Streptococcal myonecrosis, originally described in the 1940s, resembles subacute clostridial gas gangrene. After an incubation period of 3-4 days, there is swelling, edema, and a purulent exudation from the wound. The infected muscle initially appears pale and soft but as the infection progresses, it becomes bright red and then finally purple and gangrenous. These signs are followed by pain, which rapidly becomes severe.
Gas is present in the infected tissue and the involved muscle becomes gangrenous.
The seropurulent discharge has a sour odor. The management of streptococcal myonecrosis includes surgery, combined with the antibiotic regimen outlined for gas gangrene. Surgery consists of relaxing incisions, extending through the deep fascia and into muscle, that will provide adequate drainage and relieve tension. Care must be taken to extend the excision beyond the area of obvious infection into the neighboring or adjacent viable tissue. The University of Iowa.