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Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells
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The connection between ruptured cerebral aneurysms and odontogenic bacteria
Mikko J Pyysalo1, Liisa M Pyysalo, Tanja Pessi
1Department of Oral and Maxillofacial Diseases, Tampere University Hospital, , Tampere, Finland.
Journal of Neurology, Neurosurgery, and Psychiatry
|June 14, 2013
Summary
Oral bacteria DNA was found in over half of ruptured intracranial aneurysm samples, suggesting dental infections may contribute to aneurysm disease and subarachnoid hemorrhage risk.
Area of Science:
- Neurology
- Infectious Diseases
- Cardiovascular Research
Background:
- Ruptured intracranial aneurysms are linked to higher mortality from cerebrovascular and cardiovascular diseases.
- Chronic inflammation is a feature of ruptured intracranial aneurysms, similar to other vascular conditions.
- The role of bacterial infections in aneurysm development, particularly from oral sources, remains understudied.
Purpose of the Study:
- To detect oral and pharyngeal bacterial genomes in ruptured intracranial aneurysms.
- To investigate dental infection as a potential risk factor for subarachnoid hemorrhage.
Main Methods:
- Analysis of 36 ruptured aneurysm specimens (surgical and autopsy).
- Real-time quantitative PCR used to identify bacterial DNA from oral species.
- Immunohistochemical staining for bacterial receptors (CD14, TLR-2) performed on select cases.
Main Results:
- Bacterial DNA identified in 58% of aneurysm specimens.
- Endodontic and periodontal bacteria DNA found in 56% and 47% of samples, respectively.
- Streptococcus mitis group DNA was most prevalent; common periodontal pathogens were also detected.
Conclusions:
- This study provides initial evidence linking dental infections to the pathophysiology of intracranial aneurysms.
- Findings suggest a potential role for oral bacteria in the development of ruptured intracranial aneurysms.
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