P47

Nontuberculous mycobacterial infections caused by Mycobacterium species are increasing worldwide day by day. Despite being a treatable disease, treatment regimens can be prolonged and sometimes fail due to the usage of multiple drugs, natural or acquired resistance, and the inability to differentiate from the Mycobacterium tuberculosis complex. Due to the potential for resistance that may be encountered due to these problems, the discovery of new drugs is of utmost importance. It has been shown in previous studies that bedaquiline, discovered by Koen Andries and colleagues in 2005, is effective against multidrug-resistant M. tuberculosis and nontuberculous mycobacterial strains. Our study aimed to investigate the effect of bedaquiline, which has not yet been introduced in our country, on nontuberculous mycobacterial strains isolated from samples sent for routine examination to the Istanbul University Istanbul Faculty of Medicine Mycobacteriology laboratory and Istanbul Duzen Laboratory. The study included 62 rapid and 41 slow strains from 14 different species. As stated in the guidelines, the microdilution method was applied with a MIC range of 0.008-16 µg/ml. It was determined that all slow-growing strains may be sensitive to bedaquiline (MIC ≤0.25µg/ml), while 16 of the rapid-growing strains may be resistant (MIC >0.25µg/ml). Of the potentially resistant strains, seven were identified as M. fortuitum, five as M. abscessus, three as M. chelonae, and one as M. elephantis. In conclusion, it was observed that bedaquiline has a high activity against nontuberculous mycobacterial strains.