Diagnostic specificity and sensitivity changes in different settings

BMJ ◽  
2002 ◽  
Vol 324 (7336) ◽  
pp. 0f-0
Keyword(s):  
Diagnostic Specificity ◽  
Specificity And Sensitivity ◽  
Sensitivity Changes

scholarly journals Molecular characterization and Immunodiagnostic potential of various antigenic proteins of Fasciola gigantica species isolated from sheep of North West Himalayan Region

2019 ◽  
Vol 56 (2) ◽  
pp. 93-107
Author(s):  
J. S. Dar ◽  
B. A. Ganai ◽  
R. A. Shahardar ◽  
U. R. Zargar
Keyword(s):  
Small Ruminants ◽  
Fasciola Gigantica ◽  
Ovis Aries ◽  
Digenetic Trematode ◽  
Diagnostic Specificity ◽  
Immunoblotting Analysis ◽  
Accurate Identification ◽  
North West ◽  
Specificity And Sensitivity ◽  
Sds Page

SummaryThe control of the digenetic trematode Fasciola gigantica has been the major challenge in both cattle and small ruminants as there is a paucity of an effective and commercial vaccine. Thus, the accurate identification and prepatent diagnosis of F. gigantica is an essential prerequisite for its successful prevention and control. In the present study, the morphologically identified specimens isolated from the liver and bile ducts of sheep (Ovis aries) were validated through molecular data. The sequence analysis of ITS-2 of our isolates showed high degree of similarity with F. gigantica and F. hepatica using BLAST function of NCBI. The phylogenetic analysis of our isolates showed a close relationship with previously described F. gigantica and F. hepatica isolates from different countries. The antigenic profile of somatic and E/S antigens of F. gigantica were revealed by SDS–PAGE and immunoblotting using sera from sheep naturally infected with F. gigantica. By SDS-PAGE, 20 distinct bands were revealed from crude somatic fraction. Immunoblotting analysis of these proteins with positive sera exhibited 8 sero-reactive bands ranging from 14 to 97 kDa. Among these 38 and 44 kDa bands were quite specific with high diagnostic specificity and sensitivity. The E/S fraction comprised 7 distinct bands, as revealed by SDS-PAGE analysis. Immunoblotting analysis of these proteins with positive sera exhibited 6 antigenic bands ranging from 23 – 54 kDa. Among these 27 and 33 kDa were found to be quite specific with high diagnostic specificity and sensitivity. The present study concludes that the protein bands of 38 and 44 kDa in somatic fraction and 27 and 33 kDa in E/S fraction can be used for the immunodiagnostic purpose for this economically important parasite, which may also entice further studies regarding their vaccine potential.

scholarly journals Microsphere Suspension Array Assays for Detection and Differentiation of Hendra and Nipah Viruses

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Adam J. Foord ◽  
John R. White ◽  
Axel Colling ◽  
Hans G. Heine
Keyword(s):  
Human Health ◽  
Virus Type ◽  
Nipah Virus ◽  
Hendra Virus ◽  
Diagnostic Specificity ◽  
Suspension Array ◽  
Specificity And Sensitivity ◽  
Nucleoprotein N ◽  
Encoding Genes ◽  
Single Reaction

Microsphere suspension array systems enable the simultaneous fluorescent identification of multiple separate nucleotide targets in a single reaction. We have utilized commercially available oligo-tagged microspheres (Luminex MagPlex-TAG) to construct and evaluate multiplexed assays for the detection and differentiation of Hendra virus (HeV) and Nipah virus (NiV). Both these agents are bat-borne zoonotic paramyxoviruses of increasing concern for veterinary and human health. Assays were developed targeting multiple sites within the nucleoprotein (N) and phosphoprotein (P) encoding genes. The relative specificities and sensitivities of the assays were determined using reference isolates of each virus type, samples from experimentally infected horses, and archival veterinary diagnostic submissions. Results were assessed in direct comparison with an established qPCR. The microsphere array assays achieved unequivocal differentiation of HeV and NiV and the sensitivity of HeV detection was comparable to qPCR, indicating high analytical and diagnostic specificity and sensitivity.

