Abstract: | The study was undertaken to determine the value of detection of DNA of Mycobacterium tuberculosis (MBT) during chemotherapy on an experimental model of an endogenously reactivated tuberculous process. A hundred and fifty BALB/C mice were intravenously inoculated by MBT strain H37Rv and received antituberculous chemotherapy (isoniazid and large-dose pyrazinamide) during 4 and 6 months. Solid medium inoculation, bacterioscopy, cytology, polymerase chain reaction were used to show the value of detection of MBT DNA in the viscera and blood in confirming the development of tuberculosis and testifying the preservation of MBT in the body if the treatment regimen was incomplete, which can lead to endogenous reactivation of the process under certain conditions. Gene typing of MBT, as described in?? of the Russian Federation under IS6110 provided evidence for the endogenous pattern of reactivation. |