Edwards syndrome message. What is Edwards Syndrome Diagnosis?

During pregnancy, expectant mothers do prenatal screening to detect genetic abnormalities in the fetus in advance. One of the most severe diseases of this group is the syndrome described by John Edwards in 1960. In medicine, it is known as trisomy 18.

Edwards syndrome - what is it in simple words?

A healthy male and female germ cell has a standard or haploid set of chromosomes in the amount of 23 pieces. After merging, they form an individual set - a karyotype. It is like a kind of DNA passport, it contains unique genetic data about the child. A normal or diploid karyotype contains 46 chromosomes, 2 of each species, from the mother and father.

With the disease under consideration, there is an extra duplicated element in the 18th pair. This is trisomy or Edwards syndrome - a karyotype consisting of 47 chromosomes instead of 46 pieces. Sometimes the third copy of chromosome 18 is partially present or not found in all cells. Such cases are rarely diagnosed (about 5%), these nuances do not affect the course of the pathology.

Edwards syndrome - causes

Geneticists have not yet figured out why some children have the described chromosomal mutation. It is considered to be random, and no preventive measures have been developed to prevent it. Some experts associate external factors and Edwards syndrome - the reasons that presumably contribute to the development of the anomaly:

long-term use of drugs, alcohol, tobacco;
heredity;
the age of the mother or father is over 45;
genital infections;
long-term use of drugs that affect the immune, endocrine and reproductive systems;
exposure to radioactive radiation.

Edwards syndrome - genetics

According to recent studies, chromosome 18 contains 557 DNA segments. They code for over 289 types of proteins in the body. In percentage terms, this is 2.5-2.6% of the genetic material, which is why the third chromosome 18 has such a strong effect on the development of the fetus - Edwards syndrome damages the bones of the skull, the cardiovascular and genitourinary systems. The mutation affects some parts of the brain and peripheral nerve plexuses. A patient with Edwards syndrome is characterized by a karyotype shown in the figure. It clearly shows that all the sets are paired, except for the 18th set.

Frequency of Edwards syndrome

This pathology is rare, especially when compared to more well-known genetic abnormalities. Edwards syndrome disease is diagnosed in one newborn out of 7,000 healthy babies, mostly in girls. It cannot be argued that the age of the father or mother significantly affects the likelihood of trisomy 18. Edwards syndrome occurs in children only 0.7% more often if parents are over 45 years old. This chromosomal mutation is also found among babies conceived at a young age.

Edwards syndrome - signs

The disease under consideration has a specific clinical picture that makes it possible to accurately determine trisomy 18. There are two groups of signs that accompany Edwards syndrome - the symptoms are conditionally classified into internal organ dysfunction and external abnormalities. The first type of manifestation includes:

umbilical, inguinal hernia;
lack of sucking and swallowing reflex;
gastroesophageal reflux;
atresia of the anus or esophagus;
clitoral hypertrophy;
underdevelopment of the corpus callosum, cerebellum;
incorrect location of the intestine;
hypospadias;
doubling of the ureters;
atrophy or smoothing of the cerebral convolutions;
segmented or horseshoe kidney;
unformed ovaries;
curved spine;
muscle dystrophy;
low body weight (about 2 kg at birth).

Outwardly, it is also easy to identify Edwards syndrome - a photo of babies with trisomy 18 shows the presence of the following signs:

disproportionate small head;
distorted face shape;
narrow and short palpebral fissures;
deformed, low-lying auricles (elongated horizontally);
the absence of a lobe, sometimes a tragus and even an ear canal;
short and wide chest;
underdeveloped lower jaw;
small mouth, often with a triangular opening due to a pathologically shortened upper lip;
depressed extended bridge of the nose;
"foot-rocking chair";
webbing between the fingers or their fusion (flip-like limbs);
high palate, sometimes with a cleft;
short neck with prominent collar fold;
transverse furrows and scallops on the palms;
hemangiomas and papillomas on the skin;
eyelid ptosis;
strabismus;
protruding nape and low forehead.

