Copper, RBC

The Copper, RBC test contains 1 test with 1 biomarker.

Brief Description: The Copper RBC (Red Blood Cell) test is a laboratory examination that measures the level of copper present within red blood cells. This test provides valuable insights into the body's copper metabolism and helps assess its nutritional status and potential toxicity.

Also Known As: Cu RBC Test, Cu Test, Blood Copper Test, RBC Copper Test, Hepatic Copper Test, Copper Blood Test

Collection Method: Blood Draw

Specimen Type: Red Blood Cells

Test Preparation: No preparation required

When is a Copper RBC test ordered?

When a health practitioner suspects Wilson disease, excess copper storage, or copper poisoning, one or more copper tests are requested along with ceruloplasmin.

When copper and ceruloplasmin results are abnormal or inconclusive, a hepatic copper test may be conducted to further evaluate copper storage.

What does a Copper RBC blood test check for?

Copper is an important mineral that the body uses to make enzymes. These enzymes are involved in the regulation of iron metabolism, the development of connective tissue, cellular energy production, the production of melanin, and nervous system function. This test determines how much copper is present in the blood, urine, or liver.

Nuts, chocolate, mushrooms, seafood, whole grains, dried fruits, and liver are all high in copper. Copper may be absorbed into drinking water as it passes through copper pipes, and copper may be absorbed into food as it is cooked or served on copper dishes. Copper is absorbed from food or liquids in the intestines, converted to a non-toxic form by binding it to a protein, and transported to the liver in normal circumstances. To make the enzyme ceruloplasmin, the liver saves some copper and binds the remainder to another protein called apoceruloplasmin. Ceruloplasmin binds about 95 percent of the copper in the blood, with the rest attached to other proteins like albumin. In a free condition, only a little amount is present in the blood. Excess copper is excreted by the liver in the bile, which is then excreted by the body in the feces. Copper is also excreted in the urine in small amounts.

Copper excess and deficiency are uncommon. Wilson disease is a rare genetic ailment that causes the liver, brain, and other organs to store too much copper. Excess copper can arise when a person is exposed to and absorbs high amounts of copper in a short period of time or little amounts over a long period of time.

Copper deficiency can arise in patients with severe malabsorption diseases such cystic fibrosis and celiac disease, as well as infants who are exclusively fed cow-milk formulas.

Menkes kinky hair syndrome is a rare X-linked hereditary disorder that causes copper shortage in the brain and liver of affected babies. Seizures, delayed development, aberrant artery growth in the brain, and unique gray brittle kinky hair are all symptoms of the condition, which mostly affects men.

Lab tests often ordered with a Copper RBC test:

When a Copper RBC test is ordered, it's often part of a broader evaluation to understand the underlying cause of the abnormal copper levels and to assess the impact on overall health. Here are some tests commonly ordered alongside it:

1. Serum Copper and Ceruloplasmin:

   • Purpose: To measure the level of copper in the blood and ceruloplasmin, a protein that binds and transports copper.
   • Why Is It Ordered: To provide a comprehensive assessment of copper status in the body. Ceruloplasmin levels can help differentiate between various causes of copper abnormalities.

2. 24-Hour Urine Copper:

   • Purpose: To measure copper excretion in urine over a 24-hour period.
   • Why Is It Ordered: To assess copper elimination and help diagnose conditions like Wilson's disease, a genetic disorder leading to abnormal copper accumulation.

3. Liver Function Test:

   • Purpose: To assess liver health.
   • Why Is It Ordered: Because copper metabolism is closely related to liver function, and disorders like Wilson's disease can significantly impact liver health.

4. Complete Blood Count (CBC):

   • Purpose: To evaluate overall blood health.
   • Why Is It Ordered: To check for signs of anemia or other blood-related issues that can accompany copper abnormalities.

5. Zinc Level:

   • Purpose: To measure the level of zinc in the blood.
   • Why Is It Ordered: To evaluate for zinc deficiency or toxicity, as zinc and copper levels can be interrelated (excess of one can lead to a deficiency of the other).

These tests, when ordered alongside a Copper RBC test, provide a comprehensive evaluation of copper metabolism and its impact on the body. They are crucial for diagnosing and managing conditions related to abnormal copper levels, such as Wilson's disease, and for guiding treatment decisions. The specific combination of tests will depend on the individual’s symptoms, clinical findings, and medical history.

Conditions where a Copper RBC test is recommended:

1. Wilson's Disease: This inherited disorder causes copper to accumulate in the liver, brain, and other organs, leading to various symptoms and complications.
2. Menkes Disease: An uncommon genetic disorder that results in poor copper absorption, leading to severe developmental issues.
3. Copper Deficiency: Insufficient copper intake or absorption can lead to anemia, impaired growth, and other health problems.

How does my health care provider use a Copper RBC test?

