What is the clinical utility of Nagler’s reaction in laboratory diagnosis? ______________?
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Answer: C. Gas gangrene
Explanation
Nagler’s reaction identifies lecithinase activity produced by Clostridium perfringens bacteria. Clostridium perfringens is the primary bacterial causative agent responsible for gas gangrene. Option C correctly connects Nagler’s reaction to the laboratory diagnosis of gas gangrene. Lecithinase enzymes split egg yolk lecithin, producing an opaque halo on agar plates. Neutralizing antitoxins added to one half of the plate inhibit this specific enzymatic reaction. Clostridium species produce potent exotoxins causing extensive tissue necrosis and gas production.
Rapid laboratory identification of gas gangrene agents is crucial for emergency surgical debridement. Traumatic wound infections require prompt microbiological screening for clostridial pathogens. Antitoxin administration complements surgical intervention in severe anaerobic wound infections. Malaria is diagnosed by microscopic blood smear examination rather than clostridial Nagler reactions. Whooping cough is caused by Bordetella pertussis, an organism diagnosed using specialized culture media. Woolsorter's disease is caused by Bacillus anthracis which produces different diagnostic reactions.
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