Down's disease after 50. Mikhailova m.s.

The article describes the characteristics of children with Down syndrome and methods for detecting genetic pathologies in the fetus during pregnancy.

Often, especially cheerful and good-natured people with slanted eyes and round faces evoke pity or misunderstanding among others. But few people know that people with Down syndrome are not only disabled people who need protection and sympathy, but, first of all, creative, comprehensively developed, talented individuals.

What does the word Down mean?

Down syndrome is named after the doctor John Down, who was the first to discover similarities in behavior, mental capabilities and expression of emotions in people with some common features of the structure of the skull and tongue. The disease officially received its name in 1965.

The doctor and scientist Down worked as a medical director at the Ersud Royal Asylum for the Insane since 1858. The goal of his activities was to prove that classes with mentally retarded children produce positive results. He became the founder of the Normansfield Development Center, created for children with genetic disorders.

IMPORTANT: Down children are also called Sunny children because of their positive thinking, love for all living things, ability to make friends, sympathize and empathize.

What is Down syndrome: symptoms, face, photos of newborns

Down syndrome is an abnormal genetic feature of the body that occurs when the number of chromosomes increases. Instead of 46 chromosomes, nature “endowed” these people with 47 chromosomes, namely, the 21st pair has an extra chromosome.

IMPORTANT: According to WHO statistics, 1 in 650 - 700 babies has Down syndrome. Moreover, the number of male and female children with this pathology is the same.

The incidence of Down births increases with the age of the mother, however, even 18-year-olds are not immune from the manifestation of this genetic disease in their children. After 33 years, a woman’s risk of giving birth to Down increases several times.

There are such forms of the syndrome:

• trisomy
• translocation
• mosaicism

Symptoms:

• the face and back of the head are unnaturally flat
• special eye shape
• peculiar skull shape
• wide skin folds in the upper eyelid area
• unnaturally small ears
• short limbs
• curvature of the little finger
• far back thumb
• deep fold “cutting” the palm across
• slow growth
• weak muscle tone
• poor coordination
• slurred speech
• weak mental abilities

IMPORTANT: Despite many physical characteristics, people with Down syndrome are cheerful, open, naive, cheerful, kind and affectionate. Many of them have a well-developed ear for music and a passion for art.

The face of a person with Down syndrome has four striking features:

• round and flat shape
• slanted eyes with additional folds above the eyelids at the top
• open mouth
• wide and at the same time small nose

How many chromosomes does a person with Down syndrome have?

Down syndrome is also called trisomy on chromosome 21. This means that downs inherit three instead of two 21 chromosomes. Usually two copies are inherited from the mother and one from the father. Thus, instead of 46 chromosomes, downs have 47 chromosomes, 3 of which are the 21st.

About 3% of downs do not inherit the entire 21st chromosome, but only some genes attached to the 14th chromosome. This phenomenon is called translocations.

Another 3% inherit the genes of chromosome 21 not in every cell, but only in some. This mosaic option. Often such people do not have clear signs of the syndrome, their intellectual and physical capabilities are not very limited. Signs of the mosaic type may be invisible to others.

Why are children born with Down syndrome: reasons

The only thing that increases the risk of having a Down is the age of his biological father and mother. The older the parents, the more likely it is that a child will be born with genetic disorders.

For woman"critical" age begins with 33-35 years, when the probability of having a Down increases to 1:30. For a man this danger is increasing after 42 years. This is due to the aging of the female body and the deterioration of sperm quality in men.

IMPORTANT: Smoking, alcoholism, drug addiction, and an antisocial lifestyle do not increase the likelihood of being born with Down. The appearance of this pathology is also not affected by ecology, ambient temperature or weather.

Also, the cause of giving birth to a child with Down syndrome is high among mothers with Down syndrome (about 50%). However, in most cases they experience spontaneous miscarriages in the early stages. Down men cannot have children.

Who gives birth to children with Down syndrome?

Children with Down syndrome can be born to completely healthy parents. If healthy parents have already given birth to one down child, then the probability of them having a second down child is approximately 1%.

The older the mother, the greater the likelihood of being born with Down:

• under 25 years old – 1:2000
• 25 years – 1:1250 – 1:1270
• 30 years – 1:1000
• 35 years 1:450
• 40 years – 1:150
• 45 years – 1:30 – 1:50

The likelihood of being born with Down syndrome is increased in those who are carriers of a genetic translocation. If the carrier is the mother, then this probability is 30%, the father is about 5%.

Down syndrome: signs during pregnancy

It is quite difficult to identify Down syndrome in a fetus in the early stages. One of the alarming signals is the detection on ultrasound of subcutaneous fluid in the back (collar) part of the neck at 11–13 weeks. However, this method is unreliable - in 20% of cases the result turns out to be false.

The results of a comprehensive examination are the most reliable. If, at the same 11–13 weeks, an ultrasound revealed a pathological thickening in the collar area and, in addition, the results of the blood serum test were positive, the pregnant woman is prescribed a “triple test” at a period of 16–18 weeks.

