Edwards syndrome is a genetic disease that occurs due to the appearance of an extra chromosome in the 18th pair. This causes a number of disorders, manifested by serious pathological abnormalities.
Edwards syndrome got its name in honor of its discoverer - Dr. John Edwards. In 1960, he first noted and recorded the features and patterns of symptoms of this deviation.
It is noteworthy that the disease is detected in 80% of women, and only in 20% of cases it is detected in men. Late pregnancy is a risk factor for having a baby with a similar anomaly. In exceptional cases, even future mothers who have not attained 30 years of age give birth to babies with this syndrome.
In 12% of cases, children live to the age when it becomes possible to assess their mental and physical development. If the syndrome appears in a newborn baby, then even if it survives, it will experience severe defects. Sooner or later they will still be the cause of death.
What it is?
Edwards syndrome is a genetic disease that involves partial or complete trisomy in the 18 autosome. The disease got its name in honor of the geneticist John Edwards, who was the first to record and describe its symptoms.
Edwards syndrome ranks second among all genetic pathologies after Down syndrome. The number of children born with this deviation is 1 to 5 - 7 thousand. Approximately in ¾ cases such anomalies are exposed to girls.
There are suggestions that a woman who is pregnant with a boy with a similar syndrome is at risk of miscarriage or fetal death.
Causes of development
Edwards syndrome is a genetic disorder that reveals 1 extra chromosome in the 18 autosome. In a healthy person, 46 chromosomes are 22 pairs of autosomes (non-sex genes), and one pair of sex genes that determine the sex of the unborn child.
Chromosomes consist of a large number of DNA strands, where all information about the human body is “encrypted” from the moment of conception to biological death. All codes are contained precisely in the strands of human DNA. In Edwards syndrome, a chromosomal rather than a gene disorder occurs that occurs due to a malfunction in the germ cell process. It is she who gives life to the future baby, after which the extra chromosome remains from her.
With the "classic" form of Edwards syndrome, chromosome 18 is doubled. Children of both sexes - male or female - may suffer from it. All cells in these children contain "extra" information, which plays a key role in the development of the disease. Violations that occur on this background, provoke the appearance of numerous external defects, and also cause disorders of the activity of internal organs. Based on the presence of a third, extra, chromosome, a term such as "trisomy" has arisen.
What is the fault of genes?
Just one extra chromosome in the child’s body can lead to numerous serious disorders that are dangerous not only for health, but also for life. The fact is that there is a special system for reading information of all cells, and if the defect in question is present, this data is doubled when cells are divided.
If there is a violation, at least in one gene, this manifests itself in the form of various pathologies, defects, anomalies. But if there is a whole “piece” or a whole extra chromosome, then such deviations will be multiple and heavy.
Chromosome 18 carries 2.5% of all genetic information, therefore, the disorders in Edwards syndrome are very significant and significant. Due to the presence of extra genes on the defective chromosome, additional proteins are synthesized, which causes disruptions in the formation and functioning of a number of internal organs and systems of the child’s body.
In Edwards syndrome, abnormalities in the urogenital system, skeleton, certain parts of the nervous system, heart and blood vessels are noted. With the development of the fetus, they are initially incorrectly formed, and after birth, and function with serious defects.
Thus, the only reason for the development of Edwards syndrome is the appearance of one extra chromosome in the maternal or paternal germ cell. The formation of germ cells is not the usual process of division, followed by doubling of 23 chromosomal pairs of up to 46 pieces, and only 23 pieces are made.
If during the division of 18 chromosomal pair is divided incorrectly, the sex cell receives 2 chromosomes at once. Ultimately, it will contain not 23, but 24. If it gives rise to a new life, this will lead to the development of Edwards syndrome in the unborn child.
Symptoms of Edwards Syndrome
The symptomatology of Edwards syndrome is diverse, and varies depending on the form of trisomy and the conditions of development of the embryo. External symptoms of the disease are as follows:
- body weight of the newborn - not more than 2.1 - 2.2 kg;
- the skull extended to a nape;
- shortening of the neck with the formation of skin folds;
- formation of cleft lip and cleft palate.
In addition, a child with Edwards syndrome can be identified by the following symptoms:
- narrow forehead;
- low ears and their irregular shape (absence of trestle, horizontal elongation, narrow auditory canals);
- wide nape;
- not fully developed lower jaw;
- small mouth;
- high sky;
- narrow palpebral fissures;
- constricted nose;
- deep nasal septum.
