scholarly journals Evaluation of 2-column agglutination versus conventional tube technique for antibody screening

2021 ◽  
Vol 9 (3) ◽  
pp. 407-412
Author(s):  
A. Abou Jabal ◽  
T. Shubeilat ◽  
F. Hajjiri
Keyword(s):  
Serum Samples ◽  
Antibody Screening ◽  
Negative Results ◽  
Specificity And Sensitivity ◽  
Low Concentrations ◽  
Indirect Antiglobulin Test ◽  
Antiglobulin Test ◽  
Screening And Identification ◽  
Clinically Significant ◽  
Positive Results

The study aimed to determine the specificity and sensitivity of the Ortho BioVue two-column agglutination system for the detection of low concentrations of clinically significant antibodies in serum. The BioVue system was compared with the conventional tube technique [LISS-Coombs indirect antiglobulin test], and the two-stage Papenzyme test was used to resolve discrepancies between the two methods. We tested 3000 serum samples from randomly selected patients at King Hussein Medical Centre. Both the antibody screening and identification gave negative results in 2952 patients and positive results in 48 patients. We found the BioVue system to be the more sensitive technique. However, if papain enzyme-treated cells were included in the conventional tube technique when applied to antibody screening and identification, both methods would be of comparable sensitivity

scholarly journals Excretion and Detection of Cathinone, Cathine, and Phenylpropanolamine in Urine after Kath Chewing

2002 ◽  
Vol 48 (10) ◽  
pp. 1715-1719 ◽  
Author(s):  
Stefan W Toennes ◽  
Gerold F Kauert
Keyword(s):  
Analytical Techniques ◽  
Urine Samples ◽  
Gas Chromatography Mass Spectrometry ◽  
Fluorescence Polarization Immunoassay ◽  
Photodiode Array Detection ◽  
Negative Results ◽  
Specificity And Sensitivity ◽  
Photodiode Array ◽  
Array Detection ◽  
Positive Results

Abstract Introduction: The stimulating herbal drug kath is uncommon in most countries, and information on its detection and interpretation of analytical results is limited. Therefore, a study with kath was carried out to compare the efficiencies of different analytical techniques used to detect drug use. Methods: Four volunteers chewed kath leaves for 1 h; urine samples were collected up to 80 h afterward and analyzed by the Abbott fluorescence polarization immunoassay (FPIA), the Mahsan-AMP300 on-site immunoassay, the Bio-Rad Remedi HS HPLC system with photodiode array detection (DAD), and gas chromatography–mass spectrometry (GC-MS). Results: FPIA gave negative results, whereas positive results were obtained with the Mahsan test during the first day. With HPLC, one peak could be observed up to 50 h, but its DAD spectrum could not be identified by the system. Further investigations indicated that the kath alkaloids coeluted and produced a mixed DAD spectrum. With GC-MS, the specific kath ingredient cathinone was detected up to 26 h, whereas cathine and norephedrine were still detectable in the last samples. Maximum concentrations of cathinone, cathine, and norephedrine in urine samples from the study were 2.5, 20, and 30 mg/L, respectively, whereas in authentic cases the concentrations were much higher. Conclusion: GC-MS is superior to the screening techniques Mahsan-AMP300 and Remedi with respect to specificity and sensitivity for the detection of kath use in urine.

scholarly journals Potential Impact of Different Cytomegalovirus (CMV) IgM Assays on an Algorithm Requiring IgM Reactivity as a Criterion for Measuring CMV IgG Avidity

2014 ◽  
Vol 21 (6) ◽  
pp. 813-816 ◽  
Author(s):  
Harry E. Prince ◽  
Mary Lapé-Nixon ◽  
Andrew Brenner ◽  
Nancy Pitstick ◽  
Marc Roger Couturier
Keyword(s):  
Cmv Infection ◽  
Serum Samples ◽  
Immunofluorescent Assay ◽  
Negative Results ◽  
Igg Avidity ◽  
Positive Serum ◽  
Chemiluminescent Immunoassay ◽  
Potential Impact ◽  
The Impact ◽  
Positive Results

