) are important metrics for assessing utility of tests used in animal and human health. Following standards for designing DAS will assist in appropriate test selection for specific testing purposes and minimize the risk of reporting biased sensitivity and specificity estimates. To examine the benefits of recommending standards, design information from published DAS literature was assessed for 10 finfish, seven mollusc, nine crustacean and two amphibian diseases listed in the 2017 OIE Manual of Diagnostic Tests for Aquatic Animals. Of the 56 DAS identified, 41 were based on field testing, eight on experimental challenge studies and seven on both. Also, we adapted human and terrestrial-animal standards and guidelines for DAS structure for use in aquatic animal diagnostic research. Through this process, we identified and addressed important metrics for consideration at the design phase: study purpose, targeted disease state, selection of appropriate samples and specimens, laboratory analytical methods, statistical methods and data interpretation. These recommended design standards for DAS are presented as a checklist including risk-of-failure points and actions to mitigate bias at each critical step. Adherence to standards when designing DAS will also facilitate future systematic review and meta-analyses of DAS research literature. © 2018 John Wiley & Sons Ltd.

  17. Optimizing adaptive learning through testing, diagnostic reflection and learner-controlled information selection

    NARCIS (Netherlands)

    Dirkx, Kim; Kester, Liesbeth; Kirschner, Paul A.

    2010-01-01

    Dirkx, K. J. H., Kester, L., & Kirschner, P. A. (2010, 25 February). Optimizing adaptive learning through testing, diagnostic reflection and learner-controlled information selection. Presentation at the Learning & Cognition meeting, Heerlen, The Netherlands: Open University of the Netherlands.

  18. ITER diagnostics: Maintenance and commissioning in the hot cell test bed

    International Nuclear Information System (INIS)

    Walker, C.I.; Barnsley, R.; Costley, A.E.; Gottfried, R.; Haist, B.; Itami, K.; Kondoh, T.; Loesser, G.D.; Palmer, J.; Sugie, T.; Tesini, A.; Vayakis, G.

    2005-01-01

    In-vessel diagnostic equipment in ITER integrated in six equatorial and 12 upper ports, 16 divertor cassettes and five lower ports is designed to be removed in modules and then repaired, tested and commissioned in the same location at the ITER hot cell. The repair requirements and tests on these components are described along with design features that facilitate repair. The testing establishes the repair strategy, qualifies the refurbishment work and finally checks the mechanical and diagnostic function before the return of the modules. At the hot cell, a dummy port is provided for tests of mechanical and vacuum integrity as well as commissioning of the diagnostic equipment. The scope of the hot cell maintenance and commissioning activities is summarised and an overview of the integration of the diagnostic equipment is given

  19. Diagnostic Accuracy of Molecular Amplification Tests for Human African Trypanosomiasis-Systematic Review

    NARCIS (Netherlands)

    Mugasa, Claire M.; Adams, Emily R.; Boer, Kimberly R.; Dyserinck, Heleen C.; Büscher, Philippe; Schallig, Henk D. H. F.; Leeflang, Mariska M. G.

    2012-01-01

    Background: A range of molecular amplification techniques have been developed for the diagnosis of Human African Trypanosomiasis (HAT); however, careful evaluation of these tests must precede implementation to ensure their high clinical accuracy. Here, we investigated the diagnostic accuracy of

  20. Development of diagnostic test instruments to reveal level student conception in kinematic and dynamics

    Science.gov (United States)

    Handhika, J.; Cari, C.; Suparmi, A.; Sunarno, W.; Purwandari, P.

    2018-03-01

    The purpose of this research was to develop a diagnostic test instrument to reveal students' conceptions in kinematics and dynamics. The diagnostic test was developed based on the content indicator the concept of (1) displacement and distance, (2) instantaneous and average velocity, (3) zero and constant acceleration, (4) gravitational acceleration (5) Newton's first Law, (6) and Newton's third Law. The diagnostic test development model includes: Diagnostic test requirement analysis, formulating test-making objectives, developing tests, checking the validity of the content and the performance of reliability, and application of tests. The Content Validation Index (CVI) results in the category are highly relevant, with a value of 0.85. Three questions get negative Content Validation Ratio CVR) (-0.6), after revised distractors and clarify visual presentation; the CVR become 1 (highly relevant). This test was applied, obtained 16 valid test items, with Cronbach Alpha value of 0.80. It can conclude that diagnostic test can be used to reveal the level of students conception in kinematics and dynamics.

  1. BRAF mutation testing with a rapid, fully integrated molecular diagnostics system

    Science.gov (United States)

    Huang, Helen J.; Falchook, Gerald S.; Devogelaere, Benoit; Kockx, Mark; Bempt, Isabelle Vanden; Reijans, Martin; Naing, Aung; Fu, Siqing; Piha-Paul, Sarina A.; Hong, David S.; Holley, Veronica R.; Tsimberidou, Apostolia M.; Stepanek, Vanda M.; Patel, Sapna P.; Kopetz, E. Scott; Subbiah, Vivek; Wheler, Jennifer J.; Zinner, Ralph G.; Karp, Daniel D.; Luthra, Rajyalakshmi; Roy-Chowdhuri, Sinchita; Sablon, Erwin; Meric-Bernstam, Funda; Maertens, Geert; Kurzrock, Razelle

    2015-01-01

    Fast and accurate diagnostic systems are needed for further implementation of precision therapy of BRAF-mutant and other cancers. The novel IdyllaTM BRAF Mutation Test has high sensitivity and shorter turnaround times compared to other methods. We used Idylla to detect BRAF V600 mutations in archived formalin-fixed paraffin-embedded (FFPE) tumor samples and compared these results with those obtained using the cobas 4800 BRAF V600 Mutation Test or MiSeq deep sequencing system and with those obtained by a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory employing polymerase chain reaction–based sequencing, mass spectrometric detection, or next-generation sequencing. In one set of 60 FFPE tumor samples (15 with BRAF mutations per Idylla), the Idylla and cobas results had an agreement of 97%. Idylla detected BRAF V600 mutations in two additional samples. The Idylla and MiSeq results had 100% concordance. In a separate set of 100 FFPE tumor samples (64 with BRAF mutation per Idylla), the Idylla and CLIA-certified laboratory results demonstrated an agreement of 96% even though the tests were not performed simultaneously and different FFPE blocks had to be used for 9 cases. The IdyllaTM BRAF Mutation Test produced results quickly (sample to results time was about 90 minutes with about 2 minutes of hands on time) and the closed nature of the cartridge eliminates the risk of PCR contamination. In conclusion, our observations demonstrate that the Idylla test is rapid and has high concordance with other routinely used but more complex BRAF mutation–detecting tests. PMID:26330075

  2. Evaluation of diagnostic tests for Wuchereria bancrofti infection in Brazilian schoolchildren

    Directory of Open Access Journals (Sweden)

    Paula Oliveira

    2014-06-01

    Full Text Available Introduction Since the launch of the Global Programme to Eliminate Lymphatic Filariasis, more than 70% of the endemic countries have implemented mass drug administration (MDA to interrupt disease transmission. The monitoring of filarial infection in sentinel populations, particularly schoolchildren, is recommended to assess the impact of MDA. A key issue is choosing the appropriate tools for these initial assessments (to define the best intervention and for monitoring transmission. Methods This study compared the pre-MDA performance of five diagnostic methods, namely, thick film test, Knott's technique, filtration, Og4C3-ELISA, and the AD12-ICT card test, in schoolchildren from Brazil. Venous and capillary blood samples were collected between 11 pm and 1 am. The microfilarial loads were analyzed with a negative binomial regression, and the prevalence and associated 95% confidence intervals were estimated for all methods. The accuracies of the AD12-ICT card and Og4C3-ELISA tests were assessed against the combination of parasitological test results. Results A total of 805 schoolchildren were examined. The overall and stratified prevalence by age group and gender detected by Og4C3-ELISA and AD12-ICT were markedly higher than the prevalence estimated by the parasitological methods. The sensitivity of the AD12-ICT card and Og4C3-ELISA tests was approximately 100%, and the positive likelihood ratios were above 6. The specificity of the Og4C3-ELISA was higher than that of the AD12-ICT at different prevalence levels. Conclusions The ICT card test should be the recommended tool for monitoring school-age populations living in areas with ongoing or completed MDA.

  3. Potential diagnostic consequences of applying non-invasive prenatal testing

    DEFF Research Database (Denmark)

    Petersen, O B; Vogel, I; Ekelund, C

    2014-01-01

    OBJECTIVES: Targeted non-invasive prenatal testing (NIPT) tests for trisomies 21, 18 and 13 and sex chromosome aneuploidies and could be an alternative to traditional karyotyping. The aim of this study was to determine the risk of missing other abnormal karyotypes of probable phenotypic...

  4. A systematic review of the diagnostic accuracy of provocative tests of the neck for diagnosing cervical radiculopathy

    Science.gov (United States)

    Pool, Jan J. M.; van Tulder, Maurits W.; Riphagen, Ingrid I.; de Vet, Henrica C. W.

    2006-01-01

    Clinical provocative tests of the neck, which position the neck and arm inorder to aggravate or relieve arm symptoms, are commonly used in clinical practice in patients with a suspected cervical radiculopathy. Their diagnostic accuracy, however, has never been examined in a systematic review. A comprehensive search was conducted in order to identify all possible studies fulfilling the inclusion criteria. A study was included if: (1) any provocative test of the neck for diagnosing cervical radiculopathy was identified; (2) any reference standard was used; (3) sensitivity and specificity were reported or could be (re-)calculated; and, (4) the publication was a full report. Two reviewers independently selected studies, and assessed methodological quality. Only six studies met the inclusion criteria, which evaluated five provocative tests. In general, Spurling’s test demonstrated low to moderate sensitivity and high specificity, as did traction/neck distraction, and Valsalva’s maneuver. The upper limb tension test (ULTT) demonstrated high sensitivity and low specificity, while the shoulder abduction test demonstrated low to moderate sensitivity and moderate to high specificity. Common methodological flaws included lack of an optimal reference standard, disease progression bias, spectrum bias, and review bias. Limitations include few primary studies, substantial heterogeneity, and numerous methodological flaws among the studies; therefore, a meta-analysis was not conducted. This review suggests that, when consistent with the history and other physical findings, a positive Spurling’s, traction/neck distraction, and Valsalva’s might be indicative of a cervical radiculopathy, while a negative ULTT might be used to rule it out. However, the lack of evidence precludes any firm conclusions regarding their diagnostic value, especially when used in primary care. More high quality studies are necessary in order to resolve this issue. PMID:17013656

  5. The robustness of diagnostic tests for GH deficiency in adults

    DEFF Research Database (Denmark)

    Andersen, Marianne

    2015-01-01

    , including conventional substitution therapy, influences the GH-responses. Recently, the role of IGF-I measurements in the clinical decision making has been discussed. The aim of this review is to discuss the available GH-stimulation tests. In this author's opinion, tests which include growth-hormone......Since the 1970s, GH treatment has been an important tool in paediatric endocrinology for the management of growth retardation. It is now accepted that adults with severe GH deficiency (GHD) demonstrate impaired physical and psychological well-being and may benefit from replacement therapy...... with recombinant human GH. There is, however, an ongoing debate on how to diagnose GHD, especially in adults. A GH response below the cut-off limit of a GH-stimulation test is required in most cases for establishing GHD in adults. No 'gold standard' GH-stimulation test exists, but some GH stimulation tests may...

  6. Diagnostic sensitivity of radiography, ultrasonography, and magnetic resonance imaging for detecting shoulder osteochondrosis/osteochondritis dissecans in dogs.

    Science.gov (United States)

    Wall, Corey R; Cook, Cristi R; Cook, James L

    2015-01-01

    Radiography, magnetic resonance imaging (MRI), and ultrasonography are commonly used for diagnosis of shoulder osteochondrosis and osteochondritis dissecans (OC/OCD) in dogs, however there is a lack of published information on the relative diagnostic sensitivities of these modalities. The purpose of this prospective study was to compare diagnostic sensitivities of these modalities for detecting shoulder OC/OCD in a group of dogs, using arthroscopy as the reference standard. Inclusion criteria were history and clinical findings consistent with osteochondrosis and/or osteochondritis dissecans involving at least one shoulder. With informed client consent, both shoulders for all included dogs were examined using standardized radiography, ultrasonography, MRI, and arthroscopy protocols. One of three veterinary surgeons recorded clinical and arthroscopic findings without knowledge of diagnostic imaging findings. One of two veterinary radiologists recorded diagnostic imaging findings without knowledge of clinical and arthroscopic findings. Eighteen client-owned dogs (n = 36 shoulders) met inclusion criteria. Diagnostic sensitivity, specificity, and accuracy (correct classification rate) values for detecting presence or absence of shoulder osteochondrosis/osteochondritis dissecans were as follows: radiography (88.5%, 90%, 88.9%), ultrasonography (92%, 60%, 82.6%), and MRI (96%, 88.9%, 94.4%). Odds of a correct diagnosis for MRI were 3.2 times more than ultrasonography and two times more than radiography. For MRI detection of lesions, the sagittal T2 or PD-FAT SAT sequences were considered to be most helpful. For radiographic detection of lesions, the additional supinated-mediolateral and pronated-mediolateral projections were considered to be most helpful. Findings from the current study support more evidence-based diagnostic imaging recommendations for dogs with clinically suspected shoulder osteochondrosis or osteochondritis dissecans. © 2014 American College of

  7. Diagnostic sensitivity of ultrasound, radiography and computed tomography for gender determination in four species of lizards.

    Science.gov (United States)

    Di Ianni, Francesco; Volta, Antonella; Pelizzone, Igor; Manfredi, Sabrina; Gnudi, Giacomo; Parmigiani, Enrico

    2015-01-01

    Gender determination is frequently requested by reptile breeders, especially for species with poor or absent sexual dimorphism. The aims of the current study were to describe techniques and diagnostic sensitivities of ultrasound, radiography, and computed tomography for gender determination (identification of hemipenes) in four species of lizards. Nineteen lizards of known sex, belonging to four different species (Pogona vitticeps, Uromastyx aegyptia, Tiliqua scincoides, Gerrhosaurus major) were prospectively enrolled. With informed owner consent, ultrasound, noncontrast CT, contrast radiography, and contrast CT (with contrast medium administered into the cloaca) were performed in conscious animals. Imaging studies were reviewed by three different operators, each unaware of the gender of the animals and of the results of the other techniques. The lizard was classified as a male when hemipenes were identified. Nineteen lizards were included in the study, 10 females and nine males. The hemipenes were seen on ultrasound in only two male lizards, and appeared as oval hypoechoic structures. Radiographically, hemipenes filled with contrast medium appeared as spindle-shaped opacities. Noncontrast CT identified hemipenes in only two lizards, and these appeared as spindle-shaped kinked structures with hyperattenuating content consistent with smegma. Hemipenes were correctly identified in all nine males using contrast CT (accuracy of 100%). Accuracy of contrast radiography was excellent (94.7%). Accuracy of ultrasound and of noncontrast CT was poor (64.3% and 63.1%, respectively). Findings from the current study supported the use of contrast CT or contrast radiography for gender determination in lizards. © 2014 American College of Veterinary Radiology.

  8. Connectivity diagnostics in the Mediterranean obtained from Lagrangian Flow Networks; global patterns, sensitivity and robustness

    Science.gov (United States)

    Monroy, Pedro; Rossi, Vincent; Ser-Giacomi, Enrico; López, Cristóbal; Hernández-García, Emilio

    2017-04-01

    Lagrangian Flow Network (LFN) is a modeling framework in which geographical sub-areas of the ocean are represented as nodes in a network and are interconnected by links representing the transport of water, substances or propagules (eggs and larvae) by currents. Here we compute for the surface of the whole Mediterranean basin four connectivity metrics derived from LFN that measure retention and exchange processes, thus providing a systematic characterization of propagule dispersal driven by the ocean circulation. Then we assess the sensitivity and robustness of the results with respect to the most relevant parameters: the density of released particles, the node size (spatial-scales of discretization), the Pelagic Larval Duration (PLD) and the modality of spawning. We find a threshold for the number of particles per node that guarantees reliable values for most of the metrics examined, independently of node size. For our setup, this threshold is 100 particles per node. We also find that the size of network nodes has a non-trivial influence on the spatial variability of both exchange and retention metrics. Although the spatio-temporal fluctuations of the circulation affect larval transport in a complex and unpredictable manner, our analyses evidence how specific biological parametrization impact the robustness of connectivity diagnostics. Connectivity estimates for long PLDs are more robust against biological uncertainties (PLD and spawning date) than for short PLDs. Furthermore, our model suggests that for mass-spawners that release propagules over short periods (≃ 2 to 10 days), daily release must be simulated to properly consider connectivity fluctuations. In contrast, average connectivity estimates for species that spawn repeatedly over longer duration (a few weeks to a few months) remain robust even using longer periodicity (5 to 10 days). Our results give a global view of the surface connectivity of the Mediterranean Sea and have implications for the design of

  9. Diagnostic utility of a direct immunofluorescence test to detect feline coronavirus antigen in macrophages in effusive feline infectious peritonitis.

