EXTRAPYRAMIDAL DISORDERS Flashcards

1
Q

Function of the basal ganglia?

A

It’s like a collection of brakes or accelerators

To fine-tune voluntary movements
It recieves impulses fron the cerebral cortex, processes them and adjusts them and then covey this infromation to the thalamus and then back to the cortex
Ultimately the fine-tuned movement instruction is sent to skeletal muscles via the spinal cord

Also involves in planning, modulation of movements, memory, eye movements, reward processing and motivation

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2
Q

Components of the basal ganglia?

A

Caudate nucleus
Putamen
Nucleus accumbens and olfactory tubercle
Globus pallidus
Subthalamic nucleus
Substantia nigra

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3
Q

Which part of the striatum is part of the basal ganglia?

A

The dorsal striatum

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4
Q

What are the 2 components of the striatum?

A

The caudate nucleus and the putamen

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5
Q

What forms the corpus striatum?

A

The striatum and the globus pallidus

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6
Q

Input nuclei of the basal ganglia?

A

The striatum and the caudate nucleus

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7
Q

What is the nucleus accumbens?

A

The most cranial aspect of the striatum where the caudate nucleus and the putamen join together

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8
Q

Function of striatum?

A

It recieve excitatory glutamatergic inputs from the cerebral cortex.
The synapsing pattern reflects topography of the cortex e.g. caudal parts of the cortex project to the caudal part of the brain the striatum

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9
Q

Structure of the caudate nucleus?

A

Consists of a head, tail and the body
Terminates by connecting with the amygdala at the tail of the caudate nucleus

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10
Q

Function of the caudate nucleus?

A

Integrates sensory information about the spatial position of the body and according to that sends infromation about necessary fine tunes of motor response to that stimuli to the thalamus
Also contributes to body & limb posture and speed &accurary of directed movements

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11
Q

Intrinsic nuclei of the basal ganglia?

A

External globus pallidus
Subthalamic nuclei
Pars compacta of the substantia nigra

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12
Q

Output nuclei of the basal ganglia?

A

Internal globus pallidus
Pars reticulata of the substantia nigra

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13
Q

Function of putamen?

A

To regulate motor functions and influence various types of learning
It uses dopamine

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14
Q

What are the 2 divisions of the globus pallidus?

A

The internal globus pallidus and the external globus pallidus

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15
Q

What are the 2 components of the substantia nigra?

A

The pars compacta and the pars reticulata

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16
Q

Function of the substantia nigra pars compacta?

A

Output to the basal ganglia circuit, supplying the striatum with dopamine through specific D1 and D2 neurones within the nigrostriatal pathways

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17
Q

Function of the substantia nigra pars reticulata?

A

Serves as input - conveys signals from the basal ganglia to the thalamus

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18
Q

Why does the substantia nigra have a dark appearance?

A

Due to the neuromelanin present in the cells in the pars compacta

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19
Q

Arterial supply to the basal ganglia?

A

Middle cerebral artery - main aretry is the lenticulostriate artery

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20
Q

Direct pathway of basal ganglia structure

A

Glutamate neurones project from the thalamus to motor regions of cerebral cortex = excitatory = stimulates movement

Neurones from the globus pallidus internal and substantia nigra pars reticulata project to the thalamus and release GABA = inhibition = suppression of movement to prevent unwanted movements from occurring

Infromation from movement is sent from cortex to striatum via the corticostriatal pathway. Glutamate nuyerones excite neurons on the striatum. Activated stiatam neurones release GABA in the globus pallidus internal and substantia nigra pars reticulata = inhibition of these regions = stops inhibition of neurones in the thalamus which are involved in movement = movement can occur!

Neurones from the substantia nigra pars compacta travel to the striatum via the nigrostriatal pathway and release dopamine in the striatum = facilitates activity in direct pathway

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21
Q

Indirect pathway of the basal ganglia structure

A

GABA neurones project from globus pallidus external to the Subthalamic nucleus = inhibition on glutamate neurones in Subthalamic nucleus

Signals from cerebral cortex causes activation of GABA neurones in the striatum which projects to the globus pallidus external and inhibits thr activity of neurones there. This prevents globus pallidus external neurones from inhibiting the neurones in the Subthalamic nucleus

Projections from the cortex activate the Subthalamic nucleus neurones and stimulate GABA neurones in the globus pallidus internal and substantia nigra pars reticulata = project to the thalamus = inhibits thalamic neurones that travel the motor regions of the cerebral cortex to stimulate movement = therefore inhibits movement

This antagonises the activity of the direct pathway and acts to keep unwanted movements from occurring

Neurones from the substantia nigra pars compacta travel to the striatum via the nigrostriatal pathway. These can modulate the activity of the indirect pathway through dopamine release in the striatum = inhibition of activity in indirect pathway = facilitation of movement

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22
Q

What broadly causes movement disrders?

