Wilson's diseaseThis rare disease is characterized by an alteration in the transport and disposal of copper which comes from the diet, which has just been deposited in the liver, the brain and the cornea, causing disntintos problems.
Wilson's disease is by definition a hereditary disease that is characterized by an alteration in the transport and disposal of copper which comes from the diet, which brings as a consequence in the long term the deposit of this metal in three bodies mainly: the liver, the brain and the cornea of the eye, with consequential faults in them.
Wilson's disease is considered a rare disease, its frequency in almost all populations studied is one per 40,000 inhabitants. People carrying the mutation frequency - but in which no disease appears not to be a dominant mutation - it is close to 1%.
What happens with copper metabolism?It is estimated there about 50-100 mg of copper that are necessary to carry out different functions of metabolism in the body. And through the food we eat every day about 2-5 mg of this trace element.
In patients with Wilson's disease, the intermediary metabolism of copper is altered due to a mutation in the ATP7Bgene. This gene encodes a protein, called in the same way, which is required for the removal of copper in the bile and that copper passing to ceruloplasmin, which is the protein that transports copper in the blood. In the absence of a correct disposal of copper through the bile, there is a tendency to excessive accumulation of this metal, which cause injury liver that can start even from the three years of life.
With the progression of the disease, the concentration in the serum of unbound to protein copper - also called free copper - produces this metal deposit in other locations of the human body, mainly in the Central nervous system, which brings with it level of neurological and psychiatric disorders symptoms.
On the other hand, ceruloplasmin, a protein synthesized in the liver responsible for transporting the 95% copper in the body, is decreased by a defective incorporation of copper to the protein. This fact can help to diagnosis, because measurable levels of ceruloplasmin in blood and, in case of disease, these levels are abnormally low.
How is it inherited?Wilson's disease is inherited in a manner autosomal recessive, i.e. to make it appear disease should inherit the mutation in the gene, ATP7B both the father and the mother. People who inherit the mutation from one parent but not the other are carriers of the mutation, but do not develop the disease.
In the ATP7B gene mutation is not always the same, they have been described in the medical literature more than 350 possible mutations in this gene.
How and when Wilson disease manifested?Wilson's disease mainly affects the liver, being one of its earliest manifestations of this organ inflammation, what is known in medical terms as hepatitis. When this happens there is a release into the blood stream and liver enzymes, known as transaminases, bilirubin, substance responsible for the yellowish colour that takes the skin and mucous membranes of these patients (jaundice). Hepatitis tends to heal on their own, but it can be repeated several times and the patient can eventually develop a chronic inflammatory process of the liver, causing normal tissue is destroyed and is replaced by fibrous tissue, causing what is known as cirrhosis of the liver. When this happens the liver is unable to function properly.
The other type of clinical manifestation of Wilson's disease occurs at the neuro-psychiatric level, and is characterized by alterations of movement, tremors and lack of coordination, difficulty in speech and trouble swallowing food. Also loss of memory, decline of intellectual performance, headaches, behavior disorders, neurotic or psychotic manifestations, symptoms of dementia and seizures can occur.
The eyeball involvement is also very common. The most affected by inappropriate copper deposit is the cornea, in its most outer diameter, resulting in a phenomenon known as Kayser-Fleischer rings. This ring is produced by copper deposit initially at the top and bottom poles after surrounding the iris and the cornea. This ring can be detected in an ophthalmologic examination, which can help the diagnosis of Wilson's disease. On the other hand can lead to hardening of the lens and increasing the opacity of the same, referred to as falls.
Diagnosis of Wilson's diseaseParamount to be able to diagnose Wilson's disease is clinical suspicion, based on the signs and symptoms of the patient and the alterations in liver function tests. At a clinical suspicion, you can perform the following tests:
- Quantification of copper in the urine in 24 hours. Values higher than 100 micrograms day are common in these patients (the values for a healthy person ranged from 20 to 50 micrograms/day).
- Free in serum copper levels. In Wilson's disease are over the age of 25 microgram/dl.
- Ceruloplasmin in serum levels. They are handicapped in this disease, usually below 20 mg/dl.
- Presence of Kayser-Fleischer rings in the eye. This alteration is usually detected by an ophthalmologist using a special light called slit-lamp.
- Genetic Test to detect the DNA of the gene mutation patient, for which used genetic sequencing techniques. Screening of first-degree relatives under 40 years of age is also important.
- Imaging studies: if the patient is having symptoms neuro-psychiatric usually request an MRI (magnetic resonance imaging) of the brain, thus allowing to detect deposits of copper and cerebral atrophy.
- If it is necessary to make a differential diagnosis with other liver diseases that are with the same symptoms, it is advisable to perform a liver biopsy to determine the concentration of hepatic copper. Biopsy diffuse inflammatory changes, fibrosis, deposits are found in fat and copper. In addition to diagnose the disease, the biopsy allows to determine the degree of involvement of the liver by copper deposit.
Treatment of Wilson's diseaseWilson's disease does not cure permanently, treatments can only be applied for by life aimed to control the deposit of copper in the body.
To do this, firstly should be recommended to the patient make changes in their eating habits and avoid those that are especially rich in copper, such as products derived from cocoa, products of animal origin as viscera, some vegetables and vegetables such as broccoli, seafood in general or nuts such as walnuts, hazelnuts, almonds, peanuts.
Secondly, from the point of view of therapeutic available medicines are currently aimed to reduce deposits of copper, through a chemical process called Chelation, i.e. drugs bind copper irreversibly and facilitate their elimination via kidney or bowel. The most common are penicillamine (increasingly obsolete by their adverse neurological level), Trientine, and zinc acetate.
The latest recommendations point to start the treatment with zinc acetate as soon as possible, even in patients with homozygous for the mutation that still have not shown symptoms. Zinc acetate, moreover, is the treatment of choice in pregnant women and in children.
Thirdly, if the patient requires it, i.e. If he has liver failure, liver transplantation may be performed.