    Science.gov (United States)

    Litster, A L; Pogranichniy, R; Lin, T-L

    2013-11-01

    The antemortem diagnosis of feline infectious peritonitis (FIP) remains challenging in clinical practice, since current testing methods have suboptimal diagnostic accuracy. Immunohistochemical testing of biopsy specimens and postmortem examination are the standard diagnostic methods, although direct immunofluorescence (DIF) testing to detect feline coronavirus in macrophages in effusion specimens has been reported to have 100% specificity and has been recommended as an antemortem confirmatory test. The aim of this study was to compare the results of DIF testing in antemortem feline effusions with postmortem results using field samples. Effusion specimens were collected antemortem from 17 cats and tested by DIF, followed by postmortem examination. Histopathological examination of specimens collected at postmortem confirmed FIP in 10/17 cases and ruled out FIP out in 7/17 cases. Antemortem DIF testing was positive in all 10 cases confirmed as FIP at postmortem examination. In the seven cats where FIP was ruled out at postmortem examination, DIF was negative in five cases and positive in the remaining two cases. The calculated sensitivity of DIF testing was 100% and the specificity was 71.4%. Duplicate effusion specimens from eight cats that were initially DIF positive were stored refrigerated (4 °C) or at room temperature (22-25 °C) and subjected to serial DIF testing to determine the duration of positive results. DIF-positive specimens stored at both temperatures retained their positive status for at least 2 days. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. A Novel Field-Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis

    Science.gov (United States)

    2016-10-01

    AWARD NUMBER: W81XWH-14-2-0195. Log Number: PR130282 TITLE: A Novel Field-Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis ...SUBTITLE A Novel Field-Deployable Point-of-Care Diagnostic Test for Cutaneous Leishmaniasis 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...14. ABSTRACT Leishmaniasis is caused by the protozoan Leishmania and is generally transmitted by the bite of sand flies of the genus Lutzomyia or

  11. Diagnosing ADHD in Adults: An Examination of the Discriminative Validity of Neuropsychological Tests and Diagnostic Assessment Instruments.

    Science.gov (United States)

    Pettersson, Richard; Söderström, Staffan; Nilsson, Kent W

    2015-12-17

    The objective of this study is to investigate the discriminative validity of neuropsychological tests and diagnostic assessment instruments in diagnosing adult ADHD in a clinical psychiatric population. Of 108 patients, 60 were diagnosed with ADHD. The Diagnostic Interview for ADHD in adults (DIVA 2.0) and Adult ADHD Self-Report Scale (ASRS) v.1.1 together with eight neuropsychological tests were investigated. All instruments showed poor discriminative ability except for the DIVA, which showed a relatively good ability to discriminate between the groups (sensitivity = 90.0; specificity = 72.9). A logistic regression analysis model with the DIVA and measures of inattention, impulsivity, and activity from continuous performance tests (CPTs) showed a sensitivity of 90.0 and a specificity of 83.3. Neuropsychological tests have a poor ability to discriminate between patients diagnosed with ADHD and patients not diagnosed with ADHD, but variables from CPT tests can contribute to increasing the specificity by 10% if used in combination with the DIVA. © The Author(s) 2015.

  12. Fecal microbiome analysis as a diagnostic test for diverticulitis.

    Science.gov (United States)

    Daniels, L; Budding, A E; de Korte, N; Eck, A; Bogaards, J A; Stockmann, H B; Consten, E C; Savelkoul, P H; Boermeester, M A

    2014-11-01

    Disease-specific variations in intestinal microbiome composition have been found for a number of intestinal disorders, but little is known about diverticulitis. The purpose of this study was to compare the fecal microbiota of diverticulitis patients with control subjects from a general gastroenterological practice and to investigate the feasibility of predictive diagnostics based on complex microbiota data. Thirty-one patients with computed tomography (CT)-proven left-sided uncomplicated acute diverticulitis were included and compared with 25 control subjects evaluated for a range of gastrointestinal indications. A high-throughput polymerase chain reaction (PCR)-based profiling technique (IS-pro) was performed on DNA isolates from baseline fecal samples. Differences in bacterial phylum abundance and diversity (Shannon index) of the resulting profiles were assessed by conventional statistics. Dissimilarity in microbiome composition was analyzed with principal coordinate analysis (PCoA) based on cosine distance measures. To develop a prediction model for the diagnosis of diverticulitis, we used cross-validated partial least squares discriminant analysis (PLS-DA). Firmicutes/Bacteroidetes ratios and Proteobacteria load were comparable among patients and controls (p = 0.20). The Shannon index indicated a higher diversity in diverticulitis for Proteobacteria (p Diverticulitis patients have a higher diversity of fecal microbiota than controls from a mixed population, with the phylum Proteobacteria defining the difference. The analysis of intestinal microbiota offers a novel way to diagnose diverticulitis.

  13. Endoscopy in GERD: Boondoggle, Diagnostic Test, or Risk Management Tool?

    Science.gov (United States)

    Vakil, Nimish

    2008-02-01

    The role of endoscopy in reflux disease is debated. Diagnostic certainty is attractive to patients and physicians, to affirm health and to ensure the absence of serious disease, but it is expensive and the majority of patients will have no endoscopic abnormalities. Empirical treatment with acid suppression in patients with symptoms of gastroesophageal reflux disease (GERD) is now widely practiced in primary care in many countries but in others, endoscopy is mandatory to receive approval from the payors for proton pump inhibitor therapy. In patients with dysphagia, endoscopy has a role in ruling out an obstructing lesion. A "once-in-a-lifetime" endoscopy has been proposed as a way to improve our ability to diagnose Barrett's esophagus, but cost-models suggest that this strategy is not cost-effective if current surveillance guidelines are followed after the diagnosis of Barrett's esophagus is made. The role of routine endoscopic examination in GERD is therefore questionable and needs better definition in carefully designed trials.

  14. Evaluation of the diagnostic accuracy of CareStart G6PD deficiency Rapid Diagnostic Test (RDT) in a malaria endemic area in Ghana, Africa.

    Science.gov (United States)

    Adu-Gyasi, Dennis; Asante, Kwaku Poku; Newton, Sam; Dosoo, David; Amoako, Sabastina; Adjei, George; Amoako, Nicholas; Ankrah, Love; Tchum, Samuel Kofi; Mahama, Emmanuel; Agyemang, Veronica; Kayan, Kingsley; Owusu-Agyei, Seth

    2015-01-01

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most widespread enzyme defect that can result in red cell breakdown under oxidative stress when exposed to certain medicines including antimalarials. We evaluated the diagnostic accuracy of CareStart G6PD deficiency Rapid Diagnostic Test (RDT) as a point-of-care tool for screening G6PD deficiency. A cross-sectional study was conducted among 206 randomly selected and consented participants from a group with known G6PD deficiency status between February 2013 and June 2013. A maximum of 1.6ml of capillary blood samples were used for G6PD deficiency screening using CareStart G6PD RDT and Trinity qualitative with Trinity quantitative methods as the "gold standard". Samples were also screened for the presence of malaria parasites. Data entry and analysis were done using Microsoft Access 2010 and Stata Software version 12. Kintampo Health Research Centre Institutional Ethics Committee granted ethical approval. The sensitivity (SE) and specificity (SP) of CareStart G6PD deficiency RDT was 100% and 72.1% compared to Trinity quantitative method respectively and was 98.9% and 96.2% compared to Trinity qualitative method. Malaria infection status had no significant (P=0.199) change on the performance of the G6PD RDT test kit compared to the "gold standard". The outcome of this study suggests that the diagnostic performance of the CareStart G6PD deficiency RDT kit was high and it is acceptable at determining the G6PD deficiency status in a high malaria endemic area in Ghana. The RDT kit presents as an attractive tool for point-of-care G6PD deficiency for rapid testing in areas with high temperatures and less expertise. The CareStart G6PD deficiency RDT kit could be used to screen malaria patients before administration of the fixed dose primaquine with artemisinin-based combination therapy.

  15. Novel Diagnostic Tests to Detect Helicobacter pylori Infection: A Pediatric Perspective

    Directory of Open Access Journals (Sweden)

    John D Snyder

    1999-01-01

    Full Text Available Because of the widespread problem of Helicobacter pylori infections, there is an increased need for rapid, reliable and inexpensive diagnostic tests. Five recently developed tests that offer potential advantages because they are less invasive or permit easier acquisition of samples than available tests are assessed. The tests assessed are whole blood, saliva and urine assays that measure systemic antibody response to H pylori, stool tests that measure H pylori antigens and string tests that recover H pylori organisms.

  16. Development of a Diagnostic Blood Test for Breast Cancer

    National Research Council Canada - National Science Library

    Gabrielson, Edward

    2002-01-01

    .... During the second year of this study, a small number of serum samples from breast cancer patients were tested for methylation of genes previously determined to be methylated in the cancer tissue...

  17. Diagnostic accuracy of a two-item Drug Abuse Screening Test (DAST-2).

    Science.gov (United States)

    Tiet, Quyen Q; Leyva, Yani E; Moos, Rudolf H; Smith, Brandy

    2017-11-01

    Drug use is prevalent and costly to society, but individuals with drug use disorders (DUDs) are under-diagnosed and under-treated, particularly in primary care (PC) settings. Drug screening instruments have been developed to identify patients with DUDs and facilitate treatment. The Drug Abuse Screening Test (DAST) is one of the most well-known drug screening instruments. However, similar to many such instruments, it is too long for routine use in busy PC settings. This study developed and validated a briefer and more practical DAST for busy PC settings. We recruited 1300 PC patients in two Department of Veterans Affairs (VA) clinics. Participants responded to a structured diagnostic interview. We randomly selected half of the sample to develop and the other half to validate the new instrument. We employed signal detection techniques to select the best DAST items to identify DUDs (based on the MINI) and negative consequences of drug use (measured by the Inventory of Drug Use Consequences). Performance indicators were calculated. The two-item DAST (DAST-2) was 97% sensitive and 91% specific for DUDs in the development sample and 95% sensitive and 89% specific in the validation sample. It was highly sensitive and specific for DUD and negative consequences of drug use in subgroups of patients, including gender, age, race/ethnicity, marital status, educational level, and posttraumatic stress disorder status. The DAST-2 is an appropriate drug screening instrument for routine use in PC settings in the VA and may be applicable in broader range of PC clinics. Published by Elsevier Ltd.

  18. Accuracy of diagnostic antibody tests for coeliac disease in children

    DEFF Research Database (Denmark)

    Giersiepen, Klaus; Lelgemann, Monika; Stuhldreher, Nina

    2012-01-01

    The aim of this study was to summarise the evidence from 2004 to September 2009 on the performance of laboratory-based serological and point of care (POC) tests for diagnosing coeliac disease (CD) in children using histology as reference standard.......The aim of this study was to summarise the evidence from 2004 to September 2009 on the performance of laboratory-based serological and point of care (POC) tests for diagnosing coeliac disease (CD) in children using histology as reference standard....

  19. FMIT test cell diagnostics: a unique materials challenge

    International Nuclear Information System (INIS)

    Cannon, C.P.; Fuller, J.L.

    1981-08-01

    Basic materials problems are discussed in instrumenting the FMIT test cell, which are applicable to fusion devices in general. Recent data on ceramic-to-metal seals, mineral insulated instrument cables, thermocouples, and optical components are reviewed. The data makes it clear that it would be a mistake to assume that materials and instruments will behave in the FMIT test cell environment as they do in more familiar fission reactors and low power accelerators

  20. Decision-Making about Healthcare Related Tests and Diagnostic Strategies: User Testing of GRADE Evidence Tables.

    Directory of Open Access Journals (Sweden)

    Reem A Mustafa

    Full Text Available To develop guidance on what information to include and how to present it in tables summarizing the evidence from systematic reviews of test accuracy following the Grading of Recommendations Assessment, Development and Evaluation (GRADE approach.To design and refine the evidence tables, we used an iterative process based on the analysis of data from four rounds of discussions, feedback and user testing. During the final round, we conducted one-on-one user testing with target end users. We presented a number of alternative formats of evidence tables to participants and obtained information about users' understanding and preferences.More than 150 users participated in initial discussions and provided their formal and informal feedback. 20 users completed one-on-one user testing interviews. Almost all participants preferred summarizing the results of systematic reviews of test accuracy in tabular format rather than plain text. Users generally preferred less complex tables but found presenting sensitivity and specificity estimates only as too simplistic. Users found the presentation of test accuracy for several values of prevalence initially confusing but modifying table layout and adding sample clinical scenarios for each prevalence reduced this confusion. Providing information about clinical consequences of testing result was viewed as not feasible for authors of systematic reviews.We present the current formats for tables presenting test accuracy following the GRADE approach. These tables can be developed using GRADEpro guidelines development tool (www.guidelinedevelopment.org or www.gradepro.org and are being further developed into electronic interactive tables that will suit the needs of different end users. The formatting of these tables, and how they influence result interpretation and decision-making will be further evaluated in a randomized trial.

  1. Mycobacteria: laboratory methods for testing drug sensitivity and resistance

    Science.gov (United States)

    Canetti, G.; Froman, S.; Grosset, J.; Hauduroy, P.; Langerová, Miloslava; Mahler, H. T.; Meissner, Gertrud; Mitchison, D. A.; Šula, L.

    1963-01-01

    In its seventh report, published in 1960, the WHO Expert Committee on Tuberculosis “noted the need for international standards for the definition and determination of drug resistance which will permit comparisons to be made from one area to another, and recommended that the World Health Organization take appropriate steps to establish such standards”.10 Acting on this recommendation, WHO took the first step towards standardization by convening in Geneva, in December 1961, an informal international meeting of specialists in the bacteriology of tuberculosis. At this meeting an attempt was made to formulate prerequisites for reliable sensitivity tests and to specify the technical procedures for them. The first part of the present paper is a joint contribution by the participants in the meeting, summarizing the general conclusions reached and recommendations made with regard to tests of sensitivity to the three main antituberculosis drugs—isoniazid, streptomycin and p-aminosalicylic acid. The other three parts describe, in turn, three different tests for determining drug sensitivity—the absolute-concentration method, the resistance-ratio method and the proportion method—that are generally considered to give reasonably accurate results. PMID:14102034

  2. Diagnostic performance and costs of contingent screening models for trisomy 21 incorporating non-invasive prenatal testing.

    Science.gov (United States)

    Maxwell, Susannah; O'Leary, Peter; Dickinson, Jan E; Suthers, Graeme K

    2017-08-01

    Contingent screening for trisomy 21 using non-invasive prenatal testing has the potential to reduce invasive diagnostic testing and increase the detection of trisomy 21. To describe the diagnostic and economic performance of prenatal screening models for trisomy 21 that use non-invasive prenatal testing as a contingent screen across a range of combined first trimester screening risk cut-offs from a public health system perspective. Using a hypothetical cohort of 300 000 pregnancies, we modelled the outcomes of 25 contingent non-invasive prenatal testing screening models and compared these to conventional screening, offering women with a high-risk (1 > 300) combined first trimester screening result an invasive test. The 25 models used a range of risk cut-offs. High-risk women were offered invasive testing. Intermediate-risk women were offered non-invasive prenatal testing. We report the cost of each model, detection rate, costs per diagnosis, invasive tests per diagnosis and the number of fetal losses per diagnosis. The cost per prenatal diagnosis of trisomy 21 using the conventional model was $51 876 compared to the contingent models which varied from $49 309-66 686. The number of diagnoses and cost per diagnosis increased as the intermediate-risk threshold was lowered. Results were sensitive to trisomy 21 incidence, uptake of testing and cost of non-invasive prenatal testing. Contingent non-invasive prenatal testing models using more sensitive combined first trimester screening risk cut-offs than conventional screening improved the detection rate of trisomy 21, reduced procedure-related fetal loss and could potentially be provided at a lower cost per diagnosis than conventional screening. © 2017 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  3. Collection and Characterization of Samples for Establishment of a Serum Repository for Lyme Disease Diagnostic Test Development and Evaluation

    Science.gov (United States)

    Molins, Claudia R.; Sexton, Christopher; Young, John W.; Ashton, Laura V.; Pappert, Ryan; Beard, Charles B.

    2014-01-01

    Serological assays and a two-tiered test algorithm are recommended for laboratory confirmation of Lyme disease. In the United States, the sensitivity of two-tiered testing using commercially available serology-based assays is dependent on the stage of infection and ranges from 30% in the early localized disease stage to near 100% in late-stage disease. Other variables, including subjectivity in reading Western blots, compliance with two-tiered recommendations, use of different first- and second-tier test combinations, and use of different test samples, all contribute to variation in two-tiered test performance. The availability and use of sample sets from well-characterized Lyme disease patients and controls are needed to better assess the performance of existing tests and for development of improved assays. To address this need, the Centers for Disease Control and Prevention and the National Institutes of Health prospectively collected sera from patients at all stages of Lyme disease, as well as healthy donors and patients with look-alike diseases. Patients and healthy controls were recruited using strict inclusion and exclusion criteria. Samples from all included patients were retrospectively characterized by two-tiered testing. The results from two-tiered testing corroborated the need for novel and improved diagnostics, particularly for laboratory diagnosis of earlier stages of infection. Furthermore, the two-tiered results provide a baseline with samples from well-characterized patients that can be used in comparing the sensitivity and specificity of novel diagnostics. Panels of sera and accompanying clinical and laboratory testing results are now available to Lyme disease serological test users and researchers developing novel tests. PMID:25122862

  4. A novel bedside diagnostic test for methanol poisoning using dry chemistry for formate.

    Science.gov (United States)

    Hovda, Knut Erik; Gadeholt, Gaut; Evtodienko, Vladimir; Jacobsen, Dag

    2015-11-01

    The standard diagnostic approach to methanol poisoning is chromatographic measurement of methanol on centrally placed stationary equipment. Methanol poisoning in places where such equipment is unavailable is thus often not diagnosed. Methanol is metabolized to a toxic metabolite, formate; the presence of this compound indicates methanol poisoning. We have developed an enzymatic test for formate and modified it into a portable dry chemistry system that could be used anywhere. The method consists of two enzymatic steps: Formation of NADH from NAD by formate dehydrogenase, and subsequent use of NADH as a reductant of a tetrazolium into a formazan dye that can be quantified photometrically or visually. The photometer gave a good correlation of R(2) = 0.9893 in serum and R(2) = 0.9949 in whole blood, showing an instrumental detection limit of less than 1 mM (4.5 mg/dL). The visual readings showed a correlation of R(2) = 0.8966. Users experienced some difficulty in separating the negative control from the low positives. We have documented the feasibility of an affordable formate strip test for bedside diagnosis of methanol poisoning and for screening of metabolic acidosis of unknown origin. Visual reading is possible, but a reader will improve reliability at lower levels of formate. Future studies are necessary to study the sensitivity and specificity towards other causes of metabolic acidosis and other acids present in human blood.

