Test Details
Methodology
Inductively-coupled plasma/mass spectrometry (ICP/MS)
Result Turnaround Time
2 - 4 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
It is used, along with serum ceruloplasmin and urine copper, to test for Wilson's disease and (more often) in monitoring the nutritional adequacy of parenteral or enteral nutrition, especially when copper deficiency may be suspected because of ongoing gastrointestinal losses of the element (see table). The test is done in suspected copper toxicity in premature infants when they are acutely ill and may not be able to assimilate the copper in their prescribed nutrition; in acute copper intoxications; or in “Indian childhood cirrhosis,” an illness not limited to Indian children.1 Serum copper is low in Menkes syndrome. Copper in the CSF is reported to mirror the neurotoxicity of copper in Wilson's disease.2 Liver copper is used to confirm Wilson's disease and Menkes syndrome and may be measured in liver disease of uncertain etiology. It can confirm ICC in the right setting. Liver copper rises with time in biliary cirrhosis, but does not confirm the diagnosis.
Deficiency, Nutritional | Menkes Syndrome | Acute Copper Toxicity | ICC and Chronic Copper Toxicity | Wilson's Disease | Smoking, Inflammatory Conditions, Pregnancy, Estrogens | |
|---|---|---|---|---|---|---|
N = normal, ↑ = increase, ↑↑ = large increase, ↓ = decrease. | ||||||
Serum copper | ↓ | ↓ | ↑, ↑↑ | ↑ | N or ↓ | ↑, ↑↑ |
Serum ceruloplasmin | ↓ | ↓ | N (early) | ↑ | Usually ↓; may be N in children | ↑, ↑↑ |
Urine copper | ↓ | ↑ | ↑ | ↑ | ↑, ↑↑ | N |
CSF copper | N or ↑ | N | ||||
Liver copper | ↓ | ↓ | N (early) | ↑, ↑↑ | ↑↑ | N |
Limitations
Serum ceruloplasmin is an acute-phase reactant type protein, and since it binds a large portion of serum copper, both serum copper and ceruloplasmin increase under the influence of inflammatory conditions and estrogen. Serum copper is, therefore, elevated in pregnancy, in patients on estrogens and estrogen-containing contraceptive drugs, in rheumatoid arthritis, and a number of other pathologic entities. It may be low with low serum proteins as in nephrosis, malabsorption, and malnutrition without necessarily reflecting inadequate liver copper stores. It is reduced under the influence of ACTH or glucocorticoids, or valproate3 therapy. Although serum copper levels are usually ordered to work up possible cases of Wilson's disease, Menkes syndrome, and ICC, serum copper alone is of only limited value. Elevations in liver tissue copper are found in Wilson's disease but may occur also in other types of liver disease, especially in primary biliary cirrhosis.4
This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.
Footnotes
References
Custom Additional Information
The demand for sensitive noninvasive tests for Wilson's disease, especially for children in families where the disease is known to occur, has stimulated search for newer indices of copper metabolism. Urine copper after penicillamine load has recently been proposed.5
Specimen Requirements
Specimen
Serum or plasma
Volume
1 mL
Minimum Volume
0.4 mL
Container
Royal blue-top (EDTA) tube or royal blue-top without EDTA
Collection Instructions
Serum must be separated from cells within 45 minutes of collection and transferred to a certified metal-free plastic transport tube (PeopleSoft No. 111166). Plasma may be separated immediately and transferred to a certified metal-free transport tube (PeopleSoft No. 111166) for shipment to the laboratory.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 28 days |
Refrigerated | 28 days |
Frozen | 28 days |
Freeze/thaw cycles | Stable x4 |
Reference Range
Age / Male | |
0 to 4 m | 38–122 |
5 to 6 m | 55–131 |
7 to 10 m | 64–142 |
11 m to 5 y | 81–152 |
6 to 10 y | 80–141 |
11 to 15 y | 67–128 |
16 to 30 y | 63–121 |
>30 y | 69–132 |
Age / Female | |
0 to 4 m | 38–122 |
5 to 6 m | 55–131 |
7 to 10 m | 64–142 |
11 m to 5 y | 81–152 |
6 to 10 y | 80–141 |
11 to 15 y | 67–128 |
16 to 18 y | 71–146 |
>18 y | 80–158 |
Storage Instructions
Maintain specimen at room temperature.
Causes for Rejection
Certified metal-free plastic transport tube not submitted; unspun royal blue-top tube from which the plasma or serum has not been removed; gel-barrier tube
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 001586 | Copper, Serum or Plasma | 5631-7 | 001586 | Copper, Serum or Plasma | ug/dL | 5631-7 |
| Order Code | 001586 | |||||
| Order Code Name | Copper, Serum or Plasma | |||||
| Order Loinc | 5631-7 | |||||
| Result Code | 001586 | |||||
| Result Code Name | Copper, Serum or Plasma | |||||
| UofM | ug/dL | |||||
| Result LOINC | 5631-7 |