Evaluation for Vesicoureteric Reflux Following Febrile Urinary Tract Infections

Excerpt

Urinary tract infections (UTI), among the most common infections in childhood, are important to recognize and treat because pyelonephritis carries a risk of permanent renal injury. Parenchymal scars are observed in 10–15% of patients with first episode of UTI [1]. Since vesicoureteral reflux (VUR) and bladder bowel dysfunction (BBD) are important risk factors for recurrence of UTI, evaluation following an episode of UTI focuses on detecting such ‘at-risk’ patients. Based on the performance and timing of ultrasonography, voiding cystourethrogram (VCUG) and dimercaptosuccinic acid (DMSA) scan, two approaches to evaluation are conventionally recognized [2]. While ultrasonography rules out significant structural malformations and gross pelvicalyceal or ureteric dilatation, it has low sensitivity for VUR. Hence, the ‘bottom-up’ approach, which intends to detect all VUR, relies on performing VCUG, followed by DMSA in those with VUR. In contrast, the ‘top-down’ approach recommends ultrasonography and DMSA during acute infection, limiting performance of VCUG to patients in whom DMSA suggests pyelonephritis. While the former approach is more often feasible, cost-effective and sensitive, it involves the discomfort associated with urinary catheterization. On the other hand, the ‘top-down’ approach is limited by cost and lack of availability of DMSA, significant inter-observer variability in its reporting, higher exposure to radiation than with VCUG, and low sensitivity in detection of VUR [2]. Diagnosis of VUR by direct radionuclide cystography, magnetic resonance urography or contrast-enhanced voiding cysto-ultrasonography, while promising, is yet to find application in current algorithms [2]. …