Cystatin C Concentration During the First Three Postnatal Days in Healthy Term Newborns

Area of Science:

• Neonatal Medicine
• Clinical Chemistry
• Biomarker Research

Background:

• Cystatin C (Cys-C) is a protein used as a marker for kidney function.
• Reference values for Cys-C in healthy term newborns are not well-established.
• Understanding Cys-C levels in neonates is crucial for early detection of renal issues.

Purpose of the Study:

• To establish gender-, postnatal age-, and birth weight-specific reference values for Cys-C in healthy term newborns.
• To compare measured Cys-C concentrations with existing reference intervals, such as those from the CALIPER study.
• To investigate factors influencing Cys-C levels in the neonatal period.

Main Methods:

• Serum samples from 90 healthy term newborns were analyzed.
• Cystatin C concentration was measured using particle-enhanced turbidimetric immunoassay (PETIA).
• Measurements were performed within the first three days of life using the Architect plus ci8200 analyzer.

Main Results:

• The median Cys-C concentration was 2.05 mg/L.
• No statistically significant differences in Cys-C levels were found based on gender, birth weight, postnatal age, or Apgar score.
• The 2.5th-97.5th percentile ranges for girls and boys were 0.93-3.15 mg/L and 1.5-3.36 mg/L, respectively.

Conclusions:

• Neonatal Cystatin C concentration is independent of gender, birth weight, postnatal age, and Apgar score.
• The established Cys-C reference range in healthy newborns was slightly wider than that reported by the CALIPER study.
• These findings provide essential reference data for neonatal kidney function assessment.