Diversity of Streptococcus mutans serotypes isolated from dental plaque of Brazilian patients with a history of acute myocardial infarction.

BACKGROUND

Streptococcus mutans serotypes (c, e, f, k) are linked to dental caries, with less common serotypes (e, f, k) and collagen-binding genes (CBG: cnm and cbm) suggested to be associated with cardiovascular diseases.

OBJECTIVE

This study investigated the presence of S. mutans serotypes and collagen-binding genes (CBGs) in dental plaque and their possible association with acute myocardial infarction (AMI) in adults.

METHODOLOGY: A total of 31 infarcted and 17 non-infarcted patients underwent oral and blood examinations. DNA from plaque samples was analyzed using PCR to identify S. mutans serotypes and cnm/cbm genes. S. mutans was detected in 22.6% (7/31) of infarcted patients and 11.8% (2/17) of non-infarcted patients.

RESULTS

Serotype c was the most prevalent in infarcted patients (57.1%, 4/7), followed by e (42.9%, 3/7) and k (14.3%, 1/7); serotype f was not detected. Only serotype c was found in non-infarcted patients. Less common serotypes (e, k) and co-occurring serotypes (c, k) were exclusive to infarcted patients. No CBGs were detected in any serotypes. No association was found between S. mutans and dental caries in either group. Patients with cholesterol levels <190 mg/dL and no S. mutans had a 47.4% lower risk of infarction.

CONCLUSION

Although S. mutans, including less common serotypes, was more prevalent in infarcted patients, no significant association with AMI was observed. Further research is needed to elucidate the role of S. mutans in cardiovascular diseases.