Endoscopic retrograde appendicitis therapy plus antibiotics versus antibiotics alone for uncomplicated acute appendicitis with appendicolith: a propensity score-matched cohort

Background: Appendicolith is an independent risk factor for treatment failure with antibiotics alone in nonoperative management (NOM) of uncomplicated acute appendicitis (UAA). Endoscopic retrograde appendicitis therapy (ERAT) can relieve appendicolith-induced luminal obstruction, representing a promising NOM for this high-risk subgroup. This study evaluated the efficacy and safety of ERAT plus antibiotics in treating UAA with appendicolith. Methods: This multicenter retrospective cohort study included 11 tertiary hospitals across 4 Chinese provinces. From August 2021 to July 2023, UAA patients with imaging-confirmed appendicoliths receiving ERAT plus antibiotics or antibiotics alone as initial NOM were screened. After exclusion and propensity score matching (1:1), 139 well-balanced pairs were collected. The primary outcome was initial treatment success (successful completion of initial treatment, discharge without alternative treatment). Secondary outcomes included length of initial hospital stay, appendicitis recurrence within 1-year follow-up, recurrence time, and incidence of overall adverse events. Results: ERAT plus antibiotics achieved a significantly higher initial treatment success rate (95.7% vs. 78.4%; P<0.001) and lower 1-year recurrence rate (14.3% vs. 43.1%; P<0.001) than antibiotics alone. The ERAT plus antibiotics group had a longer median (interquartile range) recurrence time (279 [155, 328] vs. 32 [22, 88] days; P<0.001) and shorter median initial hospital stay (3 [3, 5] vs. 4 [3, 5] days; P<0.001). Adverse event rates were low and comparable (2.2% vs. 4.3%; P = 0.50). Conclusion: Findings support ERAT plus antibiotics as the preferred initial NOM strategy in UAA patients with appendicoliths compared with antibiotics alone.