Nonasthmatic eosinophilic bronchitis in an ulcerative colitis patient – a putative adverse reaction to mesalazine: A case report and review of literature

BACKGROUND: Lung and airway involvement in inflammatory bowel disease are increasingly frequently reported either as an extraintestinal manifestation or as an adverse effect of therapy. CASE SUMMARY: We report a case of a patient with ulcerative colitis controlled under mesalazine treatment who presented with chronic cough and hemoptysis. Chest computed tomography and bronchoscopy findings supported tracheal involvement in ulcerative colitis; pathology examination demonstrated an unusual eosinophil-rich inflammatory pattern, and together with clinical data, a nonasthmatic eosinophilic bronchitis diagnosis was formulated. Full recovery was observed within days of mesalazine discontinuation. CONCLUSION: Mesalazine-induced eosinophilic respiratory disorders have been previously reported, generally involving the lung parenchyma. To the best of our knowledge, this is the first report of mesalamine-induced eosinophilic involvement in the upper airway.