Adalimumab-induced interstitial pneumonia with an improvement of pre-existing rheumatoid arthritis-associated lung involvement.

A 78-year-old man with an 18-year history of rheumatoid arthritis (RA) was treated with tumor necrosis factor (TNF)-α inhibitor adalimumab. Chest computed tomography showed a previously detected consolidation. The patient's arthritic symptoms substantially decreased with the initiation of adalimumab, with a simultaneous improvement of the lung lesion. However, additional interstitial pneumonia was found a month after starting adalimumab. This course suggested that adalimumab might be effective against RA-associated lung disease, but may also have caused drug-induced interstitial pneumonia. This is the first report indicating that TNF-α inhibitor shows simultaneously conflicting actions in a patient with RA-related lung disease.