ABSTRACT
HACEK is an acronym formed by the first letters of a group of bacterial species enjoined not only by their propensity to cause subacute endocarditis, but also for their requirement for increased (5-10%) CO2 (capnophilic) for growth. Species include Haemophilus aphrophilus, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens and Kingella species. E. corrodens and Kingella species cause a number of other serious infections, including abscesses, osteomeyelitis, and bacteremia. All species are part of the normal oral flora from where they may gain access to tissues, especially after dental manipulation. Definitive virulence factors have not been identified.
