Histological and ultrastructural features of atherosclerosis in progeria.

This histological and ultrastructural study of a limited amount of vascular tissue from a progeric woman of 20 years who died of traumatic subdural hemorrhage supports the belief that the vascular changes are atherosclerotic. The unusual features observed were collagen fibrils with a relatively small diameter in the atherosclerotic intima and media, extensive loss of mural smooth muscle cells particularly in the aorta, and widespread contraction bands in smooth muscle cells in vascular and nonvascular tissues. Smooth muscle cells appear to be unusually susceptible to hemodynamic and ischemic stress. Further autopsy studies are required to elucidate the etiology and pathogenesis of this unique disease.