Molecular Detection of Drug Resistance to Anti Leprosy Drugs in an Endemic Population

Abstract

Understanding the magnitude of drug resistance is important to keep current Multi Drug therapy effective and to prevent the spread of drug resistance. The study aimed to monitor the level of drug resistance in patients who have not been treated previously; patients treated previously who did not respond to treatment and patients who relapsed for multi drug therapy diagnosed by MFP assay and Molecular detection methods. AIM: To describe the prevalence and profile of drug resistance to anti-leprosy drugs in patients attending the Schieffelin Leprosy Research and Training Centre (SLRTC), Karigiri. OBJECTIVES: 1. To standardize a PCR (Polymerase chain Reaction) based Molecular technique to determine the prevalence of drug resistance among 7 Untreated newly diagnosed leprosy patients 2 Patients who have completed MB-MDT (12 doses) and who are still smear positive or those who have not shown the expected 1 log decline in Bacteriological index while on treatment 7 Patients who have relapsed after completing MDT. 2. To compare the prevalence of Drug Resistant isolates by PCR with the conventional MFP assay technique. 3. To identify the mutations seen among Drug Resistance by Gene Sequencing. Detection of drug resistant cases by Mutation detection in the drug resistance-determining region of the genome is a practical, cumbersome, rapid and highly sensitive method for monitoring resistance. The longitudinal surveillance of levels of drug resistance in new cases by mutation detection in areas with a high prevalence of leprosy will contribute to predict the magnitude of drug resistant Strains. Monitoring the susceptibility of isolates by Mutation detection in leprosy relapse cases and in cases where treatment failure seems a possibility allows optimal treatment to be chosen, by avoiding ineffective drugs and choosing effective compounds. Application of VNTR genotyping among the documented drug resistant cases to study the association or evolution of particular Strains will throw light existence of resistant sub-Strains of M.leprae.