In cases where all these analyzes and tests indicate the presence of Down syndrome in the fetus, there is no doubt: 99 out of 100 children will be born with an additional 47th chromosome.

IMPORTANT: The fewer tests and analyzes were carried out, the less you can trust the result. Thus, the “triple test”, which determines the level of estriol, hCG and serum alpha-fetoprotein, itself produces an error in 9% of cases.

Signs of Down syndrome in a fetus can be detected by ultrasound

Test, tests for Down syndrome during pregnancy

Tests and analyzes for Down will definitely be needed for those pregnant women whose children were found to have a thickened collar space during an ultrasound scan.

At 16–18 weeks, a blood test for hormones is performed. If this test also confirms that the fetus has Down syndrome, it will be necessary to check the anatomical fluid. This procedure is carried out in a hospital and involves a puncture of the pregnant woman's abdominal cavity and collection of amniotic fluid for analysis.

IMPORTANT: After this test, the risk of miscarriage increases many times over. To do or not to do it is the business of every mother. If amniotic fluid analysis is done late in pregnancy, and it confirms the presence of genetic defects in the fetus, an abortion will not be possible—premature labor will have to be induced.

Is Down syndrome visible in a fetus on ultrasound?

If the fetus has abnormalities that indicate the likelihood of developing Down syndrome, the doctor will definitely detect them during an ultrasound. Indicators by which one can judge the possibility of the presence of the syndrome are:

• collar area enlarged
• spina bifida
• nasal bone is too small
• baby's face is flat
• little fingers are small, underdeveloped

IMPORTANT: Ultrasound results alone are not enough to obtain reliable results. Only the results of additional examinations and tests can confirm or refute the presence of Down syndrome in the fetus.

Ultrasound shows Down syndrome

Down syndrome: how to treat and is it possible to cure Down syndrome?

Down syndrome itself is not curable, as it is, in fact, a genetic error. However, children with this syndrome are born with weakened immunity and a “set” of congenital concomitant diseases. Therefore, in order to avoid the development of complications, the child must be constantly under the supervision of a number of specialists.

IMPORTANT: Despite the fact that Down syndrome cannot be cured, Sunny children need to be constantly dealt with. Regular developmental activities, proper care and treatment contribute to the socialization of Downs in ordinary society.

Down training should take place in a playful way and be supplemented by animal therapy (communication with animals). Such activities give good positive results and allow children to develop intellectually.

Risk of having a child with Down syndrome

Since Down syndrome is an error, an accident in the transmission of heredity, the risk of being born with Down exists for every healthy person. However, the risk decreases in families where there is already one down child.

Recent research by Indian scientists has led to unexpected results. It turns out that not only the age of the mother and father influence the likelihood of having a Sunny baby, but also the age of the maternal grandmother. The older she was when she gave birth to her daughter, the higher the risk that her grandchildren would be born Down.

Also, the likelihood of being born with a Down is high in cases of close family relationships.

Other factors do not in any way affect the possibility of a genetic malfunction in the fetus.

When is the risk of Down syndrome high according to the first screening?

The first screening (no earlier than 10, but no later than 14 weeks) makes it possible to suspect the presence of a genetic pathology in the fetus at an early stage. An ultrasound is performed and blood is taken to determine the amount of hormones. If both of these studies are positive, the pregnant woman is sent for a consultation with a geneticist, who in most cases prescribes two additional tests: chorionic biopsy and amniocentesis.

These tests make it possible to determine the set of chromosomes in the fetus, but they can provoke a miscarriage.

IMPORTANT: Testing for Down in the early stages has reduced the number of newborns with this genetic anomaly to 1:1000.

Blood test to determine Down syndrome

Is Down syndrome inherited?

The risk of being born with Down syndrome in a family where there are blood relatives with this syndrome depends primarily on its form. So trisomy is not transmitted, while translocation can be inherited.

IMPORTANT: If a mother has Down syndrome, then her child has a 50% risk of being born with a similar genetic disorder.

Down syndrome can be inherited

Can people with Down syndrome have children?

Men downs in most cases they cannot have children. The exception is cases of mosaic Down syndrome in males - their reproductive capabilities are preserved.

Women downs can give birth to a child, but most often they experience spontaneous abortions in the early stages.

How many years do people with Down syndrome live?

The average lifespan of people with Down syndrome is 50 years. But if in developed countries with a normal attitude towards people with disabilities and their full socialization this figure is much higher, then in Russia, Ukraine and other countries where this problem is not given due attention, it does not exceed 35.

Abroad, Down children go to regular kindergartens and schools, attend clubs and sports clubs, and receive higher education. As adults, they easily find work that does not require intense mental work.

They act in films and perform on stage, play sports and paint pictures, start families and raise children. In a word, they feel like full-fledged members of society. All this helps to prolong the life of these special people.

What makes Downs similar to each other are some common traits for this genetic disorder: eye shape, nose size, roundness of the face, body structure, as well as a cheerful, friendly disposition.

