Which one of the following diseases or conditions predisposes a patient to acetaminophen toxicity?
**Core Concept**
Acetaminophen toxicity occurs when the normal metabolic pathway is overwhelmed, leading to the accumulation of toxic metabolites. The cytochrome P450 enzyme system plays a crucial role in the metabolism of acetaminophen. Certain conditions that affect this enzyme system can increase the risk of acetaminophen toxicity.
**Why the Correct Answer is Right**
Patients with chronic alcohol use disorder (Option C) are at a higher risk of acetaminophen toxicity. This is because chronic alcohol consumption induces the cytochrome P450 enzyme system, increasing the production of the toxic metabolite N-acetyl-p-benzoquinone imine (NAPQI). Additionally, alcoholics may take higher doses of acetaminophen to relieve hangover headaches, further increasing their risk of toxicity.
**Why Each Wrong Option is Incorrect**
* **Option A:** Hepatitis B is a viral infection that can cause liver damage, but it is not directly related to the metabolism of acetaminophen.
* **Option B:** Diabetes mellitus is a metabolic disorder that affects glucose metabolism, but it does not affect the cytochrome P450 enzyme system or the metabolism of acetaminophen.
* **Option D:** Chronic kidney disease may affect the excretion of acetaminophen and its metabolites, but it does not directly increase the risk of acetaminophen toxicity.
**Clinical Pearl / High-Yield Fact**
Chronic alcoholics taking acetaminophen for hangover relief are at a higher risk of acetaminophen toxicity due to increased production of NAPQI and higher doses of acetaminophen.
**Correct Answer: C. Chronic alcohol use disorder.