Polymyositis associated with dissecting aneurysm of arteries and intracerebral hemorrhage.

Dissecting aneurysm and stroke are a rare complication of polymyositis. The present report describes an autopsy case of a 53-year-old woman, who suffered from polymyositis accompanied by dissecting aneurysms of right external iliac and right renal arteries, and furthermore, intracerebral hemorrhage. The latter was caused by necrotizing angiitis. The patient had no abnormal anatomical changes such as coarctation of aorta, aortic stenosis, bicuspid aortic valve or Marfan's syndrome. Atherosclerosis in the patient was mild, and cystic medial necrosis of aorta and arteries was not found. Since the patient was attacked by dissections of arteries following long-term steroid therapy, a possibility can be raised that arterial dissection was attributable to steroid treatment besides necrotizing angiitis complicating in polymyositis.