Molecular detection of multi drug resistant Mycobacterium leprae from Indian leprosy patients.
OBJECTIVE: Emergence of multi drug resistant (MDR) organism for any infectious disease is a public health concern. Global efforts to control leprosy by intensive chemotherapy have led to a significant decrease in the number of registered patients. Currently recommended control measures for treating leprosy with MDT was designed to prevent the spread of dapsone resistant strains of Mycobacterium leprae. We report here the identification of MDR strains of M. leprae from relapsed leprosy patients from endemic regions in India.
METHODS: The drug resistant profiles of the isolated strains were confirmed by the identification of mutations in genes previously shown to be associated with resistance to each drug (Rifampicin, Dapsone and Ofloxacin). Between 2009 and 2016, slit- skin smears samples were collected from 239 relapse and 11 new leprosy cases from hospitals of The Leprosy Mission across India. DNAs were extracted from these samples and were analyzed for PCR targeting genes rpoB, folP and gyrA associated with drugs (Rifampicin, Dapsone and Ofloxacin) in M. leprae. Thai-53 (Wild-type) and Zensho 4 (MDR) strains were used as reference strains.
RESULTS: Fifteen strains showed representative mutations in at least 2 drug resistant genes. Two strains showed mutation in all 3 genes responsible for resistance. Seven strains showed mutation in genes responsible for rifampicin and dapsone and 7 strains showed mutation in genes responsible for resistance to dapsone and ofloxacin and one with rifampicin and ofloxacin.
CONCLUSION: The study showed emergence of MDR strains of M.leprae in MDT treated leprosy patients from endemic regions of India.