However, despite the external similarity, each of them is an individual. The character and developmental characteristics of each of these people are individual.

Prevention of Down syndrome

The only effective preventive method for Down syndrome in a child is conception and birth of a baby at a young age. Young parents are the least likely to have a child with genetic disorders.

If the mother and father of the child are over 35 - 40 years old, the woman should visit a geneticist, undergo the necessary examinations and pass all recommended tests.

IMPORTANT: If the fetus is confirmed to have Down syndrome, the woman will be offered an abortion.

Prevention of Down syndrome - conception and birth of a child at a young age

Famous people with Down syndrome

Among people with Down syndrome there are many famous outstanding musicians, actors, artists and athletes. Their records and achievements surprise, delight and inspire hope in desperate relatives of people with genetic disorders.

The whole world knows:

• Pablo Pineda– actor, the first person in the world with Down syndrome who was able to graduate from a higher education institution
• Stephanie Gins– actress who starred in the film “Duo”, which subsequently received many American film awards
• Michael Johnson- artist
• Sergey Makarov- Russian actor, plays at the Theater of the Innocent
• Ronald Jenkins– a brilliant composer, has been playing the synthesizer since he was 6 years old
• Max Lewis– English actor
• Karen Gaffney- athlete who set a world record in swimming
• Paula Sazh– lawyer, athlete, actress
• Maria Langovaya– Olympic swimming champion who won gold at the Special Olympics
• Jamie Brewer– actress who starred in “American Horror Story”

Marie Longovaya - swimmer with Down syndrome

Children with Down syndrome among famous people

As mentioned above, Down syndrome is nothing more than a genetic error. And if it could have been avoided or prevented, then who, no matter how famous and rich with their capabilities and connections, would have done it.

However, famous families of public people also give birth to downa children:

08/30/1995 Boris Yeltsin grandson Gleb was born with Down syndrome. Now the boy plays chess well, draws and plays sports.

• 1.04. 2012 actress Evelina Bledans gave birth to a son, Semyon. Now the boy is developing, just like his absolutely healthy peers. The parents learned that the child would be born with disabilities at the 14th week of pregnancy, but there was no question of killing the child. Parents are happy and enjoy raising their sunny boy
• Son's Spanish national team coach football Down syndrome. Alvaro del Bosque has been the team's mascot for 25 years. The players loved him for his friendliness and openness. Every time the guy comes to training with his father and supports his friends
• In 1997 Irina Khakamada gave birth to a special daughter, Maria, who, in addition to Down syndrome, suffered from leukemia. Now the girl is learning to draw, dances and sings well

Happy family of Evelina Bledens

Video: Evelina Bledans and her child with Down syndrome

Down syndrome symbol

The official symbol of people with Down syndrome is a blue and yellow ribbon. Those who support Downs or suffer from this syndrome themselves wear a ribbon or symbol badge on their chest.

Down syndrome symbol

March 21 is International Down Syndrome Day

Every year since 2005, on the 21st of the third month, the whole world celebrates International Down Syndrome Day. This date was not chosen by chance - it symbolizes the three twenty-first chromosomes that distinguish Downs from ordinary people.

In Russia, this day was celebrated for the first time only in 2011.

March 21 is Day of People with Down Syndrome

IMPORTANT: Down Day is celebrated with the goal of informing as many people as possible about the features of this gene pathology.

If life has decreed that a child is destined to be born down, parents should not despair, because these children are a real gift. Abroad, refusals of newborns with Down syndrome do not exceed 1% (in Russia - 95% of refusals), and the waiting list for the adoption of sunny children must be filled several years in advance.

It is enough just to change your attitude towards this genetic feature, stretch out your hands towards your own happiness and let the sunshine into your life.

Video: Close-up. Children with Down syndrome

Down's is the most commonly diagnosed chromosomal disorder. The disease was first described in 1866 by the English physician Down, who called this syndrome a special form of mental disorder. This disease caused a lot of controversy, and cases of children being born who were diagnosed with Down's disease were becoming more and more common. Experts were unable to determine the cause of the disease. In 1959, the French pediatrician Jerome Lejeune managed to establish that the disease develops due to trisomy of the twenty-first chromosome.

Why does the disease occur?

Each human cell contains a certain number of chromosomes, which are carriers of encoded genetic information. The cells of a healthy person have 23 pairs of different chromosomes, which carry genes necessary for the proper development of the body. In each pair of chromosomes, one is inherited through the sperm from the father, the second through the egg from the mother.

Why does Down's disease occur? The causes of this pathology are the inheritance of an additional chromosome set from one of the parents. Most often, these are two copies of the twenty-first chromosome from the mother and one twenty-first from the father. As a result, there are three twenty-first chromosomes, and their total number is forty-seven. This type of inheritance is called trisomy on the twenty-first chromosome.

