Resistance pattern of Mycobacterium tuberculosis Complex Isolated from Re-treatment Patients to First Line Anti-Tuberculosis Drugs in Zaria Nigeria

Tuberculosis (TB) is one of the leading infections that cause death worldwide. The emergence of drug-resistant Mycobacterium tuberculosis is of great concern for National TB control programmes wich hinders the control of tuberculosis; therefore it has become important to screen infected patients for resistant TB. A total of 437 sputum samples were collected from re-treatment TB patients. The samples were screened for Acid Fast Bacilli (AFB) and positive samples were cultured on Lowenstein Jensen medium. The isolates were confirmed as Mycobacterium tuberculosis Complex (MTBC) using immune- chromatographic test and their resistant pattern was detected using proportion method. The results revealed that 72 (16.47%) of the samples were AFB Smear positive, out of which, 62 (86%) were culture positive, 6 (8%) were culture negative and 4(6%) were contaminated. Also 57 (91.9%) of the 62 cultures positive samples, were Mycobacterium tuberculosis Complex (MTBC). Among the57 isolates, 33(58%) isolates were found to be resistant to streptomycin, 47 (82.5%) and 44(77%) were found be resistant to isoniazid and rifampicin respectively. While 35 (51%) isolates were found to be resistant to ethambutol. Additionally, 41(71.93%) of the isolates were identified as multi-drug resistant tuberculosis (MDR-TB). The study detects high resistance of M. tuberculosis to the two of the most important first anti-TB drugs as well as exhibited high multidrug resistance. The study identifies the need for fast and accurate diagnosis of resistant TB especially among re-treatment cases to interrupt transmission chain which will go a long way in providing a successful TB control.