• Impaired copper excretion causes copper to accumulate in the body.
  • Early-stage Wilson disease is characterized by the presence of copper deposits in the liver.
  • As the disease progresses, copper accumulates in other organs as well, most importantly in the brain and cornea.

Epidemiology


Etiology


Pathophysiology

  • Autosomal recessive mutations in the ATP7B gene (Wilson gene) on chromosome 13, which encodes for a membrane-bound, copper-transporting ATPase → defective ATP7B protein
    • Reduced incorporation of copper into apoceruloplasmin → ↓ serum ceruloplasmin (The major carrier of copper in the blood and an important enzyme with ferroxidase activity.)
    • Reduced biliary copper excretion
  • Results in ↑ free serum copper → accumulation in the liver, cornea, CNS (basal ganglia, brain stem, cerebellum), kidneys, and enterocytes Pasted image 20231029105439.png

Tip

Don’t mess up with Hemochromatosis


Clinical features

Pasted image 20231015091950.png

  • Neurological
    • Cerebellar symptoms, e.g.:
      • Dysarthria (most common)
    • Extrapyramidal symptoms, e.g.:
      • Dystonia
      • Parkinsonism
      • Tremor (usually asymmetric, affecting the hands), which may be any combination of:
        • Resting tremor
        • Intention tremor
        • Wing-beating tremor: a low frequency, high amplitude tremor that is most prominent when the arms are outstretched anteriorly or laterally
    • Drooling (caused by oropharyngeal dysphagia)
    • Cognitive impairment

Wilson disease vs hemochromatosis

  • Wilson disease has neurologic symptoms but hemochromatosis doesn’t have
  • Think about Wilson from Don’t Starve, the mad scientistPasted image 20241030153040.png

Diagnostics


Treatment

General principles

  • Encourage a low-copper diet (e.g., avoidance of organ meats, shellfish, nuts, chocolate, copper-containing dietary supplements).
  • Refer patients with refractory decompensated cirrhosis or acute liver failure for liver transplantation.

Pharmacological therapy

  • First line: chelating agents, e.g., penicillamine (preferred) or trientine
    • Chelating agents facilitate renal excretion of copper by forming water-soluble compounds.
  • Maintenance therapy: reduced-dose zinc salts or a chelating agent