eGFR values and selected renal urine biomarkers in preterm neonates with uncomplicated clinical course

Abstract

Background. Diagnosing acute kidney injury (AKI) in preterm newborns, who are particularly susceptible to renal damage, is a serious challenge as there is no definite consensus about the diagnostic criteria. Objectives. The objective of this study was to measure the values for selected urinary biomarkers and estimated glomerular filtration rate (eGFR) among a population of preterm infants with uncomplicated clinical course as well as to determine whether these markers depend on birth weight (BW), gestational age (GA), postnatal age (PNA), or gender. Material and methods. The prospective study was carried out in neonatal intensive care unit (NICU). The evaluation included 57 children that were divided into 3 categories according to BW: low birth weight (LBW)-1501-2500 g (22 infants); very low birth weight (VLBW)-1000-1500 g (25 infants); and extremely low birth weight (ELBW)-750-999 g (10 infants). Urine samples were collected daily between the 4 th and 28 th day of life for measurements of creatinine (Cr), neutrophil gelatinase-associated lipocalin (NGAL), osteopontin (OPN), and human kidney injury molecule 1 (hKIM1). Results. The values of the 3 urine tubular biomarkers, serum creatinine and eGFR were taken in substantially healthy preterm infants with normal kidney function at 4 time intervals during the neonatal period. Their correlations were determined and a multivariable regression analysis was carried out with respect to BW, GA, PNA, and gender. Trends of the studied markers in terms of PNA and BW were also assessed with the Jonckheere-Terpstra test. Conclusions. Glomerular and tubular function in preterm neonates during the 1 st month of life is significantly influenced by BW, GA, PNA, and gender.

Renal volume of five-year-old preterm children are not different than full-term controls

“…Moreover, the renal function parameters were also not different, similar to that of Miklaszewska et al. 27 Renal volumes correlate tightly with the body surface area, the relationship between renal volumes and body surface area never changes during childhood. 13 Renal volume z- scores are independent of age in childhood.…”

Does high protein intake cause tubular injury in very preterm neonates?

“…Nonetheless, uNGAL/Cr ratio increases by 4.4% with a 1 day increase in post-natal age (95% CI: -5,6; (-3,2)). 26 We also found that the median protein intake received by participants at post-natal age 0-48 hours (2 (range: 0.72-3.48)) g/kg/day, 72 hours (3.12 (range: 0.87-4)) g/kg/day, and 21 days (3.44 (range: 2 -5.18)) g/kg/day were lower than our NICU guidelines. Even though the protein intake was lower than expected, the weight to age z-score (WAZ) at 21 days post-natal age according to the IPNG curve showed that 32 of 39 VPN had an increase in body weight compared to their birth weight.…”

“…No pediatric nephrologist consultations were received from participants. Sepsis, nephrotoxic medication, and RD were recorded in26…”

Does High Protein Intake Cause Glomerular Injury in Very Preterm Neonates?

“…Nonetheless, uNGAL/Cr ratio increases by 4.4% with a 1 day increase in post-natal age (95% CI: -5,6; (-3,2)). 19 We also found that the median protein intake received by participants at post-natal age 0-48 hours (2 (range: 0.72-3.48)) g/kg/day, 72 hours (3.12 (range: 0.87-4)) g/kg/day, and 21 days (3.44 (range: 2-5.18)) g/kg/day were lower than our NICU guidelines. Even though the protein intake was lower than expected, the weight to age z-score (WAZ) at 21 days post-natal age according to the IPNG curve showed that 32 of 39 very preterm neonates had an increase in body weight compared to their birth weight.…”