Down syndrome is a genetic condition caused by the presence of an extra chromosome 21. It causes delays in physical and intellectual development. The document discusses the history, causes, signs and symptoms, diagnosis and prognosis, treatment options, complications, prevention strategies, management approaches, and outcomes of Down syndrome. Early intervention, screening for common health issues, addressing medical needs, and providing a supportive family environment can help improve development for those with Down syndrome.

1. Presentation topic
A review study on
pathophysiology and treatment of Down
Syndrome disease 1

2. Presenting By
Md Sezan Biswas
ID: PG12-25-22-028
Batch: 25th (B)
2

3. What is Down Syndrome ?
• Down syndrome is perhaps the oldest condition associated with mental
retardation and the most common genetic cause of developmental
disability.
• Down syndrome also called Trisomy 21, is a genetic condition that causes
delays in physical and intellectual development.
• It is a chromosomal disorder caused by an error in cell division & there is
extra genetic material from chromosome 21, so individuals with Down
syndrome have 47 chromosomes in total instead of the usual 46.
3

4. History
• English physician John Langdon Down first described Down syndrome in
1862, recognizing it as a distinct type of mental disability, and again in a
more widely published report in 1866. Described as Mongoloid child of
European parentage-”Mongolism”
• In 1959 a French doctor, named “Jerome Lejeune”, discovered it was
caused by the inheritance of an extra chromosome 21.
• Also known as “trisomy 21”
4

5. Etiology & Pathophysiology
• Down syndrome is usually caused by an error in cell division called
nondisjunction.
• During meiosis, one pair doesn’t divide & the whole pair goes to one daughter
cell. In the resulting cells, one will have 24 chromosomes & the other will have
22.
• So if a sperm or egg with an abnormal of chromosomes merges with a normal
mate, the resulting fertilized egg will have an abnormal # of chromosomes.
• In Trisomy 21, one cell has two 21st chromosomes instead of one, so the
resulting fertilized egg has three 21st chromosomes. 5

6. Signs And Symptoms
• Flat appearing face
• Small head.
• Small mouth, which causes the tongue to stick out and to appear overly
large.
• Upward slanting eyes.
• Rounded cheeks.
• Weak, Floppy muscles(hypotonia).
• Small, misshapen ears.
6

7. Signs And Symptoms
• Small, wide hands
• An unusual, deep crease across the center of the palm (called a Simian
Crease)
• A malformed fifth finger.
• A wide space between the big and the second toes.
• Unusual creases on the soles of the feet. Overly flexible joints.
• Shorter than normal height.
7

8. Diagnosis & Prognosis
• Usually suspected at birth. Genetic testing (chromosome analysis) is done
to verify the presence of the disorder. Pregnant women be offered
screening with the option for invasive diagnostic testing for DS, regardless
of age.
• Chorionic Villus Sampling (CVS): sample of placenta taken either through
the cervix or through a needle inserted through the abdomen.
• Amniocentesis: Removal of a small amount of amniotic fluid through a
needle inserted in the abdomen. Cells are analyzed for the presence of
chromosomal abnormalities. Test performed between 12 and 20 weeks of
pregnancy. 8

9. Treatment & Therapies
• People with Down syndrome are at increased risk for certain medical problems.
Some of the problems commonly faced by people with Down syndrome include
heart defects, thyroid, muscle, joint, vision and hearing problems.
• Other conditions seen less frequently in Down syndrome include leukemia, and
seizures.
• Medications can be used to treat certain conditions that occur in people with
Down syndrome. For example, if a person with Down syndrome has a seizure
disorder, they would benefit from taking anti-seizure medications.
9

10. Treatment & Therapies
• People with thyroid problems often take thyroid replacement hormones. While
these medications help with their medical condition, they do not have any effect
on their Down syndrome. At this point in time, there is no medicine that will cure
Down syndrome.
• Some medical conditions seen in children with Down syndrome require surgery.
For example, about 40% of children with Down syndrome have congenital heart
defects. Some of these defects are mild and may fix themselves, and some heart
defects are more severe and will require surgery. Children with Down syndrome
can have intestinal defects that also require surgery. 10

