A Potential New Risk Factor for Stroke: Streptococcus Mutans With Collagen-Binding Protein.

Area of Science:

• Neurology
• Microbiology
• Vascular Medicine

Background:

• Certain oral bacteria, Streptococcus mutans (SM), possess a collagen-binding protein (Cnm).
• These SM strains are associated with platelet aggregation inhibition and matrix metalloproteinase-9 activation.
• Previous research suggested a potential link between these SM strains and intracerebral hemorrhage risk.

Purpose of the Study:

• To investigate the clinical details of patients with cerebrovascular diseases and intracranial aneurysms.
• To determine if Cnm-positive Streptococcus mutans are associated with specific neurological conditions.
• To explore potential risk factors for these conditions.

Main Methods:

• Saliva samples were collected from 429 patients with various neurological conditions (CES, non-CES infarct, ICH, RIA, UIA) and 79 healthy volunteers.
• Cnm-positive Streptococcus mutans were identified by detecting the Cnm gene.
• Statistical analysis was performed to compare Cnm-positive SM rates and known risk factors.

Main Results:

• A significantly higher prevalence of Cnm-positive Streptococcus mutans was found in patients with cardioembolic stroke (CES), non-CES infarct, intracerebral hemorrhage (ICH), and ruptured intracranial aneurysm (RIA).
• No correlation was observed between Cnm-positive SM and traditional risk factors like hypertension, diabetes, hyperlipidemia, smoking, or alcohol consumption.

Conclusions:

• Specific oral Streptococcus mutans strains carrying the Cnm protein may serve as a risk factor for cardioembolic infarct, intracerebral hemorrhage, and ruptured intracranial aneurysms.
• These findings suggest a potential link between oral microbiome and cerebrovascular/intracranial aneurysm pathologies.
• Further research is warranted to elucidate the precise mechanisms and clinical implications.