Background and objectives: Nephrocalcinosis (NC) is a common condition characterized by the deposition of calcium salts in the kidneys of very preterm infants due to tubular immaturity, intensive treatment and nutritional supplements. However, optimal vitamin D supplementation remains unclear. In most patients, NC spontaneously resolves within the first year of life, but long-term kidney function data are lacking. The aim was to study nephrocalcinosis in very preterm infants, assess risk factors and evaluate vitamin D’s impact during the first month with a 2-year follow-up. Material and Methods: This was a prospective observational study conducted over a 3-year period in infants with a gestational age of less than 32 weeks. The patients’ data were compared between the NC and control groups based on kidney ultrasound results at discharge. In the first month, the mean vitamin D intake from all sources as well as biochemical markers of calcium metabolism were collected. Patients diagnosed with NC were referred to a pediatric nephrologist after discharge. Results: NC was found in 35% of a cohort of 160 infants, more common in those with a gestational age <28 weeks. Risk factors were associated with higher morbidity and necessary treatment. At 28 days, serum 25-hydroxy vitamin D levels differed between NC and control groups (p < 0.05). The NC group with GA ≥ 28 weeks had higher vitamin D intake (p < 0.05), hypercalciuria and calcium/creatinine ratio (p < 0.01) and lower parathyroid hormone levels (p < 0.05). Follow-up showed resolution in 70% at 12 months and 90% at 24 months. Conclusions: The prevalence of NC in very preterm infants is significant, associated with lower maturity and higher morbidity. Careful vitamin D supplementation and biochemical monitoring of Ca metabolism from the first month of life should support bone health and limit the risk of nephrocalcinosis. Due to the high incidence of NC in very preterm infants, long-term follow-up is essential.

Background: Changes in lung ventilation are well documented in term neonates while in late preterm neonates these patterns are poorly understood despite their increased risk of respiratory morbidity. Objectives: The study aimed to compare and clarify the differences in regional lung ventilation of late preterm and term neonates during the early adaptation period using electrical impedance tomography (EIT). Material and methods: The case-control study was conducted in the years 2020–2022. It included 51 late preterm neonates (LPN, Study group) and 45 term neonates (TN, Control) born by normal vaginal delivery (NVD). EIT examinations were performed with a Swisstom BB2 (Switzerland) equipment. The data recordings were performed no later than 30 (I Record), 60 (II), and 90 (III) minutes after the birth. Results: Statistically significant differences between LPN and TN were observed in the non-dependent lung areas at I record, with more silent spaces observed in the LPN (p < 0.001). Differences in the dependent lung regions were observed across all recordings, with LPN demonstrating more silent spaces (p < 0.001). LPN demonstrated greater stretch-related changes in the 10% and 20% stretch categories across all recordings, while TN showed greater changes in the 50%, 70%, and 90% categories. Tidal volumes in the right lung of TN are distributed more towards the ventral and central ventral regions. In contrast, tidal volumes of LPN are distributed to the central dorsal and dorsal regions of the right lung. Conclusions: LPN during the first 90 min after the birth show reduced lung ventilation assessed by EIT, suggesting a possible impairment of early postnatal adaptation.

Background: Respiratory distress syndrome (RDS) is a frequent cause of invasive respiratory support. Our study aims to assess end-expiratory lung impedance (EELZ) and DeltaZ changes post-suction using electrical impedance tomography. Methods: Very low birth weight infants with gestational ages less than 32 weeks under conventional mechanical ventilation with an open endotracheal suction system were included in this study. Data was evaluated at four time periods: immediately after the completion of suctioning and at 1, 5 and 10 min marks post-suction. Results: Sixteen patients participated in this study, during which a total of 31 suctioning events were recorded. There were no significant hypoxemic events during the analyzed timeframe. Over a 10 min period following suction, there was a consistent change in EELZ and DeltaZ, with EELZ decreasing and DeltaZ increasing accordingly (p < 0.001). Conclusions: Our study demonstrated that EELZ and DeltaZ changes persist even 10 min after suctioning using an open endotracheal suction system.