scholarly journals DETECTION OF TOXOPLASMOSIS IN CATS AND SHEEP

2021 ◽  
Vol 26 (1) ◽  
pp. 159-164
Author(s):  
Osama J. Kallo
Keyword(s):  
Antibody Titer ◽  
Antibody Test ◽  
Latex Agglutination ◽  
Agglutination Test ◽  
Recurrent Abortion ◽  
Serum Samples ◽  
Serological Tests ◽  
Fecal Samples ◽  
Antibody Titers ◽  
Latex Test

Thirty-three fecal samples from cats were examined for the presence of Toxoplasma oocysts, and another 33 serum samples from these cats were subjected for Latex agglutination test & indirect immunofluorecent antibody test. Also 80 serum samples from ewes were subjected to the same serological tests. The study indicated that the prevalence of Toxoplasma oocysts in cats was 27.3%. Higher rates of antibody titer (68%) were observed in cats tested with latex test. Infection in young cats was higher than in adults. Sixty percentage of ewes were sero-positive with Latex test, but only 35% were sero-positive with IFAT, higher prevalence of antibody titers was observed in sheep from the three locations of Iraq. Ewes that had recurrent abortion showed higher prevalence in both tests than non aborted ewes.

scholarly journals Serological Evaluation of Specific-Antibody Levels in Patients Treated for Chronic Chagas' Disease

2007 ◽  
Vol 15 (2) ◽  
pp. 297-302 ◽  
Author(s):  
Olga Sánchez Negrette ◽  
Fernando J. Sánchez Valdéz ◽  
Carlos D. Lacunza ◽  
María Fernanda García Bustos ◽  
María Celia Mora ◽  
...  
Keyword(s):  
Chagas Disease ◽  
Treatment Effectiveness ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Serological Tests ◽  
Recombinant Antigens ◽  
Antibody Titers ◽  
Laboratory Procedures ◽  
The Individual ◽  
Antibody Levels

ABSTRACT Serological tests are the main laboratory procedures used for diagnosis during the indeterminate and chronic stages of Chagas' disease. A serological regression to negativity is the main criterion used to define parasitological cure in treated patients. The aim of this work was to monitor the individual specificities of antibody levels for 3 years posttreatment in 18 adult patients. Conventional serological techniques (hemagglutination assays and enzyme-linked immunosorbent assay [ELISA]) were modified by using recombinant antigens to detect early markers of treatment effectiveness. For this purpose, serum samples were taken before and during treatment and every 6 months after treatment for at least 3 years. When hemagglutination assays were used, a decrease in antibody levels was observed in only one patient. When ELISA with serum dilutions was used, antibody clearance became much more apparent: in 77.7% (14/18) of the patients, antibody titers became negative with time. This was observed at serum dilutions of 1/320 and occurred between the 6th and the 30th months posttreatment. The immune response and the interval for a serological regression to negativity were different for each patient. For some of the recombinant antigens, only 50% (9/18) of the patients reached the serological regression to negativity. Recombinant antigen 13 might be a good marker of treatment effectiveness, since 66.6% (six of nine) of the patients presented with an early regression to negativity for specific antibodies to this antigen (P = 0.002).

scholarly journals Validation of a new automated chemiluminescent anti-SARS-CoV-2 IgM and IgG antibody assay system detecting both N and S proteins in Japan

2020 ◽  
Author(s):  
RIn Yokoyama ◽  
Makoto Kurano ◽  
Yoshifumi Morita ◽  
Takuya Shimura ◽  
Yuki Nakano ◽  
...  
Keyword(s):  
Measurement System ◽  
False Positive ◽  
Laboratory Testing ◽  
Antibody Test ◽  
Measurement Range ◽  
Antibody Assay ◽  
Serum Samples ◽  
Igg Antibody ◽  
Antibody Titers ◽  
Pcr Test

