Bilateral renal infarction in a black man with medial fibromuscular dysplasia.

We report a case of bilateral renal infarction in a patient with medial fibrous dysplasia of both renal arteries and a thrombosed aneurysmal dilatation of the right renal artery. A previously healthy 40-year-old black man presented to the emergency department with acute onset of bilateral flank pain. Computerized tomography of the abdomen showed bilateral renal infarction, predominantly affecting the anterior distribution of both renal arteries. Estimated loss of renal mass was 50% on the right and 25% on the left. The patient was treated with intravenous heparin, oral warfarin, and antihypertensive therapy with labetolol and long-acting nifedipine. By day 3, his abdominal pain resolved; however, the serum creatinine level increased to a maximum value of 2.6 mg/dL. The serum creatinine level slowly improved and stabilized at 1.9 mg/dL, and he was subsequently discharged on the seventh hospital day. Magnetic resonance angiography performed 2 months later showed "beading2 of both renal arteries consistent with medial fibromuscular dysplasia, a finding confirmed by conventional angiography. To our knowledge, bilateral renal infarction complicating medial fibrous dysplasia of the renal arteries has not been previously reported, nor has medial fibrous dysplasia been reported in blacks.