11. Types of Down syndrome
• Trisomy 21 (95%): The extra 21 chromosome (three instead of the usual
two) produces a complement of 47 chromosomes.
• Translocation (3-4%): A segment of a 21 chromosome is found attached to
other pairs of chromosomes.
• Mosaicism (1-2%): Nondisjunction occurs at a later stage of cell division,
therefore, some cells have the normal complement of 46 chromosomes
and other cells 47 chromosomes (with an extra 21 chromosome).
11

12. Risk factors
• Women who are 35 years or older are at the greatest risk for giving birth to
an infant with Down syndrome.
• 35 years: 1/400 live births & > 40 years: 1/110 live births
• According to the CDC, younger mothers (< 35 years) who smoke, use oral
contraceptives, and have a Meiotic II error are at an increased risk as well.
• Despite many years of research, advanced maternal age has been the only
one factor that is well established with Down syndrome .
12

13. Complications
• According to the NICHD (Eunice Kennedy Shriver National Institute of
Child Health and Human Development) , 95% of individuals with DS
have mild to moderate mental retardation.
• Delayed language, social, & motor development
• Growth retardation
• Congenital heart disease (50%)
• Atrial or Ventricular septal defect
• Respiratory infections
• Pneumonia
13

14. Complications
• Hearing loss ( > 60%)
• GI blockages/problems
• Esophageal atresia, Duodenal atresia, Celiac disease
• Thyroid dysfunctions
• Sleep apnea (50%-75%)
• Increased risk for Dementia
• Higher risk for ALL (Acute Lymphocytic Leukemia)- (1/150)
• Vision problems
14

15. Prevention & Education
• No prevention for DS
• Absolutely nothing that anyone can do to prevent a trisomy & there is
nothing that anyone can do to cause a trisomy.
• Efforts of prevention are aimed at genetic counseling of couples who are
preparing to have babies.
• Teach parents the importance of food & fluids to maintain adequate
nutrition. Emphasize the need to balance adequate nutrition. Poor feeding
can result in obesity later in life. 15

16. Prevention & Education
• Teach family how to prevent physical complications
• Increase fiber in diet to avoid constipation
• Encourage physical activity
• Advise parents to seek regular checkups for their child
• Early intervention is the key
• Physical therapy: teach gross & fine motor movement skills
• Speech therapy: help improve language skills
• Occupational therapy: develops & master skills for independence
16

17. Management
Efforts such as early childhood intervention, screening for common
problems, medical treatment where indicated, a good family environment,
and work-related training can improve the development of children with
Down syndrome. Education and proper care can improve quality of life.
Raising a child with Down syndrome is more work for parents than raising
an unaffected child. Typical childhood vaccinations are recommended.
17

18. Genetic Counseling for Down Syndrome
Genetic counseling is basically an art of providing information about a
particular genetic condition to the concerned family in a nondirective,
truthful and empathetic manner, to promote their understanding about that
problem, to facilitate acceptance and making the best possible adjustments to
the disorder, to choose a course of action which seems to them appropriate in
view of their risk, and their ethical and religious standards, and to act in
accordance with their decision.
18

19. Mortality
• Average life span is 25yrs. To 50 yrs.
• Most likely cause of death is CHD, AAI, Hypothyroidism and Leukemia.
Improved survival is because of increased placements of infants in
rehabilitation homes and changes in treatment for common causes of
death.
• Survival is better for males.
19

20. Other Information
• People with down syndrome live up to about 50 years old.
• In 90% of Trisomy 21 cases, the additional chromosome comes from the
mother's egg rather than the father's sperm.
• Down syndrome affects 1 out of every 800 to 1,000 babies
• The life expectancy for people living with Down syndrome continues to
increase.
20

21. Conclusion
Till date, no magic bullet has been developed to improve the cognition in
these children, but an effective early stimulation therapy, behavioral
intervention, positive home environment, education and vocational training
of children with Down syndrome are helpful in improving the overall
functioning and productivity of these children. Timely monitoring and early
recognition of medical problems can decrease the overall morbidity and
results in better outcomes. Good counseling skills are required for delivering
the news to the parents. Accurate and latest information must be provided in
a supportive and empathetic manner.
21