Is a complete urological evaluation necessary in all newborns with asymptomatic renal ectopia?

AIM: To evaluate if a complete urological screening is justified by potential urological anomalies in newborns or infants with asymptomatic renal ectopia (RE). METHODS: The database records of 60 consecutive neonatal cases of RE diagnosed at the authors' hospital from 1990 to 2004 were retrospectively reviewed. RESULTS: At diagnosis, mean patient age was 1.6 months. In 58 of 60 patients, the suspected diagnosis of RE was made during prenatal or postnatal screening ultrasonography, including two newborns with anorectal malformation. There were 24 patients with crossed RE (C-RE) and 36 patients with simple RE (S-RE). A solitary RE was present in two patients. The most frequent associated urological abnormality was vesico-ureteral reflux (37.5% of C-RE and 16.6% of S-RE). Hydronephrosis was detected in seven RE and five contralateral kidneys. An obstructive megaureter was present in one patient with C-RE. In 40% of S-RE and 92.9% of C-RE, the (99m)Tc DMSA documented reduction of function of RE. The longitudinal diameter of the ectopic kidney was significantly smaller than the contralateral one. Other non-renal diseases were present in 15% of patients, of which the most frequent was cryptorchidism (6.6%). CONCLUSIONS: A complete urological evaluation is necessary in newborns with C-RE for the high incidence of associated urological anomalies, of which VUR is the most frequent. A complete urological evaluation is also reasonable in patients with S-RE who have a pelvic dilatation. No diagnosis or treatment of the associated urological diseases, in consideration of congenital decreased function of the ectopic kidney, might predispose these children to improvement of renal function impairment.