AST Surgical Technologist Practice Exam

Which organism is responsible for causing gas gangrene?

1. Staphylococcus aureus

2. Clostridium perfringens

3. Escherichia coli

4. Streptococcus pneumoniae

The correct answer is: Clostridium perfringens

Gas gangrene is caused by the bacterium Clostridium perfringens, which is an anaerobic, spore-forming gram-positive bacillus. This organism is commonly found in soil, decaying vegetation, and the intestines of humans and animals. When Clostridium perfringens invades tissue, often following a deep wound or injury where oxygen levels are low, it can multiply rapidly, producing toxins and gases that lead to the rapid destruction of tissues, hence the name "gas gangrene." The disease typically manifests with severe pain, swelling, and the presence of gas in tissues, leading to the characteristic foul-smelling discharge. Immediate surgical intervention and, in some cases, antibiotic treatment are crucial in managing this infection. Other options provided are associated with different types of infections. For example, Staphylococcus aureus is linked to skin infections and abscesses, Escherichia coli is often responsible for gastrointestinal infections or urinary tract infections, and Streptococcus pneumoniae is primarily known for causing pneumonia and other respiratory infections. None of these organisms are associated with the specific pathology of gas gangrene like Clostridium perfringens.