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Most of the copper in the body is located in the liver, bones, and muscle, but traces of copper occur in all tissues of the body. The liver excretes excess copper into the bile for elimination from the body. Copper is a component of many enzymes, including ones that are necessary for the following:
Wilson's Disease
In Wilson's disease, a rare hereditary disorder, the liver does not excrete excess copper into the bile as it normally does, resulting in accumulation of copper in the liver and liver damage.
Because the liver does not excrete excess copper, copper accumulates in the liver and damages it, causing cirrhosis. The damaged liver releases copper directly into the blood, and copper is carried to other organs, such as the brain, kidneys, and eyes, where it also accumulates.
Symptoms
Symptoms usually begin between ages 6 and 30. In almost half of affected people, the first symptoms result from brain damage. They include tremors, difficulty speaking and swallowing, drooling, incoordination, involuntary jerky movements (chorea), personality changes, and even psychosis (such as schizophrenia or manic-depressive illness). In most of the other people, the first symptoms result from liver damage, which causes hepatitis and eventually cirrhosis.
The cornea of the eyes may contain outer gold or greenish gold rings (Kayser-Fleischer rings) caused by copper that accumulates there. People may have anemia because red blood cells rupture (causing hemolytic anemia). Women may have no menstrual periods or repeated miscarriages.
Diagnosis
Doctors suspect Wilson's disease based on symptoms, such as unexplained hepatitis, tremors, and personality changes. The following tests help confirm the diagnosis:
If children have a family history of the disease, tests are done after about age 1 year. Tests done earlier are likely to miss the disease.
Treatment
Drugs that bind with copper, such as penicillamine, taken by mouth, are used to remove the accumulated copper. People also need to follow a diet that is low in copper. Foods to avoid include beef liver, cashews, black-eyed peas, vegetable juice, shellfish, mushrooms, and cocoa. For the rest of their life, people with Wilson's disease must take penicillamine, another similar drug, or zinc supplements. These drugs help prevent copper from reaccumulating. Without lifelong treatment, Wilson's disease is fatal.
People who do not take the drugs as directed, especially younger people, may develop liver failure. Liver transplantation can cure the disease.
Copper Deficiency
Copper deficiency is rare among healthy people. It occurs most commonly among infants who are premature, who are recovering from severe undernutrition, or who have persistent diarrhea. A severe disorder that impairs absorption of nutrients (such as celiac disease, Crohn's disease, cystic fibrosis, or tropical sprue) or weight-loss (bariatric) surgery may cause this deficiency. Consumption of too much zinc can reduce the absorption of copper, causing a deficiency. Some male infants inherit a genetic abnormality that causes copper deficiency. This disorder is called Menkes syndrome.
Symptoms of copper deficiency include fatigue, anemia, and a decreased number of white blood cells. Sometimes osteoporosis develops or nerves are damaged. Nerve damage can cause tingling and loss of sensation in the feet and hands. Muscles may feel weak. Some people become confused, irritable, and mildly depressed. Coordination is impaired.
Menkes syndrome causes severe mental retardation, vomiting, and diarrhea. The skin lacks pigment, and the hair is sparse, steely, or kinky. Bones may be weak and malformed, and arteries are fragile, sometimes rupturing.
Copper deficiency is usually diagnosed based on symptoms and on blood tests that detect low levels of copper and ceruloplasmin (a copper-carrying protein).
The cause is treated, and a copper supplement is given by mouth. For infants with Menkes syndrome, copper is injected under the skin (subcutaneously).
Copper Excess
Consumption of excess copper is rare. People may consume small amounts of excess copper in acidic food or beverages that have been in copper vessels, tubing, or valves a long time. Consuming even relatively small amounts of copper may cause nausea, vomiting, and diarrhea. Large amounts, usually consumed by people intending to commit suicide, can damage the kidneys, inhibit urine production, and cause anemia due to the rupture of red blood cells (hemolytic anemia) and even death. Rarely, liver damage or cirrhosis occurs in children. It probably results from drinking milk that has been boiled or stored in corroded copper or brass vessels.
Doctors measure copper and ceruloplasmin levels in blood or urine. However, a liver biopsy is usually required for diagnosis unless large amounts of copper were consumed.
If large amounts of copper were consumed, the stomach is pumped, and dimercaprol is injected into a muscle. Then drugs that bind with copper, such as penicillamine, are given to remove excess copper. Occasionally, death occurs despite treatment. Children with liver damage are treated with penicillamine.
Last full review/revision August 2008 by Larry E. Johnson, MD, PhD
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