scholarly journals INDIRECT ELISA FOR DETECTION OF ANTIBODIES TO FMDV NON-STRUCTURAL PROTEINS IN PORCINE SERA

2018 ◽  
pp. 13-20
Author(s):  
A. S. Yakovleva ◽  
A. V. Kanshina ◽  
A. V. Scherbakov
Keyword(s):  
Indirect Elisa ◽  
High Sensitivity ◽  
High Specificity ◽  
Structural Proteins ◽  
Post Inoculation ◽  
Nonstructural Proteins ◽  
Diagnostic Specificity ◽  
Fmd Virus ◽  
Specificity And Sensitivity ◽  
Sensitivity Specificity

An indirect variant of ELISA used for detection of antibodies to nonstructural proteins of the FMD virus in porcine blood sera was developed. The results of the validation showed that the developed method is characterized by high sensitivity, specificity and reproducibility. When testing the blood serum panel obtained from experimentally infected animals, the method allowed to detect antibodies to FMD virus in 7 of 18 sera collected on day 6 post inoculation, in 13 of 19 sera – on day 7 post inoculation, in 16 of 19 sera – on day 8 post inoculation and in all 76 sera obtained on days 9–12 post inoculation. The diagnostic specificity of 3AB-ELISA was 100% when testing 100 knowingly negative blood sera from pigs imported to Russia from Norway. High specificity and sensitivity of the method, established during the development of the method, are confirmed in the course of routine diagnostic tests.

Diagnostic Value of Serum Kallikrein-Related Peptidases 6 and 10 Versus CA125 in Ovarian Cancer

2011 ◽  
Vol 21 (4) ◽  
pp. 625-632 ◽  
Author(s):  
Mustafa Abdel Hafiz El Sherbini ◽  
Maha Mohamed Sallam ◽  
Emtiaz Abdel Kawy Shaban ◽  
Amr Hassan El-Shalakany
Keyword(s):  
Ovarian Cancer ◽  
Diagnostic Value ◽  
Maternity Hospital ◽  
Serum Markers ◽  
Enzyme Linked Immunosorbent Assay ◽  
Diagnostic Specificity ◽  
Preoperative Serum ◽  
Specificity And Sensitivity ◽  
Serum Ca125 ◽  
Oncology Unit

Objectives:To assess the diagnostic value of serum KLK6 and KLK10 in patients with ovarian tumor in comparison to serum CA125.Methods:Based on clinical and sonographic findings, 90 patients were consecutively recruited at the Gynecological Oncology Unit, Ain Shams University Maternity Hospital. Preoperative serum KLK6 and/or KLK10 were determined by enzyme-linked immunosorbent assay technique. The patients' final diagnoses were those of the histopathological reports.Results:There were 27 malignant versus 63 benign cases. Serum markers' diagnostic specificity and sensitivity were 80.3/72.7, 56.8/64.0, and 39.53/58.3 for CA125, KLK6, and KLK10, respectively. Combination of CA125 with either of the other 2 markers revealed diagnostic enhancement with KLK10 (85.37/73.00) but not with KLK6 (42.86/86.36).Conclusions:In ovarian cancer, serum KLK6 and KLK10 may have much lower overall sensitivities than serum CA125. However, whereas serum KLK6 may improve the sensitivity of CA125, serum KLK10 may have the highest specificity among the 3 markers.

Development and preliminary application of gE enzyme-linked immunosorbent assay for detection of the antibody to gE protein ofPseudorabies virusin pigs

2005 ◽  
Vol 2 (2) ◽  
pp. 79-83 ◽  
Author(s):  
Tang Yong ◽  
Chen Huan-Chun ◽  
Qin Ya-Li ◽  
He Qi-Gai ◽  
Jin Mei-Lli ◽  
...  
Keyword(s):  
Immunosorbent Assay ◽  
Pseudorabies Virus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Diagnostic Specificity ◽  
Serum Samples ◽  
Agreement Rate ◽  
Glycoprotein E ◽  
Recombinant Glycoprotein ◽  
Specificity And Sensitivity ◽  
Preliminary Application

AbstractTo differentiate pigs infected withPseudorabies virus(PrV) from pigs vaccinated with gE-PrV, a glycoprotein E enzyme-linked immunosorbent assay (gE-ELISA) based on recombinant glycoprotein E (gE) (which was expressed byEscherichia coli, purified, denatured and renatured) was developed. By testing 115 serum samples, the diagnostic specificity and sensitivity of the developed gE-ELISA were evaluated to be 94.5% and 96.7%, respectively. Five serum samples were tested with plates from five lots, and the results had a coefficient of variation of less than 10%, showing good reproducibility of gE-ELISA. This gE-ELISA was compared with a commercial blocking ELISA by testing 356 serum samples. The agreement rate of the two assays was 92.13% (328/356). These results suggested that the gE-ELISA developed in our laboratory could be used in differentiating PrV-infected and gE-PrV-vaccinated pigs.

