Ataxia is a disease manifested in discoordination of movement, impaired motor skills with a slight decrease in strength in the limbs. One species is Friedreich's family ataxia, the most common form of hereditary ataxia. It occurs in 2 to 7 people out of 100,000.
This disease most often begins in childhood, on the 1-2nd decade of life (although there are times when it is detected after 20 years). Typically, ataxia affects several family members - brothers, sisters, and in most cases it occurs in families with consanguineous marriage. Symptoms appear imperceptibly, the disease progresses slowly, lasts for decades, and without medical assistance causes significant discomfort.
Signs of the disease
The main sign of Friedreich's ataxia is the patient’s hesitant gait. He walks awkwardly, puts his legs wide and swings swiftly from the center to the sides. When the disease progresses, the arms, as well as the muscles of the chest and face are impaired. Mimicry changes, speech slows down, becomes jerky. Tendon and periosteal reflexes decrease or disappear (first on the legs, then spread to the arms). Hearing is often reduced. Scoliosis progresses.
Causes of the disease
This type of ataxia is hereditary, of a chronic type, of a progressive nature. It refers to spinocerebellar ataxia, which is a group of similar symptoms of diseases caused by damage to the cerebellum, brain stem, spinal cord and spinal nerves, which often interferes with the correct diagnosis. However, among cerebellar ataxia, Friedreich's disease is characterized by the presence of a recessive form, while other species are transmitted in an autosomal dominant manner. That is, a sick child is born in a couple where the parents are carriers of the pathogen, but are clinically healthy.
This ataxia is manifested by combined degeneration of the lateral and posterior columns of the spinal cord, caused by an enzymatic-chemical anomaly of an obscure nature, inherited. With the disease, the Gaulle bundles, the cells of the Clark pillars and the posterior spinocerebellar pathway are affected.
"Medical history"
Friedreich's disease was isolated in an independent form more than 100 years ago by the German professor of medicine N. Friedreich. Since the 1860s, the disease has been actively studied. After the suggestion was made in 1982 that mitochondrial disorders were the cause of this ataxia. As a result, instead of the generally accepted name “Friedreich's ataxia”, the term “Friedreich’s disease” was proposed, which more accurately reflects the multiplicity of manifestations of diseases - both neurological and extra-neural.
Neurological symptoms
If the patient has Friedreich's ataxia, the symptoms that are most often noticed first are awkwardness and insecurity when walking, in particular in the dark, staggering, and stumbling. Then discoordination of the upper extremities, weakness of the muscles of the legs join this symptom. At the beginning of the disease, a change in handwriting, dysarthria is possible, in the character of explosiveness, staccato is observed.
Oppression of reflexes (tendon and supracranial) can be noted both during the manifestation of other symptoms, and long before them. With the progression of ataxia, total areflexia can usually be observed. An important symptom is the Babinsky symptom, muscle hypotension, in the future, the leg muscles become weaker, atrophy.
Extraneural manifestations and other symptoms of ataxia
Friedreich disease is characterized by skeletal deformities. Patients are prone to scoliosis, kyphoscoliosis, deformities of the fingers and toes. The so-called Friedreich foot (or Friedreich foot) is a feature in Friedreich's ataxia disease. Photos of such feet give a clear understanding that such a deformation is not characteristic of a healthy body: the fingers are overbent in the main phalanges and bent in the interphalangeal joints with a high concave arch of the foot. The same change can occur with brushes.
Patients are also prone to endocrine diseases: they often have disorders such as diabetes mellitus, ovarian dysfunction, infantilism, hypogonadism, etc. Cataracts are possible from the organs of vision.
If Friedreich's ataxia is diagnosed , then in 90 percent of cases it will be accompanied by heart damage, the development of progressive cardiomyopathy, mainly hypertrophic. Patients complain of pain in the heart, palpitations, shortness of breath during physical exertion, etc. In almost 50 percent of patients, cardiomyopathy causes death.
In the late stage of the disease, patients have amyotrophy, paresis, and sensory disturbances in the hands. Possible hearing loss, atrophy of the optic nerves, nystagmus, sometimes the functions of the pelvic organs are impaired and the patient suffers from a delay or, conversely, urinary incontinence. Over time, patients lose their ability to walk and serve themselves without assistance. Nevertheless, the paralysis that arose with any form of ataxia, including Friedreich's disease, was not noted.
As for dementia, with a disease such as cerebral ataxia of Friedreich, there is no exact data on it yet: in adults, dementia occurs, it is described, in children it is extremely rare, as is mental retardation.
Complications of Ataxia
Friedreich's hereditary ataxia in most cases is complicated by chronic heart failure, as well as all types of respiratory failure. In addition, patients have a very high risk of recurring infectious diseases.
Friedreich ataxia diagnostic criteria
The main diagnostic criteria for the disease are indicated quite clearly:
- inheritance of the disease occurs on a recessive basis;
- the disease begins before the age of 25, more often in childhood;
- progressive ataxia;
- tendon areflexia, weakness and atrophy of the muscles of the legs, and later the arms;
- loss of deep sensitivity, first lower limbs, then upper;
- blurred speech;
- skeleton deformities;
- endocrine disorders;
- cardiomyopathy;
- cataract;
- atrophy of the spinal cord.
