Effect of sepsis syndrome on neonatal protein and energy metabolism

OBJECTIVE: It was our hypothesis that septic illness would alter both protein and energy metabolism in neonates, with elevations of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) serving as markers for these effects. STUDY DESIGN: A total of 31 infants with suspected sepsis were enrolled into four groups: septic, sick-nonseptic, healthy-nonseptic, and recovered septic infants. Degree of illness, oxygen consumption, nitrogen balance, urine 3-methylhistidine/creatinine (MeH/Cr), and TNF-α, IL-6, IL-1β, and C-reactive protein (CRP) were measured. RESULTS: Oxygen consumption increased, while nitrogen balance decreased and MeH/Cr increased with increasing degree of illness. Nitrogen balance improved on recovery from sepsis. IL-6 and CRP levels were elevated in septic infants compared with sick-nonseptic and healthy infants. CONCLUSION: Neonates experience a hypermetabolic response with increased nitrogen loss during septic illness, proportional to the degree of illness. Increased delivery of protein substrate may be nutritionally advantageous to the septic neonate.