Powerpoint on Down Syndrome

This is a presentation that my group presented in class on Down Syndrome. Here is the information from the powerpoint:

History of Down Syndrome (DS)

• Evidence dating back to the 7th century A.D. that showed physical features of an individual with Down Syndrome. 
• Portrait paintings from the 1500’s that displayed children with a Down Syndrome-like facial appearance. 
• Dr. John Langdon Down in 1866 published the first complete physical description of Down Syndrome.
• Researchers identified the chromosomal abnormality that causes Down Syndrome in 1959.

Prevalence

• 13.7 per 10,000 births 
• Maternal age is linked to Down Syndrome.
• Trisomic Down Syndrome occurs more in males. (59% males and 41% females) 
• Translocation Down Syndrome occurs more in females. (74% females and 26% males) 
• *The etiology of this is unknown.

 At age 20 the prevalence is 1 in 2,000 and at age 45 the prevalence is 1 in 20. (trisomy 21)

No increased risk if there is an increase in maternal age if it is the translocation abnormality.

1/3 of persons with the translocation down syndrome inherit it from a parent who is a carrier. Chromosomal analysis can ID people that are carriers of the translocation.

Early Intervention

•  Women that are 35 years + are offered prenatal diagnostic testing for DS. (during 1st and 2nd trimesters).
• Genetic counseling 
• Easily ID at birth
• Genetic counseling- if the pregnancy is continued then cardiac planning parental accommodations and appropriate medical evaluations of the infant is provided.
• Easily ID at birth because of the physical features present.

Most Common Characteristics of DS

• 3 palm print patterns.
• Brush field spots (colored speckles in the eye lid of the eye)
• Ear length 
• Neck skin fold 
• Widely spaced first toes

 Chromosomal Findings

• Trisomy 21 (95% of individuals with Down Syndrome)
• Translocation (4% of individuals with Down Syndrome)
• Mosaicism (1% of individuals with Down Syndrome)

 Trisomy 21 is a result of a nondisjunction usually in meiosis 1 of the egg.

Translocation is the attachment of the long arm of an extra chromosome 21 to chromosome 14, 21, or 22.

Mosaic Trisomy is when some but not all cells have the defect. This is usually from nondisjunction during mitosis of the fertilized egg.

The only difference in children with Mosaic Down Syndrome is that they typically score higher on IQ test.

Chromosome 21

• Sequencing on this chromosome contains more than 400 genes.
• The sets of genes located on this chromosome are involved in specific metabolic pathways and biological systems.

Ex. Of sets of genes located on chromosome 21: 10 genes influence the structure and function of the CNS.

Overexpression of one of the genes might result in early onset of Alzheimer’s in individuals with Down Syndrome.

Malformations caused by Trisomy

• Incomplete rather than deviant development of the embryo.
• Atrial septic defect, or ventrical septic defect.
• Tracheoesphogeal fistula 
• Brain tissue in individuals with Down Syndrome can have multiple developmental abnormalities.

 ASD-VSD is when the heart is normally formed by the walls separating the two sides of the heart may not close completely

TF- the separation of the trachea and the esophagus may be incomplete.

Brain Tissue Abnormalities include-delayed myelination, fewer neurons, decreased synaptic density and decreased acetylcholine neurotransmitter receptors.

Medical Complications

•   Congenital Heart Defects (endocardial cushion defect, ventricular septal defect, artrial septal defect)
• Sensory Impairments (vision and hearing problems)
• Overweight (sometimes leads to a metabolic syndrome)
• Short Stature 
• Orthopedic Problems (atlantoaxial subluxation, partial dislocation of upper spine, torticollis, and juvenile rheumatoid arthritis)
•  Dental Problems (periodontal disease & malocclusions)
• Gastrointestinal Problems
• Epilepsy
• Hematologic Disorders
• Skin Conditions

 Gastronintestinal problems include symptoms in newborn poor feeding, vomiting, or aspiration pneumonia. GERD is known to be common in children with DS. Esophagealatresia an abnormal connection between the trachea and the esophagus. Celiac disease has been found in 1%-7% of children with DS.

