What to Expect on the Long-term Follow-up of Pediatric Pyeloplasty: Critical Time Intervals and Risk Factors.

ABSTRACT

BACKGROUND: Standard protocol for post-pyeloplasty monitoring in children and natural course of hydronephrosis resolution have not been well defined. We aimed to analyze critical time intervals and risk factors in the long-term clinical outcomes of children who were operated for ureteropelvic junction obstruction. METHODS: Files of patients who underwent open dismembered pyeloplasty between January 2000 and December 2012 and had a ≥10 years follow-up were retrospectively reviewed. Changes in SFU hydronephrosis grade, pelvis anteroposterior diameter (APD), renal parenchymal thickness, split renal functions (SRF) on MAG-3 scan as well as development of hypertension and proteinuria were noted. Complete resolution was defined as SFU grade 0-1 or APD≤10 mm or ≥50 % APD decrease. RESULTS: Overall, 223 patients (161 boys, 72.1 %) with a median age of 9 (range 1-185) months underwent unilateral pyeloplasty, whereas 14 patients (13 boys, 92.8 %) with a median age of 4 (range 2-39) months underwent bilateral pyeloplasty. Median follow-up was 13 (range 10-22) years. Complete resolution was observed in 190 patients (85.2 %). None of the cases required re-do pyeloplasty. Regarding unilateral cases, postoperative changes in hydronephrosis reached a plateau at the 60th month. Also, there was no significant difference regarding SRF between the 12th month and the 60th month (p > 0.05). Hypertension developed after a median period of 12 years in 13 (5.4 %) of the patients, while proteinuria developed in four (1.6 %) patients. Bilateral disease (HR 2.518, p = 0.034) was found to be a significant determinant for development of hypertension and/or proteinuria. CONCLUSIONS: Our results indicated that ultrasonographic findings stabilized after the 60th month postoperatively, and SRF remained stable between the postoperative 12th and the 60th months. The risk of developing hypertension and/or proteinuria was 2.5 times greater in bilateral cases. LEVEL OF EVIDENCE Level II.