Levels of portal and systemic blood cytokines after colectomy in patients with carcinoma or Crohn's disease

Abstract

Background: Cytokine overproduction has been observed in different pathophysiologic conditions, including sepsis, carcinoma, inflammatory disease, and tissue injury induced by operation. Colectomy is a procedure that may result in excessive cytokine release through the portal vein. The respective effects of an operative procedure, perioperative septic complications, and of the disease itself on cytokine production are still not known.

Study design: This study was done to investigate the variations in the levels of interleukin-1 beta (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein (CRP) in portal and systemic blood during and after colectomy in patients with malignancy or with Crohn's disease. Blood samples were collected intraoperatively from portal and systemic veins of 24 patients undergoing colectomy for either Crohn's disease (n = 13) or carcinoma (n = 11), and postoperatively (from days 1 to 5) from systemic veins. The changes in blood levels of cytokines and CRP in patients with an uneventful colectomy (n = 19) were compared to changes in patients whose colectomy was complicated by sepsis (n = 5). Similar changes in cytokines and CRP levels were compared between patients with malignancy and those with Crohn's disease.

Results: The portal and systemic blood levels of IL-1, IL-6, TNF-alpha, and CRP were significantly correlated before and after colectomy. In portal blood, the level of IL-6 was significantly higher after colectomy than before. In systemic blood, the levels of CRP, TNF-alpha, and IL-6 before colectomy were significantly higher in patients with Crohn's disease than in patients with malignancy. After uneventful colectomy, a temporary increase in CRP, TNF-alpha, and IL-6 was noted in systemic blood, followed by a rapid decrease, although systemic blood cytokine levels remained significantly higher after colectomy complicated by sepsis. Interleukin-1 beta levels in both portal and systemic blood remained unchanged during and after colectomy, regardless of the indication for operation and its outcome.

Conclusions: Colectomy causes acute release of cytokines and CRP in both the portal and systemic circulation. The increase in IL-6 observed after colectomy in portal blood and subsequently in systemic blood suggests local production from the resected specimen, or at least from the area of resection. Cytokine production, especially of IL-6, was modified not only by the underlying disease itself, as higher levels were observed in Crohn's disease before colectomy, but also by the presence of perioperative septic complications.