Suitable Specimen Types
- 24 Hour Urine Plain
Sample Processing in Laboratory
Place in toxicology box in cold room.Turnaround Time
2 weeksSample Stability
UsualUrine Copper
General Information
Copper is an important trace element which funtions as a catalytic component of numerous enzymes and is also a structural component of other important proteins.
A deficiency of copper has been noted in a number of conditions including malnourishment, malabsorption syndromes, prematurity, cardiovascular disease and Menkes syndrome. Raised values are seen in inflammatory states and with steroid hormone therapy. When investigating Wilson Disease, plasma/serum copper measurement is only of value as an addition to plasma caeruloplasmin concentration and 24 hour urinary copper excretion.
Caeruloplasmin and 24 hour urinary copper should be used for the initial investigation of Wilson's Disease, due to the many potential problems of interpreting the serum copper concentration.
To distinguish Wilson's Disease from other forms of hepatic dysfunction, may require measurement of 24 hour urinary Cu excretion before and after penicillamine challenge. Consult this laboratory or the SAS Trace Elements Handbook.
Cu IUDs do not appear to increase excretion of or urine content of the element.
Patient Preparation
Indications - Hepato-biliary dysfunction (inc. Wilson's Disease), toxicity, occupational exposure.
Notes
Note that a spot urine is not suitable for Wilson's Disease investigations as the results are not easily interpreted.
Reference Range
Reference Ranges (pre-chelation)
Normal excretion usually <0.8 umol/24 hours.
Cholestasis, hepatic cirrhosis, covert Wilson's Disease >0.8 umol/24 hours
Patients with frank Wilson's Disease or acute hepatic crisis >1.6 umol/24 hours
(Source: SAS Trace Element Analysis, 4th Edition, 2006).
Specifications
- EQA Scheme?: Yes
- EQA Status: NEQAS