  5. Rapid diagnostic tests duo as alternative to conventional serological assays for conclusive Chagas disease diagnosis.

    Directory of Open Access Journals (Sweden)

    Karina E Egüez

    2017-04-01

    Full Text Available Chagas disease is caused by the parasite Trypanosoma cruzi. It affects several million people, mainly in Latin America, and severe cardiac and/or digestive complications occur in ~30% of the chronically infected patients. Disease acute stage is mostly asymptomatic and infection goes undiagnosed. In the chronic phase direct parasite detection is hampered due to its concealed presence and diagnosis is achieved by serological methods, like ELISA or indirect hemagglutination assays. Agreement in at least two tests must be obtained due to parasite wide antigenic variability. These techniques require equipped labs and trained personnel and are not available in distant regions. As a result, many infected people often remain undiagnosed until it is too late, as the two available chemotherapies show diminished efficacy in the advanced chronic stage. Easy-to-use rapid diagnostic tests have been developed to be implemented in remote areas as an alternative to conventional tests. They do not need electricity, nor cold chain, they can return results within an hour and some even work with whole blood as sample, like Chagas Stat-Pak (ChemBio Inc. and Chagas Detect Plus (InBIOS Inc.. Nonetheless, in order to qualify a rapidly diagnosed positive patient for treatment, conventional serological confirmation is obligatory, which might risk its start. In this study two rapid tests based on distinct antigen sets were used in parallel as a way to obtain a fast and conclusive Chagas disease diagnosis using whole blood samples. Chagas Stat-Pak and Chagas Detect Plus were validated by comparison with three conventional tests yielding 100% sensitivity and 99.3% specificity over 342 patients seeking Chagas disease diagnosis in a reference centre in Sucre (Bolivia. Combined used of RDTs in distant regions could substitute laborious conventional serology, allowing immediate treatment and favouring better adhesion to it.

  6. Rapid diagnostic tests duo as alternative to conventional serological assays for conclusive Chagas disease diagnosis

    Science.gov (United States)

    Egüez, Karina E.; Terán, Carolina; Chipana, Zenobia; García, Wilson; Torrico, Faustino; Gascon, Joaquim; Lozano-Beltran, Daniel-Franz; Pinazo, María-Jesús

    2017-01-01

    Chagas disease is caused by the parasite Trypanosoma cruzi. It affects several million people, mainly in Latin America, and severe cardiac and/or digestive complications occur in ~30% of the chronically infected patients. Disease acute stage is mostly asymptomatic and infection goes undiagnosed. In the chronic phase direct parasite detection is hampered due to its concealed presence and diagnosis is achieved by serological methods, like ELISA or indirect hemagglutination assays. Agreement in at least two tests must be obtained due to parasite wide antigenic variability. These techniques require equipped labs and trained personnel and are not available in distant regions. As a result, many infected people often remain undiagnosed until it is too late, as the two available chemotherapies show diminished efficacy in the advanced chronic stage. Easy-to-use rapid diagnostic tests have been developed to be implemented in remote areas as an alternative to conventional tests. They do not need electricity, nor cold chain, they can return results within an hour and some even work with whole blood as sample, like Chagas Stat-Pak (ChemBio Inc.) and Chagas Detect Plus (InBIOS Inc.). Nonetheless, in order to qualify a rapidly diagnosed positive patient for treatment, conventional serological confirmation is obligatory, which might risk its start. In this study two rapid tests based on distinct antigen sets were used in parallel as a way to obtain a fast and conclusive Chagas disease diagnosis using whole blood samples. Chagas Stat-Pak and Chagas Detect Plus were validated by comparison with three conventional tests yielding 100% sensitivity and 99.3% specificity over 342 patients seeking Chagas disease diagnosis in a reference centre in Sucre (Bolivia). Combined used of RDTs in distant regions could substitute laborious conventional serology, allowing immediate treatment and favouring better adhesion to it. PMID:28369081

  7. Rapid diagnostic tests duo as alternative to conventional serological assays for conclusive Chagas disease diagnosis.

    Science.gov (United States)

    Egüez, Karina E; Alonso-Padilla, Julio; Terán, Carolina; Chipana, Zenobia; García, Wilson; Torrico, Faustino; Gascon, Joaquim; Lozano-Beltran, Daniel-Franz; Pinazo, María-Jesús

    2017-04-01

    Chagas disease is caused by the parasite Trypanosoma cruzi. It affects several million people, mainly in Latin America, and severe cardiac and/or digestive complications occur in ~30% of the chronically infected patients. Disease acute stage is mostly asymptomatic and infection goes undiagnosed. In the chronic phase direct parasite detection is hampered due to its concealed presence and diagnosis is achieved by serological methods, like ELISA or indirect hemagglutination assays. Agreement in at least two tests must be obtained due to parasite wide antigenic variability. These techniques require equipped labs and trained personnel and are not available in distant regions. As a result, many infected people often remain undiagnosed until it is too late, as the two available chemotherapies show diminished efficacy in the advanced chronic stage. Easy-to-use rapid diagnostic tests have been developed to be implemented in remote areas as an alternative to conventional tests. They do not need electricity, nor cold chain, they can return results within an hour and some even work with whole blood as sample, like Chagas Stat-Pak (ChemBio Inc.) and Chagas Detect Plus (InBIOS Inc.). Nonetheless, in order to qualify a rapidly diagnosed positive patient for treatment, conventional serological confirmation is obligatory, which might risk its start. In this study two rapid tests based on distinct antigen sets were used in parallel as a way to obtain a fast and conclusive Chagas disease diagnosis using whole blood samples. Chagas Stat-Pak and Chagas Detect Plus were validated by comparison with three conventional tests yielding 100% sensitivity and 99.3% specificity over 342 patients seeking Chagas disease diagnosis in a reference centre in Sucre (Bolivia). Combined used of RDTs in distant regions could substitute laborious conventional serology, allowing immediate treatment and favouring better adhesion to it.

  8. 42 CFR 414.506 - Procedures for public consultation for payment for a new clinical diagnostic laboratory test.

    Science.gov (United States)

    2010-10-01

    ... a new clinical diagnostic laboratory test. 414.506 Section 414.506 Public Health CENTERS FOR... FOR PART B MEDICAL AND OTHER HEALTH SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.506 Procedures for public consultation for payment for a new clinical diagnostic laboratory test...

  9. Consequences of different diagnostic "gold standards" in test accuracy research: Carpal Tunnel Syndrome as an example.

    Science.gov (United States)

    Bachmann, Lucas M; Jüni, Peter; Reichenbach, Stephan; Ziswiler, Hans-Rudolf; Kessels, Alfons G; Vögelin, Esther

    2005-08-01

    Test accuracy studies assume the existence of a well-defined illness definition and clear-cut diagnostic gold standards or reference standards. However, in clinical reality illness definitions may be vague or a mere description of a set of manifestations, mostly clinical signs and symptoms. This can lead to disagreements among experts about the correct classification of an illness and the adequate reference standard. Using data from a diagnostic accuracy study in carpal tunnel syndrome, we explored the impact of different definitions on the estimated test accuracy and found that estimated test performance characteristics varied considerably depending on the chosen reference standard. In situations without a clear-cut illness definition, randomized controlled trials may be preferable to test accuracy studies for the evaluation of a novel test. These studies do not determine the diagnostic accuracy, but the clinical impact of a novel test on patient management and outcome.

  10. [Critical reading of articles about diagnostic tests (part I): Are the results of the study valid?].

    Science.gov (United States)

    Arana, E

    2015-01-01

    In the era of evidence-based medicine, one of the most important skills a radiologist should have is the ability to analyze the diagnostic literature critically. This tutorial aims to present guidelines for determining whether primary diagnostic articles are valid for clinical practice. The following elements should be evaluated: whether the study can be applied to clinical practice, whether the technique was compared to the reference test, whether an appropriate spectrum of patients was included, whether expectation bias and verification bias were limited, the reproducibility of the study, the practical consequences of the study, the confidence intervals for the parameters analyzed, the normal range for continuous variables, and the placement of the test in the context of other diagnostic tests. We use elementary practical examples to illustrate how to select and interpret the literature on diagnostic imaging and specific references to provide more details. Copyright © 2014 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

  11. Evaluation of the Becton Dickinson Rapid Influenza Diagnostic Tests in Outpatients in Germany during Seven Influenza Seasons.

    Directory of Open Access Journals (Sweden)

    Maren Eggers

    Full Text Available An extensive retrospective study spanning several seasons was undertaken to evaluate the diagnostic performance of the BD rapid influenza diagnostic test (RIDT in comparison with the RT-PCR assay.A total of 2,179 respiratory samples were tested in parallel by in-house RT-PCR and the RIDT. During the 2003-2004, 2006-2007, 2007-2008, and 2008-2009 (n=1671 seasons, the BD Directigen Flu A+B test was used, and during the 2010-2011, 2011-2012 and 2012-2013 (n=508 seasons, the BD Directigen EZ Flu A+B test b was used.The sensitivity, specificity, PPV and NPV for the BD Directigen Flu A+B test calculated for types A and B together were 39%, 99%, 98%, and 56%, respectively. For the BD Directigen EZ Flu A+B test, these values were 47%, 100%, 100%, 55%, respectively. The sensitivity of the BD Directigen Flu A+B test did not differ significantly from season to season or between types A (44% and B (37%. The sensitivity of the BD Directigen EZ Flu A+B test calculated for type A only was 59%, which was considerably higher than the sensitivity of this test for type B (23%. The sensitivity of the RIDT was approximately 40-50% in children and teenagers, but it was only 18.% in adults aged 20 years and older. The specificity of both RIDTs was very high (>99% during all seasons.Due to their rapid turnaround time, RIDTs can help guide decisions about the clinical management of influenza. Because of the high specificity, a positive result can be interpreted as a true positive, and antiviral therapy as well as appropriate measures to prevent the transmission of influenza can be initiated. The best sensitivity of the RIDT is achieved in children. However, even in this group, the RIDT will only recognize influenza infection in approximately half of the cases, and influenza should still be considered in patients with negative results; negative RIDT results must be confirmed by PCR.

  12. Auditory Automotive Mechanics Diagnostic Achievement Test. Center Technical Paper No. 2.

    Science.gov (United States)

    Swanson, Richard Arthur

    The Auditory Automotive Mechanics Diagnostic Achievement Test assesses an automobile mechanic's ability to determine mechanical faults from auditory cues alone. The 44-item test and its instructions are recorded on magnetic tape; answer choices are presented on tape, and are also written in the printed test booklets. The norming and validity…

  13. The furosemide diagnostic test in suspected slow-onset heart failure : popular but not useful

    NARCIS (Netherlands)

    Kelder, Johannes C.; Cramer, Maarten J.; Rutten, Frans H.; Plokker, H. W.; Grobbee, Diederick E.; Hoes, Arno W.

    Aims Early, slow-onset heart failure is difficult to diagnose from just signs and symptoms. The physician needs ancillary diagnostic tests. The 'loop-diuretic test' or 'furosemide test', characterized as weight loss and alleviation of symptoms after a short course of a loop-diuretic, could be a

  14. Cutback sensitivity test for boron-free small modular PWR

    Science.gov (United States)

    Choe, J.; Shin, H. C.; Jeong, J. E.; Lee, D.

    2016-08-01

    A soluble boron-free small modular pressurized water reactor (SMPWR) uses burnable absorbers (BA) instead of soluble boron to reduce excess reactivity. As a consequence, the fuel cycle length can be shortened by the residual penalty of BA. This paper performs cutback sensitivity tests to extend the cycle length. The influence of the height of the cutback, of the 235U enrichment rate, and of the BA material on the power peaking factor (Fq), the axial offset (AO) and the fuel cycle length is analyzed with the reactor core design system, CASMO-4E/SIMULATE-3 code system.

  15. A meta-analysis of the diagnostic accuracy of dengue virus-specific IgA antibody-based tests for detection of dengue infection.

    Science.gov (United States)

    Alagarasu, K; Walimbe, A M; Jadhav, S M; Deoshatwar, A R

    2016-03-01

    Immunoglobulin A (IgA)-based tests have been evaluated in different studies for their utility in diagnosing dengue infections. In most of the studies, the results were inconclusive because of a small sample size. Hence, a meta-analysis involving nine studies with 2096 samples was performed to assess the diagnostic accuracy of IgA-based tests in diagnosing dengue infections. The analysis was conducted using Meta-Disc software. The results revealed that IgA-based tests had an overall sensitivity, specificity, diagnostic odds ratio, and positive and negative likelihood ratios of 73·9%, 95·2%, 66·7, 22·0 and 0·25, respectively. Significant heterogeneity was observed between the studies. The type of test, infection status and day of sample collection influenced the diagnostic accuracy. The IgA-based diagnostic tests showed a greater accuracy when the samples were collected 4 days after onset of symptoms and for secondary infections. The results suggested that IgA-based tests had a moderate level of accuracy and are diagnostic of the disease. However, negative results cannot be used alone for dengue diagnosis. More prospective studies comparing the diagnostic accuracy of combinations of antigen-based tests with either IgA or IgM are needed and might be useful for suggesting the best strategy for dengue diagnosis.

  16. Feline focus: Diagnostic testing for feline thyroid disease: hypothyroidism.

    Science.gov (United States)

    Peterson, Mark E

    2013-08-01

    Although naturally occurring hypothyroidism is very rare in cats, iatrogenic hypothyroidism is a recognized complication of treatment for hyperthyroidism. However, confirming the diagnosis of hypothyroidism in cats is not generally straightforward. The potential for false-negative and false-positive results exists with all thyroid function tests, especially in older cats that may have concurrent nonthyroidal illness. Therefore, all thyroid function test results must be interpreted in light of the cat's history, clinical signs, and other laboratory findings. If a low to low-normal serum thyroxine (T4) value is found in a cat that has been treated for hyperthyroidism, repeating the total T4 analysis, determining free T4 and thyroid stimulating hormone (TSH) concentrations, or performing a TSH stimulation test or thyroid scintigraphy may be needed to confirm the diagnosis.

  17. Comparative evaluation of two rapid field tests for malaria diagnosis: Partec Rapid Malaria Test® and Binax Now® Malaria Rapid Diagnostic Test.

    Science.gov (United States)

    Nkrumah, Bernard; Acquah, Samuel Ek; Ibrahim, Lukeman; May, Juergen; Brattig, Norbert; Tannich, Egbert; Nguah, Samuel Blay; Adu-Sarkodie, Yaw; Huenger, Frank

    2011-05-23

    About 90% of all malaria deaths in sub-Saharan Africa occur in children under five years. Fast and reliable diagnosis of malaria requires confirmation of the presence of malaria parasites in the blood of patients with fever or history suggestive of malaria; hence a prompt and accurate diagnosis of malaria is the key to effective disease management. Confirmation of malaria infection requires the availability of a rapid, sensitive, and specific testing at an affordable cost. We compared two recent methods (the novel Partec Rapid Malaria Test® (PT) and the Binax Now® Malaria Rapid Diagnostic Test (BN RDT) with the conventional Giemsa stain microscopy (GM) for the diagnosis of malaria among children in a clinical laboratory of a hospital in a rural endemic area of Ghana. Blood samples were collected from 263 children admitted with fever or a history of fever to the pediatric clinic of the Agogo Presbyterian Hospital. The three different test methods PT, BN RDT and GM were performed independently by well trained and competent laboratory staff to assess the presence of malaria parasites. Results were analyzed and compared using GM as the reference standard. In 107 (40.7%) of 263 study participants, Plasmodium sp. was detected by GM. PT and BN RDT showed positive results in 111 (42.2%) and 114 (43.4%), respectively. Compared to GM reference standard, the sensitivities of the PT and BN RDT were 100% (95% CI: 96.6-100) and 97.2% (95% CI: 92.0-99.4), respectively, specificities were 97.4% (95% CI: 93.6-99.3) and 93.6% (95% CI: 88.5-96.9), respectively. There was a strong agreement (kappa) between the applied test methods (GM vs PT: 0.97; p < 0.001 and GM vs BN RDT: 0.90; p < 0.001). The average turnaround time per tests was 17 minutes. In this study two rapid malaria tests, PT and BN RDT, demonstrated a good quality of their performance compared to conventional GM. Both methods require little training, have short turnaround times, are applicable as well as affordable and

  18. Using a web-based application to define the accuracy of diagnostic tests when the gold standard is imperfect.

    Directory of Open Access Journals (Sweden)

    Cherry Lim

    Full Text Available Estimates of the sensitivity and specificity for new diagnostic tests based on evaluation against a known gold standard are imprecise when the accuracy of the gold standard is imperfect. Bayesian latent class models (LCMs can be helpful under these circumstances, but the necessary analysis requires expertise in computational programming. Here, we describe open-access web-based applications that allow non-experts to apply Bayesian LCMs to their own data sets via a user-friendly interface.Applications for Bayesian LCMs were constructed on a web server using R and WinBUGS programs. The models provided (http://mice.tropmedres.ac include two Bayesian LCMs: the two-tests in two-population model (Hui and Walter model and the three-tests in one-population model (Walter and Irwig model. Both models are available with simplified and advanced interfaces. In the former, all settings for Bayesian statistics are fixed as defaults. Users input their data set into a table provided on the webpage. Disease prevalence and accuracy of diagnostic tests are then estimated using the Bayesian LCM, and provided on the web page within a few minutes. With the advanced interfaces, experienced researchers can modify all settings in the models as needed. These settings include correlation among diagnostic test results and prior distributions for all unknown parameters. The web pages provide worked examples with both models using the original data sets presented by Hui and Walter in 1980, and by Walter and Irwig in 1988. We also illustrate the utility of the advanced interface using the Walter and Irwig model on a data set from a recent melioidosis study. The results obtained from the web-based applications were comparable to those published previously.The newly developed web-based applications are open-access and provide an important new resource for researchers worldwide to evaluate new diagnostic tests.

