In vitro drug susceptibility pattern of Mycobacterium tuberculosis in CAT I and CAT II pulmonary tuberculosis patients in Aligarh, Uttar Pradesh, India

ObjectiveTo evaluate in vitro resistance pattern of the first line anti-tubercular drugs in new and previously treated cases of pulmonary tuberculosis patients in Aligarh region.MethodsThis study was carried out involving 975 suspected tuberculosis patients. All the specimens of patients were subjected to Ziehl-Neelsen staining, cultured on Lowenstein-Jensen medium and resistance pattern was evaluated by standard proportion method. All patients diagnosed with pulmonary tuberculosis were placed in CAT I and II under Revised National Tuberculosis Control Programme guidelines.ResultOut of 220 patients, 129 (58.7%) were from CAT I and 91 (41.3%) were from CAT II. Totally 44.5% were resistant to one or more than two drugs and 18.6% patients showed resistance to both isoniazid and rifampicin. The individual resistance pattern of these first line drugs were as follows: 37.7% patients were resistant to isoniazid, 22.2% to rifampicin, 8.6% to streptomycin and 10% were resistant to ethambutol.ConclusionsOur findings concluded a high prevalence of in vitro drug resistance of Mycobacterium tuberculosis isolates, especially multidrug resistant tuberculosis, in both the categories. So there is an urgent need to further study the risk factors for transmission and multidrug resistant tuberculosis in these settings.