Edwards syndrome - diagnosis

The described genetic disease is a direct indication for abortion. Children with Edwards syndrome will never be able to live fully, and their health will rapidly deteriorate. For this reason, it is important to diagnose trisomy 18 as early as possible. To determine this pathology, several informative screenings have been developed.

Analysis for Edwards syndrome

There are non-invasive and invasive methods for studying biological material. The second type of test is considered the most reliable and reliable; it helps to identify Edwards syndrome in the fetus in the early stages of development. Non-invasive is the standard prenatal screening of the mother's blood. Invasive diagnostic methods include:

Biopsy of chorionic villi. The study is conducted from 8 weeks. To carry out the analysis, a piece of the placental membrane is plucked off, because its structure almost perfectly matches the tissue of the fetus.
. During testing, a sample of amniotic fluid is taken. This procedure detects Edwards syndrome from 14 weeks of gestation.
Cordocentesis. The analysis requires a little umbilical cord blood of the fetus, so this diagnostic method is used only in the later stages, from the 20th week.

Risk of Edwards Syndrome by Biochemistry

Prenatal screening is carried out in the first trimester of pregnancy. The expectant mother must donate blood between 11 and 13 weeks of gestation for biochemical analysis. Based on the results of determining the level of chorionic gonadotropin and plasma protein A, the risk of Edwards syndrome in the fetus is calculated. If it is high, the woman is included in the appropriate group for the next stage of research (invasive).

Edwards syndrome - signs on ultrasound

This type of diagnosis is rarely used, mainly in cases where the pregnant woman has not undergone preliminary genetic screening. Edwards syndrome on ultrasound can be detected only in the later stages, when the fetus is already almost fully formed. Typical symptoms of trisomy 18:

intrauterine malformations of the cardiovascular and genitourinary systems;
anomalies of the musculoskeletal structures;
pathology of the bones of the skull and soft tissues of the head.
Indirect signs of the disease on ultrasound:
bradycardia;
delayed fetal development;
one artery in the umbilical cord (should be two);
hernia in the abdominal cavity;
visual absence of nasal bones.

Edwards syndrome - treatment

Therapy of the considered mutation is aimed at alleviating its symptoms and making life easier for the baby. It is impossible to cure Edwards syndrome and ensure the full development of the child. Standard medical measures help:

restore the passage of food with atresia of the anus or intestines;
organize feeding through a probe against the background of the absence of sucking and swallowing reflexes;
stabilize the functioning of the cardiovascular system;
normalize the outflow of urine.

Often Edwards syndrome in newborns additionally requires the use of anti-inflammatory, antibacterial, hormonal and other potent drugs. This is necessary for timely intensive therapy of all concomitant diseases that it provokes:

conjunctivitis;
pneumonia;
otitis media;
pulmonary hypertension;
sinusitis;
urinary infections;
frontitis;
high blood pressure and more.

Many people know about Down syndrome (trisomy 21). But there is less information about Edwards syndrome, although this disease is rare, but still occurs in newborns. And pregnant women need to know the risks of having a child with such a pathology.

Briefly about the disease

Edwards syndrome is a genetic pathology in which the 18th chromosome (trisomy) is disturbed, as a result of which the embryo develops with defects. Children are not born at all or are born disabled, which is not subject to treatment. With this disease, the fetus, together with forty-six chromosomes, forms the 47th, which is superfluous. Edwards syndrome is also called trisomy 18. John Edwards discovered the disease in the 60s of the last century. The syndrome is named after him.

The reasons

In the absence of a family history of this disease, with the absolute health of the parents, there is still a risk of having a child with this disease. Science knows that a human cell has 46 chromosomes. An egg and a sperm cell each have twenty-three chromosomes. When they combine, the number of chromosomes also combines. The causes of Edwards syndrome are not well understood to date.

Researchers say that due to gene mutations, one extra pair is formed in the 18th pair of chromosomes. In 2 out of 100 cases of this disease, the eighteenth chromosome is lengthened, while the 47th chromosome is not formed, but a translocation occurs.

