Drug susceptibility profile of Mycobacterium kansasii clinical isolates from Brazil

Abstract Objectives M. kansasii pulmonary infection can cause disease with clinical and radiological features similar to tuberculosis. Failure to treat M. kansasii infection is usually associated with resistance, making identification of species and knowledge of the susceptibility profile necessary to increase the chance of successful treatment. The aim of this study was to evaluate the antimycobacterial susceptibility profiles of M. kansasii isolates from Brazil. Methods Sixty nine M. kansasii isolates from 69 patients were identified by partial sequencing of the hsp65 gene and had their susceptibility profiles analyzed by minimal inhibitory concentration (MIC) assays. Results From 69 isolates, 68 showed susceptibility to clarithromycin, amikacin, and moxifloxacin. Most strains showed high rates of resistance to trimethoprim-sulfamethoxazole and ciprofloxacin. Resistance to rifampicin and ethambutol was found (in 12% and 25% of isolates, respectively). Conclusions We have observed worrying results regarding susceptibility to some drugs used as first-line agents in the treatment of diseases caused by M. kansasii .