Tubular stenosis of the aorta with aortic fibromuscular dysplasia.

The autopsy findings in a 2-year-old girl with severe hypertension resulting from stenosis of the lower part of the thoracic and the abdominal aorta were reviewed. The lower portion of the thoracic aorta and the abdominal aorta showed uniform narrowing down to the level of the bifurcation of iliac arteries. Histologically, the aortic wall of the stenotic site showed irregular proliferation of smooth muscle cells and collagen fibers. The elastic fibers had disappeared from outside the media. No intimal thickening and inflammatory cell infiltration were observed. These histologic changes of the aortic media in this case are apparently similar to fibromuscular dysplasia (medial hyperplasia).