INCIDENCE AND SEVERITY OF VESICOURETERAL REFLUX IN SIBLINGS OF CHILDREN WITH KNOWN REFLUX

Background: The incidence of primary vesicoureteral reflux (VUR) is less than 1% in the general normal population, but it is high in siblings of children with VUR, with a reported incidence of 4.7-51%. VUR represents one of the most significant risk factors for acute pyelonephritis in children and caries long-term renal parenchymal damage. The purpose of this study was to detect the age-related incidence, and severity of reflux, in siblings of children with reflux. Methods: Out of 80 index patients with VUR, 95 siblings were evaluated with direct voiding cystography from 1994 to 2004. All siblings underwent renal ultrasonography (US) for size, shape, parenchymal echogenicity, corticomedullary differentiation, irregularity of the kidney outlining, and parenchymal reduction. Findings: Out of 95 siblings, 34 had VUR, representing an incidence of 35.8%. The mean age at study entry of the 37 boys and 58 girls was 65 months (range 3 months to 13 years). Reflux was unilateral in 22 siblings and bilateral in 12. Of the 34 refluxing siblings (46 refluxing ureters), 12 (35.3%) had history of symptomatic urinary tract infection (UTI). Of the 46 refluxing units 22 were mild, 13 moderate, and 11 were severe. Conclusion: Reflux is low in the majority of siblings. This study confirms a significant overall incidence of VUR (35.8%) in the siblings of patients with known reflux. Additionally, our review suggests that all siblings over 6 years should undergo a screening for VUR because of the high likelihood of identifying reflux in this population, even in the absence of urinary tract infection.