A 5-year audit of 778 neonatal renal scans (Part 1): perplexing pyelectasis and suggested protocol for investigation.

In this 5-year review of 778 neonatal renal scans seen in an Obstetric Hospital, most infants were referred because of antenatal ultrasound findings, 92% with fetal pyelectasis. The results were classified according to the ultrasound findings. The majority of neonates (76%) had a normal postnatal scan. A number had vesicoureteric reflux (VUR) found on a micturating cystourethrogram. Persistant mild to moderate pyelectasis or hydronephrosis (15%) proved to be a normal variant in many infants, but had a similar appearance to those with an early obstructive cause (1%). Pyelectasis has proved to be a poor predictor of VUR. A protocol outlining paediatric management for neonates with persisting pyelectasis is included. There were 59 infants (8%) with a miscellaneous group of renal anomalies, many with a characteristic antenatal ultrasound appearance suggesting the diagnosis. These infants have been separately reported and illustrated (Part 2). Overall, 13% of infants were found to have significant findings of obstruction, VUR or miscellaneous anomalies affecting management.