Clostridium differentiation

Clostridium spp. are part of the Firmicutes phylum, which consists of more than 200 different genera such as Lactobacillus, Bacillus, Clostridium, Enterococcus, and Ruminicoccus. Clostridium genera represent 95% of the Firmicutes phyla. They are obligate anaerobic bacteria, and oxygen is toxic to them. Species of the class Clostridia are often, but not always, gram-positive. Clostridia bacteria are frequently found in the gut biome.

Clostridia are spore-forming, gram-positive, anaerobic (although some species are microaerophilic) microbiota. They are known to produce a variety of toxins, some of which are potentially lethal. There are three types of clostridia that cause widely recognized and often fatal diseases. Clostridium tetani is the etiological agent of tetanus, Clostridium botulinum is the etiological agent of botulism, and Clostridium perfringens is one of the etiological agents of gas gangrene. Tetanus is contracted by contact between spores of C. tetani and an open wound, such as stepping on a rusty nail.

Clostridium difficile
Clostridium difficile, also known as Peptoclostridium difficile, belongs to the gram-positive, spore-forming bacteria. Overuse of antibiotics can lead to an imbalance of the gut biome, resulting in an overgrowth of the species Clostridium difficile and causing a severe infection. Effects of this infection can lead to severe diarrhea, and the increase in severity of many gut-related diseases is also heightened due to the infection. Other Clostridia bacteria in the gut have been linked to brain connectivity and healthy function.

C. difficile is found in nature in water, air, human and animal feces, on most surfaces (especially in hospitals), and particularly in soil. C. difficile exhibits optimal growth at human body temperature (37 ℃). Excessive growth of the bacteria in the intestines of human and animal hosts leads to an accumulation of toxins and their harmful effects. It can be transmitted from person to person via the fecal-oral route, often in hospital settings.

C. difficile is catalase- and superoxide dismutase-negative and produces two types of toxins: enterotoxin A and cytotoxin B, which disrupt cytoskeletal signal transductions in the host. Under stress conditions, the bacteria produce spores that can survive extreme conditions that active bacteria cannot tolerate.

Clostridium difficile infection (CDI) is a symptomatic infection caused by the spore-forming bacterium Clostridium difficile. It is spread by bacterial spores in feces. Surfaces can become contaminated with the spores, and further spread occurs via the hands. Risk factors for infection include antibiotic or proton pump inhibitor use, hospitalization, other health problems, and older age.

Diagnosis is by stool culture or testing for the bacterium's DNA or toxins. If a person tests positive but has no symptoms, the condition is known as C. difficile colonization rather than an infection.

Symptoms of Clostridium difficile infection include watery diarrhea, fever, nausea, and abdominal pain. C. difficile infection can take more severe forms such as persistent diarrhea (at least three loose stools per day), dehydration, severe abdominal pain, loss of appetite, and nausea. It accounts for approximately 20% of cases of antibiotic-associated diarrhea. Complications can include pseudomembranous colitis, toxic megacolon, colon perforation, and sepsis.

Clostridium scindens
Clostridium scindens is capable of converting primary bile acids into toxic secondary bile acids, as well as converting glucocorticoids into androgens by side-chain cleavage. C. scindens can colonize the human large intestine, and its presence is associated with resistance to C. difficile infection, due to the production of secondary bile acids that inhibit the growth of C. difficile.

Clostridium differentiation

Clostridium sporogenes
Clostridium sporogenes is often found in soil and can sometimes colonize the human gastrointestinal tract, but only in a small subgroup of the population.

Clostridium histolyticum
Clostridium histolyticum can occur in soil and is also likely a resident of the intestinal tract in humans and animals.

Clostridium sordellii
Clostridium sordellii is a rare form of Clostridium that can cause pneumonia and arthritis, among other conditions.

Clostridium septicum
Clostridium septicum is found in soil and in the intestinal tract of humans and animals. It is increasingly isolated from human blood, especially in patients with reduced immunity.

Clostridium tetani
Clostridium tetani is widely distributed in soil, but also in the intestinal tract of humans and animals. After autolysis, the bacterium can release the exotoxin tetanospasmin, which can lead to tetanus in humans.

Clostridium bifermentans
Clostridium bifermentans is a very rare human pathogen.

Clostridium baratii
Clostridium baratii can, in very rare cases, cause botulism in newborns, leading to loss of muscle tone and feeding problems due to respiratory difficulties, which can be fatal.