title: Dissemination of a clone carrying a fosA3-harbouring plasmid mediates high fosfomycin resistance rate of KPC-producing Klebsiella pneumoniae in China.
abstract: Fosfomycin has been proposed as an adjunct to other active agents for treating KPC-producing Klebsiella pneumoniae infections. This study aimed to investigate the prevalence of fosfomycin resistance and plasmid-mediated resistance determinants among KPC-producing K. pneumoniae isolates from clinical samples in China. In total, 278 KPC-producing and 80 extended-spectrum β-lactamase (ESBL)-producing (non-KPC-producing) clinical K. pneumoniae isolates were collected in 12 hospitals from 2010 to 2013. Fosfomycin susceptibility testing was carried out using the agar dilution method. Phylogenetic clonal patterns were revealed by pulsed-field gel electrophoresis (PFGE). Isolates were screened for plasmid-mediated fosfomycin resistance genes (fosA, fosA3 and fosC2) by PCR amplification. A plasmid was completely sequenced by next-generation sequencing. The fosfomycin resistance rate in KPC-producers (60.8%; 169/278) was significantly higher than in ESBL-producers (12.5%; 10/80). In addition, 94 KPC-producing isolates were positive for fosA3 and most of them were clonally related. A 23939-bp plasmid (pFOS18) co-harbouring fosA3 and bla(KPC-2) was completely sequenced, revealing that the fosA3 gene was flanked by two copies of IS26; however, bla(KPC-2) was located on a Tn3-Tn4401 integration structure. Although the fosA3 and blaKPC-2 genes are located on different transposon systems, they are able to spread together worldwide through plasmid transfer. Dissemination of the clone carrying the fosA3-harbouring plasmid mediates the high fosfomycin resistance rate of KPC-producing K. pneumoniae in China. Fosfomycin as an alternative option for treating infections caused by KPC-producing K. pneumoniae should not be recommended in hospitals in which fosfomycin-resistant clonal dissemination is emerging.
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Shen
authors.affiliation: State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China.
authors.forename: Zeqing
authors.initials: Z
authors.lastname: Wei
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China.
authors.forename: Lilin
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China.
authors.forename: Fang
authors.initials: F
authors.lastname: He
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China.
authors.forename: Keren
authors.initials: K
authors.lastname: Shi
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China.
authors.forename: Yanfei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China.
authors.forename: Haiping
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China. Electronic address: yvys119@163.com.
authors.forename: Yunsong
authors.initials: Y
authors.lastname: Yu
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002681:China / Q000453:epidemiology; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005578:Fosfomycin / Q000494:pharmacology*; D005838:Genotype; D006761:Hospitals; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010957:Plasmids; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D005578:Fosfomycin; D001618:beta-Lactamases
keywords: Clonal dissemination; Fosfomycin resistance; KPC-producing Klebsiella pneumoniae; Plasmid-mediated resistance determinant