Malignant Hypertension Cured by Unilateral Nephrectomy.

The classical work of Goldblatt (1934 and 1937) and of Wilson and Byrom (1939), demonstrating the development of hypertension following unilateral renal ischmmia and the return of the blood pressure to normal following removal of the renal lesion, gave a great stimulus to the clinical study of hypertension. As a result it is clear that in man, as in the experimental animal, renal ischemia gives rise to hypertension. If the lesion is confined to one kidney and that kidney is removed before permanent hypertensive changes have developed the hypertension may be cured. Many clinical cases have now been investigated and the commonest cause of unilateral renal disease producing hypertension appears to be chronic atrophic pyelo-nephritis (Braasch, 1942). How this leads to renal ischvmia is not clear but Barker and Walters (1940) have suggested that there may be an obstruction to the renal arteries in these cases. Among other conditions found to produce hypertension have been atherosclerosis of the renal artery, pyonephrosis, renal tuberculosis, neoplasm, and trauma. Apparent cure of the hypertension following removal of the damaged kidney was first reported by Butler (1937) in a case of pyelo-nephritis, and similarly successful results have been reported by others. (Patch, Rhea, and Codnere, 1940; Barker and Walters, 1940; Movin, Ohlsen, and Pedersen, 1944; Powers and Murray, 1942; Platt, 1941, etc.) Successful reports of nephrectomy have also been made in renal tuberculosis (Kennedy, Barker, and Walters, 1941), in tumour (Koons and Ruch, 1941; Richardson and Smart, 1941), following trauma (Farrell and Young, 1942), and in atherosclerosis of the renal artery (Leiper, 1944). However removal of the offending kidney has by no means always resulted in cure of the hypertension and in some cases in which the immediate effects of the operation were gratifying the blood pressure later returned to the same level as before operation. In 1940 Schroeder and Fish analysed reported cases and laid down the following criteria for operation.