Granulocyte elastase and systemic cytokine response after laparoscopic-assisted and open resections in Crohn's disease

PURPOSE: The aim of this study was to assess whether systemic proinflammatory cytokines (IL-6), anti-inflammatory cytokines (IL-4, IL-10), acute phase proteins (C-reactive protein), or granulocyte elastase are valuable indicators for determining the degree of surgical trauma after open vs. laparoscopic-assisted resections in Crohn's disease. METHOD: Eleven patients in each group (open and laparoscopic-assisted surgery) mere matched for indication, surgical procedure, and Crohn's disease activity index. Serum IL-4, IL-6, and IL-10 were measured using enzyme-linked immunosorbent assay. Serum C-reactive protein was determined by immunoturbidimetric assay. Plasma granulocyte elastase was determined by immunoactivation immunoassay. Blood was sampled preoperatively, six hours after the operation, and at postoperative Days 1 to 5. RESULTS: IL-4 was not detectable in any sample analyzed. Serum IL-6 and IL-10 levels peaked postoperatively in both groups without significant differences between laparoscopic-assisted (185.6 +/- 54.1 pg/ml and 112.1 +/- 19.4 pg/ml, respectively; mean +/- standard error of the mean) and open surgery (431.1 +/- 240.4 pg/ml and 196.7 +/- 56.5 pg/ml, respectively). Serum C-reactive protein levels also rose postoperatively with a peak on the second day, but showed similar values after laparoscopic-assisted (107.1 +/- 12.1 mg/l) and open (128.3 +/- 17.5 mg/l) surgery. Plasma granulocyte elastase levels peaked on the first and second postoperative day and were found elevated almost throughout the five-day observation period. Comparison between the groups revealed significantly (P < 0.02) lower values after laparoscopic-assisted (Day 1, 46.5 +/- 8.9 mu g/l; Day 2, 41.9 +/- 5.9 mu g/l) when compared with open surgery (Day 1, 89.7 +/- 13.8 mu g/l; Day 2, 91.4 +/- 14). CONCLUSIONS: Serum IL-6 and IL-10 may not be ideal measures for evaluation of the degree of tissue trauma in laparoscopic-assisted and open resections in Crohn's disease, probably because of interference with disease-specific cytokine interactions. In contrast, granulocyte elastase has to be considered a strong marker discriminating the different severity of surgical trauma induced by laparoscopic-assisted vs. open resection in Crohn's disease.