Related Experiment Video
Updated: Jun 21, 2026
13:13
Biochemical Measurement of Neonatal Hypoxia
Published on: August 24, 2011
Plasma aminotransferase concentrations in preterm infants
S Victor1, H Dickinson, M A Turner
1Neonatal Medical Unit, St Mary's Hospital for Women and Children, Whitworth Park, Manchester, UK. suresh.victor@manchester.ac.uk
Summary
New reference ranges for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were established for preterm infants. Extremely premature babies showed higher enzyme levels, potentially linked to immediate postnatal illness severity.
Area of Science:
- Neonatal Medicine
- Clinical Biochemistry
- Pediatric Research
Background:
- Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) are critical liver enzymes.
- Establishing accurate reference ranges for these enzymes in preterm infants is essential for clinical management.
- Preterm infants present unique physiological challenges that may affect enzyme levels.
Purpose of the Study:
- To generate reference ranges for AST and ALT in preterm infants.
- To describe plasma concentrations of AST and ALT in infants born between 22 and 36 weeks' gestation.
- To compare enzyme activities across different gestational ages in preterm neonates.
Main Methods:
- A service evaluation was performed in two UK neonatal intensive care units.
- Data from 7006 blood samples collected between 2004 and 2008 were analyzed.
- Infants born between 22 and 36 weeks' gestation were included in the study.
Main Results:
- Reference ranges for AST and ALT were successfully generated for preterm infants.
- Extremely premature infants (earlier gestational age) exhibited significantly higher plasma AST and ALT activities.
- A correlation between higher enzyme activity and earlier corrected gestational age was observed.
Conclusions:
- The study provides crucial reference ranges for AST and ALT in preterm neonates.
- Higher enzyme levels in extremely premature infants may indicate greater illness severity shortly after birth.
- These findings aid in the interpretation of liver enzyme tests in this vulnerable population.
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