  19. Diagnostic accuracy of rapid urease test for the diagnosis of ...

    African Journals Online (AJOL)

    Background: The strong association of Helicobacter pylori (H. pylori) with dyspepsia has caused a major paradigm shift in patients' management. It has been observed that histology is usually employed as the routine test for the diagnosing H. pylori in centres where Oesophagogastroduodenoscopy (OGD) is available in ...

  20. Selected diagnostic ophthalmic tests in the red kangaroo (Macropus rufus).

    Science.gov (United States)

    Takle, Ginger L; Suedmeyer, W Kirk; Hunkeler, Amy

    2010-06-01

    The following tests were performed on a total of 20 eyes: Schirmer tear test, intraocular pressure (IOP), assessment of conjunctival flora, and pupillary diameter with application of topical tropicamide in 10 healthy captive red kangaroos (Macropus rufus) under manual restraint. The mean Schirmer tear test value was 22.6 +/- 6.07 mm/min. The mean intraocular pressure was 17.45 +/- 7.23 mm Hg. Values did not differ between eyes or gender for either test, but significant differences were identified for IOP values according to age. The most common bacteria isolated from the conjunctival fornix were Staphylococcus epidermidis (54.5%) and Corynebacterium sp. (18.2%). The mean onset of mydriasis after instillation of 1% tropicamide ophthalmic solution was 16.7 +/- 3.34 min and the mean duration of effect was 17.6 +/- 8.26 hr. The data obtained in this investigation will aid veterinary ophthalmologists and zoo veterinarians to diagnose ocular diseases in the red kangaroo accurately.

  1. Laboratory tests for malaria: A diagnostic conundrum? | Puri | South ...

    African Journals Online (AJOL)

    Objectives. To detect malarial parasites using the peripheral blood smear (PBS) and to compare the PBS with the immunochromatographic antigen test (i.e. OptiMAL and polymerase chain reaction (PCR)). Methods. Six ml of blood was collected from each of 170 patients clinically suspected of having malaria.

  2. A comparison of diagnostic tests for lactose malabsorption - which one is the best?

    Directory of Open Access Journals (Sweden)

    Hovde Øistein

    2009-10-01

    Full Text Available Abstract Background Perceived milk intolerance is a common complaint, and tests for lactose malabsorption (LM are unreliable. This study assesses the agreement between diagnostic tests for LM and describes the diagnostic properties of the tests. Methods Patients above 18 years of age with suspected LM were included. After oral intake of 25 g lactose, a combined test with measurement of serum glucose (s-glucose and hydrogen (H2 and methane (CH4 in expired air was performed and symptoms were recorded. In patients with discrepancies between the results, the combined test was repeated and a gene test for lactose non-persistence was added. The diagnosis of LM was based on an evaluation of all tests. The following tests were compared: Increase in H2, CH4, H2+CH4 and H2+CH4x2 in expired air, increase in s-glucose, and symptoms. The agreement was calculated and the diagnostic properties described. Results Sixty patients were included, seven (12% had LM. The agreement (kappa-values between the methods varied from 0.25 to 0.91. The best test was the lactose breath test with measurement of the increase in H2 + CH4x2 in expired air. With a cut-off level Conclusion The agreement between commonly used methods for the diagnosis of LM was unsatisfactory. A lactose breath test with measurement of H2 + CH4x2 in expired air had the best diagnostic properties.

  3. Clinical and Demographic Stratification of Test Performance: A Pooled Analysis of Five Laboratory Diagnostic Methods for American Cutaneous Leishmaniasis

    Science.gov (United States)

    Boggild, Andrea K.; Ramos, Ana P.; Espinosa, Diego; Valencia, Braulio M.; Veland, Nicolas; Miranda-Verastegui, Cesar; Arevalo, Jorge; Low, Donald E.; Llanos-Cuentas, Alejandro

    2010-01-01

    We evaluated performance characteristics of five diagnostic methods for cutaneous leishmaniasis. Patients who came to the Leishmania Clinic of Hospital Nacional Cayetano Heredia in Lima, Peru, were enrolled in the study. Lesion smears, culture, microculture, polymerase chain reaction (PCR), and leishmanin skin test (LST) were performed. A total of 145 patients with 202 lesions were enrolled: 114 patients with 161 lesions fulfilled criteria for cutaneous leishmaniasis. Sensitivity and specificity were 57.8% (95% confidence interval [CI] = 50.2–65.4%) and 100.0% for culture, 78.3% (95% CI = 71.9–84.7%) and 100.0% for microculture, 71.4% (95% CI = 64.4–78.4%) and 100.0% for smears, 78.2% (95% CI = 70.6–85.8%) and 77.4% (95% CI = 62.7–92.1%) for LST, and 96.9% (95% CI = 94.2–99.6%) and 65.9% (95% CI = 51.4–80.4%) for PCR. PCR was more sensitive than the other assays (P < 0.001). Sensitivities of culture, smears, and LST varied by lesion duration and appearance. PCR offers performance advantages over other assays, irrespective of patient age, sex, lesion duration, or appearance. That clinical factors influence performance of non-molecular assays offers clinicians a patient-focused approach to diagnostic test selection. PMID:20682880

  4. [The functional tests in clinical diagnostic laboratory: the detection of magnesium deficiency in the loading test].

    Science.gov (United States)

    Kondakov, A V; Kobylianskiĭ, A G; Tishchenkov, V G; Titov, V N

    2012-06-01

    The article deals with the value and role of functional tests in practice of clinical diagnostic laboratories. The possibilities of evaluation of biological function of homeostasis according the changes of magnesium ions or calcium concentration in urine or blood hence reflecting the deficiency of these ions in vivo. The magnesium tolerant test is described It is demonstrated that it can be applied both in curative preventive institutions and ambulatories. In the examined group of patients, 78% had physiologic parameters of magnesium concentration, 17% suffered from hypermagnesiumuria and 5%--from hypermagnesiumuria. The magnesium deficiency of different degree was detected in 87% of patients. In the most part of patients with magnesium deficiency normomagnesiumuria was detected. Only in one case with normomagnesiumuria the magnesium deficiency was absent. In 30% of patients with magnesium deficiency the concentration of cation in day urine decreased up to 2.2 times after load dose. In absence of deficiency the monotony of cation's excretion was noted. Under the magnesium deficiency the character of process changed but velocity of excretion of magnesium after load probe slightly decreased relative to values before the load. The impact of alcohol under established magnesium deficiency results in increasing of velocity of excretion of this analyte. In patient with diabetes mellitus type II six months before the diagnosis of this disease the hidden deficiency of magnesium was detected. The magnesium deficiency was not detected after the antidiabetic treatment was applied The results permit to postulate the possibility of application oral load test with magnesium to assess the impact of various stress, physical, emotional and psychological factors. The detection of magnesium deficiency permit to broad the complex treatment, to accelerate and to enhance the results of treatment of diseases. Besides, the evaluation of patient's condition according the reaction of the

  5. Acute diverticulitis of the sigmoid colon: value of ultrasound as an initial diagnostic test

    International Nuclear Information System (INIS)

    Garcia-Aguayo, F. J.; Gil, P. M.

    2002-01-01

    To assess the value of ultrasound as an initial diagnostic method in cases of acute diverticulitis. Ultrasound was carried out in 76 patients with a clinical diagnosis of acute sigmoid diverticulitis. The final diagnosis was based on the clinical course in every case, as well as on computed tomography (CT; n=46), histopathological examination (n=10), colonoscopy (n=4) and barium enema (n=2). The diagnostic criteria established for ultrasound was a thickening of the sigmoid colon wall of >4 mm and the presence of a least one of the following features: diverticular, phlegmon or abscess. The CT diagnosis was based on two indispensable findings: thickening of the sigmoid colon of>4 mm and inflammation of pericolonic fat. The final diagnosis was acute diverticulitis in 52 patients, some other disease in 18 and undetermined in 6. The sensitivities of ultrasound and CT were 81% and 94%, respectively, and their specificities were 79% and 83%, respectively. Of the 10 false negatives on ultrasound, seven corresponded to cases of simple diverticulitis and three to cases of complicated diverticulitis (two in patients with abscess and one in a patient with pneumoperitoneum). CT provided the correct diagnosis in eight of these cases, and resulted in false negatives in two cases of mild diverticulitis. Ultrasound is a valid test in the initial diagnosis of acute diverticulitis of the sigmoid colon. CT should be performed when ultrasound fails to provide a diagnosis or in cases of negative results when there is a strong clinical suspicion of diverticulitis, as well as when the possibility of complicated diverticulitis exists. (Author) 14 refs

  6. Sensitive Superconducting Gravity Gradiometer Constructed with Levitated Test Masses

    Science.gov (United States)

    Griggs, C. E.; Moody, M. V.; Norton, R. S.; Paik, H. J.; Venkateswara, K.

    2017-12-01

    We demonstrate basic operations of a two-component superconducting gravity gradiometer (SGG) that is constructed with a pair of magnetically levitated test masses coupled to superconducting quantum-interference devices. A design that gives a potential sensitivity of 1.4 ×10-4 E Hz-1 /2 (1 E ≡10-9 s-2 ) in the frequency band of 1 to 50 mHz and better than 2 ×10-5 E Hz-1 /2 between 0.1 and 1 mHz for a compact tensor SGG that fits within a 22-cm-diameter sphere. The SGG has the capability of rejecting the platform acceleration and jitter in all 6 degrees of freedom to one part in 109 . Such an instrument has applications in precision tests of fundamental laws of physics, earthquake early warning, and gravity mapping of Earth and the planets.

  7. DIAGNOSTIC VALUE OF PATCH TEST IN HAND AND FOOT ECZEMAS

    Directory of Open Access Journals (Sweden)

    Sravani Sandhya Bellam

    2016-11-01

    Full Text Available BACKGROUND The present study is undertaken to evaluate the results of patch test in 50 patients having hand and foot eczema attending skin OPD from October 2010 to September 2012 at KIMS, Narketpally. RESULTS Maximum number of cases in this study belong to 16-30 yrs. (46%.  In majority of cases, eczema was seen in both hands and feet (40%. Hand and foot eczema was commonly seen in construction workers (42.3%.  Mean duration of illness is 19.48 months.  42% of patients presented with acute eczema followed by subacute eczema (38% and then chronic eczema (20%.  Personal and family history of atopy was seen in only 4% and 6%, respectively.  Hand and foot eczema (42.3% was the commonest eczema followed by hand (30.74% and then foot eczema (11.53% and others (15.37%.  57.69% of patients are positive to more than one allergen and 42.3% were positive to single allergen.  Multiple allergens positivity is seen in construction workers (30.76%.  Potassium di chromate (28.5% is the common allergen found in patch test followed by Parthenium (16.6% followed by Paraphenylenediamine (14% and then Cobalt sulphate and Thiuram mix (9.5% and lastly Parabens mix, Nickel sulphate, Black rubber mix and Neomycin (4.7%.  Positive patch test is more commonly observed in patients having hands and or foot eczemas (42.30%. CONCLUSION Hand and foot eczema (42% was the commonest eczema followed by hand (30% and then foot eczema (11.5% and others (15.3%. Potassium dichromate is the commonest sensitiser (28.8%. We encountered a high degree of patch test positivity in our study group and the Indian standard series proved to be very useful.

  8. Odor-Specific Loss of Smell Sensitivity with Age as Revealed by the Specific Sensitivity Test.

    Science.gov (United States)

    Seow, Yi-Xin; Ong, Peter K C; Huang, Dejian

    2016-07-01

    The perception of odor mixtures plays an important role in human food intake, behavior, and emotions. Decline of smell acuity with normal aging could impact food perception and preferences at various ages. However, since the landmark Smell Survey by National Geographic, little has been elucidated on differences in the onset and extent of loss in olfactory sensitivity toward single odorants. Here, using the Specific Sensitivity test, we show the onset and extent of loss in both identification and detection thresholds of odorants with age are odorant-specific. Subjects of Chinese descent in Singapore (186 women, 95 men), aged 21-80 years, were assessed for olfactory sensitivity of 10 odorants from various odor groups. Notably, subjects in their 70s required 179 times concentration of rose-like odorant (2-phenylethanol) than subjects in the 20s, while thresholds for onion-like 2-methyloxolane-3-thiol only differed by 3 times between the age groups. In addition, identification rate for 2-phenylethanol was negatively correlated with age throughout adult life whereas mushroom-like oct-1-en-3-ol was equally identified by subjects across all ages. Our results demonstrated the girth of differentiated olfactory loss due to normal ageing, which potentially affect overall perception and preferences of odor mixtures with age. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Diagnostic Role of ECG Recording Simultaneously With EEG Testing.

    Science.gov (United States)

    Kendirli, Mustafa Tansel; Aparci, Mustafa; Kendirli, Nurten; Tekeli, Hakan; Karaoglan, Mustafa; Senol, Mehmet Guney; Togrol, Erdem

    2015-07-01

    Arrhythmia is not uncommon in the etiology of syncope which mimics epilepsy. Data about the epilepsy induced vagal tonus abnormalities have being increasingly reported. So we aimed to evaluate what a neurologist may gain by a simultaneous electrocardiogram (ECG) and electroencephalogram (EEG) recording in the patients who underwent EEG testing due to prediagnosis of epilepsy. We retrospectively evaluated and detected ECG abnormalities in 68 (18%) of 376 patients who underwent EEG testing. A minimum of 20 of minutes artifact-free recording were required for each patient. Standard 1-channel ECG was simultaneously recorded in conjunction with the EEG. In all, 28% of females and 14% of males had ECG abnormalities. Females (mean age 49 years, range 18-88 years) were older compared with the male group (mean age 28 years, range 16-83 years). Atrial fibrillation was more frequent in female group whereas bradycardia and respiratory sinus arrhythmia was higher in male group. One case had been detected a critical asystole indicating sick sinus syndrome in the female group and treated with a pacemaker implantation in the following period. Simultaneous ECG recording in conjunction with EEG testing is a clinical prerequisite to detect and to clarify the coexisting ECG and EEG abnormalities and their clinical relevance. Potentially rare lethal causes of syncope that mimic seizure or those that could cause resistance to antiepileptic therapy could effectively be distinguished by detecting ECG abnormalities coinciding with the signs and abnormalities during EEG recording. © EEG and Clinical Neuroscience Society (ECNS) 2014.

  10. State of the art in non-animal approaches for skin sensitization testing: from individual test methods towards testing strategies.

    Science.gov (United States)

    Ezendam, Janine; Braakhuis, Hedwig M; Vandebriel, Rob J

    2016-12-01

    The hazard assessment of skin sensitizers relies mainly on animal testing, but much progress is made in the development, validation and regulatory acceptance and implementation of non-animal predictive approaches. In this review, we provide an update on the available computational tools and animal-free test methods for the prediction of skin sensitization hazard. These individual test methods address mostly one mechanistic step of the process of skin sensitization induction. The adverse outcome pathway (AOP) for skin sensitization describes the key events (KEs) that lead to skin sensitization. In our review, we have clustered the available test methods according to the KE they inform: the molecular initiating event (MIE/KE1)-protein binding, KE2-keratinocyte activation, KE3-dendritic cell activation and KE4-T cell activation and proliferation. In recent years, most progress has been made in the development and validation of in vitro assays that address KE2 and KE3. No standardized in vitro assays for T cell activation are available; thus, KE4 cannot be measured in vitro. Three non-animal test methods, addressing either the MIE, KE2 or KE3, are accepted as OECD test guidelines, and this has accelerated the development of integrated or defined approaches for testing and assessment (e.g. testing strategies). The majority of these approaches are mechanism-based, since they combine results from multiple test methods and/or computational tools that address different KEs of the AOP to estimate skin sensitization potential and sometimes potency. Other approaches are based on statistical tools. Until now, eleven different testing strategies have been published, the majority using the same individual information sources. Our review shows that some of the defined approaches to testing and assessment are able to accurately predict skin sensitization hazard, sometimes even more accurate than the currently used animal test. A few defined approaches are developed to provide an

  11. Comparative evaluation of bivalent malaria rapid diagnostic tests versus traditional methods in field with special reference to heat stability testing in Central India.

