Down Syndrome Flashcards
What is the pathophysiology of Down Syndrome?
Trisomy 21
What are the three genetic mechanisms responsible for trisomy 21?
Gamete non-disjunction
Robertsonian translocation
Mosaic
What is the most common genetic mechanism responsible for trisomy 21?
Gamete non-disjunction
What are the features of Downs syndrome?
Hypotonia
Brachycephaly (small head with a flat back)
Short neck
Short stature
Flattened face and nose
Prominent epicanthic folds
What are the complications of Downs syndrome?
Learning disability
Recurrent otitis media
Deafness
Visual problems
Cardiac problems
Hypothyroidism
Leukaemia
Alzheimer’s
What kinds of cardiac problems are common in patients with Downs?
ASD
VSD
Tetraology of fallot
Patient ductus arteriosus
Who is offered Downs syndrome screening in pregnancy?
Every woman
What is the first line test for Downs syndrome?
Combined test
When is testing for Downs syndrome carried out?
During 11 and 14 weeks gestation
What is involved in combined testing for Downs?
Ultrasound scan and maternal blood tests
What does ultrasound look for when screening for Downs Syndrome?
Nuchal translucency - the thickness of the back of the neck
What maternal blood test results could suggest Downs syndrome?
High beta-HCG
Low PAPPA
When would further testing be performed for Downs syndrome?
When the calculated risk of Downs is greater than 1 in 150
What further tests are performed?
Amniocentesis or chorionic villus sampling
What is involved in the management of Downs?
MDT approach
Regular check ups:
- Thyroid checks
- Echocardiogram for heart defects
- Audiometry
- Eye checks