A

Disturbance of the cerebellum and extrapyramidal system e.g. basal ganglia, thalamus, Subthalamic nuclei and red nucleus

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23
Q

Positive symptoms of movement disorders?

A

Chorea
Athetosis
Ballismus
Dystonia
Tremor
Rigidity

(Due to disinhibition of undamaged parts of the motor system)

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24
Q

Negative symptoms of movement disorders?

A

Hypokinesia and bradykinesia

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25
What is a tremor?
An involuntary, regular, rhythmic, oscillatory movement produced by alternating or irregularly synchronous contractions of antagonistic muscles
26
Types of tremor?
Physiological Exaggerated physiological e.g. thyrotoxicosis or anxiety Essential tremor Dystonic tremor Cerebellar tremor Parkinsonian tremor Functional tremor
27
What is an essential tremor?
An autosomal dominant condition that affects both upper limbs usually There is often a strong FHx
28
Features of an essential tremor?
It’s a postural tremor i.e. worse if arms are outstretched Improved by alcohol and rest It’s the most common cause of titubation (a head tremor)
29
Why does alcohol improve an essential tremor?
Alcohol enhances GABA which is inhibitors and dampens the excessive firing of neurones
30
Management of essential tremor?
Propranolol first line
31
What is titubation?
Head tremor
32
Type of tremor seen in parkinsonism?
Resting, pill-rolling tremor
33
Causes of tremor?
Parkinsonism Essential tremor Anxiety Thyrotoxicosis Hepatic encephalopathy CO retention Cerebellar disease Drug withdrawal e.g. alcohol or opiates
34
What type of tremor does cerebellar disease cause/
An intention tremor
35
What is an intention tremor?
Involuntary, thyroid muscle contractions that occur during purposeful, voluntary movement e.g. reaching for something Most commonly affects the upper limbs
36
What is myoclonus?
A brief, involuntary, shock-like contraction of a group of muscles; Irregular in rhythm and amplitude, asynchronous and asyemmetrical Can cause whole body to jerk or just an area Caused by abnormal discharges in the CNS of motor neurones or interneurones
37
What is chorea?
“To dance” Brief, semi-directed, irregular movements that are not repetitive or rhythmic, but appear to flow from one muscle to the next
38
What is hemiballismus?
Unilateral - affects ipsilateral arm & leg Intermittent, sudden involuntary large movements
39
What is athetosis?
Slow, involuntary, convoluted, writhing movements of hands and feet Slow, sinuous movements that flow into 1 another
40
What is dystonia?
Sustained muscle contractions causing abnormal, often repetitive movements or postures Movements are typically twisting, patterned or tremulous It can be focal, segmental or generalised Tremor is often a feature Often worsened by voluntary movements
41
Where is the lesion likely in a patient with athetosis?
In the lentiform nucleus in the basal ganglia
42
Where is the lesion likely in a patient with chorea?
Caudate nucleus
43
Causes of chorea?
Inherited e.g. huntingtons, Wilson’s Sydenhams (as a consequence of rheumatic fever) Hormonal and endocrine - typically oestrogen-related e.g. in pregnancy or SE of contraceptive pill Degenerative Drugs e.g. phenytoin, neuroleptics Structural - stroke, tumours, trauma SLE Polycythemia vera
44
Causes of athetosis?
Birth hypoxia or kernicterus Hepatic encephalopathy All other causes same as chorea: Inherited e.g. huntingtons, Wilson’s Sydenhams (as a consequence of rheumatic fever) Hormonal and endocrine - typically oestrogen-related e.g. in pregnancy or SE of contraceptive pill Degenerative Drugs e.g. phenytoin, neuroleptics Structural - stroke, tumours, trauma SLE Polycythemia vera
45
Where is the lesion likely to be in a patient who has hemiballismus?
Subthalamic nuclei
46
What is considered the commonest form of tremor?
Dystonic tremor
47
Causes of dystonia?
Genetics Drug-induced e.g. parkinsonian medications and neuroleptics Related to trauma Idiopathic
48
What is parkinsonism?
An umbrella term for the clinical syndrome involving bradykinesia plus at least one of tremor, rigidity or postural instability
49
Causes of parkinsonisms?
Parkinson’s disease Drug induced e.g. antipsychotics and metoclopramide Degenerative: Progressive supranuclear palsy, Multiple system atrophy Metabolic: Wilsons disease Infection: Post-encephalitis, prion disease e.g. cruz-felt Jakob disease Dementia pugilistica Toxins e.g. CO, MPTP, mercury