    Directory of Open Access Journals (Sweden)

    Neeru Singh

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

  12. Genetic test utilization and diagnostic yield in adult patients with neurological disorders.

    Science.gov (United States)

    Bardakjian, Tanya M; Helbig, Ingo; Quinn, Colin; Elman, Lauren B; McCluskey, Leo F; Scherer, Steven S; Gonzalez-Alegre, Pedro

    2018-03-28

    To determine the diagnostic yield of different genetic test modalities in adult patients with neurological disorders, we evaluated all adult patients seen for genetic diagnostic evaluation in the outpatient neurology practice at the University of Pennsylvania between January 2016 and April 2017 as part of the newly created Penn Neurogenetics Program. Subjects were identified through our electronic medical system as those evaluated by the Program's single clinical genetic counselor in that period. A total of 377 patients were evaluated by the Penn Neurogenetics Program in different settings and genetic testing recommended. Of those, 182 (48%) were seen in subspecialty clinic setting and 195 (52%) in a General Neurogenetics Clinic. Genetic testing was completed in over 80% of patients in whom it was recommended. The diagnostic yield was 32% across disease groups. Stratified by testing modality, the yield was highest with directed testing (50%) and array comparative genomic hybridization (45%), followed by gene panels and exome testing (25% each). In conclusion, genetic testing can be successfully requested in clinic in a large majority of adult patients. Age is not a limiting factor for a genetic diagnostic evaluation and the yield of clinical testing across phenotypes (almost 30%) is consistent with previous phenotype-focused or research-based studies. These results should inform the development of specific guidelines for clinical testing and serve as evidence to improve reimbursement by insurance payers.

  13. Diagnostic efficacy of in vitro methods vs. skin testing in patients with inhalant allergies

    International Nuclear Information System (INIS)

    Corey, J.P.; Liudahl, J.J.; Young, S.A.; Rodman, S.M.

    1991-01-01

    The purpose of our study was to investigate the diagnostic efficacy of two selected methods of in vitro allergy testing. Specifically, the PRIST/modified RAST I125 isotope systems and the Quantizyme/modified EAST alkaline phosphatase method were compared. The time, expense, convenience, and diagnostic efficacy of the two procedures are discussed. Special attention is given to the practicality of each method for the practicing physician

  14. Comparative diagnostic value of the breath test and the urine test with 14C-urea in the detection of the Helicobacter pylori infection

    International Nuclear Information System (INIS)

    Kopanski, Z.; Jung, A.; Wasilewska-Radwanska, M.; Kuc, T.; Schlegel-Zawadzka, M.; Witkowska, B.

    2002-01-01

    Among 92 patients with chronic gastritis we conducted a synchronous diagnosis of the Helicobacter pylori (H. pylori) infection using a culture and a serological test (IFP), in conjunction with breath and urine tests involving 14 C-urea (BTU-C14 and UTU-C14). The infection was confirmed by isolation in 71 persons (77.2%), the presence of specific IgG in the blood serum was found in 75 (81.5%). In comparison, the BTU-C14 indicated a group of 77 people (83.7%) as infected, and the UTU-C14 a group of 76 (82.6%). In order to determine the diagnostic value (sensitivity, specificity and efficiency) of the latter tests, the results were compared with those of the culture and of the serological tests. It was found that the BTU-C14 test used showed a 100% sensitivity, a 89.5% specificity and a 97.9% efficiency. The UTU-C14 test showed a 100.0% sensitivity, a 94.4% specificity and a 98.9% efficiency in the detection of the H. pylori infection. (author)

  15. Temperature as a diagnostic for the drift scale test

    International Nuclear Information System (INIS)

    Lin, W; Wagoner, J; Ballard, S

    2000-01-01

    The United States Department of Energy (DOE) is investigating Yucca Mountain, Nevada, for its feasibility as a potential deep geological repository of high-level nuclear waste. In a deep geological repository, the radioactive decay heat released from high-level nuclear waste will heat up the rock mass. The heat will mobilize pore water in the rock mass by evaporation, and even boiling, if the thermal load is great enough. The water vapor/steam will flow away from the heat source because of pressure and thermal gradients and the effects of buoyancy force. The vapor/steam may flow along fractures or highly permeable zones and condense into liquid water in the cooler regions. Gravity and fracture network will control the drainage of the condensed water. Some of the water may flow back toward the waste package and reevaporated. This thermal-hydrological (TH) process will affect the amount of water that may come into contact with the waste package. Water is the main concern for the integrity of the waste package and the waste form, and the potential transport of radioactive nuclides. Thermally driven chemical and mechanical processes may affect the TH process. The coupled thermal-hydrological-mechanical-chemical (THMC) processes need to be understood before the performance of a repository can be adequately predicted. DOE is conducting field thermal tests to provide data for validating the model of the coupled THMC processes. Therefore, understanding the processes revealed by a field thermal test is essential for the model validation. This paper presents examples that temperature measurement is an effective tool for understanding the TH process

  16. Diagnostic Validity of Combining History Elements and Physical Examination Tests for Traumatic and Degenerative Symptomatic Meniscal Tears.

    Science.gov (United States)

    Décary, Simon; Fallaha, Michel; Frémont, Pierre; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Feldman, Debbie E; Sylvestre, Marie-Pierre; Vendittoli, Pascal-André; Desmeules, François

    2017-10-27

    The current approach to the clinical diagnosis of traumatic and degenerative symptomatic meniscal tears (SMTs) proposes combining history elements and physical examination tests without systematic prescription of imaging investigations, yet the evidence to support this diagnostic approach is scarce. To assess the validity of diagnostic clusters combining history elements and physical examination tests to diagnose or exclude traumatic and degenerative SMT compared with other knee disorders. Prospective diagnostic accuracy study. Patients were recruited from 2 orthopedic clinics, 2 family medicine clinics, and from a university community. A total of 279 consecutive patients who underwent consultation for a new knee complaint. Each patient was assessed independently by 2 evaluators. History elements and standardized physical examination tests performed by a physiotherapist were compared with the reference standard: an expert physicians' composite diagnosis including a clinical examination and confirmatory magnetic resonance imaging. Participating expert physicians were orthopedic surgeons (n = 3) or sport medicine physicians (n = 2). Penalized logistic regression (least absolute shrinkage and selection operator) was used to identify history elements and physical examination tests associated with the diagnosis of SMT and recursive partitioning was used to develop diagnostic clusters. Diagnostic accuracy measures were calculated including sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios (LR+/-) with associated 95% confidence intervals (CIs). Eighty patients had a diagnosis of SMT (28.7%), including 35 traumatic tears and 45 degenerative tears. The combination a history of trauma during a pivot, medial knee pain location, and a positive medial joint line tenderness test was able to diagnose (LR+ = 8.9; 95% CI 6.1-13.1) or exclude (LR- = 0.10; 95% CI 0.03-0.28) a traumatic SMT. Combining a history of

  17. Zagreb Amblyopia Preschool Screening Study: near and distance visual acuity testing increase the diagnostic accuracy of screening for amblyopia.

    Science.gov (United States)

    Bušić, Mladen; Bjeloš, Mirjana; Petrovečki, Mladen; Kuzmanović Elabjer, Biljana; Bosnar, Damir; Ramić, Senad; Miletić, Daliborka; Andrijašević, Lidija; Kondža Krstonijević, Edita; Jakovljević, Vid; Bišćan Tvrdi, Ana; Predović, Jurica; Kokot, Antonio; Bišćan, Filip; Kovačević Ljubić, Mirna; Motušić Aras, Ranka

    2016-02-01

    To present and evaluate a new screening protocol for amblyopia in preschool children. Zagreb Amblyopia Preschool Screening (ZAPS) study protocol performed screening for amblyopia by near and distance visual acuity (VA) testing of 15 648 children aged 48-54 months attending kindergartens in the City of Zagreb County between September 2011 and June 2014 using Lea Symbols in lines test. If VA in either eye was >0.1 logMAR, the child was re-tested, if failed at re-test, the child was referred to comprehensive eye examination at the Eye Clinic. 78.04% of children passed the screening test. Estimated prevalence of amblyopia was 8.08%. Testability, sensitivity, and specificity of the ZAPS study protocol were 99.19%, 100.00%, and 96.68% respectively. The ZAPS study used the most discriminative VA test with optotypes in line as they do not underestimate amblyopia. The estimated prevalence of amblyopia was considerably higher than reported elsewhere. To the best of our knowledge, the ZAPS study protocol reached the highest sensitivity and specificity when evaluating diagnostic accuracy of VA tests for screening. The pass level defined at ≤0.1 logMAR for 4-year-old children, using Lea Symbols in lines missed no amblyopia cases, advocating that both near and distance VA testing should be performed when screening for amblyopia.

  18. Structured approach to design of diagnostic test evaluation studies for chronic progressive infections in animals

    DEFF Research Database (Denmark)

    Nielsen, Søren Saxmose; Toft, Nils; Gardner, Ian Andrew

    2011-01-01

    ) than originally intended. The objective of this paper is to outline a structured approach to the design and conduct of a DTE for diagnostic tests used for chronic infections in animals, and intended for different purposes. We describe the process from reflections about test purpose and the underlying......Diagnostic test evaluations (DTEs) for chronic infections are challenging because a protracted incubation period has to be considered in the design of the DTE, and the adverse effects of infection may be widespread and progressive over an animal's entire life. Frequently, the specific purpose...

  19. More Than Just Accuracy: A Novel Method to Incorporate Multiple Test Attributes in Evaluating Diagnostic Tests Including Point of Care Tests.

    Science.gov (United States)

    Thompson, Matthew; Weigl, Bernhard; Fitzpatrick, Annette; Ide, Nicole

    2016-01-01

    Current frameworks for evaluating diagnostic tests are constrained by a focus on diagnostic accuracy, and assume that all aspects of the testing process and test attributes are discrete and equally important. Determining the balance between the benefits and harms associated with new or existing tests has been overlooked. Yet, this is critically important information for stakeholders involved in developing, testing, and implementing tests. This is particularly important for point of care tests (POCTs) where tradeoffs exist between numerous aspects of the testing process and test attributes. We developed a new model that multiple stakeholders (e.g., clinicians, patients, researchers, test developers, industry, regulators, and health care funders) can use to visualize the multiple attributes of tests, the interactions that occur between these attributes, and their impacts on health outcomes. We use multiple examples to illustrate interactions between test attributes (test availability, test experience, and test results) and outcomes, including several POCTs. The model could be used to prioritize research and development efforts, and inform regulatory submissions for new diagnostics. It could potentially provide a way to incorporate the relative weights that various subgroups or clinical settings might place on different test attributes. Our model provides a novel way that multiple stakeholders can use to visualize test attributes, their interactions, and impacts on individual and population outcomes. We anticipate that this will facilitate more informed decision making around diagnostic tests.

  20. Comparison of agar gel immunodiffusion test, enzyme-linked immunosorbent assay and PCR in diagnostics of enzootic bovine leukosis

    Directory of Open Access Journals (Sweden)

    Malovrh Tadej

    2005-01-01

    Full Text Available Bovine leukaemia virus (BLV is a retrovirus that induces a chronic infection in cattle. Once infected, cattle remain virus carriers for life and start to show an antibody response within a few weeks after infection. Eradication and control of the disease are based on early diagnostics and segregation of the carriers. The choice of a diagnostic method depends on the eradication programme, money resources and characteristics of the herd to be analysed. The agar gel immunodiffusion (AGID test has been the serological test of choice for routine diagnosis of serum samples. Nevertheless, in more recent years, the enzyme-linked immunosorbent assay (ELISA has replaced the AGID for large scale testing. For this purpose, commercially available BLV-ELISA kits were compared to the AGID and to the polymerase chain reaction (PCR method performed with two sets of primers, amplifying env region. The ELISA kit based on the p24 core protein was found to be less specific and served as a screening test. The ELISA kit based on the envelope glycoprotein (gpSI served as a verification test and gave a good correlation with the AGID test and PCR method. However, ELISA showed a higher sensitivity than AGID. The p24 based ELiSA was useful for screening a large number of samples, whereas gp51 based ELISA, AGID and PCR were more important for detecting the antibody response against the individual BLV-proteins and therefore for verification of the infection with BLV.

  1. California mastitis test in the diagnostic of subclinical mastitis

    Directory of Open Access Journals (Sweden)

    Adna Crisléia Rodrigues Monção de Lima

    2013-12-01

    Full Text Available Milk production in Brazil is undoubtedly one of the most important Brazilian agroindustrial complex. Moves large sums of money, the dairy industry employs millions of the people, having potential to provide the domestic and foreign markets. Besides surpassing year by year the index production. The quality of milk is increasingly demanded by consumers and there are bonus programs for milk with low somatic cell counts, which reveal, indirectely, the udder sanity. Mastitis, the udder inflamation, is the main factor that substantially compromises the milk quality. Several methods can diagnose the incidence of subclinical mastitis in dairy herds. One these methods, the California Mastitis Test (CMT has as advantages being practical, low cost and the results are immediately available. The CMT method consists of adding the anionic neutral detergent to a milk sample in order to disrupt milk somatic cell membranes and release nucleic material. The viscousity formed by this reaction allows estimating the number of somatic cells (immunity cells presents in the milk. According to the degree of gelatinization obtained in this reaction, the interpretation of the scores varies from zero, no viscosity, to three crosses, highly viscous. This study was aimed to evaluate the CMT of eight dairy herds of different farms in Sao Paulo state, described by the letters A to H. The scores 1, 2 and 3 were considered positive for subclinical mastitis, while 0 was negative. The results were determined in relative frequency (%. It is evident that the herd D is the most affected by subclinical mastitis, because of the greater number of CMT positive (60%. This may be due to the mismanagement and poor conditions of milking. The properties C, F and G require greater attention, as the result of CMT could corroborate the presence of pathogenic microorganisms and infected cows can quickly transmit the infection to the healthy ones. Note that the farms A, B and H are the ones with

  2. The Green Propellant Infusion Mission Thruster Performance Testing for Plume Diagnostics

    Science.gov (United States)

    Deans, Matthew C.; Reed, Brian D.; Arrington, Lynn A.; Williams, George J.; Kojima, Jun J.; Kinzbach, McKenzie I.; McLean, Christopher H.

    2014-01-01

    The Green Propellant Infusion Mission (GPIM) is sponsored by NASA's Space Technology Mission Directorate (STMD) Technology Demonstration Mission (TDM) office. The goal of GPIM is to advance the technology readiness level of a green propulsion system, specifically, one using the monopropellant, AF-M315E, by demonstrating ground handling, spacecraft processing, and on-orbit operations. One of the risks identified for GPIM is potential contamination of sensitive spacecraft surfaces from the effluents in the plumes of AF-M315E thrusters. NASA Glenn Research Center (GRC) is conducting activities to characterize the effects of AF-M315E plume impingement and deposition. GRC has established individual plume models of the 22-N and 1-N thrusters that will be used on the GPIM spacecraft. The model simulations will be correlated with plume measurement data from Laboratory and Engineering Model 22-N, AF-M315E thrusters. The thrusters are currently being tested in a small rocket, altitude facility at NASA GRC. A suite of diagnostics, including Raman spectroscopy, Rayleigh spectroscopy, and Schlieren imaging are being used to acquire plume measurements of AF-M315E thrusters. Plume data will include temperature, velocity, relative density, and species concentration. The plume measurement data will be compared to the corresponding simulations of the plume model. The GRC effort will establish a data set of AF-M315E plume measurements and a plume model that can be used for future AF-M315E applications.

  3. The usefulness of rapid diagnostic tests in the new context of low malaria transmission in Zanzibar.

    Science.gov (United States)

    Shakely, Delér; Elfving, Kristina; Aydin-Schmidt, Berit; Msellem, Mwinyi I; Morris, Ulrika; Omar, Rahila; Weiping, Xu; Petzold, Max; Greenhouse, Bryan; Baltzell, Kimberly A; Ali, Abdullah S; Björkman, Anders; Mårtensson, Andreas

    2013-01-01

    We assessed if histidine-rich-protein-2 (HRP2) based rapid diagnostic test (RDT) remains an efficient tool for Plasmodium falciparum case detection among fever patients in Zanzibar and if primary health care workers continue to adhere to RDT results in the new epidemiological context of low malaria transmission. Further, we evaluated the performance of RDT within the newly adopted integrated management of childhood illness (IMCI) algorithm in Zanzibar. We enrolled 3890 patients aged ≥ 2 months with uncomplicated febrile illness in this health facility based observational study conducted in 12 primary health care facilities in Zanzibar, between May-July 2010. One patient had an inconclusive RDT result. Overall 121/3889 (3.1%) patients were RDT positive. The highest RDT positivity rate, 32/528 (6.1%), was found in children aged 5-14 years. RDT sensitivity and specificity against PCR was 76.5% (95% CI 69.0-83.9%) and 99.9% (95% CI 99.7-100%), and against blood smear microscopy 78.6% (95% CI 70.8-85.1%) and 99.7% (95% CI 99.6-99.9%), respectively. All RDT positive, but only 3/3768 RDT negative patients received anti-malarial treatment. Adherence to RDT results was thus 3887/3889 (99.9%). RDT performed well in the IMCI algorithm with equally high adherence among children Zanzibar. ClinicalTrials.gov NCT01002066.

  4. [Vasculitic Peripheral Neuropathies: Clinical Features and Diagnostic Laboratory Tests].

