ESPN 54th Annual Meeting

ESPN 2022

Follow up of extremely preterm neonates with nephrocalcinosis – a single center experience
Austeja Ivaskeviciene 1 Violeta Sevcenko 1 Rasa Garunkstiene 1 Arunas Liubsys 1 Andrius Cekuolis 1 Rimante Cerkauskiene 1

1- Vilnius University Faculty of Medicine, Vilnius, Lithuania

Preterm neonates are at risk of nephrocalcinosis (NC). The etiology of NC is multifactorial. There is insufficient data whether prematurity increases the risk of NC and renal failure later in life itself, or if there are any other additional risk factors such as high vitamin D concentration. The aim of our study was to investigate whether extreme prematurity, vitamin D concentration, hypercalcemia and hypercalciuria affects kidney function and nephrocalcinosis development.

Material and methods:

A prospective study of extremely preterm infants ≤ 31 weeks of gestational age with NC born in Vilnius University Hospital Santaros Klinikos between 2018-2022 was performed. The following data was collected at birth and with a follow up at 1, 6, 12 and 24 months: weight, height, vitamin D, serum calcium, urine calcium/creatinine ratio and renal ultrasound.



Out of 160 extremely preterm infants 45 (28%) had NC, 66.7% of them were boys. Mean age was 27.4 ± 2.2 weeks. Mean birth weight 1063.1 ± 326.0 g, and height 34.9 ± 4,3 cm. At age of 6 months calcium/creatinine ratio was 1,28 [0.45-1.99] with NC vs. 0.45 [0.22-1.04] without NC. There was no correlation between vitamin D concentration and NC in all age groups. NC persisted in 69.8%, 62.5% and 46.2% after 6, 12, 24 months respectively. After 6 and 12 months NC was more frequent 6.4 [1.53-26.78] (p=0,01) and 5.6 [1.146-27.37] (p=0,015) after more than 66 days of hospitalization. respectively A positive family history of kidney stones was 26.7%.




Longer hospitalization and hypercalciuria, but not vitamin D and serum calcium concentration were risk factors for NC. Long term follow up of extremely premature infants with NC is recommended.