Down's syndrome – SD – Trysomyya 21

Down Syndrome (DS; Trisomy 21)

What is Down syndrome?

Down syndrome is a relatively common genetic disorder. Down syndrome causes birth defects, medical problems, and some degree of mental retardation.

Causes of Down Syndrome

Chromosomes contain genetic information about the structure of the body. Их количество в организме – 23 vapor. Down syndrome is a problem with the 21st pair of chromosomes. IN 21 there is an extra chromosome genetic material, which can cause disease following forms:

• The appearance of an extra chromosome (trysomyya) – этот тип синдрома Дауна называется трисомия 21. The disease is the result of an error in cell division in the egg or sperm;
• Появление дополнительной хромосомы в некоторых типах клеток – этот тип заболевания называется мозаичный синдром Дауна;
• Часть хромосомы разрывается и затем присоединяется к другой хромосоме – этот тип называется робертсоновская транслокация (Family Down Syndrome). Approximately one third of people inherit from their parents translocation.

Risk factors for Down syndrome

Factors, that may increase the risk of Down's syndrome include:

• Genetics: if one parent is a carrier of the translocation Down syndrome, there is an increased risk of the disease in a child;
• Age: the likelihood of having a baby with Down syndrome increases in women after 35 years;
• Paul: with Down syndrome are born more boys, than girls;
• The birth of a previous child with Down syndrome.

Symptoms of Down syndrome

Babies, born with Down syndrome may have some or all of the following physical symptoms:

• Flat facial features, slightly depressed nasal bridge and a small nose;
• Slanting eyes, small skin folds on the inner corner of the eye;
• Short neck with loose skin;
• The ears are of irregular shape and / or low-set;
• White spots on the colored part of the eye;
• The only fold of skin on the palms;
• Excess flexibility in joints;
• Problems with vision and hearing;
• Large and protruding tongue;
• The large distance between the big and second toe.

The degree of medical problems and intellectual disability is different for each person. People with Down syndrome may be congenital or acquired health problems:

• Vision problems;
• Hearing loss;
• Heart defects;
• Acute leukemia;
• Frequent ear infections;
• Instability of the bone in the upper part of the neck, It may lead to compression and spinal cord injury;
• Gastro-intestinal obstruction;
• Hirschsprung's disease, celiac disease;
• Sleeping problems, such as blocking the airway during sleep, daytime sleepiness, Disturbed sleep;
• Increased incidence of dementia in the elderly;
• Defects in the urinary system;
• High blood pressure in the lungs;
• Convulsions;
• Insufficient activity of the thyroid gland;
• Slow growth;
• Sick child begins to sit late, walk and go to the toilet on their own;
• Problems with speech;
• Obesity;
• Emotional problems.

Most of these problems are treatable . The average life expectancy of persons, born with Down syndrome about 55 years.

Diagnosis of Down Syndrome

Doctor, usually, after birth can determine the presence of his Down syndrome. If you suspect the presence of Down syndrome blood test is appointed, to confirm it.

Down syndrome can also be diagnosed before birth. There are screening tests and diagnostic tests for the detection of chromosome abnormalities before birth.

Screening tests for Down's syndrome

The screening test is performed, to assess the risk of having a child with Down syndrome. The doctor will use the results of various blood and mother's age, to assess the risk. Blood tests may include:

• Тройной скрининг – Альфа-фетопротеин, beta-subunit of human chorionic gonadotropin (beta-HCG), unconjugated (free) theelol (SE);
• Four-factor analysis of the mother's blood;
• Cell-free fetal DNA testing;

Screening can be done already at the 11 week of pregnancy. It also may include ultrasound and blood screening.

A small number of women screened can give false-positive results. It means, the test shows the presence of Down syndrome, but in fact it is not.

Diagnostic tests for Down's syndrome

Diagnostic tests show, whether the fetus has Down Syndrome actually. These tests include:

• Биопсия хориона – обычно выполняется в период от 10 to 12 weeks;
• Амниоцентез – обычно выполняется в период от 12 to 20 weeks of pregnancy;
• Percutaneous umbilical cord blood research (cordocentesis) – обычно проводится после 20 week of pregnancy.

These tests are accurate about 98-99%. Each test requires the selection of a small piece of placenta tissue or umbilical cord. Diagnostic testing methods pose a small risk of miscarriage.

Treatment of Down Syndrome

Down syndrome can not be cured, because it is a genetic disorder.

Some newborns, perhaps, need surgery to eliminate the serious health problems, such as heart defects.

Treatment may be needed for serious health problems or developmental delay. Specific therapies to help children with Down syndrome reach their full potential. Most people with the condition can actively participate in society. Some people with Down syndrome live in the family, some live with friends, and some live on their own.

Caring for a baby with Down syndrome

Children with Down syndrome may need more time to eat. A child with Down syndrome will also start to talk, walk and talk, later, than normal children.

Teaching a child with Down syndrome

For children with Down syndrome there:

• School Programs, designed to meet the special needs of the child;
• Programs teaching children in ordinary schools with additional support as needed.

Rehabilitation treatment of patients with Down syndrome

Speech, Physical and occupational therapy may improve the chances of a child. Therapy can help to improve speech, walking and daily living skills.

Social support for patients with Down syndrome

Professional support helps a family cope with caring for a child with congenital malformations and mental retardation. The psychiatrist will help in the management of emotional problems.

Prevention of Down syndrome

There are no guidelines for the prevention of Down syndrome. If you are concerned about having a child with Down syndrome, consult with a genetic counselor, before becoming pregnant.