Vitamin K Biochemistry and Pharmacokinetics: The Basis of Late Vitamin K Deficiency Intracranial Bleeding in Early...

Area of Science:

• Biochemistry
• Pharmacokinetics
• Neonatal Medicine

Background:

• Neonates are highly susceptible to vitamin K deficiency due to physiological factors and limited intake.
• Vitamin K is vital for coagulation and other essential physiological functions.
• Late vitamin K deficiency bleeding (VKDB) remains a concern despite birth prophylaxis.

Purpose of the Study:

• To review vitamin K's biochemistry and pharmacokinetics in relation to late VKDB pathogenesis.
• To highlight the limitations of conventional tests and the utility of biomarkers like PIVKA-II.
• To emphasize the need for extended vitamin K supplementation in high-risk infants.

Main Methods:

• Literature review focusing on vitamin K metabolism, VKDB, and diagnostic markers.
• Analysis of factors contributing to late VKDB, including nutritional and physiological aspects.
• Evaluation of current prophylaxis strategies and their limitations.

Main Results:

• Subclinical vitamin K deficiency can be detected using biomarkers such as PIVKA-II.
• Late VKDB occurs due to declining vitamin K levels and nutritional factors post-birth prophylaxis.
• Conventional coagulation tests have limitations in identifying early deficiency.

Conclusions:

• Prolonged vitamin K supplementation is necessary for high-risk newborns to prevent late VKDB.
• Daily oral vitamin K (150 µg/day) is recommended for exclusively breastfed infants.
• Vitamin K-containing multivitamins may benefit preterm infants to ensure adequate status.