Research Summary

Antibiotics for Appendicitis: 10-Year APPAC Results

Edited by:
Anthony Calabro, MA

Key Highlights

  • At 10 years, the appendicitis recurrence rate after antibiotic therapy was 37.8%.
  • The cumulative appendectomy rate among patients initially treated with antibiotics reached 44.3%.
  • The complication rate was significantly lower in the antibiotic group compared with the appendectomy group (P < .001).
  • There was no significant difference in quality of life between patients treated with antibiotics and those undergoing appendectomy.

Antibiotic therapy remains a viable long-term option for adults with uncomplicated acute appendicitis, according to new 10-year follow-up data from the Appendicitis Acuta (APPAC) randomized clinical trial published in JAMA. Investigators reported that although recurrence and subsequent appendectomy were common, overall outcomes supported antibiotics as an alternative to surgery in appropriately selected patients.

The findings provide one of the longest follow-up periods to date for nonoperative management of appendicitis, addressing a key evidence gap regarding durability of antibiotic treatment beyond 5 years.

The APPAC trial was a multicenter randomized clinical trial conducted at 6 Finnish hospitals between November 2009 and June 2012. A total of 530 adults aged 18 to 60 years with computed tomography–confirmed uncomplicated acute appendicitis were randomized to either open appendectomy (n = 273) or antibiotic therapy (n = 257). The antibiotic regimen consisted of 3 days of intravenous ertapenem followed by 7 days of oral levofloxacin and metronidazole.

This analysis represents a 10-year observational follow-up of patients initially assigned to antibiotics, with outcomes assessed through April 29, 2024. The primary endpoints included appendicitis recurrence and cumulative appendectomy rates, along with complications, quality of life, and additional post hoc assessments such as tumor detection.

Study Findings

At 10-year follow-up, 253 of 257 patients (98.4%) in the antibiotic group were evaluated. The true appendicitis recurrence rate, confirmed by histopathology, was 37.8% (95% CI, 31.6%-44.1%), corresponding to 87 of 230 patients. The cumulative appendectomy rate reached 44.3% (95% CI, 38.2%-50.4%), representing 112 of 253 patients over the study period.

Complication rates differed significantly between treatment groups. The cumulative complication rate was 27.4% (95% CI, 21.6%-33.3%) in the appendectomy group compared with 8.5% (95% CI, 4.8%-12.1%) in the antibiotic group (P < .001). Quality-of-life outcomes were similar between groups, with no statistically significant difference observed (median health index value, 1.0 for both groups; P = .18).

Clinical Implications

According to the study authors, the long-term recurrence and appendectomy rates observed after initial antibiotic treatment support the use of antibiotics as an option for uncomplicated acute appendicitis in adult patients. The findings indicate that although a proportion of patients will require subsequent surgery, many can avoid appendectomy over a prolonged follow-up period.

Expert Commentary

“Among patients initially treated with antibiotics for uncomplicated acute appendicitis, the rate of recurrence and appendectomy at 10-year follow-up supports the use of antibiotics as an option for uncomplicated acute appendicitis in adult patients,” the researchers concluded.

Reference
Salminen P, Salminen R, Kallio J, et al. Antibiotic therapy for uncomplicated acute appendicitis: ten-year follow-up of the APPAC randomized clinical trial. JAMA. 2026;335(12):1041-1049. doi:10.1001/jama.2025.25921