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VOLUME 11 , ISSUE 1 ( January-December, 2021 ) > List of Articles


Virulence Factors Associated with Clostridiodes difficile: An Overview

Chetana Vaishnavi

Keywords : Binary toxin, Clostridiodes difficile infection, Flagella, Spores, Surface layer proteins, Toxin A, Toxin B, Virulence factors

Citation Information : Vaishnavi C. Virulence Factors Associated with Clostridiodes difficile: An Overview. J Gastrointest Infect 2021; 11 (1):24-29.

DOI: 10.5005/jp-journals-10068-3047

License: CC BY-NC 4.0

Published Online: 18-01-2022

Copyright Statement:  Copyright © 2021; The Author(s).


Clostridiodes difficile is a health threat mainly acquired via the feco-oral route and colonizes the human gut. There is a wide range of clinical presentation of C. difficile infection (CDI). C. difficile can be accountable for 15–25% of antibiotic-related diarrhea and up to 100% of pseudo-membranous colitis. Clinically important C. difficile are evolving and increasingly being reported globally. The pathogenesis of C. difficile is associated with many established and potential virulence factors. They include toxins, surface layer proteins, cell wall proteins, flagella, fimbriae, spores, etc. The main virulent factors of CDI are toxin A and toxin B, both of which share a high structural and functional resemblance between them. Both these toxins are responsible for neutrophil infiltration marked by mucosal insult and colitis which is a significant feature of CDI. These toxins also influence the cytoskeletal features, despite the difference in activity potency. A third toxin, produced by some C. difficile strains, contains components of both toxin A and toxin B and is referred to as the binary toxin. The role of this toxin in CDI virulence is not clear. Besides the above described virulence features there are other probable factors that could be involved in C. difficile colonization. They are flagella, surface layer protein, production of tissue degradative exoenzymes, and sporulation. In this overview, the virulence factors associated with C. difficile shall be discussed to highlight their potential role in the disease.

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