LAUSR

Objective Ulcerative colitis (UC) is a chronic inflammatory disease of the large intestine. At present, the significance of appendiceal orifice inflammation (AOI) in UC prognosis is still controversial. This prospective observational study investigated the importance of AOI in UC diagnosis and prognosis. Additionally, it compared the therapeutic efficacy of treatments in UC patients with or without AOI. Design This study was a prospective, observational, single-centre, real-world study. Patients with AOI were included in the observation group, and patients without AOI were assigned to the control group. All patients were followed up for 1 year; the disease remission and treatment efficacy were re-examined by colonoscopy. In addition, the clinical, endoscopic and pathological features were collected before and after the treatment. Results Patients with endoscopic diffuse inflammatory changes in the distal colorectum accompanied by AOI had a higher positive UC diagnosis rate than those without (96.5% vs 78.0%). Also, AOI had a specificity of 95.2% and a sensitivity of 28.3% for UC diagnosis. However, no difference in the modified Mayo score (p=0.881) or Baron grading was observed between the control and observation groups, indicating that AOI does not affect the treatment outcome of UC patients. Conclusion In this study, the observation of AOI improved the UC diagnostic accuracy in patients with diffuse lesions in the distal colorectum. Furthermore, the presence of AOI does not affect the treatment efficacies of UC. Trial registration number ChiCTR1800017753.