Serological evidence of Chlamydia pneumoniae lipopolysaccharide antibodies in atherosclerosis of various vascular regions

The role of Chlamydia pneumoniae in the pathogenesis of atherosclerosis has so far mainly been investigated in patients suffering from coronary heart disease; the other vascular regions have virtually been ignored. The aim of this study was to carry out a statistical survey of serological markers of a C. pneumoniae infection in patients with different patterns of atherosclerosis manifestation. 340 patients were examined for the atherosclerotic alteration of peripheral arteries of the lower limbs, carotid arteries and coronary arteries by ultrasound scan and/or angiography. Immunoglobulin(Ig)G and IgA-rELISA were used to measure chlamydial lipopolysaccharide antibodies. Species determination was performed using the IgG micro-immunofluorescence test. 24.0% of atherosclerotic cases (A) and 52.3% of controls (C) were negative for C. pneumoniae lipopolysaccharide antibodies (p = 0.00002). By contrast, 45.1% of atherosclerotic cases and 16.9% of controls were positive for both IgG and IgA (p = 0.00002). The mean antibody titers of the atherosclerosis group were higher than in the control group (IgG positive xAIgG = 344, xCIgG = 272; IgG and IgA positive xAIgG = 576, xCIgG = 486 and xAIgA = 120, xCIgA = 91). Concerning atherosclerosis manifestation in various vascular regions, no significant differences were found between IgG and IgA antibody titers and prevalence. The results show that a persistent C, pneumoniae infection with evidence of lipopolysaccharide immunoglobulin G and A is equally associated with the atherosclerotic alteration of coronary arteries, carotid arteries and peripheral arterial occlusive disease, irrespective of the severity of atherosclerosis and with no predisposition to any particular vascular region.