Evaluation of renal function in children with moderate or severe hydronephrosis after operation

Objective To evaluate postoperative renal function in children with congenital moderate or severe hydronephrosis. Methods Tc-99m-labeled diethylenetriaminepenta-acetic acid scintigraphy was performed in 50 children with unilateral moderate or severe hydronephrosis to determine postoperative renal function. We also analyzed the factors influencing renal function recovery. Results Average postoperative renal function in 50 cases was 40.62%+/-10.09%. Among them, 32% of patients had nearly normal renal function and differentiated renal function reached up to 45%. Average preoperative and postoperative renal function in 25 cases was 23.89%+/-11.65% and 39.33%+/-8.59% respectively and the increase of renal function was about 15.44%+/-11.18% (P=0.0003). Renal parenchyma thickness was negatively correlated with postoperative renal function (r=-0.62, P=0.0009). The follow-up period was positively correlated with postoperative renal function (r=0.58, P=0.0026). The patients' age had no correlation with renal function recovery (r=-0.05, P=0.80). Recovery of renal function in hydronephrosis with extrarenal pelvis was greater than that in hydronephrosis with intrarenal pelvis (P=0.016). Conclusions Postoperative renal function in children with moderate or severe hydronephrosis can recover to normal. Recovery of renal function was more obvious in hydronephrosis with thinner renal parenchyma, longer follow-up period and extrarenal pelvis.