Fabry Disease

Fabry disease is a rare hereditary disorder caused by a faulty gene in the body. It affects more males than females: It is estimated that 1 in 40,000 males has Fabry disease, whereas the estimated prevalence in the general population is 1 in 117,000 people.

Hereditary (or genetic) disorders are those that are passed down from parents to their children through the genes. One or both parents may carry an abnormal gene that, when passed along to their children, can result in disease. Since the Fabry disease gene is located on the X chromosome, the disease primarily affects males (although some females can also experience symptoms).

When people inherit the abnormal gene that causes Fabry disease, their bodies cannot produce enough of an important enzyme called alpha-galactosidase A (pronounced al-fa-ga-lak-toe-si-daze a) or alpha-GAL. Alpha-GAL is needed to clear certain cells in the body of a fatty substance called globotriaosylceramide (pronounced glow-bow-tri-oh-syl-ser-a-mide) or GL-3.

Alpha-GAL helps clear GL-3 from the cells by breaking it down into particles small enough to leave the cell and enter into the blood stream. Once these particles enter the blood stream, they are either eliminated or reused to build other substances.

Without enough alpha-GAL, GL-3 cannot be broken down into smaller particles. Therefore, GL-3 cannot leave the cells and instead accumulates inside. Over time, this build-up of GL-3 causes damage to the cells.

The most commonly affected cells are found in blood vessels and tissues of the kidney, heart, skin, and brain. The build-up of GL-3 in these cells can eventually lead to life threatening problems.

Because Fabry disease is rare and causes a wide variety of symptoms, it can be mistaken for other diseases. Therefore, people may have the disease for a long time before it is accurately diagnosed. This is a concern because the longer a person has Fabry disease, the more damage is likely to occur in the body's organs and tissues and the more serious the person's condition may become. The earlier Fabry disease is diagnosed, the earlier doctors can start treatment to manage symptoms and try to prevent further health problems.

One way to increase the likelihood of early diagnosis is to learn about the disease and who is at risk of developing it. For example, Fabry disease is inherited and people whose family members have the disease are more likely to have the disorder than others without a family history. It may also help to learn about the symptoms of Fabry disease, as well as how and when these symptoms may arise.

Because Fabry disease is rare, its symptoms are not always associated with the disease. There are, however, a number of signs and symptoms that are commonly experienced by people with Fabry disease. These may include:

Pain

Impaired sweating

Exercise intolerance

Skin rashes (angiokerotomas)

Corneal whorling

Gastrointestinal problems

Heart problems

Kidney problems

Nervous system problems

Psychological and social issues

Most of these symptoms can be attributed to GL-3 accumulation and the resulting damage to various parts of the body. Many of these symptoms are also common to other diseases, which may lead to misdiagnosis. In addition, people with Fabry disease may have all or only a few of the typical signs and symptoms. They may also experience different symptoms at different times throughout their lives. That's why it's important to discuss your symptoms and any risk factors that you may have (for example, family members with known or suspected Fabry disease) with your doctor.

Fabry disease can affect anyone who inherits the faulty gene - both males and females. Virtually all males with the Fabry gene develop the disease and are likely to express some or many of the classic Fabry symptoms. In women with the Fabry gene, however, symptoms can range from none (in asymptomatic carriers) to very serious manifestations similar to those seen in males. That's because the level of symptom severity often depends on the amount of alpha-GAL enzyme produced in the body. Females with the faulty gene can have anywhere from near-normal levels of alpha-GAL to no active enzyme. Males, on the other hand, usually have little or no active alpha-GAL and are more likely to experience more severe symptoms than females.

The earlier Fabry disease is diagnosed, the earlier health care providers can begin treatments to help manage symptoms and disease-related complications. However, because Fabry disease is uncommon and its symptoms are not well recognized or may be mistaken for those of other illnesses, diagnosis can be challenging.

The following symptoms are common to Fabry disease and may prompt physicians to suspect and test for Fabry disease: burning pain in the hands and feet, temperature intolerance, a purple-red rash in the midriff area (angiokerotoma), corneal whorling, and episodes of intense pain (Fabry crisis).

Because Fabry disease is an X-linked genetic disorder, it is more common in males than in females. However, females can have mild to moderate (or sometimes even severe) disease or can be asymptomatic carriers of the Fabry gene. Generally, enzyme assay testing is not useful for diagnosing Fabry disease in females. Instead, genetic testing can be done to either diagnose the disease in females or identify female carriers

If you or a family member experiences any or all of these symptoms, consult with your doctor. After an examination, he or she can determine whether to run a test for Fabry disease. This test, called an enzyme assay, measures the amount of alpha-GAL enzyme activity in the blood.

If you have Fabry disease, medical genetic counsellors and other health care professionals are invaluable resources for helping you with family planning.


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