Related Experiment Video

Updated: Aug 8, 2026

Cefoperazone-treated Mouse Model of Clinically-relevant Clostridium difficile Strain R20291
06:51

Cefoperazone-treated Mouse Model of Clinically-relevant Clostridium difficile Strain R20291

Published on: December 10, 2016

[Pseudomembraneous colitis caused by a toxin B-positive and a toxin A-negative strain of Clostridium difficile]

Lars Jakobsen1, Michael Tvede

  • 1Herning Sygehus, Medicinsk Afdeling, og H:S Rigshospitalet. larsj@dadlnet.dk

Ugeskrift for Laeger
|May 6, 2006
PubMed

Insights

A rare Clostridium difficile (CD) strain causing pseudomembranous colitis (PMC) is undetectable by standard toxin A tests. Consider toxin B-positive strains if CD is suspected but toxin A tests are negative.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Gastroenterology

Background:

  • Pseudomembranous colitis (PMC) is often caused by Clostridium difficile (CD) infection.
  • Standard diagnostic methods in Denmark primarily test for toxin A production using enzyme immunoassays (EIA).

Observation:

  • A case of PMC was caused by a Clostridium difficile strain that was negative for toxin A but positive for toxin B.
  • This specific strain (toxin A- B+) is undetectable by the commonly used toxin A EIA.

Findings:

  • The toxin A-negative, toxin B-positive Clostridium difficile strain poses a diagnostic challenge.
  • Clinical suspicion of CD-associated diarrhea warrants consideration of this strain when toxin A tests are negative.

Implications:

  • Healthcare providers should consider alternative diagnostic tests, such as cellular cytotoxicity assays or combined toxin A/B EIA, for accurate diagnosis.
  • Oral vancomycin remains the standard treatment for severely ill patients with PMC, regardless of the specific toxin profile.

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