[A case of classical polyarteritis nodosa diagnosed by myocardial biopsy].

We experienced a girl with polyarteritis nodosa (PN) diagnosed by myocardial biopsy. The symptoms began with high fever and skin rash. These symptoms and laboratory findings temporarily improved by oral prednisolone, however, she flared up with chest pain about 40 days after onset of the disease. Electrocardiogram indicated the elevation of ST-T levels and low voltage, and blood examination showed remarkable elevation of creatine phosphokinase (CK), white blood cell count (WBC), aspartate aminotransferase (AST) and lactic dehydrogenase (LDH) levels. We suspected systemic vasculitis and damage of coronary artery or/and heart muscle. Finally, she was diagnosed with classical polyarteritis nodosa by myocardial biopsy. Coronary angiography revealed no abnormalities. The combination therapy of cyclophosphamide pulses and plasma-exchange was very effective to suppress the disease activity.