Revision - Parkinson's, Tremor, MS & MND Flashcards
What triad of features is seen in PD?
1) Tremor
2) Bradykinesia
3) Rigidity
Are the symptoms of PD characteristically symmetrical or asymmetrical?
Asymmetrical
Is PD more common in men or women?
2x more common in men
What is the frequency of the tremor in PD?
3-5 Hz
When is the tremor in PD most marked?
At rest
When does the tremor in PD improve?
With voluntary movement
Frequency of benign essential tremor?
6-12 Hz
If there is difficulty differentiating between essential tremor and PD, what investigation can be considered?
I‑FP‑CIT single photon emission computed tomography (SPECT).
What type of dementia can be associated with features of Parkinsonism?
Dementia with lewy bodies
What are the 4 groups of treatment in PD?
1) Levodopa
2) COMT inhibitors
3) Dopamine agonists
4) Monoamine oxidase-B inhibitors
What is levodopa?
Synthetic dopamine
What is levodopa usually combined with?
A peripheral decarboxylase inhibitor (e.g., carbidopa and benserazide)
Stops levodopa from being metabolised before reaching the brain
1st line treatment option in PD if the motor symptoms are affecting the patient’s quality of life?
Levodopa
1st line treatment in PD if the motor symptoms are not affecting the patient’s quality of life?
Dopamine agonist, levodopa or monoamine oxidase B (MAO‑B) inhibitor
What are 2 combination drugs given in PD? (i.e. levodopa + peripheral decarboxylase inhibitor)?
1) Levodopa + carbidopa –> Co-careldopa
2) Levodopa + benserazide –> Co-beneldopa
What is the main side effect of levodopa?
Dyskinesia (abnormal movements associated with excessive motor activity)
Give 3 examples of dyskinesia that may be seen in levodopa use
1) Chorea –> abnormal involuntary movements that can be jerking and random
2) Athetosis –> involuntary twisting or writhing movements
3) Dystonia –> excessive muscle contraction leads to abnormal postures or exaggerated movements
What may be given to manage dyskinesia associated with levodopa?
Amantadine (a glutamate antagonist)
What are COMT inhibitors?
inhibitors of catechol-o-methyltransferase (COMT).
Give an example of a COMT inhibitor used in PD
entacapone
What is the role of the COMT enzyme?
Metabolises dopamine in the body and brain
Purpose of giving COMT inhibitor (e.g. entacapone) in PD?
Entacapone is taken with levodopa (and a decarboxylase inhibitor) to slow the breakdown of the levodopa in the brain. It extends the effective duration of the levodopa.
Give 3 examples of dopamine agonists used in PD
1) bromocriptine
2) cabergoline
3) pergolide
When are dopamine agonists typically used in PD?
They are typically used to delay the use of levodopa, then used in combination with levodopa to reduce the required dose.
What is a notable side effect of prolonged use of dopamine agonists?
Pulmonary fibrosis
Role of monoamine oxidase enzymes?
Break down circulating neurotransmitters such as dopamine, serotonin and adrenaline.
Which monoamine oxidase enzyme is most specific to dopamine?
Monoamine oxidase-B enzyme
Give 2 examples of Monoamine oxidase-B inhibitors used in PD?
1) Selegiline
2) Rasagiline
PD medication can be associated with impulse control disorders.
These can occur with any dopaminergic therapy but are more common which which class of drug?
Dopamine agonists
What are 2 risk factors for a patient developing an impulse control disorder on PD medication?
1) a history of previous impulsive behaviours
2) a history of alcohol consumption and/or smoking
Common side effects of levodopa?
dry mouth
anorexia
palpitations
postural hypotension
psychosis
Some adverse effects are due to the difficulty in achieving a steady dose of levodopa.
Give some examples:
1) End of dose wearing off
2) ‘On-off’ phenomenon
3) Dyskinesias at peak dose
What is the end-of-dose wearing off seen in levodopa use?
Symptoms often worsen towards the end of dosage interval, which results in a decline of motor activity
What is the ‘on off’ phenomenon seen in levodopa use?
Large variations in motor performance, with normal function during the ‘on’ period, and weakness and restricted mobility during the ‘off’ period
If patients with PD taking levodopa are admitted to hospital and cannot take oral meds, what should you do?
Prescribe dopamine agonist patch to prevent acute dystonia
What class of drug is used to treat drug-induced parkinsonism?
Anticholinergics e.g. procyclidine
What are 2 medications that may be used in benign essential tremor?
1) Propanolol
2) Primidone (a barbiturate anti-epileptic medication)
What are the 3 subtypes of MS?
1) relapsing remitting (most common)
2) 1ary progressive
3) 2ary progressive
What is 2ary progressive MS?
Relapsing-remitting that has DETERIORATED and have developed neurological signs and symptoms between relapses.
What is 1ary progressive MS?
progressive deterioration from onset
more common in older people
4 features of optic neuritis?
1) impaired colour vision (red desaturation)
2) central scotoma (reduced acuity)
3) RAPD
4) pain on eye movement
Is optic neuritis unilateral or bilateral?
Unilateral
Management of optic neuritis?
1) Urgent ophthalmology input.
2) High dose steroids.
What imaging can help to predict which patients with optic neuritis will go on to develop MS?
MRI
MS can cause eye movement abnormalities.
Give some features of MS causing eye movement abnormalities
1) Diplopia & nystagmus (can lead to oscillopsia): caused by lesions to the oculomotor (CN III), trochlear (CN IV) or abducens (CN VI)
2) Internuclear ophthalmoplegia (characterised by impaired adduction of ipsilateral eye with nystagmus of contralateral abducting eye): caused by lesion to medial longitudinal fasciculus
3) Conjugate lateral gaze disorder: caused by lesion in the abducens (CN VI)
What is internuclear ophthalmoplegia in MS caused by?