Many women blame themselves when they find out that their child has Down syndrome. The reasons should not be looked for in yourself; chromosomes can develop incorrectly regardless of what race the parents are, what climate they live in, what their income is and level of education. There is only one reliable factor that can increase the risk of having a child with this pathology - the age of the mother. The older the woman giving birth, the higher the likelihood of giving birth to a child with Down syndrome. That is why it is necessary to carry out various tests for pregnant women over 35, which makes it possible to identify fetal disease. Many people believe that this pathology is hereditary. Down syndrome is not passed on from one generation to another.

Genetic variations of the disease

The cause of most cases of Down syndrome is trisomy 21. A child with this defect has three chromosomes in the twenty-first pair instead of two, and this is observed in all cells. Such a disorder is caused by abnormalities in cell division during the development of an egg or sperm.

But there is another form of the disease. This is mosaic Down's disease. The reasons for this rare form are defects in cell division after fertilization, and only some of them have an additional chromosome in the twenty-first pair.

When a part of a chromosome in the twenty-first pair is displaced towards another chromosome, another type of disease also occurs, which is called translocation. This shift can occur both before and during conception. Translocation is very rare.

Signs of the disease in newborns

It will not be difficult for an experienced obstetrician to recognize Down syndrome in a newborn. Signs of pathology are visible immediately after birth. From the first days, the disease can be recognized by characteristic signs: a flattened face, a skin fold on the neck, an oblique shape of the eyes, deformed ears, brachycephaly, a flattened back of the head, decreased muscle tone, excessively mobile joints, shortened limbs, the structure of the palms, lack of height and weight.

Less common signs

Such symptoms are typical for 70-90% of children who have Down syndrome. Less common signs are observed in about half of children. This is a constantly slightly open small mouth and a large tongue protruding, a narrow, arched palate, a small chin, a crooked little finger, grooves on the tongue that appear with age, a flat bridge of the nose, a short neck and nose, a horizontal fold on the palms. Such signs are enough to suspect this disease - Down syndrome - in a baby.

In addition to them, there are other appearance features that can be detected upon detailed examination. Such signs include the presence of strabismus, pigment spots along the edge of the iris, clouding of the lens, abnormal structure of the chest, defects of the digestive and genitourinary systems, an open or extra fontanelle.

In addition, children with Down syndrome are very similar to each other and do not look like their parents.

Diagnostics

Many of the signs described above may indicate a disease, or may simply be a physiological feature of the child. Therefore, based on this alone, a diagnosis cannot be made. To confirm or refute Down syndrome in a baby, you need to conduct blood tests for karyotype.

Prenatal diagnosis

To determine the presence of Down syndrome in the fetus, an ultrasound is performed in the first trimester of pregnancy. This helps to identify specific signs of Down syndrome: improperly formed skeletal bones, enlarged nuchal translucency, heart defects, enlarged renal pelvis, etc. It will not be difficult for an experienced specialist to detect the missing nasal bone, cervical folds, which indicate the accumulation of subcutaneous fluid. In addition, it is necessary to conduct a biochemical blood test of the expectant mother at 10-13 and 16-18 weeks. Down syndrome can be definitively diagnosed at the end of the fifth month of pregnancy.

Features of development

Developmental disorders of “downyat” children can be either pronounced or insignificant. Often such babies have a heart defect, sometimes this requires surgical intervention. A decrease in muscle tone causes the child to begin to walk later, and therefore to learn about the world around him. Because of this, problems arise with the development of speech and writing. In addition, such children often suffer from colds, and they often have hearing and vision impairments, which affects the overall development of the baby.

Intellectual development

It was once believed that children with Down syndrome had severe mental retardation and were unable to learn. But recently, there have been frequent cases when a person with such a diagnosis begins to live independently, gets a job, and actively participates in various types of social activities.

The reason is that the very attitude of society towards this disease has changed. Children diagnosed with Down's disease are increasingly left with families and cared for. In addition, medical care has become better; there are many special centers that work with such children. Of course, it is impossible to predict how a baby with such a deviation will develop, but this also applies to healthy children. Although such children have developmental delays, this does not mean that they are not developing. And at what pace this will happen depends on the conditions created for the baby.

Treatment and prognosis

With a disease such as Down's disease, people live approximately 40-50 years. And although the disease is incurable, concomitant diseases, such as heart disease, can be treated well, which, in turn, helps to prolong the patient’s life.

Since children with this pathology have deviations in the development of the nervous system, the expectant mother needs to take folic acid supplements, which can prevent the occurrence of more serious disorders.

When treating children with Down syndrome, social support and rehabilitation courses are of no small importance. The main goal in raising and educating such children is family and social adaptation.

Classes in groups and being in children's groups are very effective, which help improve the child's social adaptability and preparation. Such children study in specialized educational institutions, but there are cases of attending regular schools, this helps improve the child’s social preparation.

Classes with a psychologist and speech therapist are useful. When care for a sick baby is organized correctly, a child with such a disease is able to master the same skills as a healthy one, but a little later.

