Ataxia Flashcards
What is ataxia?
Loss of order in executing movement
What does the term ataxia refer to? (2)
- Umbrella term for a group of neurological disorders affecting balance, co-ordination and speech
- A sign, not a disease and results from cerebellar dysfunction
Why does ataxia occur? (2)
- Can result from structural damage to the cerebellum
- Can be genetic or acquired
- Can also occur due to damage to spinal cord or other nerves
What is the prevalence of ataxia? (3)
- 10,000 people in the UK
- 500 children with progressive ataxia
- Acquired diseases account for the majority (80%) and genetic ataxias (20%)
When is ataxia most commonly diagnosed?
- At any age but certain types are more common at certain ages
What is the aetiology of ataxia?
- Can be genetic or acquired
2. Damage to the cerebellum but also damage to spinal cord or other nerves
Give 4 ways that ataxia can be inherited
- Autosomal recessive
- Autosomal dominant
- Mitochondrial
- X-linked
Give 5 ways that ataxia can be acquired
- Toxic causes
- Immune mediated
- Neurodegenerative
- Idiopathic sporadic
- Vascular/structural
Give 3 toxic causes of ataxia
Alcohol
Phenytoin
Lithium
Give 5 types of immune-mediated ataxia
- Paraneoplastic cerebellar degeneration
- Post-infectious cerebellitis
- Gluten ataxia (GA)
- Ataxia with anti-glutamic acid decarboxylase (GAD) antibodies
- Primary Autoimmune Cerebellar Ataxia (PACA)
Give 11 causes of acquired ataxia
- Severe head injury
- Bacterial brain infection eg. meningitis, encephalitis
- Viral infection eg. chickenpox, measles
- Stroke, haemorrhage or TIA
- Cerebral palsy
- Multiple sclerosis
- Sustained alcohol misuse
- Underactive thyroid gland
- Vitamin B12/E deficiency
- Toxic chemicals eg. mercury, solvents
- Gluten intolerance
Give 2 examples of autosomal recessive inheritance of ataxia
- Freidreich’s ataxia
2. Ataxia-telangiectasia
Give 2 examples of autosomal dominant ataxia
- Episodic ataxia
2. Some cases of spinocerebellar ataxia
Describe idiopathic sporadic ataxia (2)
- Late onset of undetermined cause (50%)
2. Proportion of patients likely to be immune-mediated
Describe gluten ataxia (2)
- Sensitivity to gluten
2. one of the most common forms of sporadic idiopathic ataxia
Describe episodic ataxia (3)
- Characterised by attacks of ataxic symptoms and no/mild symptoms for rest of the time
- Relatively rare group of conditions
- Inherited in autosomal dominant manner (50% chance of passing to children)
Describe spinocerebellar ataxia (3)
- Group of hereditary ataxia
- Don’t often begin until adulthood
- Caused by mutations in different genes (100 identified) Eg. SCA 6
Describe Freidreich’s ataxia (2)
- Most common form of ataxia affecting 1/50,000
2. Inherited mutation (autosomal recessive) in the frataxin gene leading to reduced frataxin
What is the role of frataxin?
A protein essential for life and cell survival
Give 2 types of neurodegenerative ataxia
- MSA-C (multi-system atrophy - cerebellar variant)
2. PSP (progressive supernuclear palsy)
Describe MSA-C (5)
- Autonomic symptoms
- Bulbar symptoms
- Ataxia
- Respiratory hypoventilation
- Characteristic MRI finding
Describe PSP (3)
- Falls/loss of truncal balance
- Restricted eye movements
- Bulbar symptoms
Describe ataxia-telangiectasia (3)
- Rare type of hereditary ataxia
- Symptoms usually begin in early childhood
- Condition rapidly deteriorates, usually live until 19-25 years (some may live into 50s)
Give 9 symptoms of cerebellar dysfunction
- Slurring of speech, dysarthria
- Swallowing difficulties
- Oscillopsia
- Clumsiness (arms and legs)
- Tremor
- Loss of precision in fine motor skills
- Unsteadiness when walking/worse in dark
- Stumbles and falls
- Cognitive impairments
- Nystagmus
What is oscillopsia?
Jumping of the environment due to rapid jerking movements
Give a summary of the diagnosis process of ataxia (5)
- Patient history
- Brain scans (MRI)
- Family history
- Genetic tests
- Other: blood tests (vitamin levels), EMG, ECG, VFS
What information is collected in the patient history? (7)
- Age of onset
- Course of progression
- Additional symptoms
- Pattern of involvement
- Family history
- Drug/alcohol
- Social history
What will an MRI show? (2)
- Highly cerebellar atrophy and dysfunction
2. Excludes cerebrovascular damage, tumours, hydrocephalus, MS, white matter disease, cerebellar dysgenesis
How is the clinical severity rated in ataxia? (2)
- Mild, moderate, severe
2. Scale for the Assessment and Rating of Ataxia (SARA)
Define mild ataxia
Mobilising independently or with one walking aid
Define moderate ataxia
Mobilising with 2 walking aids or walking frame
Define severe ataxia
Predominantly wheelchair dependent
Summarise the treatment of ataxia (3)
- MDT
- Medication
- Management of additional symptoms
What additional symptoms may require management in ataxia? (5)
- Bladder problems
- Eye problems
- Nerve pain
- Depression
- Muscle cramps, spasms and stiffness
What can be used to help muscle cramps, spasms and stiffness? (2)
- Medication eg. baclofen, tizanidine
2. Botox injections
What can be used to help eye problems?
- Gabapentin to control eye muscles (also controls seizures and nerve pain)
What is the cerebellum? (3)
- “Little brain” which controls the timing and pattern of motor activation during movement
- Contains complete motor ans sensory representation of the whole body
- Receives information from the sensory systems, spinal cord and other parts of the brain to regulate movement
Where is the cerebellum located?
Behind the top part of the brainstem
What actions does the cerebellum control? (5)
- Walking and sitting
- Balance
- Limb co-ordination
- Eye movements
- Speech
What is dysdiadochokinesia?
An impaired ability to perform rapid, alternating movements
