Neutrophil dysfunction in steroid-overdosed patients with ulcerative colitis: potential relevance of macrophage migration inhibitory factor to increased postoperative morbidity.

PURPOSE

We studied macrophage migration inhibitory factor (MIF)-related neutrophil dysfunction in patients with ulcerative colitis (UC), under conditions of surgical stress, focusing in particular on total preoperative steroid dosages.

METHODS

Neutrophils were isolated from peripheral blood samples obtained from 21 UC patients soon after radical surgery for UC. The patients were divided into two subgroups according to their total preoperative prednisolone dosages. The neutrophil phagocytosis, viable cell, and cell necrosis rates after exposure to Escherichia coli were evaluated by flow cytometry. The supernatant concentrations of mediators after exposure to E. coli were evaluated by enzyme-linked immunosorbent assay.

RESULTS

There was a significant positive correlation between the levels of MIF and the total preoperative dosage of prednisolone. More viable neutrophils from the high-dosage steroid group patients than from the low-dosage steroid group patients tended to undergo necrosis, followed by the release of neutrophil elastase after exposure to E. coli. The levels of anti-inflammatory cytokines were not enhanced after E. coli stimulation, but the levels of proinflammatory cytokines in the supernatants of neutrophils from the high-dosage steroid group patients were increased significantly.

CONCLUSION

Steroid-overdosed UC patients with MIF-related neutrophil dysfunction may be at increased risk of destructive local inflammation following surgery.