Learning Disabilities Flashcards
What is autism spectrum disorder (ASD)?
A neuro-developmental disorder characterised by abnormal social interaction, communication and restricted, repetitive behaviours
Is ASD more prevalent in boys or girls?
ASD is four times more prevalent in boys than girls.1
Prevalence of ASD in UK?
In the UK, 1 in 100 people are considered to be on the autistic spectrum.
How does Asperger syndrome differ from autism?
Asperger’s is characterised by the absence of intellectual impairment and/or impairment of functional language.
In most cases, there is no identifiable cause for ASD however there are a few known, predisposing medical conditions.
What are they?
- Infantile spasms
- Congenital rubella
- Tuberous sclerosis
- Fragile X syndrome
Give some risk factors for ASD
- Male sex
- Family history
- Genetic variants such as PTEN, MeCP and several submicroscopic copy number variants (CNV)
- Chromosomal abnormalities
Previous diagnoses such as Asperger’s and autistic disorder have now been grouped into one spectrum disorder. What is this spectrum?
Suggests that the same disorder was responsible for the features of the condition and those affected fall somewhere along the spectrum.
What 3 categories can typical features of ASD be grouped into?
- Social interaction
- Communication
- Restricted, repetitive behaviours
What ‘social interaction’ features can be seen in ASD?
Lack of eye contact
Delay in smiling
Avoids physical contact
Unable to read non-verbal (social) cues
Difficulty establishing friendships
Not displaying a desire to share attention (i.e. not playing with others)
What ‘communication’ features can be seen in ASD?
Usually delayed or minimal expressive speech
Impairment in make-believe or fantasy play
Lack of social gestures
Conversational skills tend to be one-way (monologues, endless questions etc…)
Lack of appropriate non-verbal communication such as smiling, eye contact, responding to others and sharing interest
Repetitive use of words or phrases
What ‘behaviour’ features can be seen in ASD?
Greater interest in objects, numbers or patterns than people
Stereotypical repetitive movements. There may be self-stimulating movements that are used to comfort themselves, such as hand-flapping or rocking.
Intensive and deep interests that are persistent and rigid
Repetitive behaviour and fixed routines
Anxiety and distress with experiences outside their normal routine
Extremely restricted food preferences
What conditions have increased prevalence in people with ASD?
- ADHD (around 50%)
- Epilepsy (20-30%)
- Bowel disorders (10-15%)
- Schizophrenia
- Sleep disorders
- Down syndrome
Give 2 differentials for ASD
- Global developmental delay
- ADHD
What is the difference between global developmental delay and ASD?
Global developmental delay –> delay occurring in all areas of development, not just social/communication
How is a diagnosis of ASD made?
A diagnosis of ASD is based on clinical assessment with deficits occurring across all three aforementioned domains.
These features must be observable in all environments that are sufficient to cause impairment in functional capacity.
They should have been present from early childhood but may not be fully evident until later when social demands exceed capabilities.
Management of ASD?
No cure but the goal of treatment is to improve day-to-day functional ability and optimise the quality of life.
Non-pharmological:
- Specialist education
- Occupational therapy
- Speech therapy
- Clinical psychology
- Sleep hygiene
- Care agencies
Pharmacological:
- There are no specific medications for ASD; however, patients with symptoms of depression and/or anxiety may benefit from behavioural and pharmacological intervention (e.g. SSRIs).
- In addition, children with sleep difficulties which may benefit from a trial of melatonin if behavioural management/sleep hygiene proved to be unsuccessful.
Tips for communicating with ASD patients:
- Try not to have too many people in the room
- Try to find out in advance how the patient communicates e.g. [pictures/symbols (can ask carer/parent to bring)
- Use clear, direct literal language without any turns of phrase or sarcasm that may be misconstrued.
- Having a highly structured clear routine i.e. now it’s breakfast, next you will see the doctor.
- Enabling company of people they trust is vital to help reduce stress and calm behaviours.
What are some complications of ASD?
Social isolation
Bullying and victimisation
Problems in education
Problems with employment
Inability to live independently
What are the 3 criteria for a learning disability?
1) An IQ <70
2) Loss of adaptive social functioning
3) Onset before age of 18
What IQ range defines a MILD learning difficulty
50-69
Likely to result in some learning issues at school. Manyadults will be able to work and maintain relationship
What IQ range defines a MODERATE learning difficulty
35-49
Likely to result in some learning issues at school. Manyadults will be able to work and maintain relationship
What IQ range defines a SEVERE learning difficulty?
20-34
Likely to result in continuous need of support
What IQ range defines a PROFOUND learning difficulty?
<20
Severe limitations in self-care, continence,communication and mobility
What is the most common cause of learning disability?
