[A case of eosinophilic pneumonia possibly associated with 5-aminosalicylic acid (5-ASA)].

A 30-year-old man was diagnosed as having ulcerative colitis and was treated with 2,250 mg/day of 5-aminosalicylic acid (5-ASA). After 4 weeks of the administration, the patient complained of cough and fever and was admitted to our hospital. His chest radiograph showed infiltrative shadows bilaterally in the lung fields. Peripheral blood analysis indicated eosinophilia. We confirmed eosinophilic pneumonia by bronchoalveolar lavage and transbronchial lung biopsy. Improvement in clinical symptoms and radiological findings was obtained after the cessation of 5-ASA and initiation of prednisolone. Finally, mesalazine-induced eosinophilic pneumonia was diagnosed on the basis of his clinical course. The literature contains a few reports on patients with mesalazine-induced eosinophilic pneumonia.