Treatment end point determinants for pulmonary tuberculosis: human resistin as a surrogate biomarker

Treatment of tuberculosis (TB), which takes one human life every 15 s, globally, requires a prolonged (>6 months) antitubercular treatment (ATT) which, is known to have hepatotoxic side effects. This study was designed to explore the utility of human resistin, a proinflammatory hormone, as a sensitive biomarker to determine TB treatment end points. Patients for pulmonary tuberculosis enrolled under the directly observed treatment, short-course (DOTS) program were followed-up for six months and were monitored by sputum analysis, body weight and ELISA-based serum resistin and C-reactive protein (CRP) levels at 0, 2, 4 and 6 months, along with close family contacts of TB patients and healthy controls. The mean circulating resistin levels were found to be significantly higher (P < 0.001) in patients (n = 48, 25.74 ± 9.45 ng/ml) reporting for the first time for treatment (T0) as compared to healthy subjects (n = 45, 7.18 ± 2.40 ng/ml). Resistin levels in contacts (n = 48, 19.61 ± 7.88 ng/ml) also were found to be significantly (P < 0.001) elevated as compared to healthy controls. Significant increase in body weight after four months (P = 0.006) and at 6 months (P < 0.001) of treatment inversely correlated with resistin levels. Our data suggest resistin could be a surrogate marker for TB treatment in addition to its utility as an early prognostic biomarker for monitoring TB disease onset.