[Evaluation of reasons of the MDR M. tuberculosis strains dissemination by analysis of the rifampicin and/or isoniazid resistant isolates].

During the last years in Novosibirsk region of Russia the rate of TB patients infected by MDR strains of M. tuberculosis has been constantly increasing. This increase may occur as a result of the spontaneously mutated mycobacterium selection during treatment of patients or as a result of primary infection by the resistant M.