Extended-spectrum beta-lactamase-producing Enterobacteriacae: unexpected low prevalence of carriage in elderly French residents

SIR—Extended-spectrum β-lactamases (ESBLs) are the major cause of resistance to cephalosporins. Since 2000, CTX-M enzymes have become the most prevalent, particularly in Escherichia coli [1, 2]. CTX-M-15-producing E. coli of the ST131 lineage has become endemic worldwide [3, 4]. The epidemiology of ESBL-producing Enterobacteriaceae (ESBLE) is complex, involving spread in the community, nosocomial acquisition and plasmid transfer between Enterobacteriaceae. It has been suggested that nursing homes (NHs) and long-term care facilities (LTCFs) may be significant to the epidemiology of ESBLE [5–8]. Elderly patients cumulate risk factors for carriage of multidrug-resistant (MDR) bacteria and residents have been recently shown to be reservoirs of ESBLE [9, 10]. A group of experts appointed by the French Ministry of Health to establish suggestions to tackle ESBLE recently recommended monitoring the prevalence of ESBLE carriage in elderly patients by rectal or urinary screening [11]. To increase our knowledge concerning the epidemiology of ESBLE carriage and associated risk factors in elderly French residents of care facilities, we conducted a multicentre point-prevalence study. In particular, we evaluated colonisation of residents at 40 institutions in two distant French regions.