Peritoneal fluid cytokines and matrix metalloproteinases as early markers of anastomotic leakage in colorectal anastomosis: a literature review and meta‐analysis

AIM: There has been recent interest in the measurement of peritoneal fluid cytokines in the early postoperative period to help diagnose anastomotic leakage at a preclinical stage. The currently available literature on the early diagnosis of colorectal anastomotic leakage by estimation of drain fluid cytokines or matrix metalloproteinases (MMP) is reviewed. METHOD: A literature search was performed in PubMed, EMBASE and the Cochrane library for all publications studying the feasibility of diagnosing colorectal anastomotic leakage earlier by estimation of peritoneal fluid cytokine or MMP levels. A meta-analysis of the most commonly measured cytokines was performed. RESULTS: Eight publications were included. Tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were most frequently studied. Most studies found significantly higher levels of TNF-α and IL-6 in patients with anastomotic leakage during the first three postoperative days. In the meta-analysis IL-6 levels were significantly higher from day 1 and TNF-α from day 2. MMP-9 was most often significantly elevated in patients with anastomotic leakage. CONCLUSION: Measurement of drain fluid cytokines and MMP has the potential to diagnose colorectal anastomotic leakage at a preclinical stage, but is not yet ready for clinical use. Further research is needed, possibly using IL-6 in combination with other cytokines and MMP as markers.