In order for rehabilitation measures to be more effective, it is recommended to take nootropic drugs: Aminolon, Cerebrolysin, as well as B vitamins.

Often, parents of a child diagnosed with Down syndrome do not know how to inform family and friends about this diagnosis. In this situation, it is necessary to talk frankly with loved ones in order to avoid tension in the relationship.

Parents of a sick child must remember that he is an individual with his own hopes, dreams, rights and strengths. The needs of such a baby are no different from the needs of any other child. You shouldn’t focus on this, forgetting about the rest of the family.

There is no need to treat a child with such a disease as a heavy burden. Give your baby your love, and he will answer you in kind.

Do not be embarrassed by the curious glances of strangers; treat him calmly, answering questions from friends and passers-by without embarrassment.

There is no need to refuse new acquaintances if necessary, the main thing is that you and the baby feel comfortable.

Meet parents who have children with the same disease, communicate with them, discuss issues that concern your children.

It is advisable for a child with a disorder such as Down syndrome to attend a regular school, since, studying in a specialized institution, in the eyes of other people he will look different from the rest, which means it will be more difficult for him to make friends and communicate with people. For these children, friendship with other children is very important and helps them gain the necessary social skills.

With properly organized care, early support and psychological assistance, a child with such a disease will grow up quite adequately and will give his parents positive emotions and pleasure from communication.

– a chromosomal abnormality in which the karyotype contains additional copies of genetic material on chromosome 21, i.e. trisomy on chromosome 21 is observed. Phenotypic signs of Down syndrome are represented by brachycephaly, flat face and occiput, Mongoloid incision of the palpebral fissures, epicanthus, skin fold on the neck, shortening of the limbs, short fingers, transverse palmar fold, etc. Down syndrome in a child can be detected prenatally (according to ultrasound, chorionic villus biopsy, amniocentesis, cordocentesis) or after birth based on external signs and genetic research. Children with Down syndrome require correction of concomitant developmental disorders.

ICD-10

Q90

General information

Down syndrome is an autosomal syndrome in which the karyotype is represented by 47 chromosomes due to an additional copy of chromosome 21. Down syndrome is registered with a frequency of 1 case per 500-800 newborns. The sex ratio of children with Down syndrome is 1:1. Down syndrome was first described by the English pediatrician L. Down in 1866, but the chromosomal nature and essence of the pathology (trisomy 21) was revealed almost a century later. The clinical symptoms of Down syndrome are varied: from congenital malformations and mental development disorders to secondary immunodeficiency. Children with Down syndrome require additional medical care from various specialists, and therefore they constitute a special category in pediatrics.

Causes of Down syndrome

Normally, the cells of the human body contain 23 pairs of chromosomes (normal female karyotype 46,XX; male - 46,XY). In this case, one of the chromosomes of each pair is inherited from the mother, and the other from the father. The genetic mechanisms for the development of Down syndrome lie in a quantitative disruption of autosomes, when additional genetic material is added to the 21st pair of chromosomes. The presence of trisomy on chromosome 21 determines the features characteristic of Down syndrome.

The appearance of an additional chromosome can be caused by a genetic accident (non-disjunction of paired chromosomes during oogenesis or spermatogenesis), a violation of cell division after fertilization, or the inheritance of a genetic mutation from the mother or father. Taking these mechanisms into account, genetics distinguishes three types of karyotype abnormalities in Down syndrome: regular (simple) trisomy, mosaicism and unbalanced translocation.

Most cases of Down syndrome (about 94%) are associated with simple trisomy (karyotype 47,XX, 21+ or 47,XY, 21+). In this case, three copies of the 21st chromosome are present in all cells due to disruption of the separation of paired chromosomes during meiosis in the maternal or paternal germ cells.

About 1-2% of cases of Down syndrome occur in the mosaic form, which is caused by impaired mitosis in only one cell of the embryo, which is at the blastula or gastrula stage. In mosaicism, trisomy of the 21st chromosome is detected only in derivatives of this cell, and the rest of the cells have a normal chromosome set.

The translocation form of Down syndrome occurs in 4-5% of patients. In this case, the 21st chromosome or its fragment is attached (translocated) to one of the autosomes and, during meiosis, moves along with it into the newly formed cell. The most common “objects” of translocation are chromosomes 14 and 15, less often - on 13, 22, 4 and 5. Such rearrangement of chromosomes can be random or inherited from one of the parents who is a carrier of a balanced translocation and has a normal phenotype. If the carrier of the translocation is the father, then the probability of having a child with Down syndrome is 3%; if the carriage is associated with maternal genetic material, the risk increases to 10-15%.

Risk factors for having children with Down syndrome

The birth of a child with Down syndrome is not related to the lifestyle, ethnicity or region of residence of the parents. The only reliably established factor that increases the risk of having a child with Down syndrome is the age of the mother. So, if in women under 25 years of age the probability of having a sick child is 1:1400, by the age of 35 it is already 1:400, by the age of 40 it is 1:100; and by 45 - 1:35. First of all, this is due to decreased control over the process of cell division and an increased risk of chromosome nondisjunction. However, since the birth rate in young women is generally higher, statistics show that 80% of children with Down syndrome are born to mothers under the age of 35. According to some reports, the father's age over 42-45 years also increases the risk of developing Down syndrome in the child.

