Toxicology USMLE Step 1 Practice Question
A 42-year-old man presents with severe vomiting and diarrhea 6 hours after consuming foraged wild mushrooms. He initially improves but returns 2 days later with jaundice, abdominal pain, and altered mental status. Vitals show BP 98/62, HR 118, RR 22, temp 37.8°C. Laboratory studies reveal INR 4.2, AST 2,400 U/L, and acute kidney injury. Notably, he denies hemoptysis. Which mechanism best explains the responsible toxin's hepatotoxicity?
Answer choices
- AIrreversible inhibition of acetylcholinesterase
- BActivation of ryanodine receptors
- CBlockade of GABA-A receptors
- DInhibition of RNA polymerase IICorrect answer
- EChelation of ferric iron
- FPhalloidin (actin stabilization)
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