title: [Correlation between Chlamydia pneumoniae infection and chronic obstructive pulmonary disease].
abstract: OBJECTIVE
  To investigate the correlation between Chlamydia pneumonia (Cpn) infection and chronic obstructive pulmonary disease (COPD).
  
  
  METHODS
  82 patients with acute exacerbation COPD (AE-COPD) or stabilized COPD patients at outpatient visits, in the People's Hospital of Jiangyin city from Aug. 2010 to May 2012, together with 46 cases having stationary phase COPD and 38 healthy volunteers as control group, were involved in this study. Patients were bled 2 ml, on the next day of hospitalization while patients at emergency room were bled 2 ml immediately, but bled again on the 15(th) day. Serum was separated through cryopreservation and the Cpn antibodies (IgG, IgM and IgA antibodies) were detected, under micro-immunofluorescence.
  
  
  RESULTS
  In terms of IgG in the three groups, the positive rates did not show significant differences (P > 0.05) but the GMT of the IgG in the AE-COPD group was significantly higher (P < 0.01) than that in the control group. IgA positive rate among the three groups; AE-COPD appeared the highest. There was no significant difference between the AE-COPD group and stationary phase COPD group (P > 0.05), however, there were significant differences between the AE-COPD group, the stationary phase COPD group and the control group (P < 0.01). In terms of GMT of IgA in the three groups, there was significant difference between the AE-COPD group and stationary phase COPD group (P > 0.05), but with significant difference between the AE-COPD group and the control group (P > 0.01). There was significant difference between stationary phase COPD group and the control group (P > 0.05). When comparing both the rates of acute infection and chronic infection on the AE-COPD groups with the control group, there appeared significant differences (P < 0.05, P < 0.01). When comparing the acute and chronic infection between the stationary phase COPD group and the control group, the rate of acute infection did not show significant difference (P > 0.05) while the chronic infection rate appear to have had significant difference (P < 0.01).
  
  
  CONCLUSIONS
  Cpn infection seemed to be closely related to the development of COPD.
authors.affiliation: Department of Respiratory Medicine of People's Hospital of Jiangyin, Jiangyin 214400, China. tangliangfa20@163.com
authors.forename: Liang-Fa
authors.initials: LF
authors.lastname: Tang
authors.forename: Dan-Feng
authors.initials: DF
authors.lastname: Wang
authors.forename: Li-Qiang
authors.initials: LQ
authors.lastname: Cao
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Wu
authors.forename: Jian
authors.initials: J
authors.lastname: Lü
authors.forename: Fang-Fang
authors.initials: FF
authors.lastname: Yu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000097:blood; D016022:Case-Control Studies; D002690:Chlamydia Infections / Q000453:epidemiology*; D016993:Chlamydophila pneumoniae; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology* / Q000382:microbiology*
chemical_list: D000907:Antibodies, Bacterial