Down Syndrome Information
The first disorder attributed to a chromosomal aberration, Down syndrome (also known as mongolism and trisomy 21 syndrome) characteristically produces mental retardation, abnormal facial features, and other distinctive physical abnormalities. It's commonly associated with heart defects and other congenital disorders.
Life expectancy and quality for patients with Down syndrome have increased significantly because of improved treatment of related complications and better developmental education programs. Nevertheless, up to 44% of Down syndrome patients who have congenital heart disease die before they're 1 year old.
Down syndrome is the most common genetic cause of severe learning disabilities in children, occurring in one in every 800 infants. Every year, as many as 5,000 babies are born with Down syndrome in the United States.
Down syndrome usually results from trisomy 21, an aberration in which chromosome 21 has three copies instead of the normal two because of faulty meiosis (non-disjunction) of the ovum or, sometimes, the sperm. This results in a karyotype of 47 chromosomes instead of the normal 46.
Although the incidence of non-disjunction increases with maternal age, the extra chromosome originates from the mother only 80% of the time. Studies suggest that in some cases, the chromosomal abnormality results from deterioration of the oocyte. Such degeneration can be caused by age or the cumulative effects of environmental factors, such as radiation and viruses. About 4% of the time, Down syndrome results from an unbalanced translocation in which the long arm of chromosome 21 breaks and attaches to another chromosome.
Individuals with Down Syndrome may not experience all of the symptoms. Some of the common symptoms are: decreased muscle tone at birth, asymmetrical or odd-shaped skull, round head with flat area at the back of the head, small skull, slanting eyes, small mouth with protruding tongue (see tongue problems), broad short hands, single crease on the palm, retarded growth and development, delayed mental and social skills (mental retardation).
Tests can be done before birth to find out if a baby has Down syndrome. Tissue and fluid in the womb around the baby can be checked for the extra chromosome. After birth, if the baby has any of the physical signs or birth defects of Down syndrome, the baby's blood can be tested to check for the extra chromosome.
Additional medical tests confirm the presence of associated conditions. Developmental screening tests, such as the Denver Developmental Screening Test, determine the severity of retardation and chart the patient's progress in response to intervention or education programs.
Surgery to correct cardiac defects and other related congenital abnormalities, antibiotic therapy for recurrent infections, and thyroid hormone replacement for hypothyroidism have improved life expectancy considerably for patients with Down syndrome. Plastic surgery may correct the characteristic facial traits, especially the protruding tongue, cleft lip, and cleft palate. Benefits beyond improved appearance may include improved speech, reduced susceptibility to dental caries, and fewer orthodontic problems later.
When possible, parents of Down syndrome children are encouraged to keep their children at home rather than in an institution. Early intervention (such as infant stimulation programs) increases sensory awareness and has proved helpful with some patients. Special education programs, mandated in most communities, permit the child to maximize his potential and promote self-esteem. His physical condition and self-image also can benefit from special athletic programs. As adults, many Down syndrome patients become productive workers at jobs that match their intellectual abilities.
Genetic counseling is recommended in all families with Down syndrome. Down syndrome can be detected in a fetus in the first few months of pregnancy by examination of the chromosomes obtained by amniocentesis or chorionic villus sampling. The parents of a child with Down syndrome are at increased risk for having another child with Down syndrome. Mothers who become pregnant after age 40 are also at increased risk for having a child with Down syndrome.
Disclaimer: thedepressiontreatment.com is designed to help and support for people who have depression or are depressed. It is not intended to treat, diagnose, cure, or prevent any psychiatric, psychological or mental diseases. Always take the advice of professional health care for specific medical advice, diagnoses, and treatment. We will not be liable for any complications, or other medical accidents arising from the use of any information on this web site.