Wilson Disease - Causes, Symptoms, and Treatment

Introduction

It is a rare genetic disorder that is characterized by the accumulation of excess copper in various body parts, mainly in the liver, the cornea of the eye, and the brain. Symptoms vary depending upon the organ affected and the age of the individual. Wilson disease is progressive, which means if ignored, it can cause brain dysfunction, hepatic disorders, and death. Treatment is focused on reducing copper to average body concentration with the help of medicines and preventing severe complications.

How Is Wilson Disease Caused?

It is an autosomal recessive trait inherited from parents. An individual inherits genes of different traits equally from both parents. When a person gets both the copies of abnormal features from parents, they develop the recessive genetic disorder. An individual is called a carrier when he inherits one normal gene and one gene for the disease.

Researchers have established that Wilson disease is caused by mutations (changes in gene) of the ATP7B gene, which is responsible for the movement of excess copper from the liver to the intestine and then excreted out.

What Are the Symptoms of Wilson Disease?

Excessive copper accumulation in different organs leads to multiple complications in these organs. Symptoms according to the affected organ are:

Liver:

Dysfunctioning of the liver due to disease begins already by six years of age, but the clinical signs are seen in the teenage or early twenties. Common symptoms observed are,

• Jaundice - Yellowish discoloration of the skin, sclera of the eye, and mucous membrane.

• Swelling of the legs.

• Ascites - Accumulation of fluids in the stomach is known as ascites.

• Esophageal Varices - Abnormal blood vessels are present in the esophagus that can bleed.

• The bruising tendency with prolonged bleeding.

• Fatigue and tiredness.

• Liver Failure - In some cases, there are rapid symptoms of liver disease often associated with anemia which leads to liver damage.

Brain:

Neurologic or brain-related symptoms that appear in Wilson disease are:

• Involuntary muscle movements.

• Dysphagia - Difficulty in swallowing.

• Tremor - Shaking movement of body parts that is rhythmic in nature.

• Dysarthria - Slow and slurred speech, difficult to understand.

• Lack of coordination and sync.

• Spasticity - Tightness of muscles due to prolonged contractions.

• Dystonic Postures - Abnormal repetitive posture.

• Kayser- Fleischer Rings - Rusty- brown deposits in the corner of the eyes.

Female Reproductive System:

• Delayed start of menstruation or even ceased in some cases until Wilson disease is treated. This happens due to disturbances in hormone metabolism in the liver.

• Irregular menstrual cycles, miscarriages, or infertility can also happen.

Other Signs and Symptoms:

• Renal tubular damage and kidney stones.

• Joint and bone issues such as premature arthritis.

• Osteoporosis - Decrease in the density of bone.

• Osteophytes - Bony outgrowths noticed in large joints.

• Constricted spinal and extremity joint spaces.

• Psychological problems such as depression, irritability, and bipolar disorder.

What Are Disorders Related to Wilson Disease?

• Viral Hepatitis: A mild liver disease caused due to viral infection.

• Parkinson’s Disease: It is a neural disorder affecting movements. Symptoms of tremor in Wilson disease can be confused with Parkinson's disease.

• Sydenham Chorea: An acute disorder that is self-limiting in nature. It occurs in some cases of rheumatic fever. Symptoms like involuntary muscle movements and clumsiness can resemble Wilson's disease.

• Liver Cirrhosis: Degeneration of liver cells and inflammation due to alcohol.

• Primary Biliary Cholangitis: It is a chronic disease of the liver which includes generalized itching, dark urine, jaundice, and eventually accumulation of excessive copper in the liver.

• Heavy Metal Poisoning: Caused due to individual exposure to toxins such as copper, aluminum, arsenic, or mercury. It can affect the lungs, nervous system, digestive system, and skin.

• Huntington’s Disease: Inherited, progressively degenerative neurological disorder. The initial symptoms are speech and memory impairment and involuntary movement of muscles.

What Are the Diagnostic Procedures for Wilson Disease?

• Slit-Lamp Examination of Eyes: It helps to reveal the presence of Kayser-Fleischer rings.

• Blood Serum Test: To investigate a copper protein in the blood.

• Urine Test: To evaluate the high concentration of copper in the urine.

• Haplotype Analysis: It helps establish whether a person has Wilson disease or is a carrier of the Wilson disease gene.

What Is the Treatment of Wilson Disease?

Wilson disease needs a lifelong aimed treatment for lowering copper levels to normal, non-toxic, and preventing the progression of symptoms.

There are the following types of medications to treat Wilson's disease:

• Chelating agents help to remove copper from the body via urinary excretion. These are, penicillamine (Cuprimine) and Syprine (trientine dihydrochloride).

• Zinc salts are administered to prevent the gut from absorbing copper from the diet.

• Tetrathiomolybdate: It helps to bind up to toxic copper in the blood, making it non-toxic. It also prevents the absorption of copper.

In Cases of Liver Failure:

• Mild to moderate liver failure can be treated by a combination of trientine (Syprine) and zinc for a duration of 4 to 6 months, followed by maintenance therapy with any one of the two.

• Penicillamine and zinc can also be used, but penicillamine has more side effects than zinc.

• In cases of severe liver failure, transplantation is the only treatment of choice.

How to Monitor Wilson Disease?

• Regular follow-ups for a physical examination to evaluate symptoms.

• Copper and zinc (for those on zinc therapy) measurement in 24-hour urine collection.

• Blood tests to check on the amount of free copper (not bound to ceruloplasmin).

• Regular check on liver functioning and copper concentration.

Conclusion:

Wilson disease is a rare genetic disorder inherited from the parents. The disease is characterized by excessive accumulation of copper in different tissues and organs of the body. It is a severe condition if left untreated, it can affect vital organs. However, proper treatment and prophylaxis for a lifetime can help to control the concentration of copper and reverse the symptoms.