Drug-induced Hypersensitivity Syndrome Accompanied by Pulmonary Lesions Exhibiting Centrilobular Nodular Shadows.

A 51-year-old woman diagnosed with Crohn's disease developed drug-induced hypersensitivity syndrome (DIHS) 12 and six weeks after starting the oral intake of mesalazine and trimethoprim/sulfamethoxazole, respectively. Chest CT showed centrilobular nodular shadows and a transbronchial lung biopsy (TBLB) revealed infiltration of inflammatory cells predominantly in the small pulmonary artery walls and bronchiolar walls. Regarding pulmonary lesions of DIHS, infiltrative shadows have sometimes been reported, whereas nodular shadows have rarely been documented. This is a valuable case report for considering the mechanism underlying the development of pulmonary lesions in case of DIHS.