Natural history of vesicoureteral reflux associated with kidney anomalies

Objectives. To evaluate the cystographic follow-up of patients with multicystic dysplastic kidney (MCDK), renal agenesis, and renal ectopia with associated primary vesicoureteral reflux (VUR). Methods. Patients with primary associated VUR (grade 2 or more) and with a minimal follow-up of 24 months were included in this study. Results. Of the children with renal agenesis, 24% had VUR. The median grade of VUR was significantly greater in the boys than in the girls (4 versus 2, respectively; P <0.05). All girls and 34% of the boys experienced spontaneous resolution 1 year after diagnosis; 66% of the boys required operative treatment. Of the patients with MCDK, 16% had VUR. The median grade of VUR in the kidney contralateral to the MCDK was greater in the boys than in the girls (3.5 versus 2, respectively; P = 0.06). All girls and 60% of the boys had spontaneous resolution 1 year after diagnosis; 40% of the boys underwent operative treatment. Of the children with renal ectopia, 30% had VUR. The median grade of VUR for the refluxing unit was significantly greater in the girls than in the boys (3 versus 2, respectively; P <0.05). Spontaneous resolution of VUR was observed in all boys (66% at 1 year) and in 40% of the girls; 60% of the girls required operative treatment. Conclusions. Spontaneous resolution of VUR can be anticipated in girls with MCDK or renal agenesis and in boys with renal ectopia. These data can be used in planning the proper follow-up schedule for babies with a kidney anomaly detected by ultrasonography.