Evaluation of Quantiferon TB Gold Test for the Diagnosis of Latent and Active Tuberculosis

Background: Tuberculosis (TB) is a worldwide public health problem. The present study evaluate usefulness of Quantiferon TB Gold (QFT-G) test along with tuberculin skin test (TST) in the diagnosis of TB and to demonstrate the prevalence of latent TB in the study population of high TB prevalence area of Nagpur, India.

Materials and methods: Venous blood sample of 74 study population were collected and QFT-G and TST tests were performed in collected blood samples.

Results: QFT-G was more positive than TST in diagnosing TB infection. The overall specificity of QFT-G & TST was 50% & 64.86% respectively along with 50% discordant results between QFT-G and TST.

Conclusion:

Diagnosis of different tuberculosis along with latent is better by QFT-G as compare to TST except suspected pulmonary TB infection. However, the detection and prevalence (56%) of latent TB infection is much greater when both the tests are combined.