title: Effect of azithromycin treatment on endothelial function in patients with coronary artery disease and evidence of Chlamydia pneumoniae infection.
abstract: BACKGROUND
  It has been suggested that infection with Chlamydia pneumoniae(CPn) can trigger inflammatory mechanisms that may in turn impair vascular endothelial function. The aim of the present study was to assess whether treatment with the macrolide antibiotic azithromycin improves endothelial function in patients with coronary artery disease and antibodies positive to CPn.
  
  
  RESULTS
  We carried out a randomized, prospective, double-blind, placebo-controlled trial in 40 male patients (mean age, 55+/-9 years) with documented coronary artery disease and positive CPn-IgG antibody titers. After baseline evaluation, patients were randomized to receive either azithromycin or placebo for 5 weeks. Flow-mediated dilation (FMD) of the brachial artery and E-selectin, von Willebrand factor, and C-reactive protein (CRP) levels were assessed at study entry and at the end of the treatment period. Our results showed that patients who received azithromycin had a significant improvement in FMD (mean change, 2.1+/-1.1%; P<0.005). In contrast, FMD was not significantly changed in the placebo group (mean change, -0.02+/-0.2%, P=0.64). Azithromycin therapy also resulted in a significant decrease of E-selectin and von Willebrand factor levels. CRP levels were not significantly altered by treatment with either azithromycin or placebo. Beneficial effects of azithromycin treatment were independent from the presence of low (<1:32) or high (> or =1:32) CPn antibody titers.
  
  
  CONCLUSIONS
  Our findings indicate that treatment with azithromycin has a favorable effect on endothelial function in patients with documented coronary artery disease and evidence of CPn infection irrespective of antibody titer levels. Whether these favorable actions of antibiotic treatment will translate into a beneficial effect on atherogenesis and cardiac events needs further investigation.
authors.affiliation: Department of Cardiological Sciences, St George's Hospital Medical School, Cranmer Terrace, London, UK.
authors.forename: Nikhil
authors.initials: N
authors.lastname: Parchure
authors.forename: Emmanouil G
authors.initials: EG
authors.lastname: Zouridakis
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Kaski
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D000907:Antibodies, Bacterial / Q000097:blood / Q000187:drug effects; D017963:Azithromycin / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D001783:Blood Flow Velocity / Q000187:drug effects; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000187:drug effects / Q000503:physiopathology; D002097:C-Reactive Protein / Q000032:analysis; D023521:Chlamydophila Infections / Q000097:blood / Q000150:complications* / Q000188:drug therapy*; D003324:Coronary Artery Disease / Q000097:blood / Q000150:complications* / Q000503:physiopathology; D004311:Double-Blind Method; D019040:E-Selectin / Q000097:blood; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012698:Serologic Tests; D016896:Treatment Outcome; D014463:Ultrasonography; D014654:Vascular Patency / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects*; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D000900:Anti-Bacterial Agents; D000907:Antibodies, Bacterial; D015415:Biomarkers; D019040:E-Selectin; D014841:von Willebrand Factor; D017963:Azithromycin; D002097:C-Reactive Protein