Gas gangrene due to Clostridium perfringens is primarily caused by which toxin activity?

• A. Hyaluronidase
• B. Protease
• C. Diphtheria toxin
• D. Alpha toxin (lecithinase)

Answer: (D)

Gas gangrene from Clostridium perfringens is driven mainly by its alpha toxin, which is a phospholipase C (lecithinase). This enzyme enzymatically splits phospholipids in cell membranes, causing cell membrane disruption, rapid muscle cell death (myonecrosis), vascular injury, and tissue necrosis. The resulting damage in anaerobic, contaminated wounds leads to gas production and rapid spread of infection. Other factors like hyaluronidase can help the bacteria spread through tissues, but they don’t cause the decisive tissue destruction and gas formation that the alpha toxin produces. Diphtheria toxin is from a different organism and isn’t involved in gas gangrene.