    Science.gov (United States)

    Ogata, Katsuhisa

    2016-03-01

    Vasculitic peripheral neuropathy (VPN) occurs due to ischemic changes of peripheral nerves, resulting from a deficit of vascular blood supply due to damaged vasa nervorum leading to vasculitis. VPN usually manifests as sensorimotor or sensory disturbances accompanied by pain, presenting as a type of multiple mononeuropathy, with a scattered distribution in distal limbs. VPN may also present as a mononeuropathy, distal symmetric polyneuropathy, plexopathy, or radiculopathy. The rapidity of VPN is variable, ranging from days to months, with symptoms occasionally changing with the appearance of new lesions. Careful history taking and neurological examination provides an exact diagnosis. The most common cause of VPN is primary vasculitis predominantly affecting small vessels, including vasa nervorum, anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, and polyarteritis nodosa. Similar vasculitic processes can also result from a systemic collagen disorder or secondary vasculitis. Electrophysiological studies and pathological investigation of biopsied peripheral nerves and muscles are important for diagnosis of vasculitis. Serological tests, including ANCA, are useful for diagnosis of vasculitis. Accurate neurological examinations are essential for diagnosis and evaluation of clinical course.

  5. Escalating Health Care Cost due to Unnecessary Diagnostic Testing

    Directory of Open Access Journals (Sweden)

    MUHAMMAD AZAM ISHAQUE CHAUDHARY

    2017-07-01

    Full Text Available Focusing on health care systems can improve health outcomes now and in the future. Growing economies have serious concerns on the rising cost of health, whereas, in under developed countries like Pakistan, it is not emphasized yet at all. The research is conducted to improve a unique aspect of health care systems to provide effective, patient-centred, high-standard health care while maintaining the cost effectiveness. Research is being qualified in two paradigms qualitative and quantitative. In qualitative research, expert?s interviews have been taken to get the basic knowledge of radiology based testing and their prerequisites, in quantitative research ordered are being analysed to check the frequency and if they are unnecessary or qualified medical necessity guidelines as established in qualitative method. Analysis was made on the basis of the trinity relationship of diagnosis, symptoms and respected order to determine the necessity of the order to get its impact on cost of the overall health of those patients and point out more than 50% unnecessary orders are being performed in two government hospitals. The situation is alarming and policy makers should focus on unnecessary ordering to avoid out of pocket expenses and improve quality of care. The research helps in successful application of health care system modifications and policies pertaining to one aspect of health systems, i.e. cost-effectiveness of health care.

  6. 42 CFR 414.509 - Reconsideration of basis for and amount of payment for a new clinical diagnostic laboratory test.

    Science.gov (United States)

    2010-10-01

    ... for a new clinical diagnostic laboratory test. 414.509 Section 414.509 Public Health CENTERS FOR... FOR PART B MEDICAL AND OTHER HEALTH SERVICES Payment for New Clinical Diagnostic Laboratory Tests § 414.509 Reconsideration of basis for and amount of payment for a new clinical diagnostic laboratory...

  7. Consensus based reporting standards for diagnostic test accuracy studies for paratuberculosis in ruminants.

    NARCIS (Netherlands)

    Gardner, I.A.; Nielsen, S.S.; Whittington, R.J.; Collins, M.T.; Bakker, D.; Harris, B.; Sreevatsan, S.; Lombard, J.E.; Sweeney, R.; Smith, D.R.; Gavalchin, J.; Eda, S.

    2011-01-01

    The Standards for Reporting of Diagnostic Accuracy (STARD) statement (www.stard-statement.org) was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy studies

  8. Evaluating operational specifications of point-of-care diagnostic tests: a standardized scorecard.

    Directory of Open Access Journals (Sweden)

    Jonathan D Lehe

    Full Text Available The expansion of HIV antiretroviral therapy into decentralized rural settings will increasingly require simple point-of-care (POC diagnostic tests that can be used without laboratory infrastructure and technical skills. New POC test devices are becoming available but decisions around which technologies to deploy may be biased without systematic assessment of their suitability for decentralized healthcare settings. To address this, we developed a standardized, quantitative scorecard tool to objectively evaluate the operational characteristics of POC diagnostic devices. The tool scores devices on a scale of 1-5 across 30 weighted characteristics such as ease of use, quality control, electrical requirements, shelf life, portability, cost and service, and provides a cumulative score that ranks products against a set of ideal POC characteristics. The scorecard was tested on 19 devices for POC CD4 T-lymphocyte cell counting, clinical chemistry or hematology testing. Single and multi-parameter devices were assessed in each of test categories. The scores across all devices ranged from 2.78 to 4.40 out of 5. The tool effectively ranked devices within each category (p0.80; p<0.001. Use of this tool enables the systematic evaluation of diagnostic tests to facilitate product selection and investment in appropriate technology. It is particularly relevant for countries and testing programs considering the adoption of new POC diagnostic tests.

  9. Accuracy of diagnostic tests for clinically suspected upper extremity deep vein thrombosis: a systematic review

    NARCIS (Netherlands)

    Di Nisio, M.; van Sluis, G. L.; Bossuyt, P. M. M.; Büller, H. R.; Porreca, E.; Rutjes, A. W. S.

    2010-01-01

    Background: The best available test for the diagnosis of upper extremity deep venous thrombosis (UEDVT) is contrast venography. The aim of this systematic review was to assess whether the diagnostic accuracy of other tests for clinically suspected UEDVT is high enough to justify their use in

  10. Diagnostic and prognostic implications of exercise testing in coronary artery disease

    NARCIS (Netherlands)

    J.W. Deckers (Jaap)

    1988-01-01

    textabstractThe clinical indications for exercise testing as a diagnostic and prognostic tool in the assessment of patients with ischemic heart disease have gradually evolved since Master introduced the two-step exercise test in 1929 (1). New information from correlations between

  11. Lessons learned developing a diagnostic tool for HIV-associated dementia feasible to implement in resource-limited settings: pilot testing in Kenya.

    Directory of Open Access Journals (Sweden)

    Judith Kwasa

    Full Text Available To conduct a preliminary evaluation of the utility and reliability of a diagnostic tool for HIV-associated dementia (HAD for use by primary health care workers (HCW which would be feasible to implement in resource-limited settings.In resource-limited settings, HAD is an indication for anti-retroviral therapy regardless of CD4 T-cell count. Anti-retroviral therapy, the treatment for HAD, is now increasingly available in resource-limited settings. Nonetheless, HAD remains under-diagnosed likely because of limited clinical expertise and availability of diagnostic tests. Thus, a simple diagnostic tool which is practical to implement in resource-limited settings is an urgent need.A convenience sample of 30 HIV-infected outpatients was enrolled in Western Kenya. We assessed the sensitivity and specificity of a diagnostic tool for HAD as administered by a primary HCW. This was compared to an expert clinical assessment which included examination by a physician, neuropsychological testing, and in selected cases, brain imaging. Agreement between HCW and an expert examiner on certain tool components was measured using Kappa statistic.The sample was 57% male, mean age was 38.6 years, mean CD4 T-cell count was 323 cells/µL, and 54% had less than a secondary school education. Six (20% of the subjects were diagnosed with HAD by expert clinical assessment. The diagnostic tool was 63% sensitive and 67% specific for HAD. Agreement between HCW and expert examiners was poor for many individual items of the diagnostic tool (K = .03-.65. This diagnostic tool had moderate sensitivity and specificity for HAD. However, reliability was poor, suggesting that substantial training and formal evaluations of training adequacy will be critical to enable HCW to reliably administer a brief diagnostic tool for HAD.

  12. Hui and Walter's latent-class model extended to estimate diagnostic test properties from surveillance data: a latent model for latent data.

    Science.gov (United States)

    Bermingham, Mairead L; Handel, Ian G; Glass, Elizabeth J; Woolliams, John A; de Clare Bronsvoort, B Mark; McBride, Stewart H; Skuce, Robin A; Allen, Adrian R; McDowell, Stanley W J; Bishop, Stephen C

    2015-07-07

    Diagnostic test sensitivity and specificity are probabilistic estimates with far reaching implications for disease control, management and genetic studies. In the absence of 'gold standard' tests, traditional Bayesian latent class models may be used to assess diagnostic test accuracies through the comparison of two or more tests performed on the same groups of individuals. The aim of this study was to extend such models to estimate diagnostic test parameters and true cohort-specific prevalence, using disease surveillance data. The traditional Hui-Walter latent class methodology was extended to allow for features seen in such data, including (i) unrecorded data (i.e. data for a second test available only on a subset of the sampled population) and (ii) cohort-specific sensitivities and specificities. The model was applied with and without the modelling of conditional dependence between tests. The utility of the extended model was demonstrated through application to bovine tuberculosis surveillance data from Northern and the Republic of Ireland. Simulation coupled with re-sampling techniques, demonstrated that the extended model has good predictive power to estimate the diagnostic parameters and true herd-level prevalence from surveillance data. Our methodology can aid in the interpretation of disease surveillance data, and the results can potentially refine disease control strategies.

  13. Testing the Perturbation Sensitivity of Abortion-Crime Regressions

    Directory of Open Access Journals (Sweden)

    Michał Brzeziński

    2012-06-01

    Full Text Available The hypothesis that the legalisation of abortion contributed significantly to the reduction of crime in the United States in 1990s is one of the most prominent ideas from the recent “economics-made-fun” movement sparked by the book Freakonomics. This paper expands on the existing literature about the computational stability of abortion-crime regressions by testing the sensitivity of coefficients’ estimates to small amounts of data perturbation. In contrast to previous studies, we use a new data set on crime correlates for each of the US states, the original model specifica-tion and estimation methodology, and an improved data perturbation algorithm. We find that the coefficients’ estimates in abortion-crime regressions are not computationally stable and, therefore, are unreliable.

  14. Development of an umami taste sensitivity test and its clinical use.

    Directory of Open Access Journals (Sweden)

    Shizuko Satoh-Kuriwada

    Full Text Available There is a close relationship between perception of umami, which has become recognized as the fifth taste, and the human physical condition. We have developed a clinical test for umami taste sensitivity using a filter paper disc with a range of six monosodium glutamate (MSG concentrations. We recruited 28 patients with taste disorders (45-78 years and 184 controls with no taste disorders (102 young [18-25 years] and 82 older [65-89 years] participants. Filter paper discs (5 mm dia. were soaked in aqueous MSG solutions (1, 5, 10, 50, 100 and 200 mM, then placed on three oral sites innervated by different taste nerves. The lowest concentration participants correctly identified was defined as the recognition threshold (RT for MSG. This test showed good reproducibility for inter- and intra-observer variability. We concluded that: (1 The RT of healthy controls differed at measurement sites innervated by different taste nerves; that is, the RT of the anterior tongue was higher than that of either the posterior tongue or the soft palate in both young and older individuals. (2 No significant difference in RT was found between young adults and older individuals at any measurement site. (3 The RT of patients with taste disorders was higher before treatment than that of the healthy controls at any measurement site. (4 The RT after treatment in these patients improved to the same level as that of the healthy controls. (5 The cutoff values of RT, showing the highest diagnostic accuracy (true positives + true negatives, were 200 mM MSG for AT and 50 mM MSG for PT and SP. The diagnostic accuracy at these cutoff values was 0.92, 0.87 and 0.86 for AT, PT and SP, respectively. Consequently, this umami taste sensitivity test is useful for discriminating between normal and abnormal umami taste sensations.

  15. High sensitivity and specificity in proposed clinical diagnostic criteria for anti-N-methyl-D-aspartate receptor encephalitis.

    Science.gov (United States)

    Ho, Alvin C C; Mohammad, Shekeeb S; Pillai, Sekhar C; Tantsis, Esther; Jones, Hannah; Ho, Reena; Lim, Ming; Hacohen, Yael; Vincent, Angela; Dale, Russell C

    2017-12-01

    To determine the validity of the proposed clinical diagnostic criteria for anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis in paediatric patients. The diagnostic criteria for anti-NMDAR encephalitis proposed by Graus et al. (2016) use clinical features and conventional investigations to facilitate early immunotherapy before antibody status is available. The criteria are satisfied if patients develop four out of six symptom groups within 3 months, together with at least one abnormal investigation (electroencephalography/cerebrospinal fluid) and reasonable exclusion of other disorders. We evaluated the validity of the criteria using a retrospective cohort of paediatric patients with encephalitis. Twenty-nine patients with anti-NMDAR encephalitis and 74 comparison children with encephalitis were included. As expected, the percentage of patients with anti-NMDAR encephalitis who fulfilled the clinical criteria increased over time. During the hospital inpatient admission, most patients (26/29, 90%) with anti-NMDAR encephalitis fulfilled the criteria, significantly more than the comparison group (3/74, 4%) (panti-NMDAR encephalitis was 2 weeks from first symptom onset (range 1-6). The sensitivity of the criteria was 90% (95% confidence interval 73-98) and the specificity was 96% (95% confidence interval 89-99). The proposed diagnostic criteria for anti-NMDAR encephalitis have good sensitivity and specificity. Incomplete criteria do not exclude the diagnosis. The proposed clinical diagnostic criteria for anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis by Graus et al. (2016) have high sensitivity and specificity in paediatric patients. The median time of fulfilling the criteria in patients with anti-NMDAR was 2 weeks from first symptom onset. © 2017 Mac Keith Press.

  16. Modification of two capripoxvirus quantitative real-time PCR assays to improve diagnostic sensitivity and include beta-actin as an internal positive control.

    Science.gov (United States)

    Das, Amaresh; Deng, Ming Y; Babiuk, Shawn; McIntosh, Michael T

    2017-05-01

    Capripoxviruses (CaPVs), consisting of Sheeppox virus (SPV), Goatpox virus (GPV), and Lumpy skin disease virus (LSDV) species, cause economically significant diseases in sheep, goats, and cattle, respectively. Quantitative real-time polymerase chain reaction (qPCR) assays are routinely used for rapid detection of CaPVs in surveillance and outbreak management programs. We further modified and optimized 2 previously published CaPV qPCR assays, referred to as the Balinsky and Bowden assays, by changing commercial PCR reagents used in the tests. The modified assays displayed 100% analytical specificity and showed no apparent changes in analytical sensitivities for detection of CaPVs compared with the original assays. Diagnostic sensitivities, assessed using 50 clinical reference samples from experimentally infected sheep, goats, and cattle, improved from 82% to 92% for the modified Balinsky assay and from 58% to 82% for the modified Bowden assay. The modified qPCR assays were multiplexed for detection of beta-actin as an indicator for potential false-negative results. The multiplex modified qPCR assays exhibited the same diagnostic sensitivities as the singleplex assays suggesting their utility in the detection of CaPVs.

  17. Joint line tenderness and McMurray tests for the detection of meniscal lesions: what is their real diagnostic value?

    Science.gov (United States)

    Galli, Marco; Ciriello, Vincenzo; Menghi, Amerigo; Aulisa, Angelo G; Rabini, Alessia; Marzetti, Emanuele

    2013-06-01

    To assess the interobserver concordance of the joint line tenderness (JLT) and McMurray tests, and to determine their diagnostic efficiency for the detection of meniscal lesions. Prospective observational study. Orthopedics outpatient clinic, university hospital. Patients (N=60) with suspected nonacute meniscal lesions who underwent knee arthroscopy. Not applicable. Patients were examined by 3 independent observers with graded levels of experience (>10y, 3y, and 4mo of practice). The interobserver concordance was assessed by Cohen-Fleiss κ statistics. Accuracy, negative and positive predictive values for prevalence 10% to 90%, positive (LR+) and negative (LR-) likelihood ratios, and the Bayesian posttest probability with a positive or negative result were also determined. The diagnostic value of the 2 tests combined was assessed by logistic regression. Arthroscopy was used as the reference test. No interobserver concordance was determined for the JLT. The McMurray test showed higher interobserver concordance, which improved when judgments by the less experienced examiner were discarded. The whole series studied by the "best" examiner (experienced orthopedist) provided the following values: (1) JLT: sensitivity, 62.9%; specificity, 50%; LR+, 1.26; LR-, .74; (2) McMurray: sensitivity, 34.3%; specificity, 86.4%; LR+, 2.52; LR-, .76. The combination of the 2 tests did not offer advantages over the McMurray alone. The JLT alone is of little clinical usefulness. A negative McMurray test does not modify the pretest probability of a meniscal lesion, while a positive result has a fair predictive value. Hence, in a patient with a suspected meniscal lesion, a positive McMurray test indicates that arthroscopy should be performed. In case of a negative result, further examinations, including imaging, are needed. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. Optimal Sequential Diagnostic Strategy Generation Considering Test Placement Cost for Multimode Systems

    Directory of Open Access Journals (Sweden)

    Shigang Zhang

    2015-10-01

    Full Text Available Sequential fault diagnosis is an approach that realizes fault isolation by executing the optimal test step by step. The strategy used, i.e., the sequential diagnostic strategy, has great influence on diagnostic accuracy and cost. Optimal sequential diagnostic strategy generation is an important step in the process of diagnosis system construction, which has been studied extensively in the literature. However, previous algorithms either are designed for single mode systems or do not consider test placement cost. They are not suitable to solve the sequential diagnostic strategy generation problem considering test placement cost for multimode systems. Therefore, this problem is studied in this paper. A formulation is presented. Two algorithms are proposed, one of which is realized by system transformation and the other is newly designed. Extensive simulations are carried out to test the effectiveness of the algorithms. A real-world system is also presented. All the results show that both of them have the ability to solve the diagnostic strategy generation problem, and they have different characteristics.

