Risk factors for Carbapenem-resistant Enterobacterales infections: A case-control study

Over years, concerning Carbapenem-resistant Enterobacterales (CRE) have advanced globally, posing a major threat to global health. Prior studies highlight previous antibiotic use and prolonged hospital stays as paramount risk factors for CRE infections. However, there are limited reports available with a focus on identifying risk factors for CRE infections by comparing CRE cases with controls. The aim is to evaluate factors associated with CRE infections among individuals admitted to hospitals in Mthatha.

A retrospective case-control study among patients who attended Nelson Mandela Academic Hospital (NMAH) and Mthatha Regional Hospital (MRH), Eastern Cape, South Africa. Demographic, medical history and current hospitalisation factors were captured on clinical research forms. GraphPad Prism version 8 software was used for statistical analysis.

Out of the 226 participants with CRE infection, CRE cases were more likely than controls to be adults (51.9%, odds ratio [OR]: 1.34, 95% confidence interval [CI]: 0.72-2.55) and of male sex (54.9%, OR: 1.48, 95% CI: 0,87-2,45). Significant risk factors for CRE infections included underlying illnesses (OR: 2.55, 95% CI: 1.41-4.60, p = 0.002), urine catheterisation (OR: 5.40, 95% CI: 1.45-18.33, p = 0.01), intravascular devices (OR: 2.48, 95% CI: 1.06-6.03, p = 0.05) and prolonged hospital stay (OR: 1.87, 95% CI: 1.01-3.39, p = 0.048). CRE cases compared to controls were almost twice as likely to demise or have an extended hospital stay of more than one month. Klebsiella pneumoniae (62.6%) and Enterobacter cloacae (60.6%) were prevalent Enterobacterales associated with CRE.

Significant risk factors for CRE infections are underlying illnesses, urine catheterisation, intravascular devices and prolonged hospitalisation.Contribution: The complicated nature of CRE infections highlights the importance of targeted interventions to mitigate their spread and impact on public health.