Distribution of pathogenic bacteria and analysis of risk factors for surgical site infections after hepatobiliary surgery

BACKGROUND: Surgical site infections (SSIs) are major complications following hepatobiliary surgery, leading to prolonged hospitalization, increased healthcare costs, and higher morbidity. Identifying causative pathogens and clinical risk factors is essential for guiding effective prevention and management strategies. METHODS: This retrospective study included 916 adult patients who underwent hepatobiliary surgery between January 2023 and June 2024. Patients were classified into SSI (n = 51) and non-SSI (n = 865) groups according to Centers for Disease Control and Prevention (CDC) diagnostic criteria. Clinical, surgical, and microbiological data were collected. Pathogen identification and antimicrobial susceptibility testing were conducted using standard microbiological techniques and Clinical and Laboratory Standards Institute (CLSI) guidelines. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors for SSI occurrence. Model calibration and discrimination were assessed with the Hosmer–Lemeshow test and area under the receiver operating characteristic curve (AUC). RESULTS: Among 916 patients, 51 (5.6%) developed SSIs. Gram-negative bacilli predominated (66.7%), with Escherichia coli (29.4%) and Klebsiella pneumoniae (21.6%) as the most frequent pathogens. Extended-spectrum β-lactamase production was identified in 20.0% of E. coli and 18.1% of K. pneumoniae isolates, whereas carbapenem resistance was low. Multivariate analysis identified diabetes mellitus (odds ratio (Moraes CMT, Corrêa LM, Procópio RJ, Carmo G, Navarro TP. Rev Col Bras Cir 49:e20223125.1, 2022) 2.08, 95% confidence interval [CI] 1.07–4.05), hypoalbuminemia < 35 g/L (OR 2.95, 95% CI 1.60–5.45), operative duration ≥ 240 min (OR 2.72, 95% CI 1.45–5.11), and biliary drainage (OR 1.91, 95% CI 1.01–3.61) as independent predictors. Model calibration was adequate (Hosmer–Lemeshow p = 0.62), with good discrimination (AUC = 0.81). CONCLUSIONS: SSIs following hepatobiliary surgery are primarily caused by multidrug-resistant Gram-negative organisms. Perioperative optimization, including glycemic and nutritional management, reduction of operative time, and careful use of biliary drainage, is critical for lowering. CLINICAL TRIAL NUMBER: Not applicable.