What is Ceruloplasmin?

Ceruloplasmin is a protein that carries over 90% of the copper in the blood. It is also involved in iron metabolism and has an official name of ferroxidase. There is a test for ceruloplasmin blood serum levels that rules out rare copper deficiency diseases.
Copper is obtained from the human diet and required for a number of functions in the body. Although absorbed in the intestines, the liver either stores it, or produces it for a number of different enzymes. Ceruloplasmin is first synthesized in a form lacking the copper ion. This form is unstable and degrades rapidly if copper is not added to it. The liver adds six to seven molecules of copper to the precursor form, and introduces the copper-carrying enzyme into the bloodstream.

The ceruloplasmin test is a blood test that indicates the levels of this protein in the blood serum. It is not a routine test and is primarily ordered to help diagnose a rare genetic disorder called Wilson’s disease. With this disorder, the liver fails to incorporate copper into the ceruloplasmin protein. Toxic levels of copper accumulate in the brain, liver, and other organs. This disease is fatal unless the person is rapidly treated with copper chelators.

Chelators are molecules that bind to metals. They are used medicinally to treat patients with excess metals in their bodies. The chelators are introduced, bind the metal, and are then removed from the bloodstream, along with the excess metal. Different types of chelators bind different kinds of metals.

There is another rare genetic disease called aceruloplasminemia that is caused by a mutation in the ceruloplasmin gene. Normally this enzyme removes iron from cells. In its absence, toxic levels of iron build up in the liver, brain, pancreas, and retina. As individuals reach middle age, diabetes and the symptoms of Parkinson Disease develop. It is possible to stop the progression of these complications by treatment with an iron-chelating agent.

Other reasons for low ceruloplasmin levels include a very rare syndrome known as Menkes disease. Copper deficiency is another reason, as is an overdose of vitamin C. Low levels alone cannot be used to diagnose a specific condition. The results are usually considered along with tests for copper levels.

Reasons for elevated levels can include severe infection, tissue damage, and both chronic and acute inflammation. Pregnancy is another reason for increased levels of ceruloplasmin. Additional reasons can include lymphoma, rheumatoid arthritis, systemic lupus erythematosus, and various cancers — along with brain disorders, such as obsessive-compulsive disorder, schizophrenia, and Alzheimer’s Disease. The use of oral contraceptives and estrogen can also cause increased levels.