Gas gangrene is one of the most fatal infections. It has a mortality rate of 25% and can be 100% in patients with spontaneous gas gangrene or those with delayed treatment. Gas gangrene is caused by a bacterium called Clostridium perfingens. The bacteria is a gram positive, rod shaped, obligate anaerobe, endo-spore forming, toxin producing prokaryotic cell. It is found in soil, sand, dust, and humans. The Clostridium perfingens are the only anaerobic spore-forming genus found in humans. The bacteria have been found in mucous membranes, the GI tract, and female genital tract.
Gas gangrene is rare only 1,000 to 3,000 cases annually in the U.S. It is seen in patients in the age ranges of 15 to 25 and 60 to 70 years of age. The bacteria enter the body through deep tissue or parenteral route. Gas gangrene can be classified as posttraumatic, postoperative, or spontaneous. Posttraumatic gas gangrene accounts for 60% of the cases and most of them involve automobile accidents. With posttraumatic gas gangrene, the patients have sustained serious injury to the skin or soft tissues. The causes of these injuries are crush injuries, compound fractures, gunshot wounds, thermal or electrical burn and frostbite; especially farm or industrial injuries in which the patient's injury is contaminated with soil. Postoperative gas gangrene is usually associated with colon resection, ruptured appendix, bowel perforation, and biliary or other GI surgery. Also, illegal or self-induced abortions are the leading cause of uterine gas gangrene. Spontaneous gas gangrene occurs without external wound or injury. One-third of all gas gangrene cases occur spontaneously. Spontaneous gas gangrene usually occur in patients with underlying conditions such as, colorectal adenocarinoma (highest risk factor), vascular disease, diabetes, or colon cancer.
COURSE OF THE DISEASE
The initial stage of infection is established when the patient is contaminated with clostridal spores. The onset of gas gangrene usually begins suddenly and rapidly worsens. The reason for the rapid onset of this disease is because of its short incubation period of about 24 hours. The symptoms first start with localized pain with edema. Inflammation begins at the site of infection as a pale to brownish red and extremely painful tissue swelling. Gas may be felt in the tissues as a bubbling sensation when the area is pressed on. The microorganisms growing cause the gas because they ferment the carbohydrates in the tissues and produce gases (CO2 and H) that swell the tissue. The pain increases in severity but spreads only as the infection spreads. There can be a feeling of heaviness in the affected extremity. The patient will have blisters filled with a brown red fluid and the drainage from these blisters will be foul smelling. A yellow skin color may develop due to the excessive breakdown of blood cells; this will also cause hemoglobin levels to drop to very low levels. When...