Unilateral methotrexate-induced lung injury with foreign bodies in the airway: A case report

A 75-year-old woman who had been taking methotrexate presented to our hospital for fever and dry cough. Chest computed tomography showed ground-glass opacity in the upper lobe of the right lung and foreign bodies in the lower lobe of the right bronchus. During bronchoscopy, foreign bodies were removed from the airway. We found increased levels of lymphocytes and a high CD4/CD8 ratio in the bronchoalveolar lavage fluid. Transbronchial lung biopsy revealed lymphocytic infiltration. Methotrexate was discontinued, and the imaging findings improved. Methotrexate-induced lung injury does occur unilaterally. Foreign bodies in the airway might also trigger unilateral methotrexate-induced lung injury.