Generality
Ceruloplasmin is the main copper transport protein in the blood.
Consequently, anything that interferes with the supply of this mineral, or with the body's ability to metabolize it, can affect the blood concentrations of ceruloplasmin and copper itself.
What's this
Ceruloplasmin is a protein responsible for transporting copper in the blood . Most of the circulating metal is bound to it, while the remaining fraction is associated with albumin, trans-cuprein and minimally with amino acids.
Synthesized mainly by the liver, ceruloplasmin redistributes hepatic copper to tissues. It is not by chance that its name derives from coeruleus, which means blue, that is the color conferred by copper, which binds at the rate of six atoms per molecule.
In addition to intervening in the transport of copper, ceruloplasmin carries out numerous biological activities; it first possesses an oxidasic activity on different substrates. As regards iron, for example, it oxidizes the ferrous ion (Fe2 +) to the form of ferric ion (Fe3 +); in this way it allows the bonding of the metal to the transferrin (which can only transport the iron in the Fe3 + form), allowing its transfer from the deposit tissues to those of use. For the same reason it protects the central nervous system (CNS) from iron deposition.
Ceruloplasmin has an antioxidant action, since through the direct oxidation of Fe2 + and Cu2 + it prevents lipid peroxidation induced by these cations. It also acts as an acute phase protein in the inflammatory process, increasing its serum levels during inflammatory processes, severe infections, tissue damage and some types of cancer.
Why do you measure
Ceruloplasmin is measured to assess the metabolism of copper and facilitate the identification of some conditions associated with the deficiencies of this mineral.
The amount of ceruloplasmin in plasma is significantly reduced in Wilson's disease . This hereditary condition is characterized, in fact, by an accumulation of copper in the liver, in the central nervous system and in other organs.
In some cases, the ceruloplasmin dosage can be prescribed to help diagnose or make a differential diagnosis between different pathologies associated with copper deficiencies.
It should be noted that the finding of low levels of ceruloplasmin is not diagnostic for a specific pathology, therefore the blood concentration is usually evaluated together with other copper tests.
When is the exam indicated?
Ceruloplasmin dosage is not a routine test.
The examination is prescribed in the presence of signs and symptoms that the doctor believes may be due to Wilson's disease or, rarely, to copper deficiency, including:
- Jaundice;
- Fatigue;
- Abdominal pain;
- Changes in behavior;
- Tremors;
- Nausea;
- Dystonia;
- Difficulty walking and / or swallowing.
Normal values
The reference values for ceruloplasmin in the blood are in the range 20 - 60 mg / dL.
High Ceruloplasmin - Causes
In addition to copper intoxication, high serum ceruloplasmin levels occur during pregnancy and in women taking estrogen or combined oral contraceptives (estrogen plus progesterone).
As regards pathological states, a high ceruloplasmin is commonly found in cases of:
- Neoplastic diseases;
- Acute and chronic inflammatory states;
- Leukemia;
- Hodgkin's lymphomas;
- Primary biliary cirrhosis;
- cholestasis;
- Alzheimer's disease;
- Systemic lupus erythematosus;
- Rheumatoid arthritis.
Low Ceruloplasmin - Causes
Wilson disease
While in traces copper is an essential mineral for life, in excess it becomes strongly toxic.
The most obvious case is Wilson's disease, in which copper is deposited in the brain, liver, kidney and cornea. This rare hereditary disease is diagnosed on the basis of a series of laboratory findings: low ceruloplasmin, reduction of serum copper, increased concentration of metal in the urine and alteration of liver function indices.
The definitive diagnosis is obtained by demonstrating the impossibility of incorporating labeled copper into the ceruloplasmin.
Symptoms of Wilson's disease include anemia, nausea, abdominal pain, jaundice, asthenia, personality disorders, tremors, difficulty in walking and / or swallowing and dystonia.
Other Causes
Low values of this protein are also recorded in the Menkes syndromes (very rare disease), in aceruloplasminemia, in the excessive administration of zinc, in malnutrition and in all those conditions that determine a reduced synthesis or an increased loss of proteins (liver diseases in advanced stage that compromises protein synthesis, malabsorption syndrome, kidney diseases such as nephrotic syndrome).
How to measure it
To measure ceruloplasmin levels, the patient must have blood drawn from a vein in his arm. The dosage can be performed at regular intervals, when monitoring is recommended.
Preparation
Before undergoing the ceruloplasmin test, it is necessary to observe a fast of at least 8 hours. During this period, a small amount of water can be taken.
Interpretation of Results
The results of the ceruloplasmin test may depend on several pathological conditions:
- When blood concentrations of ceruloplasmin and copper are reduced, but mineral levels in urine are increased, the patient may suffer from Wilson 's disease ;
- If both ceruloplasmin and copper levels in blood and urine are low, the subject may have a copper deficiency .
