Additional Sites of Infection
Necrotizing fasciitis - involving facia and a life threatening emergency, these are also usually mixed anaerobic infections, seen most commonly in diabetic patients.
Diabetic foot ulcers - almost always a mixed infection of aerobes and anaerobes in diabetic ulcers (a common malady).
Bone - occasional/rare cause of bone infection (osteomyelitis), and usually found as a single pathogen. The source is usually contiguous soft tissue infection.
These organisms are frequent causes of oral infections including gingivitis, Vincent's angina, and tooth abscess. It is not clear how often, and what significance their role in infections is but they are frequently isolated. The most important aspect of disease associated with P. melanogenica is it's resistance to penicillin (see below). Most oral infections are treated with penicillin.
Other diseases associated with the oral Prevotella species includes brain abscess, and lung abscess. P. melanogenica is more often isolated than B. fragilis in these infections.
These organisms are important constituents of normal flora of vagina. Although they are not the most common organism in vaginal flora, they account for 2/3 of pelvic abscesses. Typical infections involving these organisms include - tubo-ovarian abscess, post cesarean section, and vaginal hysterectomy. Less common are salpingitis or endometritis without abscess formation.
Fusobacterium nucleatum is the most common human pathogen of this genus. It is a spindle shaped gram negative resident of the oral cavity and colon.