What is Ataxia-Telangiectasia?
Ataxia-telangiectasia (A-T) is an inherited disease characterized by the loss of one's ability to coordinate movement (ataxia), a weakening of the immune system, and an increased risk for cancer. It is also typically characterized by small, red, spider-like blood vessels (telangiectasia) in the eyes and on the skin. A-T is caused by harmful genetic changes, or mutations, in the ATM gene, which is involved in the control of cell growth, cell division, and the repair of damaged DNA.
In most cases, A-T presents in early childhood. Children with the condition will begin to wobble or stagger and have poor balance. Children affected with A-T may exhibit delayed motor skills and slurred speech. They may also lose the ability to follow objects with their eyes. By the age of 7 or 8, children with the disease often lose the muscle control necessary to write, and most individuals require the use of a wheelchair by the age of 10. While neurological problems may impair their ability to communicate, those with A-T are usually of average or above-average intelligence.
Most individuals with A-T also have weakened immune systems, leaving them prone to infection, particularly in the lungs. Also, they are at an increased risk of developing cancers at an early age, particularly cancers of the blood (leukemia) or the immune system (lymphoma). These individuals are also hypersensitive to the type of radiation found in X-rays and used in cancer therapy and typically must avoid it.
Additional considerations for carriers
While carriers of A-T do not show symptoms of the disease, studies have shown that they do have an increased risk of developing cancer. Female carriers have an increased risk of developing breast cancer. Therefore, starting at age 40 or earlier, female carriers are recommended to have an annual mammogram and consider breast MRI to screen for cancer. Both male and female carriers may have an increased risk of developing pancreatic cancer. The exact risks for cancer depend on personal and family history, so carriers of ATM mutations should consider genetic counseling to determine the most appropriate screening recommendations.
How common is Ataxia-Telangiectasia?
The estimated prevalence of A-T is 1 in 40,000 to 1 in 100,000 individuals worldwide.
How is Ataxia-Telangiectasia treated?
While there is no cure for A-T, the symptoms of the disease may be addressed. Injections of gamma globulin may be prescribed to help boost the immune system. High-dose vitamins may also be recommended. Antibiotics are typically used for infections, and vaccines for influenza and pneumonia may be recommended, as these infections can be devastating to those with A-T. Physical, occupational, and speech therapies may also be useful and recommended.
What is the prognosis for an individual with Ataxia-Telangiectasia?
Nearly all children with A-T are wheelchair-bound by the age of 10, and teenagers and adults with the disease require help with everyday tasks, including dressing, eating, washing, and using the bathroom. Life expectancy for individuals with the condition is shortened, with death often occurring in early adulthood. A small number of affected individuals have survived into their forties or fifties. The most common causes of death from A-T are cancer, lung infection, or lung failure. Because their intelligence remains normal, many individuals with A-T graduate high school and college.