Reduced TNFalpha and IL-6 production in patients who mount a preoperative acute phase response

In some patients postoperative infective complications are related to a reduced resistance to the operative trauma and the perioperative microbiological challenge. To investigate preoperative alterations in the immune responses in patients who had mounted an acute-phase response before the operation, we measured the capacity of tumor necrosis factor alpha and interleukin-6 production in whole blood.

Serum concentrations of C-reactive protein, alpha1-antitrypsin, albumin, and prealbumin were measured in 89 patients submitted for major abdominal surgery on their admission to hospital.

In 23 patients (26%) we found concentrations of at least one, and in 16 patients (18%) of two or more of these variables beyond the reference range. Patients who mounted an acute-phase response released 37% less TNFalpha (1339 vs. 848 pg/ml) and 31% less IL-6 (24293 vs. 16900 pg/ml) when whole blood was stimulated with lipopolysaccharide 0.5 microg/ml.

Patients who mount an acute-phase response before operation may thus have a downregulated immune response at the level of proinflammatory cytokines. This is likely to alter their resistance to invasive micro-organisms in the perioperative period.