Endothelial function parameters in patients with unstable angina and infection with Helicobacter pylori and Chlamydia...

Endothelial dysfunction may be a factor linking infection with atherosclerosis. The aim of our study was to assess the relationship between seropositivity to Helicobacter pylori (Hp) and/or to Chlamydia pneumoniae (Cp) and some endothelial function parameters in patients with unstable angina.

In 31 patients with unstable angina, we determined the serum concentration of the von Willebrand factor (vWF), thrombomodulin, tissue plasminogen activator antigen, and tissue plasminogen activator inhibitor type 1 antigen, the concentration of IgG antibodies to Hp and Cp (all by ELISA), and the level of C-reactive protein. The Western blot test was performed for all patients seropositive to Hp. It allowed us to identify 15 different antigen proteins of Hp.

Sixty-one percent of the patients were seropositive to both Hp and Cp, and 35% were seropositive to Hp only. We did not find significant differences in serum concentrations of endothelial function parameters and CRP between the two groups of patients. The patients seropositive to both Hp and Cp had a significantly higher serum concentration of vWF when Hp did not contain the 95 kDa protein (p=0.01) and a significantly higher serum concentration of PAI-1:Ag when Hp did not contain the 57 kDa protein (p=0.002) and the 66 kDa protein (p=0.02).

The results show that the antigenic profile of bacteria may play a more significant role in coronary artery disease than seropositivity.