50
What is dementia pugilistica?
A form of chronic traumatic encephalopathy Caused by chronic head trauma Commonly seen in boxing
51
Red flags to diagnosing parkinsonsism and a cause that is not parkinsons disease?
Recent use of dopamine blocking drugs Lack of the typical tremor (resting pill-rolling) Symmetrical signs (parkinsons is usually asymmetrical i.e. affects 1 side more than the other) Early cognitive dysfunction Early balance disturbances eg. In PSNP where people tend to fall backwards Significant and early autonomic dysfunction e.g. MSA Poor response to usual parkinsons medications
52
Dementia with Parkinson’s vs dementia with Lewy body?
The only real difference is that in Lewy body dementia, the dementia occurs first before the motor symptoms (may also have recurrent visual hallucinations & act out dreams) In parkinsons, the motor symptoms occur first and then dementia follows
53
What is parkinsons disease?
A chronic, progressive neurodegenerative condition resulting from the loss of the dopamine-containing cells of the substantia nigra The dopamine deficiency within the basal ganglia leads to a movement disorder with classical parkinsonian motor symptoms
54
How much dopaminergic cell activity must be lost for parkinsons disease to be clinically apparent?
At least 50%
55
Cause of parkinsons?
Dopamine denervation due to Lewy body deposition and cell death in the substantia nigra A large number of extra-nigral and non-dopaminergic brain regions are also affected Minority of people have a FHx - associated with early-onset i..e <40
56
Most common cause of parkinsonisms?
Parkinson’s disease
57
Epidemiology of parkinsons disease?
Common Mean age of diagnosis is 65 Increases with age - nearly 2% of over 80s Prevalence higher in men Lifetime risk is 2.7%
58
Complications of parkinsons disease?
Motor complications e.g. deteriorating function, dyskinesia, falls, NMS Mental health problems Autonomic dysfunction e.g. orthostatic hypotension, syncope, excessive salivation, sweating, bladder and bowel problems, sexual problems Sleep disturbances
59
Symptomatic progression of parkinsons disease?
In early disease the motor symptoms are usually unilateral It’s progressive so by later disease its usually bilateral
60
Symptoms of Parkinson’s disease?
Resting tremor Gradual onset progressive bradykinesia Rigidity Others: Postural instability Gait disorders - shuffling, festination or freezing Mental health problems - usually depression + insomnia + Cognitive impairment Anosmia Hypomima - reduced facial expression Sleep disturbance Fatigue Autonomic dysfunction e.g. postural hypotension, hyperhidrosis Dysphagia Drooling Blurred vision and eye opening ataxia Constipation & urinary incontinence
61
Describe the bradykinesia seen in parkinsons disease?
Slowness in initiation of voluntary movement with progressive reduction in speed and amplitude of sustained repetitive actions e.g. finger tapping Poverty of movement can also be seen - sometimes referred to as hypokinesia
62
How can hypokinesia present in parkinsons disease?
Reduced or flat facial expression Reduced blinking Difficulty with fine movements e.g. handwriting, buttoning clothes Slow, short shuffling gait with reduced arm swinging Freezing gait
63
Type of rigidity seen in parkinsons disease?
Lead-pipe rigidity or cogwheel rigidity
64
What is lead-pipe rigidity?
Constant resistance felt when a limb is passively flexed in the presence of increased tone without tremor
65
What is cogwheel rigidity?
Cogwheel rigidity refers to resistance that stops and starts as the limb is moved through its range of motion. Like going through the cogs!! This is with a tremor
66
When does the resting tremor in Parkinson’s disease typically improve?
On moving, with mental concentration and during sleep
67
What is a pill-rolling tremor?
Simultaneous rubbing movements of the thumb and index fingers against each other e.g. appears they are rolling a small object between their fingers
68
Drug causes of parkinsonisms?
Antipsychotics - usually first-generation e.g. haloperidol Anti-emetics e.g. prochlorperazine and metoclopramide More rarely: Antidepressants e.g. SSRIs CCB Cinnarizine Amiodarone Lithium Cholinesterase inhibitors e.g. donepezil Sodium valproate Methyldopa Pethidine
69
What typically worsens the resting tremor seen in parkinsons?
Stress or being tired
70
