Comparison of Sensitivity of QuantiFERON-TB Gold Test and Tuberculin Skin Test in Active Pulmonary Tuberculosis

Objective: To compare the sensitivity of tuberculin skin test (TST) and quantiFERON-TB gold test (QFT-G) in active pulmonary tuberculosis. Study Design: Analytical study. Place and Duration of Study: Department of Pulmonology, Fauji Foundation Hospital, Rawalpindi, from July 2011 to January 2012. Methodology: QuantiFERON-TB gold test (QFT-G) was evaluated and compared it with tuberculin skin test (TST) in 50 cases of active pulmonary tuberculosis, in whom tuberculous infection was suspected on clinical, radiological and microbiological grounds. Sensitivity was determined against postive growth for Mycobacterium tuberculosis. Results: Out of 50 cases, 43 were females and 7 were males. The mean age was 41.84 +/- 19.03 years. Sensitivity of QFT-G was 80% While that of TST was 28%. Conclusion: QFT-G has much higher sensitivity than TST for active pulmonary tuberculosis. It is unaffected by prior BOG administration and prior exposure to atypical mycobacteria. A positive QFT-G result can be an adjunct to diagnosis in patients having clinical and radiological data compatible with pulmonary tuberculosis.