In three out of a hundred cases of illness, doctors talk about mosaic trisomy. This means that the extra chromosome is present only in some of the cells of the fetal body, and not absolutely in all. But according to the symptoms, the three described variants of the disease converge. Only in the first case, the course can be severe and more likely to be fatal.

Frequency

In 60 cases of mutations out of 100, children with the syndrome in question die inside the mother's abdomen, because of the defects are incompatible with life. But the survival rate of children with Edwards syndrome is quite high (slightly lower than that of fetuses with). For 3-8 thousand babies, one is born with the diagnosis in question.

Doctors say that among female infants, the disease occurs three times more often than among boys. There is a high risk of giving birth to a child with these abnormalities in women in labor who are over 30 years old. During the first 12 months of life, about 90 out of 100 children with this diagnosis die. Boys live an average of 2 to 3 months, and girls about 10 months. The chances of a child with Edwards syndrome surviving to adulthood are slim. Complications of malformations become the causes of death of children:

cardiovascular failure
pneumonia
suffocation

Symptoms

The manifestations of the disease are divided into several groups. The first are those that characterize the appearance sick person:

body weight at birth is approximately 2 kg 100 grams or 2 kg 200 grams
abnormally developed lower or upper jaw
the head is small in relation to the whole body
cleft lip and/or hard palate
malocclusion and irregular shape of the child's face
rocking foot
from birth
webbing on the toes or complete fusion of the toes
ears set low
the fingers of the hand are compressed, their uneven arrangement in the cam is observed
mouth opening is smaller than it should be

The second group of symptoms of the disease concerns neuropsychic sphere, motility and organ functions sick child:

umbilical or
congenital heart defects, including patent ductus arteriosus, ventricular septal defect, etc.
smoothing or atrophy of the cerebral convolutions
underdevelopment of the cerebellum, corpus callosum
delayed neuropsychic development of the child
disruption of the bowel
Meckel's diverticulum
atresia of the esophagus or anus
violation of the swallowing and sucking reflex
doubling of the ureters
horseshoe or segmented kidney
underdevelopment of the ovaries in girls
hypertrophied clitoris in female infants
hypospadias in male infants
in sick boys
amyotrophy
scoliosis
strabismus

Diagnostics

You can most often find out about genetic pathologies while a woman is still carrying a child. This also applies to trisomies. carried out from the 11th to the 13th week. A woman takes blood tests (biochemistry), ultrasound is performed. Also, the diagnosis consists in determining the karotype of the embryo, if the woman is at risk (aggravated family history, infectious diseases in the first trimester, etc.).

In the screening of the first semester, it is determined how much human chorionic hormone and plasma protein A associated with pregnancy are in the blood. Then the age of the pregnant woman is taken into account to find out with what risk she may have a child with trisomy 18.

If a woman is classified as a risk group, a fetal biopsy is done a little later to know for sure whether the baby will be born with abnormalities or healthy. From 8 to 12 weeks, an analysis of the chorionic villi is taken. From the 14th to the 18th week, a study of the waters surrounding the fetus is carried out. After the 20th week, cordocentesis can be done. The procedure involves taking blood from the umbilical cord (in the process, ultrasound is used to control the taking of the material).

The number of chromosomes is found in the material. This is where the QP-PCR method helps. If a pregnant woman does not undergo genetic screening at late gestation, a preliminary diagnosis of a genetic mutation is made by ultrasound. In the second and third trimester, there are signs that indicate that a child is more likely to be born with trisomy:

low-lying fetal ears
microcephaly
cleft palate
malformations of the musculoskeletal system
malformations of the genitourinary system
malformations of the heart and blood vessels

Diagnosis after birth

Edwards syndrome in newborns is detected by the following signs:

low weight newborn
cleft palate or cleft lip
transverse palmar groove
undeveloped distal flexion fold on the fingers
distal location of the axial triradius and increased ridge count in the palm
arches on the fingertips

But these signs do not yet indicate that the child has Edwards syndrome. The diagnosis needs to be confirmed. For this purpose, the above-mentioned method of KF-polyplasma chain reaction is used to determine the caropine of the newborn. Ultrasound shows vascular plexus cysts in an infant.

