Down's Syndrome Flashcards
What is Down’s syndrome?
Syndrome caused by 3 copies of chromosome 21
Characteristic dysmorphic features
Clinical features of Down’s syndrome
Hypotonia
Brachycephaly(small head with a flat back)
Short neck
Short stature
Flattened face and nose
Prominentepicanthic folds
Upward slopingpalpable fissures
Single palmar crease
Most common cardiac defects in Down’s syndrome?
AVSD
VSD
Patent ductus arteriosus
Routine follow ups in Down’s syndrome
Regular thyroid checks (2 yearly)
Echocardiogram to diagnose cardiac defects
Regular audiometry for hearing impairment
Regular eye checks
Average life expectancy in Down’s syndrome
60
Complications of Down’s syndrome
Learning disability
Recurrentotitis media
Deafness.Eustachian tubeabnormalities lead to glue ear and conductive hearing loss.
Visual problemssuchmyopia,strabismusandcataracts
Hypothyroidismoccurs in 10 – 20%
Cardiac defectsaffect 1 in 3, particularlyASD,VSD,patent ductus arteriosusandtetralogyofFallot
Atlantoaxial instability
Leukaemiaand dementia more common
Antenatal screening for Down’s syndrome
Combined test
Triple Test
Quadruple test
Outline the combined test for Down’s syndrome
Between 11-14 weeks
Combines results from USS and maternal blood tests
Nuchal translucency
Higher beta-HCG
Lower pregnancy-associated plasma-protein-A (PAPPA)
Outline the triple test for Down’s syndrome
Between 14-20 weeks
Maternal blood test results
Higher beta-HCG
Lower alpha-fetoprotein
Lower serum oestriol
Outline the quadruple test for Down’s syndrome
Between 14-20 weeks
Maternal blood test results
Higher beta-HCG
Lower alpha-fetoprotein
Lower serum oestriol
Higher inhibin-A
Antenatal testing for Down’s syndrome
If screening shows risk score >1 in 150, woman offered amniocentesis or chorionic villus sampling
