Patient Test Information

Copper

Also known as:

Cu; Urine Copper; Blood Copper; Free Copper; Hepatic Copper

Formal name:

Copper, 24-hour urine, total and free blood, and liver (hepatic) tissue

Related tests:

Ceruloplasmin; Trace Minerals; Heavy Metals

Board approvedAll content on Lab Tests Online has been reviewed and approved by our Editorial Review Board.

Why Get Tested?

To measure the amount of copper in the blood, urine, or liver tissue; to help diagnose and monitor Wilson disease; sometimes to identify copper deficiency or excess

When to Get Tested?

When you have jaundice, fatigue, abdominal pain, behavioral changes, tremors, or other symptoms that a health practitioner thinks may be due to Wilson disease or, rarely, to copper deficiency or excess; at intervals when you are being treated for a copper-related condition

Sample Required?

A blood sample drawn from a vein in your arm and/or a 24-hour urine sample; sometimes a liver biopsy sample

Test Preparation Needed?

None

How is it used?

Copper testing is primarily used to help diagnose Wilson disease, a rare inherited disorder that can lead to excess storage of copper in the liver, brain, and other organs. Less commonly, a copper test may be used to detect copper excess due to another condition, to detect a copper deficiency, or to monitor treatment for one of these conditions.

Copper is an essential mineral but in excess, it can be toxic. In the blood, most of it is incorporated into the enzyme ceruloplasmin and only a small amount is in a "free" or unbound state. (See the "What is being tested?" section for more on this.)

Typically, a total blood copper test is ordered along with a ceruloplasmin level. If the results from these tests are abnormal or unclear, then they may be followed by a 24-hour urine copper test to measure copper elimination and/or a copper test performed on a liver biopsy to evaluate copper storage in the liver.

Sometimes a free (unbound) blood copper test is also ordered. If Wilson disease is suspected, genetic testing may be performed to detect mutations in the ATP7B gene. However, these tests have limited availability and are usually performed in special reference or research laboratories.

Rarely, a copper test may be used to help diagnose Menkes kinky hair syndrome, a rare inherited disorder of copper transport dysfunction. (See Common Questions #4.)

When is it ordered?

One or more copper tests are ordered along with Ceruloplasmin when someone has signs and symptoms that a health practitioner suspects may be due to Wilson disease, excess copper storage, or copper poisoning. These signs and symptoms may include:

  • Anemia 
  • Nausea, abdominal pain 
  • Jaundice 
  • Fatigue 
  • Behavioral changes 
  • Tremors 
  • Difficulty walking and/or swallowing 
  • Dystonia

Testing may be ordered when a person has signs and symptoms that may be due to a copper deficiency, such as:

  • Abnormally low numbers of neutrophils, a type of white blood cell (neutropenia)
  • Osteoporosis
  • Anemia
  • Less commonly, neurologic symptoms and delayed growth in children

One or more of the copper tests may be ordered periodically when monitoring is recommended.

A hepatic (liver) copper test may be ordered to further investigate copper storage when copper and ceruloplasmin results are abnormal or equivocal.

What does the test result mean?

Copper 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.

Test results may include:

Test Wilson Disease Copper Toxicity Menkes Disease (Kinky Hair Syndrome) Copper Deficiency
Copper, blood Low but may be normal High Low Low
Copper, serum free High High Low Low
Ceruloplasmin Low but may be normal High Low Low
Copper, urine Very high High Low Low
Copper, liver/hepatic* Positive but, depending on the site sampled, may be negative High or normal Low Low

*Excess copper in the liver is often unevenly distributed and may not be detected in a sample.

  • Low blood copper concentrations along with increased urine copper levels, low ceruloplasmin levels, and increased hepatic copper are typically seen with Wilson 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 chronic liver disease, or that release copper from tissues, such as acute hepatitis. 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 liver is uneven and the sample is not representative of the person's condition.

If a person is being treated for Wilson disease or copper toxicity with drugs that bind copper (chelators), then that person's 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 the person's ceruloplasmin and total copper concentrations begin to rise, then the condition is likely responding to the treatment.

