Enterobacter cloacae prevalence in fracture-related infections of the lower leg: a 7-year single centre retrospective cohort study

Introduction Fracture-related infection (FRI) is a complication of trauma surgery. While FRI treatment guidelines are based on prosthetic joint infection data, we hypothesized that the presence of Gram-negative bacteria like Enterobacter cloacae might be underestimated in FRI. Our primary aim was to identify the prevalence of pathogens in FRI of the lower leg. A second aim was to explore factors associated with the presence of Enterobacter cloacae.Methodology Patients with an FRI of the lower leg between 1 January 2016 and 31 December 2022 were included. We performed a descriptive statistical analysis, and a multivariable logistic regression to examine associations between the outcome (presence/absence of Enterobacter cloacae) and selected covariates.Results A total of 81 patients were included. The most frequent pathogens were Enterobacter cloacae (n = 42, 52%) and Staphylococcus aureus (n = 18, 22%). Enterobacter cloacae were the most cultured bacteria in monobacterial (n = 23/51, 45%) and polybacterial infections (n = 19/30, 63%). Fractures treated without external fixators (OR = 0.13, 95% CI [0.03–0.45], p < 0.001) and patients with higher BMI (OR = 0.86, 95% CI [0.76–0.96], p = 0.012) were significantly associated with a reduced odds of having an Enterobacter infection, while controlling for age, sex and open versus closed fracture.Conclusion A high prevalence of Enterobacter cloacae was observed in culture-positive FRI of the lower leg. Patients without external fixators and with higher BMI showed reduced odds of having an Enterobacter infection. This elevated prevalence emphasizes that this pathogen may warrant broader clinical attention. Our findings highlight the need for large prospective multicentric studies.