Concentrations of cytokines in plasma of patients with large burns: their relation to time after injury, burn size, inflammatory variables, infection, and outcome.

OBJECTIVE: To monitor longitudinally the concentrations of cytokines in the plasma of patients with severe burns.

DESIGN: Prospective open study.

SETTING: Burns unit, university hospital, Norway.

SUBJECTS: 27 patients (5 women and 22 men, mean age 37 (range 13-82) years).

INTERVENTIONS: Measurement of plasma concentrations of interleukin-1beta(IL-1beta), interleukin-1 receptor antagonist (IL-1ra), interferon-7(IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) were measured by enzyme linked immunosorbent assays (ELISA).

MAIN OUTCOME MEASURES: Changes in concentrations, and correlation with morbidity and mortality.

RESULTS: The concentration of IL-1beta and IL-1ra were increased in all patients and highest at the time of admission. Initially there was little or no circulating IFN-gamma, but this increased from day 5-10 in all patients. Only 8/15 patients had transient increases in circulating TNF-alpha. Concentrations of IL-1ra correlated with total burn surface area (TBSA) and area of third degree burn, as well as with plasma concentrations of C - reactive protein (CRP). Concentrations of IL-1beta and IL-1ra were higher in patients who developed infective complications than in those who did not (interleukin-8 (IL-8) has previously been shown to follow this pattern as well). Patients who survived had significantly higher IL-1beta concentrations than those who died (13(1) compared with 3 (1) pg/ml, p = 0.005)

CONCLUSION: There are significant time-dependent changes in plasma concentrations of IL-1beta, IL-1ra, IFN-gamma and TNF-alpha after serious burns. IL-1ra concentrations may be influenced by size of the burn and the acute phase response; IL-1beta, IL-1ra and IL-8 may have a role in the host's response to infection; and IL-1beta may influence outcome.