What is Trisomy 18?
Trisomy 18, also known as Edwards syndrome, is a genetic disorder caused by the presence of an extra chromosome 18. This results in severe developmental and medical complications which can affect nearly every organ system in the body. It is one of the more common trisomies, second only to
Trisomy 21 (Down syndrome).
How Common is Trisomy 18?
Trisomy 18 occurs in about 1 in 5,000 live births. However, many fetuses with Trisomy 18 do not survive to term, and the condition is more common in miscarriages. The risk of having a baby with Trisomy 18 increases with maternal age.
What are the Symptoms?
Infants with Trisomy 18 often present multiple
congenital anomalies. Common symptoms include low birth weight, heart defects, kidney abnormalities,
microcephaly (small head), and
clenched fists with overlapping fingers. Other features may include a small jaw (micrognathia), low-set ears, and severe intellectual disability.
How is Trisomy 18 Diagnosed?
Diagnosis can occur prenatally or postnatally. Prenatal diagnosis typically involves
ultrasound and non-invasive prenatal testing (NIPT), which analyzes fetal DNA in the mother's blood. Confirmatory testing includes chorionic villus sampling (CVS) or amniocentesis to analyze the fetal karyotype. Postnatally, a diagnosis is confirmed through a blood test to examine the baby's chromosomes.
What are the Treatment Options?
There is no cure for Trisomy 18, and treatment focuses on managing symptoms and improving quality of life. This may include interventions for heart defects, feeding difficulties, and respiratory issues. A multidisciplinary team including
pediatric cardiologists, nephrologists, neurologists, and geneticists often provides care. Palliative care and hospice services may also be considered.
What is the Prognosis?
The prognosis for infants with Trisomy 18 is generally poor. More than 90% of affected infants do not survive past the first year of life. Those who do survive often have severe intellectual and physical disabilities. Early intervention and supportive care can improve outcomes and quality of life for some children.
How Can Parents Cope?
Receiving a diagnosis of Trisomy 18 can be overwhelming for parents. Genetic counseling can provide valuable information and support. Many parents find it helpful to connect with support groups and organizations dedicated to trisomy conditions. These resources can offer emotional support, practical advice, and a sense of community.
Is There Any Ongoing Research?
Research on Trisomy 18 is ongoing, focusing on better understanding the condition, improving diagnostic methods, and developing new treatments. Studies are also exploring the effects of early intervention and the long-term outcomes for children who survive beyond infancy.
Conclusion
Trisomy 18 is a severe genetic disorder with significant impacts on affected infants and their families. Early diagnosis, comprehensive care, and supportive resources are crucial in managing the condition. While the prognosis remains challenging, ongoing research and advances in medical care continue to offer hope for improved outcomes in the future.
