Investigation of Anti-tuberculous Drug Sensitivity Results in Sixty-one Extrapulmonary Samples Using the MGIT Method

Aim: The aim of this study was to evaluate the susceptibility of Mycobacterium tuberculosis complex (MTBC) strains produced in non-pulmonary samples against major tuberculosis (TBc) drugs, including isoniazid (INH), rifampin (RIF), streptomycin (SM), and ethambutol (EMB), using the Mycobacterium Growth Indicator Tube (MGIT) method. Methods: In this retrospective, cross-sectional study, samples taken from non-pulmonary organs between January 2008 and September 2013 were cultivated in the MGIT, on Lowenstein-Jensen (LJ) media and MTBC isolates identified by Becton Dickinson (BD) MGIT TBc Identification test (TBc ID) were investigated in terms of susceptibility against TBc drugs including INH, RIF, SM and EMB by BACTEC MGIT 960 (Becton Dickinson, USA). Results: In our study, MTBC was isolated in 275 (4.6%) of 6018 samples that were incubated in MGIT and LJ media. Of 275 MTBC isolates, 160 (58%) belonged to non-pulmonary organs and 115 (42%) to the lung. While a resistance to those anti-tuberculosis drugs was not detected in 41 (67.2%), the resistance rates were 27.8% for INH, 3.2% for RIF, 14.7% for EMB, and 11.5% for SM. Conclusions: The rate of resistance to INH + RIF detected in the MTBC isolates cultured from extrapulmonary samples was found to be similar to those reported in other studies from Turkey. The high rate of resistance to INH should be taken into consideration in the treatment and management of TBc.