It is known that if one of the identical twins has Down syndrome, the other will have this pathology in 100% of cases. Meanwhile, for fraternal twins, as well as brothers and sisters, the likelihood of such a coincidence is negligible. Other risk factors include the presence of persons with Down syndrome in the family, maternal age under 18 years, carriage of the translocation by one of the spouses, consanguineous marriages, random events that disrupt the normal development of germ cells or the embryo.

Thanks to preimplantation diagnostics, conception using ART (including in vitro fertilization) significantly reduces the risk of having a child with Down syndrome in parents at risk, but does not completely exclude this possibility.

Down syndrome symptoms

Carrying a fetus with Down syndrome is associated with an increased risk of miscarriage: spontaneous abortion occurs in approximately 30% of women at 6-8 weeks. In other cases, children with Down syndrome, as a rule, are born full-term, but have moderate hypoplasia (body weight is 8-10% below average). Despite the various cytogenetic variants of the chromosomal abnormality, most children with Down syndrome have typical external signs that suggest the presence of pathology already at the first examination of the newborn by a neonatologist. Children with Down syndrome may exhibit some or all of the physical characteristics described below.

80-90% of children with Down syndrome have craniofacial dysmorphia: flattened face and bridge of the nose, brachycephaly, short wide neck, flat back of the head, deformation of the ears; newborns - a characteristic skin fold on the neck. The face is distinguished by a Mongoloid shape of the eyes, the presence of an epicanthus (a vertical fold of skin covering the inner corner of the eye), microgenia, a half-open mouth often with thick lips and a large protruding tongue (macroglossia). Muscle tone in children with Down syndrome is usually low; there is hypermobility of the joints (including atlanto-axial instability), deformation of the chest (keeled or funnel-shaped).

Characteristic physical signs of Down syndrome are meek limbs, brachydactyly (brachymesophalangy), curvature of the little finger (clinodactyly), a transverse (“monkey”) fold in the palm, a wide distance between the 1st and 2nd toes (sandal cleft), etc. When examining children with the syndrome Down's reveals white spots along the edge of the iris (Brushfield spots), gothic (arched palate), malocclusion, and grooved tongue.

With the translocation variant of Down syndrome, external signs appear more clearly than with simple trisomy. The severity of the phenotype in mosaicism is determined by the proportion of trisomic cells in the karyotype.

Children with Down syndrome more often than others in the population have congenital heart disease (patent ductus arteriosus, VSD, ASD, tetralogy of Fallot, etc.), strabismus, cataracts, glaucoma, hearing loss, epilepsy, leukemia, gastrointestinal defects (esophageal atresia, stenosis and duodenal atresia, Hirschsprung's disease), congenital hip dislocation. Typical dermatological problems of puberty are dry skin, eczema, acne, and folliculitis.

Children with Down syndrome are often ill; they suffer more severely from childhood infections and more often suffer from pneumonia, otitis media, ARVI, adenoids, and tonsillitis. Weak immunity and congenital defects are the most likely cause of death in children in the first 5 years of life.

Most patients with Down syndrome have intellectual development disorders - usually mild or moderate mental retardation. The motor development of children with Down syndrome lags behind their peers; There is a systemic underdevelopment of speech.

Patients with Down syndrome are prone to developing obesity, constipation, hypothyroidism, alopecia areata, testicular cancer, early-onset Alzheimer's disease, etc. Men with Down syndrome are typically infertile; Women's fertility is markedly reduced due to anovulatory cycles. The height of adult patients is usually 20 cm below average. Life expectancy is about 50-60 years.

Diagnosis of Down syndrome

For prenatal detection of Down syndrome in the fetus, a prenatal diagnostic system has been proposed. First trimester screening is carried out at 11-13 weeks of pregnancy and includes identifying specific ultrasound signs of anomaly and determining the level of biochemical markers (hCG, PAPP-A) in the blood of the pregnant woman. Between 15 and 22 weeks of pregnancy, second trimester screening is performed: obstetric ultrasound, maternal blood test for alpha-fetoprotein, hCG and estriol. Taking into account the woman’s age, the risk of having a child with Down syndrome is calculated (accuracy - 56-70%; false positive results - 5%).

Pregnant women at risk of having a child with Down syndrome are offered prenatal invasive diagnostics: chorionic villus biopsy, amniocentesis or cordocentesis with fetal karyotyping and consultation with a medical geneticist. Upon receipt of information that the child has Down syndrome, the decision on whether to prolong or terminate the pregnancy remains with the parents.

Newborns with Down syndrome in the first days of life need an echocardiogram, a cardiologist, a speech therapist and an oligophrenopedagogist.

