tailieunhanh - Molecular investigation of Rifampicin resistance in clinical isolates of Mycobacterium ulcerans in Côte D'ivoire

M. ulcerans is the etiologic agent of Buruli ulcer. The clinical diagnosis of infection with this mycobacterium is based on microbiological analyzes, including PCR, which uses the nucleotide sequences of the primers to detect the targeted sequences. Cases of rifampicin resistance were recorded in mice experimentally infected with M. ulcerans strains and treated with rifampicin in previous studies. In this study, clinical isolates were confirmed as M. ulcerans strains. These isolates are from samples of patients with Buruli ulcer. The PCR gave a positivity rate of for the detection of the IS 2404 sequence and made it possible to highlight the virulence gene in most of the strains studied with a positivity rate of for the detection of the sequence IS-KR. However, the RpoB gene could not be found in any of the strains. Thus it gives a positivity rate of 0% for the detection of this gene. The results show that most strains of M. ulcerans secrete mycolactone. The production of this toxin is the consequence of a mutation in the IS-KR gene. They also show that rifampicin has an effective bactericidal activity against M. ulcerans strains and that resistance to this antibiotic results from a mutation of the RpoB gene. | Molecular investigation of Rifampicin resistance in clinical isolates of Mycobacterium ulcerans in Côte D'ivoire