Clostridium species

Clostridium species

Background:
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Anaerobic Gram-positive bacilli
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>Clostridium species:
     1] Clostridium difficile
     2] Clostridium perfringens
     3] Clostridium tetani

Clostridium:

  • Gram-positive bacteria, obligate anaerobes capable of producing endospores.
  • Rod-shaped.
  • Consists of approximately 100 known species that include common free-living bacteria as well as important pathogens.
  • There are five main species responsible for disease in humans.
    • C. botulinum: produces botulinum toxin in food/wound and can cause botulism.
    • C. difficile: can flourish when other bacteria in the gut are killed during antibiotic therapy, leading to pseudomembranous colitis.
    • C. perfringens: Causes a wide range of symptoms, from food poisoning to gas gangrene. 
    • C. tetani:  causative organism of tetanus.
    • C. sordellii: can cause a fatal infection in exceptionally rare cases after medical abortions.

Therapy:
Important considerations:  The choice of an agent should be based on local antimicrobial sensitivities, site of infection, cost, and comorbid conditions.   Generally, the most common agents/regimens are listed first.   Listed dosages may need to be adjusted for renal dysfunction.

Clostridium difficile:

  1. Metronidazole 500 mg po three times daily or 250 mg four times daily x 10 to 14 days (For initial oral antibiotic treatment of mild to moderate disease only).
  2. Severe disease:  Vancomycin 125 mg orally four times daily x 10 to 14 days (may be increased to 500 mg 4 times daily)  OR   Fidaxomicin 200 mg po bid x 10 days
  3. Pulsed oral vancomycin for relapse e.g.:  125 mg orally four times daily for 7 to 14 days, then 125 mg orally twice daily for 7 days, then 125 mg orally once daily for 7 days, then 125 mg orally every other day for 7 days, and finally vancomycin 125 mg orally every 3 days for 14 days.
  4. Relapse:  Vancomycin 125 mg orally four times daily x 14 days, followed by rifaximin 400 mg bid x 14 days

Clostridium perfringens:

  1. Penicillin G 2-4 million units IV q4-6h +/-  Clindamycin  600mg IV every 6 or 8 hours or 300mg orally four times daily 
  2. Several agents:
  3. Azithromycin
  4. Ampicillin 2 grams IVPB every 4-6 hours
  5. Ampicillin-sulbactam (Unasyn) 1.5 – 3.0 grams ivpb q6h
  6. Cefazolin 1 gram IVPB q8h
  7. Ceftriaxone 1-2 grams IV q24h
  8. Cefepime 2 grams IV every 12 hours
  9. Piperacillin-tazobactam 3.375g ivpb q6h
  10. Doxycycline 100mg orally twice daily
  11. Vancomycin 1 gram  ivpb q12h (patient-specific dosing required)
  12. Linezolid 600 mg orally or IV q 12h
  13. Chloramphenicol 50-100 mg/kg/day in divided doses every 6 hours (Maximum daily dose is 4 grams e.g. 1 gram q6h)
  14. Imipenem 500mg IV every 6 hours.

Clostridium tetani:

  1. Metronidazole 500 mg IV every six to eight hours
  2. Doxycycline 100 mg IV q12h
  3. cefazolin 1 to 2 g IV every eight hours
  4. Ceftriaxone 1-2 grams IV q24h
  5. Vancomycin 1 gram  ivpb q12h (patient-specific dosing required)
  6. Chloramphenicol 50-100 mg/kg/day in divided doses every 6 hours (Maximum daily dose is 4 grams e.g. 1 gram q6h)
Clostridium species