Abstract
Two cases of severe fibromuscular dysplasia of the renal arteries are described in which the diagnosis was made 12 and 11 years after renal angiography had shown the arteries to be normal. The discovery of hypertension preceded the diagnosis by two and 11 years respectively, and in one case hypertension was present at the time of the normal renal angiogram. The report suggests that fibromuscular dysplasia of the renal arteries is acquired and may not be present from birth. The importance of regular review in cases of severe hypertension is emphasised.