Extended-Spectrum Beta-Lactamase- And Carbapenemase-Producing Enterobacterales Intestinal Carriage Among Outpatients: Microbiological And Epidemiological Differences Between Private Dwelling Residents And Nursing Home Residents

The aim of this work was to assess the prevalence of carbapenemase-producing and extended-spectrum beta-lactamase-producing Enterobacterales (ESBLPE) intestinal carriage among private dwelling residents (PDR) and nursing home residents (NHR) from the catchment area of Hospital Verge de la Cinta (Tortosa. North-Eastern Spain), and to depict clinicoepidemiological features of colonized individuals. Prevalence of ESBLPE carriage amid 762 PDR (0-94 years) who had feces collected for routine culture was 7.3% and 31% among 71 NHR (68-98 years) screened upon hospital admission. The mean age of colonized and noncolonized subjects was 30 and 32.8 years in PDR (p = 0.58) and 85 and 87 years in NHR (p = 0.32). The predominant ESBLPE was CTX-M-15-producingEscherichia coli(42.8% in PDR and 68.2% in NHR [25% and 86.7% belonging to O25b-ST131 clone;p < 0.0001]), followed by CTX-M-9-group- and SHV-producingE. coliand by CTX-M-15-producingKlebsiella pneumoniae.Overall, 72.7% of ESBLPE were multidrug resistant and 46.2% carried transferable quinolone determinants. Institutionalization in a nursing home was a risk factor for ESBLPE and extended-spectrum beta-lactamase (ESBL)-producing O25b-ST131E. colicarriage in individuals over 67 years (odds ratio 7.7 and 14.1). Previous antibiotic use and skin ulcers were significantly associated with ESBLPE carriage in NHR. Age E. colicolonization. Only two PDR, with known risk factors, bore OXA-48-producing isolates. These results highlight the role of nonhospitalized intestinal carriers, particularly NHR, as ESBLPE reservoirs and the preponderance of CTX-M-15, mainly linked to O25b-ST131 clone, as well as the emergence of carbapenemase-producing Enterobacterales carriers.