Wilson's disease Health Article

Definition

Wilson's disease is an inherited disorder where there is excessive amounts of copper in the body's tissues. This causes a variety of effects, including liver disease and damage to the nervous system.

Alternative Names

Hepatolenticular degeneration

Causes, incidence, and risk factors

Wilson's disease is a rare inherited disorder. If both parents carry an abnormal gene for Wilson's disease, there is a 25% chance in each pregnancy that the child will have the disorder (i.e., it is an autosomal recessive disease).

Wilson's disease causes the body to take in and keep too much copper. The copper deposits in the liver, brain, kidneys, and the eyes. The deposits of copper cause tissue damage, death of the tissues, and scarring, which causes the affected organs to stop working correctly. Liver failure and damage to the central nervous system (brain, spinal cord) are the most predominant, and the most dangerous, effects of the disorder. If not caught and treated early, Wilson's disease is fatal.

It is most common in eastern Europeans, Sicilians, and southern Italians, but may occur in any group. The disorder most commonly appears in people under 40 years old. In children, the symptoms begin to show by around 4 years of age.

Symptoms

• Enlargement of the abdomen (abdominal distention)
• Splenomegaly
• Yellow skin (jaundice) or yellow color of the white of the eye (icterus)
• Vomiting blood
• Weakness
• Tremors of the arms or hands
• Difficulty moving arms and legs, stiffness
• Abnormal arms and legs posture
• Slow movements
• Difficulty walking
• Unpredictable and jerky movement
• Uncontrollable movement
• Weakness of the head, neck, face, or arms
• Speech impairment
• Slow or decreased facial movement and expressions
• Emotional or behavioral changes
• Confusion or delirium
• Dementia (loss of many brain functions)

Signs and tests

An eye examination may show:

• Kayser-Fleischer rings (rusty or brown-colored ring around the iris).
• Eye movement may be restricted.

A physical examination may show signs of:

• Liver or spleen disorders (including cirrhosis and liver necrosis)
• Damage to the central nervous system including loss of coordination, loss of muscle control, muscle tremors, loss of cognitive and intellectual functions, loss of memory, confusion (delirium or dementia), and other damage.

Lab findings may include:

• Serum ceruloplasmin - low (although it is normal in 5% of cases)
• Serum copper - low in spite of the copper deposits in tissues
• Urine copper - high
• CBC - may show hemolytic anemia or decreased white blood cell count
• Serum uric acid levels - low

If there are liver problems, lab abnormalities include:

• PT and PTT - elevated
• AST and ALT - elevated
• Albumin - decreased
• Bilirubin - elevated

Other tests findings may include:

• Head MRI or head CT scan may be abnormal, especially in a region of the brain called the basal ganglia.
• Abdominal x-ray, abdominal MRI, or CT scan of the abdomen may indicate liver disease or other abnormality.
• Liver biopsy or biopsy of the kidneys or other suspect tissue shows deposits of copper, and shows tissue changes that indicate damage to the tissues. This disease may increase the protein and amino acid levels in a 24-hr. urine specimen.

The specific gene responsible for the abnormality that causes Wilson's disease has been identified. It is called ATP7B. However, a simple genetic test to screen for Wilson's disease has not yet been developed. Testing is complicated because there are many possible mutations in this gene.