Tuberculosis in patients receiving anti-TNF agents despite chemoprophylaxis

Abstract

Setting: A major concern surrounding the use of tumor necrosis factor-alpha (TNF-alpha) inhibitors is their potential to increase the risk of opportunistic infections, particularly tuberculosis (TB).

Objective: To estimate the incidence of active TB in patients with rheumatic diseases receiving anti-TNF drug therapy and to evaluate the effectiveness of an antituberculosis chemoprophylaxis regimen.

Design: Retrospective study of the files of 613 patients with rheumatic diseases who had received anti-TNF agent (etanercept, infliximab and adalimumab) therapy from July 2000 to June 2004 at the Aristotle University of Thessaloniki, Greece. All patients had a tuberculin skin test (TST) and a postero-anterior chest radiograph (CXR) prior to anti-TNF therapy. When indicated (TST > or =10 mm and/or fibrotic lesions on CXR), treatment for latent TB was established (6 months isoniazid [INH] or 3 months INH and rifampicin [RMP]). Anti-TNF agent therapy was started again 2 months later.

Results: Of 45 patients who fulfilled the criteria for chemoprophylaxis, only 36 were treated correctly. Eleven patients developed active TB 2-35 months after the beginning of anti-TNF therapy. Six patients developed pulmonary and five extra-pulmonary TB. Eight of these had received infliximab and three adalimumab.

Conclusion: The incidence of active TB in this study population was estimated at 449 cases per 100,00 population annually. Anti-tuberculosis chemoprophylaxis was only of partial preventive success in these patients.