title: The prevalence of carbapenemase genes and plasmid-mediated quinolone resistance determinants in carbapenem-resistant Enterobacteriaceae from five teaching hospitals in central China.
abstract: We investigated the prevalence of β-lactamase genes and plasmid-mediated quinolone resistance (PMQR) determinants in 51 carbapenem-resistant Enterobacteriaceae (CRE) from five teaching hospitals in central China. The prevalence of carbapenem resistance in Enterobacteriaceae was 1·0% (51/5012). Of 51 CRE, 31 (60·8%) isolates were positive for one tested carbapenemase gene, while 10 (19·6%) were simultaneously positive for two tested carbapenemase genes. The positive rates of bla KPC-2, bla NDM-1, bla IMP-4, bla IMP-26 and bla IMP-8 were 54·9%, 17·6%, 11·8%, 11·8% and 3·9%, respectively. Of 10 CRE with two carbapenemase genes, three, five, one and one were positive for bla KPC-2 and bla IMP-4, bla KPC-2 and bla IMP-26, bla KPC-2 and bla IMP-8, and bla KPC-2 and bla NDM-1, respectively. Eight of nine bla NDM-1-positive isolates lacked carbapenemases by the modified Hodge test, while 27/28 isolates harbouring bla KPC-2 were positive for carbapenemases determined by this test; 41·2% of the CRE-positive isolates also harboured ESBL genes in various combinations (three and two positive for bla KPC-2 also carried bla DHA-1 and bla CMY-2). The positive rates of qnrS1, qnrA1, qnrB and aac-(6/)-Ib-cr in CRE were 25·5%, 9·8%, 23·5% and 15·7%, respectively. In particular, 7/9 isolates harbouring bla NDM-1 were positive for these quinolone resistance genes, of which five carried qnrS1 and two carried qnrS1 and qnrB4. All but two of 29 Klebsiella pneumoniae isolates were grouped into 20 clonal clusters by PFGE, with the predominant cluster accounting for four bla KPC-2-positive isolates distributed in the same hospital. We conclude that there is a high prevalence of bla NDM-1 and PMQR determinants in CRE isolates in central China. Multiple resistance determinants in various combinations co-exist in these strains and we report for the first time the co-existence of bla KPC-2 and bla IMP-26 in a strain of Klebsiella oxytoca.
authors.affiliation: Department of Laboratory Medicine,Second Affiliated Hospital of Nanchang University,Nanchang,China.
authors.forename: L
authors.initials: L
authors.lastname: Hu
authors.affiliation: Department of Laboratory Medicine,Second Affiliated Hospital of Nanchang University,Nanchang,China.
authors.forename: Q
authors.initials: Q
authors.lastname: Zhong
authors.affiliation: Department of Laboratory Medicine,First Affiliated Hospital of Wenzhou Medical College,Wenzhou,China.
authors.forename: Y
authors.initials: Y
authors.lastname: Shang
authors.affiliation: Department of Laboratory Medicine,Second Affiliated Hospital of Nanchang University,Nanchang,China.
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Laboratory Medicine,Second Affiliated Hospital of Nanchang University,Nanchang,China.
authors.forename: C
authors.initials: C
authors.lastname: Ning
authors.affiliation: Department of Respiratory Medicine,First Affiliated Hospital of Wenzhou Medical College,Wenzhou,China.
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Laboratory Medicine,Second Affiliated Hospital of Nanchang University,Nanchang,China.
authors.forename: Y
authors.initials: Y
authors.lastname: Hang
authors.affiliation: Department of Laboratory Medicine,Second Affiliated Hospital of Nanchang University,Nanchang,China.
authors.forename: J
authors.initials: J
authors.lastname: Xiong
authors.affiliation: Department of Laboratory Medicine,Second Affiliated Hospital of Nanchang University,Nanchang,China.
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Respiratory Medicine,First Affiliated Hospital of Wenzhou Medical College,Wenzhou,China.
authors.forename: Y
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Departments of Medicine and Microbiology,Louisiana State University Health Sciences Center,New Orleans, LA,USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Qin
authors.affiliation: Departments of Medicine and Microbiology,Louisiana State University Health Sciences Center,New Orleans, LA,USA.
authors.forename: C
authors.initials: C
authors.lastname: Parsons
authors.affiliation: Department of Respiratory Medicine,First Affiliated Hospital of Wenzhou Medical College,Wenzhou,China.
authors.forename: L
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Laboratory Medicine,First Affiliated Hospital of Wenzhou Medical College,Wenzhou,China.
authors.forename: F
authors.initials: F
authors.lastname: Yu
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002681:China / Q000453:epidemiology; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000201:enzymology*; D004756:Enterobacteriaceae Infections / Q000235:genetics / Q000382:microbiology; D006784:Hospitals, Teaching; D006801:Humans; D010957:Plasmids / Q000235:genetics / Q000378:metabolism*; D015363:Quinolones / Q000494:pharmacology*; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015363:Quinolones; D001618:beta-Lactamases; C063912:carbapenemase