Detection of Chlamydia pneumoniae (Chlamydophila pneumoniae) DNA in atherosclerotic plaques and its molecular analysis in northern Greece

Objectives : C. pneumoniae responsible for respiratory tract infections has also been assocciated with chronic diseases such as atherosclerosis.The aim of the present study is the detection of C. pneumoniae DNA in various atherosclerotic arteries by a sensitive and specific PCR. In order to investigate whether there is a relation between a specific type and atherosclerosis, genotyping was performed. Methods: The study group consisted of 122 atherosclerotic plaques from patients (mean age 68.4, range 50-89 years old, 95 males and 25 females) with severe atherosclerosis. C. pneumoniae DNA was detected in atherosclerotic plaques by nested «Touchdown» PCR. A second PCR targeting the ygeD-urk intergenic region was performed and PCR products were sequenced.Results: 12.3% of the specimens were positive for C. pneumoniae. Detection rates in specimens of carotid, abdominal, and femoral arteries were 12%, 15.6%, and 10%, respectively. (p = NS). 14 strains were found to have 100% homology with J138, AR39 and TW-183, while one strain had a 23 bp invertible region and revealed 100% homology with the CWL029. Conclusion : Overall, 15/122 (12.3%) atherosclerotic specimens from patients were positive for C. pneumoniae. The strains detected belong to two different types designated as genotype I and II. Genotype I was the prevalent and only one strain had the reverse orientation of the 23bp region in northern Greece.