RESUMO
PURPOSE: To assess the outcome of successful pyeloplasty in infants with Ureteropelvic Junction Obstruction (UPJO) and a differential renal function of (DRF) < 35% whether they can attain normal postoperative renal function or not. METHODS: All children who were diagnosed with antenatal hydronephrosis due to UPJO were presented to our institutions and were prospectively followed up. Pyeloplasty was performed based on predefined indications such as: initial DRF ≤40%, progression of hydronephrosis, and febrile urinary tract infection (UTI). A total of 173 children, who had successful surgical intervention due to impaired DFR, were divided according to their pre-intervention DRF value as follows: DRF <35% (group I) and DRF 35-40% (group II). The renal morphology and function changes were recorded and used for comparison between both groups. RESULTS: Group I was comprised of 79 patients, and group II included 94 patients. Pyeloplasty achieved significant improvement in the anatomical and functional indices in both groups (p-value <0.001). The degree of improvement in Anteroposterior diameter (APD) and cortical thickness was comparable in both groups (P-value, 0.64 and 0.44 respectively). While the improvement in the DRF was significantly higher in group I (16.06 ± 6.6) than in group II (6.25 ± 2.66) (P-value <0.001). Despite that, a significantly higher percentage of infants in group II (61.7%) achieved normal final DRF compared with only (10.1%) in group I (Figure). CONCLUSION: Even in severely impaired renal function (<35%), successful pyeloplasty can recover a significant part of lost renal function. However, most of these patients do not achieve normal postoperative renal function.
