Day #239 - Clostridium Difficile (C. Diff)

Today we discussed a case of severe Clostridium difficile associated diarrhea. I have previously blogged about the differential of colitis here.

There is a general review of C. difficile available from last week's JAMA. I prefer these two (#1 and #2) editorials by John Bartlett.

A full suppliment to the journal Clinical Infectious Diseases was devoted to C. difficile in January 2008 and it is very good.

Diagnosis of C. Diff

Microbiology

• At our hospital, the C. diff toxin assay (EIA) detects toxins A and B and has ~70% sensitivityon a single test, with ~90-95% sensitivity on three tests. The specificity greater than 95%.
• The most sensitive assay is the test for cytopathic effect, which is not available
• You can also culture Clostridium difficile from the stool, although most laboratories no longer do this, and just because you grow it does not necessarily mean that it is causing disease

CT Scan

• May show thickening of the bowel wall, colitis, ileus. "Double Halo" and "Accordian Signs"
  

Sigmoid/Colonoscopy

• May see pseudomembranes diagnostic of pseudomembranous colitis

Treatment of First Episode

• If possible stop offending antibiotics
• Mild/Moderate Disease
  
  • Metronidazole OR Vancomycin (PO) duration 10-14d
    
• Severe Disease
  
  • Defined as:
    
    • Two of (Age above 60, Febrile, WBC above 15, Albumin below 25)
      
    • OR hypotension/shock or Cr greater than 1.5x normal, or toxic megacolon, peritoneal signs, perforated bowel
      
  • Infectious Disease +/- General Surgery Consultation
  • ICU Consult for patients with hemodynamic comprimise
    
  • Vancomycin (PO) unless severe illeus, then Metronidazole (IV) duration 10-14d
    

Relapse

• First relapse --> can repeat last treatment depending on severity
• Second relapse --> vancomycin taper (see JAMA article). ID consult.