Down Syndrome

Question 1

Chromosomal Abnormalities:

Answer 1

D own syndrome (trisomy 21) Edwards syndrome (trisomy 18) Patau syndrome (trisomy 13) Turner syndrome (45, X) Klinefelter syndrome (47, XXY)

Question 2

Risk of Recurrence:

Answer 2

v Recurrence in non-disjunction
-If a mother has affected baby with down then the recurrence
risk in next baby is: Normal Risk for the age + (1%).
v Recurrence in translocation
-If the mother is a 14:21 translocation, her recurrence risk is 15% -If the mother has a 21;21 translocation, her recurrence risk 100%

Question 3

Hx of sleep apnea

Answer 3

Symptoms of sleep apnea, including snoring, restlessness during sleep, difficulty awaking, daytime somnolence, behavioral changes, and school problems

Question 4

Skull & eye ‘

Answer 4

Skull:
• Mild microcephaly • Brachycephaly(short
anteriorposteriorly) • Wide posterior fontanel (at birth) • Large anterior fontanel • Fine silky hair
Eyes:
• Upward-slanting palpebral fissures • Epicanthal folds • Ocular hypertelorism • Brushfield spots

Question 5

Cardiovascular Problems

Answer 5

Almost half of all children with DS have congenital heart diseases 50%of cases, including :
• Atrioventricular canal (endocardial
cushion defect). • Ventriculoseptal or atrioseptal defects. • Valvular disease. • Patent ductus arteriosus. • Obstructive sleep apnea. • Pulmonary hypertension.

Question 6

Neurological Problems

Answer 6

• Muscle hypotonia. • Early onset of Alzheimer’s disease , strokes
and basal ganglia damage. • Increase risk of developing epilepsy. • Varying levels of intellectual disability. • Autism spectrum disorder. • ADHD.

Question 7

Gastrointestinal Problems

Answer 7

• Duodenal atresia a congenital
malformation with complete occlusion or
absence of the duodenal lumen. • Annular pancreas abnormal rotation of the
ventral bud of the pancreas around the
foregut during embryonic development. • Megacolon dilation of the colon in the
absence of a mechanical obstruction • Hirschsprung disease an inherited
condition that affects the large intestine
(colon) and causes problems with passing
stool. • Tracheoesophageal fistula. • Anal atresia. • Celiac disease.
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Question 8

Genitourinary Tract Problems

Answer 8

• Renal malformations • Hypogenitalism (micropenis or small
scrotum and testes) • Hypospadias. • Cryptorchidism • Delayed and incomplete puberty may
occur.

Question 9

Hematological Problems

Answer 9

Children with Down syndrome have an increased risk of developing leukemias, including : • Acute lymphoblastic leukemia (ALL). • Acute myeloid leukemia (AML).
Another hematologic abnormality, polycythemia, is common in the newborn period.

Question 10

Screening tests (prenatal)

Combined test (first trimester ) (11–13 weeks)

Answer 10

A- Maternal serum : ↑ Beta human chorionic (β-hCG) ↓ Pregnancy-associated plasma protein A (PAPP-A) B- Ultrasound
amount of fluid collecting behind the neck
clinodactyly
• Nuchal translucency increases due to the large
• Short neck, thickened nuchal fold • Absent or hypoplastic nasal bone • Shortened middle phalanges of the fifth digits with
• Shortened long bones( humerus, femur)

Question 11

Screening tests (prenatal)
2- Quadruple test (second trimester) (15–18 weeks)

Answer 11

• ↓ Free estriol • ↓ Alpha-fetoprotein (AFP) • ↑ Inhibin A • ↑ β-hCG

Question 12

Screening tests (prenatal)
3- Cell-free fetal DNA (10–20 weeks):

Answer 12

fetal DNA is isolated from a maternal blood specimen and evaluated for chromosomal abnormalities
• Noninvasive (for the fetus) but expensive test • More predictive in women with a high risk • The test is currently available but not guideline-recommended.

Question 13

confirmatory test (prenatal)

Answer 13

Fetal karyotyping Indications
• Positive screening test • Previous trisomy 21 pregnancy • Parent with known chromosomal translocation or aberration
Procedures 1- Chorionic villus sampling (9–14 weeks) 2- Amniocentesis (15–22 weeks) 3- Percutaneous umbilical cord sampling (18–22 weeks)

Question 14

Postnatal diagnostics

Answer 14

• Chromosome analysis • Screening for associated conditions e.g., echocardiography to detect heart defects

Question 15

Early targeted intervention, educational programs, and support with:

Answer 15

1. Speech therapists to help and improve their communicate skills and use language more
   effectively. 2. Physical therapists includes activities and exercises that help them build motor skills,
   increase muscle strength, and improve posture and balance. 3. Occupational therapists helps find ways to adjust everyday tasks and conditions to match a
   person’s needs and abilities. 4. Emotional behavioral therapists to help manage emotional challenges that can come with
   Down syndrome like autism.