Dunedin-Neurology Flashcards
How to diagnose Parkinson’s disease?
2 of the 3 features:
Bradykinesia + resting tremor OR rigidity
What are some motor symptoms in parkinsons that are not levodopa responsiveness?
voice change
freezing
gait ignition failure
What are the key prodomal features of parkinsons?
*RBD (REM sleep behaviour disorder) –> movements of body or limbs associated with dreaming with at least one of the following
- potentially harmful sleep behaviour
- dreams that appear to be acted out
- sleep behaviour that disrupts sleep continuity
*hyposmia
*anxiety
* constipation
What are some mutations related to Parkinsons disease?
GBA (glucocerebrosidase)
LRRK2
Describe the order of pathological changes in PD
starts in the medulla, and the olfactory bulb, then spreads upwards to substantial nigra, then finally into the cortex
Where is levodopa absorbed? What is the half life.
absorption in duodenum and jejunum. it competes with amino acids for gut absorption
therefore relies on gastric emptying.
half life 1.5 hours
What can cause increased plasma concentration/dose of levodopa?
advanced age
low body weight
What are some S/E of levodopa?
nausea
orthostatic hypotension
hallucinations
sleepiness and sleep attacks
confusion
motor fluctuations and dyskinesia
contributes to impulse control disorders
What are some medications for the treatment of PD?
What is the MOA of dopamine agonist in parkinsons disease?
directly stimulate the post-synaptic dopamine receptors
longer half life than levodopa
but less potent and greater S/E than levodopa
e.g. apomorphine, pramipexole, ropinirole, rotigotine, piribedil
What are S/E of dopamine agonist?
*nausea
*orthostatic hypotension
*confusion and *hallucinations
*sleepiness/sleep attacks
*peripheral oedema, ankle swelling, facial oedema
*skin irritation/rash (rotigotine)
*impulse control disorders
How to manage impulse control disorders when using dopamine agonists?
reduce or change dopamine agonist
this is associated with things like pathological gambling, hypersexuality, compulsive (binge) eating, compulsive shopping
What is punding?
often due to taking too much dopamine
often associated with marked dyskinesias and off-state dysphoria and with over-use of levodopa
mx: reduce levodopa
What is the MOA of MOA inhibitors such as rasagiline
prevents apoptotic cell death
irreversible inhibitor
MAO-type b- 80% of all MAOs in the brain
half life is 40 days
What is “wearing off” in parkinsons disease using Levodopa and how to treat?
Dose starts to wear off
treat:
* add entacapone or rasagiline
*decrease dose intervals
* increase levodopa dose size
* add dopamine agonist
Describe levodopa-induced dyskinesia
Peak dose: 30-60 min after levodopa, mainly chorea, entire body or upper half, person not aware
Treat: reduce levodopa dose size, add amantadine, add dopamine agonist and reduce levodopa, stop entacapone
End of dose: 3-4 hours post levodopa, or early morning, dystonia, often foot/leg, often painful
Treat: add entacapone or selegiline, decrease dose interval, increase levodopa dose size, add amantadine, add dopamine agonist
What are COMT inhibitors and difference between them and S/E
prolong action of levodopa
entacapone and tolcapone
tolcapone more likely to cause liver problem however it can cross blood brain barrier
S/E: insomnia, lived reticular, confusion, leg oedema, blurred vision
What is treatment of RBD (rapid eye movement sleep disorder)?
1) clonazepam
2) melatonin
3) small case series suggest: Pramipexole, donepezil, cannabinoids
How to treat dementia in parkinsons disease
Cholinesterase inhibitor:
- rivastigmine ,donezpezil
memantine
How to treat psychosis in Parkinson’s?
Benign hallucinations –> don’t treat
Paranoid psychosis –> quetiapine, reduce PD drugs, cholinesterase inhibitors (donepezil) if dementia/confusion, clozapine if ongoing psychosis
What are some advanced therapies for Parkinsons disease?
