The state of the immune system in abdominal sepsis

Sepsis is a serious condition characterized by a complex dysfunction of internal organs and systems. In the basis of the pathogenesis of sepsis, the leading role is played by the dysregulation of the immune response to the infectious agent, in particular endotoxin of gramnegative bacteria, which is an obligate lipopolysaccharide of the bacterial wall. Aim. To evaluate the prognostic value of cytokine profile, phagocytosis activity indices, endotoxin concentration and activity in blood in gram-negative sepsis. Materials and methods. 78 patients with abdominal sepsis were included in a one-center prospective cohort study, of them 45 died. All the patients were evaluated for the concentration of circulating cytokines (TNF-α, IFN-γ, IL-6, IL-8, IL-10), cellular molecules (CD3, CD45RO, CD95 and HLA-DR), bactericidal and phagocytic activity of neutrophils and endotoxin (lipopolysaccharide) level in peripheral blood. Results and discussion. The concentrations of all cytokines were slightly lower in the survivors. Significant differences were noted for TNF-α (p=0.001), IL-6 (p=0.001), and IL-8 (p=0.007). The expression of HLA-DR molecules was slightly higher (p=0.055), and CD95 was lower (p=0.146) in survivors than in the dead. However, the differences have not reached the required level of statistical significance. The phagocytic (p<0.001) and bactericidal activity (р=0.002 for stimulated activity and p=0.001 for spontaneous activity) of neutrophils is significantly different. In survived patients, we noted large values of stimulated bactericidal activity and phagocytic index than the dead. Level of spontaneous activity in survivors was lower. In subsequently deceased patients, the level of endotoxin load was higher than in the surviving patients: level of lipopolysaccharide concentration (p=0.002), endotoxin activity (p=0.032) and neutrophils activity (p=0.028). Conclusion. Evaluation of cytokine levels is informative, but due to the high spread of indicators in different patients, should be carried out in the dynamics. The most informative prognostic parameters in sepsis are the concentration and activity of lipopolysaccharides (endotoxin), phagocytic and bactericidal activity of neutrophils. The EAA (endotoxin activity assay) assessment should be conducted in conjunction with the neutrophil "response" assessment.