Pulmonary complications of methotrexate therapy.

Diffuse interstitial pulmonary infiltration was first reported in 1969, occurring during intermittent methotrexate therapy and it is suggested that it represents an adverse reaction to this drug. Despite the severity of the clinical and radiological changes, the disease is usually self-limiting. An additional case is presented and the previous 28 reported cases of this syndrome are summarized. Since intermittent methotrexate therapy is becoming more widely used, the importance of recognizing this respiratory illness as a possible complicating reaction to the drug is stressed.