Clostridium difficile

Clostridium difficile

Updated: 02/03/2024

© Jun Wang, MD, PhD

 

General features

  • Gram-positive, anaerobic, sporogenic bacterium
  • May be part of normal colonic flora
  • Most common cause of pseudomembranous colitis
  • Most commonly nosocomial infectious diarrhea in the U.S.
  • Colitis due to overgrowth and exotoxin production
  • Results of interruption of normal colonic flora by antibiotics, chemotherapy or immunosuppression, etc

Pathogenesis

  • Disruption of normal colonic flora
  • Colonization of C. Diff
  • Production of exotoxins
    • Toxin A: Enterotoxin, mucosal injury, fluid loss and inflammation, granulocyte attractant
    • Toxin B: Cytotoxin, cytopathic

Key clinical features

  • Fever, abdominal pain and cramping
  • Green foul-smelling diarrhea
  • May perforate and cause septic shock

Colonoscopic findings

Pathologic findings

Diagnosis

  • History of hospitalization and antibiotics use
  • Image studies (CT)
  • Colonoscopy
  • Fecal assay for exotoxin A and B (immunoassay or molecular tests)
    • Most strains produce both toxins A and B, although some strains produce only one toxin

Treatment

  • Supportive
  • Antibiotics: Metronidazole and vancomycin
  • Surgery for fulminant cases

 

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