How can drug-induced Parkinsonism present differently to parkinsons disease?
Motor symptoms have a rapid onset and are bilateral Rigidity and resting tremor are uncommon
71
What can you do if you have difficulty differentiating between an essential tremor and Parkinson’s disease?
123I‑FP‑CIT single photon emission computed tomography (SPECT). A type of functional Neuroimaging that can assess dopamine levels
72
What are the 2 types of multiple system atrophy?
MSA-P - predominant parkinsonian features MSA-C - predominant cerebellar features
73
Features of multiple system atrophy?
parkinsonism autonomic disturbance - erectile dysfunction, postural hypotension and atonic bladder, urinary retention cerebellar signs - ataxia
74
What is multiple system atrophy?
A rare, neurodegenrative disorder characterised by autonomic dysfunction, Parkinsonisms and ataxia Usually affects ~55 Its caused by progressive degeneration of neurones in the basal ganglia, inferior oligarch nucleus and cerebellum
75
What is progressive supranuclear palsy?
Aka Steele-Richardson-olszewski syndrome It’s a ‘Parkinson Plus’ syndrome A late-onset (~63) neurodegenerative disease involving gradual deterioration and death of specific volumes of the brain Involves accumulation of tau protein in the brain
76
Features of progressive supranuclear palsy?
Postural instability and falls - tend to have a stiff, broad-based gait. Particularly falls backwards Impairment of vertical gaze e..g difficulty reading or ascending stairs Parkinsonism with bradykinesia being prominent - symmetrical Cognitive impairment - mostly frontal love dysfunction
77
pathophysiology of drug-induced parkinsonism
Medications which reduce dopamine levels from the basal ganglia = brain cannot transmit signals to correctly coordinate movement
78
Advice about driving for patients with parkinsons?
DVLA days that group 1 and 2 may drive as long as safe vehicle control is maintained at all times
79
First line medical treatment for parkinsons disease if motor symptoms are affecting the patient’s quality of life?
Levodopa
80
First line medical treatment for parkinsons if motor symptoms are not affecting the patient’s quality of life?
Oral MAO-B inhibitors OR levodopa OR oral/transdermal dopamine agonists
81
Examples of oral MAO-B inhibitors?
Selegiline, rasagiline or safinamide
82
Examples of oral dopamine agonists that can be used for parkinsons disease?
Pramipexole or ropinirole
83
Example of transdermal dopamine agonist that can be used for parkinsons?
Rotigotine
84
Levodopa vs MAO-B inhibitors vs dopamine agonists for Tx of parkinsons?
Levodopa typically provides more improvement in motor symptoms and daily functioning, fewer adverse effects but may cause more motor complications Oral MAO-B usually provide less improvement in motor symptoms and daily functioning, fewer motor complications and fewer adverse effects Dopamine agonists provide less improvement in motor symptoms and daily functioning, fewer motor complications but more adverse effects e.g. excessive sleepiness, hallucinations and impulse control disorders
85
Specific adverse efefcts of dopamine agonists for parkinsons disease?
Excessive sleepiness Hallucinations Impulse control disorders
86
What are impulse control disorders?
A group of behaviour disorders characterised by impulsivity E.g. failure to resist an urge or temptation or having an inability to not speak on a thought E.,g. Gambling or hypersexuality
87
What can be used to manage parkinsons when pt have developed dyskinesia or motor fluctuations despite optimal levodopa therapy?
Additional of a dopamine agonist, MAO-B inhibitor or a COMT inhibitor as an adjunct
88
What are COMT inhibitors and give 2 examples?
Oral Catechol-O-methyl transferase inhibitors Entacapone or opicapone
89
Who are impulse control disorders most common in?
Can occur with any dopaminergic therapy More common with: Dopamine agonist therapy - this doubles the risk! History of previous impulse behaviours History of alcohol consumption or smoking
90
How can we medically manage drooling of saliva in Parkinson’s disease?
Glycopyrronium bromide
91
Non motor sympotms of parkinsons?
Constipation N&V Pain Sleep disturbance and daytime sleepiness Depression and anxiety Dementia and cognitive impairment Impulse control disorders and psychotic symptoms Orthostatic hypotension Speech and swallowing problems & weight loss Excessive salivation and sweating Bladder and sexual problems