scholarly journals Insulin, C-peptide and proinsulin for the biochemical diagnosis of hypoglycaemia related to endogenous hyperinsulinism

2007 ◽  
Vol 157 (1) ◽  
pp. 75-83 ◽  
Author(s):  
D Vezzosi ◽  
A Bennet ◽  
J Fauvel ◽  
P Caron
Keyword(s):  
Blood Glucose ◽  
Fasting Blood Glucose ◽  
Diagnostic Specificity ◽  
C Peptide ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Specificity And Sensitivity ◽  
Obese Subjects ◽  
Best Parameters ◽  
Rule Out

Objective: We evaluated the respective value of insulin, C-peptide and proinsulin levels in 33 patients with endogenous hyperinsulinism and in 67 controls to determine the best parameters and thresholds to make or to rule out the diagnosis of endogenous hyperinsulinism. Results: When blood glucose levels were below 2.5 mmol/l, insulin was <21 pmol/l in 8–35% of the patients and in all controls; C-peptide was >0.2 nmol/l in all insulinomas but not in the nesidioblastosis or in the controls; proinsulin was >5 pmol/l in all patients but not in the controls. When fasting blood glucose levels reached 2.5–3.3 mmol/l, proinsulin was <22 pmol/l in all the controls and >22 pmol/l in 74% of the patients. Proinsulin after an overnight fast was below 22 pmol/l in all non-obese controls and above 22 pmol/l in 73% of non-obese patients. Conclusion: Proinsulin levels above 5 pmol/l with blood glucose levels below 2.5 mmol/l during a 72 h fast test represent the best criterion for the diagnosis of endogenous hyperinsulinism, reaching 100% diagnostic specificity and sensitivity. Concomitant C-peptide levels above 0.2 nmol/l also make the diagnosis of all our insulinoma patients, not the diagnosis of nesidioblastosis, while insulin levels have much less diagnostic accuracy. Whether proinsulin levels above 22 pmol/l could also make the diagnosis of endogenous hyperinsulinism in part of the patients at the time of fasting blood glucose levels between 2.5 and 3.3 mmol/l or after an overnight fast in non-obese subjects needs further study.

Molecular characterization and immunodiagnostics of Dicrocoelium dendriticum species isolated from sheep of north-west Himalayan region

2020 ◽  
Vol 94 ◽  
Author(s):  
J.S. Dar ◽  
U. Shabir ◽  
S.A. Dar ◽  
B.A. Ganai
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Ovis Aries ◽  
Diagnostic Specificity ◽  
Immunoblotting Analysis ◽  
Accurate Identification ◽  
North West ◽  
Dicrocoelium Dendriticum ◽  
Specificity And Sensitivity ◽  
Sds Page

Abstract Despite its extensive presence among grazing ruminants, dicrocoeliosis, also known as ‘small liver fluke’ disease, is poorly known and often underestimated by researchers and practitioners in many countries. The accurate identification and prepatent diagnosis of Dicrocoelium dendriticum infection is an essential prerequisite for its prevention and control. In the present study, the morphologically identified specimens isolated from the bile ducts of sheep (Ovis aries) were validated through molecular data. The sequence analysis of the second internal transcribed spacer (ITS-2) of our isolates showed a high degree of similarity with D. dendriticum using the BLAST function of the National Center for Biotechnology Information (NCBI). The phylogenetic analysis of our isolates showed a close relationship with previously described D. dendriticum isolates from different countries. The antigenic profiles of somatic and excretory/secretory (E/S) antigens of D. dendriticum were revealed by sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) and immunoblotting using sera from sheep naturally infected with D. dendriticum. By SDS–PAGE, 16 distinct bands were revealed from crude somatic fraction. Immunoblotting analysis of these proteins with positive sera exhibited six seroreactive bands ranging from 27 to 130 kDa. Among these, the 84 and 130 kDa bands were quite specific, with high diagnostic specificity and sensitivity. The E/S fraction comprised nine distinct bands, as revealed by SDS–PAGE analysis. Immunoblotting analysis of these proteins with positive sera exhibited five antigenic bands ranging from 27 to 130 kDa. Among these, the 130 kDa band was found to be quite specific, with high diagnostic specificity and sensitivity. The present study concludes that the protein bands of 84 and 130 kDa in somatic fraction and 130 kDa in E/S fraction can be used for the immunodiagnostic purpose for this economically important parasite, which may also encourage further studies regarding their vaccine potential.