Is there anything else I should know?

Medications such as carbamazepine and phenobarbital can increase blood copper levels. They may also be elevated with rheumatoid arthritis and with some cancers and decreased with a variety of conditions associated with malabsorption, such as cystic fibrosis.

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.

Care must be taken, especially with a 24-hour urine sample, not to contaminate the sample with an external source of copper. Talk to the health practitioner and/or the laboratory that will perform the test about necessary precautions. If a urine or blood copper test result is higher than expected, the health practitioner may have the test repeated with a new sample to confirm the findings.

What is being tested?

Copper is an essential mineral that the body incorporates into enzymes. These enzymes play a role in the regulation of iron metabolism, formation of connective tissue, energy production at the cellular level, the production of melanin (the pigment that produces skin color), and the function of the nervous system. This test measures the amount of copper in the blood, urine, or liver (hepatic).

Copper is found in many foods including nuts, chocolate, mushrooms, shellfish, whole grains, dried fruits, and liver. Drinking water may acquire copper as it flows through copper pipes, and food may acquire it when people cook or serve food in copper dishes. Normally, the body absorbs copper from food or liquids in the intestines, converts it to a non-toxic form by binding it to a protein, and transports it to the liver. The liver stores some of the copper and binds most of the rest to another protein called apoceruloplasmin to produce the enzyme ceruloplasmin. About 95% of the copper in the blood is bound to ceruloplasmin, and most of the rest is bound to other proteins such as albumin. Only a small amount is normally present in the blood in a free (unbound) state. The liver eliminates excess copper into the bile and it is removed from the body in the stool. Some copper is also eliminated in the urine.

Both excess and deficiency of copper are rare. Wilson disease, a rare inherited disorder, can lead to excess storage of copper in the liver, brain, and other organs. Copper excess (toxicity) can also occur when a person is exposed to and absorbs large amounts over a short period of time (acute exposure) or various amounts over a long period (chronic exposure).

Copper deficiency may occasionally occur in people who have conditions associated with severe malabsorption, such as cystic fibrosis and celiac disease, and in infants exclusively fed cow-milk formulas.

A rare X-linked genetic condition called Menkes kinky hair syndrome leads to copper deficiency in the brain and liver of affected infants. The disease, which affects primarily males, is associated with seizures, delayed development, abnormal artery development in the brain, and unusual gray brittle kinky hair.

How is the sample collected for testing?

A blood sample is obtained by inserting a needle into a vein in the arm and/or a 24-hour urine sample is collected. Sometimes a health practitioner performs a liver biopsy.

NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.

Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed.

  1. Should everyone's copper metabolism be evaluated?

    General screening for copper concentrations is not recommended or necessary. Many people with conditions not associated with copper, such as people with infections or inflammation, may have temporarily increased concentrations.

  2. Can I choose either a blood (total or free) or urine copper test?

    These tests provide complementary information and your healthcare provider will determine which tests are necessary to evaluate your condition.

  3. Should I be taking copper supplements or trying to get more copper in my diet?

    In most cases, a regular diet satisfies the body's requirements for copper. Talk to your healthcare provider before taking any supplements or changing your diet.

  4. What is Menkes kinky hair syndrome?

    Menkes kinky hair syndrome, also called copper transport disease, is a rare inherited disorder that causes a deficiency in copper. The syndrome is caused by mutations in the ATP7A gene located on the X chromosome. It is passed from parent to child in an X-linked recessive manner. This means that girls must inherit two copies of the mutated gene in order to be affected. Because boys only have one X chromosome, they can be affected if the mutation is present on the one X chromosome.

    The mutation leads to uneven distribution of copper in the body. It may build up in tissues of the intestines and kidneys, for example, but may be deficient in areas such as the brain. Symptoms of the syndrome typically develop in infancy and many children die at a young age. Signs and symptoms include sparse, kinky hair, failure to grow at an expected rate and developmental delay, nervous system deterioration, weak muscle tone and seizures. The incidence of this syndrome is about 1 in 100,000 infants.

NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used. To access online sources, copy and paste the URL into your browser.

Sources Used in Current Review

Sloan, J. and Feyssa, E. (2014 March 4). Copper. Medscape Drugs & Diseases [On-line information]. Available online at http://emedicine.medscape.com/article/2087780-overview through http://emedicine.medscape.com. Accessed December 2014.

Johnson, L. (Revised 2013 April). Copper Deficiency and Toxicity. Merck Manual Professional Edition [On-line information]. Available online through http://www.merckmanuals.com. Accessed December 2014.

Haldeman-Englert, C. (2013 January 4). 24-hour urine copper test. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003604.htm through http://www.nlm.nih.gov. Accessed December 2014.

(© 1995-2014). Copper, Serum. Mayo Clinic Mayo Medical Laboratories [On-line information]. Available online at http://www.mayomedicallaboratories.com/test-catalog/Overview/8612 through http://www.mayomedicallaboratories.com. Accessed December 2014.

Strathmann, F. (Updated 2014 March). Trace Minerals. ARUP Consult [On-line information]. Available online at http://www.arupconsult.com/Topics/TraceMinerals.html?client_ID=LTD#tabs=0 through http://www.arupconsult.com. Accessed December 2014.

Gilroy, R. (Updated 2014 May 2). Wilson Disease. Medscape Drugs & Diseases [On-line information]. Available online at http://emedicine.medscape.com/article/183456-overview through http://emedicine.medscape.com. Accessed December 2014.

(Last updated: 3/8/2011) Genetic and Rare Diseases Information Center (GARD). Menkes Disease. Available online at http://ghr.nlm.nih.gov/condition/menkes-syndrome through http://ghr.nlm.nih.gov. Accessed January 2015.

(Reviewed March 2009) Genetics Home Reference. Menkes Syndrome. Available online at http://rarediseases.info.nih.gov/gard/1521/menkes-disease/resources/1 through http://rarediseases.info.nih.gov. Accessed January 2015.

(Reviewed January 2014) Linus Pauling Institute. Micronutrient Information Center, Copper. Available online at http://lpi.oregonstate.edu/infocenter/minerals/copper/#deficiency through http://lpi.oregonstate.edu. Accessed January 2015.

Sources Used in Previous Reviews

Clarke, W. and Dufour, D. R., Editors (2006). Contemporary Practice in Clinical Chemistry. AACC Press, Washington, DC. Bankson, D. Chapter 35, Vitamins and Trace Elements: Assessment of Micronutrient Status through Laboratory Testing. Pp. 399 410.

Wu, A. (2006). Tietz Clinical Guide to Laboratory Tests, Fourth Edition. Saunders Elsevier, St. Louis, Missouri. Pp. 292-295.

Alexander, D. (2006 March 2, Updated). 24-hour urine Copper/Cu. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003604.htm. Accessed 7/21/07.

McGee, W. (2007 March 2, Updated). Copper in diet. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/002419.htm. Accessed 7/25/07.

Perez, E. (2006 October 23, Updated). Copper poisoning. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/002496.htm. Accessed 7/25/07.

(2004). Copper. ATSDR Division of Toxicology ToxFAQs [On-line information]. Available online at http://www.atsdr.cdc.gov/tfacts132.html through http://www.atsdr.cdc.gov. Accessed 7/25/07.

(2007 February 13, Updated). Menkes Disease Information Page. NINDS [On-line information]. Available online at http://www.ninds.nih.gov/disorders/menkes/menkes.htm through http://www.ninds.nih.gov. Accessed 7/25/07.

(2007 February 14). Zellweger Syndrome Information Page. NINDS [On-line information]. Available online at http://www.ninds.nih.gov/disorders/zellweger/zellweger.htm through http://www.ninds.nih.gov. Accessed 7/25/07.

Thomas, Clayton L., Editor (1997). Taber's Cyclopedic Medical Dictionary. F.A. Davis Company, Philadelphia, PA [18th Edition]. Pp. 441.