92
How is levodopa given for management of parkinsons motor symptoms?
Nearly always given combined with a decarboxylase inhibitor e.g. carbidopa This prevents the peripheral metabolism of levodopa to dopamine outside of the brain as decarboxylase is the enzyme for this = reduces the SE
93
Common adverse efefcts of levodopa
Major: with years of use there is motor fluctuation and dyskinesias Dry mouth Anorexia Palpitations Postural hypotension Psychosis End of dose wearing off : symptoms worsen towards end of dosage interval On-off phenomenon: large variations in motor performance Dyskinesias at peak dose
94
What are dyskinesias?
Involuntary, erratic movement disorders e.g. dystonia, chorea, athetosis
95
What is important information to give patients about stopping levodopa?
It’s important not to acutely stop levodopa as this can cause acute dystonia
96
How do MAO-B inhibitors work to manage Parkinson’s?
They inhibit the breakdown of dopamine secreted by dopaminergic neurons in the substantia nigra
97
Moa of COMT inhibitors for parkinsons?
COMT is an enzyme involved in the breakdown of dopamine so it can be used as an adjunct to levodopa to improve dopaminergic activity in the substantia nigra
98
Why do we often delay treatment for parkinsons?
Treatment does not alter the natural history of parkinsons It avoids the complications of drugs We can introduce the drugs according to the patient’s biological age and functional requirements
99
Why is there an argument for not using Anticholinergics for managing parkinsons?
They possibly cause cognitive slowing and confusion They can cause bladder and bowel dysfunction They must be used with care, especially in the elderly!
100
Why do you have to be cautious about using MAO-B inhibitors in patients with postural hypotension?
As it can increase the risk of cardiac arrhythmias and death
101
2 classes of dopamine agonists?
Ergot based and non-ergot based
102
What can ergot-based dopamine agonists cause as complications?
Impulse disorders Organ fibrosis e.g. retroperitoneal and lung fibrosis
103
What is the duodopa gel?
A combination of levodopa and carbidopa that is administered as a continous infusion via percutaneous jejunostomy tube Very expensive!
104
How can we manage the wearing off symtpms, and peak/end of dose dyskinesia and dystonia caused by levodopa therapy?
Smaller doses more often Use in conjunction with other classes of medication to limit total amoutn of levodopa
105
Main side efefcts of COMT inhibitors?
Severe diarrhoea especially with entacapone Can worsen dyskinesia
106
What is hedonistic homeostatic dysregulation?
Neuropsychological behaviour disorder associated with substance misuse and addiction
107
How common is cognitive impairment in parkinsons disease?
At least 50% of sufferers have some cognitive impairment within5. Years
108
Management of cognitive impairment in parkinsons?
Atypical antipsychotics (note you can’t use typical antipsychotics as they are dopamine blocking so worsen motor symptoms) Cholinesterase inhibitors Memantine if cardiac arrhythmia or mod-sev dementia
109
Why can parkinsons disease cause hypersalivation and drool?
As there can be reduced automatic actions e,g. Swallowing This creates an inability to manage the flow of saliva
110
Sleep disorders common in parkinsons?
Fragmented sleep Vivid & disturbing dreams REM sleep behaviour disorder Restless limbs and akathisia Daytime hypersomnolence Obstructive sleep apnoea Pains nd bladder dysfunction as well as problematic parkinsons Sx can keep pt up
111
Red flags suggesting its not parkinsons?
Early balance problems Symmetrical signs Opthalmoparesis Associated pyramidal and cerebellar signs Absence of resting tremor Early onset of dementia Profound autonomic dysfunction Rapid disease progression Poor response to levodopa
112
What is a DaTSCAN?
A brain scan to diagnose parkinsons disease and differentiate parkinsons syndromes with other diseasese e.g. dementia
113
surgical options for management parkinsons
Thalamotomy - surgical destruction of thalamus. Best for drug-resistant tremor Pallidotomy - surgical destruction of the globus pallidus Deep brain stimulation Cell transplants
114
What is deep brain stimulation?
A surgical procedure that implants a neurostimulator and electrodes which send electrical impulses to specified targets in the brain responsible for movement control Can help with parkinsons, essential tremor, dystonia and some neuropsychiatric conditions too