Epilepsy 6% is more common in DS than in general population………..55% of all seizures are tonic-clonic, 13% infantile spasms

Seizures most common in in <3y/o

62% of all seizures have an identifiable cause; most common are: infections and hypoxia resulting from congenital heart dz.

Hematologic Disorders almost every cellular element of hematopoietic (blood) system has been found to be at risk for abnormality in DS

A complete blood count is indicated at birth for infants with DS

Few abnormalities lead to serious problems

1 in 150 children with DS will develop either acute myelognous leukemia or acute lymphoblastic leukemia during their lifetime

Skin Conditions by puberty ½ of all ind. Will expereince atopic dermatitis (eczema), chelltis (inflammation of the lips), ichtyosis 
 
Neurodevelopment and Behavior

•  Hypotonia and associated delayed gross motor development.  
• First 2 years of life: appear to have less cognitive impairment (compared to later in life) 
• By 2 years of age: significant language delays are evident. Receptive language is better than expressive. 
• 85% of children with DS have IQ scores that range from 40-60 (mild-moderate intellectual disability)

 *hypotonia & delayed gross motor development: most children with DS don’t sit up until 11 mos, don’t walk until 19 mos…developmental milestones in boys with DS are usually reached slightly later than girls with DS

*2 years (significant language delays are evident): children w/ DS don’t speak their 1st word until 18 mos of age…even when children w/ DS speak in sentences, problems w/ intelligibility interfere w/ effective communication…THEREFORE, speech tx focuses on expressive language and intelligibility for many years

*psychology testing (85% of children with DS): even though these children generally have poor verbal short-term memory skills, their visual-motor skills are relatively STRONG!

*behavior: study discussed that 29% of children with DS have behavior or psychiatric disorders, such as, aggressive behavior, ADHD, oppositional disorder, stereotypic behavior, elimination difficulties, ASDs, and Tourette syndrome….2nd study discussed children with DS having ASDs…some ind. with DS experience deterioration of cognitive or psychological function in adolescence, which manifests in worsening behavior…could be attributed to unrecognized hypothyroidism or depression…adults with DS can also have a decline in function, such as, mental health disorders (anxiety, depression, or obsessive-compulsive disorder…more than ½ …Alzheimer’s counts for 1/5th)

Medical Evaluation

•  First 6 months of life, all children with DS need an ophthalmologic evaluation. 
• Infants with DS who fail their newborn hearing screen will need a hearing evaluation by 3 months of age.
• Polysomnogram should be performed there is suspicion of sleep apnea.
• Infants with DS need to be screened for congenital hypothyroidism, and receive thyroid function tests at 4-6 months of age, at 1 year, and annually thereafter.
• Should be screened for celiac disease at 30 months of age.
• Children with DS should have their growth monitored.
• Daily cleaning of teeth should begin as soon as their teeth come in. 
• Evaluation of children for atlantoaxial subluxation by X-ray studies is usually done on entrance to preschool and sometimes prior to elective surgery. 
• Screenings for diabetes and leukemia are not routinely done, it is appropriate to lower the threshold for evaluation for individuals with DS

Medical Treatment

• Parents of a newborn with DS should be provided with a balanced view of the condition.  
• Up-to-date print materials on infants with DS. 
• Early intervention programs are needed for children with DS. 
• Educational program of a child with DS should provide the optimal environment for learning.
• A visual approach should be used with children with DS. 
• Alternative and complementary therapies to improve cognitive function and appearance. 
• Study: adults with DS treated with donepezil show improvement in language and dementia scores

Prognosis

• Prognosis for a productive and positive life experience for individuals with DS has increased substantially from the 1970s .
• Children with DS were the first children with disabilities to be “mainstreamed” into public schools.
• Life expectancies have improved since 1980s, more than half of individuals with DS will survive into their 50s, and that 13.5% will be alive at age 68 years.
• Introduction of supported employment (1980s) has allowed adults with DS to hold jobs with improved pay and benefits, and better working conditions.

Reference:
Batshaw, M. (2007). Children with disabilities. (6th Edition). Baltimore, MD: Paul H Brookes. p 263-271

Posted by: Anna Bryant