Clostridioides (Clostridium) difficile in pigs

Characterization, epidemiological considerations and antimicrobial resistance

Abstract

The aim of this review is to synthesize, gather and summarize some aspects related to Clostridioides difficile and its role as a microbiota and pathogen in pigs. C. difficile is an anaerobic, sporulated bacterium and one of the main etiological agents of diarrhea associated with the use of antibiotics. The main virulence factors are two toxins (A and B) that cause damage to the colon epithelium when a dysbiosis occurs, usually it is caused for the antibiotics. It has been determined that this bacterium has a high prevalence in pigs, mainly in the first months of the animal's life and also many of these animals colonized with non-toxigenic strains of C. difficile. However, there are reports of gastroenteritis caused by this bacterium and possibly related to the use and abuse of antibiotics, although the causes of these infections in swine are not yet completely clear and require further investigation. The RT028 is one of the most frequently isolated C. difficile genotypes in pigs, which has also been reported causing epidemic outbreaks in human hospitals; therefore a possible zoonosis has been postulated, although this hypothesis has not been fully demonstrated. Additionally, a high antimicrobial resistance of C. difficile isolates from pigs and multi-resistant phenotypes has been reported, thus this bacterium could be functioning as an ecological reservoir of antimicrobial resistance genes. Finally, it is necessary to establish measures for the rational use of antibiotics in pig farms and a surveillance system on circulating genotypes and resistance of C. difficile in pigs.