Antibiotic resistance and genotypic characterization by PFGE of clinical and environmental isolates of enterococci

Fifty-four Enterococcus faecalis and 20 Enterococcus faecium isolates from clinical and non-human sources in Rome, Italy, were characterized by antibi otic resistance and pulsed field gel electrophoresis (PFGE). Resistance to vancomycin, teicoplanin, ampicillin, and ciprofloxacin was more frequent in E faecium than in E. faecalis, whereas high-level resistance to aminoglyco side was found primarily in E. faecalis. Multi-resistance was found primari ly among clinical isolates, but was also observed among environmental isola tes. Common genotypes shared among clinical and environmental isolates were observed, however, the majority of isolates occurred as unique, source-spe cific clones. Several PFGE types were associated with shared features in th eir antibiotic resistance patterns; evidences of clonal spread between and within wards were also noted. This is the first report indicating clonal re latedness between human and environmental enterococci isolated in Italy. (C ) 2001 Published by Elsevier Science BN. on behalf of the Federation of Eur opean Microbiological Societies.