Narrow- versus Broad-Spectrum Antibiotics for Simple Acute Appendicitis Treated by Appendectomy: A Post Hoc Analysis of EAST MUSTANG Study

Abstract

BackgroundWe sought to compare the effectiveness of narrow- versus broad-spectrum antibiotics (abx) in preventing infectious complications in adults with acute appendicitis treated with appendectomy. MethodsIn this post hoc analysis of a prospective multicenter observational study of appendicitis in adults (≥18 y) conducted from January 2017 to June 2018, we included only patients with simple appendicitis. Subjects were grouped based on receipt of broad-spectrum or narrow-spectrum abx before and/or after appendectomy. Outcomes compared were surgical site infection, intra-abdominal abscess, secondary interventions (percutaneous drainage or operation), emergency department (ED) visits, 30-d readmission, and hospital length of stay. ResultsA total of 2336 subjects were analyzed. In comparing narrow (n = 778) versus broad (n = 1558) groups, there were no differences in male sex (53% versus 54%, P = 0.704), white blood cell (13.0 ± 3.9 versus 13.4 ± 4.5, P = 0.05), Alvarado score (6 [5-7] versus 6 [5-7], P = 0.25), or Charlson comorbidity index (0 [0-1] versus 0 [0-1], P = 0.09). A total of 688 (29%) received postoperative abx, [184 (24%) narrow and 504 (32%) broad, P < 0.001] for a median 5 [2-7] d [42 (23%) narrow and 235 (47%) broad, P < 0.001]. There were no significant differences between narrow and broad groups in surgical site infection, intra-abdominal abscess, secondary interventions, ED visits, or hospital readmissions. ConclusionsSignificant practice variation in duration and spectrum of antibiotic adjunct for surgical treatment of simple acute appendicitis treatment is evident, and broad-spectrum abx did not offer clinical advantages over narrow-spectrum abx. Restriction of antibiotic spectrum should be considered, although randomized trials are required to overcome selection bias.