Moynihan Prize 1 Antibiotic management of acute appendicitis avoids surgery in over 70% of adults: one-year follow-up from a prospective, multicentre, observational study

Abstract

Abstract Background Surgeons are sometimes reluctant to manage uncomplicated appendicitis non-operatively. Reasons cited are unknown rates of recurrent appendicitis and the risk of missed appendiceal malignancy. The aim of this study was to address these uncertainties and determine the long-term efficacy of antibiotic versus operative management of appendicitis. Method One-year follow-up of patients enrolled in the multicentre observational COVID:HAREM cohort study during March-June 2020 was undertaken. Patients were diagnosed with appendicitis either clinically or radiologically; initial operative or non-operative management was determined on a case-by-case basis by the responsible surgeon. Outcomes were the one-year appendicectomy rate, resected appendix histology and predictors of antibiotic failure. Results A total of 625 patients who underwent non-operative management were identified from 49 of the original 97 hospital sites. The overall appendicectomy rate at one-year in the initial non-operative group was 29% (180/625), with a median time to appendicectomy of 29 days [IQR 2-124]. Elective appendicectomy accounted for 17% (31/180) of operations with normal histology found in 39% (12/31). The overall normal histology rate was 11% (19/167). There were 7/167 malignancies and 3/167 neuroendocrine tumours identified at delayed operation. The presence of a faecolith (HR 1.72; 95% CI 1.18–2.51) and CRP>300 versus <50 (HR 3.05; 95% CI 1.6–5.81) were independent risk factors for failure of antibiotic-management (n=441). Conclusion The success rate of non-operative appendicitis management was 71% at one-year. Appendicitis recurrence was associated with the presence of a faecolith, malignancy and significantly raised CRP. These factors should be considered when counselling patients on non-operative management.