Lab Code : CU
Test Background Copper is an essential trace element. It is required for ferro-oxidase activity which is an essential stage for incorporation of iron into haem. Copper is absorbed in the intestines and then transported to the liver, where it is stored or used in the production of a variety of enzymes. Caeruloplasmin is a copper-containing enzyme that plays a role in the body’s iron metabolism. In the blood, 95 % is bound to caeruloplasmin and 5 % is free. It is used in conjunction with serum copper assay to help diagnose Wilson’s disease and evaluate copper metabolism.
Clinical Indications Iatrogenic deficiency (eg. total parenteral nutrition, excess zinc replacement) Inborn errors (eg. Wilson’s and Menkes diseases). Decreased serum copper and caeruloplasmin, plus an elevated urinary copper, are diagnostic of Wilson’s disease. Penicillamine test Symptoms including: anaemia, nausea with abdominal pain, jaundice, dysphagia, tremors, behavioural changes, Kayser-Fleischer rings and tremors
Reference Range Plasma: Over 6 months 12-20 μmol/L Plasma: 0-6 months 3-8 μmol/L Urine: <1 µmol/24 h
Sample Required Trace element free (royal blue top) preferred, serum (red top) or SST (gold top) accepted
Sample Volume 1 mL
Turnaround Time 2 weeks
Notes Copper absorption is blocked by zinc. Patients who are on zinc replacement may also suffer from copper deficiency.