Trisomy 13 Life Expectancy

Trisomy 13 Life Expectancy

Trisomy 13 or Patau syndrome is a genetic disorder in babies with three copies of the genetic material in the thirteenth chromosome. While healthy babies have two copies of genetic material in the thirteenth chromosome. The issue can affect the development of the baby in many ways. Keep reading to learn more about factors that may affect life expectancy in this condition.

Trisomy 13 Life Expectancy
While the condition is quite rare, you can still find babies born with it. The disorder can lead to serious mental and physical abnormalities including heart defects. Many babies with Patau syndrome are stillborn or die within the first few days after being born.It is hardtopredictthe life expectancy if the baby does not have any immediate life-threatening problems.

• About 50% of babies die within the first week of their birth.


• 90% die within a year.


• Only 5-10 % manage to live longer than a year.

Is There Any Treatment for Trisomy 13?
Unfortunately, there is no standard treatment available for babies born with this disorder. It is therefore difficult to improve Trisomy 13 life expectancy. Healthcare providers focus their treatment on improving symptoms only. Many children with this disorder eventually need surgery as well as occupational therapy, speech therapy, physical therapy, and other supportive treatment measures.

Some infants born with incurable birth defects, but some respond well to treatment used to correct structural abnormalities. Special formulas, techniques, and positions are used to deal with feeding problems. The placement of a gastric tube may help in this regard. Surgery is the only treatment option to correct structural abnormalities such as cleft palate and cleft lip. The combination of hearing Aids, special diets, and vision aids may help deal with other symptoms of Patau syndrome.

Causes and Symptoms of Trisomy 13
Causes
While Trisomy 13 is a genetic disorder, it does not pass from the parents to the child. It mainly happens due to defects in the sperm or the egg that forms the fetus. Under normal circumstances, egg and sperm unite and form 23 pairs of chromosomes. In rare cases, egg and sperm form an extra chromosome and the chromosome 13 is released to the embryo. Both mother's egg cell and father's sperm cell can give that extra chromosome to the embryo.

There are three types of this disorder, and these types also have some impact on the overall Trisomy 13 life expectancy.

• Full Trisomy: In this condition, every cell in the body of an affected baby has an additional copy of chromosome 13.


• Partial Trisomy: In this condition, patients do not have a full extra copy of chromosome 13, and only an extra part of the chromosome attached to some other chromosome in the cells.


• Mosaic: Patients with this type of disorder have an entire extra copy of chromosome 13, but they are not present in some of the body's cells.

Symptoms
The symptoms usually depend on the severity of the condition. In addition, the symptoms may be different when only some of the cells are affected–it means the type of Trisomy 13 will also have an impact on how severe the symptoms are.

The most common symptoms include cleft palate, close-set eyes, cleft lip, clenched hands, extra fingers, impaired muscle tone, low-set ears, hernia, skeletal deformities, impaired mental development, and seizure. Some patients may also have a small lower jaw, small head, and un-descended testicles.

How Is Trisomy 13 Diagnosed?
A physical exam is usually all that is required to diagnose Trisomy 13. An affected baby will have certain physical characteristics and symptoms as mentioned already, which makes it easy for doctor to diagnose. Still, they may order a blood test to analyze the chromosomes to confirm the presence of chromosome 13.

It is also possible to analyze cells in the amniotic fluid to confirm the presence of chromosomal abnormalities. The fluid is usually obtained from the placenta through chorionic villus sampling (CVS). A detailed fetal ultrasound may also help make a diagnosis, but it is not a very reliable way. A chromosome analysis is usually 99.9% accurate.

How Often Does Trisomy 13 Occur?
It is quite a rare disorder and affects only 1 in 16,000 newborns in the US. The risk of having a baby with this disorder increases with the age of mother, but a woman can give birth to a baby with Trisomy 13 at any age.

Trisomy 13

Trisomy 13






Patau syndrome is a disorder developing due to abnormal chromosomes inherited by birth. Presence of extra genes in chromosome number 13 is known as Patau syndrome or Trisomy 13. Children born with this syndrome would have severe mental dysfunction in addition to physical abnormalities. Extra number of chromosome is present in all the cells when the baby is formed causing severe intellectual and physical problems. Such children would have birth defects in the heart, brain and various other vital organs due to unwanted chromosome distribution in the entire body cells. Exact cause of Patau syndrome is not known and there is no cure for this disorder.

Symptoms :

Children born with Patau syndrome will have marked physical problems from eyes to foot. They would be born with defective heart, defective spine and underdeveloped eyes. Brain would have serious anatomical defects and it may not divide properly. There would be a cleft lip (small opening) along with cleft palate (small opening in the mouth). The muscle tone will be very weak leading to hypotonia.

The baby may have extra finger in hands and foot. Owing to the various physical problems these infants would be stillborn or may get aborted in the uterus. In rare cases only the baby survives birth but may live only for few weeks. In addition to the above physical abnormalities such children would have severe intellectual impairment.

How common is it?

Patau Syndrome or Trisomy 13 is very rare disorder. Statistics say that one out of 16,000 births would be of this syndrome.

Risk Factors :

Women having close relatives infants born with Patau syndrome are at risk of passing on the disorder to her baby. Women who give birth after 35 years have slight risk of developing genetically abnormal baby.

Causes :

Patau syndrome is a genetic disorder. The affected child would have 3 identical copies (hence the name Trisomy) of chromosome 13 (instead of 2) in each and every cell of the body. Extra genetic material would have been migrated during the formation of chromosome 13 from another part leading to Trisomy 13. This may occur as and while fusion takes place between the eggs and sperm forming a zygote.

The parents of such an offspring would contain no extra chromosome number 13 but normal copies of it. In rare cases part of 13 no. chromosome is seen in all the three copies and such babies would not have many abnormalities as Trisomy 13. Here the extra chromosome is found in only some of the body cells and such cases are referred to Mosaic trisomy 13.

How this happens?

Exact cause of attachment of extra genetic material on chromosome 13 is not understood. Often Patau syndrome occurs as random events that happen during the formation of zygote. The parents of such babies would be healthy but error may occur during cell division causing the zygote with abnormal chromosome. Either the egg cell or sperm may get one extra copy of chromosome leading to Trisomy 13. If the genetic composition of the baby is made of such atypical reproductive cell then the developing fetus would have one extra chromosome in each cell of his/her body.

In some cases Patau syndrome can be inherited due to translocation of genetic components. A healthy father/mother may carry rearranged set of genes in chromosome 13 or some other chromosomes. During reproduction such rearranged chromosome is used for the formation of zygote thus passing extra genetic substance in each cell. A person with carrier gene is at high risk of producing Trisomy 13 children.

Images, Pics, Photos and Pictures of Trisomy 13 (Patau syndrome) :

Diagnosis :

Infants born with Patau syndrome can be easily identified. Genetic abnormalities can be found even during first/second trimester of pregnancy. Chromosome testing can be done to confirm the diagnosis.

Treatment :

There is no cure for Patau syndrome. Most of the cases with this syndrome will not survive birth and even if they survive the fetus would live for only few weeks. Supportive oxygen can be given for such babies with Patau syndrome but often life supporting measures are not useful. Parents can be given counseling during and after childbirth. If any one of the parents is found to have translocated chromosome counseling should be given to prevent future pregnancies. Other family members would also be screened for chromosomal problem.

Prognosis :

Rate of survival is very low and limited for infants with Patau syndrome. Patau, an American scientist first described this disorder in 1960 and hence the name Patau Syndrome.