Chlamydia pneumoniae in Atherosclerotic Lesions of Patients Undergoing Vascular Surgery

The pathophysiological implications of Chlamydia pneumoniae in atherosclerotic lesions and its contribution to atherosclerotic complications remain unclear. Therefore, the purpose of the present study was to evaluate whether or not there is an association between the presence of Chlamydia pneumoniae in atherosclerotic lesions and the clinical manifestations as well as risk factors of atherosclerotic disease in patients undergoing vascular surgery. Specimens from atherosclerotic arteries were collected during endarterectomy of the carotid artery (n = 15), endarterectomy of the femoral artery (n = 19), or repair of an abdominal aortic aneurysm (n = 28). Detection of Chlamydia pneumoniae was performed by using immunohistochemical staining (IHC) with specific antibodies. Clinical manifestations of atherosclerotic disease were defined by the presence of cardiovascular risk factors, coronary heart disease, and previous vascular surgery. Inflammatory serum markers were determined in all patients prior to surgery. The specimens of all 62 patients revealed severe atherosclerosis in histological examination and a positive IHC was observed in 41 samples (66%). There were no differences regarding cardiovascular risk factors, coronary heart disease, events of previous vascular surgery, or inflammatory serum markers when comparing patients with positive and negative IHC. In conclusion, our findings showed no correlation between clinical or laboratory parameters of atherosclerosis and the presence of Chlamydia pneumoniae in atherosclerotic lesions. Therefore, Chlamydia pneumoniae appears to be a concomitant phenomenon rather than a causative principle in atherosclerosis.