Gas gangrene is a type of wet gangrene resulting from clostridial infection, especially Clostridium perfringens (welchii).

Clostridia are anaerobic organisms that can survive and multiply only in tissues where there is a low oxygen tension.

The usual site for infection is a dirty wound which has been closed without adequate debridement. The toxins produced by these organisms destroy the cell wall and rapidly lead to tissue necrosis, thus producing disease spread.

Other Clostridia can cause gas gangrene. These include Clostrium novyi and Clostidium septicum.