A 22-year-old college student presents to the clinic for evaluation of progressive tremor and declining academic performance. Her family reports increasing irritability and mood changes over the past year. She has no significant medical history. She does not take any medications and does not use any illicit substances. Temperature is 36.7°C (98.1°F), blood pressure is 116/72 mm Hg, pulse is 76/min, and respiratory rate is 14/min. Physical examination reveals a mild resting tremor and dysarthria. Slit-lamp examination demonstrates brownish rings at the corneal margins. Laboratory studies reveal elevated liver enzymes.
Which of the following is the most likely underlying abnormality?
The correct answer is:
A: Copper accumulation due to impaired biliary excretion.
This patient has Wilson disease, characterized by hepatic dysfunction, neuropsychiatric symptoms, movement disorders, and Kayser-Fleischer rings. The disease results from mutations affecting copper transport, leading to impaired biliary copper excretion and progressive copper accumulation in the liver, brain, and other tissues.
Answer choice B: Excessive intestinal iron absorption, is incorrect.
This describes hereditary hemochromatosis rather than Wilson disease.
Answer choice C: Increased alpha-1 antitrypsin production, is incorrect.
Alpha-1 antitrypsin deficiency results from abnormal protein accumulation, not excess production, and does not cause the findings seen in this patient.
Answer choice D: Mitochondrial toxicity from acetaminophen, is incorrect.
Acetaminophen toxicity causes acute liver injury through a toxic metabolite and does not cause a chronic neurologic disease.
Answer choice E: Progressive fibrosis of the extrahepatic bile ducts, is incorrect.
This describes primary sclerosing cholangitis.
Key Learning Point
Wilson disease results from impaired biliary copper excretion and should be suspected in young patients with liver disease, neurologic symptoms, and Kayser-Fleischer rings.
