Multiple preoperative biomarkers are associated with incidence of surgical site infection following surgeries of ankle fractures.

The aim of the study was to investigate the epidemiologic characteristics of surgical site infection (SSI) following surgeries of ankle fractures. This was a retrospective study. Patients who underwent surgeries for ankle fractures in our hospital between January 2016 and June 2019 were included. Inpatient medical records were inquired for data collection, including demographics, comorbidities, injury-related data, laboratory biomarkers, and confirmation of the SSI cases. Univariate analyses and multivariate logistic regression analyses were used to identify the independent risk factors. Among the 1532 patients, 45 had a postoperative SSI, indicating the incidence rate of 2.9%. About 18% of SSIs were identified after discharge. Twenty percent of SSIs were caused by mixed bacteria, and 39% were caused by drug-resistant bacteria. In the final multivariate model, 7 factors including 5 biomarkers were identified to be independently associated with SSI: gender (male vs female, OR, 2.69; 95% CI, 1.33-4.76), perioperative blood transfusion (OR. 3.02; 95% CI, 1.30-7.04), albumin <35 g/L (OR, 2.87; 95% CI, 1.31-6.31), lower high-density lipoprotein cholesterol (HDL-C) (OR, 2.34; 95% CI, 1.19-4.60), haemoglobin (OR, 2.16; 95% CI, 1.03-4.67), elevated alanine aminotransferase (OR, 2.09; 95% CI, 1.10-3.95) and neutrophile/lymphocyte rate (NLR, OR, 3.45; 95% CI, 1.33-6.74). These epidemiologic data on SSI may help counsel patients about the risk of SSI, individualised assessment of the risk factors, and accordingly the risk stratification.