Ataxia - telangiectasia

Causes

Ataxia-telangiectasia is inherited, which means it is passed down through families. It is an autosomal recessive trait. This means that both parents must provide a defective gene for the child to have symptoms of the disorder.

The disease results from defects in the ataxia telangiectasia mutated (ATM) gene. Defects in this gene can lead to abnormal cell death in various places of the body, including the part of the brain that helps coordinate movement.

Boys and girls are equally affected.

Symptoms

• Decreased coordination of movements (ataxia) in late childhood
  • Ataxic gait (cerebellar ataxia)
  • Jerky gait
  • Unsteady
• Decreasing mental development, slows or stops after age 10 - 12
• Delayed walking
• Discoloration of skin areas exposed to sunlight
• Discoloration of skin (coffee-with-milk-colored spots)
• Enlarged blood vessels in skin of nose, ears, and inside of the elbow and knee
• Enlarged blood vessels in the whites of the eyes
• Jerky or abnormal eye movements (nystagmus) late in the disease
• Premature graying of the hair
• Seizures
• Sensitivity to radiation, including medical x-rays
• Severe respiratory infections that keep coming back (recurring)

Exams and Tests

The doctor will perform a physical exam. Examination may show signs of the following:

• Below normal sized tonsils, lymph nodes, and spleen
• Decreased to absent deep tendon reflexes
• Delayed or absent physical and sexual development
• Growth failure
• Mask-like face
• Multiple skin coloring and texture changes

Possible tests include:

• Alpha fetoprotein
• B and T cell screen
• Carcinoembryonic antigen
• Genetic testing to look for mutations in the ATM gene
• Glucose tolerance test
• Serum immunoglobulin levels (IgE, IgA)
• X-rays to look at the size of the thymus gland

Treatment

There is no specific treatment for ataxia-telangiectasia. Treatment is directed at specific symptoms.

Support Groups

Ataxia Telangiectasia Children's Project - www.atcp.org

National Ataxia Foundation (NAF) - www.ataxia.org

Outlook (Prognosis)

Early death is common, but life expectancy varies.

Because persons with this condition are very sensitive to radiation, they should never be given radiation therapy, and no unnecessary x-rays should be done.

Possible Complications

• Cancer such as lymphoma
• Diabetes
• Kyphosis
• Progressive movement disorder that leads to wheelchair use
• Scoliosis
• Severe, recurrent lung infections

When to Contact a Medical Professional

Call your health care provider if your child develops symptoms of this disorder.

Prevention

Couples with a family history of this condition who are considering pregnancy may consider genetic counseling.

Parents of a child with this disorder may have a slight increased risk of cancer. They should have genetic counseling and more intensive cancer screenings.

Alternative Names

Louis-Bar syndrome

Update Date: 8/4/2011

Updated by: Chad Haldeman-Englert, MD, Wake Forest University School of Medicine, Department of Pediatrics, Section on Medical Genetics, Winston-Salem, NC. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.