Edwards syndrome
Edwards syndrome is the second most common genetic disorder after Down's syndrome, associated with chromosomal aberrations. In Edwards syndrome, complete or partial trisomy of the 18th chromosome is observed, as a result of which an extra copy is formed. This provokes a number of irreversible disorders of the body, which in most cases are incompatible with life. The incidence of this pathology is one case in 5-7 thousand children, while the majority of newborns with Edwards symptom are girls. The researchers suggest that male children die during the perinatal period or during childbirth.
The disease was first described in 1960 by geneticist Edwards, who identified more than 130 symptoms that characterize this pathology. Edwards syndrome is not inherited, but is the result of a mutation with a 1% chance of occurring. Factors provoking pathology - radiation exposure, consanguinity between father and mother, chronic exposure to nicotine and alcohol during conception and pregnancy, contact with chemically aggressive substances.
Edwards syndrome is a genetic disease associated with abnormal division of chromosomes, due to which an extra copy of the 18th chromosome is formed. This leads to a number of genetic disorders, which is manifested by serious pathologies of the body such as mental retardation, congenital defects of the heart, liver, central nervous system, and musculoskeletal system.
The incidence of the disease is quite rare - 1: 7000 cases, while the majority of newborns with Edwards syndrome do not live to the first year of life. Among adult patients, the majority (75%) are women, since male embryos with this pathology die even during the period of intrauterine development, which is why the pregnancy ends in miscarriage.
The main risk factor for the development of Edwards syndrome is the age of the mother, since the nondisjunction of chromosomes, which is the cause of fetal pathology, in most cases (90%) occurs in the maternal germ cell. The remaining 10% of cases of Edwards syndrome are associated with translocations and nondisjunction of the zygote's chromosomes during cleavage.
Edwards syndrome, like Down syndrome, is more common in children whose mothers become pregnant over the age of forty. (read also: Causes and symptoms of down syndrome)
To provide timely medical care to children with congenital malformations that are provoked by chromosomal abnormalities, newborns should be examined by a cardiologist, neurologist, pediatric urologist and orthopedist. Immediately after birth, the baby needs a diagnostic examination, which includes ultrasound of the pelvis and abdomen, as well as echocardiography to detect cardiac abnormalities.
Content:
- Symptoms of Edwards syndrome
- Causes of Edwards syndrome
- Diagnostics of the Edwards syndrome
- Treatment for Edwards syndrome
Symptoms of Edwards syndrome
The pathological course of pregnancy is one of the main signs of the presence of Edwards syndrome. The fetus is inactive, insufficient placenta size, polyhydramnios, only one umbilical artery. At birth, babies with Edwards syndrome are characterized by low body weight, even if the pregnancy was post-term, asphyxiation immediately after birth.
A number of congenital abnormalities in babies with Edwards syndrome lead to the fact that most of them die in the first weeks of life due to heart problems, inability to breathe and digest normally. Immediately after birth, their nutrition is carried out through a tube, since they cannot suck and swallow, there is a need for artificial ventilation.
Most of the symptoms are noticeable with the naked eye, so the disease is diagnosed almost immediately. The external manifestations of Edwards syndrome include: a shortened sternum, clubfoot, dislocated hip and abnormal rib structure, crossed fingers, the skin is covered with papillomas or hemangiomas. In addition, newborns with this pathology have a specific facial structure - a low forehead, a shortened neck with an excessive skin fold, a small mouth, a cleft lip, a convex nape and microphthalmia; the ears are set low, the auditory canals are too narrow, the auricles are deformed.
Children with Edwards syndrome have serious CNS disorders - microcephaly, cerebellar hypoplasia, hydrocephalus, meningomyelocele, and others. All these developmental defects lead to impaired intellect, mental retardation, deep idiocy.
Symptoms of Edwards syndrome are varied, the disease has manifestations on the part of almost all systems and organs - lesions of the aorta, heart septa and valves, intestinal obstruction, esophageal fistulas, umbilical and inguinal hernias. On the part of the genitourinary system, undescended testes are often found in male infants, in girls - hypertrophy of the clitoris and a bicornuate uterus, as well as general pathologies - hydronephrosis, renal failure, bladder diverticula.
Causes of Edwards syndrome
Chromosomal abnormalities that lead to the onset of Edwards syndrome occur even at the stage of formation of germ cells - ovogenesis and spermatogenesis, or appear with improper cleavage of the zygote formed by two sex cells.
The risks of Edward's syndrome are the same as for other chromosomal abnormalities, in many respects the same as those for Down's syndrome.
