Tay-Sachs syndrome

People with the Tay-Sachs syndrome have a rare genetic disorder. They slowly regress as the disease leads to a comatose state accompanied by loss of skill, seizures, and paralysis. In the terminal stages, patients lose consciousness and die.

What is Tay-Sachs Syndrome?

Tay-Sachs syndrome is inherited as an autosomal recessive trait. Autosomal recessive inheritance means that a person will only become ill if they have two copies of the corresponding recessive gene.
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Children with the Tay-Sachs syndrome born have no future, because this disease is incurable and invariably fatal. The name for this disease goes back to the American neurologist Bernhard Sachs (1858 to 1944) and the British ophthalmologist Warren Tay (1853 to 1927), who first described this hereditary fat storage disease. It occurs in children between the ages of three and seven months.

This fatal disease belongs to the group of hereditary metabolic diseases (gangliosidoses), which are also known as lysosomal storage diseases.Lysosomes are small cell organelles that have a multitude of different tasks in the human organism. Put simply, they act as organelles for “waste disposal”.

causes

In their capacity as small cell organelles, lyososomes contain a large number of enzymes (hydrolases) which are responsible for the orderly breakdown of carbohydrates, lipids, proteins (RNA, DNA) and defective cell components. They act as a catalyst. They fulfill certain defense functions, as they work together with the immune system and are responsible for the disposal of foreign pollutants and bacteria.

If a child suffers from lysosomal storage disease, their organism does not process certain substances as intended due to an enzyme deficiency. These are deposited in the lysosomes instead of being processed and excreted. Children with Tay-Sachs syndrome suffer from a deficiency in the enzyme hexoseaminidase A. This converts or breaks down sphingolipids, causing a pathological accumulation of lipids mainly in the brain.

Sphingolipids are a group of lipids that are involved in the construction of cell membranes. The lipids consist of fatty acids in combination (esterified) with the substance sphingosine (alcohol). These accumulations of fat cause neurons (nerve cells) to die. Tay-Sachs syndrome is therefore a neurodegenerative disease. The disease shows up early, the first symptoms usually appear from the third month of life.

These include increasing muscle weakness, a cherry-red spot in the back of the eye (macula), psychomotor degradation with loss of the ability to sit and stand, startle reactions to sound stimuli, blindness and deafness, paresis, spasticity, cramps, doll-like face with transparent skin, long and fine eyelashes Hair.

Symptoms, ailments & signs

Tay-Sachs syndrome is inherited as an autosomal recessive trait. Autosomal recessive inheritance means that a person will only become ill if they have two copies of the corresponding recessive gene. A person is called a carrier if he has only one copy of the recessive gene. Although these carriers have the pathological gene, this does not lead to the onset of the disease.

Because carriers have no symptoms and are just as healthy as other people, many of them do not know that they are carrying this gene. In many cases, this sponsorship only comes to light during the prenatal diagnosis or when the child is diagnosed with Tay-Sachs syndrome based on the symptoms. In the case of sexual reproduction, the gametes of men and women combine in the form of sperm, egg, and sex cells. This creates two sets of chromosomes that are passed on from each parent.

Each gene is present twice. How pronounced the genetically determined characteristics are in the child is determined equally by mother and father. Both genes of a certain trait are in the same place on the homologous chromosomes. If there is a genetic identity, the person with this gene is referred to as homozygous. If, on the other hand, the gene is present in two different variants (alleles), the person is referred to as heterozygous (mixed-breed). A dominant allele is present if one of the two alleles prevails over the other in terms of the characteristic expression.

The suppressed variant of the allele does not prevail and takes a back seat to the dominant one. Because of this, it is called recessive. The recessive allele (trait) only appears in the case of pure inheritance, in the homozygous state. In the case of recessive disease, both allele variants of the corresponding gene are mutated. This mutation leads to the development of the disease phenotype.

Diagnosis & course of disease

Healthy carriers of this recessive gene can be diagnosed through a blood test. If both parents inherit a healthy and a diseased gene, there is a 25 percent chance that their child will develop Tay-Sachs syndrome.

An examination of the amniotic fluid can also provide information about whether or not there is a risk. The disease leads to changes in the nerve tissue and multiple complaints, the loss of skills such as hearing, seeing, speaking, sitting and standing, and vomiting from the age of 16 months.

