Genetic Conditions Flashcards
How common is Down’s syndrome?
1 in 1000
What is the most common aetiology for DS?
Meiotic non-dysjunction
94%
What other aetiologies of DS are there?
Translocation 5%
Mosaicism 1%
What is Robertsonian translocation?
Translocation from Chr21 to Chr14
What organs are affected in DS? (7)
Heart Eyes Ears Thyroid Pancreas - DM Gut Brain
What are the physical features of DS?
Upslanting palpebral folds
Single palmar crease
Wide sandal gap
What are the cardiac defects in DS? (4)
Endocardial cushion defect 40%
VSD 30%
ASD 10%
ToF 5%
Often congenital
What are the later complications of DS?
Learning difficulties Subfertility Hypothyroidism Alzheimers by 40yrs Atlantoaxial instability
What things do you screen for at birth in DS?
Heart defects DM Coeliac Eyes Ears
What do you screen yearly in DS?
Bladder and bowel function
TFTs
Eyes
Ears
What GI issues may be present in DS?
Duodenal atresia
Hirschsprungs
Why do all DS babies need Che analysis?
Translocation = need parental Chr study
Free trisomy = no need
What is the combined screen?
Nuchal translucency
hCG
PAPP-A
What is the quadruple test?
hCG
Oestriol
AFP
Inhibin-A
What is the risk of having a baby with DS if >40yrs?
1 in 100
What is the risk of having a baby with DS if >44yrs?
1 in 50
What is the triad of features for ASD?
Impairment of social interaction
Impairment of communication
Restrictive, repetitive and stereotyped patterns of behaviour
What is different about Asperger’s?
Tend to have above average intelligence
Understand that they do not fit in
What is the prevalence of ASD?
1%
What health problems are associated with ASD?
Learning difficulties
Seizures - 15%
Vision/hearing impairment
What is the management of ASD?
MDT approach
Speech and language to help with language
Education of parents and school
ASD team if regression of language <3yrs old
When must ASD have presented by?
3yrs
What should you do if a child presents with language regression <3yrs old?
Refer to ASD team
What causes 50% of childhood blindness?
Genetic causes eg. DS, CHARGE association
What are some congenital cause of blindness? (5)
Cataracts Albinism Retinal dystrophy Retinoblastoma Congenital infection eg. CMV, rubella
What are some antenatal causes of blindness? (4)
Retinopathy of prematurity
Hypoxic-ischaemic encephalopathy
Cerebral damage
Optic nerve hypoplasia
What are some postnatal causes of blindness? (3)
Trauma
Infection eg. ophthalmic HSV
JIA -> iritis
What is Isolated Delayed Visual Maturation?
No underlying pathology
Rapid and full development between 3-6m
Associated with motor delay