title: Prevalence of Chlamydia pneumoniae in the atherosclerotic plaque of patients with unstable angina and its relation with serology.
abstract: BACKGROUND
  Chlamydia pneumoniae has been associated with coronary artery disease by both seroepidemiological studies, and by direct detection of the micro-organism in atherosclerotic lesions. This bacteria could play a potential role in the development of acute coronary events. We examined coronary arteries from patients with unstable angina in order to verify an endovascular presence of C. pneumoniae, and to determine if there is any relationship between serology of acute infection by this pathogen and its presence inside the atherosclerotic plaque of these patients.
  
  
  METHODS
  We analysed a total of 76 atherosclerotic plaques obtained from 45 patients who underwent coronary artery bypass surgery. In all patients unstable angina was present within the prior 3 weeks. The presence of C. pneumoniae in the plaque was determined by nested polymerase chain reaction (PCR). Antichlamydial immunoglobulin G (IgG), A (IgA) and M (IgM) was examined by microimmunofluorescence and compared to the PCR result.
  
  
  RESULTS
  DNA of C. pneumoniae was detected in 57 (75%) of 76 atherosclerotic lesions. In most cases (74/76: 97%) a positive IgA, IgM or IgG result was seen. Seven (12%) and 54 (94%) of the 57 PCR positive plaques came from patients with a positive IgM and IgA result, respectively. There was no statistical significant difference between PCR positive and PCR negative plaques in patients with a positive or negative serological result. Clinical characteristics were similarly distributed in patients with and without infected lesions.
  
  
  CONCLUSIONS
  C. pneumoniae organisms are frequently found in the atherosclerotic lesions of patients undergoing coronary surgery for unstable angina. Neither serological results of acute or recent infection by C. pneumoniae nor clinical characteristics are useful in predicting the individual risk of harbouring C. pneumoniae in the coronary lesions of patients with unstable angina.
authors.affiliation: Servicio de Cardiologia, Hospital Clinico San Carlos, Plaza Cristo Rey, 28040, Madrid, Spain. jzamorano@hcsc.insalud.es <jzamorano@hcsc.insalud.es>
authors.forename: José
authors.initials: J
authors.lastname: Zamorano
authors.forename: Avelina
authors.initials: A
authors.lastname: Suarez
authors.forename: Julio
authors.initials: J
authors.lastname: Garcia Tejada
authors.forename: Ester
authors.initials: E
authors.lastname: Culebras
authors.forename: Jose
authors.initials: J
authors.lastname: Castañón
authors.forename: Juan
authors.initials: J
authors.lastname: Picazo
authors.forename: Raúl
authors.initials: R
authors.lastname: Moreno
authors.forename: Luis
authors.initials: L
authors.lastname: Sanchez-Harguindey
mesh_terms: D000328:Adult; D000368:Aged; D000789:Angina, Unstable / Q000276:immunology* / Q000382:microbiology* / Q000473:pathology; D002690:Chlamydia Infections / Q000150:complications / Q000453:epidemiology* / Q000276:immunology / Q000473:pathology; D016993:Chlamydophila pneumoniae / Q000302:isolation & purification*; D001026:Coronary Artery Bypass; D003324:Coronary Artery Disease / Q000150:complications / Q000382:microbiology* / Q000473:pathology*; D003331:Coronary Vessels / Q000382:microbiology* / Q000473:pathology; D005260:Female; D006801:Humans; D007136:Immunoglobulins / Q000097:blood; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods; D015995:Prevalence; D011446:Prospective Studies; D016036:Seroepidemiologic Studies; D012698:Serologic Tests
chemical_list: D007136:Immunoglobulins