Capnocytophaga spp

• C. gingivalis
• C. granulosa
• C. haemolytica
• C. leadbetteri
• C. ochracea (previously CDC DF-1)
• C. sputigena

Gram Stain

•  Gram negative bacilli (facultative anaerobic)

Clinical Significance

These species are part of the commensal human oropharyngeal flora and may also colonize the female genital tract.  

They have been implicated as pathogens in periodontal disease and have been associated with intrauterine infections, amnionitis, neonatal infections, endocarditis, peritonitis, deep abscesses, septic arthritis, osteomyelitis, and ocular infections in both immunocompromised and immunocompetent individuals.

Usual Susceptibility Pattern

These organisms are typically susceptible to amoxicillin-clavulanate, macrolides, tetracyclines, quinolones, clindamycin, and carbapenems.

Susceptibility to narrow spectrum penicillin and cephalosporins is variable and clinical failures have been documented despite in vitro susceptibility.

Beta-lactamase production may also cause decreased susceptibility to all cephalosporins.

They are typically resistant to TMP/SMX, aminoglycosides, and colistin.