Clostridium difficile

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Bacteria - Gram Positive

Clostridium difficile

Characteristics
- Common to all bacteria in Clostridia family
- Gram + rods
- Obligate anaerobe
- Spore-forming
Exposure/Risk Factors
- Antibiotics (esp. broad-spectrum)
  - C. diff is small part of normal gut flora; killing other gut flora by antibiotics creates opportunities for C. diff. to overgrow
  - Commonly associated with clindamycin and ampicillin use
Produces 2 toxins
- Enterotoxin A
  - Disrupts tight junctions of gut to alter fluid secretion in gut
    - Leads to intestinal inflammation (enterotoxic)
    - Causes watery diarrhea
- Cytotoxin B
  - Disrupts cytoskeleton via actin depolymerization to kill cells
    - Leads to cell death (cytotoxic)
    - Causes colonic epithelial necrosis, inflammation, and fibrin deposition (colitis)
Presentation
- Watery diarrhea
- Pseudomembranous colitis
  - White/yellow plaques on colonoscopy
  - marked thickening of the colonic wall (accordion sign), irregularity of bowel wall, pericolonic stranding on CT
- Abdominal pain, weight loss, malaise, dehydration may also be seen
Treatment
- Contact precautions must be used
  - Non-sterile gloves and gown
- Vancomycin or Metronidazole
  - First-line treatment for isolated C. diff infection
- Fidaxomicin
  - Used primarily for recurrent infections