Antenatal renal pelvis dilatation: 2-year follow-up with DMSA scintigraphy.

The aim of this study was to determine whether a postnatal ultrasound (US) can detect infants with antenatal renal pelvis dilatation (ARPD) who run a minimal risk of renal damage 2 years after birth. The study cohort consisted of 14,000 pregnant women who consecutively underwent routine US examinations during the second trimester. Subsequent examinations were performed on the basis of obstetrical indications. In total, 106 foetuses were diagnosed with ARPD > or =5 mm. Two postnatal US were performed on the newborns: on postpartum days 5-7 and during the third week of life. The findings were considered to be normal when the renal pelvis diameter (RPD) was < or = 7 mm and when there was no calyceal or ureteric dilatation or signs of renal dysplasia or other anomalies. Voiding cystourethrography (VCUG) was done at 6-8 weeks after birth. When the children reached 2 years of age, renal status was evaluated with DMSA scintigraphy or, if not possible, US. In 53 of the 103 children available for evaluation, the postnatal US findings were normal; 49 of the 53 children were also given a DMSA, and the results were normal in all cases. An US scan (all normal) only was performed in three children because the families refused a DMSA. One family refused any form of examination at the 2-year follow-up. Based on our results, we conclude that postnatal US can detect infants who do not require follow-up assessments of renal development.