Clostridioides difficile infection (CDI) & Dysbiosis

Clostridioides difficile infection (CDI) (recurrent) is caused by persistent disruptions of the gut microbiome, typically characterized by reduced proportions of the bacterial phyla Bacillota, Bacteroidota, and Actinomycetota, and an increased proportion of the phylum Pseudomonadota.
Okhuysen et al. 2024 Clin Infect Dis 78: 1462-72

The diversity of the fecal microbiome is reduced in cases of recurrent Clostridium difficile-associated diarrhea.
Chang et al. 2008 J Infect Dis 197: 435-8

References:
Weingarden et al. 2013 J Clin Gastroenterol 47: 735–37
Weingarden et al. 2014 Am J Physiol Gastrointest Liver Physiol 306: G310–19

These changes in the gut microbiome lead to the loss of colonization resistance, as important bacteria essential for the metabolism of bile acids are eliminated, resulting in increased primary bile acid levels that facilitate the germination of C. difficile spores and the onset or recurrence of C. difficile infections.
Buffie & Pamer 2013

see also:
Antibiotics & Clostridioides difficile infection (CDI) (recurrent)
Bacteroidaceae & Clostridioides difficile infection (CDI)
Clostridioides (Clostridium) difficile & Inflammatory Bowel Disease (IBD)
Clostridioides difficile infection (CDI) & Gut microbiota