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Journal of Clinical Pathology May 1989The performance of a direct agglutination test for the detection of toxoplasma specific IgG immunoglobulin was compared with that of the latex agglutination test. The... (Comparative Study)
Comparative Study
The performance of a direct agglutination test for the detection of toxoplasma specific IgG immunoglobulin was compared with that of the latex agglutination test. The direct agglutination test was less sensitive but more specific than the latex agglutination test. Quantitative results were not directly comparable, reflecting the different antibody profiles detected in each assay. The direct agglutination test represents an alternative to the latex agglutination test as a screening test for toxoplasmosis. Patients at risk of life threatening infection require detailed serological examination using additional assays.
Topics: Agglutination Tests; Animals; Antibodies, Protozoan; Humans; Immunoglobulin G; Latex Fixation Tests; Toxoplasma; Toxoplasmosis
PubMed: 2732349
DOI: 10.1136/jcp.42.5.536 -
PloS One 2015Leptospirosis is diagnosed on clinical grounds, and confirmed by microscopic agglutination test (MAT). IgM-ELISA (Serion-Virion) and immunochromatography test... (Comparative Study)
Comparative Study
BACKGROUND
Leptospirosis is diagnosed on clinical grounds, and confirmed by microscopic agglutination test (MAT). IgM-ELISA (Serion-Virion) and immunochromatography test (Leptocheck-WB) are two immunodiagnostic assays for leptospirosis. Their sensitivity, specificity and applicability in Sri Lanka have not been systematically evaluated.
METHODS
Clinically diagnosed leptospirosis patients (n = 919) were recruited from three hospitals in the Western Province of Sri Lanka, during June 2012 to December 2013. MAT, IgM-ELISA and Leptocheck-WB were performed on all patient sera. MAT titer of ≥ 400 in single sample, four-fold rise or seroconversion ≥ 100 in paired samples were considered as positive for MAT. For diagnostic confirmation, MAT was performed during both acute and convalescent phases. Anti-leptospiral IgM ≥ 20 IU/ml and appearance of a band in the test window were considered as positive for IgM-ELISA and Leptocheck-WB test respectively. Patients with an alternative diagnosis (n = 31) were excluded. Data analysis was performed using two methods, i) considering MAT as reference standard and ii) using Bayesian latent class model analysis (BLCM) which considers each test as imperfect.
RESULTS
MAT, IgM-ELISA and Leptocheck-WB positivity were 39.8%, 45.8% and 38.7% respectively during the acute phase. Acute-phase MAT had specificity and sensitivity of 95.7% and 55.3% respectively, when compared to overall MAT positivity. IgM-ELISA and Leptocheck-WB had similar diagnostic sensitivity when compared with acute-phase MAT as the gold standard, although IgM-ELISA showed higher specificity (84.5%) than Leptocheck-WB (73.3%). BLCM analysis showed that IgM-ELISA and Leptocheck-WB had similar sensitivities (86.0% and 87.4%), while acute-phase MAT had the lowest sensitivity (77.4%). However, acute-phase MAT had high specificity (97.6%), while IgM-ELISA and Leptocheck-WB showed similar but lower specificity (84.5% and 82.9%).
CONCLUSIONS
Both IgM-ELISA and Leptocheck-WB shows similar sensitivities and specificities. IgM-ELISA may be superior to MAT during the acute phase and suitable for early diagnosis of leptospirosis. Leptocheck-WB is suitable as a rapid immunodiagnostic screening test for resource limited settings.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Agglutination Tests; Antibodies, Bacterial; Chromatography, Affinity; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunoglobulin M; Leptospira; Leptospirosis; Male; Middle Aged; Reagent Kits, Diagnostic; Sensitivity and Specificity; Young Adult
PubMed: 26086800
DOI: 10.1371/journal.pone.0129236 -
Journal of Clinical Laboratory Analysis Mar 2022The laboratory test results and serum-specific antibodies of patients with acute brucellosis initial infection were followed up and analyzed.
BACKGROUND
The laboratory test results and serum-specific antibodies of patients with acute brucellosis initial infection were followed up and analyzed.
METHODS
70 patients in Hohhot City, Inner Mongolia Autonomous Region, with acute brucellosis were followed up for 360 days. Serum samples were collected at 0, 15, 30, 60, 90, 180, and 360 days after diagnosis and analyzed by Rose Bengal plate test (RBPT), colloidal gold test paper (GICA), and test tube agglutination test (SAT). The serum-specific antibodies IgG and IgM were detected.
RESULTS
RBPT results: False negative (-) gradually increased with the extension of the course of disease, with the largest change in 30-60 days after diagnosis, and the constituent ratio increased by 12.9%. GICA results: The false negative increased with the course of disease, and the constituent ratio of false negative was 20.0% after 180 days of diagnosis. SAT results: 1:100 positive showed a ladder like decrease with the increase in the course of disease, and the largest decrease was 90-180 days, with a decrease of 34.3% in the constituent ratio. 360 days after diagnosis, the constituent ratio of positive was only 14.3%. During the follow-up period, the IgG average value fluctuated and the average IgM value decreased.
