Which bacterium causes gas gangrene, also called clostridial myonecrosis, most often?

Clostridium perfringens most often causes gas gangrene, also called clostridial myonecrosis.

C. perfringens is an anaerobic, spore-forming bacterium found in soil and in the intestines of humans and animals. When it reaches damaged tissue with poor oxygen supply, it can multiply rapidly and produce toxins that destroy muscle and generate gas.

Gas gangrene is a medical emergency involving severe pain, swelling, tissue death, and sometimes bubbles within affected tissue. Rapid surgical removal of dead tissue and antibiotics are central to treatment.

C. perfringens also causes food poisoning, usually after cooked meat or gravy has been kept at an unsafe temperature. Clostridium septicum can cause myonecrosis too, but C. perfringens is the classic and most common cause.