Anti-NMDAR encephalitis in a patient with Crohn disease receiving adalimumab.

Anti–tumor necrosis factor alpha (TNF-α) therapies have been a significant advance in the treatment of autoimmune and rheumatologic diseases. Early preclinical and clinical studies of anti–TNF-α therapies emphasized infection and malignancy as serious adverse events associated with these agents.1 However, subsequent clinical experience has increasingly recognized a rare and seemingly paradoxical risk of autoimmunity with agents targeting the TNF-α pathway, most notably psoriatic eruptions,2 but also autoimmune processes associated with autoantibody production, including systemic vasculitis and lupus erythematosus.3,4 The development of neurologic diseases in association with anti–TNF-α therapy has been documented in case series and small prospective studies,5 with the most commonly reported associations being demyelinating diseases of the CNS and peripheral nervous systems. Here, we report a patient who developed anti–NMDA receptor (NMDAR) encephalitis while being treated with adalimumab for Crohn disease.