Diagnosis by ultrasound before birth

Such indirect signs of the disease are revealed, starting from the twelfth week of gestation:

1, not 2 umbilical arteries
bones of the nose on ultrasound are not visualized
abdominal hernia
low heart rate
vascular plexus cysts

Cysts are not dangerous for the baby; they are eliminated at the 26th week of gestation. But such cysts indicate that the child has a genetic developmental anomaly. This may be the syndrome discussed in this article. Cysts are found in a third of patients with this diagnosis. If the doctor sees cysts on ultrasound, then the next step in prenatal diagnosis is a consultation with a geneticist.

Treatment of Edwards syndrome

The goal of therapy is to correct developmental malformations that are life-threatening for the child. But it is worth remembering that the child may have serious disabilities, and he is unlikely to live to 12 months of age. If pneumonia is detected, then the baby is given anti-inflammatory drugs and antibiotics. If it is found that the baby does not have a sucking and swallowing reflex, then he is fed with a probe. If a patient has atresia of the anal or intestines, it is necessary to restore the passage of food.

If the doctor sees that the course of Edwards syndrome is favorable, then an operation is needed to eliminate the umbilical hernia, inguinal hernia, heart defects, and the cleft palate. Some symptoms can be relieved by medication. For example, if an infant is constipated, he will need certain laxative medicines. With the accumulation of gases in the intestines, drugs from a number of "antifoaming agents" are prescribed.

Children who have the trisomy in question are at risk of such diseases:

urinary infections
sinusitis and frontitis
apnea
pulmonary hypertension
pneumonia
kidney cancer
otitis media

It is important to find these diseases in the baby in time and treat them correctly. The prognosis in most cases of the disease is unfavorable. As already noted, a child has an extremely low chance of surviving to puberty. If the child survives, he needs vigilant care and control, because his brain will not be sufficiently developed. Some patients can eat without the help of outsiders, and also smile and acquire minimal skills.

Edwards syndrome is a form of a rare genetic disorder where part of a person's chromosome 18 is duplicated. Most children with this pathology die at the stage of embryonic development, this happens in 60% of cases. The prevalence of Edwards syndrome averages 1:3000-1:8000 cases. The syndrome is not inherited, and the chance of this mutation is only 1%.

Edwards syndrome was named after Dr. John Edward, who in 1960 described the first cases and recorded the pattern of symptoms. Edwards syndrome affects more women than men - about 80 percent of those affected are women. Women over thirty years of age have a greater risk of having a child with the syndrome, although the same can happen to women under thirty, but much less often. About 12% of children with the syndrome survive to an age when mental development can be assessed; babies who survive have severe defects and usually do not live long. Edwards syndrome is associated with a wide range of disorders that consist of more than one hundred and thirty discrete defects associated with the brain, heart, craniofacial structure, kidneys, and stomach.

Causes of the development of Edwards syndrome.

Each cell in the human body contains twenty-three pairs of chromosomes, which he inherits from his parents. In humans, each sex cell contains the same number of chromosome sets. In women, these are eggs (called XX), and in men (called XY), these are sperm. During the division of a fertilized egg, a mutation occurs under the influence of any factors and an additional chromosome appears in the eighteenth pair, which is responsible for the occurrence of Edwards syndrome. Children with the syndrome inherit the wrong number of chromosomes; instead of having two copies, they have three copies of the chromosomes. This type of mutation is called “trisomy”, and the number of the pair in which the mutation occurred is also attached to the name, in the case of Edwards syndrome, this is the eighteenth pair.

The variant described above is a "complete trisomy", that is, the child has inherited a complete additional copy of the extra chromosome, such children with Edwards syndrome, according to statistics, 95%. "Complete trisomy" has almost all the signs of the disease and is very difficult.

There are two more variants of mutations. Two percent of children with Edwards syndrome have a translocation on pair 18, where only part of the extra chromosome is present. Three percent of children with the syndrome have "mosaic trisomy", this type of mutation is characterized by the presence of an extra chromosome in not all cells of the body.

Symptoms of Edwards syndrome.