ABSTRACTThe measurement of cytomegalovirus (CMV) IgG avidity is a powerful tool for identifying individuals with recent CMV infection. Because such patients are expected to be positive for CMV IgM, several investigators have suggested that CMV IgG-positive sera first be screened for CMV IgM and then only the IgM-reactive sera be tested for avidity. We investigated the impact of different CMV IgM assays on such a reflexing algorithm using a panel of 369 consecutive IgG-positive serum samples submitted for avidity testing. A bead-based immunofluorescent assay (BIFA) identified 105 IgM-positive serum samples, whereas an IgM-capture enzyme immunoassay (EIA) identified 48 IgM-positive serum samples; this marked difference led us to evaluate additional CMV IgM assays. An enzyme-linked immunofluorescent assay (ELFA) and a chemiluminescent immunoassay (CIA) were used to test all sera with discordant BIFA/EIA results, all sera with concordant positive results, and selected sera with concordant negative results. The findings indicated that the ELFA would identify 74 CMV IgM-positive samples and the CIA would identify 64. Of the 23 low-avidity serum samples, 2 were IgM negative by BIFA, 3 by ELFA and CIA, and 4 by EIA; of the 23 intermediate-avidity serum samples, 6 were IgM negative by BIFA, 10 by ELFA, and 15 by EIA and CIA. In both these avidity groups, BIFA IgM-negative sera were also negative by the other 3 assays. These findings demonstrate that an algorithm requiring CMV IgM reactivity as a criterion for CMV IgG avidity testing does not identify all low-avidity sera and thus misses some cases of acute CMV infection.

scholarly journals Frequencies and Specificities of “Enzyme-Only” Detected Erythrocyte Alloantibodies in Patients Hospitalized in Austria: Is an Enzyme Test Required for Routine Red Blood Cell Antibody Screening?

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Dietmar Enko ◽  
Claudia Habres ◽  
Franz Wallner ◽  
Barbara Mayr ◽  
Gabriele Halwachs-Baumann
Keyword(s):  
Blood Cell ◽  
Red Blood Cell ◽  
Blood Samples ◽  
Antibody Screening ◽  
Indirect Antiglobulin Test ◽  
Cell Antibody ◽  
Antiglobulin Test ◽  
Low Ionic Strength ◽  
Enzyme Test ◽  
Screening Result

The aim of this study was to determine the frequencies and specificities of “enzyme-only” detected red blood cell (RBC) alloantibodies in the routine antibody screening and antibody identification in patients hospitalized in Austria. Routine blood samples of 2420 patients were investigated. The antibody screening was performed with a 3-cell panel in the low-ionic strength saline- (LISS-) indirect antiglobulin test (IAT) and with an enzyme-pretreated (papain) 3-cell panel fully automated on the ORTHO AutoVue Innova System. The antibody identification was carried out manually with an 11-cell panel in the LISS-IAT and with an enzyme-pretreated (papain) 11-cell panel. In total 4.05% (n=98) of all patients (n=2420) had a positive RBC antibody screening result. Of them 25.51% (25/98) showed “enzyme-only” detected specific or nonspecific RBC alloantibodies. Rhesus and Lewis system antibodies were found the only specificities of “enzyme-only” RBC alloantibodies: all in all 4.8% (4/98) were detected with anti-E, 3.06% (3/98) with anti-Lea, 3.06% (3/98) with anti-D after anti-D prophylaxis and 1.02% (1/98) with anti-e. In total, 14.29% (14/98) showed a nonspecific RBC alloantibody result with the enzyme test. The results of the present study demonstrate that a high number of unwanted positive reactions with the enzyme technique overshadows the detection of “enzyme-only” RBC alloantibodies. (Trial Registration: K-37-13).

scholarly journals Usefulness of real-time PCR assay targeting lipL32 gene for diagnosis of human leptospirosis in Uruguay

2013 ◽  
Vol 7 (12) ◽  
pp. 941-945 ◽  
Author(s):  
Sabina González ◽  
Juan Pablo Geymonat ◽  
Elba Hernández ◽  
Juan Martín Marqués ◽  
Felipe Schelotto ◽  
...  
Keyword(s):  
Real Time ◽  
Real Time Pcr ◽  
Dna Amplification ◽  
Diagnostic Sensitivity ◽  
Analytical Sensitivity ◽  
Serum Samples ◽  
Initial Management ◽  
Negative Results ◽  
Acute Infections ◽  
Positive Results

Introduction: Assays based on DNA amplification can provide information that contributes to the initial management of patients with leptospirosis. However, these have not been adopted in Uruguay. Our aim was to evaluate the performance of the lipL32 real-time PCR (qPCR) for diagnosis of leptospirosis. Methodology: We analyzed by microscopic agglutination test (MAT) and lipL32 qPCR serum samples from 183 patients with suspected leptospirosis. To establish the analytical sensitivity of the qPCR, experimentally spiked samples with known amounts of Leptospira interrogans were analyzed. Results: The analytical sensitivity of the qPCR was 102 leptospires/mL. In 98 patients MAT results were negative meanwhile 85 showed positive reactions, revealing acute infections. Twenty six acute-phase sera of these 85 patients showed a positive signal by qPCR (diagnostic sensitivity 30%). In these patients the average time between onset of symptoms and collection of the first sample was 8 days. In patients with negative results for qPCR and positive MAT results (n=59) the average interval between onset of symptoms and collection of the first sample was 13 days. The qPCR did not yield false positive results. Conclusions: The qPCR had a lower diagnostic sensitivity than MAT and a higher cost. However, it allowed to make an early diagnosis in 26 patients. In patients with confirmed acute infections and negative results by qPCR, more than 8 days had elapsed between the onset of the illness and extraction of the first serum sample. Our data support that the qPCR from sera have clinical utility within the first week of illness.

