Assessing the Predictive Ability of the Pyeloplasty Prediction Score on Surgical Outcomes: A New Use of a Tool in Pediatric Urology

Abstract: Background: Pediatric urology requires precise surgical techniques and effective communication with parents. Establishing trust through knowledge sharing is essential for guiding treatment pathways. Parents, particularly those with antenatal diagnoses, seek reassurance through counseling. Antenatal hydronephrosis, affecting approximately 1 in 1000-1500 live births, often involves conditions like Pelviureteric junction obstruction (PUJO). Various scoring systems, including the ultrasound-based Pyeloplasty Prediction Score, assist in predicting surgical outcomes. Leveraging such scores as counseling tools enhances parental understanding and facilitates informed decision-making in pediatric urology. Objective: To evaluate the predictive ability of Pyeloplasty Prediction Score on surgical outcomes of Pyeloplasty and to assess the use of this score as a counselling tool. Materials and Methods: This prospective study, conducted at the Department of Urology, Tabba Kidney Institute, enrolled 50 patients under 15 years with antenatal hydronephrosis or incidental diagnosis of HDN. Patients over 15 years of age and those with bilateral hydronephrosis were excluded. The Pyeloplasty Prediction Score, comprising SFU grade, Anteroposterior Pelvic Diameter (APPD), and percentage renal length difference, was used for risk stratification. Scores were categorized as low (≤4), intermediate (5-7), or high (≥8) risk. Post-pyeloplasty, patients were monitored for hydronephrosis resolution and cortical thickness gain via ultrasound. Resolution was defined as APPD less than 10mm or more than 50% decrease from preoperative value. Result: Out of the enrolled 50 patients, with a mean age of 6 years (range: 2 months to 11 years), 28 (56%) were female and 22 (44%) were male. 56% presented with antenatal hydronephrosis, while 44% had incidental PUJO-like HDN. 20 patients (40%) were categorized as high risk, and 30 patients (60%) as intermediate, with none in the low-risk group. Laparoscopic Retroperitoneal Pyeloplasty was performed in 19 patients (38%) above 2 years, and open Pyeloplasty with DJ stenting in 31 patients (62%) below 2 years. Postoperatively, 24 patients (80%) in the intermediate-risk group showed cortical thickness gain, compared to 9 patients (45%) in the high-risk group (p=0.05). Resolution of hydronephrosis was observed in 13 patients (65%) in the high-risk group and 12 patients (40%) in the intermediate-risk group, possibly due to pelvis excision in severely hydronephrotic cases (p=0.78). Conclusion: The Pyeloplasty Prediction Score serves as an effective counseling tool for predicting the outcome of Pyeloplasty in terms of cortical gain, eliminating the need for radioisotope exposure post operatively. However, its effectiveness in predicting hydronephrosis resolution is limited.