Evidence-based optimisation of empirical antibiotic regimens in paediatric complicated appendicitis: a retrospective study of 94 patients

Abstract

BACKGROUND: Acute appendicitis is the most frequent surgical emergency in the paediatric population. Complicated appendicitis accounts for 30% of cases and is inextricably linked to postoperative infectious complications. A study at our institution showed that amoxicillin-clavulanate resistant Escherichia coli in complicated appendicitis was significantly linked to postoperative infectious complications. These findings led to a change in the empirical antibiotic protocol (amoxicillin-clavulanate changed to ceftriaxone + metronidazole as of 2017), intending to reduce postoperative infectious complications in complicated appendicitis in our institution. AIM OF THE STUDY: This study aimed to analyse the microbiology and resistance profiles of pathogens of complicated appendicitis at our institution since implementing the new antibiotic protocol and the postoperative infectious complications rate. METHODS: We designed a retrospective comparative cohort study. During the defined study period (01 January 2017 to 31 July 2020), medical records were analysed for cases of acute appendicitis, complicated appendicitis and postoperative infectious complications, retaining only those who fulfilled inclusion criteria. Postoperative outcomes, microbiology and antibiotic resistance of peritoneal swabs were analysed. RESULTS: During the study period, 95 patients presented with a complicated appendicitis, and 11 (12%) developed postoperative infectious complications. The most frequent pathogens found in complicated appendicitis were E. coli (66%), Streptococcus anginosus (45%), and Bacteroides fragilis (22%). Pseudomonas aeruginosa was present in 17% of complicated appendicitis. Pathogens involved in postoperative infectious complications mirrored the distribution found in complicated appendicitis without postoperative infectious complications. Antibiotic susceptibility analysis showed that 10 (15%) of E. coli strains were resistant to amoxicillin-clavulanate but sensitive to ceftriaxone + metronidazole, with only one strain responsible for causing a postoperative infectious complication. Six additional strains of E. coli (9%) were resistant to amoxicillin-clavulanate and our empirical antibiotic regimen but were not associated with an increase in postoperative infectious complications. Compared with our previous study, there was a decrease in postoperative infectious complications from 16% to 12%. Postoperative infectious complications caused by amoxicillin-clavulanate-resistant E. coli decreased from 28% to 9%. CONCLUSION: This retrospective study demonstrated a decrease in the rate of postoperative infectious complications due to amoxicillin-clavulanate-resistant E. coli in complicated appendicitis. These findings accentuate the need to implement evidence-based treatment protocols based on local microbiology profiles and resistance rates to optimise post-operative antibiotics in complicated appendicitis.

Effects of evidence‐based nursing on surgical site wound infection in patients undergoing acute appendicitis surgery: A meta‐analysis

“…The present study used a meta‐analysis to evaluate the effectiveness of EBN in reducing postoperative wound infections in AA, and the results showed that the rate of wound infections in patients with AA who underwent EBN (OR = 0.23, 95% CI: 0.14–0.38, p < 0.001) was significantly lower than in those under conventional care. This is consistent with the findings of Gerber et al, who found that the implementation of EBN interventions resulted in a decrease in the incidence of postoperative wound infections caused by amoxicillin/clavulanic acid Escherichia coli , optimising treatment outcomes 51 . This result therefore suggests that the EBN intervention is superior to conventional care interventions and is safe and feasible.…”

“…This is consistent with the findings of Gerber et al, who found that the implementation of EBN interventions resulted in a decrease in the incidence of postoperative wound infections caused by amoxicillin/clavulanic acid Escherichia coli , optimising treatment outcomes. 51 This result therefore suggests that the EBN intervention is superior to conventional care interventions and is safe and feasible.…”

Intraoperative bacterial cultures fail to reliably predict the bacterial spectrum encountered during infectious complications after appendicitis

“…Antimicrobial stewardship has only begun to intervene in the field of intra-abdominal infections [ 20 ]. While most studies focus on the reduction of antibiotic use, there are also studies highlighting the benefit of intraoperative cultures and a strict postoperative antibiotic regimen introduced following local microbiological findings of the recent past in order to lower SSI [ 21 , 22 ]. The general advice to de-escalate antibiotics after resistance testing is done is rarely followed for abdominal infections.…”