Association between tuberculosis recurrence and interferon-γ response during treatment

Summary Objectives We investigated the relationship between tuberculosis recurrence and Mycobacterium tuberculosis antigen-stimulated interferon-gamma (IFN-γ) responses during treatment. Methods Plasma IFN-γ levels in active pulmonary tuberculosis patients ( n  = 407) were analyzed using QuantiFERON-TB Gold In-Tube™ (QFT-IT) at 0, 2, and 7 months of the 8-month treatment received from 2007 to 2009 and the patients were followed up for another 16 months after treatment. Risk factors for recurrence were assessed using the log-rank test and Cox proportional hazard models. Random coefficient models were used to compare longitudinal patterns of IFN-γ levels between groups. Results QFT-IT showed positive results in 95.6%, 86.2%, and 83.5% at 0, 2, and 7 months, respectively. The antigen-stimulated IFN-γ responses varied significantly during the treatment course ( P P Conclusions Although the IGRA response varies individually, early response during the treatment course may provide an insight into host immune responses underlying tuberculosis recurrence.