Dramatic Increase in Prevalence of Fecal Carriage of Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae during Nonoutbreak Situations in Spain

摘要: The occurrence of extended-spectrum β-lactamase (ESBL)-producing isolates has increased worldwide. Fecal carriage ESBL-producing mainly been detected in nosocomial outbreaks, and few studies have evaluated fecal during nonoutbreak situations among patients the community. We studied prevalence ESBLs 1,239 samples from 849 (64.1% whom were ambulatory) 1991 compared data with those obtained 2003 for 400 386 (75.9% 108 independent healthy volunteers. Samples diluted saline cultured two MacConkey agar plates supplemented ceftazidime (1 μg/ml) cefotaxime μg/ml), respectively. Colonies screened (by double-disk synergy test) ESBL production. clonal relatedness all was determined by pulsed-field gel electrophoresis XbaI digestion; characterized isoelectric focusing, PCR, sequencing. rates significantly (P < 0.001) both hospitalized outpatients, 0.3 0.7%, respectively, 1991, to 11.8 5.5%, 2003. rate volunteers 3.7%. All recovered nonepidemic clones Escherichia coli. characterization revealed an increasing diversity types: TEM-4 CTX-M-10 only enzymes whereas TEM-4, TEM-52, SHV-12, CTX-M-9, CTX-M-10, CTX-M-14, a CTX-M-2-like enzyme outpatients corresponded CTX-M-9-type cluster (62.5%) SHV-12 (31.2%), patients. frequencies coresistance as follows: sulfonamide, 75%; tetracycline, 64.3%; streptomycin, 57.1%; quinolones, 53.5%; trimethoprim, 50%. establishment these community non-β-lactam antibiotics, including represent opportunity become endemic.