TNF and tuberculosis: According to previous studies on LTBI and TB monitoring during TNF inhibitor therapy, fifteen out of 78 patients (19.2%) with IBD experienced positive conversion of any LTBI tests after a median follow-up of 16 months in Hong Kong (11), and 11.8% of patients with rheumatologic diseases underwent positive IGRA conversion after a median of 12.3 months in South Korea (12).