Kidney Week

Abstract: PO2015

Postnatal Maturation of Glomerular Filtration Rate in Term Born Neonates: An Individual Patient Data Meta-Analysis

Session Information

• Pediatric Nephrology: Genetics, Kidney Stones, Quality Improvement, and Case Reports
  November 04, 2021 | Location: On-Demand, Virtual Only
  Abstract Time: 10:00 AM - 12:00 PM

Category: Pediatric Nephrology

• 1700 Pediatric Nephrology

Authors

• Smeets, Nori, Radboud University Medical Center, Nijmegen, Netherlands

Nori Smeets

• IntHout, Joanna, Radboud University Medical Center, Nijmegen, Netherlands

Joanna IntHout,

• van der Burgh, Maurice Jerôme Philippe, Radboud University Medical Center, Nijmegen, Netherlands

Maurice Jerôme Philippe van der Burgh,

• Schwartz, George J., University of Rochester, Rochester, New York, United States

George J. Schwartz,

• Schreuder, Michiel F., Radboud University Medical Center, Nijmegen, Netherlands

Michiel F. Schreuder,

• de Wildt, Saskia, Radboud University Medical Center, Nijmegen, Netherlands

Saskia de Wildt,

Background

The evidence from individual studies to support the maturational pattern of measured glomerular filtration rate (GFR) in healthy term born neonates is inconclusive. This hampers the delineation between normal and abnormal kidney development as well as the diagnosis of acute kidney injury (AKI). Thus, we aimed to describe GFR maturation in the first month of life using an individual patient data meta-analysis (IPDMA) of measured GFR data.

Methods

The Pubmed and ClinicalTrials.gov databases were searched to identify studies reporting mGFR as measured by exogenous markers or creatinine clearance (CrCL) in healthy term born neonates. Articles were subsequently reviewed by two individual researchers. The relationship between postnatal age and individual clearance values was investigated using restricted cubic splines with generalized additive linear mixed models on individual data, taking into account clustering by study. Data from aggregated studies were used for sensitivity analyses.

Results

1521 articles were screened and 50 relevant studies reported mGFR in healthy term born neonates. In total, 1055 measured GFR values from 958 neonates were included. Individual patient data (IPD) were available for 371 neonates and 587 neonates were represented by 46 aggregated datapoints as means/medians per cohort. Mean GFR increases rapidly in the first five days after birth from 16.8 (95% CI 11.2-22.5) ml/min/1.73m² at the first day to 39.8 at day 5 (95% CI 35.8-43.7), followed by a more gradual increase to 59.4 (95% CI 45.9-72.9) ml/min/1.73m² at end of the fourth week.

Conclusion

These normative values show a clear developmental pattern of GFR maturation in the first weeks of life and indicate a biphasic increase with the largest increase until day 5. Our IPDMA data can therefore serve as a useful baseline for neonatal GFR.

The development of GFR in the first month of life in term born neonates. Black line represents p50, darker blue area indicates p25-p75, lighter blue area indicates p10-p90.