A Edwards syndromeIt's a genetic change characterized by trisomy 18, which means that the individual has an extra chromosome 18. It occurs when there is a failure in the chromosome disjunction mechanism during cell division, which causes There are three copies of this chromosome, not just two, which is what happens in cases where there is no flaw in this chromosome. mechanism. As it is a condition that triggers several malformations and compromises the proper functioning of organs, the mortality rate is quite high.
Read too:Turner syndrome — genetic alteration in which there is total or partial loss of the second sex chromosome
Edwards syndrome summary
Edwards syndrome is a genetic disorder characterized by the presence of an extra copy of chromosome 18.
It is caused by a failure in the cell division mechanism that causes the chromosome 18 is presented in triplicate.
It is a disorder that affects several systems of the human body, generating neurological, systemic and cognitive problems.
Its diagnosis can be made before birth using non-invasive methods.
Available treatments can be intensive, involving surgery, or focused on patient comfort through physiotherapeutic strategies.
Life expectancy in Edwards syndrome is low, as the condition affects the functioning of several body systems.
In Brazil and around the world, it is the syndrome involving trisomy that occurs most frequently, after Down syndrome.
It was first described by John Edwards and his collaborators in 1960.
What is Edwards syndrome?
Edwards syndrome is a genetic alteration characterized by trisomy 18, which means that the individual has an extra autosomal chromosome 18. After Down syndrome (trisomy 21), Edwards syndrome is the most common trisomy in humans, affecting approximately 1 in every 8,000 live births.
Causes of Edwards syndrome
→ Trisomy 18
Edwards syndrome occurs when there is a failure in the cell division mechanism in which chromosomes do not disjunct during gametogenesis. This failure in the segregation and disjunction of chromosomes causes three copies of chromosome 18, not just two, as happens when there are no failures in the mechanism.
→ Advanced age of the pregnant woman
Edwards syndrome, like other syndromes caused by trisomies, has higher incidence in older pregnant womenTherefore, in-depth medical investigation to detect Edwards syndrome is essential in pregnancies that fall under this condition.
Edwards syndrome symptoms
Edwards syndrome is a disorder that affects various systems of the human body, causing several anomalies, such as:
pre- and postnatal growth retardation;
short neck;
microcephaly;
eye defects;
cleft lip;
small oral opening;
low, malformed ears;
feet turned outward with prominent heel;
overlapping of fingers;
congenital heart defects;
anomalies in the reproductive system.
Diagnosis of Edwards syndrome
The diagnosis of Edwards syndrome is based on the analysis and verification of the presence of anomalies characteristic of this condition.
In a prenatal diagnosis, investigations are carried out using non-invasive methods, such as ultrasound and analysis of maternal serum markers, that is, substances present in maternal blood during pregnancy that may indicate complications in the development of the fetus.
Furthermore, to confirm the diagnosis of Edwards syndrome in the prenatal stage, a amniocentesis, which consists of removing part of the amniotic fluid that surrounds the fetus for analysis of the fetal karyotype. Based on the evaluation of the fetal karyotype, it is possible to determine whether trisomy 18 exists.
See too: Patau syndrome — genetic alteration characterized by trisomy 13
Edwards syndrome treatment
Edwards syndrome It does not present a definitive cure and its treatment consists of adopting strategies to improve the patient's conditions. The available treatments are divided into two aspects, one intensive — which involves surgery and the use of mechanical ventilation and more aggressive interventions — and the other based on the patient comfort — in which there are no aggressive interventions and which consists of physiotherapeutic strategies aimed at improving the psychomotor and respiratory conditions of the patient patient.
Edwards syndrome life expectancy
Life expectancy of individuals with Edwards syndrome is quite low. Around 95% of pregnancies in which there is trisomy 18 progress to spontaneous abortions and, in cases where there is Once the baby is born, the survival rate is very low, with between 5-10% of cases surviving the first year.
The high mortality rate is related to a combination of factors that affect individuals with Edwards syndrome, such as pneumonia, predisposition to infections, and congenital heart defects.
Important:Despite the low life expectancy and high mortality rate, there are records of adolescents aged 15 or over who have Edwards syndrome.
Edwards syndrome cases in Brazil
Not only in Brazil but also in the world, Edwards syndrome is the second syndrome involving chromosomal trisomy that most affects people, after Down syndrome. There are several cases of occurrence, since, worldwide, this syndrome affects 1 in every 8000 babies born alive, but it is also little known by society because it is not widespread.
In Brazil, some States are mobilizing as a way to increase visibility of Edwards syndrome, expanding spaces for discussions about this condition and promoting the dissemination of information to the population. In 2022, for example, a bill was being voted on by the Legislative Assembly of Paraná that established May 6th as Edwards Syndrome Awareness Day in the state.
History of Edwards syndrome
Edwards syndrome was first described in 1960 by Professor John Edwards and his co-workers, through the analysis of a case of a nine-week-old baby who had delayed growth and development and was born with several anomalies, including: prominent occiput, dysplastic ears, micrognathia, webbed neck, short sternum, congenital heart disease, flexed hands with overlapping fingers, and other malformations on the feet.
In the same year, other researchers described a very similar case in North America, which made it possible to describe the pattern of Edwards syndrome.
Sources
ALEP. Assembly approves Edwards Syndrome awareness day. Legislative Assembly of the State of Paraná, 19 July. 2022. Available in: https://www.assembleia.pr.leg.br/comunicacao/noticias/assembleia-aprova-dia-de-conscientizacao-da-sindrome-de-edwards.
MOURA, C.; SILVA, F.; FERRARESI, K.; ORIENTE, T. Edwards syndrome. 2003. Foundation for Teaching and Research in Health Sciences. Brasilia. Available in: http://www.luzimarteixeira.com.br/wp-content/uploads/2011/04/tapoiosindrome-de-edwards-2.pdf.
SOUSA, L.; VARGAS, T. Case report: Edwards Syndrome, physical therapy treatment in a 3-year-old child. Completion of course work. University Center of Planalto Central Apparecido dos Santos. Brasilia DF. 2020. Available in: https://dspace.uniceplac.edu.br/bitstream/123456789/1106/1/La%c3%ads%20Chaves%20de%20Sousa_0005245_Tayn%c3%a1%20Ribeiro%20Vargas_0005081.pdf.
WINK, D. V.; PEACE, F. S.; MACHADO, R. B.; WITTMANN, R. Edwards syndrome. Completion of course work. Federal Faculty of Medical Sciences Foundation. Porto Alegre – RS. 2001. Available in: http://www.luzimarteixeira.com.br/wp-content/uploads/2011/04/sindrome-de-edwards-uma-revisao.pdf.
Source: Brazil School - https://brasilescola.uol.com.br/biologia/sindrome-de-edwards.htm