Epidemiological data on the acquisition of carbapenem-resistant Enterobacterales through weekly rectal swabs in non-critically ill patients undergoing antimicrobial therapy: a short-term surveillance study.

Objective: To evaluate the connection between non-critically ill hospitalized patients and the acquisition of carbapenem-resistant Enterobacterales (CRE).

Design: An observational prospective cohort study from January 2018 to December 2019.

Setting: A single tertiary referral center.

Participants: Non-critically ill subjects admitted to general medical wards who received antimicrobial therapy <48 h.

Methods: Rectal swab cultures at admission and weekly for CRE surveillance. CRE isolates were confirmed using carbapenem disk diffusion susceptibility and genotypic carbapenemase testing. Clinical characteristics and outcomes were also evaluated.

Results: Of 110 subjects, 66.4% were women, the mean age was 67 years, and 336 bacterial isolates were detected from rectal swab cultures. 55 (16.4%) isolates from 25 subjects exhibited phenotypic resistance to carbapenem. Klebsiella pneumoniae (50.9%) and Escherichia coli (30.9%) were common CRE, harboring New Delhi metallo-beta-lactamase (NDM) (50.9%), oxacillinase-48 (OXA-48) (12.7%), and co-NDM/OXA-48 (20.0%). Subjects with acquired CRE had higher APACHE II scores (P = 0.030), received piperacillin-tazobactam (P = 0.004), underwent prolonged antimicrobial therapy (P = 0.009), and experienced longer hospital stays (P = 0.001) compared to CRE-negative subjects. None of the CRE-positive subjects developed an acquired infection.

Conclusions: Acquired CRE colonization is prevalent among non-critically ill patients. Factors such as disease severity, the type and duration of antimicrobial therapy, and the length of hospital stays may increase the risk of CRE acquisition in non-critically ill populations.