Original Research Article|Articles in Press

Factors associated with recurrent appendicitis after nonoperative management


      • 29% of patients had recurrent appendicitis within 6 months.
      • Median time to recurrent appendicitis was 17 days.
      • A competing-risk analysis was used to find predictors of recurrent appendicitis.
      • Appendicolith was the only factor associated with recurrent appendicitis.
      • By 6 months, 67% of patients with an appendicolith had undergone appendectomy.



      The objective of this study is to identify predictors for recurrent appendicitis in patients with appendicitis previously treated nonoperatively.


      This is a prospective cohort study of all adult patients with appendicitis treated at a tertiary care hospital. Patient demographics, radiographic information, management, and clinical outcomes were recorded. The primary outcome was recurrent appendicitis within 6 months after discharge from the index admission. Given the competing risk of interval appendectomy, a time-to-event competing-risk analysis was performed.


      Of the 699 patients presenting with appendicitis, 74 were treated nonoperatively (35 [47%] were women; median [IQR] age, 48 [33,64] years), and 21 patients (29%) had recurrent appendicitis. On univariate and multivariate analysis, presence of an appendicolith on imaging was the only factor associated with a higher risk of recurrent appendicitis (p = 0.02).


      The presence of appendicolith was associated with an increased risk of developing recurrent appendicitis within 6 months.

      Graphical abstract


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