Who is at risk for Wilson's disease?
Wilson's disease is transmitted as an autosomal recessive disease, which means that both parents must carry the defective ATP7B gene. More than 30 different mutations currently are identified, thus making it difficult to devise a successful means of genetic screening. However, if the mutation in a particular family can be located, a genetic diagnosis may then be made. This diagnosis may help in locating symptom-free relatives who will benefit from early treatment. A child of parents with the defective gene has a 25 percent chance of developing Wilson's disease, as does his or her siblings. Since early treatment is important, family members should be tested immediately. The carrier frequency is about 1 in 90. While carriers may experience mild difficulties, their symptoms are rarely medically significant and for this reason, carriers should not be treated.
What are the symptoms that lead to a diagnosis?
Despite the genetic nature of the disease, pathological changes and clinical manifestations do not appear before the age of 3. The majority of individuals with Wilson's disease will show symptoms in their teens, twenties, or thirties, but some cases will not manifest until the forties or fifties. In addition, Wilson's disease is often undiagnosed or diagnosed in the later stages because it is not considered, or the tests that would show a diagnosis are not performed. Since the disease affects many different tissues and organs, it has a wide range of neurological, psychiatric, and physical symptoms. In about half of those individuals with Wilson's disease, the liver is the primary organ affected; therefore, they may often be misdiagnosed as having cirrhosis, chronic active hepatitis, or fulminant hepatitis. Copper accumulation in the brain can present itself in the form of psychiatric disorders such as depression or suicidal impulses, or in the form of neurological symptoms such as slurred speech, tremors, or difficulty in swallowing. The most widely recognized symptoms of Wilson's disease are: tremors or chorea; gait disturbance and balance disorders; stiffness or rigidity; abnormal reflexes or speech; drooling; difficulty swallowing; abnormal eye movements; psychiatric disorders; hemolytic anemia; liver disease or liver-function abnormalities; and symptoms resembling Parkinson's disease. However, the most characteristic indicator of Wilson's disease is the Kayser-Fleischer ring, which is a copper deposit in the membrane of the cornea of the eye that produces a rusty brown ring that can often be seen during an eye exam.
While the presence of the Kayser-Fleischer ring is diagnostic, it is not always present in all people with Wilson's disease. Therefore, diagnosis should be made through tests that measure the amount of copper in the blood, urine, and liver. The most accurate screening test is a 24-hour urine measurement of copper. Other tests may reveal that the serum ceruloplasmin concentrations are low or in the low-normal range. In some cases a liver biopsy may be performed to determine the amount of copper in the liver.
What are the treatment goals and options?
The goal for treatment of Wilson's Disease is twofold. The toxic concentration of copper in the body must not only be removed, but its reaccumulation must also be prevented. Initially, doctors used a drug known as BAL, which was administered via a series of painful injections and also caused frequent side effects. In 1956, Dr. John M. Walshe began using a derivative of penicillin known as penicillamine to treat Wilson's disease. Administered orally, this new drug replaced the painful injections of BAL and became recognized for its effective chelating therapy. Chelators are drugs that have the ability to combine with a metal, such as copper, enabling it to be pulled from the body tissues and excreted. Until recently, the two chelation-therapy drugs of choice were trientine and penicillamine. However, many of the side effects of these two drugs can be serious. In the early stages of treatment, both drugs briefly raise the level of copper in the brain. This temporary abundance of copper in the brain can lead to lasting neurological damage. In addition, many individuals develop an allergic reaction to penicillamine within the first two weeks of taking the drug. This reaction may cause a rash, fever, and abnormalities in blood counts. Other serious side effects include vomiting, arthritis, lupus-like symptoms, anorexia, and nausea. The most threatening side effects of penicillamine are kidney disease, blood cell complications, and Goodpasture's syndrome, a potentially fatal disorder caused by kidney failure and lung hemorrhage.
Currently, the safest treatment for Wilson's disease is zinc acetate (market name Galzin[TM]). This treatment, developed by Dr. George Brewer, has been effective not only in "decoppering" those newly diagnosed with Wilson's disease, but also as a maintenance therapy. While zinc is not a chelator, it does prevent copper absorption in the intestines, is non-toxic, and does not produce life-threatening side effects. Dr. Brewer has also done extensive research on a third drug, ammonium tetrathiomolybdate. While zinc works slowly as an initial treatment, Dr. Brewer has found excellent results in more than 60 people with Wilson's disease when using ammonium tetrathiomolybdate in the initial treatments stages, followed by a regimen of zinc acetate for maintenance therapy. Unfortunately, tetrathiomolybdate therapy has not yet entered the long, arduous FDA (Food and Drug Administration) approval process.
For those with severe advanced liver disease, liver transplants have been successful by correcting the metabolic defect that appears to cause copper accumulation.
Non-drug treatment, especially diet modification, has proven to be the least effective means of treating Wilson's disease. While almost all foods contain some copper, most contain less than previously thought. Only two foods, liver and shellfish, are restricted for people with Wilson's disease because they are high in copper.
Wilson's disease is treatable and the outlook is excellent if treatment begins early in the course of the disease. Early diagnosis and treatment can lead to the elimination of the damaging copper deposits, while reversing many of the symptoms that interfere with normal functioning. The Kayser-Fleischer rings disappear and individuals can lead productive lives while receiving lifelong treatment. Left undiagnosed or untreated, the disease is fatal.
For more information on Wilson's disease or zinc acetate, contact the Wilson's Disease Association, 4 Navaho Dr., Brookfield, CT 06804-3124; Phone: (800) 399-0266; Web site: http://medhelp.org/wda/wil.htm.
H. Ascher Sellner, MD, is president of the Wilson's Disease Association, vice president of the National Center for the Study of Wilson's Disease, and has served on the board of directors of the National Organization for Rare Disorders (NORD) since 1998. Dr. Sellner has Wilson's disease and treats it with zinc acetate. He resides in Connecticut
|Printer friendly Cite/link Email Feedback|
|Author:||Sellner, H. Ascher|
|Publication:||The Exceptional Parent|
|Date:||Mar 1, 2001|
|Previous Article:||Never Give Up Hope.|
|Next Article:||"CYBER SUMMER CAMP".|