Carbapenem-resistant Enterobacteriaceae among kidney transplant recipients – insights on the risk of acquisition and CRE infection

Background Kidney transplant recipients are a risk group for carbapenem-resistant Enterobacteriaceae infection.Objectives This study aimed to identify risk factors for CRE acquisition and infection among kidney transplant recipients.Methods We conducted a case-control study; we defined the case as kidney transplant recipient with positive culture for carbapenem-resistant Enterobacteriaceae identified between January 2010 and February 2019. Controls were chosen among kidney transplant recipients hospitalized in the same period of cases (1:2). Surveillance culture for carbapenem-resistant Enterobacteriaceae was performed at admission and weekly during hospital stay. The risk factors analysis for carbapenem-resistant Enterobacteriaceae infection was performed among patients colonized by these bacteria.Results We identified 331 patients colonized with carbapenem-resistant Enterobacteriaceae; The median time from transplantation to first carbapenem-resistant Enterobacteriaceae positive culture was 42 days (range from 3 to 7399 days); 125(37.8%) patients developed infection; the most common site was urinary tract. Risk factors for carbapenem-resistant Enterobacteriaceae acquisition were recipient age >45-year, diabetes nephropathy, donor age >55-year, ureteral stent at kidney transplantation, delay of graft function, median lymphocytes count <800cells/mm3, and acute cellular rejection. Risk factors for carbapenem-resistant Enterobacteriaceae infection were recipient age at CRE acquisition >50-year; median lymphocytes count ≤700 cells/mm3, carbapenem use, and colonization by polymyxin-resistant strain. Patients colonized by polymyxin and carbapenem resistant Enterobacteriaceae strain who used carbapenem had a 93.8% probability of developing infection by this agent.Conclusion Carbapenem-resistant Enterobacteriaceae acquisition after kidney transplant is related to graft conditions, immunosuppression degree. Among carbapenem-resistant Enterobacteriaceae colonized patients, special attention is needed for those harbouring polymyxin-resistant strains.