Acylcarnitine profiles of preterm infants over the first four weeks of life
Related Experiment Video
Updated: Sep 22, 2026
Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale
Published on: August 25, 2014
Jochen Meyburg1, Andreas Schulze, Dirk Kohlmueller
1Department of Neonatology, Division of Metabolic and Endocrine Diseases, University Children's Hospital, Im Neuenheimer Feld 150, 69120 Heidelberg, Germany. jochen_meyburg@med.uni-heidelberg.de
Insights
Acylcarnitine profiles in preterm infants show higher initial levels compared to full-term neonates. These levels decrease over time, but metabolite ratios remain useful for detecting inborn errors of metabolism.
Area of Science:
- Biochemistry
- Neonatology
- Metabolomics
Background:
- Neonatal screening relies on acylcarnitine measurements for detecting inborn errors of metabolism.
- Limited data exists on acylcarnitine profiles in premature infants during early life.
Purpose of the Study:
- To investigate longitudinal changes in acylcarnitine profiles of preterm and full-term neonates.
- To assess the impact of gestational age on carnitine and acylcarnitine levels in the first four weeks of life.
Main Methods:
- Studied 120 infants across four gestational age groups (22-41 weeks).
- Collected blood samples on Guthrie cards at multiple time points (days 1, 3, 5, 7, 14, and 28).
- Analyzed carnitine and acylcarnitines using electrospray ionization tandem mass spectrometry.
Main Results:
- Postnatally, very preterm infants (22-27 weeks) had significantly higher free carnitine and acylcarnitine concentrations than full-term infants.
- Carnitine levels decreased from day 1 to day 7 in the most premature groups, with partial recovery by day 14.
- By day 28, carnitine levels in preterm infants decreased further or normalized to postnatal levels.
Conclusions:
- Postnatal carnitine levels are elevated in very immature preterm infants but decrease by day 28.
- Despite dynamic changes, standard metabolite ratios are likely sufficient for diagnosing inborn errors of metabolism in preterm neonates.
Abstract:
Measurement of free carnitine and acylcarnitines allows the detection of several inborn errors of metabolism in neonatal screening. Because available data for premature infants is limited, we studied longitudinal changes in acylcarnitine profiles of full-term and preterm neonates over the first 4 weeks of life. One hundred twenty infants were divided into four groups of 30: A, gestational age 22 to 27 wk; B, 28 to 31 wk; C, 32 to 36 wk; and D, 37 to 41 wk. Blood samples spotted on a Guthrie card were taken on days 5 and 28. Additional specimens (groups A and B only) were collected on days 1, 3, 7, and 14. Carnitine and its acyl esters were detected by looking for the precursor ions of m/z = 85 using a PE Sciex API 365 electrospray ionization tandem mass spectrometer. Concentrations of free carnitine and most acylcarnitines were significantly higher in group A compared with group D postnatally. Groups B and C displayed intermediate values. Carnitine levels in infants from group A and B decreased steadily from day 1 to day 7, and recovered up to day 14 in group B only. On day 28 carnitine concentrations had further decreased in group A, while reaching postnatal levels again in group B. Postnatal carnitine levels are higher in very immature preterm infants compared with full-term infants, but become lower on day 28. However, the commonly used metabolite ratios should still allow the detection of inborn errors of metabolism.
More Related Videos
07:36Modeling Encephalopathy of Prematurity Using Prenatal Hypoxia-ischemia with Intra-amniotic Lipopolysaccharide in Rats
Published on: November 20, 2015
08:58Development of a Neonatal Piglet Acute Lung Injury Model Recreating the Early Environment of Preterm Infant Lungs
Published on: October 31, 2025
