ARS | Publication request: Parenteral sulfur amino acid requirements in septic infants

Submitted to: Journal of Federation of American Societies for Experimental Biology
Publication Type: Abstract Only
Publication Acceptance Date: February 1, 2007
Publication Date: March 1, 2007
Citation: Sy, J., Gordon, W., Griffin, D., Jefferson, L.S., Krance, R.A., Heird, W., Castillo, L. 2007. Parenteral sulfur amino acid requirements in septic infants [abstract]. Journal of Federation of American Societies for Experimental Biology. 21(6):A1072.

Technical Abstract: To investigate parenteral methionine requirements of critically ill, septic infants, we conducted an investigation involving 12 infants (age 2+/-1 years; weight 13+/-2kg) using the intravenous indicator amino acid oxidation and balance technique. They received a balanced parenteral amino acid formula supplying a cysteine intake at 36 mg.kg–1.d–1. They were randomized to 1 of 6 different methionine intakes. Total amino acid and energy intakes were 2+/-0.3g.kg–1.d–1 and 59+/-13 kcal/kg–1.d–1. After adaptation to the assigned methionine intake for at least 24 h, an L-[1-13C] leucine tracer was given as a primed, 6h continuous, intravenous infusion. Leucine balance was negative at methionine intakes of 20 and 24 mg.kg–1.d–1 (p<0.05) and total sulfur amino acid (TSAA) intakes of 56 and 60 mg.kg–1.d–1. Leucine balance was positive at methionine intakes of 28, 35, 41, and 45 mg.kg–1.d–1, and TSAA intakes of 64, 71, 77 and 81 mg.kg–1.d–1. Methionine requirement of critically ill infants appears to be at least 27 mg.kg–1.d–1, at cysteine intakes of 36 mg.kg–1.d–1.