Authors' reply.

Sir,

We would like to thank Dr. Lai in his letter.[1] He mentioned that we failed to describe patient's characteristics in all aspects and also did not show us the results of all the methodology used. We would like to mention that the paper Jung JY et al.[2] addressed in the letter found that the IGRA sensitivity and specificity (95% CI) were: QFT-GIT (59.0% (44.9-72.0)) and (61.3% (54.4-67.6)) and T-SPOT.TB (72.0% (54.2-86.2)) and (42.3% (33.8-4 9.1)), respectively. For TST, the sensitivity was 41.2% (28.3-50.8) and specificity was 91.8% (85.8-96.30). The sensitivities of the three diagnostic methods tended to be lower in the immunosuppressive drug group than in other groups (QFT-GIT 11.1%, T-SPOT.TB 40.0%, and TST 25.0% in patients with taking immunosuppressive drugs). Lai et al.[3] found that T-SPOT.TB had a higher sensitivity and resulted in fewer indeterminate results than the QFT-GIT assay for diagnosing active TB.