A case of aprindine-induced pneumonitis

A 73-year-old man had been treated with Aprindine because of paroxysmal atrial fibrillation. On July 13, 1987, five months after the commencement of aprindine administration, he developed dyspnea and low grade fever. His chest X-ray revealed multiple infiltrative shadows in both lung fields. He was treated by various antibiotics, but the infiltrative shadows increased. BALF showed increased percentage of lymphocytes and a decrease in the OKT4/T8 ratio, and the histological findings of TBLB carried out on August 6, 1987, showed alveolitis with Masson bodies. The lymphocyte stimulation test by drugs was positive only for aprindine. After cessation of Aprindine administration, his complaints and laboratory data improved, but his abnormal shadow on chest X-ray did not diminish completely. Open lung biopsy was performed for differential diagnosis of BOOP, on Sep. 14, 1987. The histopathology of specimens of the lung was compatible with drug-induced pneumonitis. The administration of 30 mg of prednisolone was started on Oct. 14, 1987, and the dosage was decreased gradually. The abnormal shadow on chest X-ray improved. To our knowledge, there has been no reported case of Aprindine-induced pneumonitis, and this could be the first report.