In Edwards syndrome, significant changes occur in the work of the musculoskeletal system. Thus, the disease may be accompanied by such signs:
- violation of the joints, so that they can not bend and unbend normally;
- foot dysplasia;
- mobility of the hip joints;
- expansion, shortening of the chest;
- splicing the toes or the formation of goose membranes between them;
- increase in the number of finger arches on the hands and lack of flexion folds.
Children with such a disability are most often subject to serious violations of the internal organs, namely:
- heart diseases such as unclosed arterial duct, defect in the formation and operation of the septum between the ventricles, etc .;
- endocrine diseases that adversely affect the growth of the body and the formation of subcutaneous tissue;
- muscle hypotonia;
- weakness of the sucking reflex;
- underdevelopment of the ovaries in girls;
- vision disorders;
- atresia of individual sections of the gastrointestinal tract;
- kidney deformity;
- doubling of the ureters.
Similar symptoms of Edwards syndrome occur in 75–90% of patients, and mental retardation (even imbecile) is present in all children with this diagnosis.
Edwards syndrome is an indication for termination of pregnancy, so its presence should be identified as soon as possible. This can be done with the help of prenatal screening - a complex of laboratory studies of maternal serum for hormones, including those produced by the fetal membrane:
- beta hCG;
- PAPP test;
- AFP (alpha-fetoprotein);
- free estriol.
It is also possible to suspect the presence of a child of this pathology during ultrasound and Doppler examination of uteroplacental blood flow. Of course, the results of such studies may be indirect, and not be the final "verdict." This applies to both instrumental and laboratory diagnostic methods.
Risk assessment of having a child with such deviations is carried out taking into account:
- gestational age;
- age of the future mother;
- biochemical and ultrasound screening data;
- body mass of a pregnant woman.
Pregnant women in the high-risk group, doctors offer to undergo prenatal diagnosis, consisting in a biopsy of chorion, amniocentesis, cordocentesis. After this, karyotyping of the fetus is performed.
If Edwards syndrome has been identified in a child after birth, it is necessary to immediately conduct a comprehensive examination to identify severe malformations. To do this, carried out inspection by a number of specialists:
- a cardiologist;
- a neurologist;
- a surgeon;
In the first hours after the birth of a child with a presumptive diagnosis of "Edwards syndrome," it is important to have an echocardiography, an ultrasound of the abdominal organs and kidneys.
Edwards Syndrome Treatment
Currently there is no cure for Edwards syndrome. Children with such a diagnosis suffer from mental and physical underdevelopment, and the issue of therapy literally leads the doctors to a dead end.
Some problems and defects help to eliminate surgical intervention, but invasive treatment is unjustified in children who barely reach days or months. For this reason, experts are inclined to palliative therapeutic tactics. It implies maintaining - above all, psychological - children born with similar abnormalities. 5 - 10% of babies with Edwards syndrome live to the age of one.
Violations of the nervous system and muscular system lead to a disorder of motor activity. Increases the risk of scoliosis, strabismus, muscle atrophy. Surgical treatment for this disease may be limited due to the risk of cardiovascular complications.
These children suffer from frequent constipation, which is a consequence of hypertonicity of the abdominal wall and intestinal atony. As a result, infants experience discomfort and also have problems with eating. To reduce the severity of symptoms, it is necessary to use special milk formulas, laxative preparations and products from the category of so-called “defoamers”. It is categorically unacceptable to resort to enema, because it can disrupt the body's electrolyte balance.
For the correction of the physical and mental development of children with this syndrome, special programs are being developed.
A negative effect on the prognosis for a child is the formation of a Wilms tumor, which is a type of kidney cancer. In this regard, it is recommended that regular ultrasound of the abdominal organs.
Sick children are often exposed to infectious diseases and other pathological conditions like:
- infectious lesions of the urogenital system;
- otitis media;
- sleep apnea;
- pulmonary hypertension;
- congenital heart defects;
- arterial hypertension.
Parents should be prepared for such a turn of events in order to respond in a timely manner to the development of a particular disease, and immediately seek medical help. In parallel with this, it is necessary to carefully monitor the general condition of the sick child, since the disease that was detected and underwent therapy on time is the key to the prolongation of the child's life.
In most cases, the prognosis for Edwards syndrome is poor. Only a few children survive to older years, but as adults they suffer from mental disorders and need constant care.
But if you regularly engage with your child regularly and correctly, they will be able to acquire important skills, develop some reflexes, and also learn how to interact with caregivers and parents.