Definition
- Copper is a metal component of various enzymes (e.g., cytochrome oxidase, superoxide dismutase, tyrosinase) involved in Hb synthesis, bone and elastic tissue development, and CNS function. Copper test levels need to be evaluated and compared to ceruloplasmin levels.
- Normal range: see Table 16.23.
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TABLE 16 " “23Normal Levels of Serum CopperView LargeTABLE 16 " “23Normal Levels of Serum Copper Age Male (mg/dL) Female (mg/dL) ≤6 mo 20 " “70 20 " “70 7 mo " “18 y 90 " “190 90 " “190 ≥19 y 70 " “140 80 " “155
Use
- Aids in the diagnosis of Wilson disease
- Assessment of primary biliary cirrhosis
- Assessment of primary sclerosing cholangitis
Interpretation
Increased In
- Wilson disease (low to normal, total copper blood, high free serum, and urine copper)
- Anemias
- PA
- Megaloblastic anemia of pregnancy
- Iron deficiency anemia
- Aplastic anemia
- Leukemia and lymphoma
- Infection, acute and chronic
- Biliary cirrhosis and sclerosing cholangitis
- Hemochromatosis
- Collagen diseases (including SLE, RA, acute RF, GN)
- Hypothyroidism
- Hyperthyroidism
- Frequently associated with increased CRP
- Ingestion of oral contraceptives and estrogens
- Pregnancy
Decreased In
- Wilson disease: Mutation interferes with copper transport from intestinal mucosal cytoplasm to Golgi apparatus, where it becomes bound to protein
- Menkes kinky hair syndrome
- Nephrosis (ceruloplasmin lost in urine)
- Acute leukemia in remission
- Some iron deficiency anemias of childhood (that require copper as well as iron therapy)
- Kwashiorkor, chronic diarrhea
- ACTH and corticosteroids
Limitations
- Serum copper may be elevated with infection, inflammation, stress, RA, with some cancers, medications such as carbamazepine and phenobarbital.
- Concentrations are 2 " “3 ƒ — normal in the third trimester of pregnancy.
- Copper may be lowered with corticosteroids, zinc, malnutrition, and malabsorption.
- Serum specimen should be collected in a trace element-free tube, such as royal blue sterile tube, to avoid contamination.
- High urinary copper levels support the diagnosis but are not unique to Wilson disease, as they can be sometimes observed in autoimmune hepatitis and cholestasis.