Clostridium spp. is a genus belonging to the phylum Firmicutes. While interpreting the literature, careful attention should be paid to the phylogenetic classification of this group due to minor spelling differences between the taxonomic levels. Beyond the phylum level, it is broken down as follows: Class: Clostridia, Order: Clostridiales, Family: Clostridiaceae, and finally, Genus: Clostridium. 

The Clostridium genus contains more than 100 species, most of which are commensal, however it does include pathogens. The literature discusses Clostridial clusters, which may include other species belonging to Eubacterium, Ruminococcus, Roseburia, Butyrivibrio, Faecalibacterium and other genera. These clusters exist due to historic issues with classification, where unclassified species would be moved into the Clostridium category.

Clostridium spp. is part of the intestinal indigenous microbiota and they can produce several endogenous infections.

- Clostridia are one of the most commonly studied anaerobes that cause disease in humans.

- The Clostridium genus contains more than 100 species.

- Clostridia spp are vegetative cells that are rod shaped and arranged in pairs or short chains.

- Clostridium genus bacteria are often described as a biological threat but many of them have positive properties and are used in cosmetic and medicine manufacturing.

- Clostridia typically live in dust, soil, water and in human and animal intestines.

- When the environment is hostile, Clostridia produce spores which are resistant to many disinfectants, including some with antimicrobial properties.

- The odour produced by the Clostridia metabolism can be likened to that of mud, manure and the decay of plant materials.

Clostridium is a genus of bacteria that includes over one hundred distinct species, many of which are abundant and normal inhabitants (commensal) of the human gastrointestinal tract (GIT). Most of the Clostridium species are not virulent and can even have beneficial effects on health and integrity of the GIT in part by breakdown of polysaccharides and fermentation of carbohydrates to short chain fatty acids. However a few species are well-established opportunistic pathogens that produce specific toxins that cause diseases such as food-borne illnesses and, antibiotic-associated diarrhea and pseudomembranous colitis. Some species of Clostridium have been associated with neurological disorders and are the subject of ongoing research. Due to the biodiversity within the Clostridium genus it may be helpful to identify the prevalence of specific Clostridium species that are transiently or permanently present in the GIT of symptomatic patients.

The genus Clostridium includes two serious human pathogens:

1. C.botulinum produces the toxin that causes botulism, which occurs primarily from food poisoning but can also result from wounds or injecting street drugs with infected needles.

2. C.difficile, a normal part of the gut bacteriome, can cause severe diarrhea and abdominal pain when the balance of normal bacteria is impacted. C. difficile is disrupted by taking antibiotics. The elderly or those with Irritable Bowel Syndrome or Colorectal cancer are at a greater risk of developing a C. difficile infection.

References:

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