[Study of rifampin and dapsone resistance in three patients with recurring leprosy]

To detect the presence of rifampin- and dapsone-resistant strains of Mycobacterium leprae in three patients with recurring leprosy and clinically-suspected antimicrobial resistance through molecular techniques.

A retrospective, descriptive study was conducted of three multibacillary patients at the "Agua de Dios" Sanitarium in Cundinamarca, Colombia, that presented leprosy relapses that were documented by medical history, bacilloscopy, and biopsy. Biopsies were taken of the skin lesions and the bacteria were subject to DNA extraction and purification. Regions of the rpoB and folP1 genes associated with antimicrobial resistance were amplified and subjected to touch-down polymerase chain reaction and the amplified products were sequenced using the Sanger method.

A punctual mutation was identified in nucleotide 1367 of the rpoB gene in two of the samples studied. This mutation was not found in the folP1 gene of any of the three patients.

The mutation identified showed strains of rifampin-resistant M. leprae in two of the three patients with recurring leprosy. Mutations that indicate dapsone-resistance were not detected in any of the three patients.