Clostridia are bacteria that commonly reside in the intestine of healthy adults and newborns. Clostridia also reside in animals, soil, and decaying vegetation.
These bacteria produce spores. Spores are an inactive (dormant) form of bacteria. Spores enable bacteria to survive when environmental conditions are difficult. When conditions are favorable, each spore germinates into an active bacterium and produces toxins. The toxins multiply and can affect various parts of the body such as the muscles, digestive tract, and tissues.
These bacteria do not require oxygen to live. That is, they are anaerobes.
There are many different species of clostridia.
Clostridia enter the body in different ways and cause various illnesses depending on the species:
Clostridium botulinum may produce a toxin in food that is then consumed and causes foodborne botulism, or may enter the body through a wound and produce toxins that cause wound botulism.
Clostridium perfringens may be consumed in food and produce a toxin in the intestines that causes Clostridium perfringens food poisoning.
Clostridium tetani may enter the body through a wound and produce a toxin that causes tetanus.
Clostridioides difficile, which may already be present in the large intestine, may overgrow after use of antibiotics and produce toxins that cause antibiotic-associated Clostridioides difficile –induced colitis.
Various species of clostridia may enter through a wound and produce a toxin that destroys tissue and causes gas gangrene.
Various species of clostridia are part of the normal bacterial flora in the colon and vagina. However, in addition to the large intestine, they can cause infection of the gallbladder and female reproductive organs. Clostridium perfringens is most commonly implicated. Rarely, one species, Clostridium sordelli, causes toxic shock syndrome in women who have infection of the reproductive organs.
Clostridium perfringens food poisoning
Clostridium perfringens food poisoning (a type of gastroenteritis) can develop when people eat food (usually beef) that contains clostridia. Clostridia develop from spores, which can survive the heat of cooking. If food that contains spores is not eaten soon after it is cooked, the spores develop into active clostridia bacteria, which then multiply in the food. If the food is served without adequate reheating, the clostridia are consumed. They multiply in the small intestine and produce a toxin that causes watery diarrhea and abdominal cramping.
Clostridium perfringens food poisoning is usually mild and resolves within 24 hours. Rarely, it is severe, particularly in the very young and in older adults.
A doctor usually suspects the diagnosis of Clostridium perfringens food poisoning when a local outbreak of the disease has occurred. The diagnosis is confirmed by testing contaminated food or stool samples from infected people for Clostridium perfringens and its toxin.
To prevent food poisoning, people should promptly refrigerate leftover cooked meat and reheat it thoroughly before serving.
Treatment of Clostridium perfringens food poisoning includes drinking lots of fluids and resting. Antibiotics are not used.
Clostridial abdominal and pelvic infections
Clostridia bacteria, usually Clostridium perfringens, are often involved in abdominal infections, usually with other bacteria (called mixed anaerobic infections).
Clostridia bacteria can infect the intestine, the gallbladder, and organs in the pelvis, such as the uterus, fallopian tubes, and ovaries. Clostridia usually infect the uterus after delivery of a baby or after an abortion done in conditions that are not sterile.
Clostridial infections of the abdomen and pelvis are serious and sometimes fatal. Clostridia produce large amounts of gas, which can form bubbles and blisters in the infected tissue. Often, the infection blocks small blood vessels, and the infected tissue dies, leading to gas gangrene.
Symptoms include pain and fever. The abdomen is tender to the touch. If the uterus is infected, women may have a foul-smelling, bloody discharge from the vagina. Symptoms can progress to a life-threatening complication called sepsis.
To diagnose clostridial abdominal and pelvic infections, doctors take samples of blood or infected tissue. These samples are examined and sent to a laboratory where bacteria, if present, can be grown (cultured) and identified. Doctors may take x-rays to check for gas produced by clostridia.
Clostridial necrotizing enteritis, neutropenic enterocolitis, and neonatal necrotizing enterocolitis
Clostridial necrotizing enteritis is also called enteritis necroticans or pigbel. This infection is caused by Clostridium perfringens and typically affects the small intestine (primarily the jejunum).
The infection ranges from mild to severe and can be fatal if not treated promptly. This rare infection occurs mostly in places where people consume low-protein diets, such as in the hinterlands of New Guinea and parts of Africa, Central and South America, and Asia.
Symptoms vary from mild diarrhea to severe abdominal pain, vomiting, bloody stool, septic shock, and sometimes death within 24 hours.
Diagnosis of clostridial necrotizing enteritis is based on symptoms and stool tests.
Treatment of clostridial necrotizing enteritis is with antibiotics. People who have very severe infections may need surgery.
Neutropenic enterocolitis (typhlitis) is a similar life-threatening infection that develops in the beginning of the large intestine (cecum) of people who have a low white blood cell count (for example, people who have leukemia or are receiving chemotherapy for cancer).
People have fever, abdominal pain, bleeding in the digestive tract, and diarrhea.
The diagnosis is based on symptoms, the white blood cell count, imaging tests of the abdomen, and blood and stool tests.
Treatment is with antibiotics and sometimes surgery.
Neonatal necrotizing enterocolitis occurs mostly in premature newborns who weigh less than about 1500 grams (3 pounds). It may be caused by clostridia bacteria.
Clostridia in the bloodstream
Clostridia bacteria may also spread to the blood and cause bacteremia. Bacteremia can trigger a widespread reaction called sepsis. Sepsis can cause fever and serious symptoms such as low blood pressure, jaundice, and anemia. Sepsis can be rapidly fatal.
To confirm sepsis caused by clostridia, doctors take samples of blood. These samples are sent to a laboratory where bacteria, if present, can be grown (cultured) and identified.
People who have sepsis are admitted to the hospital and are given antibiotics. (See also treatment of sepsis.)
