Peptostreptococcus species

Peptostreptococcus species

Background:

Peptostreptococcus:

•  Anaerobic, Gram-positive, non-spore forming bacteria.
• Cells are small, spherical, and can occur in short chains, in pairs or individually.
• Peptostreptococcus are slow-growing bacteria with increasing resistance to antimicrobial drugs.
• Most frequently identified species of Peptostreptococcus is P. magnus.
• Peptostreptococcus species are commensal organisms in humans, living predominantly in the mouth, skin, gastrointestinal, vagina and urinary tracts, and compose a portion of the bacterial gut flora.
• Under immunosuppressed or traumatic conditions these organisms can become pathogenic, as well as septicemic, harming their host.
• Peptostreptococcus can cause brain, liver, breast, and lung abscesses, as well as generalized necrotizing soft tissue infections.
• Anaerobic gram-positive cocci such as Peptostreptococcus are the second most frequently recovered anaerobes and account for approximately one quarter of anaerobic isolates found.

Therapy:

1. Amoxicillin Usual: 250-500 mg orally three times daily or 500-875mg bid.
2. Augmentin 875/125 mg orally twice daily or  500/125mg three times daily or 1000mg XR (2 tabs=2000mg) q12h   OR  Ampicillin-sulbactam (Unasyn®) 1.5 – 3.0 grams IV q6h
3. Penicillin VK 500mg orally every 6 hours  OR  Penicillin G 1-2 million units IV q6h
4. Several others but considered ‘overkill’  e.g. Piperacillin-Tazobactam, Vancomycin, Imipenem, Daptomycin, Linezolid.