scholarly journals The Reliability of a Novel Automated System for ANA Immunofluorescence Analysis in Daily Clinical Practice

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Mohammed Alsuwaidi ◽  
Margit Dollinger ◽  
Martin Fleck ◽  
Boris Ehrenstein
Keyword(s):  
Clinical Practice ◽  
Clinical Care ◽  
Daily Clinical Practice ◽  
Automated System ◽  
Visual Interpretation ◽  
Serum Samples ◽  
Negative Results ◽  
Automated Interpretation ◽  
Reading System ◽  
Positive Results

Automated interpretation (AI) systems for antinuclear antibody (ANA) analysis have been introduced based on assessment of indirect immunofluorescence (IIF) patterns. The diagnostic performance of a novel automated IIF reading system was compared with visual interpretation (VI) of IIF in daily clinical practice to evaluate the reduction of workload. ANA-IIF tests of consecutive serum samples from patients with suspected connective tissue disease were carried out using HEp-2 cells according to routine clinical care. AI was performed using a visual analyser (Zenit G-Sight, Menarini, Germany). Agreement rates between ANA results by AI and VI were calculated. Of the 336 samples investigated, VI yielded 205 (61%) negative, 42 (13%) ambiguous, and 89 (26%) positive results, whereas 82 (24%) were determined to be negative, 176 (52%) ambiguous, and 78 (24%) positive by AI. AI displayed a diagnostic accuracy of 175/336 samples (52%) with a kappa coefficient of 0.34 compared to VI being the gold standard. Solely relying on AI, with VI only performed for all ambiguous samples by AI, would have missed 1 of 89 (1%) positive results by VI and misclassified 2 of 205 (1%) negative results by VI as positive. The use of AI in daily clinical practice resulted only in a moderate reduction of the VI workload (82 of 336 samples: 24%).

scholarly journals Specificity and sensitivity as important parameters of the pattern of the homeopathic remedy

2021 ◽  
Vol 17 (2) ◽  
pp. 31-32
Author(s):  
Margarita Ashikhmina
Keyword(s):  
Sore Throat ◽  
Diagnostic Method ◽  
General Pattern ◽  
Correct Result ◽  
Source Information ◽  
Diagnostic Significance ◽  
Homeopathic Remedy ◽  
Negative Results ◽  
Specificity And Sensitivity ◽  
Positive Results

Aim: To assess the opportunity of use specificity (Sp) and sensitivity (Se) - indicators that are generally accepted for any diagnostic method - in homeopathy. Methodology: Analysis of comprehensions Specificity and Sensitivity in context of homeopathic knowledge. Results and discussions: In homeopathy, as in mathematics, patterns are identified through research, the main resources: provings, cases, repertory data, Materia Medica, and source information. S. Bohger wrote: “not all symptoms are equivalent”, “peculiar characteristics should be distinguished from the general series”. Considering the different facets in the general pattern of any remedy, we can see that the weight and diagnostic significance of each facet are different. Each facet of the pattern can be characterized by specificity (Sp) and sensitivity (Se) – indicators that are generally accepted for any diagnostic method. Specificity in medicine is the ability of the diagnostic method (facet of the pattern) not to give false positive results in the absence of disease (i.e., not to point to another remedy). Sp shows to what degree this parameter is typical for this remedy. It is defined as the proportion of the truly negative results of healthy individuals in the group under examination (i.e., the more often the facet is found in other remedies, the lower the specificity is). E.g., the Sp of sore throat for Hepar sulphur is how rarely the sore throat will be met in all other cases, except Hepar sulphur). Sensitivity is the ability of the diagnostic method (certain facet of the pattern) to give the correct result (to identify the remedy), which is defined as the proportion of true positive results among all tests performed (i.e., how often this facet of the pattern appears in this remedy compared to others). The Se reflects how often this pattern theme (symptom) occurs among all cases of this remedy, for example, how often we will find the sore throat among all cases of Hepar sulphur. The key symptoms, corresponding to the leading symptoms of the remedy, so-called “grains of gold” in homeopathy, can be attributed to highly specific parameters: they “valuable, few and hidden”, and as the “key to the lock” opening the whole case. Obviously, the key symptoms should have both high Sp and sufficient Se to be some kind of a visiting card of the remedy. Concomitant symptoms can be attributed to sensitive parameters, they complement the overall picture of the remedy, but they cannot be relied on in the decisive choice of the remedy (due to their low specificity). Conclusion: Sp and Se can use for description basic homeopathic terms and concepts and show diagnostic contribution of individual parameters in total pattern of the homeopathic remedy on different levels of disease.

