Does preoperative screening VCUG affect the outcomes and complications of pyeloplasty in patients with ureteropelvic junction obstruction?

Abstract

The role of voiding cystourethrogram (VCUG) in evaluating vesicoureteral reflux (VUR) in patients with known ureteropelvic junction obstruction (UPJO) remains unclear. While VCUG is frequently performed, the incidence of concomitant VUR and UPJO is low, and VUR is often low-grade with high rates of spontaneous regression. To analyze the clinical relevance of VCUG in patients with UPJO by determining its incidence and studying the difference in clinical outcomes between patients with known, unknown, and negative VUR. Retrospective review of patients with UPJO who underwent pyeloplasty from 2012 to 2020 with <18 years-old, unilateral UPJO, postoperative follow-up of ≥2 months and had at least 1 renal ultrasound (US) after pyeloplasty. Results were compared among 3 groups: patients who underwent VCUG before pyeloplasty and were found to have VUR (group 1), patients who underwent VCUG before pyeloplasty without VUR (group 2), and patients who did not have a VCUG before pyeloplasty (group 3). A total of 275 patients met the inclusion criteria, of which 21 patients were classified in group 1, 166 patients in group 2, and 88 patients in group 3 (Table). The age at preoperative VCUG was 14.7±32.9 months in group 1 and 15.17±35.8 months in group 2 (p=0.960). Overall, the incidence of concomitant UPJO and VUR was 11.2%. In group 1 the initial VUR grade was 5 in 2 patients, 4 in 3, 3 in 5, 2 in 7, and 1 in 4 patients. Of these, only 1 patient required ureteral reimplantation after pyeloplasty. Post-pyeloplasty, no significant differences were observed in complications (p=0.7436), length of follow up (p=0.3212), SFU grade 4 hydronephrosis (p=0.2247), postoperative UTIs (p=0.1047) and pyeloplasty success rate (p=0.4206) among the 3 groups. Despite the use of antibiotic prophylaxis being significantly different amongst the three groups (p<0.001), it was not associated with a lower incidence of postoperative UTIs (group 1 p=0.068, group 2 p=0.486, group 3 p=1). In patients with reflux, an increase in age was associated with a decrease in the rates of complications (p=0.019). We found no significant difference in the outcomes in patients who had a preoperative VCUG as compared to those who did not. The preoperative diagnosis of VUR by VCUG changed the management in less than 1% of the study population and thus its role in patients with UPJO should be reevaluated.