scholarly journals Evaluation of Eight Serological Tests for Diagnosis of Imported Schistosomiasis

2012 ◽  
Vol 19 (6) ◽  
pp. 948-953 ◽  
Author(s):  
Hans-Friedemann Kinkel ◽  
Sabine Dittrich ◽  
Britta Bäumer ◽  
Thomas Weitzel
Keyword(s):  
Antibody Test ◽  
Parasitic Infections ◽  
Serum Samples ◽  
Serological Tests ◽  
Content Type ◽  
Commercial Kits ◽  
Few Data ◽  
Indirect Immunofluorescent ◽  
Positive Results ◽  
Immunofluorescent Antibody Test

ABSTRACTThe diagnosis of schistosomiasis in individuals from countries where the disease is not endemic is challenging, and few data are available on the accuracy of serological diagnosis in those patients. We evaluated the performance of eight serological assays, including four commercial kits, in the diagnosis of imported schistosomiasis in individuals from areas where the disease is not endemic, including six enzyme-linked immunosorbent assays using three different antigens, an indirect hemagglutination assay, and an indirect immunofluorescent-antibody test. To analyze the assays, we used a total of 141 serum samples, with 121 derived from patients with various parasitic infections (among which were 37 cases of schistosomiasis) and 20 taken from healthy volunteers. The sensitivity values for detection of schistosomiasis cases ranged from 41% to 78% and were higher forSchistosoma mansonithan forS. haematobiuminfections. Specificity values ranged from 76% to 100%; false-positive results were most frequent for samples from patients with cestode infections. By combining two or more tests, sensitivity improved markedly and specificity decreased only moderately. Serological tests are useful instruments for diagnosing imported schistosomiasis in countries where the disease is not endemic, but due to limitations in test sensitivities, we recommend the use of two or more assays in parallel.

scholarly journals Serodiagnosis of Visceral Leishmaniasis in Northeastern Italy: Evaluation of Seven Serological Tests

2020 ◽  
Vol 8 (12) ◽  
pp. 1847
Author(s):  
Margherita Ortalli ◽  
Daniele Lorrai ◽  
Paolo Gaibani ◽  
Giada Rossini ◽  
Caterina Vocale ◽  
...  
Keyword(s):  
Visceral Leishmaniasis ◽  
Western Blot ◽  
Rapid Test ◽  
Antibody Test ◽  
Screening Tests ◽  
Serum Samples ◽  
Serological Tests ◽  
Northeastern Italy ◽  
Indirect Immunofluorescent ◽  
Immunofluorescent Antibody Test

This study compares the performance of seven assays, including two ELISA (Leishmania ELISA IgG + IgM, Vircell Microbiologists; Leishmania infantum IgG ELISA, NovaTec), three rK39-based immunochromatographic tests (rK39-ICTs) (Leishmania Dipstick Rapydtest, Apacor; On Site Leishmania IgG/IgM Combo Rapid Test, CTK Biotech; LEISHMANIA Strip quick Test, Cypress Diagnostic), one indirect immunofluorescent antibody test (IFAT) (Leishmania-Spot IF, BioMérieux), and one western blot (WB) (Leishmania WESTERN BLOT IgG, LDBio Diagnostics) for serodiagnosis of visceral leishmaniasis (VL). Serum samples from 27 VL patients living in northeastern Italy were analyzed, as well as the serum samples from 50 individuals in whom VL diagnosis was excluded. The WB and the IFAT had 96% sensitivity, followed by the ELISA (63% and 74%, respectively). The rK39-ICT exhibited the worst performance among the serological tests, with sensitivities ranging from 52% to 70%. By combining selected ELISA/ICT, the sensitivity of VL detection reached 89%. IFAT and WB outperformed ELISA and rK39-ICT by possessing optimal sensitivity, but their high cost and complexity of execution would not allow their employment as screening tests. In conclusion, the combination of easy-to-perform tests, such as ICT and ELISA, could improve sensitivity in the serodiagnosis of Mediterranean VL.

scholarly journals An epidemic ofMycoplasma pneumoniaein Manitoba: A Serological Report

1993 ◽  
Vol 4 (1) ◽  
pp. 43-46 ◽  
Author(s):  
Laila Sekla ◽  
Walter Stackiw ◽  
Gudrun Eibisch ◽  
Donna Kolton
Keyword(s):  
Complement Fixation Test ◽  
Complement Fixation ◽  
Respiratory Infections ◽  
Antibody Test ◽  
Fixation Test ◽  
Age Group ◽  
Serological Tests ◽  
Igm Antibodies ◽  
Indirect Immunofluorescent ◽  
Immunofluorescent Antibody Test

