Amavrotic idiocy

Amavrotic idiocy is a rare progressive disease. It is characterized by a gradual decrease in vision to complete blindness and degradation of the intellect, until idiocy comes. As a result, the patient develops deep senility with a fatal outcome. The disease was first described by the doctor-ophthalmologist Tau more than 130 years ago. Tau noted a special transformation of the fundus. More than 500 cases of the disease have already been described.

[1], [2], [3], [4], [5], [6], [7], [8], [9], [10],

Epidemiology

The epidemiology of the disease marks a family nature. In families where there are patients with amavrotic idiocy, for the same reason, dangerous marriages are dangerous. Also at risk are people who are of Canadian-French or Jewish origin.

[11], [12], [13], [14], [15], [16], [17], [18],

Causes of the amavrotic idiocy

Despite the numerous data collected about the disease, now many questions about the causes, pathogenesis and even manifestations of amaurotic idiocy, scientists continue to seek answers.

There are suggestions that the disease has a hereditary nature. The type of inheritance is autosomal recessive. The cerebellum, occipital lobes of the cerebral hemispheres with severe consequences and complications for the whole organism are most often affected: atrophy of the optic nerves, nerve fibers can lose their shells, and the connections between nerve cells - disintegrate.

Most experts acknowledge that the clinical signs of the disease can be quite diverse and have a correlation with age in which the amaurotic idiocy began to develop in the patient.

In the course of the study of the causes of the disease, a certain pattern is noted: often the disease affects children from the same family, which is why the name "family amavrotic idiocy" is used. According to studies, the results that were published when the disease was only beginning to be studied, out of 64 cases of amaurotic idiocy 37 were found in 13 families (in each family there were 2-5 sick children). It is noteworthy that in such families the patients had absolutely healthy brothers and sisters. Nowadays, the recessive inheritance factor is of great importance in the development of the disease. Thus, it is possible to explain the incidence of cases in the same families. During the analysis of the heredity factor as the cause of amaurotic idiocy, one should not confine oneself to the presence of clinically expressed signs in the families of patients (both on the ascending and lateral lines), and take into account rudimentary, for example, characteristic deviations in the work of the visual apparatus (family choroiditis, retinal pigmentary degeneration etc.).

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Pathogenesis

The anatomical basis for the development of the disease is the specific disintegration of ganglionic cells, which appears as a consequence of a violation of lipid metabolism within the cell.

[23], [24], [25], [26], [27], [28], [29], [30]

Symptoms of the amavrotic idiocy

The first signs of a congenital form appear in the first days or weeks of life. The baby is born with hydrocephalus or microcephaly, suffers from convulsions, paralysis, impaired respiratory function. The baby dies after a few months.

[31], [32], [33], [34], [35], [36], [37],

Stages

Infantile form develops from 4-6 months. It is this form of amaurotic idiopathy that is inherent in the family. Vision rapidly falls: the baby can not fix the sight, does not observe the objects. On the fundus there is a so-called "cherry stone" - a reddish stain in the macular area, which is surrounded by a gray-white rim. Then optic nerves are atrophied, and the child completely loses the ability to see. Gradually, tentative, defensive reflexes are lost, as well as the ability to move. Patients react strongly to sound stimuli - they shudder from a low sound for a healthy person, there may be convulsions that arise due to increased muscle tone. In the final stage of the disease, general atrophy, depletion of the body and increased tone of all extensor muscles develop. The prognosis of the disease is also disappointing: the patient dies after one and a half or two after the onset of the disease.

Late children's form begins in 3-4 years. The progressing disease is interspersed with the stages of remission. The gradual loss of intelligence is accompanied by convulsions, coordination disorder, extrapyramidal disorders. This form is also characterized by atrophy of the optic nerve. Death occurs after 6-8 years from the beginning of the development of amavrotic idiocy.

