title: Clonal spread of CC17 vancomycin-resistant Enterococcus faecium with multilocus sequence type 78 (ST78) and a novel ST444 in Taiwan.
abstract: From May 2007 to January 2008, 30 isolates of vancomycin-resistant enterococci (VRE), including 29 Enterococcus faecium (96.7%) and 1 E. faecalis (3.3%) were obtained from various clinical specimens of 30 patients treated at a university hospital in Taiwan. Among these patients, 27 had VRE infections, including urinary tract infection (n = 16), bacteremia (n = 5), wound infection (n = 5), and central nervous system infection (n = 1). Three patients had VRE colonization. All of these isolates belonged to the vanA genotype with vancomycin minimum inhibitory concentrations of 64>or=128 microg/ml. The isolate of E. faecalis had VanB phenotype-vanA genotype. All these isolates were susceptible to linezolid and were inhibited by tigecycline at 0.25 microg/ml. Multilocus sequence typing (MLST) analysis of the E. faecium isolates showed that 82.8% were ST78, which belongs to lineage C1. Transposon typing classified the 30 isolates of VRE into three types and most of the Tn1546-like elements contained an IS1251-like insertion sequence. Mating experiments showed that the vanA gene clusters were transferable at a frequency of about 10(-6) to 10(-7). Our findings indicate that nosocomial spread of VRE resulted from dissemination of lineage C1 E. faecium clones, including a novel E. faecium MLST type (ST444), and the horizontal transfer of Tn1546 elements among enterococci.
authors.affiliation: Division of Pediatric Infectious Diseases, Department of Pediatrics, Chang Gung Children's Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Y-C
authors.initials: YC
authors.lastname: Hsieh
authors.forename: W-S
authors.initials: WS
authors.lastname: Lee
authors.forename: T-Y
authors.initials: TY
authors.lastname: Ou
authors.forename: P-R
authors.initials: PR
authors.lastname: Hsueh
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques; D019729:Carbon-Oxygen Ligases / Q000235:genetics; D016000:Cluster Analysis; D003227:Conjugation, Genetic; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology / Q000473:pathology; D016172:DNA Fingerprinting; D004251:DNA Transposable Elements; D016984:Enterococcus faecium / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D022761:Gene Transfer, Horizontal; D005838:Genotype; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology* / Q000473:pathology; D006785:Hospitals, University; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D017422:Sequence Analysis, DNA; D013624:Taiwan / Q000453:epidemiology; D020713:Vancomycin Resistance
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004251:DNA Transposable Elements; C071437:VanA ligase, Bacteria; D019729:Carbon-Oxygen Ligases