Objectives: To report an epidemic ofMycoplasma pneumoniaein Manitoba and to discuss the limitations of the serodiagnostic tests used.Design: A retrospective analysis of the results of a province-wide serological testing for respiratory infections caused byM pneumoniae,using a complement fixation test and an indirect immunofluorescent antibody test for the detection of immunoglobulin (Ig) M antibodies.Material: From April 1, 1987, to March 31, 1991, 12,804 sera were tested and a serological diagnosis of recentM pneumoniaeinfections were established in 509 (3.97%). From April 1 to September 30, 1991, an additional 2088 persons were tested; the 158 (7.5%) recent cases ofM pneumoniaewere subjected to analysis.Results: Compared with the previous three years, an increase in the number of recent cases ofM pneumoniaewas first noticed in July 1990 which persisted until September 1991. Of 856 single sera tested, 59 (6.8%) were recentM pneumoniaeinfections and 56 (96.1%) of these were positive for IgM antibodies. Of the 616 persons who submitted paired sera, 99 (16%) were recent infections, but only 46 (46.4%) had IgM antibodies. Primary infections (ie, positive for IgM antibodies) were detected in 102 (64.5%) and reinfections (ie, positive complement fixation test only) in the remaining 56 persons with recentM pneumoniaeinfections. Primary infections were detected more frequently in the ‘under 16’ than in the ‘over 16’ year age group (75% versus 55.8% of the recent cases ofM pneumoniaein each age group). Reinfections were more common in the older age group. Of the 158 recent cases ofM pneumoniae,30.3% had a pneumonia; of these, 21 (55.2%) were under the age of 16 years.Discussion:M pneumoniaeis an important cause of morbidity. Serological tests are used for the diagnosis despite their limitations. The detection of IgM antibodies in acute serum establishes a diagnosis of primaryM pneumoniae;however, their absence does not excludeM pneumoniae. Asecond (convalescent) blood test is required to diagnose all primary infections. To diagnose all reinfections, paired sera should be tested by complement fixation.Summary: Manitoba experienced an epidemic ofM pneumoniaein 1990–91. Properly selected serological tests can provide a specific and rapid diagnosis.

scholarly journals Intra-uterine exposure of horses to Sarcocystis spp. antigens

2016 ◽  
Vol 68 (2) ◽  
pp. 271-275 ◽  
Author(s):  
A.M. Antonello ◽  
G.C. Cadore ◽  
F.L. Pivoto ◽  
G. Camillo ◽  
P. Braunig ◽  
...  
Keyword(s):  
Specific Antibody ◽  
Antibody Test ◽  
Immunoblot Analysis ◽  
Antibody Responses ◽  
Southern Brazil ◽  
Serum Samples ◽  
Immunofluorescent Antibody ◽  
Sarcocystis Spp ◽  
Indirect Immunofluorescent ◽  
Immunofluorescent Antibody Test

The aim of this study was to examine the intra-uterine exposure to Sarcocystis spp. antigens, determining the number of foals with detectable concentrations of antibodies against these agents in the serum, before colostrum ingestion and collect data about exposure of horses to the parasite. Serum samples were collected from 195 thoroughbred mares and their newborns in two farms from southern Brazil. Parasite specific antibody responses to Sarcocystis antigens were detected using the indirect immunofluorescent antibody test (IFAT) and immunoblot analysis. In 84.1% (159/189) of the pregnant mares and in 7.4% (14/189) of foals we detected antibodies anti-Sarcocystis spp. by IFAT. All samples seropositive from foals were also positive in their respective mares. Serum samples of seropositive foals by IFAT, showed no reactivity on the immunoblot, having as antigens S. neurona merozoites. In conclusion, the intra-uterine exposure to Sarcocystis spp. antigens in horses was demonstrated, with occurrence not only in mares, but also in their foals, before colostrum ingestion these occurrences were reduced.

scholarly journals COMPARISON OF A RAPID ENZYME-LINKED IMMUNOSORBANT ASSAY TEST WITH AN INDIRECT IMMUNOFLUORESCENT ANTIBODY TEST IN DIAGNOSING EHRLICHIA AND ANAPLASMA INFECTIONS IN DOGS

2019 ◽  
Vol 17 (4) ◽  
pp. 346-352
Author(s):  
Kr. Gospodinova ◽  
G. Zhelev ◽  
V. Petrov
Keyword(s):  
Serum Antibody ◽  
Rapid Test ◽  
Antibody Test ◽  
Diagnostic Value ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Immunofluorescent Antibody ◽  
Antibody Titers ◽  
Indirect Immunofluorescent ◽  
Immunofluorescent Antibody Test

PURPOSE: The objective of this study is to compare the diagnostic value of commercial enzyme-linked immunosorbent assay (ELISA) with indirect immunofluorescent antibody test (IFA) in detecting immunoglobulin-G (IgG) antibodies to Ehrlichia canis and Anaplasma phagocytophilum. METHODS: Seventy-four serum samples, obtained from dogs believed to be naturally infected with E. canis or A. phagocytophilum, were analyzed. RESULTS: By ELISA, 48 (64.9%) samples were found positive for IgG to E. canis, 10 (13.5%) to A. phagocytophilum, 12 (16.2%) to both E. canis and A. phagocytophilum, and in 4 (5.4%) samples no presence of antibodies was detected. The number of serologically positive dogs for IgG was 44 (59.5%) to E. canis, 10 (13.5%) to A. phagocytophilum, 16 (21.6%) to both E. canis and A. phagocytophilum, and 4 (5.4%) were determined negative by means of IFA. In most samples the antibody titer did not exceed 1:80 but in 5 it reached a level of 1:320, and in other 4 of even above 1:640. CONCLUSIONS: This study shows that IFA assay is more sensitive than commercial ELISA rapid test when serum antibody titers are low.

