Bacterial Pathogens and Antibiotic Resistance Patterns in Pediatric Appendicitis: Implications for Antibiotic Choice

Acute appendicitis is the most common cause for an acute abdomen worldwide, and laparoscopic appendectomy is the treatment of choice in most regions. Perioperative antibiotic therapy has shown to reduce postoperative complications. Conservative treatment strategies are under evaluation, especially in pediatric cohorts, but are not yet routinely used. Many prior studies have evaluated pathogens and resistance patterns involved in acute appendicitis, finding large differences in geographical distribution and recommended antibiotic agents. This study analyzes the local resistance patterns for acute appendicitis at a single referral center in Germany to optimize antibiotic therapy.

A retrospective cohort analysis was performed of 181 histologically confirmed pediatric patients with appendicitis. Items analyzed were symptoms, laboratory, imaging, microbiologic results and management strategies.

One hundred thirty-nine microbiologic samples were obtained intraoperatively, rendering 226 isolates of 36 different microbiologic species. The most common pathogens were Escherichia coli (31%), members of the Streptococcus anginosus group (21%), Bacteroides fragilis (15%) and Pseudomonas aeruginosa (9%). Pseudomonas and S. anginosus group were significantly associated with perforation. Resistance rates were high for ampicillin/sulbactam (31%), cefuroxime/ceftriaxone (37%) and ciprofloxacin (51%), mostly due to intrinsic resistance. Resistance to cefuroxime/metronidazole (17%), piperacillin/tazobactam (8%) and meropenem (3%) was low. Perforation, fever and higher C-reactive protein values were linked to resistance against cefuroxime/metronidazole.

In our cohort, cefuroxime/metronidazole seems to be an adequate option for uncomplicated and piperacillin/tazobactam for complicated cases.