Organism responsible for gas gangrene is/are:
**Core Concept**
Gas gangrene is a severe and potentially life-threatening infection characterized by the rapid production of gas in tissues, typically resulting from the invasion of Clostridium species. This condition is often associated with traumatic injuries, particularly those involving contamination with soil or feces.
**Why the Correct Answer is Right**
The primary organism responsible for gas gangrene is **Clostridium perfringens** (previously known as Clostridium welchii). This anaerobic bacterium produces a range of toxins, including alpha-toxin, which causes tissue destruction and gas production. The alpha-toxin acts by activating phospholipase C, leading to the breakdown of cell membranes and the release of gas in the tissues. The resulting condition is characterized by severe pain, swelling, and gas bubbles in the affected area.
**Why Each Wrong Option is Incorrect**
* **Option A:** Clostridium difficile is primarily associated with antibiotic-associated diarrhea and colitis, not gas gangrene.
* **Option B:** Clostridium tetani is responsible for tetanus, a condition characterized by muscle rigidity and spasms, not gas gangrene.
* **Option D:** Clostridium difficile is not typically associated with gas gangrene.
**Clinical Pearl / High-Yield Fact**
The presence of a foul odor, severe pain, and gas bubbles in a wound can be indicative of gas gangrene, requiring prompt surgical intervention and antibiotic therapy.
**Correct Answer:** C. Clostridium perfringens