Most children born with Edwards syndrome are underweight and severely retarded. Their head is unusually small, and the back of the head has a pronounced size. Their ears are set low and their upper and/or lower jaws have a developmental defect called micrognathia. This is a condition when the shape of the face is distorted and an incorrect bite is formed.

Children often develop "cleft palate" and "cleft lip", conditions where there is a cleft in the upper palate and lip, respectively.

Formed "cleft lip"

Children's hands are often clenched into fists and all fingers have a characteristic uneven position.

Children suffer from clubfoot, and the fingers on the lower extremities may be webbed or completely merge with each other.

Very often, patients with the syndrome have problems with the heart, lungs and diaphragm due to the pathology of the vascular link and the development of congenital malformations. Heart defects can have a different character and a different number: open ductus arteriosus, ventricular septal defect, open foramen ovale.

Mutations can cause the development of inguinal and umbilical hernias, anomalies in the development of the genitourinary system, and dysplastic syndrome. The percentage of the development of a particular defect:

Damage to the system and defect (sign) - Frequency %
Brain skull and face - 100%
microgenia - 96.8%
low location and / and deformation of the auricles - 95.6%
dolichocephaly - 89.8%
high sky - 78%
split sky - 15%
microstomy - 71%
Musculoskeletal system - 98.1%
flexor position of the hands - 91.4%
rocking foot - 76.2%
cutaneous syndactyly of the feet - 49.5%
clubfoot - 34.9%
Central nervous system - 20.4%
Cardiovascular system - 90.4%
Digestive organs - 54.9%
Genitourinary system - 33.5%

Children with Edward syndrome tend to have feeding problems. Problems arise due to a violation of the innate reflexes of swallowing and sucking. Weak development of the sucking reflex and inconsistent swallowing leads to suffocation of the child.

The child may develop gastroeosophageal reflux disease. Congenital clefts of the facial skeleton also cause feeding difficulties. They lead to the need to feed the child through a tube or gastrostomy. A specialist can show the child's parents how to properly hold their child's head and body. To prevent reflux, the baby's head should be elevated about thirty degrees or more while the baby is eating and for an hour or two after he has eaten.

Diagnosis of Edward's syndrome

The diagnosis of Edwards syndrome can be made by identifying all of the above external symptoms on physical examination. A more definitive diagnosis can be made by doing a "karyotyping" test, which involves taking samples of the baby's blood to determine the chromosomal makeup.

Due to the large number of malformations and the very low survival rate of children with Edwards syndrome, antenatal diagnostic methods have now been developed. One of the first and most affordable techniques that are carried out in all antenatal clinics is fetal ultrasound. On ultrasound in early pregnancy, malformations of the brain and limbs can be suspected, as well as the presence of an abundant amount of amniotic fluid, which should alert the doctor. Upon receipt of these results, it is necessary to send the pregnant woman for more detailed and targeted observation to the hospital.

In the hospital, they must perform all the necessary general clinical tests and conduct more specific tests, such as echography, dopplerography, and the study of serum blood markers: β-subunit of chorionic gonadotropin (βCG), α-fetoprotein (AFP), estriol (E3), 17-hydroxy progesterone . To assess the risk of giving birth to children with chromosomal pathology in all cases, a specially developed computer program PRISCA is used, taking into account the woman's age, serum markers and gestational age. It is also necessary to perform a transabdominal amniocentesis followed by cordocentesis. In the amniotic waters in the presence of Edwards syndrome, the following will be determined: AFP, 17-OP, EZ, and in the blood of the fetus, the karyotype of trisomy 18 chromosomes will be determined.

Treatment of Edwards syndrome

The scientific medical community does not currently know of a cure for the syndrome. Babies with Edwards syndrome are usually born with physical abnormalities, and doctors face a challenge in deciding which treatment to take. Surgery can correct some of the malformations associated with the syndrome, but the invasiveness of the technique does not justify the outcome in children whose lifespan ranges from a few days to months.

Treatment today is limited to palliative care (supporting the morale of those faced with a fatal disease). Five to ten percent of children with Edwards syndrome survive into their first year of life.