*apomorphine subcutaneous infusions
* DuoDopa Gel via PEG-J placement
*pallidotomy
* deep brain stimulation
What is the selection of patients for deep brain stimulation in Parkinson’s disease
1) typical PD and levodopa-responsiveness
2) medically healthy
3) No dementia
4) no psychosis or severe hallucinations
5) <70 years
What is the difference between MSA-C and MSA-P?
Automonic dysfunction + motor features (parkinsonsism or ataxia)
MSA-C: multiple system atrophy, the cerebellar predominant form (nystagmus, dysarthria, ataxia)
MSA-P: the parkinsons predominant form (symmetric rigidity, little tremor, poor postural reflexes)
- erectile failure, urinary incontinence, postural hypotension
What do you see in the brain for Multiple system atrophy?
alpha synucleiopathy
hot cross bun sign: atrophy of pons and cerebellum
MCP atrophy
putaminal rim sign
increased diffusion putamen
Is Progressive Supranuclear palsy a tauopathy?
Yes
neurofibrillary tangles (made up of tau) in brain stem, flame-shaped NFTs, coiled bodies, neuronal loss and gloss
What are the types of PSP?
1) Richardson’s syndrome: classic features of PSP early onset falls, slow vertical saccades, supra nuclear vertical gaze palsy, postural instability, frontal dementia, axial rigidity
2) PSP-parkinsons: asymmetric onset, tremor, response to levodopa, better prognosis
What is the radiological sign of PSP?
hummingbird or ‘kind penguin’ sign ie mid brain atrophy
Is Corticobasal syndrome a tauopathy?
yes
What is a common presentation of corticobasal syndrome?
rigid jerking arm
apraxia, frontal lobe dementia
+/- supra nuclear gaze palsy but not as severe as PSP
What are core features of dementia with Lewy bodies?
dementia has to start before or within a year of motor symptoms
core features (need 2)
a) fluctuating cognition
b) recurrent visual hallucinations
c) parkinsonsim
Suggestive
a) REM sleep behaviour disorder
b) severe neuroleptic sensitivity
What chromosome is the Huntingtin gene on?
Chromosome 4
CAG repeat (>40 repeats for sure, 36-39 increased risk, 6-25 unaffected)
What are the main features of Huntingtons disease?
1) involuntary movements (chorea, dystpnoa and Parkinsonism)
2) Behavioural disorders
3) cognitive impairment and dementia
Age of onset is based on size of CAG repeat expansion. True or false?
True
Treatment of Huntington?
symptomatic:
atypical antipsychotics
- tetrabenazine
- risperidone, olanzpine
- aripriprazole
antidepressants
What is the diagnostic criteria for restless legs syndrome?
1) an irresistible urge to move the legs, usually but not always accompanied by uncomfortable and unpleasant sensations in the legs
2) Worse during rest or inactivity
3) symptoms partially or totally relieved by movement
4) worse in evening or night
5) no other conditions (myalgia, venous stasis, leg oedema, arthritis, leg cramps, positional discomfort, habitual foot tapping)
Describe anti-LGL1 encephalitis
a type of limbic encephalitis
faciobrachial dystonic seizures
How to treat NMDA receptor antibody-mediated encephalitis?
corticosteroids
IVIG
plasma exchange
rituximab
cyclophosphamide
What are common features of limbic encephalitis?
memory impairment
Describe common types of limbic encephalitis
LGL1 (most common)- hyponatraemia, faciobracial seizures
GABABR and AMPAR
What is the MRI finding in limbic encephalitis
Mesial temporal lobe hyperintensty
What are the characteristics of DPPX antibodies encephalitis?
onset subacute to chronic
weight loss and GI symptoms
cognitive dysfunction
CNS hyper excitability (hypereflexia, myoclonus)
ataxia
eye movement disorder
What is Lhermitte’s and Uhthoff’s symptoms?
