How to Diagnose Trisomy 13

Sometimes referred to as Patau syndrome, Trisomy 13 occurs when a child is born with an extra thirteenth chromosome present in some or all of his cells. Though the disorder causes severe physical and cognitive abnormalities and disabilities, it is possible for affected patients to survive into adulthood. Read on to learn how to diagnose Trisomy 13.

Instructions

Difficulty: Moderately Challenging

1. Have your physician diagnose Trisomy 13 pre-natally, if possible. This will give you time to prepare for the arrival of your special-needs infant. If ultrasound images are showing that your baby's organs are rotating abnormally, you should seek further testing for Trisomy 13.
2. Get a magnetic resonance imaging (MRI) or computed tomography (CT) scan performed on your unborn baby. Your doctor will look for a condition called "holoprosencephaly," in which the two hemispheres of the baby's brain grow merged together as one. From there, your doctor may have enough information to diagnose Trisomy 13, or further tests may be performed.
3. Ask for a karyotyping test to be performed. These chromosome tests draw samples from fluid in the uterus, umbilical cord or placenta to be tested for the presence of an extra thirteenth chromosome. A conclusive diagnosis can usually be drawn at this point.
4. Know that your obstetrician will take notice if your baby is born with a single umbilical artery. This is an abnormality that often signals the presence of a congenital heart defect. Because Trisomy 13 causes developmental heart defects, it will be suspected. A chromosomal test will likely be ordered by your doctor to determine the cause of the defect(s).
5. Recognize the symptoms of a child with undetected Trisomy 13. Pronounced mental retardation occurs. Seizures and a host of physical defects--including a small head, eye malformations, extra fingers and absent skin on the scalp--also accompany the development of a Trisomy 13-positive patient. Ask your doctor to diagnose the cause of any such problems at the first sign of their presence.

Tips & Warnings

• Trisomy 13 has a recurrence rate lower than that of Down syndrome and many other congenital disorders. Parents of a baby affected by Trisomy 13 have less than a one percent chance of conceiving a second Patau syndrome child.
• Infants affected by Trisomy 13 are not expected to survive. Eighty-five percent of children born with the condition do not live past their first birthday. It is extremely rare for children with the condition to survive until age 10.