CONCLUSION
The false-negative results of RBPT, GICA, and SAT increased with the course of disease, and the false-negative rates were higher than 20% after half a year. IgM level is beneficial to the early diagnosis of brucellosis, while IgG level is helpful to the judgment of brucellosis stage.
Topics: Agglutination Tests; Antibodies, Bacterial; Brucellosis; Follow-Up Studies; Humans; Rose Bengal
PubMed: 35137464
DOI: 10.1002/jcla.24205 -
The American Journal of Tropical... Jun 2009Accuracy of an rK39 rapid diagnostic test (DiaMed-IT-Leish ) for visceral leishmaniasis (VL) was compared with splenic aspiration and the direct agglutination test (DAT)...
Field evaluation of rK39 test and direct agglutination test for diagnosis of visceral leishmaniasis in a population with high prevalence of human immunodeficiency virus in Ethiopia.
Accuracy of an rK39 rapid diagnostic test (DiaMed-IT-Leish ) for visceral leishmaniasis (VL) was compared with splenic aspiration and the direct agglutination test (DAT) in a population with a high prevalence of infection with human immunodeficiency virus (HIV) in Ethiopia. There were 699 patients clinically suspected of having VL (153 parasitologically confirmed, 482 DAT confirmed, and 130 DAT negative), and 97 DAT-negative controls. A total of 84% were tested for HIV and 34% were HIV positive. Sensitivity of the rK39 test in parasitologically confirmed VL patients was 84% (77% in HIV positive and 87% in HIV negative; P = 0.25). Sensitivity of the DAT was higher (94%; P = 0.01), 89% in HIV-positive patients and 95% in HIV-negative patients; P = 0.27). Specificity of the rK39 test was 99% in DAT-negative controls and 92% in DAT-negative patients clinically suspected of having VL. A diagnostic algorithm combining DAT and the rK39 test had a sensitivity of 98% in HIV-positive VL patients and 99% in HIV-negative VL patients. Despite the lower sensitivity in a population with a high prevalence of HIV, the DiaMed-IT-Leish rK39 test enables decentralization of diagnosis. Patients clinically suspected of having VL who show negative results on the rK39 antigen test should undergo follow-up DAT testing, especially if they are HIV positive.
Topics: Adult; Agglutination Tests; Ethiopia; Female; HIV Infections; Humans; Leishmaniasis, Visceral; Male; Odds Ratio; Prevalence; Reagent Kits, Diagnostic; Sensitivity and Specificity
PubMed: 19478251
DOI: No ID Found -
Journal of Clinical Pathology Jan 1990The presence of antibodies was determined in the serum and cerebrospinal fluid in six patients with neurobrucellosis using the Rose Bengal test, the microdilution... (Comparative Study)
Comparative Study
The presence of antibodies was determined in the serum and cerebrospinal fluid in six patients with neurobrucellosis using the Rose Bengal test, the microdilution agglutination test, and the Coombs' test. Four of the patients were followed up for more than three months. The Rose Bengal test and the microagglutination test were positive in cerebrospinal fluid in five of the six cases at some stage. The Coombs' test was positive in cerebrospinal fluid in every patient and in one was the only positive serological test. Cerebrospinal fluid positivity is not excluded by low titres or negative results of antibodies in the serum for any of the three methods. A Coombs' test or some equivalent must always be made on the cerebrospinal fluid to diagnose neurobrucellosis.
Topics: Adolescent; Adult; Agglutination Tests; Antibodies, Bacterial; Brucellosis; Central Nervous System Diseases; Coombs Test; Female; Humans; Male; Middle Aged; Rose Bengal; Time Factors
PubMed: 2312754
DOI: 10.1136/jcp.43.1.79 -
Journal of Clinical Microbiology Jun 1980A method that increases the sensitivity and specificity of the direct agglutination (AG) test for diagnosis of Toxoplasma gondii infection is described. Qualitative... (Comparative Study)
Comparative Study
A method that increases the sensitivity and specificity of the direct agglutination (AG) test for diagnosis of Toxoplasma gondii infection is described. Qualitative results in the Sabin-Feldman dye test (DT) and AG test were in excellent agreement (98%). Differences in titers between these two tests often related to the length of time the individual was infected. The AG test titer was most often lower than the DT titer during acute (recent) infection; the AG test titer was most often higher than the DT titer in older or chronic infection. If the AG test antigen described here can be made available, the AG test would be ideal for use as a screening test and would provide a simple and inexpensive means for the surveillance of seronegative women during pregnancy and for detection of seroconversions.
