Colonization of Residents and Staff of an Italian Long-Term Care Facility and an Adjacent Acute Care Hospital Geriatrics Unit by Multidrug-Resistant Bacteria

Microb Drug Resist. 2023 Oct;29(10):477-484. doi: 10.1089/mdr.2023.0019. Epub 2023 Jun 30.

Abstract

In 2022, we undertook a point prevalence screening study for Enterobacterales with extended-spectrum β-lactamases (ESBLs), high-level AmpC cephalosporinases and carbapenemases, and also methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) in a long-term care facility (LTCF) and the associated acute-care hospital Geriatrics unit in Bolzano, Northern Italy. Urine samples and rectal, inguinal, oropharyngeal, and nasal swabs were plated on selective agar plates. Metadata of the patients, including demographic data, were collected, and risk factors for colonization were determined. ESBL, AmpC, carbapenemase, and quinolone resistance genes were investigated by the HybriSpot 12 PCR AUTO System. The following colonization percentages by multidrug-resistant (MDR) bacteria have been found in LTCF residents: all MDR organisms, 59.5%; ESBL producers, 46.0% (mainly CTX-M-type enzymes); carbapenemase producers, 1.1% (one Klebsiella pneumoniae with KPC-type); MRSA, 4.5%; VRE, 6.7%. Colonization by MDR bacteria was 18.9% for LTCF staff and 45.0% for Geriatrics unit patients. Peripheral vascular disease, the presence of any medical device, cancer, and a Katz Index of 0 were significant risk factors for colonization of LTCF residents by MDR bacteria in univariate and/or multivariate regression analysis. To conclude, the ongoing widespread diffusion of MDR bacteria in the LTCF suggests that efforts should be strengthened on MDR screening, implementation of infection control strategies, and antibiotic stewardship programs targeting the unique aspects of LTCFs. ClinicalTrials.gov ID: 0530250-BZ Reg01 30/08/2022.

Keywords: AmpC; ESBLs; Enterobacterales; MRSA; VRE; carbapenemases; long-term care facility.