[Prenatal hydronephrosis: incidence, management and final diagnoses in 2003]

Prenatal diagnosis of renal pyelectasis usually involves postnatal studies to determine whether treatment is necessary or not.

To determine the incidence of fetal pyelectasis in our environment, to review our postnatal management protocol, and to review definitive diagnoses.

We performed a retrospective review of newborns with a prenatal diagnosis of pyelectasis. The variables recorded included prenatal ultrasound examinations, gestational age, sex, anthropometric data, postnatal study (ultrasound, cystography, isotopic renogram) and indication for antibiotic prophylaxis.

There were 21 newborns (nine boys and 12 girls). Pyelectasia were located in the right kidney in 10 patients, on the left in seven and were bilateral in four. Antibiotic prophylaxis was administered at birth in seven neonates. Postnatal ultrasound was performed at 17.19 +/- 12.7 days of life and revealed no abnormalities in seven patients, hydronephrosis grade I-II in nine, hydronephrosis grade III in three and suspected double excretion system in two. Cystourethrography and isotopic renogram were performed in six neonates. The definitive diagnoses in the 21 patients were: no abnormalities in 10, non-complicated renal dilatation in seven, double excretion system in two, vesicoureteral reflux grade IV in one and pyeloureteral stenosis in one. None of these newborns had urinary tract infection.

The incidence of prenatal pyelectasis in our hospital is 2 %. Most pyelectasia resolve spontaneously in the first year of life and invasive investigations are not required. Adequate monitoring of these children can avoid urinary tract infections and their sequelae.