Gas gangrene

Gas gangrene is also called Clostridium perfringens wound infection and Clostridial myonecrosis. The incubation period after trauma is at least 6 hours and usually less than 4 days. It causes excruciating pain at the wound site with increasing edema and foul-smelling drainage and gas bubbles.

CASES/YEAR
1,500 (US); 30,000 (Global)
CATEGORY
Localized Infections
AGENT TYPE
Bacteria
OTHER NAMES
Clostridial myonecrosis; Clostridium perfringens wound infection
ACUITY
Acute-Severe
INCUBATION
After trauma, at least 6 hours and usually less than 4 days; [Harrison ID, p. 463]
INITIAL SYMPTOMS
Excruciating pain at wound site with increasing edema and foul-smelling drainage and gas bubbles; Skin color varies from pale to red or bronze with bullae; Rapid development of fever, shock, hemolysis, and renal failure; [Merck Manual, p. 1469]
PRECAUTIONS
Standard; "Transmission from person to person rare; one outbreak in a surgical setting reported. Use Contact Precautions if wound drainage is extensive." [CDC 2007 Guideline for Isolation Precautions]
COMMENTS
"The margins between healthy and necrotic tissue often advances several inches per hour despite appropriate antibiotic therapy, and radical amputation remains the single best life-saving intervention." [Harrison ID, p. 463] The presence of clostridia in a wound culture is more likely to be significant when the Gram stain shows them in large numbers. "Bacteremia, sometimes with overt hemolysis, occurs in about 15% of patients with traumatic gas gangrene. . . When clinical signs of clostridial infection (e.g., gas, myonecrosis) are present, rapid, aggressive intervention is mandatory. Thorough drainage and debridement are as important as antibiotics; both should be instituted rapidly." [Merck Manual, p. 1295-6] The alpha-toxin produced by C. perfringens can cause hemolytic anemia in cases of severe sepsis. [PPID, p. 2965] Shock is present in 50% of patients at the time of hospital admission. [Cohen, p. 100] Common complications are jaundice, shock, hepatic necrosis, and renal failure. The mortality rate after trauma is about 25% in tertiary centers. Examination of muscle shows putrid discharge, bullae, and crepitation. Gram stain shows many gram-positive rods and no inflammatory cells. [Cecil, p. 1893] "In gas gangrene, the appearance of the involved muscles is characteristic and quite unlike that of any other surgical infection." Spontaneous (nontraumatic) myonecrosis is often associated with colon cancer. [ID, p. 832] See "Necrotizing fasciitis."
DIAGNOSTIC
Clinical; Gram-positive "box-car" on Gram stain; Culture of blood, muscle, and bullae; <1% of blood and wound cultures yielding Clostridia spp. represent gas gangrene. X-ray: gas in tissues; CT scan: myonecrosis; [ABX Guide]
SCOPE
Global
SIGNS & SYMPTOMS
  • >fever
  • G jaundice
  • G liver function test, abnormal
  • H anemia
  • H hemolysis
  • H leukocytosis
  • S skin blister or vesicles
  • *acute renal failure
  • *myocarditis
  • *sepsis
  • *shock
  • *stupor, coma
ANTIMICROBIC

Yes

VACCINE

No

ENTRY
Skin or Mucous Membranes (Includes Conjunctiva)
SOURCE
Soil or Dust (Ingesting or Inhaling)
RESERVOIR
RISK FACTORS
TREATMENT
Usefulness of hyperbaric oxygen is controversial. Surgical consultation needed immediately; [ABX Guide]
DRUG LINK
Merck Manual: Clostridial Soft-Tissue Infections
REFERENCES FOR CASES/YEAR
1. (US) One to three thousand cases in US every year: [Gorbach, p. 190] Calculate average = 1500;
2. (Global) 20 X US cases/yr;