Abstract
Anastomotic leakage (AL) is a major complication of colorectal surgery that can lead to abdominal infection and systemic inflammatory response. Meanwhile, the microbiota and immune microenvironment at the anastomosis are closely related to the formation of AL. Presently, a considerable volume of research is directed toward investigating the colorectal microenvironment in AL. These studies offer a robust foundation for probing etiological factors contributing to the AL. This is the first review to comprehensively depict the bidirectional effects of intestinal immunity and microbiota on anastomotic healing. Furthermore, this study also elaborates on the association between the clinical risk factors and micro-mechanisms of AL, and provides a novel perspective for its early diagnosis.