Problems associated with disorders of the nervous system and muscle tone affect the development of the child's motor skills, which can lead to scoliosis, muscle atrophy, and strabismus. Surgical treatment in sick children may be limited due to malformations of the cardiovascular system. Children with the syndrome often have constipation caused by poor abdominal wall tone and atonic bowel. As a result, infants experience discomfort, feeding difficulties. Special milk formulas, laxatives, and drugs from the "antifoaming" group can relieve these symptoms. Enemas in this situation are contraindicated because they can lead to electrolyte imbalance in the child.

Children with the syndrome often lag behind in development, in connection with this, it is necessary to use specially designed therapy programs to correct the delay in physical development.

Another factor in the poor prognosis is an increased risk of developing Wilms' tumor - this is one of the varieties of kidney cancer. Regular ultrasound examination of the abdominal cavity for the presence of this pathology is recommended.

Sick children are at risk of developing various infections and pathological conditions, such as: infections of the genitourinary system, otitis media, conjunctivitis of various etiologies, sinusitis, frontal sinusitis, pneumonia, sleep apnea, pulmonary hypertension, congenital heart defects and high blood pressure. It is necessary to be prepared in order to effectively treat and suspect these diseases in time.

Parents whose child has this syndrome need constant monitoring of the state of health, since a timely detected disease can prolong the life of their children.

Edward syndrome prognosis

For the most part, the prognosis for this pathology is not favorable. Most children who are born with Edwards syndrome do not live past their first year of life. The average life expectancy for half of the children born with this syndrome is less than two months. Ninety to ninety-five percent of these children die before their first birthday. Five to ten percent of children who survive their first year experience severe developmental disabilities.

Children who have lived through the first year require constant monitoring and supervision, and experience serious developmental difficulties. Their verbal communication skills are limited, although they are able to respond to their parents' comfort and have the opportunity to learn to smile, recognize and interact with caregivers and others. They can learn skills that all babies need, such as self-feeding and head-lifting, skills that are typical for healthy children their age.

Therapist Zhumagaziev E.N.

Edwards syndrome or trisomy 18 is one of the most severe congenital diseases.

This disease is provoked by a violation in the rows of chromosomes.

The syndrome causes numerous diseases of organs and systems in the human body.

Interesting fact: among sick children, girls with Edwards syndrome are 3 times more common than boys.

Edwards syndrome - what is it?

As you know, the normal set of chromosomes in the human body is 23 pairs, or 46 pieces, which a child receives from his parents at conception.

In the presence of Edwards syndrome in the 18th pair of chromosomes in a child, in simple words, a copy of it appears (hence the name of the syndrome - trisomy 18).

Sometimes it manifests itself partially, but this happens very rarely - in about 5% of cases.

Causes and provoking factors

To date, it is not fully understood why children can develop this disease.

Many scientists are of the opinion that the occurrence of this syndrome is completely accidental; other experts argue that there are still factors that can affect the occurrence of chromosome 18.

Among them are the following causes of the syndrome:

hereditary factor;
the age of one of the parents is more than 45 years;
the mother's use of alcohol, drugs, smoking cigarettes and taking drugs that can affect the immunity and endocrine system of the unborn child and the woman herself;
genital tract infections in parents during conception;
radioactive radiation to which the mother was exposed during pregnancy or shortly before it.

All these factors are indirect, due to the fact that in some children with this syndrome, the parents never even had signs similar to those previously indicated.

For this reason, each specific case of the manifestation of this syndrome in children should be considered individually by specialists.

Symptoms of the disease

The syndrome manifests itself in all children in completely different ways: some have only the main symptoms of the disease, while others have their absolute majority.

The degree of manifestation of existing symptoms is also different in patients.

So, outwardly, Edwards syndrome manifests itself as follows:

the child has a small head compared to the body;
narrow eyes (see photo above);
poorly developed lower jaw;
distortion of the features and shape of the face;
elongated ears. Often, some constituent parts of the ear (lobe, auditory canal) are also missing;
wide and short chest;
upper lip very small, small mouth;
greatly expanded bridge of the nose, sometimes "depressed" inside the skull;
feet of irregular shape;
high sky with a slit ();
low forehead, the back of the head strongly protrudes;
strabismus.