Children with Down syndrome are usually educated in a special correctional school, but within the framework of integrated education, such children can also attend a regular public school. In all cases, children with Down syndrome are classified as children with special educational needs, and therefore require additional help from teachers and social educators, the use of special educational programs, and the creation of a favorable and safe environment. Psychological and pedagogical support for families raising “sunny children” plays an important role.

Forecast and prevention of Down syndrome

The learning and socialization capabilities of persons with Down syndrome are different; they largely depend on the intellectual abilities of children and on the efforts made by parents and teachers. In most cases, children with Down syndrome manage to acquire the minimum household and communication skills necessary in everyday life. At the same time, there are known cases of success of such patients in the field of fine arts, acting, sports, as well as higher education. Adults with Down syndrome can lead an independent life, master simple professions, and start families.

Prevention of Down syndrome can only be discussed from the perspective of reducing possible risks, since the likelihood of having a sick child exists in any couple. Obstetricians and gynecologists advise women not to delay pregnancy until later in life. Genetic counseling of families and a prenatal screening system are designed to help predict the birth of a child with Down syndrome.

Belongs to a group of genetic diseases caused by mutations in sections of DNA.

The presence of Down syndrome is characterized by an anomaly of the twenty-first pair of chromosomes (the so-called trisomy), varying degrees of dementia, distinctive external signs (these include a flattened face, slanted eyes, protruding ears, an enlarged tongue, one transverse palmar fold, short stature, etc.).

Causes of Down syndrome.

Trisomy 21 chromosome tandem is the presence of three copies of chromosomes instead of two. In total, the karyotype of an organism with Down syndrome contains 47 chromosomes instead of 46, i.e. 22 pairs and 1 triple. Thus, due to a quantitative failure of autosomes, the 21st pair includes an additional molecular structure.

The normal genetic process involves 46 maternal and the same number of paternal hereditary structures - chromosomes. The complete chromosome set (karyotype) of a woman is 23 pairs XX, for men - 23 pairs XY. One of the structures of each pair is inherited by the descendant from the father, the other from the mother. The third chromosome is added to the 21st pair due to a number of independent reasons:

Paired chromosomes did not separate during the development of the egg or sperm;

Normal cell division is disrupted after fertilization;

A genetic mutation is inherited from a parent of one sex or another.

Taking these reasons into account, genetics has identified three types of karyotypic abnormalities in Down syndrome. They include the following options:

Simple (aka regular) trisomy - 94% of cases. The chromosome set with it is described as 47,XX, 21+ (for women) or 47,XY, 21+ (for men). Pathology in the twenty-first pair covers all cells of the body. This is due to a failure in the reduction division of maternal/paternal cells. Normal meiosis prevents the number of chromosomes from doubling in each generation; a distorted one can produce unnecessary genetic structure. Thus, trisomy in the maternal or paternal 21st pair is passed on to the child.

Mosaic form (mosaicism) – 1-2% of cases of the disease, in which a tripled number of chromosomes is characteristic of only some cells of the body. Mosaicism occurs due to a failure in the process of mitosis of a single germ cell. In this case, the developing organism is at the final stage of egg crushing (blastulation) or forms sources for future organs and tissues (gastrulation). In the future, trisomy will be present only in derivatives of this cell - the so-called. derivatives. Other components of the body have a normal karyotype.

An unbalanced translocation, or translocation form, is diagnosed in 4-5 percent of patients who have Down syndrome. In this case, a displacement of the 21st chromosome or part of it occurs to other structures, most often the 14th and 15th chromosomes, sometimes to the 4th, 5th, 13th, 22nd. Redeployment is random, but can be inherited from the parent. In this case, a mother or father with a normal phenotype acts as carriers of an unbalanced translocation. The likelihood of having babies diagnosed with Down syndrome depends on the gender of the parent. A father carrying NT can produce sick offspring with a probability of 3%, and a mother with displaced chromosomes can produce sick offspring with a probability of up to 10-15%.

Symptoms and signs of Down syndrome.

About 30% of women carrying a fetus with Down syndrome are at a critical gestational age of 6-8 weeks. experiencing spontaneous abortion. The remaining 70 percent safely carry the child to term. A newborn with Down syndrome differs from a normal baby in several ways or a combination of them:

Disturbances in the structure of the skull - flat bridge of the nose, face and back of the head, reduced head, deformed ear shells, thick and short neck with a characteristic occipital fold.

Facial dysmorphia - a Mongoloid shape of the eyes, their inner corners are hidden behind vertical skin folds (epicanthus). White Brushfield spots are found along the edge of the iris. Other facial signs of Down syndrome include an arched palate, abnormal bite, and underdevelopment of the lower jaw. The mouth is half-open, the lips and grooved tongue are enlarged.

Pathologies in the skeleton and muscles - the chest is deformed in a funnel- or keel-shape. There is increased joint mobility, with the so-called. atlantoaxial instability in the cervical spine. The fingers and limbs are shortened and thickened, the little fingers are curved, and there is a sandal-shaped gap between the big and second toes on the feet. Sometimes congenital dislocation of the hip occurs.

