Which clostridial species is most frequently isolated from cases of gas gangrene? ______________?
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Answer: B. Clostridium welchii
Explanation
Clostridium perfringens produces potent tissue-destroying exotoxins that drive the rapid pathology of gas gangrene. This anaerobic spore-forming bacterium is historically known as Clostridium welchii and is isolated from wounds. Rapid fermentation of muscle carbohydrates produces characteristic gas pockets within infected necrotic tissue areas. Clostridium species are Gram-positive bacilli that form resilient endospores ubiquitous in surface soils. C. perfringens produces alpha-toxin which exhibits phospholipase activity that destroys host cell membranes. Myonecrosis involves extensive muscle destruction accompanied by severe systemic toxicity and high mortality.
Surgical debridement and prompt administration of appropriate antibiotics are essential for managing gas gangrene. Traumatic injuries contaminated with soil carry a high risk of developing severe clostridial soft tissue infections. Hyperbaric oxygen therapy is occasionally used as an adjunctive treatment to inhibit anaerobic bacterial proliferation. Clostridium botulinum produces a potent neurotoxin that causes flaccid paralysis rather than traumatic gas gangrene. Clostridium tetani produces tetanospasmin which causes spastic muscle paralysis rather than local tissue gas production. Clostridium difficile is an enteric pathogen primarily responsible for antibiotic-associated pseudomembranous colitis.
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