Salmonellosis (enteric infection): The illness is primarily associated with which Salmonella toxin component during pathogenesis in the host?
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AEnterotoxin of Salmonella spp.
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BEndotoxin of Salmonella spp.
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CNeurotoxin of Salmonella spp.
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DExoenterotoxin of Salmonella spp.
Answer
Correct Answer: Endotoxin of Salmonella spp.
Explanation
Introduction / Context:Salmonellosis is a foodborne infection, not a classic preformed-toxin intoxication. Clinical features include fever, abdominal cramps, and diarrhea after ingestion of live Salmonella that invade and trigger inflammation.
Given Data / Assumptions:
- Focus on the toxin component implicated in disease manifestations.
- Salmonella are gram-negative bacilli with lipopolysaccharide (LPS) endotoxin.
Concept / Approach:Endotoxin (the lipid A component of LPS) contributes to fever and inflammatory responses. While Salmonella may elaborate enterotoxin-like factors, the core, well-known toxic moiety for systemic effects is endotoxin.
Step-by-Step Solution:Classify disease type: infection requiring bacterial invasion.Identify principal toxin: endotoxin intrinsic to Salmonella cell envelope.Select ‘‘Endotoxin of Salmonella spp.’’
Verification / Alternative check:Host response to LPS is central to gram-negative sepsis and to febrile responses in invasive Salmonella infections.
Why Other Options Are Wrong:
- Enterotoxin/exoenterotoxin: less central than endotoxin in typical salmonellosis.
- Neurotoxin: Salmonella do not produce a neurotoxin comparable to botulinum toxin.
Common Pitfalls:Confusing intoxication (preformed toxin) with infection; misattributing neurotoxic mechanisms to Salmonella.
Final Answer:Endotoxin of Salmonella spp.