Bacteria may play a key role in the hardening of the arteries, known as atherosclerosis, according to a new study.
Researchers from the Columbia University College of Dental Medicine discovered bacteria called Enterobacter hormaechei in the arteries of a 78-year-old man who had previously suffered a heart attack. The bacteria were resistant to multiple antibiotics, and were present in high numbers in the man's diseased arterial tissue, according to the study.
Previously, it was tricky to understand the role of bacterial infections in cardiovascular disease, because researchers were unable to isolate live bacteria from atherosclerotic tissue.
But study researcher Dr .Emil Kozarov, of Columbia University, and his colleagues were able to isolate plaques from the man's tissue and grow the bacteria in lab dishes.
"Our findings warrant further studies of bacterial infections as a contributing factor to cardiovascular disease," and of the idea that bacteria in certain places could spread throughout the body, Kozarov said in a statement.
Researchers said such an infection could start when the bacteria are disseminated through openings in the vascular wall — for example, an infection could start in the intestines of a septic patient.
In the bloodstream, bacteria could spread through a "Trojan horse" effect, the researchers said. White blood cells that ingest harmful particles can internalize the E. hormaechei bacteria, but the bacteria can avoid immediate death once inside the cells.
From there, bacteria could penetrate the blood vessel walls, where they create secondary infections that can lead to atherosclerosis, the researchers said.
The bacteria could live in the body for long periods of time while traveling to and colonizing distant sites, the study said.
This can eventually lead to problems, including failure of antibiotic treatment, bacterial infection in the vascular tissues and inflammation, and atherosclerosis, which can lead to heart attack and stroke.
The study will be published in an upcoming issue of the Journal of Atherosclerosis and Thrombosis.
Pass it on: Bacterial infection may be associated with atherosclerosis, which is the hardening of the arteries.
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Follow MyHealthNewsDaily staff writer Amanda Chan on Twitter @AmandaLChan.
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