Aim: Assessing the postnatal outcome of reduced renal mass due to unilateral renal agenesis(URA), multicystic dysplastic kidney(MCDK) or unilateral ectopic kidney(UEK) as suspected on fetal ultrasound(FUS).
Background: Reduced renal mass has a life-long impact on renal and cardiovascular health. When this situation is suspected, contralateral kidney hypertrophy is considered a good prognostic sign. We evaluated the postnatal outcome of newborns suspected on FUS with URA, MCDK or UEK at the Lis Hospital Fetal Ultrasound Unit during 2008-2014.
Methods: Serial solitary/main kidney fetal length measured on FUS, associated abnormalities and familial health were recorded from prenatal nephrology consultation. Postnatal data for kidney length, function (eGFR) and blood-pressure were retrieved for those with continued follow-up in the Dana-Dweq Pediatric Nephrology Unit.
Main results: 36 newborns with: URA-14, MCDK-9 and UEK-13 suspected on FUS and confirmed after birth were followed for 20mo(median). Familial CAKUT(Congenital Anomalies of Kidneys and Urinary Tract) was reported in 9(25%). Renal and extrarenal anomalies were diagnosed in 12(33%) and 8(22%), respectively. Contralateral kidney compensatory hypertrophy was found on prenatal vs postnatal ultrasound in 50% vs 64% of URA, 22% vs 100% of MCDK and 23% vs 23% of UEK, respectively. Prenatal kidney growth trend lines did not predict postnatal growth/hypertrophy. Renal function =eGFR was (median)147ml/min at median age 22mo. . Hypertensive-range blood pressure values were found in 78%, 66% and 30% of MCDK, UEK and URA, respectively.
Conclusion:
Close monitoring of blood pressure and renal function should start early after birth in newborns with reduced renal mass.
