CHLAMYDIA-PNEUMONIAE, CYTOMEGALOVIRUS, AND HERPES-SIMPLEX VIRUS IN ATHEROSCLEROSIS OF THE CAROTID-ARTERY

Background Chlamydia pneumoniae and the herpes viruses cytomegalovirus (CMV) and herpes simplex virus type 1 (HSV-1) have been associated wi th human atherosclerosis in seroepidemiological and separate histopath ological studies. We investigated the concurrent presence of these mic roorganisms in patients undergoing carotid endarterectomy. Methods and Results Endarterectomy specimens from 76 patients with carotid artery stenosis were stained for C pneumoniae, CMV, and HSV-1 particles with specific IgG monoclonal antibodies by the avidin-biotin-peroxidase me thod. IgG antibodies to CMV and C pneumoniae were also measured in the serum. These were correlated with plaque morphology and the presence of the microorganisms in the atherosclerotic plaques. C pneumoniae was detected in 54 (71%) (95% confidence interval [CI], 59.5% to 80.9%), CMV was detected in 27 (35.5%) (CI, 24.9% to 47.3%), and HSV-1 was det ected in 8 (10.5%) (CI, 4.7% to 19.7%) versus none of 20 (0%) control normal carotid artery and aortic tissue (autopsy) specimens (CI, 0% to 16.8%) (P < .001 for CMV and C pneumoniae). At least one microorganis m was detected in 59 of the specimens (77.6%) (CI, 66.6% to 86.4%), wi th a single microorganism present only in 35 (46%), two microorganisms present in 18 (23.7%) (CI, 14.7% to 34.8%), and all three present inp (7.9%) (CI, 3.0% to 16.4%). Atherosclerotic plaques with thrombosis w ere more likely to have C pneumoniae (80.4%) or CMV (57.8%) than were plaques without thrombosis (56.7% and 16.7%, respectively; P = .04 and .007). There was no correlation between the presence of CMV and C pne umoniae in the atherosclerotic vessels and serum antibody titers. Conc lusions C pneumoniae and CMV are commonly detected in atherosclerotic plaques of the carotid arteries, but their presence cannot be predicte d by measuring serum antibodies. The presence of these microorganisms may predispose to a greater risk of thrombosis in the plaques, but fur ther studies are needed to confirm this observation.