Immunoparalysis and nosocomial infection in children with multiple organ dysfunction syndrome.

PURPOSE

Immunoparalysis defined by prolonged monocyte human leukocyte antigen DR depression is associated with adverse outcomes in adult severe sepsis and can be reversed with granulocyte macrophage colony-stimulating factor (GM-CSF). We hypothesized that immunoparalysis defined by whole-blood ex vivo lipopolysaccharide-induced tumor necrosis factor-alpha (TNFα) response <200 pg/mL beyond day 3 of multiple organ dysfunction syndrome (MODS) is similarly associated with nosocomial infection in children and can be reversed with GM-CSF.

METHODS

In study period 1, we performed a multicenter cohort trial of transplant and nontransplant multiple organ dysfunction syndrome (MODS) patients (≥2 organ failure). In study period 2, we performed an open-label randomized trial of GM-CSF therapy for nonneutropenic, nontransplant, severe MODS patients (≥3 organ failure) with TNFα response <160 pg/mL.

RESULTS

Immunoparalysis was observed in 34% of MODS patients (n = 70) and was associated with increased nosocomial infection (relative risk [RR] 3.3, 95% confidence interval [1.8-6.0] p < 0.05) and mortality (RR 5.8 [2.1-16] p < 0.05). TNFα response <200 pg/mL throughout 7 days after positive culture was associated with persistent nosocomial infection, whereas recovery above 200 pg/mL was associated with resolution of infection (p < 0.05). In study period 2, GM-CSF therapy facilitated rapid recovery of TNFα response to >200 pg/mL by 7 days (p < 0.05) and prevented nosocomial infection (no infections in seven patients versus eight infections in seven patients) (p < 0.05).

CONCLUSIONS

Similar to in adults, immunoparalysis is a potentially reversible risk factor for development of nosocomial infection in pediatric MODS. Whole-blood ex vivo TNFα response is a promising biomarker for monitoring this condition.