Drug-resistant pulmonary tuberculosis in western Turkey: prevalence, clinical characteristics and treatment outcome

BACKGROUND: Although high antituberculosis (anti-TB) drug resistance rates have been reported in Turkey, the clinical characteristics and implications for the outcome of anti-TB treatment have not been fully investigated. We determined the prevalence of anti-TB drug resistance and examined demographic data, clinical characteristics and treatment outcome in relation to patterns of resistance. METHODS: From the TB case registry of a university hospital and the two largest dispensaries in Manisa city, we identified all pulmonary TB cases with a culture-proven definitive diagnosis and antimicrobial susceptibility results for a 7-year period. We collected and analyzed demographic and clinical data and information on treatment outcome for those cases in relationship to anti-TB drug resistance. RESULTS: Of 355 M. tuberculosis strains, 71.5% were susceptible to streptomycin, isoniazid, rifampicin and ethambutol. Any drug resistance and multi-drug resistance (MDR ) rates were 21.1% and 7.3% and were higher in males (53% and 9%, respectively) than in females (22% and 1%, respectively). Drug resistance was significantly higher in old cases (acquired drug resistance) vs new cases (primary drug resistance), and was associated with treatment failure (P<0.001). The prevalence of MDR was significantly higher in the old cases (22.4%) than in the new cases (4.4%) (P<0.001). Symptoms, radiographic findings, associated diseases, and sputum smear positivity were unrelated to the development of resistance. The prevalence of any drug resistance and MDR was significantly higher in those with treatment failure than in patients with treatment success. CONCLUSION: High resistance rates, particularly for acquired MDR, indicate a need for improvement in the TB control programme in our region.