Antibiotic resistance of Enterobacteriaceae causing urinary tract infections in elderly patients living in the community and in the nursing home: A retrospective observational study

Objectives: Although nursing homes are thought to be significant reservoirs of antibiotic-resistant bacteria, very few large population-based studies comparing antibiotic resistance prevalence in nursing homes and in the community have adjusted for patient characteristics. Our objective was to compare the prevalence of antibiotic resistance of Enterobacteriaceae cultured from urine samples of nursing home residents with that of community-dwelling adults, all aged 65 years or older. Methods: This study analysed around 20 000 positive urine samples sent to a large laboratory in north-eastern France from 2014 to 2017, collected from individuals aged 65 years or older. A multivariable logistic regression model adjusted for patient characteristics (gender, age, year of sampling, presence of urinary catheter and number of urine samples/year) compared the resistance of Escherichia coli, Proteus mirabilis and Klebsiella pneumoniae to amoxicillin/clavulanate, nitrofurantoin, trimethoprim/sulfamethoxazole, nalidixic acid, ofloxacin, ciprofloxacin and ceftriaxone, as well as their possible EBSL production, in nursing home residents and community-dwellers. Results: Nursing home residents had a higher adjusted OR (aOR) of Enterobacteriaceae (E. coli, P. mirabilis or K. pneumoniae) resistant to amoxicillin/clavulanate (aOR 1.38, 95% CI 1.27-1.50), ciprofloxacin (aOR 1.33, 95% CI 1.20-1.49) and ceftriaxone (aOR 1.37, 95% CI 1.15-1.63) or producing an ESBL (aOR 1.43, 95% CI 1.18-1.72), but did not differ in resistance to nitrofurantoin or trimethoprim/sulfamethoxazole. Conclusions: Elderly people in nursing homes had a risk around 40% higher than their community-dwelling peers of having antibiotic-resistant Enterobacteriaceae cultured fromtheir urine samples. Antibiotic stewardship and infection prevention and control programmes should be implemented in nursing homes.