Eikenella

The only known representative of this genus is Eikenella corrodens, which was discovered in 1958 by M. Eiken. It is a gram-negative facultative anaerobic rod. In humans, it can be isolated as a commensal from the oral cavity, gastronitestinal system or female urogenital system. Eikenella is classified in the HACEK group  (some species of the genus Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella), based on similarity in cultivation requirements.

Cultivation
For growth under aerobic conditions, this bacterium requires the presence of hemin (factor X) in the culture medium, it grows better in an atmosphere enriched with carbon dioxid. On solid culture media, we observe the growth of gray small colonies of two types, namely corroding colonies that grow into agar and non-corroding colonies. In one culture, we can observe both types at the same time. Growth can be accompanied by the smell of chlorine. Eikenella is oxidase-positive, catalase-negative, reduces nitrate.

Diseases
Eikenella corrodens has been isolated from periapical and periodontal abscesses or gingivitis. Furthermore, this bacterium plays a role in the etiology of brain abscesses, otitis, sinusitis, aspiration pneumonias and lung abscesses, it can be an infectious agent of endocarditis, skin infections, prostatitis or sepsis. It is also used as a pathogen in mixed infections, for example in patients with cancers in head and neck area, and is often observed in the wound by a bite (vulnus morsum). It is also an etiological agent in needle-licker's osteomyelitis, which is osteomyelitis in patients with IDM* or intravenous drug users who lick needles before using them.

* from French - infarctus du myocarde

Therapy
Eikenella is resistant to lincosamides, metronidazole, amynoglycosides and vancomycin. Cefoxitin and cefuroxin are suitable for therapy. It is sensitive to penicilin, tetracycline and cephalosporins.

Extern links

 * Eikenella corrodens (english wikipedia)

Literature



 * BEDNÁŘ, Marek. Lékařská mikrobiologie : bakteriologie, virologie, parazitologie. 1. edition. 1996.


 * JULÁK, Jaroslav. Úvod do lékařské bakteriologie. 1. edition. Praha : Karolinum, 2006.  ISBN 80-246-1270-4.


 * VOTAVA, Miroslav, et al. Lékařská mikrobiologie speciální. 1. edition. Brno : Neptun, 2003. 495 s.  ISBN 80-902896-6-5

Category: Microbiology