At the same time, DNA diagnostics confirm the presence of a defective gene.
Establishing diagnosis
When it comes to a disease such as Friedreich's ataxia, the diagnosis should include taking an anamnesis, conducting a full medical examination and studying the medical history of the patient and his family. During the examination, special attention is paid to problems with the nervous system, in particular poor balance, when the child’s gait and statics are examined, and the absence of reflexes and sensations in the joints. The patient is not able to touch the elbow with the elbow, misses with a finger test, and may suffer tremors with outstretched arms.
In laboratory studies, there is a violation of amino acid metabolism.
An electroencephalogram of the brain during Friedreich's ataxia detects diffuse delta and theta activity, a reduction in alpha rhythm. Electromyography reveals axonal-demyelinating lesions of the sensory fibers of the peripheral nerves.
Genetic testing is performed to detect a defective gene. Using DNA diagnostics, the possibility of pathogen inheritance by other children in the family is established. Comprehensive DNA diagnostics for the whole family can also be performed. In some cases, prenatal DNA diagnostics are necessary.
In the diagnosis and in the future after diagnosis, the patient is required to regularly take x-rays of the head, spine, chest. If necessary, computed and magnetic resonance imaging is prescribed. In this case, on an MRI of the brain, atrophy of the trunks of the spinal cord and brain, of the upper parts of the cerebellar worm can be noticed. An examination with an ECG and an echo EEG is also necessary.
Differential diagnosis
When making a diagnosis, it is necessary to differentiate Friedreich’s disease from multiple sclerosis, amyotrophy neural, familial paraplegia and other types of ataxia, primarily Louis-Bar disease, the second most common ataxia. Louis-Bard disease, or telangiectasia, also begins in childhood and is clinically different from Friedreich's disease by the presence of extensive dilatation of small vessels, the absence of skeletal abnormalities.
It is also necessary to distinguish the disease from Bassen-Kornzweig syndrome and ataxia caused by a deficiency of vitamin E. In this case, when diagnosing, it is necessary to determine the content of vitamin E in the blood, the presence / absence of acanthocytosis and examine its lipid spectrum.
During the diagnosis, it is necessary to exclude metabolic diseases with an autosomal recessive type of inheritance, accompanied by spin-cerebellar ataxia of other forms.
The difference between multiple sclerosis and Friedreich’s disease is the absence of tendon areflexia, with no muscle hypotension and amyotrophy. Also, with sclerosis, extra-neural manifestations are not observed, there are no changes in CT and MRI.
Ataxia treatment
Patients diagnosed with Friedreich's ataxia should receive treatment from a neurologist. To a greater extent, the treatment is symptomatic, aimed at the maximum removal of the manifestations of the disease. It includes restorative therapy, including the appointment of ATP, cerebrolysin, B vitamins, as well as anticholinesterase drugs. In addition, in the treatment of this ataxia, an important role is played by drugs with the function of maintaining mitochondria - such as succinic acid, riboflavin, vitamin E. Riboxin, cocarboxylase, etc. are prescribed to improve myocardial metabolism.
General strengthening treatment with vitamins is carried out. Treatment should be repeated periodically.
Since with the disease the main cause of pain is progressive scoliosis, patients are shown wearing an orthopedic corset. If the corset does not help, a number of surgical operations are performed (titanium rods are inserted into the spine to prevent further development of scoliosis).
All these measures are aimed at preserving the patient’s condition for as long as possible and stopping the progress of the disease.
Ataxia prognosis
The prognosis of such diseases is generally unfavorable. Neuropsychiatric disorders progress slowly, the duration of the disease varies very widely, but in most cases does not exceed 20 years in 63% of men (for women, the prognosis is more favorable - after the onset of the disease, almost 100% live longer than 20 years).
The causes of death are most often heart and lung failure, complications from infectious diseases. If the patient does not suffer from diabetes and heart disease, his life may last until advanced years, but such cases are quite rare. Nevertheless, due to symptomatic treatment, the quality and life expectancy of patients may increase.
Prevention
Prevention of Friedreich's disease is based on genetic counseling.
A physical and athletic complex is indicated for patients with ataxia, thanks to which muscles are strengthened and discoordination is reduced. Exercises should primarily be aimed at training balance and muscle strength. Exercise therapy and corrective exercises allow patients to be active for as long as possible, in addition, in this case, the development of cardiomyopathy is prevented.
In addition, patients can use auxiliary means to improve their quality of life - canes, walkers, strollers.
In nutrition, it is necessary to reduce the intake of carbohydrates to 10 g / kg, so as not to provoke an increase in the defect in energy metabolism.
It is also necessary to avoid infectious diseases, avoid injuries and intoxication.
One of the important factors in the prevention of disease is the prevention of hereditary transmission of ataxia. If possible, you should avoid giving birth to children if there have been cases of Friedreich's ataxia in the family, as well as marriage between relatives.