Topics: Agglutination Tests; Animals; Antibodies; Antigens; Fluorescent Antibody Technique; Humans; Immunoglobulin M; Mice; Toxoplasmosis
PubMed: 7000807
DOI: 10.1128/jcm.11.6.562-568.1980 -
Bulletin of the World Health... 1968Reviewing the literature on hydatid serology for the period 1958-66, the author concludes that the complement-fixation test is not the most sensitive procedure but may... (Review)
Review
Reviewing the literature on hydatid serology for the period 1958-66, the author concludes that the complement-fixation test is not the most sensitive procedure but may have value for postoperative evaluation. The haemagglutination, bentonite-flocculation and latex-agglutination tests are the procedures of choice at present. The fluorescent-antibody test shows much promise, but requires further evaluation. The intradermal test performed with standardized antigen is useful for diagnosis and epidemiological studies. Reliable serological diagnosis of hydatid disease in animals awaits the use of more specific antigen. Although many related species share common antigens with Echinococcus granulosus, the sensitivity of the diagnostic serological tests is high because of the strongly specific response elicited by the specific antigens used. the need for further standardization of both antigen and test procedure is pointed out.
Topics: Agglutination Tests; Animals; Antigens; Complement Fixation Tests; Echinococcosis; Fluorescent Antibody Technique; Hemagglutination Tests; Humans; Serologic Tests; Skin Tests
PubMed: 4882511
DOI: No ID Found -
BMJ (Clinical Research Ed.) Oct 2006To compare the performance of the direct agglutination test and rK39 dipstick for the diagnosis of visceral leishmaniasis. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To compare the performance of the direct agglutination test and rK39 dipstick for the diagnosis of visceral leishmaniasis.
DATA SOURCES
Medline, citation tracking, January 1986 to December 2004. Selection criteria Original studies evaluating the direct agglutination test or the rK39 dipstick with clinical visceral leishmaniasis as target condition; adequate reference classification; and absolute numbers of true positive, true negative, false positive, and false negative observations available or derivable from the data presented.
RESULTS
30 studies evaluating the direct agglutination test and 13 studies evaluating the rK39 dipstick met the inclusion criteria. The combined sensitivity estimates of the direct agglutination test and the rK39 dipstick were 94.8% (95% confidence interval 92.7% to 96.4%) and 93.9% (87.7% to 97.1%), respectively. Sensitivity seemed higher and more homogenous in the studies carried out in South Asia. Specificity estimates were influenced by the type of controls. In phase III studies carried out on patients with clinically suspected disease, the estimated specificity of the direct agglutination test was 85.9% (72.3% to 93.4%) and of the rK39 dipstick was 90.6% (66.8% to 97.9%).
CONCLUSION
The diagnostic performance of the direct agglutination test and the rK39 dipstick for visceral leishmaniasis is good to excellent and seem comparable.
Topics: Agglutination Tests; Enzyme-Linked Immunosorbent Assay; False Negative Reactions; False Positive Reactions; Humans; Leishmaniasis, Visceral; Sensitivity and Specificity
PubMed: 16882683
DOI: 10.1136/bmj.38917.503056.7C -
Indian Journal of Medical Microbiology 2010The laboratory diagnosis of leptospirosis is fraught with several problems. Isolation of Leptospira by culture has a low sensitivity and the microscopic agglutination... (Comparative Study)
Comparative Study
The laboratory diagnosis of leptospirosis is fraught with several problems. Isolation of Leptospira by culture has a low sensitivity and the microscopic agglutination test (MAT) is time consuming To overcome these problems, a rapid latex agglutination test (LAT) has been standardized for the detection of antileptospiral antibodies in serum samples from suspected cases of leptospirosis. We compared the efficiency of the LAT to a commercially available IgM ELISA and MAT. A total of 150 serum samples were tested by LAT, IgM ELISA, and MAT. The positivity was 26.7%, 26% and 24% respectively. The sensitivity and specificity of LAT as compared to MAT was 90.62 and 91.96% respectively. Even though LAT and ELISA showed similar results, its rapidity and simplicity made latex agglutination test more suitable as a rapid screening test.
Topics: Agglutination Tests; Antibodies, Bacterial; Bacteriological Techniques; Enzyme-Linked Immunosorbent Assay; Humans; Immunoglobulin M; Leptospira; Leptospirosis; Sensitivity and Specificity
PubMed: 20644313
DOI: 10.4103/0255-0857.66484 -
Preventive Veterinary Medicine Dec 2023When Bayesian latent class analysis is used for diagnostic test data in the absence of a gold standard test, it is common to assume that any unknown test sensitivities...
When Bayesian latent class analysis is used for diagnostic test data in the absence of a gold standard test, it is common to assume that any unknown test sensitivities and specificities are constant across different populations. Indeed this assumption is often necessary for model identifiability. However there are a number of practical situations, depending on the type of test and the nature of the disease, where this assumption may not be true. We present a case study of using a microscopic agglutination test to diagnose leptospiroris infection in beef cattle, which strongly suggests that sensitivity in particular varies among herds. We develop and fit an alternative model in which sensitivity is related to within-herd prevalence, and discuss the statistical and epidemiological implications.
Topics: Cattle; Animals; Bayes Theorem; Leptospirosis; Cattle Diseases; Agglutination Tests; Prevalence; Sensitivity and Specificity
PubMed: 37976969
DOI: 10.1016/j.prevetmed.2023.106074