Friedreich's ataxia

• What is Friedreich ataxia
• Statistics on Friedreich ataxia
• Risk Factors for Friedreich ataxia
• Progression of Friedreich ataxia
• Symptoms of Friedreich ataxia
• Clinical Examination of Friedreich ataxia
• How is Friedreich ataxia Diagnosed?
• Prognosis of Friedreich ataxia
• How is Friedreich ataxia Treated?
• Friedreich ataxia References

What is Friedreich ataxia

Friedreich ataxia is a disease of the central nervous system.
The nervous system in the body can be divided into 2 categories: the central nervous system and the peripheral nervous system.
The peripheral nerves make up a vast network that transmits impulses from the brain and spinal cord (the central nervous system) to every other part of the body. Peripheral nerves also send sensory information back to the brain and spinal cord.
Peripheral neuropathies refer to a diverse group of diseases affecting the motor, sensory and autonomic nerves lying outside the central nervous system (i.e. the spinal cord and the brain). This can cause a wide variety of symptoms, such as weakness, numbness or sensitivity to touch.
Friedreich ataxia affects the spinal cord and the cerebellum (the part of the brain that controls coordination of movement), hence termed spinocerebellar disorder. However, other parts of the body can be affected as well, such as the peripheral nerve, heart, and pancreas.

Statistics on Friedreich ataxia

Friedreich ataxia is a rare disease. It affects 1-2 per 100,000 population in the US and worldwide. Although rare, it makes up half of all the hereditary ataxic disorders. Hereditary means there is a genetic defect leading to formation of disease; ataxic means loss of coordination in movement.

Risk Factors for Friedreich ataxia

Friedreich ataxia is a genetic diseases transmitted by autosomal recessive pattern. Hence strong family history is a risk factor for this disease. Autosomal recessive means that both the parents must have the defect genes to pass on to the children, and if both parents do have the genes, each pregnancy bears 25% of transmitting the disease to the newborn.
Otherwise, there is no gender and ethnic race predilection worldwide.

Progression of Friedreich ataxia

Friedreich ataxia is caused by gene defects in chromosome 9. The net effect of this is nerve malfuction in the spinal cord, cerebellum (the part of the brain that coordinates movement), and peripheral nerves.
 

• Friedreich ataxia does not affect the intellectual function of the individuals.
• The symptoms of Friedreich ataxia may begin anytime between 5 to 15 years of age.
• Friedreich ataxia is associated with heart disease (hypertrophic cardiomyopathy) and pancreatic dysfunction leading to diabetes mellitus.
• The major causes of death are complications due to heart failure or loss of airway protection.
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  How is Friedreich ataxia Diagnosed?

  If a patient comes in and presents with peripheral neuropathy, it is important to rule out other treatable diseases. Hence a full physical examinationworkup will be done on the patient. These include looking at the blood function, kidney function, liver function, thyroid function, and the body’s iron, vitamins and electrolytes level.
  

  Prognosis of Friedreich ataxia

  Within 8-10 years following the onset of symptoms, the patient is usually unable to walk.
  Symptomatically, Friedreich ataxia is divided into 2 phases: ambulatory and non-ambulatory phase, characterized by the patient’s ability to walk. The length of ambulatory phase can be variable.
  95% of the patients reaches the non-ambulatory phases by the age of 45.
  Friedreich ataxia significantly reduces normal life expectancy of the patients. Although age of death is variable, reported mean ages have been in the mid 40s. Association of Friedreich ataxia and heart disease and diabetes significantly shortens the lifespan of the patient.
  

  How is Friedreich ataxia Treated?

  There is no cure for Friedreich ataxia. The treatment aims at symptomatic control and rehabilitation to optimize the outcome of disease.
  Foot care:
  Proper foot care reduces potential complications such as pressure ulcer and secondary infection. These include wearing custom-made shoes and leg braces. These are also important to reduce discomfort and optimize residual function.
  Physiotherapy:
  Physiotherapy and exercises are important to prevent disuse atrophy of the muscles. Moderate exercise is recommended to promote muscle strength and muscle endurance.
  Maintain function:
  Splinting, specially made household devices or surgery may be needed to maintain the function of the affected limbs, especially when the hands are affected.
  Psychosocial support:
  Many of the patients feel depressed and may need psychological support. Other than the patient, the carers should be provided psychological counselling as well regarding the disease and the difficulties in caring the patient.
  Team approach:
  It is especially important to provide a multidisciplinary approach to patients because of multiorgan involvement. Different fields of medicine will work together to provide support for the patient. Occupational and physiotherapy should be provided to optimise the patient’s general function.
  Currently multiple antioxidants have been tested and are still under research regarding their efficacy in reducing the progression of Friedreich ataxia. These include idebenone (a free radical scavenger), coenzyme Q10, and vitamin E. Although they clinically decrease the markers of oxidative injury, whether this change is clinically significant remains elusive.
  

  Friedreich ataxia References

  [1] eMedicine: Friedreich Ataxia [online]. 2005. [Cited 2005 October 23rd]. Available from: URL: http://www.emedicine.com/orthoped/topic109.htm
  [2] Kasper D, et al. Harrison’s Principles of Internal Medicine. 16th ed. New York: McGraw-Hill; 2005.
  [3] Kumar V, et al. Robbins and Cotran Pathologic Basis of Disease. 7th ed. New York: WB Saunders Company; 2004.
  [4] Lodi, R, Hart, PE, Rajagopalan, B, et al. Antioxidant treatment improves in vivo cardiac and skeletal muscle bioenergetics in patients with Friedreich’s ataxia. Ann Neurol 2001; 49:590.
  [5] Schulz, JB, Dehmer, T, Schols, L, et al. Oxidative stress in patients with friedreich ataxia. Neurology 2000; 55:1719.
  [6] Up to Date: Friedreich Ataxia [online]. 2005. [Cited 2005 October 23rd]. Available from: URL: http://www.utdol.com/application/topic.asp?file=ped_neur/6520&type=A&selectedTitle=1~3