Coagulation standards in healthy newborns and infants

Area of Science:

• Pediatric Hematology
• Clinical Coagulation Science
• Neonatal Medicine

Background:

• Established coagulation factor ranges for newborns are over 30 years old, predating modern diagnostic technologies.
• Previous studies updating neonatal coagulation standards used small sample sizes, limiting their generalizability.
• Advances in reagents, automated systems, and techniques necessitate updated reference values for accurate clinical interpretation.

Purpose of the Study:

• To establish current, reliable normal coagulation reference ranges specifically for healthy newborns.
• To provide updated standards for key coagulation parameters, including PT and aPTT, using contemporary methodologies.
• To address the limitations of outdated reference values in neonatal diagnostic practices.

Main Methods:

• Included 112 consecutive healthy newborns with pyloric stenosis over a 5-year period.
• Calculated reference ranges using mean ± 2 standard deviations, with normality assessed via graphical methods and Shapiro-Wilk tests.
• Analyzed correlations between coagulation parameters (aPTT, PT) and clinical factors (age, weight) using Spearman's rank correlation.

Main Results:

• Established reference ranges: aPTT 28.6-46.2 s, aPTT ratio 0.91-1.49, PT 71.3-110.6 s.
• Found no significant correlation between aPTT or PT and infant age or weight.
• Provided median values for fibrinogen, Factor II, V, VIII, IX, and XI in the studied newborn cohort.

Conclusions:

• This study provides the largest recent dataset for neonatal PT and aPTT using updated reagents.
• The established reference ranges offer essential standards for coagulation testing in healthy newborns.
• Findings support improved accuracy in diagnosing and managing coagulation disorders in neonates.