Copper. Merck Manual of Medical Information Second Home Edition [On-line information]. Available online at http://www.merck.com/mmhe/print/sec12/ch155/ch155c.html through http://www.merck.com. Accessed 7/17/07.

Das, S. and Ray, K. (2006 October 13). Wilsons Disease: An Update. Medscape from Nature Clinical Practice Neurology [On-line information]. Available online at http://www.medscape.com/viewarticle/543866 through http://www.medscape.com. Accessed 7/27/07.

Turnlund, J. (2007 July, Reviewed). Copper. Linus Pauling Institute Micronutrient Research for Optimum Health, Micronutrient Information Center, Oregon State University [On-line information]. Available online at http://lpi.oregonstate.edu/infocenter/minerals/copper/ through http://lpi.oregonstate.edu. Accessed 9/16/07.

(2006 August 1). Copper. MedlinePlus Health Information, Herbs and Supplements [On-line information]. Previously available online at http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-copper.html. Accessed 9/16/07.

Barnes, N. et. al. (2005). The copper-transporting ATPases, menkes and wilson disease proteins, have distinct roles in adult and developing cerebellum. Medscape from J Biol Chem. 2005; 280(10): 9640-5 (ISSN: 0021-9258) [On-line abstract]. Available online at http://www.medscape.com/medline/abstract/15634671?src=emed_ckb_ref_0 through http://www.medscape.com. Accessed 9/16/07.

Shim, H. and Harris, Z. L. (2003 May). Supplement: 11th International Symposium on Trace Elements in Man and Animals, Genetic Defects in Copper Metabolism. J. Nutr. 133: 1527S-1531S [On-line journal article]. Available online at http://jn.nutrition.org/cgi/content/full/133/5/1527S through http://jn.nutrition.org. Accessed 9/16/07.

Greco, F. (Updated 2009 January 20). 24-hour urine copper test. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003604.htm. Accessed December 2010.

McMillin, G. and Roberts, W. (Updated 2010 May). Wilson Disease. ARUP Consult [On-line information]. Available online at http://www.arupconsult.com/Topics/WilsonDz.html?client_ID=LTD#tabs=0 through http://www.arupconsult.com. Accessed November 2010.

Haldeman-Englert, C. (Updated 2010 September 10). Wilson's disease. MedlinePlus Medical Encyclopedia [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/000785.htm. Accessed November 2010.

Johnson, L. (Revised 2008 August). Copper. Merck Manual for Healthcare Professionals [On-line information]. Available online at http://www.merckmanuals.com/professional/sec01/ch005/ch005c.html?qt=wilson disease&alt=sh#sec01-ch005-ch005c-534 through http://www.merckmanuals.com. Accessed November 2010.

McMillin, G. et. al. (2009 August 25). Direct Measurement of Free Copper in Serum or Plasma Ultrafiltrate. Medscape Today from American Journal of Clinical Pathology. 2009;131(2):160-165. [On-line information]. Available online at http://www.medscape.com/viewarticle/707416 through http://www.medscape.com. Accessed November 2010.

Kaler, S. (Updated 2009 May 28). Menkes Kinky Hair Disease. eMedicine [On-line information]. Available online at http://emedicine.medscape.com/article/946985-overview through http://emedicine.medscape.com. Accessed November 2010.

(© 1995-2010). Unit Code 8612: Copper, Serum. Mayo Clinic, Mayo Medical Laboratories [On-line information]. Available online at http://www.mayomedicallaboratories.com/test-catalog/Overview/8612 through http://www.mayomedicallaboratories.com. Accessed November 2010.

Wu, A. (© 2006). Tietz Clinical Guide to Laboratory Tests, 4th Edition: Saunders Elsevier, St. Louis, MO. Pp 292-295.

Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. Burtis CA, Ashwood ER, Bruns DE, eds. St. Louis: Elsevier Saunders; 2006, Pp 556-559, 1126-1130, 1378-1379.

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