The likelihood of a pathology increases under the influence of some factors, among which one of the main ones is the mother's age. The incidence of Edwards syndrome is higher in women who give birth over the age of 45. Exposure to radiation leads to chromosomal abnormalities, and chronic use of alcohol, drugs, potent drugs, and smoking contributes to this. It is recommended to refrain from bad habits and avoid the influence of chemically aggressive substances in the workplace or region of residence not only during pregnancy, but also several months before conception.
Diagnostics of the Edwards syndrome
Timely diagnosis allows you to identify a chromosomal abnormality in the early stages of pregnancy and make a decision on the advisability of preserving it, taking into account all possible complications and congenital malformations of the fetus. Ultrasonography in pregnant women does not provide enough data to diagnose Edwards syndrome and other genetic diseases, but it can provide information about the course of pregnancy. Deviations from the norm, such as polyhydramnios or small fetal size, give grounds for additional research, inclusion of a woman in the risk group and increased control over the course of pregnancy in the future.
Prenatal screening is an effective diagnostic procedure to detect malformations at an early stage. Screening takes place in two stages, the first of which is carried out at the 11th week of pregnancy and consists in the study of blood biochemical parameters. The data on the threat of Edwards syndrome in the first trimester of pregnancy are not conclusive; in order to confirm their reliability, it is necessary to undergo the second stage of screening
Women who are at risk for Edwards syndrome are advised to undergo invasive testing to confirm the diagnosis, which helps develop further strategies for behavior.
Other signs indicating the development of Edwards syndrome are fetal abnormalities found on ultrasound, an abundance of amniotic fluid with a small placenta, agenesis of the umbilical artery. Doppler ultrasonography of the uteroplacental circulation, ultrasound and standard screening can help in the diagnosis of Edwards syndrome.
In addition to indicators of the state of the fetus and the pathological course of pregnancies, the grounds for enrolling the expectant mother in the high-risk group are age over 40-45 and overweight.
To determine the state of the fetus and the characteristics of the course of pregnancy at the first stage of screening, it is necessary to obtain data on the concentration of the PAPP-A protein and the beta-subunits of chorionic gonadotropin (hCG). HCG is produced by the embryo itself, and as it develops, by the placenta surrounding the fetus.
The second stage is carried out starting from the 20th week of pregnancy, including the selection of tissue samples for histological studies. Umbilical cord blood and amniotic fluid are best suited for these purposes. At this stage of perinatal screening, conclusions about the karyotype of the child can be drawn with sufficient accuracy. If the test result is negative, then there are no chromosomal abnormalities, otherwise there are grounds for a diagnosis of Edwards syndrome.
Treatment for Edwards syndrome
As with other genetic diseases caused by chromosomal abnormalities, the prognosis for children with Edwards syndrome is disappointing. Many of them die immediately at birth or within a few days, despite the medical care provided. Girls can live up to ten months, boys die within the first two or three. Only 1% of newborns live to the age of ten, while independence and social adaptation are out of the question due to serious intellectual disabilities.
Patients with mosaic form of the syndrome are more likely to survive in the first months, since not all cells of the body are damaged. The mosaic form occurs when chromosomal abnormalities occurred at the stage of zygote division, after the fusion of the male and female germ cells. Then the cell in which there was a nondisjunction of chromosomes, due to which trisomy was formed, gives rise to abnormal cells during division, which provokes all pathological phenomena. If trisomy occurs at the stage of gametogenesis with one of the germ cells, then all cells of the fetus will be abnormal.
There is no drug that could increase the chances of recovery, since it is not yet possible to intervene at the chromosomal level in all cells of the body. The only thing that modern medicine can offer is symptomatic treatment and maintenance of the child's vitality. Correction of pathological phenomena associated with Edwards syndrome can improve the patient's quality of life and prolong its duration. Surgical intervention for congenital malformations is impractical, as it entails great risks for the patient's life and has many complications.
Patients with Edwards syndrome should be monitored by a pediatrician from the first days of life, as they are very vulnerable to infectious agents. Among newborns with this pathology, conjunctivitis, infectious diseases of the genitourinary system, otitis media, sinusitis, pneumonia are often found.
Parents of a child with Edwards syndrome are often worried about whether it is possible to give birth again, what is the likelihood that the next pregnancy will also be pathological. Studies confirm that the risk of recurrence of Edwards syndrome in the same married couple is very low, even compared to an average probability of 1% of cases. The probability of having the next child with the same pathology is approximately 0.01%.
In order to timely diagnose Edwards syndrome, expectant mothers are recommended to carry out antenatal screening during pregnancy. If pathologies are found in the early stages of pregnancy, it will be possible to have an abortion for medical reasons.
Article author: Mochalov Pavel Alexandrovich | d. m. n. therapist
Education: Moscow Medical Institute. IM Sechenov, specialty - "General Medicine" in 1991, in 1993 "Occupational Diseases", in 1996 "Therapy".