In addition to visual signs, there are also internal, much more serious in nature:

heart disease;
the presence of hernias;
lack of reflexes typical of young children;
underdevelopment of the cerebellum;
double ureters;
small body weight, about 2 kg at birth;
dementia develops with age;
muscle dystrophy;
oncology of various organs.

Types of Edwards Syndrome

Depending on the type of chromosomal defect in the 18th pair, there are three main types of Edwards syndrome.

I. Complete trisomy 18. The most severe type of manifestation of the syndrome and, unfortunately, the most common (90% of cases). This type implies that all cells of the body have a copy of the chromosome.

II. Partial trisomy 18. This type of syndrome is extremely rare. Such a trisomy consists in the fact that only a certain part of the chromosome is contained in the cells of the body. This can happen due to improper cell division.

It happens that this fragment of a chromosome is built into the structure of another chromosome. In this case, the number of manifestations of the disease will be much less in number.

III. Mosaic trisomy 18. It is also a rather rare form of Edwards syndrome, but it manifests itself in a completely different way than the previous forms of the disease.

In this case, the failure occurs later than the fusion of the male and female germ cells, in the process of division.

After this failure, a copy of the chromosome appears in the 18th pair of chromosomes, which causes the further development of Edwardson's syndrome.

Diagnostics

If the described syndrome is detected in an unborn child, it is an indication for terminating the pregnancy.

This is due to the fact that children with trisomy 18 cannot live a full life, and their health is getting weaker and weaker every day.

To detect a disease during pregnancy, a number of studies and analyzes are carried out:

Cordocentesis. For analysis, the umbilical cord blood of the fetus is taken. This method is used for a period of more than 20 weeks.
Amniocentesis. To conduct a study of amniotic fluid. The procedure is allowed starting from the 14th week.
Biopsy. The study is carried out after 8 weeks. For this, a small part of the placenta is taken, because it is almost the same as the tissue of the fetus.

Many women are aware of Down syndrome. However, during pregnancy, they learn about the existence of other chromosomal abnormalities, one of them is Edwards syndrome.

Edwards syndrome is a chromosomal abnormality characterized by abnormalities in the growth and development of infants and may even lead to miscarriage or stillbirth. Children with this diagnosis have three copies of the eighteenth chromosome, so this syndrome is often called trisomy 18.

Pediatrician, gastroenterologist

Every cell of the human body normally contains 23 pairs of chromosomes inherited from parents. When a sperm cell and an egg unite to form an embryo, their chromosomes unite. The baby receives 23 chromosomes from the father's sperm and 23 from the mother's egg, for a total of 46.

Sometimes an egg or sperm cell has the wrong number of chromosomes. As the cells of the father and mother unite, this distortion is transmitted to the child.

"Trisomy" means that the child has an extra chromosome in all or some of the cells. With trisomy 18, the baby has three chromosomes 18. This leads to the abnormal development of many organs in the baby.

Typically, trisomy 18 is caused by an extra chromosome 18 in each cell. About 5% of affected people have an extra chromosome 18 in some, but not all, cells. This is mosaic trisomy. It can be very severe or barely noticeable, depending on the number of cells that have the extra chromosome.

Rarely, there is no extra chromosome; part of the long arm of chromosome 18 joins with another chromosome during the formation of sperm and egg or at the beginning of embryonic development. In this case, the individual has 2 chromosomes 18 and additional material from chromosome 18 that is attached to another chromosome. This phenomenon is called translocation.

The extra genetic material causes developmental abnormalities just like having an entire extra chromosome. The signs and symptoms of this form of trisomy depend on the amount of chromosome material that has been transferred to the other chromosome.

About the mechanism of inheritance

Most cases of the syndrome are not inherited. It occurs due to random events during the formation of the egg and sperm. An error in division results in a reproductive cell with the wrong number of chromosomes. For example, a sperm or egg may have an extra copy of chromosome 18. When one of these atypical reproductive cells contributes to a child's genetic make-up, the child will have an extra chromosome 18 in all cells.

