Jennifer A Tash1, Jeffrey A Stock, Moneer K Hanna. 1. James Buchanan Brady Urology Foundation, Department of Urology, New York Presbyterian Hospital-Weill Medical College of Cornell University, New York, New York, USA.
Abstract
PURPOSE: From 5% to 25% of hypertension in children is renovascular compared with only 1% in adults. Although much attention is given to renovascular disease involving the main renal arteries, renin producing renal disease may also be intrarenal, involving abnormalities of the segmental vessels or renal parenchyma. We present our results of partial nephrectomy in this unique group of pediatric patients with hypertension in whom renin dependent hypertension involved only a segment of the kidney. MATERIALS AND METHODS: Six patients 10 months to 16 years old were referred for the evaluation of hypertension. Initial evaluations included computerized tomography, ultrasound, voiding cystourethrography and radionuclide renal scan. Renal arteriography with renal vein renin sampling was performed in 5 patients, of whom 4 underwent selective segmental renal vein sampling. Diagnoses included segmental hypoplasia (Ask-Upmark kidney), reflux associated scarring and renal arteriovenous malformation. RESULTS: In patients who underwent selective segmental renal vein sampling an increased renin level was present in the area of the renal lesion (mean 24.9 ng./ml. per hour, range 9.2 to 40.6) compared to the ipsilateral renal vein (15.6, 114 to 29.8). Three patients had evidence of contralateral suppression of renin secretion. All 6 patients underwent upper, lower or mid segment partial nephrectomy. All patients became immediately normotensive and remained so at a mean 10 years of followup. CONCLUSIONS: Partial nephrectomy provides an excellent nephron sparing cure for segmental renal hypertension. In the pediatric population selective segmental renal vein renin sampling is invaluable for locating the renin producing lesion. As in adults, contralateral renin suppression is predictive of surgical cure.
PURPOSE: From 5% to 25% of hypertension in children is renovascular compared with only 1% in adults. Although much attention is given to renovascular disease involving the main renal arteries, renin producing renal disease may also be intrarenal, involving abnormalities of the segmental vessels or renal parenchyma. We present our results of partial nephrectomy in this unique group of pediatric patients with hypertension in whom renin dependent hypertension involved only a segment of the kidney. MATERIALS AND METHODS: Six patients 10 months to 16 years old were referred for the evaluation of hypertension. Initial evaluations included computerized tomography, ultrasound, voiding cystourethrography and radionuclide renal scan. Renal arteriography with renal vein renin sampling was performed in 5 patients, of whom 4 underwent selective segmental renal vein sampling. Diagnoses included segmental hypoplasia (Ask-Upmark kidney), reflux associated scarring and renal arteriovenous malformation. RESULTS: In patients who underwent selective segmental renal vein sampling an increased renin level was present in the area of the renal lesion (mean 24.9 ng./ml. per hour, range 9.2 to 40.6) compared to the ipsilateral renal vein (15.6, 114 to 29.8). Three patients had evidence of contralateral suppression of renin secretion. All 6 patients underwent upper, lower or mid segment partial nephrectomy. All patients became immediately normotensive and remained so at a mean 10 years of followup. CONCLUSIONS: Partial nephrectomy provides an excellent nephron sparing cure for segmental renal hypertension. In the pediatric population selective segmental renal vein renin sampling is invaluable for locating the renin producing lesion. As in adults, contralateral renin suppression is predictive of surgical cure.