Tuberculosis in patients receiving anti-TNF agents despite chemoprophylaxis.

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.