Causative organism for gas gangrene is :

IGNOU PB. Bsc. Nsg. Entrance-2025

Applied Microbiology & Infection control

Easy

Appeared in: IGNOU PB. Bsc. Nsg. Entrance-2025

Explanation

Clostridium perfringens is the primary bacterial species responsible for causing gas gangrene, also known as clostridial myonecrosis.
This anaerobic, spore-forming bacterium thrives in deep, contaminated wounds with devitalized tissue, which provides the necessary low-oxygen environment.
The bacterium produces potent exotoxins, most notably alpha-toxin (a lecithinase), which causes extensive tissue destruction (myonecrosis), hemolysis, and vascular injury.
The metabolic activity of C. perfringens in the necrotic tissue produces gas, leading to the characteristic clinical sign of crepitus (a crackling feeling under the skin).

Option A: This organism produces the botulinum neurotoxin, which blocks acetylcholine release at the neuromuscular junction, causing botulism—a severe illness characterized by flaccid paralysis.
Option C: This bacterium produces the neurotoxin tetanospasmin, which blocks inhibitory neurotransmitters, leading to tetanus ('lockjaw'), a condition of severe, spastic muscle contractions.
Option D: This species is known for causing gastrointestinal disease, primarily antibiotic-associated diarrhea and pseudomembranous colitis, by producing enterotoxins that damage the lining of the colon.

Clinical Relevance

Nursing practice connection: Knowing Microbiology: Causative agent 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 (severe pain out of proportion to injury, crepitus, foul-smelling discharge) is a critical nursing skill, as it is a surgical emergency requiring immediate intervention to prevent sepsis, shock, and death.
Nursing care involves preparing the patient for emergency surgical debridement, administering high-dose IV antibiotics (like penicillin and clindamycin), managing pain, and potentially arranging for hyperbaric oxygen therapy.
What if? If a patient with a deep, contaminated wound develops severe pain and swelling but no crepitus is palpable yet, the nurse should still have a high index of suspicion for gas gangrene. Crepitus can be a late sign, and early surgical consultation is life-saving.

How to Approach the Question

First, identify the core of the question: it asks for the specific causative agent of 'gas gangrene'.
Next, scan the options. Notice that all options belong to the genus Clostridium, indicating the question is testing your ability to differentiate between the diseases caused by these related bacteria.
Recall or deduce the primary disease associated with each option. Associate C. botulinum with botulism, C. tetani with tetanus, and C. difficile with colitis.
By elimination, or by direct recall, identify C. perfringens as the classic cause of gas gangrene (myonecrosis).
Confirm your answer by remembering that the 'gas' in gas gangrene is produced by the fermentative metabolism of C. perfringens in necrotic tissue.

Concept Tested & Keywords

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