CO15 | A single-center experience in screening patients for carbapenem-resistant enterobacteriaceae at admission

Background and Aims: Bloodstream infections due to carbapenem-resistant enterobacteriaceae (CRE) is a leading cause of morbidity and mortality. Our aim was to investigate the prevalence of colonization from CRE among patients admitted to Internal Medicine Unit.Materials and Methods: We retrospectively collected rectal swab specimens from patients at admission between November and December 2023. Laboratory searched for gram negative resistance markers analysing rectal samples with multiplex PCR-based BD MAX assay to detect the 5 major carbapenemase families (OXA-48, VIM/IMP, KPC, NDM).Results: 184 rectal samples were collected. The overall carriage rate of CRE was 6% (KPC and NDM in 73% and 27% patients, respectively). Seventy-two patients with positive rectal swabs showed almost one of the following features: hospitalization/antibiotics in the last month, haemodialysis. In our cohort positivity rate of urine and blood cultures was 5% and 16% respectively. No correlation between CRE colonization and urine positivity was found; 18% patients showed both blood cultures and rectal swab positive and died. Mortality rate in patients with positive blood cultures and negative rectal swab was 33%.Conclusions: the number of positive rectal swabs compared to the total number of hospitalized patients remained low thanks to the procedures adopted after identification of carriers. Colonization increases the risk of infection by multidrug-resistant bacteria, having a remarkable impact on prognosis (as we observed mortality up to 100% in patient with blood culture and rectal swab positive).