Fabry disease is an inherited disorder. A chemical in the body which would normally be broken down builds up and causes damage, mainly to the heart, kidneys and brain. This chemical that builds up is called ‘GL-3’.
In 1898, two Doctors - Dr Johann Fabry in Germany, and Dr William Anderson in England - independently published articles describing patients who had the disease. Dr Johann Fabry continued to work in this specialised area, and the disease was subsequently named after him. Much more work was conducted from that time to this, which has led toward developing a treatment for Fabry disease.
A chemical called ‘GL-3’ builds up in the body in Fabry disease, because it is not broken by the body.
An enzyme should break GL-3 down, but is missing or defective in Fabry disease. Chemical changes in the body need the help of enzymes to take place. There is a different enzyme for each type of chemical reaction in the body, so that thousands of enzymes make the body work. It is a bit like a production line in a factory, where a series of different machines make a series of changes to produce an end product, or to break down waste. If one machine on a factory production line were to break down, there would be a build up of half finished goods by the machine. This is what can happen if an enzyme in the human body is missing or defective.
In Fabry disease the missing enzyme is called alpha-galactosidase, and GL-3 is the chemical on which alpha-galactosidase should be acting.
Fabry disease can cause problems all over the body, because GL-3 builds up in the walls of blood vessels all over the body. The heart, kidneys and brain are mainly affected, and pain in the arms or legs is a common problem. Fabry disease is a serious condition. The disease can have variable effects, but often affected people develop complete kidney failure in their 20’s, and die of heart disease or stroke in their 30’s or 40’s. However, the new treatment with enzyme replacement (see below) may dramatically improve the outcome of this disease.
Fabry disease affects only males, but females can be carriers, and pass it onto their sons, or onto their daughters as carriers. Someone with Fabry disease should consult a specialist in genetic diseases. It should be possible to diagnose Fabry disease with a blood test. Modern techniques may enable someone with Fabry disease to have test-tube babies and guarantee that a child will not have have the disease, or be a carrier.
Occasionally women can also suffer from Fabry disease, and if this is the case, a specialist in genetic diseases should explain the inheritance pattern that would occur in that family.
Until 2001, the only treatment for Fabry disease was to try and cope with the problems it caused - such as using dialysis or kidneytransplantation for kidney failure. However, genetic engineering technology has enabled the production of large amounts of the enzyme, alpha-galactosidase, that is missing in people with Fabry disease.
The enzyme has to be given by injection. Trials have shown that the replacement enzyme removes GL-3 from the blood and from tissues where it has built up. These effects are very dramatic, and it is possible that people treated from childhood may never develop the serious consequences of Fabry disease, but lead normal lives. For people with established problems from Fabry disease, it is hoped that the disease will not progress. However, damage that has already been done to the brain, heart and kidneys would not be reversed.
The injections of enzyme need to be given every 2 weeks or so. There is a small risk of an allergic reaction, so for an initial phase the injections must be given in hospital. The allergic reaction means that some people cannot continue treatment with the enzyme.
Anyone with Fabry disease who has not already discussed enzyme treatment with their doctors should do so.