Functional and Morphological Outcomes of Pyeloplasty at Different Ages in Prenatally Diagnosed Society of Fetal Urology Grades 3-4 Ureteropelvic Junction Obstruction: Is It Safe to Wait?

OBJECTIVE: To evaluate changes in functional and morphological outcomes in children with prenatally diagnosed Society of Fetal Urology (SFU) grades 3-4 ureteropelvic junction obstruction (UPJO) who underwent pyeloplasty at different ages. We also examined the effect of surgical wait time on recovery of renal function.

MATERIALS AND METHODS: All patients (aged 0-12 months) with prenatally diagnosed SFU grades 3-4 UPJO who underwent pyeloplasty in a single center between January 2013 and December 2015 were reviewed. One hundred thirty-three children were enrolled in this study. The children were divided into 2 groups according to their age at the time of surgery (group I: 0-3 months, group II: 3-12 months). We evaluated changes in parenchymal thickness, anteroposterior diameter (APD), and differential renal function (DRF) using ultrasound and diuretic renography. Functional and morphological outcomes were compared using Student t test.

RESULTS: A total of 133 patients were included in the study. We found a significant difference in the change of DRF (difference between before and after pyeloplasty) between the 2 groups (P < .05). There were no significant differences in changes in parenchymal thickness and APD. Patients who waited 1-2 months had a significantly lower functional improvement compared with those who waited less than 1 month.

CONCLUSION: Early surgery leads to a significant improvement in DRF. Wait times greater than 1 month can decrease functional improvement. For patients with prenatally diagnosed SFU grades 3-4 UPJO, early pyeloplasty is recommended in those with increasing renal pelvic APD and an obstructed renogram with differential renal function <40%.