Drug susceptibility profile of Mycobacterium tuberculosis isolated from HIV infected and uninfected pulmonary tuberculosis patients in Eastern India

HIV is driving the tuberculosis (TB) epidemic in many developing countries including India. This study was initiated to determine the drug resistance pattern of pulmonary TB among 200 HIV seropositive and 50 HIV negative hospitalized patients from different states of Eastern India. The TB positive isolates (120) were screened and characterized by conventional laboratory methods followed by first- and second-line drug susceptibility testing on Lowenstein-Jensen medium by the proportion method. The drug susceptibility testing showed 17.7% (16/90) and 6.6% (2/30) multidrug-resistant (MDR) TB for the HIV positive and HIV negative patients, respectively. 22.2% (4/18) of the isolated MDR-TB cases could be classified as extensively drug-resistant (XDR) TB isolates. 88.8% (16/18) of all the MDR-TB isolates and all XDR-TB isolates were screened from HIV patients. Five (27.7%) of the 18 MDR-TB isolates showed resistance to all the first-line drugs. Mortality rate among the XDR-TB isolates was as high as 75% (3/4). Patients with interrupted anti-TB drug treatment were the ones most affected. These findings are critical and the risk to public health is high, particularly with HIV infected patients.