Multidrug-Resistant Bacteria Independently Predict Postoperative Infection Risks in Acute Appendicitis

In patients undergoing laparoscopic appendectomy for acute appendicitis, the presence of multidrug-resistant bacterial infections independently predicts postoperative infectious complications and higher healthcare resource utilization. According to findings from a retrospective cohort study of 500 patients, multidrug-resistant status significantly elevated the likelihood of adverse postoperative events, indicating that the clinical impact of resistant pathogens extends beyond baseline disease severity.

The study was prompted by the increasing prevalence of multidrug-resistant bacteria in intra-abdominal infections, which has generated ongoing concern regarding optimal perioperative management and surgical outcomes. Investigators set out to determine whether multidrug-resistant status serves as an independent predictor of postoperative infectious complications and healthcare resource utilization after systematically adjusting for potential confounding clinical factors.

Conducted as a single-center retrospective cohort investigation, the research evaluated 500 patients treated with laparoscopic appendectomy for acute appendicitis between January 2020 and December 2024. All enrolled patients received empirical third-generation cephalosporin therapy both preoperatively and perioperatively, and intraoperative bacterial cultures alongside antimicrobial susceptibility testing were systematically performed to establish microbial profiles.

Multidrug resistance was formally defined as nonsusceptibility to at least one agent in three or more antimicrobial categories. The primary clinical endpoint evaluated was postoperative infectious complications, encompassing surgical site infection and intra-abdominal abscess, while secondary endpoints comprised antibiotic escalation, postoperative antibiotic duration, length of postoperative hospital stay, and 30-day hospital readmission.

Unadjusted comparisons demonstrated that patients with multidrug-resistant infections experienced significantly longer postoperative hospitalizations and antibiotic courses, as well as higher rates of surgical site infections, intra-abdominal abscesses, overall postoperative infectious complications, antibiotic escalation, and 30-day readmissions (all P < 0.05). In multivariate logistic regression analysis, multidrug resistance remained an independent predictor of overall infectious complications (adjusted odds ratio = 6.51; 95% confidence interval: 2.51–16.90; P < 0.001) and was strongly associated with antibiotic escalation (adjusted odds ratio = 11.59; 95% confidence interval: 5.11–26.28; P < 0.001).

Multivariate linear regression further confirmed that multidrug-resistant positivity independently correlated with prolonged antibiotic therapy (beta = 1.37; 95% confidence interval: 1.01–1.74; P < 0.001) and prolonged postoperative hospital stay (beta = 1.39; 95% confidence interval: 0.98–1.79; P < 0.001). The researchers concluded that pathogen identification and multidrug resistance are critical considerations for individualized antimicrobial management, supporting the future evaluation of risk stratification models and pathogen-directed antimicrobial strategies in acute appendicitis.

The increasing prevalence of multidrug-resistant bacteria in intra-abdominal infections has raised clinical concerns regarding perioperative management and postoperative outcomes. In response to these concerns, the researchers designed the study to evaluate whether multidrug-resistant status independently predicts postoperative infectious complications and healthcare resource utilization in patients undergoing laparoscopic appendectomy after adjusting for potential confounding factors.

The single-center investigation evaluated 500 patients who underwent laparoscopic appendectomy for acute appendicitis between January 2020 and December 2024. All 500 enrolled patients received empirical third-generation cephalosporin therapy both preoperatively and perioperatively. During surgical intervention, intraoperative bacterial cultures with antimicrobial susceptibility testing were performed for all patients. Multidrug resistance was formally defined by the investigators as nonsusceptibility to at least one agent in three or more antimicrobial categories, establishing the precise microbiological criteria used to distinguish multidrug-resistant positive infections from multidrug-resistant negative cases.

The primary clinical endpoint specified in the study was postoperative infectious complications, which included surgical site infection and intra-abdominal abscess. Secondary outcomes evaluated by the team included antibiotic escalation, length of hospital stay, postoperative antibiotic duration, and 30-day readmission. To determine independent relationships while controlling for confounding variables, the researchers employed two distinct multivariable modeling approaches: multivariate logistic regression was used to identify independent predictors of infectious complications and antibiotic escalation, while multivariate linear regression was used to analyze factors influencing hospital stay length and postoperative antibiotic duration.

In baseline comparisons, patients with multidrug-resistant positive infections experienced significantly longer postoperative hospital stays and longer postoperative antibiotic durations than multidrug-resistant negative patients. Patients with resistant infections also had significantly higher rates of surgical site infection, intra-abdominal abscess, overall postoperative infectious complications, antibiotic escalation, and 30-day readmission (all P < 0.05). Multivariate logistic regression confirmed that multidrug-resistant positivity was independently associated with postoperative infectious complications (adjusted odds ratio = 6.51; 95% confidence interval: 2.51–16.90; P < 0.001), indicating that its effect extends beyond baseline disease severity. Furthermore, multidrug-resistant status was an independent predictor of antibiotic escalation (adjusted odds ratio = 11.59; 95% confidence interval: 5.11–26.28; P < 0.001).

After adjusting for confounders in the multivariate linear regression models, multidrug-resistant positivity remained significantly associated with prolonged antibiotic therapy (beta = 1.37; 95% confidence interval: 1.01–1.74; P < 0.001) and prolonged postoperative hospital stay (beta = 1.39; 95% confidence interval: 0.98–1.79; P < 0.001). The authors concluded that multidrug-resistant positive culture is independently associated with postoperative infectious complications and antibiotic escalation in acute appendicitis, while also driving greater healthcare resource utilization. These findings suggest that multidrug-resistant status and pathogen identification are relevant considerations for individualized antimicrobial management, providing an evidence base for further evaluation of multidrug-resistant risk stratification and pathogen-directed antimicrobial strategies.

Subject of Research: Postoperative outcomes of multidrug-resistant infections in acute appendicitis

Article Title: Independent impact of multidrug-resistant organisms on postoperative outcomes in acute appendicitis patients: a retrospective cohort study

Article References: Li, J., Yuan, F., Shi, M., Yang, Z., & Wu, Z. (2026). Independent impact of multidrug-resistant organisms on postoperative outcomes in acute appendicitis patients: a retrospective cohort study. BMC Surgery. https://doi.org/10.1186/s12893-026-04262-8

Image Credits: AI Generated

DOI: 10.1186/s12893-026-04262-8

Keywords: acute appendicitis, laparoscopic appendectomy, multidrug-resistant organisms, intra-abdominal infections, surgical site infection, intra-abdominal abscess, postoperative complications, antimicrobial susceptibility testing, bacterial cultures, third-generation cephalosporins, antibiotic escalation, length of hospital stay, postoperative antibiotic duration, 30-day readmission, multivariate logistic regression, pathogen-directed antimicrobial therapy