Relationship between Cnm-positive Streptococcus mutans and cerebral microbleeds in humans

Oral Dis. 2015 Oct;21(7):886-93. doi: 10.1111/odi.12360. Epub 2015 Sep 1.

Abstract

Objective: Cerebral hemorrhage has been shown to occur in animals experimentally infected with Streptococcus mutans carrying the collagen-binding Cnm gene. However, the relationship between cerebral microbleeds and oral hygiene, with a focus on Cnm gene-positive S. mutans infection, remains unclear.

Material and methods: One hundred and thirty-nine subjects participated. The presence or absence of Cnm-positive S. mutans and its collagen-binding activity were investigated using saliva samples, and relationship with cerebral microbleeds detected on MRI investigated, including clinical information and oral parameters.

Results: Fifty-one subjects were identified as Cnm-positive S. mutans carriers (36.7%), with cerebral microbleeds being detected in 43 (30.9%). A significantly larger number of subjects carried Cnm-positive S. mutans in the cerebral microbleeds (+) group. S. mutans with Cnm collagen-binding ability was detected in 39 (28.1%) of all subjects, and the adjusted odds ratio for cerebral microbleeds in the Cnm-positive group was 14.4. Regarding the presence of cerebral microbleeds, no significant differences were noted in the number of remaining teeth, dental caries, or in classic arteriosclerosis risk factors.

Conclusions: The occurrence of cerebral microbleeds was higher in subjects carrying Cnm-positive S. mutans, indicating that the presence of Cnm-positive S. mutans increases cerebral microbleeds, and is an independent risk for the development of cerebrovascular disorders.

Keywords: Cnm-positive Streptococcus Mutans; Magnetic Resonance Imaging; collagen-binding protein; intracranial hemorrhage; microbleeds; stroke.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adhesins, Bacterial / genetics*
  • Aged
  • Carrier Proteins / genetics*
  • Carrier State / diagnosis
  • Carrier State / microbiology*
  • Cerebral Hemorrhage / diagnostic imaging
  • Cerebral Hemorrhage / epidemiology*
  • Collagen / metabolism
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Oral Hygiene
  • Saliva / metabolism
  • Saliva / microbiology*
  • Streptococcal Infections / diagnosis
  • Streptococcal Infections / microbiology*
  • Streptococcus mutans / genetics*
  • Streptococcus mutans / metabolism

Substances

  • Adhesins, Bacterial
  • Carrier Proteins
  • Cnm protein, Streptococcus mutans
  • Collagen