Aggregatibacter

Aggregatibacter is a genus of Gram-negative bacteria belonging to the family Pasteurellaceae. The genus was created in 2005 by reclassifying several species previously placed in the genus Actinobacillus. The most well-known species within this genus is Aggregatibacter actinomycetemcomitans, which is a common inhabitant of the human oral cavity and is associated with localized aggressive periodontitis, an inflammatory gum disease.

Aggregatibacter species are facultative anaerobes, meaning they can grow in the presence or absence of oxygen. They are typically non-motile and have a coccobacillary or rod-shaped morphology. These bacteria are often found as part of the normal flora in the oral cavity of humans and animals. However, under certain conditions, they can become opportunistic pathogens.

Beyond periodontal disease, Aggregatibacter species have been implicated in other infections, including endocarditis, abscesses, and systemic infections, particularly in immunocompromised individuals. Diagnosis typically involves culturing and identifying the bacteria from clinical specimens. Treatment for infections caused by Aggregatibacter often involves antibiotics, with susceptibility testing being important due to potential resistance mechanisms. Research continues to explore the virulence factors and pathogenic mechanisms of Aggregatibacter species to better understand and combat the diseases they cause.