Association between Chlamydia pneumoniae and atherosclerotic lesions.

There can no longer be any doubt that viable Chlamydia pneumoniae organisms are present in atherosclerotic lesions. Indeed, the endovascular presence of C. pneumoniae in coronary artery disease (CAD) is common. The fact that this lesion, which is the major cause of stroke, coronary heart disease ( CHD), peripheral vascular disease and aortic aneurysm, can no longer be regarded as sterile has prompted a good deal of study and speculation. Atherosclerotic lesions have been studied in detail, but until recently histological descriptions of the lesion have not included C. pneumoniae organisms. Reviews and analysis of the literature confirm the association between C. pneumoniae and atherosclerotic lesions and CHD. The possibility that C. pneumoniae plays a causal or contributory role in the development of atherosclerotic lesions has been debated. It is of major importance as there is already evidence that antibiotic therapy may be of clinical benefit in patients with CHD. Large clinical trials using antichlamydial agents have been embarked upon which may provide further evidence of a causal role for C. pneumoniae. The underlying mechanism of how C. pneumoniae contributes to lesions and the effect of antibiotic therapy on lesions remain unknown. The association between C. pneumoniae and atherosclerosis is reviewed. Particular attention is paid to the lesion itself and the presence of C. pneumoniae. Potential areas of study that may contribute to this rapidly expanding area of research is explored.