Dynamics of blood cytokine concentrations in patients with bacteremic infections

Cytokines play a major role in the pathophysiology of sepsis and septic shock. Using enzyme immunoassays the acute serum levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), granulocyte-colony stimulating factor (G-CSF), interleukin-8 (IL-8), and leukemia inhibitory factor (LIF) were investigated in 90 patients with positive blood cultures and clinical signs of infection. In 27 patients samples were obtained on admission, after 1, 4, 12, 18, and 24 h, and then daily. The acute serum levels of IL-6, TNF-alpha, G-CSF, and IL-8 were significantly higher among patients with severe sepsis. Patients with Gram-negative infection had significantly higher levels of TNF-alpha on admission than did patients with Gram-positive infections (p=0.0008). The levels of IL-6, G-CSF and, to some extent, TNF-alpha decreased rapidly in survivors within the first 24 h of admission to hospital and institution of treatment. LIF was detected in 8/90 in both survivors and nonsurvivors.