Whole-body leucine kinetics and the acute phase response during acute infection in marasmic Malawian children

Pediatr Res. 2004 Jun;55(6):940-6. doi: 10.1203/01.pdr.0000127017.44938.6d.

Abstract

This study compared leucine kinetics and acute-phase protein and cytokine concentrations in three groups of Malawian children who were fed an isoenergetic, isonitrogenous diet: children with marasmus with (n = 25) and without (n = 17) infection and well-nourished children with infection (n =13). The hypotheses tested were that whole-body leucine kinetics will be less in marasmic acutely infected children than in well-nourished acutely infected children but greater than in marasmic uninfected children. Children were studied after 24 h of therapy using standard (13)C-leucine stable isotope tracer techniques. Well-nourished children with acute infection had greater leucine kinetic rates than did marasmic children with acute infection; nonoxidative leucine disposal was 153 +/- 31 versus 118 +/- 43 micromol leucine. kg(-1). h(-1), leucine derived from whole-body proteolysis was 196 +/- 34 versus 121 +/- 47, and leucine oxidation was 85 +/- 31 versus 45 +/- 13 (p < 0.01 for all comparisons). Leucine kinetic rates were similar in marasmic children with and without acute infection. Well-nourished children with acute infection increased their serum concentration of five of six acute-phase proteins during the first 24 h, whereas marasmic children with infection did not have any increases. The serum concentrations of IL-6 were elevated in well-nourished and marasmic children with infection. These data suggest that the cytokine stimulus for the acute-phase protein kinetic response to acute infection is present in marasmic children but that the acute-phase protein metabolic response is blunted by malnutrition.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acute Disease
  • Acute-Phase Proteins / metabolism
  • Acute-Phase Reaction / complications*
  • Acute-Phase Reaction / metabolism*
  • C-Reactive Protein / metabolism
  • Carbon Isotopes
  • Child, Preschool
  • Cytokines / blood
  • Female
  • Humans
  • Infant
  • Infections / complications*
  • Infections / metabolism*
  • Interleukin-6 / blood
  • Leucine / pharmacokinetics*
  • Malawi
  • Male
  • Protein-Energy Malnutrition / complications*
  • Protein-Energy Malnutrition / metabolism*

Substances

  • Acute-Phase Proteins
  • Carbon Isotopes
  • Cytokines
  • Interleukin-6
  • C-Reactive Protein
  • Leucine