PCR methods are presently the standard for the diagnosis of Coronavirus disease 2019 (COVID-19), but additional methodologies are needed to complement PCR methods, which have some limitations. Here, we validated and investigated the usefulness of measuring serum antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using the iFlash3000 CLIA analyzer. We measured IgM and IgG titers against SARS-CoV-2 in sera collected from 26 PCR-positive COVID-19 patients, 53 COVID-19-suspected but PCR-negative patients, and 20 and 100 randomly selected non-COVID-19 patients who visited our hospital in 2020 and 2017, respectively. The within-day and between-day precisions were regarded as good, since the coefficient variations were below 5%. Linearity was also considered good between 0.6 AU/mL and 112.7 AU/mL for SARS-CoV-2 IgM and between 3.2 AU/mL and 55.3 AU/mL for SARS-CoV-2 IgG, while the linearity curves plateaued above the upper measurement range. We also confirmed that the seroconversion and no-antibody titers were over the cutoff values in all 100 serum samples collected in 2017. These results indicate that this measurement system successfully detects SARS-CoV-2 IgM/IgG. We observed four false-positive cases in the IgM assay and no false-positive cases in the IgG assay when 111 serum samples known to contain autoantibodies were evaluated. The concordance rates of the antibody test with the PCR test were 98.1% for SARS-CoV-2 IgM and 100% for IgG among PCR-negative cases and 30.8% for SARS-CoV-2 IgM and 73.1% for SARS-CoV-2 IgG among PCR-positive cases. In conclusion, the performance of this measurement system is sufficient for use in laboratory testing.

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 Detection of avian reovirus antibodies in layer birds of small scale commercial farms in Dinajpur district of Bangladesh

2016 ◽  
Vol 1 (3) ◽  
pp. 612-621 ◽  
Author(s):  
Abdus Salam ◽  
Md Atiqul Haque ◽  
Md Mostafizer Rahman ◽  
Mir Rowshan Akter ◽  
Farzana Afroz
Keyword(s):  
Antibody Titer ◽  
Specific Antibody ◽  
Age Groups ◽  
Antibody Test ◽  
Enzyme Linked Immunosorbent Assay ◽  
Small Scale ◽  
Avian Reovirus ◽  
Serum Samples ◽  
Aged Group ◽  
Test Kit

The present study was conducted on layer birds of different age groups to determine specific antibody titer level against avian reovirus (ARV) by indirect enzyme linked immunosorbent assay (iELISA) at Dinajpur district of Bangladesh. This study showed that ARV specific antibody positive cases were 84 out of 90 blood serum samples and the highest antibody titer was 26120 and lowest antibody titer was 288. The total 93.33% sera samples were showed positive result. The study showed that 100% sera sample were positive against ARV at 6 weeks of aged group and the highest, lowest and mean antibody titer were 13917, 4895 and 10269 respectively. On the other hand 88.88% sera sample were positive against ARV at 10 weeks of aged group and the highest, lowest and mean antibody titer were 9779, 288 and 5689.89 respectively. The sera sample collected from 14 weeks of aged group showed 88.88% positive and the highest, lowest and mean antibody titer were 11727, 871 and 5250 respectively. The sera sample collected from 18 weeks of aged group showed 88.88% positive against ARV and the highest, lowest and mean antibody titer were 24440, 1234 and 12648.89 respectively. The sera sample collected from 22 weeks of aged group were 100% positive against ARV and the highest, lowest and mean antibody titer were 26120, 1752 and 11373.89 respectively. The sera sample collected from 26 weeks of aged group showed 100% positive against ARV and the highest, lowest and mean antibody titer were 8566, 1630 and 4327.44 respectively. The sera sample collected from 30 weeks of aged group showed 100% positive against ARV and the highest, lowest and mean antibody titer were 13431, 1989 and 5890.56 respectively. The sera sample collected from 40 weeks of aged group showed 77.77% positive against ARV and the highest, lowest and mean antibody titer were 14618, 433 and 5103.22 respectively. The sera sample collected from 48 weeks of aged group showed 88.88% positive against ARV and the highest, lowest and mean antibody titer were 14553, 957 and 7436.5 respectively. In conclusion it is evident that avian reovirus-specific antibody was successfully detected through commercially available avian reovirus antibody test kit (ELISA kit) and the virus induced a significant antibody titer indicating the affecting virus was absolutely ARV.Asian J. Med. Biol. Res. December 2015, 1(3): 612-621

scholarly journals Evaluation of an Indirect Immunofluorescence Assay for Strongyloidiasis as a Tool for Diagnosis and Follow-Up

