Author response to: Comment on: Prospective cohort study of appendicectomy for treatment of therapy‐refractory ulcerative colitis

Abstract

Editor We thank Dai and Jiang for their interesting comment regarding our paper analysing the effect of appendicectomy in patients with refractory ulcerative colitis (UC)1. Indeed, several studies suggest that appendicectomy before the age of 20 years protects against the development of UC, especially when performed for appendicitis. However, it is difficult to compare previous epidemiological results with the current data looking at the therapeutic role of appendicectomy in established UC, which is a fundamentally different patient group. In this therapeutic context, the results are comparable to the only other prospective study by Bolin et al.2, who demonstrated a therapeutic effect of appendicectomy in 27 of 30 patients with ulcerative proctitis. Interestingly, the previously published short-term results of the current study showed that pathological response (in biopsies at endoscopy 3 months after appendicectomy) was related to active appendiceal inflammation, limited disease (proctitis) and younger patients with shorter disease duration3. Although no other human studies exist comparing pathological therapeutic results to patient or appendix characteristics, these findings are in line with murine models demonstrating a beneficial effect of appendicectomy at younger age4. Therefore, we conclude that our results do not fundamentally differ from previously published studies. The mechanistic link between appendicectomy and the prevention of UC, as well as its therapeutic effect in patients with established UC, is still unknown. However, it seems likely that inflammation of the appendix and patient age (or disease duration) do play a role. The challenge for future research will be to identify a patient group most likely benefitting from appendicectomy to tailor treatment options for patients with this chronic disease.