Trisomy 18 and Chromosomal Abnormalities by Benta Okello

Among three genetic disorders namely Trisomy 13 and 21, Trisomy 18 is a very rare and most severe form of genetic disorder. It is also known as Edwards Syndrome as reported by the National Institute of Health. It is a genetic anomaly that is caused by an extra copy of chromosome attaching itself to the eighteenth chromosome, thus resulting in 47 chromosomes instead of the natural 46. This description explains how this disorder came to be known as Trisomy 18. The fetus inherits a pair of 23 chromosomes from the mother’s egg and the other pair from the father’s sperm during conception. Trisomy 18 affects both females and males. According to CDC statistics, 1 out of 5000 children born with this syndrome has Trisomy 18. MedlinePlus also reports infants affected by this syndrome end up dying stillborn. And European Journal of Pediatrics reports 5 10% of patients survive the first year of life

Given the nature of this syndrome, WebMD explains that the structures of the body organs of a child born with Trisomy 18 syndrome are severely affected. Congenital defects associated with this syndrome are namely heart defects of various types such as Ventricular Septal Defect (VSD) – a hole between the lower chambers of the heart or, Atrial Septal Defect- a hole between the upper chambers of the heart, deformed lungs and liver, small head, small jaw, poor muscle tone, feeding problems, deformed feet, clenched fist, vision and hearing impairment, low birth weight, gastroesophageal reflux (backward flow of stomach content upward to the throat), compromised immune system and many others. Though the effects of this syndrome are greatly severe, much depends on the nature of the defects of every child. For example, my five-year-old son was born with one large hole in the heart while my friend’s child had three large holes in the heart even though they both have the same syndrome.

MedlinePlus reports that Trisomy 18 syndrome is diagnosed using methods recommended and offered by medical doctors to expectant mothers, commonly known as prenatal screening, also known as pregnancy screening tests, are often recommended by doctors. These types of tests help determine if the fetus is at risk of Trisomy 18 disorder.  A doctor gives a full explanation to an expectant mother of what to expect from such tests. Usually, the decision to or not to proceed with it is up to the expectant mother. The types of methods used in diagnosing Trisomy18 in a fetus are commonly an ultrasound exam and blood tests. These first two tests are carried out in the first-trimester screening between 11 and 14 weeks of pregnancy. The second type of screening test method is performed during the second trimester, is Amniocentesis, also known as Human Chorionic Gonadotropin, in which a fluid is drawn from the placenta. With this sample, the doctor is able to screen for Trisomy 18 and any neural tubal defects a fetus may have.

Once the diagnosis is made, again the decision is for the expectant mother whether to carry to full term or terminate the pregnancy. In such cases, counseling is offered if needed by the client. Otherwise, the types of treatments offered to the affected child are aimed at managing the condition since there is no cure for this disorder. Unfortunately, the prognosis is poor. However, the severity of Trisomy18 comes with multiple defects as a result of malformed structures of the organ systems of the body. These factors greatly affect the functions of the body while additionally, the patient’s immune system cannot protect the body from being attacked by infections.  A child with this condition is often sick and financially very expensive to manage.

The care involved is one on one type of care for such a child to thrive. Most of the time, admission to the Intensive Care Unit is the place a child fights for his or her life when sickness sets in. In the intensive care unit, the child is managed under very sophisticated modern medical equipment by a team of not less than ten professional medical doctors and nurses surrounding the child. According to the European Journal of Pediatrics, New York (2003), in an article entitled Intensive care in an adolescent with trisomy 18, states that breathing difficulties (acute dyspnoea) due to respiratory distress and occurrence of seizures are treated with different types of medications. These are respiratory inhalers (budesonide)  along with nebulizers, and vest airway clearance, Keppra, a medication for treating seizures, is combined with a muscle relaxer to help bring seizure and muscle spasms under control.