Acute exacerbation of preexisting interstitial lung disease after administration of etanercept for rheumatoid arthritis.

A 70-year-old woman with a 6-year history of seropositive rheumatoid arthritis (RA) and asymptomatic interstitial lung disease (ILD) began taking etanercept for ongoing arthritis despite treatment with methotrexate (MTX) and bucillamine. MTX was discontinued before introduction of etanercept. She developed lung injury 8 weeks after starting etanercept. Etanercept was discontinued and oral prednisolone 40 mg/day was begun, and her clinical findings gradually improved. Lung injury, although rare, is a recently noticed, potentially fatal adverse effect of all 3 licensed biological anti-tumor necrosis factor (TNF) agents. We recommend caution in the use of anti-TNF agents in elderly RA patients with preexisting ILD.