II. Indications for testing

  1. Diarrheal stools and
  2. Antibiotic exposure in last 3 months

III. Testing not indicated

  1. Solid stools
    1. Suggests asymptomatic carrier
    2. No benefit to treating carriers
  2. Re-evaluation after treatment
    1. Carriage is common for 3-6 weeks post-treatment

IV. Specimen

  1. Immediate exam of fresh stool specimen
  2. May be kept refrigerated if exam delayed

V. Available tests

  1. Tissue culture Cytotoxicity Assay (Gold Standard)
    1. Test Sensitivity: 67-100%
    2. Test Specificity: 85-100%
    3. Expensive and requires 2 day incubation
  2. Enzyme Immunoassay for Toxins A and B
    1. Test Sensitivity: 63-99% (most are 85-95% sensitive)
    2. Test Specificity: 93-100%
    3. Inexpensive and results available within 2-6 hours
  3. New tests (still in development)
    1. C. difficile combination assay
      1. Glutamate dehydrogenase: 97% sensitivity
      2. Toxins A and B: 97-99% Specificity
  4. Tests not recommended for routine screening
    1. Latex agglutination assay (low accuracy)
    2. C. difficile culture (non-specific)
    3. Toxin A or B PCR (expensive and time intensive)

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Ontology: Clostridium difficile toxin (C0314765)

Concepts Biologically Active Substance (T123) , Hazardous or Poisonous Substance (T131) , Amino Acid, Peptide, or Protein (T116)
SnomedCT 12671002
LNC LP31758-3
English clostridium difficile toxins, clostridium difficile toxin, Clostridium difficile toxin, Clostridium difficile toxin (substance)
Spanish toxina de Clostridium difficile (sustancia), toxina de Clostridium difficile