ABSTRACT
Introduction: Leptospirosis is most widespread Zoonosis in the world, especially in Tropical and temperate regions with moist climate. Diagnosis of Leptospirosis according to clinical symptoms is difficult and uncertain due to lack of specific sign [s]. Leptospira is a fastidious bacterium. Isolation of these bacteria by culture is difficult, time consuming and hence doses not contribute to an early diagnosis. Specific antibodies against Leptospira appear from 6th day of disease onset. The Microscopic Agglutination Test [MAT] is most reliable assay but generally requires paired sera for detection of seroconversion and is considered too complex for routine use
Objective: We performed this study to final a simple and reliable method for diagnosis of acute human leptospirosis. ELISA is another common method for diagnosis of Leptospirosis
Materials and Methods: In summer of 2004, we examined 282 single sera of patients who were suspected of Leptospirosis by a commercial none quantities and an in-house semi quantative ELISA assays and compared their results with MAT
Results: Mean time of first taking blood samples were 6:36 after onset of symptoms. All specimens with titers >/=640 against a pathogenic serovar in MAT were regarded as confirmed leptospirosis [104 from 282]. All specimens which were positive in any IgM-ELISA assays were compared with the results of MAT. In our study, sensitivity, specifity, positive and negative predictive values of in house ELISA were 89.4%, 87%, 80.2% and 93.4% consequently but were 87.5%, 41.5%, 44.6% and 85% for comerical IgM-ELISA assay consequently
Conclusion: The results of our study show that IgM- ELISA assay is a reliable and sensitive method for diagnosis of acute leptospirosis and also show that in house semi quantative IgM ELISA was more specific and commercial qualitative IgM- ELISA was more sensitive