Incidence of tuberculosis among anti-tumor necrosis factor users in patients with a previous history of tuberculosis

SummaryBackgroundWe aimed to investigate the results of anti-tumor necrosis factor (TNF) therapy in patients with a previous history of tuberculosis (TB).MethodsA total of 101 patients with a previous history of TB receiving TNF antagonists between December 2004 and September 2012 at the Asan Medical Center in South Korea were retrospectively analyzed.ResultsThe mean age of the 101 subjects was 40.4 ± 16.0 years and 51 patients (50.5%) were male. The underlying immune-mediated inflammatory diseases (IMIDs) were Crohn's disease in 55 (54.5%), rheumatoid arthritis in 27 (26.7%), and ankylosing spondylitis in 13 (12.9%) patients. Chest radiography findings were suggestive of previous TB lesions in 33 (32.7%) patients. The rates of positivity in the tuberculin skin test and interferon-gamma release assay were 21.8% (22/101) and 44.6% (45/101), respectively. Latent TB infection (LTBI) treatment was initiated in 11 subjects (10.9%) based on previous inappropriate anti-TB treatments (n = 10) or recent TB contact history (n = 1), irrespective of the LTBI test results. The median follow-up duration after the initiation of TNF antagonist therapy was 31.5 months. Active TB developed, six years after the initiation of TNF antagonist, in one patient (1.0%) who had not received LTBI treatment. The incidence rate of TB was calculated at 336 per 100,000 person-year (PY).ConclusionsPatients with IMIDs who have a previous history of TB can be treated with TNF antagonists with an acceptable incidence of TB, if LTBI treatment is performed based on clinical judgments including the adequacy of previous anti-TB treatment and recent contact history.