title: Molecular epidemiology and clinical characteristics of drug-resistant Mycobacterium tuberculosis in a tuberculosis referral hospital in China.
abstract: BACKGROUND
  Despite the large number of drug-resistant tuberculosis (TB) cases in China, few studies have comprehensively analyzed the drug resistance-associated gene mutations and genotypes in relation to the clinical characteristics of M. tuberculosis (Mtb) isolates.
  
  
  RESULTS
  We thus analyzed the phenotypic and genotypic drug resistance profiles of 115 Mtb clinical isolates recovered from a tuberculosis referral hospital in Beijing, China. We also performed genotyping by 28 loci MIRU-VNTR analysis. Socio-demographic and clinical data were retrieved from medical records and analyzed. In total, 78 types of mutations (including 42 previously reported and 36 newly identified ones) were identified in 115 Mtb clinical isolates. There was significant correlation between phenotypic and genotypic drug resistance rates for first-line anti-TB drugs (P<0.001). Genotyping revealed 101 MIRU-VNTR types, with 20 isolates (17.4%) being clustered and 95 isolates (82.6%) having unique genotypes. Higher proportion of re-treatment cases was observed among patients with clustered isolates than those with unique MIRU-VNTR genotypes (75.0% vs. 41.1%). Moreover, clinical epidemiological links were identified among patients infected by Mtb strains belonging to the same clusters, suggesting a potential of transmission among patients.
  
  
  CONCLUSIONS
  Our study provided information on novel potential drug resistance-associated mutations in Mtb. In addition, the genotyping data from our study suggested that enforcement of the implementation of genotyping in diagnostic routines would provide important information for better monitor and control of TB transmission.
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Hong Kong Special Administrative Region, China.
authors.forename: Susanna K P
authors.initials: SK
authors.lastname: Lau
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.affiliation: National Center for Tuberculosis Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Institute for Tuberculosis Research, the 309 Hospital, Beijing, China.
authors.forename: Hong Min
authors.initials: HM
authors.lastname: Li
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Bing Xi
authors.initials: BX
authors.lastname: Li
authors.affiliation: Institute for Tuberculosis Research, the 309 Hospital, Beijing, China.
authors.forename: Yong Liang
authors.initials: YL
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Hong Kong Special Administrative Region, China.
authors.forename: Patrick C Y
authors.initials: PC
authors.lastname: Woo
authors.affiliation: CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Cui Hua
authors.initials: CH
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000995:Antitubercular Agents / Q000494:pharmacology; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D018598:Minisatellite Repeats; D058885:Multilocus Sequence Typing; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D011159:Population Surveillance; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012017:Referral and Consultation; D018088:Tuberculosis, Multidrug-Resistant / Q000453:epidemiology* / Q000382:microbiology*; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents; D012336:RNA, Ribosomal, 16S