Hypertension due to Ask-Upmark kidney

A young girl in whom severe hypertension was cured by the surgical removal of a unilateral hypoplastic kidney (Ask-Upmark kidney) is described. The clinicopathological features of the Ask-Upmark kidney are described with particular reference to the aetiology of the hypertension as well as the selection of patients for surgery. No abnormality of the renin-angiotensin system was detected.