Down Syndrome

WHAT YOU SHOULD KNOW

Down syndrome is a congenital disorder that results in varying degrees of both mental retardation and physical abnormality. Normal growth and development is stunted, and most affected children never reach full adult height. Their mental age rarely surpasses that of an 8-year-old. Down syndrome children are known to be very affectionate and happy. They usually fit in well with families that offer them a lot of emotional support and mental stimulation.

Causes

Down syndrome results from an extra chromosome in each of the body's cells. Normally, the cells have 46 chromosomes (23 pairs); in a child with Down syndrome the total is 47. Ninety-five percent of all Down syndrome cases are classified as trisomy 21 because the extra chromosome is attached to the 21 ^st pair. In a few cases, the excess chromosome is found elsewhere. The reason for this chromosomal abnormality remains unknown.

A woman's chance of giving birth to a child with Down syndrome increases with age. In the early childbearing years, the odds of having a Down syndrome child are only 2000 to 1. After age 40, the risk rises to 40 to 1. The parents of a child with Down syndrome are at increased risk of having other children with the condition.

The condition can be detected during the first few months of pregnancy by evaluating the chromosomes in the amniotic fluid that surrounds the baby. To do this, the doctor withdraws a sample of the fluid with a needle pushed through the abdominal wall. The procedure, called amniocentesis, is usually conducted during the 15 ^th or 16 ^th week of pregnancy.

Signs/Symptoms

Down syndrome children are easily recognized. The head may be smaller than normal and abnormally shaped. Prominent facial features include a flattened nose, a small mouth with a protruding tongue, and upward slanting eyes. The hands are short and broad, with short fingers and a single crease in the palm.

These children are also prone to heart problems, and to obstruction of the digestive tract, which may lead to severe vomiting. Outward symptoms include decreased muscle tone at birth, a flat area on the back of the head, and an abnormality in the colored part of the eye called Brushfield's spots.

There are several tests your doctor can perform shortly after birth to determine whether a child has Down syndrome. For example, listening to the chest with a stethoscope may detect a heart murmur, and an unsuccessful attempt to pass a tube from the nose into the stomach may reveal an obstruction in the esophagus. The most common diagnostic tests include:

• A physical exam (performed if Down syndrome is suspected due to physical abnormalities
• Chromosome studies to confirm the presence of three 21-chromosomes;
• A chest x-ray to determine the presence of heart abnormalities
• An echocardiogram to determine the nature of the cardiac abnormality
• A gastrointestinal x-ray to search for an obstruction

Care

There is no cure for Down syndrome. However, carefully monitoring the child's health can reduce the likelihood of the complications to which these kids are susceptible.

In general, the goal of the care is two-pronged: to prevent further physical problems and to promote mental acuity and motor skills as much as possible. Today, there are a number of resources you can turn to for help with this task, and special education for the mentally handicapped is available in most communities.

If the condition is accompanied by certain heart defects, surgical correction may be necessary. Obstructions in the digestive system may also call for major surgery shortly after birth. Visual problems, hearing loss, and increased susceptibility to infection require screening and treatment at appropriate intervals, which vary from child to child.

Risks

Heart problems are a major concern, often resulting in early death. Leukemia is another common danger. And it's important to stay alert for signs of infection.

WHAT YOU SHOULD KNOW

A healthy diet and plenty of exercise and mental stimulation will help the child lead a more fulfilling and comfortable life. Here are a few general recommendations for improving overall health and avoiding the illnesses commonly associated with Down syndrome:

• Work closely with your healthcare providers to evaluate the child's need for special education and physical therapy. The need for work on physical problems varies.
• Make sure that the child gets some form of exercise each day. For example, walking briskly for 30 to 60 minutes three to five times per week is an excellent form of exercise for Down children.
• Provide a diet high in fiber and low in fat, salt, and cholesterol.
• Have blood pressure, cholesterol, and blood sugar levels checked regularly. High readings increase the risk of heart disease.
• Keep the child's environment clean, comfortable, and free of air-borne irritants. Smoke, dust, molds, perfumes, and pollen are just some of the irritants that can contribute to respiratory distress and increase the chance of infection. An air purifier can help keep the child's room cool, dry, and smoke-free.
• Make sure the child wears ear protection when around loud noises, such as fireworks or any type of explosives, and never put anything into the ear.
• For more information, contact the National Down Syndrome Society at 516-221-4700.

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