scholarly journals Sepsis Diagnostics in the Era of “Omics” Technologies

2018 ◽  
Vol 119 (1) ◽  
pp. 9-29 ◽  
Author(s):  
Miroslav Průcha ◽  
Roman Zazula ◽  
Stefan Russwurm
Keyword(s):  
Early Diagnosis ◽  
Clinical Course ◽  
Clinical Phenotype ◽  
Clinical Syndrome ◽  
Response To Therapy ◽  
Infectious Agents ◽  
Diagnostic Specificity ◽  
Patient Response ◽  
Omics Technologies ◽  
Specificity And Sensitivity

Sepsis is a multifactorial clinical syndrome with an extremely dynamic clinical course and with high diverse clinical phenotype. Early diagnosis is crucial for the final clinical outcome. Previous studies have not identified a biomarker for the diagnosis of sepsis which would have sufficient sensitivity and specificity. Identification of the infectious agents or the use of molecular biology, next gene sequencing, has not brought significant benefit for the patient in terms of early diagnosis. Therefore, we are currently searching for biomarkers, through “omics” technologies with sufficient diagnostic specificity and sensitivity, able to predict the clinical course of the disease and the patient response to therapy. Current progress in the use of systems biology technologies brings us hope that by using big data from clinical trials such biomarkers will be found.

scholarly journals A Highly Sensitive and Subspecies-Specific Surface Antigen Enzyme- Linked Immunosorbent Assay for Diagnosis of Johne's Disease

2006 ◽  
Vol 13 (8) ◽  
pp. 837-844 ◽  
Author(s):  
Shigetoshi Eda ◽  
John P. Bannantine ◽  
W. R. Waters ◽  
Yasuyuki Mori ◽  
Robert H. Whitlock ◽  
...  
Keyword(s):  
Immunosorbent Assay ◽  
Surface Antigens ◽  
Johne's Disease ◽  
Enzyme Linked Immunosorbent Assay ◽  
Diagnostic Specificity ◽  
Serum Samples ◽  
Low Level ◽  
Specificity And Sensitivity ◽  
Highly Sensitive ◽  
High Level

ABSTRACT Johne's disease (JD), or paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis, is one of the most widespread and economically important diseases of livestock and wild ruminants worldwide. Control of JD could be accomplished by diagnosis and good animal husbandry, but this is currently not feasible because commercially available diagnostic tests have low sensitivity levels and are incapable of diagnosing prepatent infections. In this study, a highly sensitive and subspecies-specific enzyme-linked immunosorbent assay was developed for the diagnosis of JD by using antigens extracted from the surface of M. avium subsp. paratuberculosis. Nine different chemicals and various intervals of agitation by vortex were evaluated for their ability to extract the surface antigens. Various quantities of surface antigens per well in a 96-well microtiter plate were also tested. The greatest differences in distinguishing between JD-positive and JD-negative serum samples by ethanol vortex enzyme-linked immunosorbent assay (EVELISA) were obtained with surface antigens dislodged from 50 μg/well of bacilli treated with 80% ethanol followed by a 30-second interval of agitation by vortex. The diagnostic specificity and sensitivity of the EVELISA were 97.4% and 100%, respectively. EVELISA plates that had been vacuum-sealed and then tested 7 weeks later (the longest interval tested) had diagnostic specificity and sensitivity rates of 96.9 and 100%, respectively. In a comparative study involving serum samples from 64 fecal culture-positive cattle, the EVELISA identified 96.6% of the low-level fecal shedders and 100% of the midlevel and high-level shedders, whereas the Biocor ELISA detected 13.7% of the low-level shedders, 25% of the mid-level shedders, and 96.2% of the high-level shedders. Thus, the EVELISA was substantially superior to the Biocor ELISA, especially in detecting low-level and midlevel shedders. The EVELISA may form the basis for a highly sensitive and subspecies-specific test for the diagnosis of JD.

Sign in / Sign up

Export Citation Format

Share Document