Copper testing is largely used to detect Wilson disease, a rare genetic ailment in which the liver, brain, and other organs accumulate an excessive amount of copper. A copper test is less usually used to detect copper excess caused by another ailment, to diagnose a copper deficit, or to track treatment for one of these conditions.

Copper is a necessary mineral, but too much of it can be harmful. The majority of it is bound to the enzyme ceruloplasmin in the blood, leaving only a little quantity "free" or unbound.

A whole blood copper test is usually ordered in conjunction with a ceruloplasmin level. If the findings of these tests are abnormal or ambiguous, a 24-hour urine copper test to monitor copper elimination and/or a copper test on a liver biopsy to check copper storage in the liver may be conducted.

A free blood copper test is sometimes ordered as well. If Wilson disease is suspected, genetic testing for mutations in the ATP7B gene may be undertaken. However, these tests are only available in a restricted number of locations and are usually carried out in specialized reference or research laboratories.

A copper test may be used to identify Menkes kinky hair syndrome, a rare inherited copper transport failure condition.

What do my Copper RBC test results mean?

Copper test findings are frequently linked to ceruloplasmin levels and considered in context. Copper results that are abnormal are not indicative of a specific illness; rather, they signal that more research is needed. Because ceruloplasmin is an acute phase reactant, it might be raised if inflammation or severe infections are present, making interpretation difficult. Ceruloplasmin and copper levels rise during pregnancy, as well as with the use of estrogen and oral contraceptives.

Wilson disease is characterized by low blood copper concentrations, elevated urine copper levels, low ceruloplasmin levels, and increased liver copper.

Elevated copper concentrations in the blood and urine, as well as normal or increased ceruloplasmin levels, may suggest excessive copper exposure or be linked to disorders that reduce copper excretion, such as chronic liver disease, or release copper from tissues, such as acute hepatitis. Chronic diseases can cause an increase in hepatic copper levels.

Copper deficiency is indicated by lower copper concentrations in the blood and urine, as well as lower ceruloplasmin levels.

A normal hepatic copper test could mean that copper metabolism is normal, or that the distribution of copper in the liver is uneven, and that the sample isn't reflective of the person's health.

If a person is being treated for Wilson disease or copper toxicity with copper-binding medicines, their 24-hour urine copper levels may be high until their body copper stores are depleted. Copper concentrations in the blood and urine should return to normal over time.

If a person is being treated for a copper deficient disorder and their ceruloplasmin and total copper levels start to rise, the condition is likely responding to the treatment.

Most Common Questions About the Copper RBC test:

Clinical Utility and Interpretation

What is the primary purpose of the Copper RBC test?

The Copper RBC test measures the amount of copper present in the red blood cells (RBCs). It helps determine if there's a deficiency or excess of copper in the body. Copper is an essential trace element vital for various physiological functions, such as iron metabolism and neurotransmitter synthesis.

How can Copper RBC test results influence treatment decisions?

Results from the Copper RBC test can guide healthcare professionals in managing conditions like Wilson's disease, Menkes disease, or other disorders related to copper metabolism. Depending on the results, interventions may range from dietary adjustments to medications that either increase copper absorption or facilitate its excretion.

Clinical Applications and Diagnoses

Why might someone undergo a Copper RBC test instead of a serum copper test?

While both tests evaluate copper levels in the body, the Copper RBC test specifically measures copper in red blood cells, offering a more accurate representation of long-term copper status. In contrast, serum copper levels can fluctuate based on various factors, like recent dietary intake, making them less reliable for assessing long-term copper balance.

Which conditions can be diagnosed or ruled out with the Copper RBC test?

Wilson's disease, a rare inherited disorder causing excessive copper accumulation in the liver or brain, can be diagnosed or ruled out using this test. Conversely, conditions causing copper deficiency, like Menkes disease, can also be detected.

Understanding Limitations and Challenges

How does the Copper RBC test differ from ceruloplasmin testing?

Ceruloplasmin is a protein that carries about 95% of the total copper in the blood. While the Copper RBC test directly measures copper levels in red blood cells, ceruloplasmin testing evaluates the level of this specific protein. In conditions like Wilson's disease, ceruloplasmin levels might be decreased, even if serum copper levels are within the normal range.

If a Copper RBC test reveals abnormal levels, what are the next steps?

If the Copper RBC test indicates abnormal copper levels, further diagnostic evaluations may be necessary, including genetic testing or liver function tests. Additionally, consultation with a specialist, such as a hepatologist or genetic counselor, might be recommended.

Additional Questions and Insights

Is the Copper RBC test used in isolation to determine copper levels in the body?

No, the Copper RBC test is often used in conjunction with other tests, like serum copper, 24-hour urine copper, and ceruloplasmin levels, to get a comprehensive understanding of copper metabolism in the body.

Can diet or nutritional supplements affect the results of the Copper RBC test?

Yes, a diet high in copper or taking copper supplements can influence the results. This is why it's crucial for patients to inform their healthcare provider about their dietary habits and any supplements they're taking before undergoing the test.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.