title: [Antimicrobial susceptibility of community-acquired respiratory tract pathogens isolated from adults in China during 2009 and 2010].
abstract: OBJECTIVE
  To investigate the drug-resistance rates of community-acquired respiratory tract pathogens isolated from adults in China during 2009 and 2010.
  
  
  METHODS
  A total of 1793 strains (S. aureus 421, S. pneumoniae 420, K. pneumoniae 404, H. influenzae 313, other Streptococcus. spp 149, and M. catarrhalis 86) of non-duplicated community-acquired respiratory tract pathogens were isolated from 11 hospitals in 6 cities. The MIC values were determined by the broth microdilution method, and the production of β-lactamase was tested using a nitrocefin-based test.
  
  
  RESULTS
  All of the S.aureus isolates were methicillin-sensitive (MSSA). Of the MSSA isolates, less than 1% (4/421) was resistant to β-lactamase inhibitor combinations, about 13.1% (55/421) and 9% (38/421) resistant to levofloxacin and moxifloxacin, and 57% (240/421), 53.2% (224/421), and 88.7% (373/421) resistant to azithromycin, clarithromycin, and penicillin, respectively. No S. aureus isolates resistant to vancomycin were detected in this study. Based on different criteria, the percentages of penicillin-sensitive S. pneumoniae (PSSP), penicillin-intermediate S. pneumoniae (PISP), and penicillin-resistant S. pneumoniae (PRSP) were 24.4% (102/420), 27.3% (115/420), 48.3% (203/420) (Oral) and 1.9% (8/420), 9% (38/420), 89.1% (374/420) (parenteral), respectively. The resistance rates of S. pneumonia to azithromycin, clarithromycin, cefaclor, cefuroxime, ceftriaxone and amoxicillin with clavulanic acid were 88.2% (370/420), 87.4% (367/420), 45.3% (190/420), 41.9% (176/420), 10.2% (43/420), and 5.2% (22/420), respectively. About 2.6% (11/420) and 0.2% (1/420) of S. pneumonia isolates were resistant to levofloxacin and moxifloxacin. More than 70% (104/149) of β-hemolytic streptococci isolates were resistant to azithromycin and clarithromycin, and about 10.1% (15/149) of isolates were resistant to levofloxacin. The resistance rates of K.pneumonia to most antibiotics were > 20% (81/404), and that of ceftazidime was lower than cefuroxime, cefaclor, and ceftriaxone. The mean prevalence value of ESBL producing K. pneumonia was 38.8% (157/404), with significantly regional variations. More than 90% of H. influenza and M. catarrhalis were susceptible to most antibiotics, with resistance rate of < 5% (16/313, H. influenza; 4/86, M. catarrhalis). The mean productions of β-lactamase in H. influenza and M. catarrhalis were 13.1% (41/313) and 91.7% (79/86), respectively.
  
  
  CONCLUSIONS
  The percentage of PRSP increased significantly, and the resistance rates of community-acquired respiratory tract pathogens to common antibiotics such as macrolide and cephalosporins increased gradually. New fluoroquinolones such as moxifloxacin showed a high antimicrobial activity against most of the respiratory pathogens.
authors.affiliation: Department of Clinical Laboratory, Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Ya-li
authors.initials: YL
authors.lastname: Liu
authors.forename: Min-jun
authors.initials: MJ
authors.lastname: Chen
authors.forename: Ying-chun
authors.initials: YC
authors.lastname: Xu
authors.forename: Hong-li
authors.initials: HL
authors.lastname: Sun
authors.forename: Qi-wen
authors.initials: QW
authors.lastname: Yang
authors.forename: Yun-jian
authors.initials: YJ
authors.lastname: Hu
authors.forename: Bin
authors.initials: B
authors.lastname: Cao
authors.forename: Yun-zhuo
authors.initials: YZ
authors.lastname: Chu
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Rong
authors.initials: R
authors.lastname: Zhang
authors.forename: Yun-song
authors.initials: YS
authors.lastname: Yu
authors.forename: Zi-Yong
authors.initials: ZY
authors.lastname: Sun
authors.forename: Chao
authors.initials: C
authors.lastname: Zhuo
authors.forename: Yu-xing
authors.initials: YX
authors.lastname: Ni
authors.forename: Bi-jie
authors.initials: BJ
authors.lastname: Hu
mesh_terms: D000328:Adult; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001424:Bacterial Infections / Q000188:drug therapy / Q000382:microbiology* / Q000517:prevention & control; D002681:China; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000382:microbiology* / Q000517:prevention & control; D024881:Drug Resistance, Bacterial; D006193:Haemophilus influenzae / Q000187:drug effects / Q000302:isolation & purification; D006801:Humans; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D001936:Moraxella catarrhalis / Q000187:drug effects / Q000302:isolation & purification; D012141:Respiratory Tract Infections / Q000188:drug therapy / Q000382:microbiology* / Q000517:prevention & control; D013211:Staphylococcus aureus / Q000187:drug effects / Q000302:isolation & purification; D013296:Streptococcus pneumoniae / Q000187:drug effects / Q000302:isolation & purification; D014505:Urban Population
chemical_list: D000890:Anti-Infective Agents