Gas gangrene is most commonly associated with which organism?

• A. Clostridium bifermentans
• B. Clostridium perfringens
• C. Clostridium sordellii
• D. Clostridioides difficile

Answer: (B)

Gas gangrene is a clostridial myonecrosis most classically caused by Clostridium perfringens, an anaerobic, spore-forming bacterium. This organism produces powerful toxins, especially alpha toxin (a lecithinase) that damages cell membranes and drives rapid tissue necrosis. In necrotic, poorly perfused tissue, the bacteria ferment sugars and amino acids, generating gas that accumulates in the wound and leads to the characteristic crepitus. This combination of toxin-mediated tissue destruction and gas production explains the rapid, life-threatening course of the infection after contaminated or traumatic wounds. Other organisms listed can cause serious infections, but they are not the typical culprits for gas gangrene: Clostridium sordellii can cause wound-related and toxic syndromes but is less common; Clostridium bifermentans may be involved in wound infections but is not the primary cause; Clostridioides difficile causes antibiotic-associated colitis, not gas gangrene.