Hereditary cerebellar ataxia of Pierre-Marie
Hereditary cerebellar ataxia of Pierre-Marie is a genetic and familial disease caused by a progressive cerebellar disorder, burdened with damage to the pyramidal pathways. It is characterized by an increased tendon reflex, chanted speech, an imbalance in coordination of movements, impaired vision and oculomotor motility. The nature of inheritance is autosomal dominant. The mutant gene has a high population: generation skipping is rare.
The content of the article:
Causes and course of Pierre-Marie ataxia
Symptoms of Pierre-Marie ataxia
Differential diagnosis of Pierre-Marie ataxia
Diagnosis of Pierre-Marie ataxia
Treatment and prognosis of Pierre-Marie ataxia
Hereditary cerebellar ataxia of Pierre-Marie
Among hereditary diseases, spinocerebellar ataxias are in second place in terms of incidence after neuromuscular pathologies. According to statistical data, Pierre-Marie cerebellar ataxia affects 1 person per 200 thousand of the population.
Genetic disorder in childhood and adolescence is asymptomatic and manifests itself from the third decade of life.
Causes and course of Pierre-Marie ataxia
The damage to the functions of the cerebellum is caused by genetic pathology according to the autosomal dominant type of inheritance. For the development of ataxia, a genetic disorder inherited from one parent is enough.
The cerebellum is the main coordination center that performs motor tasks. Its hemispheres are responsible for the consistency of movements, and the cerebellar worm is responsible for stability and balance.
Pathoanatomic signs of the disease are expressed by hypoplasia of the cerebellum, a decrease in the lower olives and exhaustion of the varolian bridge. Against this background, as a rule, degeneration of the spinocerebral pathways occurs, destruction of cells of the cerebellar cortex and nuclei, degenerative disorders of the medulla oblongata and in the nuclei of the bridge of the brain.
Depending on the concentration of cerebellar lesion, ataxia is divided into dynamic and static-locomotor. In the first case, pathological disorders are found in the hemispheres, which causes desynchronization of muscle rhythms (dysmetry, chanted speech, involuntary trembling of the trunk, head, limbs, etc.) With a static-locomotor form, the worm is affected, which causes a disorder of gait, stability and balance.
Despite the innate nature, Pierre-Marie’s ataxia manifests from the age of 20 and older. Infectious diseases (salmonellosis, zoonotic infection, bacterial pneumonia, typhoid or typhus, pyelonephritis, meningitis, etc.) are the provoking factors. As exogenous causes, traumatic brain injury, fracture of the pelvic bones or chest, deep burns and intoxication of various nature can serve.
Hereditary cerebellar pathology is characterized by continuously progressive manifestations. Symptomatic therapy does not provide periods of remission. External pathogenic factors in the form of various diseases worsen the patient’s condition. In the future, the severe condition passes and the typical symptom complex of cerebellar pathology returns.
Symptoms of Pierre-Marie ataxia
The main sign of a hereditary disease will be neuromuscular motor disorders, which are not limited to a particular muscle group or specific movements.
Cerebellar ataxia is distinguished by characteristic symptoms:
gait disorder;
static disorder;
tremor of limbs and body;
muscle twitching;
involuntary frequent oscillatory eye movements;
slow speech;
change in handwriting towards a significant increase in letters;
decreased muscle tone.
Ataxia begins to develop with a violation in gait: the patient moves swaying. Sometimes the first symptoms will be lumbar lumbar region. Then the pathology affects the hands, their trembling is noted.
With Pierre-Marie’s disease, paresis of the extremities can be observed, against which tendon reflexes are increased. Often, the flexor and extensor pyramidal reflexes of the feet are recorded in the patient. Cerebral symptoms are quite common: drooping of the upper eyelid (ptosis), difficult convergence of the eyes, optic nerve atrophy.
50% of patients have mental and mental disorders: dementia, oligophrenia, depression.
Differential diagnosis of Pierre-Marie ataxia
Scrupulous collection of information on the genetic morbidity of the closest relatives and features of the clinical picture is of no small importance in the diagnosis.
Diagnostics involves laboratory and instrumental studies:
Electroencephalography (EEG). Detects diffuse delta/theta activity and alpha rhythm attenuation;
Electromyography. Reveals axonal-demyelinating disorder of peripheral nerve fibers;
Magnetic resonance imaging. Records morphological changes in the structures of the spinal cord and brain;
DNA test. Determines the genetic nature of ataxia;
Laboratory tests. They allow you to recognize a violation of amino acid metabolism.
A single case in the family of cerebellar ataxia requires a deeper examination and differential diagnosis. In addition to the above-mentioned diseases that have a symptom complex of ataxia, an examination is carried out to exclude a neoplasm of the cerebellum, abscess or hematoma of the brain, cerebellitis and hydrocephalus.
In case of ophthalmic disorders, an examination by an appropriate specialist is required.
To confirm the preliminary diagnosis of familial ataxia, a geneticist’s consultation is necessary.
Diagnosis of Pierre-Marie ataxia
The symptom complex of cerebellar ataxia is identical to the clinical picture of Friedreich’s hereditary ataxia. Therefore, difficulties arise when making a diagnosis.
The main difference is the type of inheritance. Dominant inheritance is characteristic of Pierre-Marie cerebellar disease. Recessive appearance is characteristic of Friedreich’s ataxia. The age at which the symptoms of the disease appeared is taken into account. Earlier manifestation is characteristic of the autosomal recessive nature of the disease.
A neurologist examines changes in tendon reflexes, which are increased in the cerebellar form of ataxia and lowered in Friedreich’s disease. In addition, Pierre-Marie’s ataxia is not characterized by bone deformities and loss of sensitivity.
It is very difficult to differentiate multiple sclerosis and cerebellar ataxia. Both diseases are characterized by pyramidal defects of the feet, oculomotor disorders, as well as neuromuscular motor disorders. However, with multiple sclerosis, as opposed to ataxia, periods of remission are possible. In addition, a distinctive feature of sclerosis is deep paraparesis and more pronounced pelvic disorders.
Treatment and prognosis of Pierre-Marie ataxia
The leading doctor in this case is a neurologist. He develops a scheme of conservative therapy, which is aimed at leveling the symptoms and includes:
A restorative drug complex. Drugs that suppress the enzyme cholinesterase (disaggregants), prevent damage to brain neurons (neuroprotectors), vitamins PP, B and C are prescribed;
Physical therapy, kinesiotherapy are the main rehabilitation measures. The task of training is to treat movement, strengthen muscles and weaken the symptom of discoordination. With statistical cerebellar ataxia, exercises are selected to train balance. For dynamic ataxia, a training complex is being developed that increases the consistency and accuracy of movements.
Physical therapy. It is carried out in order to prevent limb contracture, muscle atrophy, gait correction, improve coordination, and support general physical form;
Massage, manual and reflexology. It is carried out to improve metabolic processes.
The prognosis of Pierre-Marie’s hereditary ataxia is unfavorable for work activity. Symptoms progress throughout life, the ability to work decreases, and mental disorders worsen. The patient is disabled.
Nevertheless, provided that symptomatic therapy is constantly performed and a gentle regime is observed, the prognosis for life is good.
