Plasma homocysteine concentrations of preterm infants

Mild hyperhomocysteinemia in adults is associated with an increased risk of vascular disease. Although information is available about plasma homocyste ine concentrations in childhood, data are entirely lacking for preterm infa nts despite their known abnormalities of sulfur amino acid metabolism. We m easured plasma total homocysteine concentrations of 9 preterm infants (gest ational age 23-31 weeks) within 48 h of birth and over the subsequent 14 da ys of life, and 4 term infants (gestational age 36-39 weeks) on a single oc casion within 72 h of birth, As measured within 48 h of birth, average plas ma homocysteine and cysteine concentrations of the preterm infants were 3.8 +/- 0.3 and 122 +/- 8 mu M, both significantly less than those of the term infants (6.1 +/- 1.3 and 187 +/- 39) and of normal adults (8.2 +/- 0.5 and 232 +/- 6), Plasma homocysteine (but not cysteine) appeared to gradually i ncrease during the first 2 weeks of life (p = 0.053). Our results indicate that hyperhomocysteinemia does not normally occur in preterm infants.