Chlamydia pneumoniae in atherosclerotic middle cerebral artery

Background and Purpose-Atherosclerotic middle cerebral arteries are frequen t sites of thrombosis, leading to stroke. Previous studies have suggested a role for Chlamydia pneumoniae in the pathogenesis of atherosclerosis. Howe ver, the presence of this pathogen in atherosclerotic middle cerebral arter ies has heretofore not been documented. In the present study, we analyzed a theromatous plaques from middle cerebral arteries for the presence of C pne umoniae. Methods-Atherosclerotic middle cerebral arteries from 15 cadavers who died of natural causes and corresponding nonatherosclerotic arteries from 4 othe rwise healthy trauma victims were examined. Assays for C pneumoniae DNA wer e carried out by nested polymerase chain reaction (nPCR) specific for the C pneumoniae ompA gene. The presence of the bacterium was assessed by transm ission electron microscopy. Results-Five of the 15 atherosclerotic arterial samples and none of the con trol tissues were positive for C pneumoniae by nPCR. Particles similar in m orphology and size to C pneumoniae elementary bodies were detected by trans mission electron microscopy in 4 of the 5 nPCR-positive atherosclerotic sam ples. Conclusions-The demonstration of C pneumoniae in atherosclerotic middle cer ebral arteries is consistent with the hypothesis that this bacterium is inv olved in acute and chronic cerebrovascular diseases.