Mental Retardation

            Down syndrome is the most frequent hereditary cause of mild to moderate mental retardation and associated medical problems that occurs in one out of one thousand births. People born with Down syndrome have recognizable physical characteristics and limited intellectual gifts which are due to the presence of an extra chromosome twenty one. There are several other medical conditions such as hearing loss, heart disease, and vision disorders, which are common among those with Down syndrome. Children often are the most susceptible to this disease and have a greater chance of developing health related problems.
             Studies indicate that sixty six to eighty nine percent of children with Down syndrome have a hearing loss in at least one ear, due to the fact that the external ear, the bones of the middle and inner ear may develop differently in children with Down syndrome. In addition to hearing disorders, visual problems also may be present at the early stage of childhood. Cataracts occur in approximately three percent of children with Down syndrome; however it can be surgically removed if found at an early age. Approximately half of the children with Down syndrome have inherited heart disease and associated early and high blood pressure in the lungs. .
             Zachwieja 2.
             Seizure disorders, though less common than some of the other associated medical conditions, still affect between five and thirteen percent of individuals with Down syndrome. There is an unusual occurrence of non fatal spasms or seizures in children less than one year of age; luckily in most cases these seizures can be treated with anti-epileptic drugs. Infants with Down syndrome are also more susceptible to transient myelodysplasia, or the defective development of the spinal cord. Also during the early years of childhood, children with Down syndrome are ten to fifteen times more likely than other children to develop leukemia, a potentially fatal disease.