A particular strain of Stretococcus mutans is identified in Nature Communications this week as being associated with haemorrhagic stroke. The findings suggest that infection with this bacteria could be a risk factor for haemorrhagic stroke.
Koichiro Wada and colleagues show that certain types of the Streptococcus mutans bacterium can exacerbate a mouse model of stroke and can bind to damaged blood vessels in the mouse brain using a collagen binding protein. They found that oral bacteria isolated from human haemorrhagic stroke patients showed a higher frequency of bacteria expressing the collagen binding protein compared to controls and stroke patients with non-haemorrhagic stroke.
These finding suggest that certain bacteria contain virulence proteins that can worsen haemorrhagic stroke. These bacteria may also be potential risk factors for this condition.