Correlation of High-Grade Vesicoureteral Reflux and Renal Ultrasound Findings

Background : Urinary tract infection(s) are common in children and evaluation of risk factors, primarily vesicoureteral reflux, is necessary to determine potential for reflux nephropathy. Voiding cystourethrogram remains the standard for evaluation of VUR, but not without invasiveness, cost, and radiation exposure. Screening occurs with renal ultrasound and progresses to VCUG if abnormalities are noted. Our study was designed to evaluate the utility of RUS in identifying VUR. Methods : Charts of patients diagnosed with UTI were reviewed for RUS and VCUG. Abnormal RUS and VCUG were graded according to accepted standards. Each kidney, defined as separate renal unit. Sensitivity, specificity, positive and negative predictive values were calculated for all grades of VUR. Results : Of the 793 renal units (age range birth to 18 years) analyzed, 217 (27.4%) demonstrated an abnormal RUS and 132 (16.6%) revealed reflux on VCUG. All grades of VUR were present in 46 units with abnormal RUS, indicating a 34.8% sensitivity, 74.1% specificity, 21.2% PPV, and 85.1% NPV. High-grade reflux (IV-V) was present in 19 units with a 67.9% sensitivity, 74% specificity, 41.3% PPV, and 89.5% NPV. Conclusion : RUS only provides some certainty when negative, but its ability to predict VUR remains modest even when considering high-grade reflux.