Applying the pyeloplasty predictive score in patients with ureteropelvic junction obstruction

Abstract

Background: Ureteropelvic junction obstruction (UPJO) is an anatomical lesion in the renal collecting system and is one of the most common congenital causes of hydronephrosis, occurring in 1-5 % of pregnancies. Surgical predictive scores have been extensively studied as a promising way to assist and optimize management in cases of UPJO.

Objective: Apply the pyeloplasty predictive score and evaluate its effectiveness in patients with UPJO treated at a tertiary care hospital.

Study design: The Pyeloplasty Prediction Score (PPS) was retrospectively applied to patients diagnosed with UPJO and treated at a tertiary care hospital. The PPS is based on the Society for Fetal Urology grading system, the anteroposterior diameter of the pelvis, and the absolute percentage of the difference in renal length. The PPS ranges from 0 to 12 and is calculated by adding each of the scored variables, classifying surgical risk as low, intermediate, and high.

Results: Out of the 48 kidney units studied, 18 did not undergo surgical treatment, and 30 underwent pyeloplasty. The number of units with low, intermediate, and high non-surgical PPS was 8, 8, and 2, respectively, and surgical PPS was 1, 8, and 21. The sensitivity of the PPS was 96.67 %, and the specificity was 44.44 %. The positive predictive value was 74.36 %, and the negative predictive value was 88.89 %.

Discussion: The majority of surgical kidney units had a high score. The only patient operated on with low risk had associated vesicoureteral reflux in the same unit. Half of the non-surgical patients had a low score. The two high-risk non-surgical cases had megacalicosis as the final diagnosis.

Conclusion: PPS may aid the clinical practice of UPJO due to its high sensitivity in high and low scores, necessitating an individualized clinical and radiological assessment in intermediate-risk cases.

Keywords: Hydronephrosis; Surgery; Ultrasound; Ureteropelvic junction obstruction.