Down Syndrome Flashcards
What is another name for Down syndrome?
Trisomy 21
What is the most common congenital chromosomal abnormality?
Down syndrome
What causes the phenotypic features of Down syndrome?
Additional genetic material from chromosome 21 (three copies)
What percentage of Down syndrome cases are due to meiotic non-disjunction of maternal chromosome 21?
95%
What is the main risk factors for Down syndrome?
Increasing maternal age (esp. > 40 years)
List some general dysmorphic features of Down syndrome.
- hypotonia
- hyperflexibility
What are some head dysmorphic features associated with Down syndrome?
- upward sloping palpebral fissures
- prominent epicanthic folds
- flat nasal bridge
- brachycephaly
- short neck
- dysplastic, low-set, small ears
What hand feature is commonly seen in individuals with Down syndrome?
Single palmar crease (Simian crease)
What is the ‘sandal toe deformity’ in Down syndrome?
Large gap between first and second toes
Name two neurological complications associated with Down syndrome.
- Developmental delay & learning disabilities
- Alzheimer’s disease
What type of congenital cardiac defects are common in Down syndrome?
- AVSD
- ASD
- VSD
- patent ductus arteriosus
- tetralogy of Fallot
What are two endocrine complications associated with Down syndrome?
- hypothyroidism
- type 1 diabetes
List three gastrointestinal complications associated with Down syndrome.
- duodenal atresia
- tracheo-oesophageal fistula
- Hirschsprung disease
What is the screening test threshold for Down syndrome risk?
Risk of DS > 1 in 150
What is the combined test for Down syndrome screening?
Between 11 & 14 weeks gestation, includes ultrasound and maternal blood tests
What does the quadruple test measure?
- beta-HCG (high)
- AFP (low)
- serum oestriol (low)
- inhibin-A (high)
Completed between 14 & 20 weeks
What is chorionic villus sampling?
Ultrasound guided biopsy of placental tissue
Completed between 9 & 12 weeks
What is amniocentesis?
Ultrasound guided aspiration of amniotic fluid
Completed between 14 & 20 weeks
What does non-invasive perinatal testing (NIPT) measure?
cfDNA in mother’s blood
What type of care is provided for individuals with Down syndrome?
Supportive care from a multi-disciplinary team
List some services included in the management of Down syndrome.
- genetic counselling
- occupational therapy
- speech & language therapy
- paediatrician
- GP
- nursing care
- physiotherapy
- dietician
- cardiologist
- ENT specialists
- audiologists
- opticians
