Friedreich's disease (Friedreich's ataxia) is a genetic disease in which ataxia is the predominant symptom. Friedreich's disease may show up in childhood, which is even worse - the symptoms worsen with age, and eventually the patient becomes unable to move independently. The worst part, however, is that Friedreich's disease is currently incurable.

Friedreich's disease( Friedreich's ataxia ) is the most common disease in which ataxia is caused by genetic defects. It is estimated that the disease affects one in 50,000 people in the population. However, the prevalence of the mutated gene carrier is much greater - according to statistics, one in 110 people is the carrier of incorrect genetic information. The disease occurs with a similar frequency in women and men.

The first symptoms of Friedreich's disease appear early, even between the age of 5 and 15 of the patient. In the vast majority of patients, disorders begin before the age of 20, but there are forms of Friedreich's ataxia in which the first symptoms appear only in the second or third decade of life.

Friedreich's disease: causes

The underlying cause of Friedreich's disease are mutations in the FXN gene, located on chromosome 9. The disease is inherited in an autosomal recessive manner, which means that you need to have two copies of the abnormal gene to get the disease (carriers of one copy of the mutated gene do not have any deviations).
The problem with this condition is the excessive number of GAA (guanosine-adenine-adenine) triplicate repeats. This specific excess of genetic information leads to dysfunction of the protein - frataxin, encoded by the FXN gene. This substance is normally found in the mitochondria and is associated with the transformation of iron. The reduction in frataxin associated with the mutation leads to iron deposits in the mitochondria that can negatively affect the function of a wide variety of cellular proteins.
This relationship is considered to be one of the causes of organ damage occurring in patients with Friedreich's disease, but it is probably not the only mechanism of the disorders - the exact pathogenesis of the disease is stillremains unclear.

Friedreich's disease: symptoms

As one of the unit names suggests, ataxia is a major problem in Friedreich's disease. It is caused by progressive damage to the structures of the nervous system, such as e.g. dorsal nerve root ganglia, spinal-cerebellar and cortico-spinal pathways. Friedreich's disease also causes damage to the myelin sheaths of peripheral nerves.
The neurological symptoms of Friedreich's ataxia, caused by the above-mentioned pathologies, include:

  • progressive weakening of muscle strength (mainly in the lower limbs, but also in the upper limbs)
  • motor coordination disorders, which may be accompanied by frequent falls
  • sensory disorders (visual and hearing impairment)
  • impairment of some types of feeling (e.g. vibration)
  • slurred speech

Friedreich's disease is manifested primarily by ailments from the nervous system, unfortunately they are not the only problems of patients with this condition. Other problems encountered by people with this disease are:

  • cardiological problems (e.g. atrial fibrillation, impulse conduction disturbances within the heart muscle or cardiomyopathy)
  • lateral curvature of the spine (scoliosis)
  • abnormal, excessive hollowing of the feet
  • carbohydrate metabolism disorders (in the form of impaired glucose tolerance, and sometimes even diabetes)
Worth knowing

Ataxia is a condition in which motor coordination is disturbed to various degrees. It may lead to conditions experienced by the patient during his life (such as, for example, a stroke), but the cause of ataxia may also be an inherited genetic disorder existing in a person from birth. An example of the latter situation is Friedreich's disease.

Friedreich's disease: diagnosis

The existence of Friedreich's disease in a patient can be suspected on the basis of a very early (even in childhood) appearance of neurological disorders. Specific deviations can already be found in the neurological examination carried out by the doctor, they may be:

  • dysmetria
  • dyzartria
  • nystagmus
  • abolition of tendon reflexes
  • decrease in muscle strength

In order to confirm the diagnosis, genetic tests are performed, in which it is possible to identify mutations leading to Friedreich's disease. Research is also used throughout the diagnostic processimaging, the technique of choice in this case is magnetic resonance imaging, which allows to visualize the degree of degeneration of the structures of the nervous system.

Friedreich's disease: treatment

Friedreich's ataxia is an incurable disease - so far it has not been possible to develop a drug that would stop the progressive degeneration of the structures of the nervous system. Attempts are being made to implement the treatment of the disease with inhibitors of histone deacetylases or interferon, however, these therapies are only at the stage of clinical trials.
For the above-mentioned reason, in people with Friedreich's disease, the most important effect is maximizing the efficiency of patients. Various forms of rehabilitation can be used with them, including both various muscle exercises and (in the case of dysarthria patients) speech exercises.
The remaining problems of patients with Friedreich's ataxia are subject to specific treatment - this is the case, for example, in the case of scoliosis, which can be treated surgically by stabilizing the spine. In the case of cardiological diseases, pharmacological treatment is primarily used, and specific therapy can also be implemented in patients struggling with carbohydrate metabolism disorders.

Friedreich's disease: prognosis

The prognosis of patients with Friedreich's ataxia is unfortunately not very good - even more than 95% of patients are forced to use a wheelchair around the age of 45. The disease leads not only to loss of independence, but also to premature death - in one of the conducted studies it was determined that the average age of patients with Freidrech's disease at the time of death is around 38 years.

About the authorBow. Tomasz NęckiA graduate of medicine at the Medical University of Poznań. An admirer of the Polish sea (most willingly strolling along its shores with headphones in his ears), cats and books. In working with patients, he focuses on always listening to them and spending as much time as they need.

Category:

Genetic diseases