Role of renal dynamic imaging in evaluation of impairment of renal function in pediatric congenital hydronephrosis

Objective: Congenital hydronephrosis is a common prenatally diagnosed anomaly associated with an incidence of approximately 0.5-1% in newborns. The purpose of this study was to clarify the value of 99 m diethylenetriamine pentaacetic acid (99mTc-DTPA) in the assessment of renal function impairment of pediatric hydronephrosis. Methods: A total of 48 children with unilateral ureteropelvic junction obstruction were enrolled and subjected to 99mTc-DTPA diuretic renography examination. The glomerular filtration rate (GFR), renal blood perfusion rate (BPR) and peak uptake rate (PUR) were quantitatively analyzed with the aid of renal dynamic imaging system. The blood urea nitrogen (BUN), serum creatinine (Scr) and hemoglobin (Hb) in each patient were also measured. Correlation analysis was used to evaluate the relationship of GFR, BPR, PUR with BUN, Scr and Hb. Results: Diuretic renography results showed that GFR, BPR and PUR in children with hydronephrosis were gradually reduced with the aggravation of the hydronephrosis. The BUN and Scr were negatively, but the Hb was positively relevant with the GFR, BPR and PUR in children with severe hydronephrosis. The GFR, BPR and PUR in children with mild or moderate hydronephrosis were negatively related with Scr. Conclusion: Diuretic renography with 99mTc-DTPA may effectively reflect the degree of hydronephrosis and impairment of renal function, and may be employed as an ancillary diagnostic tool for pediatric congenital hydronephrosis. It is also used for evaluation of improvement in renal function after operation.