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Gas gangrene usually begins 1 to 4 days after the injury but may start within 10 hours. The earliest reported finding is severe pain at the site of the wound accompanied by a sense of heaviness or pressure. The disease then progresses rapidly with edema, tender-ness, and pallor, which is followed by discoloration and hemorrhagic bullae. The gas is apparent as crepitance in the tissue, but this is a late sign. Systemic findings are those of shock with intravascular hemolysis, hypotension, and renal failure leading to coma and death. Patients are often remarkably alert until the terminal stages.
Anaerobic cellulitis is a clostridial infection of wounds and surrounding subcutaneous tis-sue in which there is marked gas formation (more than in gas gangrene) but in which the pain, swelling, and toxicity of gas gangrene are absent. This condition is much less seri-ous than gas gangrene and can be controlled with less rigorous methods.
If C. perfringens gains access to necrotic products of conception retained in the uterus, it may multiply and infect the endometrium. Necrosis of uterine tissue and septicemia with massive intravascular hemolysis due to a-toxin may then follow. Clostridial uterine infection occurred more commonly in the past, usually after an incomplete illegal abor-tion with inadequately sterilized instruments.
The incubation period of 8 to 24 hours is followed by nausea, abdominal pain, and diarrhea. There is no fever, and vomiting is rare. Spontaneous recovery usually occurs within 24 hours.
Diagnosis is based ultimately on clinical observations. Bacteriologic studies are adjunc-tive. It is quite common, for example, to isolate C. perfringens from contaminated wounds of patients who have no evidence of clostridial disease. The organism can also be isolated from the postpartum uterine cervix of healthy women or from those with only mild fever. Occasionally, C. perfringens is even isolated from blood cultures of patients who do not develop serious clostridial infection. In clostridial food poisoning, isolation of more than 105C. perfringens per gram of ingested food in the absence of any other cause is usually sufficient to confirm the etiology of a characteristic food poisoning outbreak.
Treatment of gas gangrene and endometritis must be initiated immediately because these conditions are almost always fatal if untreated. Excision of all devitalized tissue is of paramount importance, because it denies the organism the anaerobic conditions required for further multiplication and toxin production. This often entails wide resection of mus-cle groups, hysterectomy, and even amputation of limbs. Administration of massive doses of penicillin is an important adjunctive procedure. Because nonclostridial anaerobes and members of the Enterobacteriaceae frequently contaminate injury sites, clindamycin and broad-spectrum cephalosporins are often added to the antibiotic regimen. Placement of patients in a hyperbaric oxygen chamber, which increases the tissue level of dissolved oxygen, has been shown to slow the spread of disease, probably by inhibiting bacterial growth and toxin production and by neutralizing the activity of q-toxin.
The most effective method for prevention of gas gangrene is the surgical debridement of traumatic injuries as soon as possible. Thorough cleansing, removal of dead tissue and foreign bodies, and drainage of hematoma limit organism multiplication and toxin pro-duction. Antimicrobic prophylaxis is indicated but cannot replace surgical debridement, because the antimicrobics may fail to reach the organism in devascularized tissues.
Prevention involves good cooking hygiene and adequate refrigeration. There is grow-ing evidence that enterotoxin-producing strains of C. perfringens may also be responsible for some cases of antimicrobic-induced diarrhea in a setting similar to C. dif cile .
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