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Cefoperazone-treated Mouse Model of Clinically-relevant Clostridium difficile Strain R20291
Published on: December 10, 2016
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Clostridium difficile binary toxin CDT: mechanism, epidemiology, and potential clinical importance
Dale N Gerding1, Stuart Johnson1, Maja Rupnik2
1Loyola University Chicago Stritch School of Medicine; Hines Veterans Affairs Hospital; Hines, IL USA.
Gut Microbes
|November 21, 2013
Summary
Binary toxin (CDT) in Clostridium difficile strains correlates with more severe C. difficile infection (CDI) and higher mortality. Further research is needed to understand CDT
Area of Science:
- Microbiology
- Toxicology
- Infectious Diseases
Background:
- Clostridium difficile infection (CDI) severity is often linked to the presence of binary toxin (CDT).
- CDT is an ADP-ribosylating toxin composed of CDTa (enzymatic component) and CDTb (binding/translocation component).
- CDT disrupts the host cell actin cytoskeleton, leading to cellular changes and increased bacterial adherence.
Purpose of the Study:
- To investigate the association between binary toxin genes in C. difficile and CDI severity and mortality.
- To highlight the need for further research into CDT's role in CDI pathogenesis and clinical outcomes.
Main Methods:
- Review of clinical studies associating binary toxin genes with CDI outcomes.
- Analysis of the known mechanisms of binary toxin action on host cells.
Main Results:
- Presence of binary toxin genes in C. difficile is associated with increased 30-day CDI mortality, irrespective of PCR ribotype.
- CDT-induced actin depolymerization promotes microtubule-based membrane protrusions, enhancing bacterial adherence.
Conclusions:
- Binary toxin is a significant factor in C. difficile virulence and patient mortality.
- Further studies are required to quantify CDT in stool, analyze mortality from CDT-producing strains, and correlate CDT expression with other toxin variants and ribotypes.
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