Caeruloplasmin
Note: this site is for informational purposes only. To view test results or book a test, use the NHS app in England or contact your GP.
The caeruloplasmin test is performed on a blood sample to measure caeruloplasmin, a protein that transports copper in the bloodstream. It is used to help diagnose Wilson disease and other disorders of copper metabolism, and to investigate copper deficiency or liver-related conditions.
Why get tested?
Blood caeruloplasmin levels are measured; to help diagnose Wilson disease or conditions associated with copper deficiencies
When to get tested?
When you have symptoms that your doctor thinks are suggestive of Wilson disease or copper deficiency, or results from other blood tests suggest Wilson disease or copper deficiency is possible. It can also be tested at intervals when monitoring a copper related disease or its treatment.
Sample required?
A blood sample taken from a vein in your arm
Test preparation needed?
No test preparation is needed
Common questions
Caeruloplasmin is primarily measured with blood and/or urine copper to help diagnose Wilson disease, a rare inherited disease associated with low levels of caeruloplasmin and excess storage of copper in the liver, brain, and other organs. Rarely, it may be used to help diagnose a disorder of copper deficiency.
It is used along with copper measurements when someone has signs and symptoms that the doctor suspects may be due to Wilson disease such as:
- anaemia
- nausea
- tummy pain
- jaundice
- tiredness
- behavioural changes
- tremors
- difficulty walking and/or swallowing
- dystonia
Rarely, caeruloplasmin may also be requested with serum copper when your doctor suspects that you have a copper deficiency and periodically if monitoring is recommended.
- Low caeruloplasmin is seen in up to 90% of patients with Wilson disease, and would also be expected in cases of copper deficiency.
- However, low caeruloplasmin levels can sometimes be seen in patients who do not have Wilson disease or copper deficiency, so this alone cannot diagnose a copper related disease and needs to be interpreted with results of other tests such as urine/blood copper, clinical findings, or liver biopsy results
- A normal caeruloplasmin level does not definitively exclude Wilson disease as a small number of patients may have normal caeruloplasmin levels.
- Acute liver disease or high levels of oestrogen (e.g. contraceptive pill, hormone therapy or pregnancy) can also transiently increase low caeruloplasmin levels into the normal range.
Caeruloplasmin may be increased in a variety of circumstances which need to be considered when using it to diagnose or monitor Wilson disease or copper deficiency. These circumstances may include:
- Caeruloplasmin levels increases when someone has inflammation, severe infection, tissue damage, and some cancers.
- Increases are also seen during pregnancy and with the use of oestrogen, oral contraceptives, and medications such as carbamazepine, phenobarbital, and valproic acid.
Caeruloplasmin is not a routine test. Unless your doctor suspects that you have Wilson disease or a problem with your copper metabolism, it is unlikely that you will ever have this test performed.
If Wilson’s disease is strongly suspected, a liver biopsy may be performed to look for the copper content in the liver.