  19. Mathematics diagnostic testing in engineering: an international comparison between Ireland and Portugal

    Science.gov (United States)

    Carr, M.; Fidalgo, C.; Bigotte de Almeida, M. E.; Branco, J. R.; Santos, V.; Murphy, E.; Fhloinn, E. Ní

    2015-09-01

    Concern has been expressed throughout Europe about the significant deficiencies in the basic mathematical skills of many engineering undergraduates. Mathematics diagnostic tests in the UK, Ireland and Portugal have shown these shortcomings, which provide a challenge to those striving to introduce more innovative educational practices into engineering education, such as projects or real-world problems. Every year, in the Dublin Institute of Technology (Ireland) and the Instituto Superior de Engenharia de Coimbra (Portugal), a diagnostic test is given to incoming first-year students. A comparison showed some potentially interesting differences between these students. In September 2013, a project was undertaken to compare mathematical competencies of incoming engineering students in both countries. A modified diagnostic test was devised and the results were then compared to ascertain if there are common areas of difficulty between students in Ireland and Portugal, or evidence of one group significantly outperforming the other in a particular area.

  20. On the use of sensitivity tests in seismic tomography

    Science.gov (United States)

    Rawlinson, N.; Spakman, W.

    2016-05-01

    Sensitivity analysis with synthetic models is widely used in seismic tomography as a means for assessing the spatial resolution of solutions produced by, in most cases, linear or iterative nonlinear inversion schemes. The most common type of synthetic reconstruction test is the so-called checkerboard resolution test in which the synthetic model comprises an alternating pattern of higher and lower wave speed (or some other seismic property such as attenuation) in 2-D or 3-D. Although originally introduced for application to large inverse problems for which formal resolution and covariance could not be computed, these tests have achieved popularity, even when resolution and covariance can be computed, by virtue of being simple to implement and providing rapid and intuitive insight into the reliability of the recovered model. However, checkerboard tests have a number of potential drawbacks, including (1) only providing indirect evidence of quantitative measures of reliability such as resolution and uncertainty, (2) giving a potentially misleading impression of the range of scale-lengths that can be resolved, and (3) not giving a true picture of the structural distortion or smearing that can be caused by the data coverage. The widespread use of synthetic reconstruction tests in seismic tomography is likely to continue for some time yet, so it is important to implement best practice where possible. The goal of this paper is to develop the underlying theory and carry out a series of numerical experiments in order to establish best practice and identify some common pitfalls. Based on our findings, we recommend (1) the use of a discrete spike test involving a sparse distribution of spikes, rather than the use of the conventional tightly spaced checkerboard; (2) using data coverage (e.g. ray-path geometry) inherited from the model constrained by the observations (i.e. the same forward operator or matrix), rather than the data coverage obtained by solving the forward problem

  1. Sensory-processing sensitivity in social anxiety disorder: Relationship to harm avoidance and diagnostic subtypes

    OpenAIRE

    Hofmann, Stefan G.; Bitran, Stella

    2006-01-01

    Sensory-processing sensitivity is assumed to be a heritable vulnerability factor for shyness. The present study is the first to examine sensory-processing sensitivity among individuals with social anxiety disorder. The results showed that the construct is separate from social anxiety, but it is highly correlated with harm avoidance and agoraphobic avoidance. Individuals with a generalized subtype of social anxiety disorder reported higher levels of sensory-processing sensitivity than individu...

  2. Diagnostic performance of placental alpha-microglobulin-1 test in women with prolonged pre-labour rupture of membranes.

    Science.gov (United States)

    Eleje, George Uchenna; Ezugwu, Euzebus Chinonye; Eke, Ahizechukwu Chigoziem; Eleje, Lydia Ijeoma; Ikechebelu, Joseph Ifeanyichukwu; Afiadigwe, Evaristus Anthony; Ezugwu, Frank O; Udigwe, Gerald Okanandu; Okafor, Charles I; Ezeama, Chukwuemeka Okwudili

    2016-01-01

    To determine diagnostic performance of placental alpha-microglobulin-1 (PAMG-1) test compared to conventional clinical assessment (CCA) in women with prolonged pre-labour rupture of membranes (PROM). A double-blind study of women with symptoms and signs of PROM in Nnamdi Azikiwe University Teaching Hospital, Nnewi and University of Nigeria Teaching Hospital, Enugu, in south-east Nigeria using CCA for PROM and PAMG-1 test was done. Women were included if their symptoms, signs or complaints suggestive of PROM was more than 24 h duration. PROM was diagnosed if two out of three methods from CCA (pooling, positive nitrazine test or ferning) were present. Confirmation of PROM was done after delivery using any two of these clinical criteria: delivery in 48 h to 7 days, evidence of chorioamnionitis, membranes obviously ruptured at delivery and adverse perinatal outcomes strongly correlated with prolonged PROM. Accuracy, specificity and sensitivity value for CCA were 72.5, 36.8 and 86.0% lower than for PAMG-1 test which were 95.7, 94.1 and 96.2%. In equivocal cases, PAMG-1 was significantly more accurate than CCA (92.3% versus 38.5%; p < 0.001). This study in women with prolonged PROM, confirms that PAMG-1 test has high diagnostic accuracy irrespective of the duration of PROM before clinical evaluation.

  3. [Evaluation of a rapid diagnostic test in the diagnosis of toxoplasmosis in pregnant women in Cotonou (Bénin)].

    Science.gov (United States)

    Ogouyèmi-Hounto, A; Agbayahoun-Chokki, F; Sissinto Savi de Tove, Y; Biokou Bankole, B; Adinsi de Souza, V; Assogba, M; Kinde-Gazard, D; Massougbodji, A

    2014-05-01

    The aim of the study was to evaluate the performance of the ImmunoComb® Toxo IgG and ImmunoComb® Toxo IgMassays (rapid diagnostic test) in the laboratory diagnosis of toxoplasmosis in pregnant women in Cotonou. We interviewed 266 pregnant women, who first answered an epidemiological questionnaire, and collected blood samples for measurement of IgG and IgM anti T. gondii antibodies with the ImmunoComb toxo assays and with the ARCHITECT CIMA method. The sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV) were calculated to determine the performance of the rapid test. The seroprevalences of IgG against T. gondii by CIMA technique and rapid test were respectively 48.9% and 48.5%. The prevalence increased with age. Performances for IgG were: sensitivity 97%, specificity 100%, PPV 100%, NPV = 97.10%. For IgM, Sensitivity: 33.3% Specificity: 100%, PPV 100%, NPV = 99.2%. Seroprevalence obtained shows that about half of the study population is not immune against T. gondii and requires regular serological monitoring until delivery. According to these results, and given the needs of toxoplasmosis diagnosis on the field characterized by an important decrease of immunized women, this test may be recommended in the laboratory diagnosis of toxoplasmosis in peripheral levels of the health pyramid.

  4. Development and testing of a diagnostic system for intelligen distributed control at EBR-2

    International Nuclear Information System (INIS)

    Edwards, R.M.; Ruhl, D.W.; Klevans, E.H.; Robinson, G.E.

    1990-01-01

    A diagnostic system is under development for demonstration of Intelligent Distributed Control at the Experimental Breeder Reactor (EBR--II). In the first phase of the project a diagnostic system is being developed for the EBR-II steam plant based on the DISYS expert systems approach. Current testing uses recorded plant data and data from simulated plant faults. The dynamical simulation of the EBR-II steam plant uses the Babcock and Wilcox (B ampersand W) Modular Modeling System (MMS). At EBR-II the diagnostic system operates in the UNIX workstation and receives live plant data from the plant Data Acquisition System (DAS). Future work will seek implementation of the steam plant diagnostic in a distributed manner using UNIX based computers and Bailey microprocessor-based control system. 10 refs., 6 figs

  5. Point of Care Tuberculosis Sero-Diagnosis Kit for Wild Animals: Combination of Proteins for Improving the Diagnostic Sensitivity and Specificity.

    Science.gov (United States)

    Veerasami, Maroudam; Venkataraman, K; Karuppannan, Chitra; Shanmugam, Arun Attur; Prudhvi, Mallepaddi Chand; Holder, Thomas; Rathnagiri, Polavarapu; Arunmozhivarman, K; Raj, Gopal Dhinakar; Vordermeier, Martin; Mohana Subramanian, B

    2018-03-01

    Tuberculosis is a significant problem globally for domestic animals as well as captive and free ranging wild life. Rapid point of care (POC) serology kits are well suited for the diagnosis of TB in wild animals. However, wild animals are invariably exposed to environmental non-pathogenic mycobacterium species with the development of cross reacting antibodies. In the present study, POC TB diagnosis kit was developed using a combination of pathogenic Mycobacteria specific recombinant antigens and purified protein derivatives of pathogenic and non-pathogenic Mycobacteria . To benchmark the TB antibody detection kit, particularly in respect to specificity which could not be determined in wildlife due to the lack of samples from confirmed uninfected animals, we first tested well-characterized sera from 100 M. bovis infected and 100 uninfected cattle. Then we investigated the kit's performance using sera samples from wildlife, namely Sloth Bears (n = 74), Elephants (n = 9), Cervidae (n = 14), Felidae (n = 21), Cape buffalo (n = 2), Wild bear (n = 1) and Wild dog (n = 1).In cattle, a sensitivity of 81% and a specificity of 90% were obtained. The diagnostic sensitivity of the kit was 94% when the kit was tested using known TB positive sloth bear sera samples. 47.4% of the in-contact sloth bears turned seropositive using the rapid POC TB diagnostic kit. Seropositivity in other wild animals was 25% when the sera samples were tested using the kit. A point of care TB sero-diagnostic kit with the combination of proteins was developed and the kit was validated using the sera samples of wild animals.

  6. A web-based test of residents' skills in diagnostic radiology

    International Nuclear Information System (INIS)

    Finlay, K.; Norman, G.R.; Keane, D.R.; Stolberg, H.

    2006-01-01

    To develop an objective, Web-based tool for evaluating residents' knowledge of diagnostic radiology. We developed and tested a Web-based evaluation tool (the Diagnostic Radiology Skills Test) that consists of 3 tests, one in each of 3 domains of diagnostic radiology: chest, gastrointestinal, and musculoskeletal imaging. Each test comprises 30 cases representing a range of difficulty in the domain, including normal states, normal variants, typical cases of common diagnoses, and cases with more subtle findings. Cases are presented with a long menu of domain-specific possible diagnoses (response options), each coded for diagnostic appropriateness. Our subjects were 21 residents in postgraduate year (PGY) 2 to 5 and 11 experts in diagnostic radiology. Subjects accessed the tool via a Web site on our Web server. Residents test results were compared for reliability and validity across domain, case, and training level. In addition, results were correlated with commonly used established and objective evaluation tools. The tool demonstrated consistent monotonic improvement in performance with training level. It showed acceptable reliability in discriminating between residents at different performance levels, both within and across training levels (r = 0.53 within level and 0.69 across levels). Test results also had concurrent validity against the American College of Radiology In-Training Examination, a widely accepted objective assessment tool (r = 0.65, P < 0.01), and 2 Objective Structured Clinical Examinations (OSCEs) focusing on diagnostic skills (r = 0.78 and r 0.69, P < 0.01, respectively). Our study demonstrates the feasibility of a Web-based, standardized, objective assessment method for evaluating residents' performance. (author)

  7. Diagnostic Role of Head-Bending and Lying-Down Tests in Lateral Canal Benign Paroxysmal Positional Vertigo.

    Science.gov (United States)

    Yetiser, Sertac; Ince, Dilay

    2015-08-01

    To compare the diagnostic value of the head-bending test (HBT), lying-down positioning test (LDPT) and patient's report to identify the affected canal in video-nystagmographically (VNG) confirmed patients with lateral canal benign paroxysmal positional vertigo (LC-BPPV). Case series with chart review. Head-bending, lying-down positioning and the head-roll maneuver (HRM) under VNG guidance. The data were collected in a referral community hospital. Seventy-eight patients (32 apogeotropic and 46 geotropic nystagmus) with LC-BPPV who had been recruited between 2009 and 2013 were enrolled in the study. Patients were tested with the HRM and then were asked about subjectively worse side. Later, they were subjected to HBT when sitting and the LDPT. The results were compared and studied with the 1-way ANOVA and chi-square tests. Statistical significance was set at p < 0.05. Affected side was identified by HRM in 75% of patients with apogeotropic nystagmus and 95.6% of patients with geotropic nystagmus. Approximately 65.6% of patients with apogeotropic and 52% of patients with geotropic nystagmus had nystagmus during LDPT. However, its comparability with HRM was low. However, treatment plan based on LDPT results alone provided relief of symptoms in additional 12.5% of patients with apogeotropic and in 2.2% of patients with geotropic nystagmus. Approximately 63% of patients with apogeotropic and 56% of patients with geotropic nystagmus were able to tell the worse side. Nystagmus comparable with HRM during HBT was low and not diagnostic. HRM has the greatest diagnostic value of positioning tests in LC-BPPV in this study. LDPT provides some contribution in the diagnosis of LC-BPPV but much less than HRM. Patients' subjective feeling of vertigo was also a useful test. However, HBT was not as sensitive as other measures in uncertain cases.

  8. Minimal residual disease diagnostics in acute lymphoblastic leukemia: Need for sensitive, fast, and standardized technologies

    NARCIS (Netherlands)

    J.J.M. van Dongen (Jacques); V.H.J. van der Velden (Vincent); M. Brüggemann (Monika); A. Orfao (Alberto)

    2015-01-01

    textabstractMonitoring of minimal residual disease (MRD) has become routine clinical practice in frontline treatment of virtually all childhood acute lymphoblastic leukemia (ALL) and in many adult ALL patients. MRD diagnostics has proven to be the strongest prognostic factor, allowing for risk group

  9. Clinical Utility of Diagnostic Laboratory Tests in Dogs with Acute Pancreatitis: A Retrospective Investigation in a Primary Care Hospital.

    Science.gov (United States)

    Yuki, M; Hirano, T; Nagata, N; Kitano, S; Imataka, K; Tawada, R; Shimada, R; Ogawa, M

    2016-01-01

    Acute pancreatitis (AP) occurs frequently in dogs, but most previous studies examining the diagnosis of AP have used data from secondary care hospitals. The aim of this study was to investigate the clinical utility of diagnostic laboratory tests in dogs with AP in a primary care hospital. Sixty-four dogs with clinical signs suggestive of AP diagnosed with nonpancreatic disease (NP) or AP. Medical records were retrospectively reviewed, including diagnostic laboratory tests considered potentially useful in the diagnosis of AP. The diagnostic accuracy of amylase and FUJI DRI-CHEM lipase (FDC lip) were investigated using receiver operating characteristics (ROC). In addition, we verified whether diagnostic laboratory tests were useful for evaluating duration of hospitalization and as biomarkers for monitoring recovery. Activities of amylase and FDC lip were significantly higher in the AP group than in the NP group (P = .001, P < .001, respectively). The sensitivity of FDP lip activity for diagnosing AP was 100% (95% confidence interval [CI], 87.7-100%); the specificity was 89.5% (95% CI, 66.9-98.7%). Area under the ROC curve for FDC lip activity was 0.98 (95% CI, 0.93-1). High alanine aminotransferase (ALT) activity was associated with extended duration of hospitalization (P = .04). A significant difference in C-reactive protein (CRP) concentration before and 5 days after treatment was found (P = .001). Measurement of FDC lip activity appears useful for diagnosing AP. High ALT activity might be associated with prolonged duration of hospitalization, and CRP might be useful as a biomarker for monitoring recovery from AP. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  10. Diagnostic accuracy and acceptability of rapid HIV oral testing among adults attending an urban public health facility in Kampala, Uganda.

    Directory of Open Access Journals (Sweden)

    Joanita Nangendo

    Full Text Available The prevalence of HIV in Uganda is 7.3%, and yet nearly 40% of people living with HIV are unaware of their status. The current HIV testing policy which is strictly blood-based poses several challenges including: a need for high level laboratory skills, stringent waste disposal needs, and painful sample collection. It is envisaged that introduction of a rapid, painless HIV oral fluid test as a potential alternative is likely to increase the number of people testing. The aim of this study was to determine the diagnostic accuracy and acceptability of rapid HIV oral testing among adults attending Kisenyi Health Centre IV in Kampala.We conducted a cross-sectional study among 440 adults recruited consecutively at Kisenyi Health Centre IV from January to March 2016. The diagnostic accuracy of the HIV oral test was assessed by comparing to the national HIV serial testing algorithm. We also assessed for acceptability among patients and health care workers (HCWs by triangulating responses from a structured questionnaire, three focus group discussions and seven key informant interviews. Acceptability was defined as willingness to take the test at the time of the study and intention for future use of the test if it was availed. The prevalence of HIV infection among study participants was 14.8%. The HIV oral fluid test was highly accurate with sensitivity of 100% (95% CI; 94.5-100.0, specificity of 100% (95% CI; 99.0-100.0, positive predictive value (PPV of 100% (95% CI; 94.5-100.0 and negative predictive value (NPV of 100% (95% CI; 99.0-100.0. Acceptability of HIV oral testing was also high at 87.0% (95% CI; 83.6-89.9. Participants preferred HIV oral testing because it was: pain free (91%, n = 399 and did not require blood draw (82%, n = 360.The HIV oral fluid test has high diagnostic accuracy and acceptability. HIV oral testing is a suitable addition to the national HIV testing strategies with the potential of increasing access to HIV testing services in

  11. Overview of NASA GRCs Green Propellant Infusion Mission Thruster Testing and Plume Diagnostics

    Science.gov (United States)

    Deans, Matthew C.; Reed, Brian D.; Yim, John T.; Arrington, Lynn A.; Williams, George J.; Kojima, Jun J.; McLean, Christopher H.

