Susceptibilities of Mycobacterium tuberculosis Complex Isolates to First-line Antituberculosis Drugs at Dokuz Eylül University Hospital

Objective: Tuberculosis retains its importance as the only infectious disease in the world that affects 10 million people and causes 1.5 million deaths per se. The major obstacle in the elimination and control of tuberculosis is the emergence and spread of resistant tuberculosis cases. It was aimed to determine the current Mycobacterium tuberculosis complex and its susceptibility to antituberculosis drugs at Dokuz Eylül University Hospital. Method: In our study, the results of all samples sent between January 2013 and November 2019 were examined retrospectively for the presence of M. tuberculosis complex and drug susceptibility results. The samples were cultured in Löwenstein Jensen media and BACTEC MGIT 960 system. Drug susceptibility testing was performed with the BACTEC MGIT 960 SIRE kit in accordance with the recommendations of the manufacturer. Results: In a total of 473 (2.2%) of 21620 specimens M. tuberculosis complex was reproduced. The samples were classified as pulmonary (n:300; 63.4%) and extrapulmonary (n:173; 36.6%), samples. When repeated samples of the same patient, were excluded, positive culture test results were determined in a total of 365 patients. Susceptibility to all primary antituberculosis drugs was shown in 275 of 321 (85.7%) patients, while total rates of resistance to streptomycin, isoniazid, rifampicin and ethambutol were found in respective number of patients as follows: (n:24 (7.5%), 22 (6.8%), (n:7; 2.2%) and (n:2; 0.6%). The rate of MDR was 0.6% in 2 patients. Conclusion: In our hospital, streptomycin is the first-line antituberculosis drug with the highest resistance rate. All susceptibility rates were seen lower than the data reported in Turkey Tuberculosis Control Report and other studies of Turkey. Implementing drug surveillance program plays an important role for maintaining these low rates and for the management of tuberculosis.