Caused by a lesion in the medial longitudinal fasciculus
What characterises internuclear ophthalmoplegia?
1) impaired adduction in ipsilateral eye
2) nystagmus of contralateral abducting eye
What is a conjugate lateral gaze disorder?
When looking laterally in the direction of the affected eye, the affected eye will not be able to abduct. For example, in a lesion involving the left eye, when looking to the left, the right eye will adduct (move towards the nose), and the left eye will remain in the middle.
What causes a conjugate lateral gaze disorder in MS?
CN VI (abducens) lesion
Multiple sclerosis may present with focal weakness.
Give some examples of this
1) Incontinence
2) Horner syndrome
3) Facial nerve palsy
4) Limb paralysis
5) Ataxia
Multiple sclerosis may present with focal sensory symptoms.
Give some examples of this
1) Trigeminal neuralgia
2) Numbness
3) Paraesthesia (pins and needles)
4) Lhermitte’s sign
What is Lhermitte’s sign?
Electric shock sensation that travels down the spine and into the limbs when flexing the neck.
It is caused by stretching the demyelinated dorsal column.
What does Lhermitte’s sign indicate in MS?
It indicates disease in the cervical spinal cord in the dorsal column.
A lesion where in MS can cause sensory ataxia?
Dorsal columns:
+ve Romberg’s
Pseudoathetosis
What is pseudoathetosis?
Involuntary writhing movements
2 important investigations in MS?
1) MRI scans
2) Lumbar puncture
Purpose of a lumbar puncture in MS?
Detect oligoclonal bands in CSF
Management of an acute relapse of MS?
High dose steroids –> oral or IV methylprednisolone
What steroid is indicated in acute flare of MS?
Methylprednisolone
What is often used 1st line for preventing MS relapse?
natalizumab
What can be given to manage oscillopsia in MS?
Gabapentin or memantine
What can be given to manage urge incontinence in MS?
Antimuscarinic medications e.g., solifenacin
What can be given to manage neuropathic pain in MS?
Amitriptyline or gabapentin
What can be given to manage spasticity in MS?
Baclofen or gabapentin
Management of fatigue in MS?
amantadine, modafinil or SSRIs
Before prescribing anticholinergics for bladder dysfunction in MS, what should you do?
Get an US of bladder first to assess bladder emptying - anticholinergics may worsen symptoms in some patients
What is the most common type of MND?
Amyotrophic lateral sclerosis (ALS)
What are 4 types of MND?
1) Amyotrophic lateral sclerosis (ALS)
2) Progressive bulbar palsy
3) Progressive muscular atrophy
4) Primary lateral sclerosis
What does progressive bulbar palsy primarily affect?
The muscles of talking and swallowing (the bulbar muscles).
Weakness in MND typically affects what first?
Upper limbs
Signs in MND?
Mix of UMN & LMN signs.
UMN:
- increased tone or spasticity
- brisk reflexes
- upgoing plantar
LMN:
- muscle wasting
- reduced tone
- fasciculations
- reduced reflexes
What is the most common presenting symptom in ALS?
Asymmetric limb weakness
Does MND affect affect external ocular muscles?
No
Investigations in MND?
1) Nerve conduction studies –> will show normal motor conduction and can help exclude a neuropathy
2) Electromyography: shows a reduced number of action potentials with increased amplitude
3) MRI: usually performed to exclude the differential diagnosis of cervical cord compression and myelopathy
What may an electromyography show in MND?
Reduced number of action potentials with increased amplitude
Which MND carries the worst prognosis?
Progressive bulbar palsy
Which MND has UMN signs only?
Primary lateral sclerosis
Which MND has LMN signs only?
Progressive muscular atrophy
Which MND carries the best prognosis?
Progressive muscular atrophy
1st line management of slowing MND progression?
Riluzole
What can be used to support breathing when the respiratory muscles weaken in MND?
NIV - usually BIPAP
What is preferred way to support nutrition and has been associated with prolonged survival in MND?
PEG feeding
MND prognosis?
poor: 50% of patients die within 3 years
What class of medication is ropimerole?
Dopamine agonist
What is Creutzfeldt-Jakob disease characterised by? (2)
1) rapid onset dementia
2) myoclonus
UMN or LMN in ALS?
Mixed
cognition in LBD?
Fluctuating (unlike other types of dementia)
What does a head impulse test result: Loss of fixation with corrective saccades when head turned to the right
indicate?
Peripheral cause of vertigo
When should you use cyclzine with caution?
in patients with HF as it may cause a fall in cardiac output
What are the features of multiple system atrophy?
1) parkinsonism
2) autonomic disturbance:
- ED (often early feature)
- postural hypotension
- atonic bladder
3) cerebellar signs
What does an MS diagnosis require?
MRI that shows demyelinating lesions that are disseminated in time & space
What is the most common hereditary peripheral neuropathy?
Charcot-Marie-Tooth disease
What does Charcot-Marie-Tooth disease result in?
Primarily motor loss
features of Charcot-Marie-Tooth disease?
- There may be a history of frequently sprained ankles
- Foot drop
- High-arched feet (pes cavus)
- Hammer toes
- Distal muscle weakness
- Distal muscle atrophy
- Hyporeflexia
- Stork leg deformity
What can acute withdrawal of levodopa precipiate?
Neuroleptic malignant syndrome
MRI with or without contrast in MS?
With contrast
What is spastic paresis?
Describes an UMN pattern of weakness in the lower limbs
Cause of spastic paresis?
Demyelination e.g. MS
