Aggregatibacter actinomycetemcomitans

Aggregatibacter actinomycetemcomitans is a Gram-negative, facultative anaerobic bacterium that is a member of the HACEK group. It is primarily associated with periodontal diseases, and is also implicated in non-oral infections such as endocarditis and other systemic diseases.

Characteristics

Aggregatibacter actinomycetemcomitans is a small, non-motile, coccobacillary bacterium. It is oxidase positive and can ferment a variety of sugars to produce acid. The bacterium is also capable of producing a leukotoxin that is harmful to human immune cells.

Pathogenesis

Aggregatibacter actinomycetemcomitans is a significant pathogen in periodontal disease. It is particularly associated with localized aggressive periodontitis, a severe form of gum disease that occurs in adolescents and young adults. The bacterium adheres to oral surfaces and forms biofilms, which contribute to plaque formation and gum inflammation.

In addition to its role in oral disease, Aggregatibacter actinomycetemcomitans can also cause non-oral infections. It is one of the HACEK organisms, a group of Gram-negative bacteria that are a rare cause of endocarditis, an inflammation of the heart valves.

Treatment

Treatment of infections caused by Aggregatibacter actinomycetemcomitans typically involves antibiotics. The bacterium is usually sensitive to tetracycline, amoxicillin, and clindamycin. In cases of periodontal disease, treatment may also include mechanical cleaning of the teeth and gums to remove plaque and tartar.

See also

• Periodontal disease
• Endocarditis
• HACEK organisms