Down’s syndrome (approx 1/1000 births)
How does maternal age affect risk of Down’s syndrome?
Incidence rises with advanced maternal age
(1 in 1400 at 25yrs, 1 in 30 at 45yrs)
What is the most common chromosomal abnormality implicated in Down’s syndrome?
Trisomy 21 (95%)
There is an extra copy of chromosome 21, leading to a total of three instead of the typical two.
Give 2 other chromosomal abnormalities implicated in Down’s syndrome
- Robertsonian translocation (4%)
- Mosaicism (1%)
GIve some physical characteristics of Down’s syndrome
Short stature
Rounded skull
Slope of palpebral fissures
Epicanthic fold
Single palmar crease
Hypotonia (decreased muscle tone)
What is the genetic mechanism responsible for Down’s Syndrome (Trisomy 21)?
Gamete non-disjunction
In nondisjunction, the separation fails to occur causing both sister chromatids or homologous chromosomes to be pulled to one pole of the cell.
What are the 3 main genetic mechanisms resposible for Down’s Syndrome?
- Gamete non-disjunction: Accounts for ~95% of cases; the incidence increases with maternal age.
- Robertsonian translocation: Sometimes referred to as familial Down syndrome or translocation Down syndrome; accounts for ~4% of cases.
- Mosaic Down syndrome: The least common form, accounting for ~1% of cases; this often leads to variable expression of the Down syndrome phenotype.
What are the characteristic facial features in Down’s Syndrome?
Upward-slanting palpebral fissures
Epicanthal folds
Protruding tongue
Small low-set ears with adherent earlobes
Hypoplastic nasal bridge - broad and flat
Small oral cavity
A SINGLE transverse palmar crease.
Give some other clinical features of Down’s Syndrome other than facial features
Short stature
Learning difficulties
Congenital heart defects (including ventricular septal defect)
When are pregnant women offered a screening test for Down’s Syndrome?
Under the current NHS screening programme, all pregnant women are offered a screening test between 10 and 14 weeks to assess the chances of having a baby with trisomy 13, 18, and 21. Further genetic testing may confirm the diagnosis.
Potential complications of Down’s Syndrome?
Risk of:
- Abnormalities of internal organs e.g. ASD, VSD, oesophageal atresia
– Cataracts
– Hypothyroidism
– Chest infection
– Transient leukaemia
– Epilepsy
– Alzheimer’s Dementia
Management of Down’s Syndrome?
Management of Down syndrome involves a multidisciplinary approach due to the multiple system involvement.
E.g. A combination of medical interventions, therapies, and support systems to address physical, developmental, and social needs. Regular health check-ups and early intervention programs are key aspects of managing Down syndrome.
What is of Foetal Alcohol Syndrome (FAS)?
Prenatal alcohol exposure leading to various neurological, facial, and growth abnormalities
How is a diagnosis of FAS established?
The diagnosis of FAS primarily relies on clinical criteria, including history of prenatal alcohol exposure (when available), assessment of physical anomalies, and evidence of central nervous system abnormalities.
What is the only certain method to prevent FAS?
Abstinence from alcohol during pregnancy
How does FAS differ from Foetal Alcohol Spectrum Disorder (FASD)?
FASD is an umbrella term for several conditions related to prenatal alcohol exposure
What is the leading preventable non-genetic cause of LD?
FASD
What % of people with FAS have a learning disability?
25-30%
What are the 3 key features of FAS?
1) Growth retardation
2) Characteristic facial features
3) CNS dysfunction e.g. affect dysregulation and inattention
What is the extent of harm in FAS influenced by?
- The amount and frequency of alcohol consumption
- The stage of pregnancy during exposure
- Genetic susceptibility of the foetus
- Maternal health and nutritional status
What are the manifestations of growth impairment in FAS?
Low birth weight
Decelerating weight over time
What are the characteristic facial features in FAS?
Low nasal bridge
Thin upper lip
Flat midface and short nose
Short palpebral fissures
Epicanthal folds
Indistinct/smooth philtrum
Micrognathia
What CNS abnormalities can be seen in FAS?
Decreased cranial size, structural brain abnormalities, problems with attention, cognitive difficulties.
Give 3 differentials for FAS
1) Genetic syndromes e.g. Down’s syndrome, Williams syndrome (cognitive difficulties and facial abnormalities but lack of prenatal alcohol exposure)
2) Prematurity (low birth weight and developmental issues but no facial features)
3) Neglect and malnutrition (growth delays but no facial and brain abnormalities)
Management for FAS?
No cure, only symptomatic treatment and supportive care
Special education programs to manage cognitive difficulties.
Speech and occupational therapy to address developmental delays.
Medical management for comorbid conditions like attention deficit hyperactivity disorder (ADHD) or seizures.
