Drug susceptibility pattern of Mycobacterium tuberculosis isolated from new cases of pulmonary tuberculosis at a tertiary care hospital of eastern Nepal

Introduction Multi drug resistant tuberculosis (TB) possesses a serious threat for the control of the tuberculosis. The objective of this study were to observe the drug susceptibility patterns of Mycobacterium tuberculosis isolated from newly diagnosed cases of pulmonary tuberculosis and determine the prevalence of drug resistant tuberculosis in eastern Nepal. Methods A cross sectional study was conducted in Department of Microbiology, B.P Koirala Institute of Health Sciences, Dharan, Nepal. A total of 58 smear positive sputum samples were processed for culture in Lowenstein Jensen media and drug susceptibility testing was performed by conventional proportion method using standard protocol. The Chi square test was used and p value <0.05 was considered statistically significant. Results Among the 58 patients enrolled in the study, the mean age of the patients was 40.7 years with male preponderance of 70.7%. The prevalence of drug resistant TB among culture positive pulmonary TB cases was 23.1% and the rate of multidrug resistant TB was found to be 5.8% in our study. The highest rate of resistance of mycobacterium tuberculosis was towards isoniazid 15.4% followed by rifampicin 13.5%. Conclusions The high prevalence of drug resistant TB in our study reflects the improper implementation of tuberculosis control programme in Nepal. Therefore, it emphasizes the need for molecular method for TB diagnosis and effective TB control program in the country. Keywords: Drug susceptibility testing, Isoniazid, Pulmonary tuberculosis, Rifampicin