Clostridial Myonecrosis (Gas Gangrene).

Clostridial myositis and myonecrosis, or gas gangrene, is an acute, rapidly progressive, non-pyogenic, invasive clostridial infection of the muscle tissue characterized by profound toxemia, extensive edema, massive death of tissue, and a variable degree of gas production [1-2]. Gas gangrene is either an endogenous infection caused by contamination from a clostridial focus in the body (spontaneous, atraumatic) or an exogenous infection found mostly in patients with compound and/or complicated fractures with extensive soft tissue injuries after trauma (non-spontaneous, traumatic). The onset of gas gangrene may occur between one to six hours after injury or operation and begins with severe and sudden pain in the infected area before the clinical signs appear. In atraumatic clostridial myonecrosis there are certain predisposing risks such as colonic and gynecologic malignancy, radiation, chemotherapy, and neutropenia. Seemingly disproportionate pain in a clinically still-normal area must make the clinician highly suspicious for developing gas gangrene, especially after trauma or operation. In the early phases, the skin overlying the infected area appears shiny and tense. In the next phase it becomes dusky and progresses to a bronze discoloration. The infection can advance very rapidly, and the patient may become moribund within 12 hours [3]. Hemorrhagic bullae or vesicles may be noted. A thin, serosanguinolent exudate with a sickly, sweet odor is present. Swelling and edema of the infected area is pronounced. The muscles appear dark red to black or greenish. They are noncontractile and do not bleed when cut. The tissue gas seen on radiographs appears as featherlike figures between muscle fibers and is an early and highly characteristic sign of clostridial myonecrosis. Crepitus is usually present as well. Systemic toxicity presents as high fever and tachycardia, followed by shock and multiorgan failure [3].