Genotyping comparison of Mycobacterium leprae isolates by VNTR analysis from nasal samples in a Brazilian endemic region.

This study analyzed the genetic diversity by MIRU-VNTR of Mycobacterium leprae isolates from nasal cavities and related to epidemiological and clinical data. The sample consisted of 48 newly diagnosed leprosy cases that tested positive for M. leprae PCR in nasal secretion (NS) attending to the National Reference Center of Dermatology Dona Libania (CDERM), Fortaleza, Brazil. Total DNA was extracted from NS of each patient and used for amplification of four M. leprae VNTR loci. Four clusters of M. leprae isolates were formed with identical genotypes. In the spatial analysis, 12 leprosy cases presented similar genotypes organized into 4 clusters. The most common genotypes in the current study was AC8b: 8, AC9: 7, AC8a: 8, GTA9: 10, which may represent a genotype of circulating strains most often in Ceará. A minimum set of four MIRU-VNTR loci was demonstrated to study the genetic diversity of M. leprae isolates from NS.