Aerococcus spp

• A. christensenii
• A. sanguinicola
• A. urinae
• A. urinaehominis
• A. viridans

Gram Stain

• Gram positive cocci in pairs/tetrads/clusters (aerobic)

Clinical Significance

These organisms are found on skin, female genital tract and environmental surfaces.

A. christensenii - recovered from vaginal specimens.

A. sanguinicola - associated with urosepsis and endocarditis.

A. viridans - associated with bacteremia, meningitis, endocarditis, osteomyelitis, septic arthritis and pleuropulmonary infections.

A. urinae - associated with urinary tract infections and rarely with endocarditis, septicemia and peritonitis.

A. urinaehominis - implicated in urinary tract infections.

Usual Susceptibility Pattern

These organisms are typically susceptible to penicillin, amoxicillin and vancomycin. Ceftriaxone may be less active than amoxicillin/ampicillin.

Penicillin and/or ceftriaxone resistance has been described in A. viridans.

Susceptibility to clindamycin, tetracyclines, quinolones, and TMP/SMX is variable.

Fosfomycin is not reliable.