scholarly journals Correlation of the commercial anti-SARS-CoV-2 receptor binding domain antibody test with the chemiluminescent reduction neutralizing test and possible detection of antibodies to emerging variants

2021 ◽  
Author(s):  
Yoshitomo Morinaga ◽  
Hideki Tani ◽  
Yasushi Terasaki ◽  
Satoshi Nomura ◽  
Hitoshi Kawasuji ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Disease Onset ◽  
Antibody Test ◽  
Binding Domain ◽  
Receptor Binding Domain ◽  
Healthy Individuals ◽  
Wild Type ◽  
Serum Samples ◽  
Serological Tests ◽  
Convalescent Phase

Background Serological tests are beneficial for recognizing the immune response against SARS-CoV-2. To identify protective immunity, optimization of the chemiluminescent reduction neutralizing test (CRNT), using pseudotyped SARS-CoV-2, is critical. Whether commercial antibody tests are comparably accurate is unknown. Methods Serum samples collected before variants were locally found were obtained from confirmed COVID-19 patients (n = 74), confirmed non-COVID-19 individuals (n = 179), and unscreened individuals (suspected healthy individuals, n = 229). The convalescent phase was defined as the period after day 10 from disease onset. The CRNT against pseudotyped viruses displaying the wild-type spike protein and a commercially available anti-receptor binding domain (RBD) antibody test were assayed. The CRNT was also assayed, using South African (SA) and United Kingdom (UK)-derived variants. Results The CRNT (cut off value, 50% inhibition) and the anti-RBD antibody test (cut off value, 0.8 U/mL) concurred regarding symptomatic COVID-19 patients in the convalescent phase and clearly differentiated between patients and suspected healthy individuals (sensitivity; 95.8% and 100%, specificity; 99.1% and 100%, respectively). Anti-RBD antibody test results correlated with neutralizing titer (r = 0.47, 95% CI 0.20-0.68). Compared with the wild-type, CRNT reduction was observed for the SA and UK-derived variants. Of the samples with ≥100 U/mL by the anti-RBD antibody test, 77.8% and 88.9% showed ≥50% neutralization against the UK and the SA variants, respectively. Conclusion The CRNT and commercial anti-RBD antibody test effectively classified convalescent COVID-19 patients. The strong positive results using the commercial antibody test can reflect neutralizing activity against emerging variants.

scholarly journals Prokaryotic Expression and Antigenic Characterization of Three Recombinant Leishmania Antigens for Serological Diagnosis of Canine Leishmaniasis

2003 ◽  
Vol 10 (6) ◽  
pp. 1153-1156 ◽  
Author(s):  
S. Rosati ◽  
M. Ortoffi ◽  
M. Profiti ◽  
A. Mannelli ◽  
W. Mignone ◽  
...  
Keyword(s):  
Antibody Test ◽  
Canine Leishmaniasis ◽  
Gene Fragment ◽  
Leishmania Chagasi ◽  
Serological Tests ◽  
Reading Frame ◽  
Antigenic Characterization ◽  
Immunofluorescent Antibody Test ◽  
Immunodominant Epitopes

ABSTRACT Three recombinant antigens of Leishmania chagasi (= L. infantum) were expressed in prokaryotic systems and evaluated (using a panel of dog sera characterized by parasitological and serological immunofluorescent antibody test [IFAT] techniques) as diagnostic markers of infection. The whole open reading frame encoding K9, the gene fragment encoding the repetitive sequence of K26, and the 3′-terminal gene fragment encoding a single 39-amino-acid subunit of the kinesin-related protein K39 (K39sub) were amplified from L. infantum DNA and cloned into a pGEX-2T expression vector in frame with glutathione S-transferase (GST). The sensitivity and specificity of enzyme-linked immunosorbent assays (ELISAs) using K26 as an antigen (evaluated with sera from 20 parasitologically positive and 20 parasitologically negative dogs) were both 100% (95% confidence interval [CI] = 83.2 to 100). When K9 and K39sub were used, sensitivity was 95% (95% CI = 75.1 to 99.9) and specificity was 100% (95% CI = 83.2 to 100). Using 182 field sera, a good agreement was found between the recombinant K26 ELISA and IFAT (K = 0.92; 95% CI = 0.86 to 0.98) results and between the K9 and K39sub ELISA (used in parallel) and IFAT (K = 0.87; 95% CI = 0.80 to 0.95) results. The results demonstrate that each antigen carries immunodominant epitopes and that their combination may further increase the sensitivity of currently available serological tests.

Sign in / Sign up

Export Citation Format

Share Document