| Subject | Contents |
| Definition | Friedreich ataxia is an inherited form of progressive dysfunction of the cerebellum, spinal cord, and peripheral nerves. |
| Alternative Names | Spinocerebellar degeneration |
| Causes, incidence, and risk factors | Friedreich ataxia is an autosomal recessive inherited polyneuropathy (damage to multiple nerves). The symptoms are caused by degeneration of structures in the cerebellum and spinal cord responsible for coordination, muscle movement, and some sensory functions. Symptoms generally begin in childhood before puberty. Early symptoms include an unsteady gait ( ataxia ), changes in speech ( dysarthria ), loss of reflexes, and jerky eye movements ( nystagmus ). Abnormal muscle control and tone lead to spinal changes and scoliosis or kyphoscoliosis may develop. Individuals with Friedreich's ataxia may also have hammer toe and high arches (pes cavus). Heart disease usually develops and may progress into heart failure . Death may result from heart failure or dysrhythmias that will not respond to treatment. Diabetes may develop in later stages of the disease in up to one third of patients. Friedreich ataxia results from lack of a specific protein (frataxin) in cells of the brain, nerves, heart and pancreas. The gene encoding this protein is susceptible to a particular kind of DNA mutation. That mutation is called triplet repeat expansion, and it is easily and reliably tested for in patient DNA from blood sample. Usually an affected person has inherited mutated (expanded) copies of the gene from both parents. That is to say, Friedreich ataxia is an autosomal recessive disease. |
| Symptoms | Unsteady gait and uncoordinated movements ( ataxia ) that gets progressively worse Jerky eye movements ( nystagmus ) Abnormal speech ( dysarthria )Loss of coordination and balance Frequent falls or falling more than usual Difficulty with control of the hands, clumsinessMuscle weakness (decreased muscle strength, independent of exercise )
Legs, arms, or other parts of the body May progress to paralysis Difficulty getting out of a chair or climbing stairs (hip or pelvis weakness ) Deformity of the spine or feet Shakiness, muscle tremors Sensory changes, decreased sensation , or numbnessDizziness Impaired speech or language, abnormal speech rhythm, difficulty speaking clearly Excessive thirst, urination or hunger (associated with diabetes)
Note: The intellect is normal.
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| Signs and tests | Progressive ataxia Absent deep tendon reflexes Distalmuscle weakness Decreased or lost vibratory sense Decreased positional sense Kyphoscoliosis Pes cavus Hammer toeHypertrophic cardiomyopathyCongestive heart failure Diabetes Degeneration of the back of the eye (retina) is a rare sign Tests may include: ECG Genetic testing for the frataxin gene X-ray of the chestX-ray of the spine Electrophysiologic studies An EMG ( electromyography ) Nerve conduction tests A muscle biopsyX-ray , CT scan, or MRI of the head |
| Treatment | There is no known cure for Friedreich's ataxia. Treatment is based on controlling symptoms and maintaining general health. As the disease may be associated with free radical damage to cells antioxidants such as Vitamin E and coenzyme Q10 are frequently prescribed. There is no systematic scientific evidence of the efficacy of these supplements. Research is ongoing on the use of a coenzyme Q10 derivative (idebonone) in Friedreich ataxia. In preliminary trials, it slowed the development of heart failure in a small number of patients. Physical activity is encouraged, and physical therapy may be beneficial. Safety must be considered when there is loss of balance and loss of sensation . Safety measures may include use of railings, walkers, or other appliances. The prevention of injury to a body part with decreased feeling may include: testing bath water to prevent burns , visual inspection of the body part to check for injuries, use of protective shoes, helmets, or other measures. |
| Support Groups | The Friedreich Ataxia Research Alliance (FARA) is an excellent source of information on this disease. |
| Expectations (prognosis) | Wheelchair confinement by young adulthood Heart failure Up to one third of patients develop diabetes that is treated in the typical fashion of all diabetes Death as a result of untreatable heart failure |
| Complications | Repeated or unnoticed injury Progressive disability Heart failure |
| Calling your health care provider | Call your health care provider if muscle weakness , numbness , loss of coordination , loss of reflexes, or other symptoms of Friedreich's ataxia occur (particularly if there is a family history of the disorder). |
| Prevention | Genetic counseling and testing are recommended for prospective parents with a family history of Friedreich ataxia . |
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