Abstract：Loop-mediated isothermal amplification has been widely used in pathogenic bacteria inspection. There is a lack of diagnostic tests for leptospirosis in technology-restricted settings or in emergency assistance activities. We developed and evaluated a loop-mediated isothermal amplification (LAMP) method for the rapid detection of pathogenic Leptospira spp. through amplification of lipL32 gene coding for the outer membrane protein LipL32. Specificity was high as we observed positive reactions of 27 pathogenic strains but negative reactions for other bacterial species. The lower limit of detection was 200 genomic equivalents/μL, and the sensitivity of LAMP was 100 times higher than that of PCR. The method enables detection of 200 leptospiral cells/μL following boiling of specimens and 20 leptospiral cells/μL of DNA extraction kit means. The lamp assay is easy to perform and inexpensive, so might be applied in the rapid and specific diagnosis of Leptospira.
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2015, Vol. 31 