Mosaic trisomy 18 is also not inherited. It is caused by random events during cell division at the beginning of embryonic development. As a result, some cells contain two copies of chromosome 18, while others contain three copies of this chromosome.

Translocation trisomy may be inherited. An unaffected individual carries a rearrangement of genetic material between chromosome 18 and another chromosome. Although it does not show signs of trisomy 18, a person who has this type of translocation is at an increased risk of having children with this genetic disorder.

Epidemiology

Edwards syndrome is the second most common autosomal trisomy among living children after.

Trisomy 18 occurs, on average, in 1 in every 5,000 children. Girls are affected much more often than boys. Any woman can have a baby with trisomy 18, but the risk increases with the age of the mother.

Signs of Edwards Syndrome

Babies born with trisomy 18 may have some or all of these characteristics:

malformations of the kidneys;
structural heart defects at birth (ventricular and atrial septal defects, patent ductus arteriosus);
bowel protruding outside the body (omphalocele);
esophageal atresia (obstruction of the esophagus);
mental retardation;
developmental delay;
growth deficit;
feeding difficulties;
breathing difficulties;
arthrogryposis (joint stiffness).

Some of the physical malformations associated with Edwards syndrome include:

small head (microcephaly);
low-lying, malformed ears;
an abnormally small jaw (micrognathia);
cleft lip/cleft palate;
inverted nose;
narrow, wide-set eyes (ocular hypertelorism);
drooping of the upper eyelids (ptosis);
short sternum;
clenched hands;
underdeveloped thumbs and/or nails;
fusion of the second and third toes;
clubfoot;
boys have undescended testicles.

In the womb, the most common feature is cardiac and CNS abnormalities. The most common intracranial pathology is the presence of choroid plexus cysts, which are pockets of fluid in the brain. Sometimes there is an excess of amniotic fluid.

In newborns, chromosomal analysis may be done to determine the exact cause of birth defects.

Possible prenatal studies for trisomy 18:

Measurement of the level of alphafetoprotein. The test is carried out between 15 and 17 weeks of pregnancy. A positive test result does not mean that the child will have trisomy 18 or any chromosomal abnormality. In fact, only about 11% of those women who test positive for trisomy 18 on this test will actually have an affected fetus.
Ultrasound is another widely used screening test. As with the above study, a simple ultrasound cannot be used to diagnose trisomy 18. A more detailed study using ultrasound waves can be performed to look for characteristic signs of an anomaly, but this method cannot confirm the presence of the syndrome.
Analysis of fetal chromosome material obtained from amniocentesis or chorionic villus biopsy is needed to prove that there is an extra copy of chromosome 18. Amniocentesis is usually performed at 15 to 18 weeks of gestation and is the most commonly used test for prenatal diagnosis of trisomy 18. During this procedure A thin needle is inserted through the abdominal wall and a small sample of amniotic fluid is taken. Chorionic villus biopsy is another type of study that allows you to study the genetic material of the fetus. The test is performed 10 to 12 weeks after the last menstrual cycle and therefore has the advantage of allowing an earlier diagnosis. This procedure involves collecting a sample of chorionic villi from the placenta either by puncturing the abdominal wall or by using a catheter through the vagina.

Currently, medical science has not found a cure for Edward's syndrome. Infants with the syndrome usually have severe physical impairments, and physicians have difficulty making choices about their treatment. Surgery can help treat some of the problems associated with the syndrome. Today, treatment mainly consists of palliative care (maintaining and improving the quality of life of affected patients).

Approximately 5 - 10% of children with Edward syndrome survive beyond the first year of life due to the treatment of various chronic pathologies associated with the syndrome. Problems associated with abnormalities of the nervous system and muscle tone affect the development of motor skills in an infant, which can lead to and. The use of surgical intervention methods is limited due to the presence of heart disease.

Babies with Edward's syndrome may be constipated due to poor abdominal muscle tone. This can result in discomfort, irritability, and eating problems. Specialized milk formulas, gas medications, laxatives, stool softeners, and suppositories are potential treatments that a doctor may recommend.