Presented at the Neonatal Society 2001 Summer Meeting.

Besheya TA¹, Clarke P², Reed P¹, Kane J¹, Weinkove C¹

¹ University of Manchester, Department of Medicine (Clinical Biochemistry), Clinical Sciences Building, Hope Hospital, Salford, M6 8HD, UK
² Neonatal Intensive Care Unit, Hope Hospital, Salford, M6 8HD, UK

Background: Increased susceptibility to infection and growth failure are common complications of prematurity, yet also features of Essential Fatty Acid (EFA) deficiency (1). Preterm infants may be born with poorer EFA status compared with term infants (2) and this could render them more prone to these complications.

Aims: To determine whether preterm infants are deficient in EFAs at birth by comparing the fatty acid content of erythrocytes in full-term and preterm infants; to assess if measurement of the EFA content of erythrocytes might be used as an indicator of the nutritional status of preterm neonates.

Methods: Venous blood samples were collected on the first postnatal day from preterm infants admitted to the Neonatal Unit and cord blood samples were obtained at birth from full-term neonates. Erythrocyte EFA concentrations were measured by an isocratic HPLC method using fluorimetric detection, after separation on a C-8 Spherisorb column (3).

Results: 19 preterm infants with median gestation 30 weeks [range 25 – 36] and 20 full-term infants with median gestation 39 weeks [range 37 – 41] were studied.

Erythrocyte fatty acid concentrations are expressed in mmol/1012 RBC.

Conclusions: Excepting eicosatrienoic acid, all erythrocyte EFA concentrations were unexpectedly higher for preterm infants. The greater concentration of maternally-derived fatty acids in erythrocytes of premature infants may reflect a higher demand for EFAs in the preterm fetus. Our analysis of erythrocyte EFA content does not provide evidence for congenital EFA deficiency in preterm neonates. These observations preclude the use of erythrocyte EFA concentrations as an index of neonatal nutritional status.

References
1. Paulsrud JR, Pensler L, Whitten CF, Stewart S, Holman RT. Am J Clin Nutr 1972;25:897-904
2. Leaf AA, Leighfield MJ, Costeloe KL, Crawford MA. J Pediatr Gastroenterol Nutr 1992;14:300-8
3. Besheya TA, Reed P, Kane J, Weinkove C. Proceedings of the ACB National Meeting 1998:p34