2006 ◽  
Vol 14 (2) ◽  
pp. 129-133 ◽  
Author(s):  
Marina Boscolo ◽  
Maria Gobbo ◽  
William Mantovani ◽  
Monica Degani ◽  
Mariella Anselmi ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Antibody Titer ◽  
Indirect Immunofluorescence ◽  
Serum Antibody ◽  
Antibody Test ◽  
Strongyloides Stercoralis ◽  
Negative Control ◽  
Response To Treatment ◽  
Diagnostic Threshold ◽  
Antibody Titers

ABSTRACT The diagnostic accuracy of an indirect immunofluorescence antibody test (IFAT) for Strongyloides stercoralis at different serum antibody titers was evaluated. To assess diagnostic sensitivity, sera from 156 patients with known strongyloidiasis were collected. Negative control sera were obtained from a composite group of 427 subjects (blood donors and hospitalized patients). With an area under the receiver-operating characteristic plot of 0.98, the IFAT showed a high level of diagnostic accuracy for strongyloidiasis. An antibody titer of ≥1:20, with 97% sensitivity and 98% specificity, was identified as the diagnostic threshold with the best overall performance. Cross-reactions were evaluated with 41 additional samples from patients with other known helminth infections, and the IFAT detected low-titer positivity in only one subject with filariasis. A positive IFAT result at an antibody dilution of ≥1:80 was virtually 100% specific, with 71% sensitivity. To test the usefulness of the IFAT as a monitoring tool, the changes in specific-antibody titers after treatment in a group of 155 patients were evaluated. Seroreversion or a decrease in antibody titer of twofold or more was observed in 60% of the patients. Response to treatment was directly correlated to the initial antibody titer, and a baseline titer of ≥1:80 was identified as the best predictor of response. In conclusion, a positive IFAT result at an antibody dilution of ≥1:20 is the optimal cutoff for screening. A titer of ≥1:80, with virtually no false-positive result, is a reliable cutoff for a serological assessment of treatment efficacy and for inclusion in clinical trials.

scholarly journals A rapid latex agglutination test for the detection of anti-cysticercus antibodies in cerebrospinal fluid (CSF)

2002 ◽  
Vol 44 (1) ◽  
pp. 57-58 ◽  
Author(s):  
Sérgio M. ROCHA ◽  
Lisandra A. SUZUKI ◽  
Andréa D.T. da SILVA ◽  
Gisele C. ARRUDA ◽  
Cláudio L. ROSSI
Keyword(s):  
Diagnostic Tests ◽  
Chronic Headache ◽  
Viral Meningitis ◽  
Latex Agglutination ◽  
Agglutination Test ◽  
Latex Agglutination Test ◽  
Serum Samples ◽  
Neurologic Disorders ◽  
Specific Antigens ◽  
Additional Approach

Simple and rapid latex-based diagnostic tests have been used for detecting specific antigens or antibodies in several diseases. In this article, we present the preliminary results obtained with a latex agglutination test (LAT) for diagnosing neurocysticercosis by detection of antibodies in CSF. A total of 43 CSF samples were assayed by the LAT: 19 CSF samples from patients with neurocysticercosis and 24 CSF samples from patients with other neurologic disorders (neurosyphilis, n = 8; neurotoxoplasmosis, n = 3; viral meningitis, n = 4, chronic headache, n = 9). The LAT exhibited 89.5% sensitivity and 75% specificity. The use of LAT seems to be an additional approach for the screening of neurocysticercosis with advantage of simplicity and rapidity. Further studies could be performed using purified antigens and serum samples.

scholarly journals Distribution of Antibody against Erysipelothrix rhusiopathiae in Cattle

2001 ◽  
Vol 8 (3) ◽  
pp. 624-627 ◽  
Author(s):  
Takuo Sawada ◽  
Raafat Hassanein ◽  
Tohru Yamamoto ◽  
Takaharu Yoshida
Keyword(s):  
Agglutination Test ◽  
Erysipelothrix Rhusiopathiae ◽  
The South ◽  
Serum Samples ◽  
Swine Industry ◽  
The North ◽  
Antibody Titers ◽  
Clinical Cases