    2014-01-01

    The Green Propellant Infusion Mission (GPIM) is sponsored by NASA's Space Technology Mission Directorate (STMD) Technology Demonstration Mission (TDM) office. The goal of GPIM is to advance the technology readiness level of a green propulsion system, specifically, one using the monopropellant, AF-M315E, by demonstrating ground handling, spacecraft processing, and on-orbit operations. One of the risks identified for GPIM is potential contamination of sensitive spacecraft surfaces from the effluents in the plumes of AF-M315E thrusters. NASA Glenn Research Center (GRC) is conducting activities to characterize the effects of AF-M315E plume impingement and deposition. GRC has established individual plume models of the 22-N and 1-N thrusters that will be used on the GPIM spacecraft. The models describe the pressure, temperature, density, Mach number, and species concentration of the AF-M315E thruster exhaust plumes. The models are being used to assess the impingement effects of the AF-M315E thrusters on the GPIM spacecraft. The model simulations will be correlated with plume measurement data from Laboratory and Engineering Model 22-N, AF-M315E thrusters. The thrusters will be tested in a small rocket, altitude facility at NASA GRC. The GRC thruster testing will be conducted at duty cycles representatives of the planned GPIM maneuvers. A suite of laser-based diagnostics, including Raman spectroscopy, Rayleigh spectroscopy, Schlieren imaging, and physical probes will be used to acquire plume measurements of AFM315E thrusters. Plume data will include temperature, velocity, relative density, and species concentration. The plume measurement data will be compared to the corresponding simulations of the plume model. The GRC effort will establish a data set of AF-M315E plume measurements and a plume model that can be used for future AF-M315E applications.

  12. A novel technique for detecting antibiotic-resistant typhoid from rapid diagnostic tests.

    Science.gov (United States)

    Nic Fhogartaigh, Caoimhe; Dance, David A B; Davong, Viengmon; Tann, Pisey; Phetsouvanh, Rattanaphone; Turner, Paul; Dittrich, Sabine; Newton, Paul N

    2015-05-01

    Fluoroquinolone-resistant typhoid is increasing. An antigen-detecting rapid diagnostic test (RDT) can rapidly diagnose typhoid from blood cultures. A simple, inexpensive molecular technique performed with DNA from positive RDTs accurately identified gyrA mutations consistent with phenotypic susceptibility testing results. Field diagnosis combined with centralized molecular resistance testing could improve typhoid management and surveillance in low-resource settings. Copyright © 2015, Nic Fhogartaigh et al.

  13. The basophil activation test: a sensitive test in the diagnosis of allergic immediate hypersensitivity to pristinamycin.

    Science.gov (United States)

    Viel, Sébastien; Garnier, Lorna; Joly, Elodie; Rouzaire, Paul; Nosbaum, Audrey; Pralong, Pauline; Faudel, Amélie; Rioufol, Catherine; Bienvenu, Françoise; Bienvenu, Jacques; Berard, Frédéric

    2015-01-01

    Immediate hypersensitivity (IHS) reactions to macrolides and to macrolide-derived antibiotics like pristinamycin are uncommon. In this context, there is little data available to appreciate the true value of biological tools regarding the diagnosis of immediate allergy to pristinamycin. Here we assess the clinical usefulness of the basophil activation test (BAT) to differentiate allergic from nonallergic IHS to pristinamycin. Thirty-six patients were tested with skin tests as the gold standard and BAT. The BAT achieved a sensitivity of 76% and a specificity of 100%, implying an absence of false positive results. Multicenter studies remain to be performed to better define the sensitivity, specificity and interlaboratory variation of BAT in the diagnosis of allergy to pristinamycin and macrolides. © 2015 S. Karger AG, Basel.

  14. Sensitivity study on hydraulic well testing inversion using simulated annealing

    Energy Technology Data Exchange (ETDEWEB)

    Nakao, Shinsuke; Najita, J.; Karasaki, Kenzi

    1997-11-01

    For environmental remediation, management of nuclear waste disposal, or geothermal reservoir engineering, it is very important to evaluate the permeabilities, spacing, and sizes of the subsurface fractures which control ground water flow. Cluster variable aperture (CVA) simulated annealing has been used as an inversion technique to construct fluid flow models of fractured formations based on transient pressure data from hydraulic tests. A two-dimensional fracture network system is represented as a filled regular lattice of fracture elements. The algorithm iteratively changes an aperture of cluster of fracture elements, which are chosen randomly from a list of discrete apertures, to improve the match to observed pressure transients. The size of the clusters is held constant throughout the iterations. Sensitivity studies using simple fracture models with eight wells show that, in general, it is necessary to conduct interference tests using at least three different wells as pumping well in order to reconstruct the fracture network with a transmissivity contrast of one order of magnitude, particularly when the cluster size is not known a priori. Because hydraulic inversion is inherently non-unique, it is important to utilize additional information. The authors investigated the relationship between the scale of heterogeneity and the optimum cluster size (and its shape) to enhance the reliability and convergence of the inversion. It appears that the cluster size corresponding to about 20--40 % of the practical range of the spatial correlation is optimal. Inversion results of the Raymond test site data are also presented and the practical range of spatial correlation is evaluated to be about 5--10 m from the optimal cluster size in the inversion.

  15. No gold standard estimation of the sensitivity and specificity of two molecular diagnostic protocols for Trypanosoma brucei spp. in Western Kenya.

    Directory of Open Access Journals (Sweden)

    Barend Mark de Clare Bronsvoort

    2010-01-01

    Full Text Available African animal trypanosomiasis is caused by a range of tsetse transmitted protozoan parasites includingTrypanosoma vivax, Trypanosoma congolense and Trypansoma brucei. In Western Kenya and other parts of East Africa two subspecies of T. brucei, T.b. brucei and the zoonoticT.b. rhodesiense, co-circulate in livestock. A range of polymerase chain reactions (PCR have been developed as important molecular diagnostic tools for epidemiological investigations of T. brucei s.l. in the animal reservoir and of its zoonotic potential. Quantification of the relative performance of different diagnostic PCRs is essential to ensure comparability of studies. This paper describes an evaluation of two diagnostic test systems for T. brucei using a T. brucei s.l. specific PCR [1] and a single nested PCR targeting the Internal Transcribed Spacer (ITS regions of trypanosome ribosomal DNA [2]. A Bayesian formulation of the Hui-Walter latent class model was employed to estimate their test performance in the absence of a gold standard test for detecting T.brucei s.l. infections in ear-vein blood samples from cattle, pig, sheep and goat populations in Western Kenya, stored on Whatman FTA cards. The results indicate that the system employing the T. brucei s.l. specific PCR (Se1=0.760 had a higher sensitivity than the ITS-PCR (Se2=0.640; both have high specificity (Sp1=0.998; Sp2=0.997. The true prevalences for livestock populations were estimated (pcattle=0.091, ppigs=0.066, pgoats=0.005, psheep=0.006, taking into account the uncertainties in the specificity and sensitivity of the two test systems. Implications of test performance include the required survey sample size; due to its higher sensitivity and specificity, the T. brucei s.l. specific PCR requires a consistently smaller sample size than the ITS-PCR for the detection of T. brucei s.l. However the ITS-PCR is able to simultaneously screen samples for other pathogenic trypanosomes and may thus be, overall, a better

  16. Towards Modernizing the Characterization of Shock and Detonation Physics Performance via Novel Diagnostics and Tests

    Science.gov (United States)

    Salyer, Terry

    2017-06-01

    For the bulk of detonation performance experiments, a fairly basic set of diagnostic techniques has evolved as the standard for acquiring the necessary measurements. Gold standard techniques such as pin switches and streak cameras still produce the high-quality data required, yet much room remains for improvement with regard to ease of use, cost of fielding, breadth of data, and diagnostic versatility. Over the past several years, an alternate set of diagnostics has been under development to replace many of these traditional techniques. Pulse Correlation Reflectometry (PCR) is a capable substitute for pin switches with the advantage of obtaining orders of magnitude more data at a small fraction of the cost and fielding time. Spectrally Encoded Imaging (SEI) can replace most applications of streak camera with the advantage of imaging surfaces through a single optical fiber that are otherwise optically inaccessible. Such diagnostics advance the measurement state of the art, but even further improvements may come through revamping the standardized tests themselves such as the copper cylinder expansion test. At the core of this modernization, the aforementioned diagnostics play a significant role in revamping and improving the standard test suite for the present era. This research was performed under the auspices of the United States Department of Energy.

  17. Diagnostic performances of two rapid tests for detection of feline leukemia virus antigen in sera of experimentally feline leukemia virus-infected cats

    Directory of Open Access Journals (Sweden)

    Matthew R Krecic

    2017-12-01

    Full Text Available Objectives The objective of this study was to compare the diagnostic sensitivities and specificities of WITNESS FeLV-FIV (Zoetis and SNAP FIV/FeLV Combo Test (IDEXX for the detection of FeLV p27 antigen in the sera of experimentally feline leukemia virus (FeLV-infected cats. Methods Diagnostic sensitivities of WITNESS and SNAP were determined through testing of 47 serum samples collected from cats day 56 post-experimental infection with a virulent FeLV Rickard strain. Successful experimental infection was confirmed based on observation of FeLV antigen and proviral DNA in anti-coagulated (EDTA whole-blood samples by immunofluorescent antibody (IFA test and PCR, respectively. Diagnostic specificities of both tests were determined through testing of sera of 92 laboratory-housed, non-FeLV-exposed specific pathogen-free (SPF cats. Results Forty-one of 47 blood samples were IFA positive, whereas all 47 samples were PCR positive. All 92 non-FeLV-infected SPF cats were IFA and PCR negative. In comparison to IFA as the reference method, both WITNESS and SNAP tests yielded equivalent sensitivities and specificities of 100% and 97.8%, respectively. In comparison to PCR as the reference method, both WITNESS and SNAP tests likewise performed equivalently, with sensitivities and specificities of 91.5% and 100%, respectively. Conclusions and relevance Sensitivity and specificity of WITNESS FeLV-FIV for identifying FeLV p27 antigen in the sera of these experimentally FeLV-infected and non-FeLV-exposed SPF cats equaled those of the SNAP FIV/FeLV Combo Test. However, all positive results, regardless of the point-of-care test used, should be confirmed before making clinical decisions such as segregation from other cats or euthanasia.

  18. Comparative field performance and adherence to test results of four malaria rapid diagnostic tests among febrile patients more than five years of age in Blantyre, Malawi

    Directory of Open Access Journals (Sweden)

    San Joaquin Miguel

    2010-07-01

    Full Text Available Abstract Background Malaria rapid diagnostics tests (RDTs can increase availability of laboratory-based diagnosis and improve the overall management of febrile patients in malaria endemic areas. In preparation to scale-up RDTs in health facilities in Malawi, an evaluation of four RDTs to help guide national-level decision-making was conducted. Methods A cross sectional study of four histidine rich-protein-type-2- (HRP2 based RDTs at four health centres in Blantyre, Malawi, was undertaken to evaluate the sensitivity and specificity of RDTs, assess prescriber adherence to RDT test results and explore operational issues regarding RDT implementation. Three RDTs were evaluated in only one health centre each and one RDT was evaluated in two health centres. Light microscopy in a reference laboratory was used as the gold standard. Results A total of 2,576 patients were included in the analysis. All of the RDTs tested had relatively high sensitivity for detecting any parasitaemia [Bioline SD (97%, First response malaria (92%, Paracheck (91%, ICT diagnostics (90%], but low specificity [Bioline SD (39%, First response malaria (42%, Paracheck (68%, ICT diagnostics (54%]. Specificity was significantly lower in patients who self-treated with an anti-malarial in the previous two weeks (odds ratio (OR 0.5; p-value 15 years old (OR 0.4, p-value Conclusions The results of this evaluation, combined with other published data and global recommendations, have been used to select RDTs for national scale-up. In addition, the study identified some key issues that need to be further delineated: the low field specificity of RDTs, variable RDT performance by different cadres of health workers and the need for a robust quality assurance system. Close monitoring of RDT scale-up will be needed to ensure that RDTs truly improve malaria case management.

  19. Diagnostic Accuracy of PIK3CA Mutation Detection by Circulating Free DNA in Breast Cancer: A Meta-Analysis of Diagnostic Test Accuracy.

    Science.gov (United States)

    Zhou, Yidong; Wang, Changjun; Zhu, Hanjiang; Lin, Yan; Pan, Bo; Zhang, Xiaohui; Huang, Xin; Xu, Qianqian; Xu, Yali; Sun, Qiang

    2016-01-01

    Mutation of p110 alpha-catalytic subunit of phosphatidylinositol 3-kinase (PIK3CA) has high predictive and prognostic values for breast cancer. Hence, there has been a marked interest in detecting and monitoring PIK3CA genotype with non-invasive technique, such as circulating free DNA (cfDNA). However, the diagnostic accuracy of PIK3CA genotyping by cfDNA is still a problem of controversy. Here, we conducted the first meta-analysis to evaluate overall diagnostic performance of cfDNA for PIK3CA mutation detection. Literature search was performed in Pubmed, Embase and Cochrane Central Register of Controlled Trials databases. Seven cohorts from five studies with 247 patients were included. The pooled sensitivity, specificity, positive and negative likelihood ratio, diagnostic odds ratio and area under summary receiver operating characteristic curve were calculated for accuracy evaluation. The pooled sensitivity and specificity were 0.86 (95% confidence interval [CI] 0.32-0.99) and 0.98 (95% CI 0.86-1.00), respectively; the pooled positive and negative likelihood ratio were 42.8 (95% CI 5.1-356.9) and 0.14 (95% CI 0.02-1.34), respectively; diagnostic odds ratio for evaluating the overall diagnostic performance was 300 (95% CI 8-11867); area under summary receiver operating characteristic curve reached 0.99 (95% CI 0.97-0.99). Subgroup analysis with metastatic breast cancer revealed remarkable improvement in diagnostic performance (sensitivity: 0.86-0.91; specificity: 0.98; diagnostic odds ratio: 300-428). This meta-analysis proved that detecting PIK3CA gene mutation by cfDNA has high diagnostic accuracy in breast cancer, especially for metastatic breast cancer. It may serve as a reliable non-invasive assay for detecting and monitoring PIK3CA mutation status in order to deliver personalized and precise treatment.

  20. Appraising and applying evidence about a diagnostic test during a performance-based assessment

    Directory of Open Access Journals (Sweden)

    Franklin Ellen

    2004-10-01

    Full Text Available Abstract Background The practice of Evidence-based Medicine requires that clinicians assess the validity of published research and then apply the results to patient care. We wanted to assess whether our soon-to-graduate medical students could appraise and apply research about a diagnostic test within a clinical context and to compare our students with peers trained at other institutions. Methods 4th year medical students who previously had demonstrated competency at probability revision and just starting first-year Internal Medicine residents were used for this research. Following an encounter with a simulated patient, subjects critically appraised a paper about an applicable diagnostic test and revised the patient's pretest probability given the test result. Results The medical students and residents demonstrated similar skills at critical appraisal, correctly answering 4.7 and 4.9, respectively, of 6 questions (p = 0.67. Only one out of 28 (3% medical students and none of the 15 residents were able to correctly complete the probability revision task (p = 1.00. Conclusions This study found that most students completing medical school are able to appraise an article about a diagnostic test but few are able to apply the information from the article to a patient. These findings raise questions about the clinical usefulness of the EBM skills possessed by graduating medical students within the area of diagnostic testing.

  1. Design of the background gas pressure diagnostic for the Mirror Fusion Test Facility

    International Nuclear Information System (INIS)

    Thomas, S.R.; Stever, R.D.; Goerz, D.A.; Pickles, W.L.

    1985-01-01

    The Background Gas Pressure (BGP) diagnostic is a collection of pressure gauges inside the Mirror Fusion Test Facility (MFTF-B) vacuum vessel to measure neutral gas density near the plasma region. These measurements will help us understand the role of background neutrals in particle and power balance, particularly in the maintenance of the cold halo plasma that shields the hot core plasma from returning neutrals. The diagnostic consists of magnetron-type, cold-cathode gauges, each stripped of its permanent magnet, and utilizing the MFTF-B ambient B-field in strengths of 1 to 25 kG. As part of the design effort, tests were performed to characterize gauge operation in strong magnetic field strengths and to evaluate the parameters affecting performance. This paper describes the BGP diagnostic and presents the details of the mechanical and electrical design

  2. Comparison of approaches to estimate confidence intervals of post-test probabilities of diagnostic test results in a nested case-control study

    Directory of Open Access Journals (Sweden)

    van Zaane Bas

    2012-10-01

    Full Text Available Abstract Background Nested case–control studies become increasingly popular as they can be very efficient for quantifying the diagnostic accuracy of costly or invasive tests or (biomarkers. However, they do not allow for direct estimation of the test’s predictive values or post-test probabilities, let alone for their confidence intervals (CIs. Correct estimates of the predictive values itself can easily be obtained using a simple correction by the (inverse sampling fractions of the cases and controls. But using this correction to estimate the corresponding standard error (SE, falsely increases the number of patients that are actually studied, yielding too small CIs. We compared different approaches for estimating the SE and thus CI of predictive values or post-test probabilities of diagnostic test results in a nested case–control study. Methods We created datasets based on a large, previously published diagnostic study on 2 different tests (D-dimer test and calf difference