64-year-old woman with osteoarthritis is brought to the hospital because of a 2-day history of nausea and vomiting. Over the past few weeks, she has been taking acetaminophen frequently for worsening knee pain. Examination shows scleral icterus and tender hepatomegaly. She appears confused. Pupils are normal in size and reactive to light. Neurologic examination shows no abnormalities Laboratory results are as follows: Which of the following is the most likely underlying mechanism of drug toxicity in this patient?

Question

64-year-old woman with osteoarthritis is brought to the hospital because of a 2-day history of nausea and vomiting. Over the past few weeks, she has been taking acetaminophen frequently for worsening knee pain. Examination shows scleral icterus and tender hepatomegaly. She appears confused. Pupils are normal in size and reactive to light.  Neurologic examination shows no abnormalities Laboratory results are as follows:  Which of the following is the most likely underlying mechanism of drug toxicity in this patient?

Quizplus · Accepted Answer

Eductional Objective: Excessive acetaminophen use causes toxicity through its metabolite N-acetyl-p-benzoquinone imine, which disrupts hepatocyte mitochondrial function and induces oxidative injury throughout the liver.  The resulting hepatocellular liver injury markedly elevates aminotransferase, with levels sometimes exceeding 1,000 U/L.

64-Year-Old Woman with Osteoarthritis Is Brought to the Hospital Because