Isolated central nervous system arteriopathy with multiple aneurysms in an adolescent. A case report.

A 17-year-old male suffered recurrent subarachnoid hemorrhages due to multiple aneurysms in the distal branches of the cerebral arteries. Autopsy revealed arteriopathy as well as the aneurysms. The arteriopathy was widespread, affecting the distal branches of small and medium-sized muscular cerebral arteries, as well as the anterior and posterior spinal arteries, and vasocorona. The arteriopathy was characterized by prominent intimal thickening, discontinuity or absence of the internal elastic lamina, and thinning and/or disappearance of smooth muscle in the tunica media with fibroplasia. Slight intimal thickening was also observed in the arteries of the circle of Willis and its major branches, as well as in the basilar artery. However, the arterioles, venules and veins showed no remarkable features. The arterial lesions were found only in the central nervous system. The multiple aneurysms in the distal branches of the cerebral arteries, which had produced the main symptoms and clinical signs, were due to the arteriopathy.