An 82-yr-old man was presented with fever and cough accompanied by generalized erythematous rash. He had taken mexiletine for 5 months, as he had been diagnosed with dilated cardiomyopathy and ventricular arrhythmia. Laboratory studies showed peripheral blood eosinophilia and elevated liver transaminase levels. Chest radiographs showed multiple nodular consolidations in both lungs. Biopsies of the lung and skin lesions revealed eosinophilic infiltration. After a thorough review of his medication history, mexiletine was suspected as the etiologic agent. After discontinuing the mexiletine and starting oral prednisolone, the patient improved, and the skin and lung lesions disappeared. Subsequently, mexiletine was confirmed as the causative agent based on a positive patch test. Drug-induced hypersensitivity syndrome is a severe adverse reaction to drugs and results from treatment with anticonvulsants, allopurinol, sulfonamides, and many other drugs. Several cases of mexiletine-induced hypersensitivity syndrome have been reported in older Japanese males with manifestation of fever, rash, peripheral blood eosinophilia, liver dysfunction without other organ involvement. Here, we report a case of mexiletine-induced hypersensitivity syndrome which presented as eosinophilic pneumonia in a Korean male.
Aged, 80 and over ; Anti-Arrhythmia Agents/*adverse effects ; Arrhythmias, Cardiac/drug therapy ; Cardiomyopathy, Dilated/drug therapy ; Drug Hypersensitivity/*diagnosis/etiology ; Exanthema/pathology ; Humans ; Lung/pathology/radiography ; Male ; Mexiletine/*adverse effects ; Pulmonary Eosinophilia/*chemically induced/*diagnosis ; Syndrome ; Tomography, X-Ray Computed

Mesalazine (5-aminosalicylic acid) and sulfasalazine are widely used in the treatment of inflammatory bowel disease. The pulmonary toxicity related to sulfasalazine was well-recognized complication and it was caused by sulfapyridine moiety in sulfasalazine. However, the lung injury related to mesalazine has rarely been reported. A thirty five-year-old man with Crohn's disease who was treated with mesalazine complained fever and dry cough. The finding of bilateral wandering pulmonary infiltration, peripheral eosinophilia and increased eosinophils in bronchoalvolar lavage were consistent with eosinophilic pneumonia. His symptoms and laboratory findings were markedly improved after the discontinuation of mesalazine. The mesalazine-induced eosinophilic pneumonia was diagnosed according to his clinical course. This report shows that the eosinophilic pneumonia should be considered in patients who develope pulmonary involvement with inflammatory bowel disease receiving mesalazine therapy.
Adult ; Anti-Inflammatory Agents, Non-Steroidal/*adverse effects/therapeutic use ; Crohn Disease/*drug therapy ; Humans ; Lymphocyte Activation ; Male ; Mesalamine/*adverse effects/therapeutic use ; Pulmonary Eosinophilia/chemically induced/*diagnosis/radiography ; Tomography, X-Ray Computed