GENOTYPIC AND PHENOTYPIC COMPARISON OF DRUG RESISTANCE PROFILES OF M. tuberculosis ISOLATES

We conducted a comparative analysis of drug resistance of M. tuberculosis isolates to first-line TB drugs. The diagnostic samples and cultures of M. tuberculosis from TB patients were tested in the Mari El Republic. It was established that the divergence between genotypic and phenotypic isoniazid resistance did not exceed 4%, and rifampicin resistance – 3.9%. In most cases there was lack of mutations associated with resistance to isoniazid or rifampicin in the presence of phenotypic resistance. However, the divergence between results obtained by genotypic and different phenotypic methods was not only seen for M. tuberculosis isolates genotypically referred to sensitive, but also for M. tuberculosis isolates genotypically referred to resistant.