Mesalazine-induced airway obstruction: Utility of pulmonary function testing in drug-induced lung diseases

Mesalazine is a standard therapeutic agent for the treatment of inflammatory bowel diseases. A rare case of mesalazine-induced airway obstruction documented by pulmonary function testing is reported herein. The patient had Crohn's disease and was treated with mesalazine; she subsequently developed a high fever, cough, and chest pain with centrilobular nodular shadows on chest computed tomography (CT). After cessation of mesalazine, the abnormal CT findings as well as the decreased forced expiratory volume in 1 second improved. Based on these findings, pulmonary function testing appears to be a useful tool, even in the acute phase, along with chest CT in drug-induced lung diseases.