Gas gangrene is associated with?

DSSSB - 29 August 2019 (Shift-1)

Applied Microbiology & Infection control

Easy

Appeared in: DSSSB - 29 August 2019 (Shift-1)

Explanation

Gas gangrene (clostridial myonecrosis) is most commonly caused by Clostridium perfringens.
This species is responsible for approximately 60% of all traumatic gas gangrene cases.
The pathogenesis involves the production of powerful exotoxins, particularly alpha-toxin, which is a lecithinase that destroys cell membranes, leading to widespread tissue necrosis and gas production.
Its rapid growth in anaerobic environments (e.g., deep, crushed wounds) contributes to the fulminant nature of the infection.

Option A: While Clostridium novyi can cause gas gangrene, it is a much less common cause compared to C. perfringens. It is considered a secondary or probable agent.
Option B: Clostridium tetani is the causative agent of tetanus, not gas gangrene. The diseases have entirely different mechanisms and clinical presentations.
Option C: Similar to C. novyi, Clostridium histolyticum is a recognized but less common cause of gas gangrene. C. perfringens is the principal pathogen.

Clinical Relevance

Nursing practice connection: Knowing Etiology of Gas Gangrene helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Recognizing the signs of gas gangrene (sudden severe pain, foul-smelling discharge, skin discoloration, and crepitus) is a critical nursing skill for early intervention.
Gas gangrene is a surgical emergency. The nurse's role includes preparing the patient for immediate surgical debridement, administering high-dose IV antibiotics as prescribed (often penicillin and clindamycin), and managing septic shock.
What if? If a patient with a deep, contaminated wound develops fever, tachycardia, and hypotension but lacks significant skin changes or crepitus, the nurse should still suspect a deep soft tissue infection like necrotizing fasciitis or early gas gangrene and escalate concerns immediately, as systemic signs often precede classic local signs.

How to Approach the Question

First, identify the core subject of the question, which is 'gas gangrene'.
This is a factual recall question that tests your knowledge of microbiology.
Recall the common pathogenic bacteria, specifically the Clostridium genus.
Differentiate the diseases caused by the most important Clostridium species: C. perfringens (gas gangrene), C. tetani (tetanus), C. botulinum (botulism), and C. difficile (colitis).
Even though other options like C. novyi and C. histolyticum can cause gas gangrene, select C. perfringens as it is the most common and primary causative agent.

Concept Tested & Keywords

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