Oro-dental bacteria in various atherosclerotic arteries.

Chlamydia pneumoniae DNA has been detected in at least 40% of all major arteries affected by atherosclerosis, but several other microorganisms have also been detected. In this study, diseased vessels were evaluated for the presence of the DNA of seven oro-dental bacteria and two nonoral bacteria. A polymerase chain reaction technique was employed using primer pairs based on 16S rRNA genes. Of 32 specimens tested, 10 (31.2%) were DNA positive: seven for Actinobacillus actinomycetemcomitans and three for Prevotella intermedia. The DNA was found in specimens from the aorta and the iliac, internal mammary and coronary arteries. Eleven (35.4%) of 31 specimens had been shown previously to be positive for Chlamydia pneumoniae DNA. A mixture of chlamydiae and oro-dental bacteria was found in three cases. These findings may have implications for antibiotic prophylaxis of coronary heart disease if directed solely at Chlamydia pneumoniae.