The youthful form begins to appear 6-10 years. The amphetoric idiocy of Spilmeyer progresses not so fast. Changes in the eye fundus coincide with manifestations of pigmentary degeneration of the retina. The patient's vision gradually decreases, like the intellect. Violation of motor functions can manifest itself in different ways and not consistently: there are not very pronounced paralysis of the arms and legs, extrapyramidal and bulbar disorders. The disease leads to death in 10-25 years after the development of the first signs.

The late form arises very rarely and develops very slowly. The mental state of the patient changes (by the type of organic mental syndrome), there is atrophy of the optic nerves and pigmentary degeneration of the retina of the eye. The final stage is characterized by paralysis and epileptiform syndrome. The patient dies in 10 - 15 years from the time of the onset of the disease.

[38], [39], [40], [41], [42], [43], [44], [45],

Forms

There are four types of amaurotic idiocy:

• Tei-Saksa (striking at an early age);
• Yansky-Bilynovsky (manifested in children at a later age);
• Shpilmeier-Vogt (manifested in adolescents);
• Kufsa (the late form).

Some scientists distinguish separately and the congenital form of Norman-Wood.

Each type of disease has its own set of clinical manifestations, but all of them are united by common causes, clinical picture, anatomical base and pathogenesis.

[46], [47], [48], [49], [50], [51], [52], [53], [54]

Diagnostics of the amavrotic idiocy

Amavrotic idiocy are caused by a disturbance in lipid metabolism, as a result of which an intermediate product of lipid metabolism is deposited in various cells of the body - sphingomyelin. The location and composition of the deposits contribute to the development of a specific clinical picture of the disease.

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Differential diagnosis

Differential diagnosis of amaurotic idiocy is based on a special clinical picture and characteristic pathologies of the fundus.

The early form has similar symptoms with the disease of Landing - a type of mucopolysaccharidosis. Lunding's disease develops from the first months after birth and leads to death 2-3 years later. "Cherry stone" on the fundus appears in 1/5 of the cases, degenerative changes in the retina and perverted perception of sounds (hypercussion) for it are almost not characteristic, but there is a simultaneous increase in the spleen and liver, mental disorders and movement disorders.

The juvenile form sometimes overlaps with the manifestations of the Lawrence-Moon-Biddle syndrome. To differentiate these diseases, it is necessary to pay attention to their other manifestations. For the Lawrence-Moon-Biddle syndrome, a rapid set of excess weight, deformity of the extremity characterized by the presence of additional fingers on the hands or feet, marked vegetative-trophic disorders and the absence of disturbances in the motor function are characteristic.

The variety of symptoms of the late form of amavrotic idiocy complicates the diagnosis during life. Its manifestations are similar to Friedreich's ataxia, multiple sclerosis, Alzheimer's disease, Pick's disease, progressive paralysis and even schizophrenia.

Some authors insist that the diagnosis of this disease, especially when the clinical manifestations are lubricated, can be reliably established only after death, based on an analysis of the histological deviations of the nervous system.

Treatment of the amavrotic idiocy

Rational and effective treatment does not exist. In our time, therapy for amaurotic idiocy is aimed solely at alleviating the symptoms. Used sedative drugs, nootropic drugs, drugs that relieve cramps and medications fortifying effect.

To activate blood circulation and metabolic processes of the brain, glycine, elcar, cerebrolysin, glutamic acid, pantogam are prescribed.

To remove the convulsive syndrome, diphenine or carmazepine is prescribed.

A positive result can be the use of tissue extracts, blood or plasma transfusion.

Prevention

The lack of effective therapy for amaurotic idiocy makes one pay close attention to prevention. Already there are methods that allow us to identify heterozygous carriers of the pathological gene and how to diagnose amaurotic idiocy during fetal gestation. Antenatal diagnosis of the disease consists in the analysis of the activity of hexosaminidase A in the amniotic fluid. If a decreased activity of the enzyme is found, it is recommended to terminate the pregnancy. Parents of a sick child are advised to stop further childbearing.

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