REACH: C-cause

Inflammatory bowel disease (IBD) arises from a multifaceted interplay of genetic predisposition, environmental triggers, microbial dynamics, and immune dysregulation. This complex network of interacting factors disrupts gut homeostasis, leading to chronic relapsing inflammation in the gastrointestinal tract. This review synthesizes the current understanding of the multifactorial causes of IBD. Central to disease pathogenesis is the altered relationship between the host immune system and the intestinal microbiome, which culminates in a persistent cycle of tissue damage and inflammation, involving both innate and adaptive immunity as well as non-immune cells. Efforts to elucidate these integrated pathways have underscored the importance of both intrinsic host factors and extrinsic environmental triggers in IBD pathogenesis. Despite this, a better understanding of disease mechanisms is still needed, and will be essential to developing better therapies that can target relevant axes of the disease process and restore immune balance, facilitate tissue repair, and induce lasting remission.