quinupristin-dalfopristin and Poultry-Diseases

Fifty-four quinupristin/dalfopristin-resistant Enterococcus faecium (QDREF) isolated from chickens and pigs during 2002-2003 in Korea were screened by PCR for the presence of streptogramin resistance genes vatD, vatE, and vgbA, and macrolide resistance gene ermB. None of the QDREF isolates carried vgbA and vatD genes, while vatE and ermB were detected in 9.2% and 74% of the isolates, respectively. Twenty-six percent (14/54) of the QDREF isolates contained none of the resistance determinants tested. Pulsed-field gel electrophoresis (PFGE) patterns revealed high heterogeneity: 47 different patterns for 54 QDREF evaluated. Identical PFGE types were observed in two pairs of chicken isolates and a pair of pig isolates, respectively, but chicken isolates did not share PFGE pattern with pig isolates, suggesting clonal spread of QDREF strain between the same species of animals but not between different species of animals. This is the first report, to our knowledge, of vatE-positive E. faecium isolates and also the first evidence of clonal spread of QDREF strain between animals in Korea.

Topics: Animals; Anti-Bacterial Agents; Chickens; Drug Resistance, Multiple, Bacterial; Enterococcus faecium; Gram-Positive Bacterial Infections; Korea; Poultry Diseases; Streptogramins; Swine; Swine Diseases; Virginiamycin

Topics: Animals; Anti-Bacterial Agents; Drug Resistance, Multiple, Bacterial; Enterococcus faecium; Gram-Positive Bacterial Infections; Humans; Poultry Diseases; Swine Diseases; Virginiamycin

In this study, quinupristin/dalfopristin (Q/D)-resistant Enterococcus faecium isolates (33 from poultry farms and 1 from a human outpatient) with Q/D minimal inhibitory concentrations ranging from 4 microg/mL to 32 microg/mL were analysed. Polymerase chain reaction detected the presence of vat(E) in all isolates. Using pulsed-field gel electrophoresis (PFGE), 14 distinct PFGE patterns were identified. The human E. faecium isolate was distinguishable from the 33 farm isolates by PFGE. Southern hybridisation localised the vat(E) gene to an 11 kb plasmid and resulted in five plasmid hybridisation types. The vat(E)-carrying plasmid from the human isolate showed a nearly identical hybridisation pattern to a plasmid from a farm isolate. This study showed that the vat(E) gene, conferring resistance to Q/D, was carried on different plasmids in a heterogeneous group of E. faecium, some of which may be acquired by E. faecium capable of infecting humans.

Topics: Acetyltransferases; Animals; Anti-Bacterial Agents; Bacterial Proteins; Blotting, Southern; Chickens; Electrophoresis, Gel, Pulsed-Field; Enterococcus faecium; Gram-Positive Bacterial Infections; Humans; Microbial Sensitivity Tests; Plasmids; Polymerase Chain Reaction; Poultry Diseases; Turkeys; Virginiamycin