Delayed Upper Tract Drainage on Voiding Cystourethrogram May Not Be Associated With Increased Risk of Urinary Tract Infection in Children With Vesicoureteral Reflux

Summary Introduction Urinary stasis in the setting of obstruction provides an opportunistic environment for bacterial multiplication and is a well-established risk factor for UTI. Vesicoureteral reflux (VUR) with delayed upper tract drainage (UTD) on VCUG has been reported to correlate with increased UTI risk. We sought to determine whether delayed UTD can be reliably classified, and whether it correlates with UTI incidence, VCUG, or endoscopic findings. Methods Children undergoing endoscopic surgery for primary VUR (2009–2012) were identified. VUR grade, timing, and laterality were abstracted. Demographics, hydrodistention (HD) grade, reported febrile and culture-proven UTI were assessed. UTD on VCUG was graded on post-void images as 1 = partial/complete UTD or 2 = no/increased UTD. Inter-observer agreement was calculated. Patients were excluded for incomplete imaging or inability to void during VCUG. Results The cohort included 128 patients (10M, 118F), mean age 4.1±2.1 years. Mean age at diagnosis was 2.8±2.8 years. Mean maximum VUR grade was 3±0.9: 1 (7.8%), 2 (20.3%), 3 (43%), 4 (25.8%), 5 (3.1). UTD occurred in 45 (35%), and no drainage in 83 (65%) patients. Agreement coefficient between graders was 0.596 ( p