Autoimmune diseases induced by TNF-targeted therapies: analysis of 233 cases

Tumor necrosis factor (TNF)-targeted therapies are increasingly used for a rapidly expanding number of rheumatic and autoimmune diseases. With this use and longer follow-up periods of treatment, there are a growing number of reports of the development of autoimmune processes related to anti-TNF agents. We have analyzed the clinical characteristics, outcomes, and patterns of association with the different anti-TNF agents used in all reports of autoimmune diseases developing after TNF-targeted therapy found through a MEDLINE search of articles published between January 1990 and December 2006. We identified 233 cases of autoimmune diseases (vasculitis in 113, lupus in 92, interstitial lung diseases in 24, and other diseases in 4) secondary to TNF-targeted therapies in 226 patients. The anti-TNF agents were administered for rheumatoid arthritis (RA) in 187 (83%) patients, Crohn disease in 17, ankylosing spondylitis in 7, psoriatic arthritis in 6, juvenile RA in 5, and other diseases in 3. The anti-TNF agents administered were infliximab in 105 patients, etanercept in 96, adalimumab in 21, and other anti-TNF agents in 3. We found 92 reported cases of lupus following anti-TNF therapy (infliximab in 40 cases, etanercept in 37, and adalimumab in 15). Nearly half the cases fulfilled 4 or more classification criteria for systemic lupus erythematosus (SLE), which fell to one-third after discarding preexisting lupus-like features. One hundred thirteen patients developed vasculitis after receiving anti-TNF agents (etanercept in 59 cases, infliximab in 47, adalimumab in 5, and other agents in 2). Leukocytoclastic vasculitis was the most frequent type of vasculitis, and purpura was the most frequent cutaneous lesion. A significant finding was that one-quarter of patients with vasculitis related to anti-TNF agents had extracutaneous involvement. Twenty-four cases of interstitial lung disease associated with the use of anti-TNF agents were reported. In these patients, 2 specific characteristics should be highlighted: the poor prognosis in spite of cessation of anti-TNF therapy, and the possible adjuvant role of concomitant methotrexate. In conclusion, the use of anti-TNF agents has been associated with an increasing number of cases of autoimmune diseases, principally cutaneous vasculitis, lupus-like syndrome, SLE, and interstitial lung disease.