Abstract
Hydronephrosis causing hypertension was first suspected by Friedriks in 1835. Then, extensive investigations on the renal hypertension accompanied by hydronephrosis were carriedb out clinically and experimentally by many authors. Pediatric cases have been also reported by Abeshouse (1941), Garret (1970), Davis (1973) and Chapman (1975). During the past 5 years we have experienced 9 cases of unilateral congenital hydronephrosis in children younger than 8 years of age. Eight of them revealed hypertension associcated with elevated levels of plasma renin activity (PRA). Renal hypertension has normalized in 6 of them soon after urinary decompression as reported by Garret, Davis and Chapman. Renal biopsy revealed increased production of renin granules in the juxtaglomerular apparatus. These results suggested that the elevated levels of PRA are attributed to increased release of renin from the affected kidney. The urinary decompression failed to reduce the renal hypertension in 2 cases. One patient showed severe damage of the hydronephrotic kidney, although some amounts of JGA necessary for elevation of PRA were probably intact. Another patient had been associated with uncontrollable renovascular hypertension secondary to hydronephrosis. The 2 patients had to inevitably undergo nephrectomy. These clinical observations suggest that renal hypertension accompanied by hydronephrosis reflects varying pathological states of the affected kidneys. Therefore, serial blood pressure and PRA determinations performed before and after the urinary decompression appear to be useful for clinical evaluation of the hydronephrosis. I this paper, pathogenesis of renal hypertension accompanied by hydronephrosis and its clinical significance were discussed in relation to our 9 children.
