A comparative and combinatorial study on two serological assays for detection of Mycobacterium leprae infection.

The performances of two Mycobacterium leprae specific serological assays namely: phenolicglycolipid-l-based enzyme-linked immunosorbent assay (PGL-ELISA) and a monoclonal antibody-based inhibition test (MAIT) were studied for there efficiency to detect M. leprae infection. As usual, both the tests were more sensitive to detect lepromatous leprosy patients than tuberculoid type of leprosy patients. Considering the efficiency to detect leprosy patients, the MAIT was slightly more sensitive and specific than PGL-ELISA. When the results of both assays are considered together, a better sensitivity (over the sensitivity of individual assay) was obtained while maintaining good enough specificity. These findings point out that a combinatorial approach for detection of M. leprae infection would be a better strategy to detect M. leprae infection. Hence, it may act as a better tool for measurement of bacterial load in the patients.