The Clinical Relevance of an Inflamed Appendix in Crohn's Disease

Background and Aims An appendectomy for appendiceal inflammation has been suggested to ameliorate the clinical course of patients with ulcerative colitis [UC]. In contrast, for Crohn's disease [CD] an inverse association has been suggested with a higher incidence of CD and worse prognosis after appendectomy. The aim of this study was to analyse the clinical relevance of an inflamed appendix in CD patients undergoing ileocaecal resection [ICR].Methods All consecutive patients undergoing primary ICR between 2007 and 2018 were considered for inclusion. Microscopic data of available appendiceal resection specimens [n = 99] were revised by a dedicated inflammatory bowel disease [IBD] pathologist and scored as inflamed or not inflamed. Eighteen patients had a previous appendectomy. Pathological findings were correlated with disease characteristics and recurrence rates [clinical, endoscopic, and intervention-related].Results In total 117 patients were included, 77 [65.8%] females, with a median age of 30 years (interquartile range [IQR] 24-43), and a median follow up of 102 months [IQR 76-114]. Of patients without previous appendectomy [n = 99], 39% had an inflamed appendix. No significant differences in disease characteristics [eg, disease location, behaviour, time to surgery] or prognosis could be demonstrated between the two groups. In contrast, previous appendectomy [n = 18] was associated with penetrating disease and numerically shorter disease duration at the time of resection. Furthermore, a trend was seen towards a stronger association with postoperative recurrence.Conclusion The current study could not confirm a different prognosis for CD patients with and without an inflamed appendix. In contrast, in patients with a previous appendectomy, a trend was seen towards increased postoperative recurrence, which might be related to the higher incidence of penetrating disease.