Incidence and severity of vesicoureteral reflux in children related to age, gender, race and diagnosis.

Purpose: We determine if the incidence and grade of vesicoureteral reflux (VUR) differs in children based on age, race and gender, and if the incidence and severity of VUR are related to race in girls younger than 7 years presenting for evaluation after urinary tract infection (UTI).
Materials and Methods: The records of all children who underwent a voiding cystourethrogram or radionuclide cystogram between 1993 and 2001 were retrospectively reviewed. Age, gender, race, clinical indication and highest grade of VUR were recorded for the first voiding cystourethrogram or radionuclide cystogram. Frequency tables and logistic regression were conducted to correlate demographics to incidence and severity of VUR.
Results: A total of 15,504 patients were included in the analysis. Overall, black children were a third as likely as white children (p <0.0001) and females were twice as likely as males (p <0.0001) to have VUR. Compared to children 0 to 2 years old, the occurrence of reflux was 0.5 times as likely in those 3 to 6 years old (p <0.0001), 0.3 times as likely in those 7 to 11 years old (p <0.0001) and 0.15 times as likely in those 12 to 21 years old (p <0.0001). When analyzing children with UTI, results were similar. Of the patients with VUR 65% were younger than 7 years. The incidence of VUR in black girls younger than 7 years with a diagnosis of UTI was less than 10% compared to white girls, and no black girl had high grade reflux. In young children referred for UTI the incidence and severity of VUR in black patients were significantly lower than those of white girls.
Conclusions: This study validates previous observations regarding the low incidence of VUR in black children.