Complications

In most cases with Tay-Sachs syndrome, the patient dies. This cannot be completely prevented, but only slowed down. For this reason, parents and relatives in particular suffer from severe psychological complaints with this syndrome, which can also lead to depression.

Affected children lose consciousness with this disease and continue to suffer from a comatose condition. You are usually not responsive and are in a deep sleep. The development of the child also slows down due to the syndrome, so that the learned skills are lost again. This can lead to seizures or paralysis all over the body, so that the children depend on permanent treatment in their lives.

The affected children often suffer from pneumonia and other respiratory problems due to Tay-Sachs syndrome. Although these can be treated, the syndrome significantly limits the life expectancy of those affected. It is also not possible to prevent this disease. In many cases, the parents are dependent on psychological treatment.

When should you go to the doctor?

With Tay-Sachs syndrome, the person affected depends on a medical examination. This is the only way to avoid further complaints or complications, as this syndrome cannot heal itself. If Tay-Sachs syndrome is left untreated or is discovered late, it can, in the worst case, lead to death. Therefore, a doctor should be contacted at the first symptoms of Tay-Sachs syndrome. The doctor should then be consulted if the person concerned is permanently suffering from various types of inflammation. In most cases, the patient's lungs are affected, and inflammation of the lungs is common. These complaints occur even in small children. Therefore, if inflammation of the lungs occurs very frequently, a doctor must be contacted.

As a rule, Tay-Sachs syndrome can be diagnosed by a pediatrician or a general practitioner. However, despite treatment, the life expectancy of the person affected is significantly reduced. Therefore, parents and relatives should consult a psychologist in the case of Tay-Sachs syndrome so that depression or other psychological disorders do not occur.

Therapy & Treatment

The sick children usually die between the first and fourth year of life due to recurring pneumonia. So far there are no treatment options in the sense that the sick children can be cured. They become noticeable during the first year of life, after which the disease progresses inexorably. The life expectancy of the affected children is four years.

prevention

Since the disease is inherited in an autosomal recessive manner, there is no prevention in the clinical sense. Medicine is researching the molecular biological and biochemical causes of this disease in order to find a therapy option in the future.

Aftercare

Tay-Sachs syndrome can only be treated symptomatically so far. Follow-up care focuses on the individual complaints and psychological support for relatives and the patient. The psychomotor degradation must be strictly controlled. In the first few years of the disease, the muscular complaints can be partially counteracted by physiotherapy.

The patients always need drug treatment. The administration of drugs is checked as part of the aftercare. Since the disease is progressive, regular medication adjustments are required. In the latter stages of the disease, the patient can be transferred to a hospice.

This is followed by psychological support for the relatives and usually includes several discussions with a suitable therapist. The extent of the psychological follow-up is individual from case to case. Tay-Sachs syndrome is always fatal, which is why patients must be informed about their prospects of recovery at an early stage.

The sick people mostly also need support in everyday life. As part of the aftercare, the measures can be checked and adjusted if necessary. Again, due to the progressive progression of the disease, regular reassessment is necessary. Follow-up care is usually carried out by the family doctor and various specialists.

You can do that yourself

Tay-Sachs syndrome can only be treated symptomatically so far. It is important to counteract the increasing muscle weakness through physiotherapy and physiotherapy. The psychomotor degradation must be compensated for in the long term by aids such as crutches, wheelchairs, stair lifts and handicapped access. If symptoms such as hearing loss or blindness occur, the child needs ongoing support.

Since the disease progresses rapidly and leads to the death of the child by the age of three or four, further measures may have to be taken to support the parents during the child's illness phase and later during the mourning phase. In the last months of life, the most important measure is to enable the child to live as symptom-free as possible. In addition, it is always necessary to continue treating the symptoms.

After the child dies, trauma therapy can be useful. A visit to a self-help group or therapeutic treatment is ideal for coping with grief. It may also be necessary to take medication such as sedatives or antidepressants, the intake of which should be monitored by a doctor. The association “Hand in Hand gegen Tay-Sachs” provides those affected with additional contact points and tips on how to deal with Tay-Sachs syndrome.