Anaerobic Gram positive cocci (other)

• Anaerococcus spp
• Anaerosphaera spp
• Atopobium spp
• Blautia spp
• Finegoldia spp
• Gallicola spp
• Murdochiella spp
• Parvimonas spp
• Peptococcus spp
• Peptoniphilus spp
• Peptostreptococcus spp
• Ruminococcus spp
• Slackia spp

Clinical Significance

These organisms are part of normal skin and oropharynx flora and can cause various infections (monomicrobial or polymicrobial) including brain abscesses, pleuropulmonary infections, chronic sinusitis, mastoiditis, bacteremia (immunocompromised / post surgical), osteomyelitis, arthritis, medical device related, skin/soft tissue infections (myositis/fasciitis), and obstetrical/gynecological infections.

Usual Susceptibility Pattern

Most anaerobic cocci (except Peptostreptococcus anaerobius) are susceptible to penicillin.

Penicillin resistance has also been rarely noted in F. magna (previously P. magnus), P. micra, and P asaccharolyticus. 

Carbapenems and metronidazole are very active against anaerobic Gram positive cocci. 

Metronidazole resistance should prompt aerotolerance testing and further identification to rule out aerotolerant / microaerophilic streptococci. 

Clindamycin resistance is significant. 

Rifampin resistance has been reported.

Cephalosporins, macrolides, tetracyclines, and quinolones do not have reliable activity.

Linezolid, although not well studied, appears to have activity against many anaerobic Gram positive cocci.