scholarly journals Comparison of micro column technology with conventional tube methods for antibody detection

2017 ◽  
Vol 9 (02) ◽  
pp. 095-099 ◽  
Author(s):  
Sachin Garg ◽  
Nishant Saini ◽  
Ravneet Kaur Bedi ◽  
Sabita Basu
Keyword(s):  
Test Tube ◽  
Antibody Detection ◽  
Red Cell ◽  
Technological Advances ◽  
Indirect Antiglobulin Test ◽  
Antiglobulin Test ◽  
Column Technology ◽  
Clinically Significant ◽  
Low Ionic Strength ◽  
Cross Match

Abstract BACKGROUND AND OBJECTIVES: Conventional tube technique (CTT) has been the mainstay for antibody detection in pretransfusion testing. There have been rapid technological advances in blood banking and methodology of crossmatch has been modified to improve the sensitivity of these tests and to enable automation. This study was done to compare the efficacy of three crossmatch techniques: CTT, tube low-ionic-strength-saline indirect antiglobulin test (tube LISS-IAT), and micro column technology (MCT) used in the blood bank serology laboratory. MATERIALS AND METHODS: In this prospective study, 150 samples from patients who had received two or more transfusions on two different occasions (with at least 72 h between two transfusions) were subjected to cross match by three different techniques – CTT, LISS-IAT, and MCT. RESULTS: A total of 16 cases with antibodies were identified in 150 patients. Out of 16 cases, 14 were clinically significant (anti-c = 5, anti-K = 4, anti-E = 2, anti-S = 2, anti-Jka = 1) and 2 nonclinically significant antibody cases (anti-Lea). MCT detected all the 14 clinically significant antibody cases and no case of nonclinically significant antibody. Tube LISS-IAT detected 14 antibody cases including 2 cases of non-clinically significant antibody but failed to detect 1 case of anti-c and the only case of anti-Jka. CTT detected only 10 antibody cases including 2 cases of non-clinically significant antibody and but failed to detect 3 cases of anti-c, 1 case of anti-K, 1 case of anti-E, and the only case of anti-Jka. CONCLUSION: MCT was found to be most efficacious when compared to CTT and tube LISS-IAT in detecting clinically significant red cell antibodies; although MCT missed 2 cases of Lea antibody which were detected by CTT and LISS-IAT.

scholarly journals Effectiveness of Chest CT in Children: CT Findings in Relation to the Clinical Question

2021 ◽  
Author(s):  
Michael Esser ◽  
Ilias Tsiflikas ◽  
Mareen Sarah Kraus ◽  
Sabine Hess ◽  
Sergios Gatidis ◽  
...  
Keyword(s):  
Chest Ct ◽  
University Hospital ◽  
Cell Transplant ◽  
Clinical Question ◽  
Negative Results ◽  
Ct Findings ◽  
Pediatric Chest ◽  
Clinically Significant ◽  
Positive Results ◽  
Suspected Diagnosis

Purpose To estimate the effectiveness and efficiency of chest CT in children based on the suspected diagnosis in relation to the number of positive, negative, and inconclusive CT results. Materials and Methods In this monocentric retrospective study at a university hospital with a division of pediatric radiology, 2019 chest CT examinations (973 patients; median age: 10.5 years; range: 2 days to 17.9 years) were analyzed with regards to clinical data, including the referring department, primary questions or suspected diagnosis, and CT findings. It was identified if the clinical question was answered, whether the suspected diagnosis was confirmed or ruled out, and if additional findings (clinically significant or minor) were detected. Results The largest clinical subgroup was the hematooncological subgroup (n = 987), with frequent questions for inflammation/pneumonia (66 % in this subgroup). Overall, CT provided conclusive results in 97.6 % of all scans. In 1380 scans (70 %), the suspected diagnosis was confirmed. In 406/2019 cases (20 %), the CT scan was negative also in terms of an additional finding. In 8 of 9 clinical categories, the proportion of positive results was over 50 %. There were predominantly negative results (110/179; 61 %) in pre-stem cell transplant evaluation. In the subgroup of trauma management, 81/144 exams (57 %) showed positive results, including combined injuries (n = 23). 222/396 (56 %) of all additional findings were estimated to be clinically significant. Conclusion In a specialized center, the effectiveness of pediatric chest CT was excellent when counting the conclusive results. However, to improve efficiency, the clinical evaluation before imaging appears crucial to prevent unnecessary CT examinations. Key Points:  Citation Format

Sign in / Sign up

Export Citation Format

Share Document