A 37-year-old man presents with vomiting, watery diarrhea, and confusion 6 hours after ingesting contaminated herbal supplements. Vital signs show BP 102/68, HR 108, RR 20, temp 37.2°C. He has characteristic garlic odor on breath and denies recent medication use. ECG demonstrates prolonged QT interval. Serum arsenic level is markedly elevated at 45 μg/L (normal <15). Which cofactor is most directly inhibited by this toxin?
- A)Tetrahydrobiopterin
- B)Pyridoxal phosphate
- C)Cobalamin
- D)Lipoic acidGABARITO
- E)Biotin
Explicação
Arsenic inhibits lipoic acid dependent enzyme complexes, especially pyruvate dehydrogenase and alpha ketoglutarate dehydrogenase. This impairs aerobic metabolism and can produce severe gastrointestinal symptoms, neurologic changes, and cardiovascular instabili... Ver explicação completa e trilha adaptativa →