C .perfringens DISEASE
C. perfringens produces a wide range of wound and soft tissue infections, many of which are no different from those caused by other opportunistic bacteria. The most dreaded of these, gas gangrene, begins as a wound infection but progresses to shock and death in a matter of hours. Another form of C. perfringens –caused disease, food poisoning, is characterized by diarrhea without fever or vomiting.
Gas gangrene develops in traumatic wounds with muscle damage when they are contami-nated with dirt, clothing, or other foreign material containing C. perfringens or another species of histotoxic clostridia. The clostridia can come from the patient’s own intestinal ora or spores in the en vironment. Compound fractures, bullet wounds, or the kind of trauma seen in wartime are prototypes for this infection. A signi cant delay between the injury and definitive surgical management is an additional requirement. These conditions are more likely to occur in peacetime in a hiking accident in a remote area rather than in an automobile accident on a freeway.
C. perfringens can cause food poisoning if large numbers of an enterotoxin-producingstrain are ingested. Outbreaks usually involve meat dishes such as stews, soups, or gravies. Clostridial food poisoning is one of the most common food-borne illnesses in de-veloped countries.
If the oxidation – reduction potential in a wound is sufficiently low, C. perfringens spores can germinate and can multiply, elaborating α-Toxin. The process passes along the muscle bundles, producing rapidly spreading edema and necrosis as well as conditions that are more favorable for growth of the bacteria. Very few leukocytes are present in the myo-necrotic tissue. As the disease progresses, increased vascular permeability and systemic absorption of the toxin and inflammatory mediators leads to shock. q-toxin and oxygen deprivation due to the metabolic activities of C. perfringens are probable contributors. The basis for the profound systemic effects is not known, but toxin absorption seems probable, because fatal cases occur without bacteremia.
The spores of some C. perfringens strains are often particularly heat resistant and can withstand temperatures of 100°C for an hour or more. Thus, spores that survive initial cooking can convert to the vegetative form and multiply if food is not refrigerated or is rewarmed. After ingestion, the enterotoxin is released into the upper gastrointestinal tract, causing a fluid outpouring in which the ileum is most severely involved.
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