ABSTRACT Serum samples collected from 854 cattle in nine prefectures of Japan, from Hokkaido to Okinawa, between 1988 and 1992 were examined for presence of antibodies against Erysipelothrix rhusiopathiae by growth agglutination test. Most of the sera showed positive reactions, and the antibody titers ranged from below 4 to above 128. Seventy-six percent of the sera showed titers of 32 or above, and 34% showed titers of 128 or above. The titers had a tendency to be higher in the south and lower in the north and were clearly low in sera from areas with no swine industry. These results indicated that Japanese cattle had been infected with E. rhusiopathiae and that clinical cases of the disease were possible.

scholarly journals Evaluation of the performance of three serological tests for diagnosis of Leishmania infantum infection in dogs using latent class analysis

2020 ◽  
Vol 29 (4) ◽  
Author(s):  
Asier Basurco ◽  
Alda Natale ◽  
Katia Capello ◽  
Antonio Fernández ◽  
María Teresa Verde ◽  
...  
Keyword(s):  
Sensitivity And Specificity ◽  
Leishmania Infantum ◽  
Latent Class ◽  
Rapid Test ◽  
Antibody Test ◽  
Latent Class Models ◽  
Canine Leishmaniasis ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Serological Tests

Abstract Canine leishmaniasis (CanL) is a disease caused by Leishmania infantum. Serological methods are the most common diagnostic techniques used for the diagnosis of the CanL. The objective of our study was to estimate the sensitivity and specificity of one in-house ELISA kit (ELISA UNIZAR) and three commercially available serological tests (MEGACOR Diagnostik GmbH) including an immunochromatographic rapid test (FASTest LEISH®), an immunofluorescent antibody test (MegaFLUO LEISH®) and an enzyme-linked immunosorbent assay (MegaELISA LEISH®), using latent class models in a Bayesian analysis. Two hundred fifteen serum samples were included. The highest sensitivity was achieved for FASTest LEISH® (99.38%), ELISA UNIZAR (99.37%), MegaFLUO LEISH® (99.36%) followed by MegaELISA LEISH® (98.49%). The best specificity was obtained by FASTest LEISH® (98.43%), followed by ELISA UNIZAR (97.50%), whilst MegaFLUO LEISH® and MegaELISA LEISH® obtained the lower specificity (91.94% and 91.93%, respectively). The results of present study indicate that the immunochromatographic rapid test evaluated FASTest LEISH® show similar levels of sensitivity and specificity to the quantitative commercial tests. Among quantitative serological tests, sensitivity and specificity were similar considering ELISA or IFAT techniques.

scholarly journals Immunodiagnosis of histoplasmosis in a compromised host

1978 ◽  
Vol 8 (5) ◽  
pp. 558-565
Author(s):  
G A Land ◽  
J H Foxworth ◽  
K E Smith
Keyword(s):  
False Positive ◽  
Inflammatory Diseases ◽  
Latex Agglutination ◽  
Agglutination Test ◽  
Serological Tests ◽  
Screening Protocol ◽  
Immunosuppressed Patients ◽  
Yeast Phase ◽  
Positive Results ◽  
Compromised Patients

Three serological tests for the diagnosis of histoplasmosis were compared for sensitivity and specificity in serum from blood bank donors, patients with histoplasmosis, and infected or noninfected immunosuppressed patients. The histoplasmin latex agglutination test was positive in 9% of the normal patients, 33% of the histoplasmosis patients, and 61% of the noninfected immunosuppressed patients. Since the test is prone to many false-positive results in patients with inflammatory diseases or non-Histoplasma infections, it has limited potential as a screening test among compromised patients. Immunodiffusion and counterimmunoelectrophoresis using a mycelial antigen were found to be more sensitive than either test using a combined yeast and mycelial antigen or a pure yeast phase antigen. Counterimmunoelectrophoresis at pH 7.2 proved to be the test of choice for serodiagnosis of histoplasmosis, resolving 85% of the immunocompetent infected patients and 100% of the infected immunosuppressed patients. Results indicated that counterimmunoelectrophoresis in conjunction with immunodiffusion could be used as a screening protocol to determine infection in incoming patients in a cancer hospital.

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