115
What is cell transplant for parkinsons disease?
The transplantation product is generated from embryonic stem cells and functions to replace the dopamine nerve cells which are lost in the parkinsonian brain A new treatment that is still under research process
116
MDT for parkinsons disease?
Specialist nurses PT OT Speech therapy Support groups Dieticians Social services Continence advisors Psychiatric
117
What is Braak’s hypothesis?
That sporadic parkinsons disease is caused by a pathogen that enters the body via the nasal cavity and subsequently is swallowed and reaches the gut, initiating lewy pathological in the nose and digestive tract
118
2 enzymes involved in breaking down dopamine?
MAO COMT
119
What is Parkinson’s UK?
A charity that funds research to find a cure and help ensure everyone understands the real impact of parkinsons
120
What is Parkinson’s Europe?
A charity that works with and campaign with people with parkinsons They advocate, raise awareness and work with other global parkinsons organisations to provide current info, share good practices and highlight research
121
What is Huntington’s disease?
An autosomal dominant genetic condition that causes progressive neurological dysfunction It’s progressive and incurable.
122
Prognosis of Huntington’s disease?
Typically results in death 20 years after initial symptoms develop
123
Genetics of Huntington’s disease?
Autosomal dominant A trinucletodie repeat disorder: repeat exapansion of CAG (this means anticipation may be seen) Due to a defect in huntingtin gene on chromosome 4 which codes for huntingtin protein
124
What is anticipation?
A feature of trinucletodie repeat disorders where successive generations have more repeats in the gene resulting in earlier age of onset and increased disease severity
125
Pathophysiology of Huntington’s disease?
Genetic mutation results in degeneration of cholinergic and GABAergic neurons in the striatum of the basal ganglia
126
What age does Huntington’s disease occur?
After 35 years of age Usually 30-50
127
Presentation of Huntington’s disease?
Chorea Dystonia Saccadic eye movements Personality changes e.g. irritability, apathy, depression Intellectual impairment Dysphagia
128
Rigidity vs spasticity cause?
Rigidity - extrapyramidal disorders Spasticity - UMN lesion
129
Diagnosis of Huntington’s disease?
Genetic testing
130
Management of Huntington’s disease?
Genetic counselling Physiotherapy to improve mobility, maintain joint function and prevent contractures SALT Tetrabenazine for chorea Manage mental health conditions Advanced directives and end-of-life care
131
What typically causes death in Huntington’s disease?
Aspiration pneumonia (Note suicide is also a common cause)
132
Pathophysiology of parkinsons disease?
Progressive degeneration of dopaminergic neurones within the pars compacta of the substantia nigra in the midbrain for many reasons (not really known) Lewy bodies (eosinophilic intraneuronal inclusions) are found in the surviving neurones Nigral cells projecting to the striatum in the nigrostriatal pathway are mostly affected = loss of dopamine in striatum = movement is not smooth, coordinated or controlled
133
What are Parkinson plus syndromes?
Other forms of parkinsonism that have clinical features that are not typical of parkinsons disease Progressive supranuclear palsy, multi system atrophy and corticobasal degeneration
134
What is corticobasal degeneration?
A rare disorder characterised by strikingly unilateral involvement with rigidity and dystonia in arms. Can also cause an “alien” arm, tremors, ataxia, slow slurred speech, dementia, difficult swallowing Areas of the brain die and shrink
135
Which dopamine receptors are excitatory and which are inhibitory?
Excitatory - D1-class receptors Inhibitory - D2-class receptors
136
Risk factors for parkinsons disease?
FHx Genetics Pesticides
137
Protective factors for parkinsons disease?
Smoking Coffee Vigorous exercise Nicotine Use of NSAIDs Omega 3 fatty acids
138
why shouldn’t parkinsons medications be stopped abruptly?
Can cause dopamine agonist withdrawal syndrome May also cause acute dystonia
139
Symptoms of dopamine agonist withdrawal syndrome?
Anxiety and panic attacks Dysphoria - sense of unease due to a mismatch between biological sex and gender Depression Agitation Irritability Suicidal ideation Fatigue Orthostatic hypotension N&V Diaphoresis Generalised pain Drug cravings