To investigate the expression of Th17-related factors, sICAM-1 and MMP-12 in patients with postoperative infection and diabetes mellitus after colorectal cancer surgery.

From August 2015 to August 2018, clinical data of 117 patients with type 2 diabetes mellitus who underwent radical resection of colorectal cancer were analyzed retrospectively. ROC curve was used to analyze the predictive value of IL-17, sICAM-1 and MMP-12 for postoperative infection. SPSS 22.0 statistical software was used for data analysis. Th17 and Treg cell level were expressed as (±s) and were examined by independent t test. ROC curve was used to analyze the predictive value of IL-17, sICAM-1 and MMP-12 for postoperative infection. A P value of <0.05 was considered as statistically significant.

Among the 117 patients, postoperative infection occurred in 31 cases(26.5%). There were 38 strains of pathogenic bacteria in 31 patients with postoperative infection, including 24 strains of Gram-negative bacteria (63.2%), 13 strains of Gram-positive bacteria (34.2%) and 1 strain of fungi (2.6%). Th17 and Th17/Treg in peripheral blood of infected group were significantly higher than those of uninfected group (P<0.05). Treg cells in peripheral blood of infected group were significantly lower than those of uninfected group (P<0.05). The levels of serum IL-17, sICAM-1 and MMP-12 in the infection group were significantly higher than those in the non-infected group respectively(P<0.05). ROC curve was used to analyze the predictive value of IL-17, sICAM-1 and MMP-12 for postoperative infection. The scores under each index curve were 0.814, 0.867 and 0.742 respectively (P<0.05).

The postoperative infection in patients with colorectal cancer and diabetes could cause imbalance of Th17/Treg, triggers the autoimmune response and inflammation, elevate the level of serum IL-17、sICAM-1 and MMP-12.The indexes of serum IL-17、sICAM-1 and MMP-12 could be used as the early diagnostic indexes for postoperative infection.