Chlamydia pneumoniae in vascular tissue

This review summarizes the evidence for the presence of Chlamydia pneumoniae organisms in atherosclerotic lesions. A total of 17 publications are mentioned concerning this topic. In all but two, both from the same group, evidence is presented by means of various techniques for the existence of the organisms in atherosclerotic tissue. Thus, they have been found in the aorta and in coronary, carotid, pulmonary, femoral and iliac arteries. In the first study in the UK, the aorta, femoral and iliac arteries were found to be positive for C. pneumoniae. In a recent study on autopsy specimens undertaken in conjunction with South African investigators, 71% of atheromatous arteries were positive for C. pneumoniae compared with only 9% of non-atheromatous arteries. Interestingly, the organisms were detected in 67% of the vessels showing only early atherosclerotic lesions (fatty streaks). The relationship between the age of the subject and the probability of detecting C. pneumoniae organisms is discussed; the youngest subjects with arteries positive for these organisms were aged 15 and 20 years. It is concluded that the presence of chlamydiae within atherosclerotic lesions is now beyond doubt, but as yet there is no conclusive evidence for a causal role in atherosclerosis. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.