Radiographic appearance of bronchiolitis obliterans organizing pneumonia (BOOP) developing during bucillamine treatment for rheumatoid arthritis

Bucillamine, a disease-modifying antirheumatic drug, can have adverse effects, including lung injury. Development of interstitial pneumonia during treatment for patients with rheumatoid arthritis (RA) can pose a difficult differential diagnosis between a direct manifestation of RA and a drug effect. Our review of previous reports suggested bucillamine-induced interstitial pneumonia in the patient described here, visualized by chest radiography and computed tomography based on patchy ground-glass opacities in a peribronchial or peripheral distribution, suggesting the appearance of bronchiolitis obliterans organizing pneumonia (BOOP). As is typical for BOOP, steroid responsiveness may have contributed to recovery.