Chlamydia pneumoniae infection as a risk factor for accelerated atherosclerosis in hemodialysis patients

Atherosclerotic cardiovascular disease is the main cause of morbidity and mortality for end-stage renal disease patients undergoing chronic haemodialysis (HD). Several studies in recent years have identified Chlamydia pneumoniae, a respiratory pathogen, as risk factor for cardiovascular diseases in the general population. The aim of our study is to evaluate chlamydial load, in peripheral blood mononuclear cells (PBMC) of HD patients. Furthermore, the correlation between DNA chlamydial load and markers of inflammation was also examined. PBMC specimens isolated from 49 HD patients and 46 blood donors were analyzed for the presence of C. pneumoniae DNA by real-time PCR and ompA nested touchdown PCR. In HD patients, plasma levels of several inflammatory markers were also determined. A significantly higher rate of C. pneumoniae DNA was found in HD patients (44.9 percent) than in blood donors (19.6 percent) (p=0.016); HD patients were also more likely to have a significantly high chlamydial load (p=0.0004). HD patients with atherosclerotic cardiovascular diseases have a significantly greater chlamydial load than HD patients without cardiovascular diseases (p= 0.006). A significantly higher value of C-reactive protein, IL-6 and advanced oxidative protein products was found in HD patients with a greater chlamydial load (p less than 0.05). Likewise, a significantly lower monocyte HLA-DR percentage (p=0.011) as well as a lower monocyte HLA-DR expression were found in such patients (p= 0.007). In conclusion, our results show that HD patients are at high risk of C. pneumoniae infection correlated with chronic inflammatory response which in turn can lead to accelerated atherosclerosis and other long-term clinical complications such as myocardial infarction and stroke.