Outcomes and endpoints of postoperative recurrence in ileocaecal Crohn's disease

Crohn’s disease (CD) is a chronic inflammatory bowel disease in which surgery is often required and postoperative recurrence remains common. This thesis, entitled Outcomes and Endpoints of Postoperative Recurrence in Ileocaecal Crohn’s Disease, aimed to improve the (surgical) care of patients with ileocaecal CD by providing insight into postoperative disease recurrence, identifying which patients benefit most from upfront surgery, and evaluating the value of both traditional and emerging risk factors for postoperative outcomes.
Part I focuses on postoperative recurrence after ICR. Although recurrence rates have declined over time, they remain considerable. The 10-year follow-up of the LIR!C trial showed that upfront ICR resulted in higher rates of therapy-free remission than infliximab, supporting surgery as an effective early treatment option for selected patients with uncomplicated ileocaecal CD. Surgical factors may also influence postoperative outcomes, and ongoing international randomized trials are investigating whether anastomotic configuration can reduce recurrence. Reliable assessment of endoscopic recurrence is essential, as substantial disagreement between local and central readers resulted in clinically relevant misclassification.
Part II investigates the role of the mesentery. In ulcerative colitis (UC) patients undergoing pouch surgery, a pro-inflammatory mesorectal macrophage profile was associated with inflammatory disorders of the pouch. Pro-inflammatory macrophages showed increased expression of the calprotectin-encoding genes S100A8 and S100A9, identifying mesenteric calprotectin as a potential surrogate marker of a pro-inflammatory immune profile. These emerging insights into the immunological role of the mesentery may improve patient selection, postoperative risk stratification, and personalised surgical management in both CD and UC