The ataxia telangiectasia based on a DNA repair defect, which often results in humoral and cellular immune deficiencies; it causes progressive progressive cerebellar ataxia, oculocutaneous telangiectasia and recurrent infections sinopulmonary.
(See also Overview of Immunodeficiency Disorders and approach to the patient with an immunodeficiency disorder.)
The ataxia telangiectasia based on a DNA repair defect, which often results in humoral and cellular immune deficiencies; it causes progressive progressive cerebellar ataxia, oculocutaneous telangiectasia and recurrent infections sinopulmonary. (See also Overview of Immunodeficiency Disorders and approach to the patient with an immunodeficiency disorder.) Ataxia telangiectasia-is an autosomal recessive primary immunodeficiency disease, which includes the combined humoral and cellular defects. The estimated incidence is 1 out of 20,000 to 100,000 births. It is caused by mutations in the gene coding for the mutant with ataxia telangiectasia ATM protein. ATM is involved in the detection of DNA damage and helps to control the rate of cell growth and cell division. Patients often do not have IgA and IgE, and show a progressive disorder of the T cells. Symptoms and complaints The age at onset of neurological symptoms and the evidence of immunodeficiency vary. Ataxia is often the first symptom and it develops normally, when the children start running. The progression of neurological symptoms leading to severe disability. The language is washed out, there is choreoformen movements and nystagmus, and muscle weakness usually progresses to muscle atrophy. Telangiectasia usually occur only between 4 and 6 years on; They are most noticeable on bulbar conjunctiva, ears, elbows and knees and on the sides of the neck. Recurrent infections sinupulmonale lead to repeated pneumonia, bronchiectasis and chronic restrictive lung disease. Certain endocrine disorders (eg. B. gonadal dysgenesis, testicular atrophy, diabetes mellitus) can be present. The incidence of cancer (particularly leukemia, lymphoma, brain cancer and gastric cancer) is high. The cancer usually occurs after the age of 10 years and at a rate of about 1% / year; However, it represents a lifetime risk and can occur at any age. Diagnosis IgA and serum alpha-1-fetoprotein levels genetic tests The following clinical findings allow the diagnosis of ataxia telangiectasia: ataxia (especially if telangiectasia are available) Low levels of IgA (in 80% of patients with this condition) High concentrations serum alpha-1-fetoprotein When a karyotype analysis was performed frequently occur chromosome breaks that are consistent with a defect in the DNA repair on. The diagnosis of ataxia telangiectasia is confirmed by the identification of mutations in both alleles of the gene for ATM proteins. Because the carrier ataxia telangiectasia-mutation usually remain asymptomatic, the testing of siblings can help a carrier state about to predict the probability of having an affected child. The test for endocrine disorders and cancer is made based on the clinical presentation. Supportive therapy treatment with prophylactic antibiotics or immunoglobulin (IgG) -Ersatztherapie Treatment with prophylactic antibiotics or immunoglobulin may help patients with ataxia telangiectasia. In a small study, treatment with amantadine led to minimal improvement in motor function, but there is no effective treatment for the progressive neurological deterioration that leads to death, usually after age 30. Chemotherapy is often indicated for the treatment of associated cancers.