Newborn babies with Down syndrome are 8-10 percent behind normal peers in weight. External signs of the disease are characteristic of most children with a potential diagnosis, regardless of the variants of chromosomal pathology. The set of physical manifestations of Down syndrome depends on the variant of the syndrome. Translocation gives greater clarity of external signs than with regular trisomy. Children with the mosaic form of Down syndrome demonstrate different severity of the phenotype, which depends on the proportion of trisomic components in the chromosome set.

With Down syndrome, congenital heart defects can also be detected - tetralogy of Fallot, anomaly of the septum - interatrial (ASD) and interventricular (VSD). Patent ductus arteriosus (PDA) and other congenital heart defects are common. Eye pathologies (strabismus, glaucoma or cataracts), and hearing problems such as hearing loss are common. In the early stages of life, children with Down syndrome develop defects of the digestive system - stenosis/atresia in the duodenum, esophageal atresia, as well as constipation and Hirschsprung's disease. Some psychoneurological problems are typical: mild or moderate dementia, systemic speech underdevelopment, impaired motor development, epilepsy, early Alzheimer's disease. Endocrine pathologies are observed: hypothyroidism, obesity, alopecia areata (rounded patches of baldness), infertility in men, ovulation disorders in women. People with Down syndrome are often diagnosed with leukemia and testicular cancer. In adolescence, dermatological problems are common - dry skin, eczema, folliculitis, acne.

The life expectancy of those diagnosed with Down syndrome reaches 50-60 years. In the first five years, many children with Down syndrome die due to a weakened immune system and birth defects. Such children get sick more often than ordinary children and suffer from illnesses more difficult. They are more prone to the progression of pneumonia, adenoiditis, easily catch ARVI, and often suffer from otitis media and tonsillitis. Even in adulthood, those with Down syndrome are about 0.2 m below average in height.

Diagnosis of Down syndrome.

Early detection of the presence of Down syndrome is facilitated by the system of prenatal screening of the fetus in the mother's womb. In the first trimester, diagnosis is performed at a gestational age of 11-13 weeks. The goal is to identify the specifics of abnormalities on ultrasound, as well as determine the level of biochemical markers in the mother’s blood. Such markers include hCG, PAPP-A. Screening in the second trimester is done between the 15th and 22nd weeks of pregnancy. The list of examinations to detect Down syndrome includes obstetric ultrasound, maternal blood test for hCG, AFP, and the hormone estriol. Calculations of the risk of having a baby with Down syndrome are carried out taking into account the age of the pregnant woman. Accuracy ranges from 56 to 70 percent, and the pseudo-positive rate is 5 percent.

Expectant mothers who are at risk for fetal Down syndrome are recommended to undergo invasive prenatal diagnostics. This type of internal examination includes manipulations such as chorionic villus biopsy, amnio- or cordocentesis with determination of the chromosome set of the fetus. Additionally, a consultation with a medical geneticist is prescribed. If research data confirm a high risk of Down syndrome, then parents should decide whether to continue or terminate the pregnancy.

In the first days of extrauterine life, newborns with Down syndrome should undergo an echocardiogram plus an ultrasound examination of the abdominal cavity. All this is carried out in order to detect congenital defects in the development of internal organs. Children are also examined by pediatric specialists: a cardiologist, a surgeon, an ophthalmologist and an orthopedic traumatologist.

Treatment of Down syndrome.

Even under modern conditions, chromosomal abnormalities such as Down syndrome cannot be cured. Experimental therapies that may be offered to a child do not have proven clinical effectiveness. A patient with Down syndrome needs systematic medical monitoring and timely pedagogical assistance. This contributes to the successful development of children, their adaptation to social life, as well as their development of work and self-service skills.

Throughout their lives, people with Down syndrome should be under medical supervision. These include a pediatrician, therapist, cardiologist, neurologist, ENT, ophthalmologist and other doctors. The need for such control is associated with the risk of developing or the presence of associated diseases. If a patient with Down syndrome has severe congenital heart disease or gastrointestinal defects, early surgical intervention is recommended. For severe hearing loss, a hearing aid is selected. Pathologies of the visual organs require wearing glasses or ophthalmological surgery to eliminate glaucoma, cataracts, and strabismus. Hormone replacement therapy is carried out for hypothyroidism - a lack of thyroid hormones.

Motor skills and abilities in children with Down syndrome are stimulated with the help of physiotherapy and physical therapy. A speech therapist and an oligophrenopedagogist help children develop speech and communication.

Patients with Down syndrome receive general education in special correctional schools, but some are able to study in a regular school. Such cases are possible under integrated education programs. Children with Down syndrome have special learning needs. It is not easy for them, so they need qualified assistance from class teachers, subject teachers and social workers. In addition to special educational programs, children with Down syndrome need a supportive and safe environment, and their families need psychological and pedagogical support.