Social services support for affected families.
What is the most common inherited cause of LD?
Fragile X syndrome (FXS)
What genetic mutation is seen in Fragile X syndrome?
An expansion of the CGG trinucleotide repeat in the FMR1 gene on the X chromosome
What gene is implicated in FXS?
FMR1 gene located on the X chromosome
Do males or females tend to have more severe symptoms in Fragile X? Why?
males tend to have more severe symptoms due to the X-linked nature of the condition.
Males, having only one X chromosome (XY), will develop FXS because there is a mutation of their single X chromosome. Females, who have two X chromosomes (XX), can have the unaffected X reduce the effects of the affected X. This typically leads to no or milder symptoms of FXS.
What signs and symptoms are seen in FXS?
- Long, narrow face
- Large, protruding ears
- Intellectual impairment (mild to profound)
- Post-pubertal macroorchidism (large testes)
- Social anxiety
- Autistic spectrum features
- Delayed motor milestones
- Speech and language delay
- Prominent jaw & forehead
- Mitral valve prolapse
Definitive investigation for FXS?
The definitive investigation for Fragile X Syndrome is a genetic test that detects the number of CGG repeats in the FMR1 gene
Can also identify carriers
How are mental illness and learning disability interlinked?
Higher incidence and prevalence of mentalillness in people with LD:
- More likely to experience biological and psychosocial risk factors
- People with LD may have fewer internal resources to cope with mental and social stressors (e.g. coping style, self esteem, resilience)
- Social vulnerability (e.g. small circle of friends, reduced employment opportunities etc)
What problems with diagnosis can be seen in those with learning disabilities?
- Communication can be difficulty
- Changes in behaviour can be important diagnostic sign
People with learning disabilities may present differently with depression.
Biological symptoms are often more prominent.
Give some examples:
– Agitation
– Appetite
– Weight
– Sleep
– Self care / Regression
– Psychomotor retardation
– Tearfulness
What may depressive features in people with LD also indicate the onset of?
Dementia
How do antidepressants differ in those with LD?
Response to antidepressant medication may take LONGER or there may be increased SENSITIVITY to side-effects.
How are dementia and Down’s syndrome interlinked?
Dementia is more common in people with Down’s Syndrome
When does dementia typically appear in those with LD?
It often occurs earlier
Be aware of changes in behaviour as an early indicator of dementia
How are anxiety and LD interlinked?
May be increased risk of anxiety in those with LD due to:
- Lack of confidence in everyday situations
- Those with autism may find it difficult to cope with the unpredictability of everyday life
Management options for anxiety in those with LD?
Treatment options same as general population
In any suspected mental illness/change in behaviour in those with LD, what should you be aware of?
Physical causes
What condition is ASD most commonly associated with?
ADHD (50%)
What is adaptive social functioning?
Adaptive functioning refers to a person’s ability to effectively manage daily living tasks and social interactions as compared to their age, cultural, and environmental expectations.
For example, suppose a child can dress appropriately for the weather and age-appropriately interact with peers
What is an epicanthic fold?
An epicanthal fold is a skin fold of the upper eyelid covering the inner corner of the eye.
What are palpebral fissures?
The palpebral fissure is the area between the open eyelids.
Sloping palpebral fissures can be seen in Down’s syndrome.
What is trisomy 18?
Edwards syndrome
What is trisomy 13?
Patau syndrome
What is Patau syndrome? Chance of survival?
A chromosomal condition associated with severe intellectual disability and physical abnormalities in many parts of the body.
Individuals with trisomy 13 often have heart defects, brain or spinal cord abnormalities, very small or poorly developed eyes (microphthalmia), extra fingers or toes, an opening in the lip (a cleft lip) with or without an opening in the roof of the mouth (a cleft palate), and weak muscle tone (hypotonia).
Due to the presence of several life-threatening medical problems, many infants with trisomy 13 die within their first days or weeks of life. Only five percent to 10 percent of children with this condition live past their first year.
What is Edward’s syndrome? Chance of survival?
Individuals with trisomy 18 often have slow growth before birth (intrauterine growth retardation) and a low birth weight. Affected individuals may have heart defects and abnormalities of other organs that develop before birth. Other features of trisomy 18 include a small, abnormally shaped head; a small jaw and mouth; and clenched fists with overlapping fingers.
Due to the presence of several life-threatening medical problems, many individuals with trisomy 18 die before birth or within their first month. Five to 10 percent of children with this condition live past their first year, and these children often have severe intellectual disability.
What chromosomal abnormalities are routinely screened for in pregnancy?
Trisomy 13 –> Patau syndrome
Trisomy 18 –> Edward’s syndrome
Trisomy 21 –> Down’s syndrome
