Vesicoureteral reflux in infants: What do we know about the gender prevalence by age?

OBJECTIVE: Vesicoureteral reflux (VUR) affects up to 1% of Caucasian children. Primary VUR is characterized by failure of the ureterovesicular junction to prevent urine from traveling in a retrograde fashion from the bladder to the ureters and the kidneys. Several reports in the literature describe the prevalence of this condition in pediatric patients; overall, VUR affects more males during infancy and with higher grades. However, a thorough consideration of these articles reveals important contradictions regarding the prevalence by gender and age. We analyzed those contradictions and suggested a possible explanation based on our single center experience with this patient group. In particular, for the age interval 0-2 years: we have found that (1) VUR mostly affects boys; (2) the male/female ratio steadily declines over time; (3) the unequal prevalence between males and females essentially disappears when children reach the age of two years. CONCLUSIONS: The natural history of VUR in infant boys differs from that of infant girls, and therefore requires a gender-specific approach. Available data support the need to redefine the categorization and clinical guidelines for this disease.