Copper

Category:

Copper, Serum

Description 

Copper testing is primarily ordered to help diagnose Wilson's disease. If a doctor suspects Wilson's, then he would typically order a total and/or free (unbound) blood copper test and a ceruloplasmin level test. If these tests are abnormal, then they may be followed by a 24-hour urine copper test to measure copper excretion and a hepatic (liver) copper test to evaluate copper storage.

Genetic testing may also be performed to detect mutations in the ATP7B gene if Wilson's disease is suspected.

If a doctor suspects copper toxicity, copper deficiency, or a disorder that is inhibiting copper metabolism, then he may order blood and/or urine copper tests along with ceruloplasmin. One or more copper tests may be ordered to monitor the effectiveness of treatment for Wilson's disease, copper excess, or copper deficiency.

Its concentration is measured by means of analysis of a blood sample drawn from the vein in the arm.

Purpose of the test

One or more copper tests are ordered along with ceruloplasmin when someone has signs and symptoms of Wilson's disease, excess copper storage, copper poisoning, or due to a copper deficiency. These may include:

-        anemia

-        nausea, abdominal pain

-        jaundice

-        fatigue

-        behavioral changes

-        tremors

-        difficulty walking and/or swallowing

-        dystonia

A hepatic copper test may be ordered to further investigate copper storage when copper and ceruloplasmin results are abnormal or equivocal.
Reference range values

Abnormal findings

Copper serum test results must be evaluated in context and are usually compared to ceruloplasmin levels. Abnormal copper results are not diagnostic of a specific condition; they indicate the need for further investigation.

Interpretation can be complicated by the fact that ceruloplasmin is an acute phase reactant - it may be elevated whenever inflammation or severe infections are present.

Both ceruloplasmin and copper are also increased during pregnancy and with estrogen and oral contraceptive use.

Low blood copper concentrations along with increased urine copper levels, low ceruloplasmin levels, and increased hepatic copper are typically seen with Wilson's disease.

Increased blood and urine copper concentrations and normal or increased ceruloplasmin levels may indicate exposure to excess copper or may be associated with conditions that decrease copper excretion - such as liver disease. Increased hepatic copper may be present with chronic conditions. 

Decreased blood and urine copper concentrations and decreased ceruloplasmin may indicate a copper deficiency.

A normal hepatic copper test may indicate that copper metabolism is functioning properly or that the distribution of copper in the patient's liver is uneven and the sample is not representative of the person's condition.

If a patient is being treated for excess copper storage with chelators, then his 24-hour urine copper levels may be high until body copper stores decrease. Eventually, blood copper and 24-hour urine copper concentrations should normalize.

If someone is being treated for a condition related to copper deficiency and his ceruloplasmin and total copper concentrations begin to rise, then the condition is likely responding to the treatment.

Total serum copper concentrations are normally low at birth, rise over the next few years, peak, and then decline slightly to a relatively stable level.