Low levels of second-line drug resistance among multidrug-resistant Mycobacterium tuberculosis isolates from Rwanda.

Multidrug-resistant tuberculosis (MDR-TB) has become a therapeutic problem in many parts of the world, necessitating the inclusion of second-line anti-tuberculosis drugs in specific treatment regimens.We studied the susceptibility of 69 MDR Mycobacterium tuberculosis isolates from Rwanda to second-line drugs by the BACTEC 460 method.The results showed that 62 (89.9%) were resistant to rifabutin while a low rate (4.3%) of resistance was registered for ofloxacin; there was one case (1.4%) of resistance each for para-aminosalicylic acid, kanamycin, ethionamide, and clarithromycin.This information is important for devising an appropriate treatment regimen for MDR-TB patients in order to stop the spread of MDR strains and contain the acquisition of additional drug resistance in Rwanda.