title: High Prevalence of Hypervirulent Klebsiella pneumoniae Infection in China: Geographic Distribution, Clinical Characteristics, and Antimicrobial Resistance.
abstract: Hypervirulent Klebsiella pneumoniae (hvKP) is traditionally defined by hypermucoviscosity, but data based on genetic background are limited. Antimicrobial-resistant hvKP has been increasingly reported but has not yet been systematically studied. K. pneumoniae isolates from bloodstream infections, hospital-acquired pneumonia, and intra-abdominal infections were collected from 10 cities in China during February to July 2013. Clinical data were collected from medical records. All K. pneumoniae isolates were investigated by antimicrobial susceptibility testing, string test, extended-spectrum β-lactamase (ESBL) gene detection, capsular serotypes, virulence gene profiles, and multilocus sequence typing. hvKP was defined by aerobactin detection. Of 230 K. pneumoniae isolates, 37.8% were hvKP. The prevalence of hvKP varied among different cities, with the highest rate in Wuhan (73.9%) and the lowest in Zhejiang (8.3%). Hypermucoviscosity and the presence of K1, K2, K20, and rmpA genes were strongly associated with hvKP (P < 0.001). A significantly higher incidence of liver abscess (P = 0.026), sepsis (P = 0.038), and invasive infections (P = 0.043) was caused by hvKP. Cancer (odds ratio [OR], 2.285) and diabetes mellitus (OR, 2.256) appeared to be independent variables associated with hvKP infections by multivariate analysis. Importantly, 12.6% of hvKP isolates produced ESBLs, and most of them carried blaCTX-M genes. Patients with neutropenia (37.5% versus 5.6%; P = 0.020), history of systemic steroid therapy (37.5% versus 5.6%; P = 0.020), and combination therapy (62.5% versus 16.7%; P = 0.009) were more likely to be infected with ESBL-producing hvKP. The prevalence of hvKP is high in China and has a varied geographic distribution. ESBL-producing hvKP is emerging, suggesting an urgent need to enhance clinical awareness, especially for immunocompromised patients receiving combination therapy.
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China.
authors.forename: Yawei
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China.
authors.forename: Chunjiang
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China.
authors.forename: Hongbin
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China.
authors.forename: Henan
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China.
authors.forename: Feifei
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China.
authors.forename: Shuguang
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China.
authors.forename: Ruobing
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Clinical Laboratory, Peking University People's Hospital, Beijing, China whuibj@163.com.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D016470:Bacteremia / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002681:China / Q000453:epidemiology; D003428:Cross Infection / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D048909:Diabetes Complications; D003920:Diabetes Mellitus / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D005260:Female; D015870:Gene Expression; D006801:Humans; D059413:Intraabdominal Infections / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D007710:Klebsiella Infections / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D007711:Klebsiella pneumoniae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D008297:Male; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D009369:Neoplasms / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D010802:Phylogeny; D058974:Phylogeography; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism; D018410:Pneumonia, Bacterial / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology; D015995:Prevalence; D011446:Prospective Studies; D065288:Serogroup; D014774:Virulence; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; C512267:RmpA protein, Klebsiella pneumoniae; D001618:beta-Lactamases