Cri Du Chat Syndrome

By: Grace Alvarez & Sydney Aledort

What is Cri Du Chat Syndrome?

The name Cri Du Chat is French for "cry of the cat," referring to the distinctive cry of children with this disorder. Sometimes it is also known as Chromosome 5p deletion syndrome, 5p minus syndrome, or Cat cry syndrome. The cry is caused by abnormal larynx development, one of the many symptoms associated with this disorder. It usually becomes less noticeable as the baby gets older, making it difficult for doctors to diagnose Cri Du Chat after age two.

Symptoms of Cri Du Chat Syndrome:

Babies with Cri Du Chat Syndrome usually have a small birth weight, and may have respiratory problems. Often, the larynx doesn't develop correctly, which causes the signature high pitched cat like cry.

People who have Cri Du Chat Syndrome have very distinctive features. They may have a small head (microcephaly), an unusually round face, a small jaw (micrognathia), widely set eyes that slant downward, folds of skin over their eyes, low set or abnormally shaped ears, partial webbing or fusing of fingers or toes, single line in the palm of the hand instead of two.

Several problems occur inside the body, as well. A small number of children have heart defects, muscular or skeletal problems, hearing or sight problems, or poor muscle tone. As people with Cri Du Chat Syndrome grow they usually have difficulty walking and talking correctly. They may have behavior problems (such as hyperactivity or aggression), slow or incomplete development of motor skills, and severe mental retardation. If no major organ defects or other critical medical conditions exist, life expectancy is normal.

How do people get Cri Du Chat Syndrome?

The deletion of chromosome 5 is caused by a break in the DNA molecule that makes up the chromosome. In most cases, the chromosome breaks while the sperm or egg cell (the male or female gamete) is developing. When this gamete is fertilized, the child will develop Cri Du Chat Syndrome. The parent, however, does not have the break in any other cells of the body and does not have the syndrome. The break is also so rare that it would be very unlikely to happen again if the parent has another child. It is possible for a child to inherit a broken chromosome from a parent who also had the disorder.

Can Cri Du Chat Syndrome be inherited?

Most cases of Cri Du Chat syndrome are not inherited. Affected people typically have no history of the disorder in their family. Only about 10 percent of people with this syndrome inherit the chromosome with a deleted segment from an unaffected parent. This means the parent carries a chromosomal rearrangement called a balanced translocation, which is passed to their baby, causing them to have the Cri Du Chat Syndrome.

How do doctors diagnose Cri Du Chat Syndrome?

Doctors most often identify Cri Du Chat Syndrome by the symptoms, but it is also possible to test for Cri Du Chat Syndrome (and other chromosomal abnormalitites) while the baby is still in its mother's womb. They can either test a tiny sample of tissue from outside the sac where the baby develops (chorionic villus sampling (CVS)), or they can test a sample of the amniotic fluid (amniocentesis).

Treatment of Cri Du Chat Syndrome:

Although there is no real treatment for Cri Du Chat Syndrome, children with the disorder can go through therapy to improve their language skills, motor skills, and to help them develop as normally as possible. A retardation test as the child grows can give the parents an idea of how their child compares to normal children. This will help doctors and parents identify what actions need to be taken to make the child comfortable in every day life. Counseling and help of an outside professional is highly recommended for the family because dealing with a special needs child is difficult and most parents are not prepared to treat the symptoms and conditions that go along with it. Sometimes parents may want genetic testing to determine who caused the chromosome problem, and why. Parents should consider this if they plan to have children in the future.