title: [A multicentre study on the pathogenic agents in 665 adult patients with community-acquired pneumonia in cities of China].
abstract: OBJECTIVE
  To investigate the pathogenic causes of community-acquired pneumonia (CAP) in adult patients in China, the relation of previous antibiotic use and the Pneumonia Patient Outcome Research Team (PORT) classification to microbial etiology, and the prevalence of drug resistance of common CAP bacteria.
  
  
  METHODS
  A prospective study was performed on 665 consecutive adult patients with CAP at 12 centers in 7 Chinese cities during one year. The etiology of pneumonia was considered if one of the following criteria was met: (1) valid sputum sample yielding one or more predominant strains; (2) blood cultures yielding a bacterial pathogen; (3) seroconversion, a > or = 4-fold increase or decrease titers of antibodies to Mycoplasma pneumoniae, Chlamydia pneumoniae and Legionella pneumophila. Minimum inhibitory concentration (MIC) of respiratory tract isolates was determined using the agar dilution method.
  
  
  RESULTS
  Pathogens were identified in 324/610 patients (53.1%) with valid serum samples and sputum cultures as follows: Mycoplasma pneumoniae (126, 20.7%), Streptococcus pneumoniae (63, 10.3%), Haemophilus influenzae (56, 9.2%), Chlamydia pneumoniae (40, 6.6%), Klebsiella pneumoniae (37, 6.1%), Legionella pneumophila (31, 5.1%), Staphylococcus aureus (23, 3.8%), Escherichia coli (10, 1.6%), Moraxella catarrhalis (8, 1.3%), Pseudomonas aeruginosa (6, 1.0%). Of 195 patients with a bacterial pathogen, an atypical pathogen was identified in 62 (10.2%) cases. The non-susceptibility rate of Streptococcus pneumoniae to penicillin, azithromycin, and moxifloxacin was 20.3%, 75.4% and 4.3% respectively.
  
  
  CONCLUSIONS
  Atypical pathogens have important role in CAP, with Mycoplasma pneumoniae being the most common pathogen, and mixed infection of atypical pathogens with bacteria was found in 10.2% of the cases. Streptococcus pneumoniae and Haemophilus influenzae remain the most important bacteria for CAP. More than 75.0% of Streptococcus pneumoniae was resistant to macrolides and 20.3% was resistant to penicillin.
authors.affiliation: Department of Respiratory Medicine, General Hospital of PLA, Beijing 100853, China.
authors.forename: You-ning
authors.initials: YN
authors.lastname: Liu
authors.forename: Min-jun
authors.initials: MJ
authors.lastname: Chen
authors.forename: Tie-mei
authors.initials: TM
authors.lastname: Zhao
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.forename: Qing-feng
authors.initials: QF
authors.lastname: Liu
authors.forename: Bai-qiang
authors.initials: BQ
authors.lastname: Cai
authors.forename: Bin
authors.initials: B
authors.lastname: Cao
authors.forename: Tie-ying
authors.initials: TY
authors.lastname: Sun
authors.forename: Yun-jian
authors.initials: YJ
authors.lastname: Hu
authors.forename: Qing-yu
authors.initials: QY
authors.lastname: Xiu
authors.forename: Xin
authors.initials: X
authors.lastname: Zhou
authors.forename: Xing
authors.initials: X
authors.lastname: Ding
authors.forename: Lan
authors.initials: L
authors.lastname: Yang
authors.forename: Jian-sheng
authors.initials: JS
authors.lastname: Zhuo
authors.forename: Ying-chun
authors.initials: YC
authors.lastname: Tang
authors.forename: Kou-xing
authors.initials: KX
authors.lastname: Zhang
authors.forename: De-rong
authors.initials: DR
authors.lastname: Liang
authors.forename: Xiao-ju
authors.initials: XJ
authors.lastname: Lü
authors.forename: Sheng-qi
authors.initials: SQ
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Yun-song
authors.initials: YS
authors.lastname: Yu
authors.forename: Ze-qing
authors.initials: ZQ
authors.lastname: Wei
authors.forename: Ke-jing
authors.initials: KJ
authors.lastname: Ying
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
authors.forename: Ping
authors.initials: P
authors.lastname: Chen
authors.forename: Xiao-na
authors.initials: XN
authors.lastname: Hou
mesh_terms: D000328:Adult; D000368:Aged; D002681:China / Q000453:epidemiology; D016993:Chlamydophila pneumoniae / Q000302:isolation & purification; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D005260:Female; D006193:Haemophilus influenzae / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D009177:Mycoplasma pneumoniae / Q000302:isolation & purification; D011014:Pneumonia / Q000453:epidemiology* / Q000382:microbiology*; D011446:Prospective Studies; D013296:Streptococcus pneumoniae / Q000302:isolation & purification; D014505:Urban Population