Lhermittes: transient sensation of an electric shock that extends down the spine and extremities upon flexion and/or movement of the neck.
Uhthoff: transient worsening of neurological function lasting less than 24 hours that can occur in multiple sclerosis patients due to increases in core body temperature
What are the types of multiple sclerosis?
What is the best imaging for MS?
MRI
GAD enhancement shows up “active lesions”
What is the characteristic appearance of MS on neuroimaging?
– periventricular, corpus callosum, centrum semiovale
– radiating out from corpus callosum = Dawson’s fingers
– brainstem, cerebellum
– hyperintense on T2 & Proton Density (PD) sequences
– hypointense on T1 (black holes) = axonal damage
What does ring-like enhancement suggest in MS lesions?
peripheral inflammation & complete central demyelination ( = reactivation at periphery of a chronic lesion).
What are things we can use in the diagnose of MS?
*MRI
*Evoked potential (EPs)
*Central motor conduction time (CMCT)
*Lumbar puncture - CSF- oligoclonal bands +ve in CSF but NOT In serum. Increased CSF IgG synthesis
What are some Multiple Sclerosis mimics?
*NMOSD & MOGAD
*Inflammatory disease (SLE, Sjogrens, PAN, Behcets etc)
*Infectious disease
*Granulmonatous disease
* diseases of myelin
*CADASIL
What is true about pregnancy in MS?
relapse rate reduced during pregnancy, especially in 3rd trimester
increase in relapse rate in 6 months after delivery
breastfeeding decreases early relapse rate
What are poor prognostic factors of MS?
Male
>40 years
What are MRI features that suggest poor prognosis of MS?
*high T2 lesion load
*>2 GAD enchanting lesions
*>T1 hypointense lesions
*early atrophy
* infratentorial as opposed to supratentorial lesions
Describe the treatment of MS
Acute: methylpred. Avoid pred in optic neuronitis
Continuous
- low efficacy: IFN, GA (glatiramer acetate), teriflunomide
- medium efficacy: S1PR (sphingosine-1-phosphate receptor eg ozanimod, pronesimod), DMF (dimethyl fumarate)
- high efficacy: Natalizumab (akpha-4-integrin blocker), B cell therapies (ocrelizumab, ofatumumab)
- alemtuzumab anti-cd52 is used but less often
Pulse
- medium efficacy: cladribine
- high efficacy: alemtuzumab, HSCT
What are side effects of alemtuzumab (CD52)
Profound depletion of T cells (for >1 year), profound depletion of B cells
autoimmune thyroid disaese
Immune mediated conditions including hepatitis and haemophagocytic lymphohistiocytosis, bleeding in lungs, MI, stroke, arterial dissection and severe neutropaenia
What is the MOA of fingolimod?
Decreases ability of lymphocytes to enter CNS by preventing the
egress of lymphocytes from lymphatic tissues.
Down regulates four sphingosine-1-phosphate receptor subtypes
What is the MOA of teriflunomide?
Inhibits pyrimidine synthesis (dihydroorotate dehydrogenase inhibitor)
a metabolite of leflunamide
S/E: HTN, LFT and RBS abnormal, alopecia and diarrhoea
Is stem cell transplant an option for MS?
Possibly
What antibodies occur in neuromyelitis optica spectrum disorder (NMOSD)
aquaporin 4 abs
in high conc in foot processes of astrocytes along endothelial lining of blood brain barrier
pathology: complement mediated destruction of astrocytes with secondary demyelination
What are spinal cord MRI abnormalities noted in NMOSD?
longitudinally extensive (>3 segments) spinal cord MRI abnormalities
(LETM= longitudinally extensive transverse myelitis)
often have optic nerve disease
What is the CSF like in NMOSD?
significant pleocytosis
What is the pathophysiology of NMOSD?
complement mediated destruction of astrocytes with secondary demyelination
What antibody is involved in Myelin Oligodendrocyte Glycoprotein Associated Disease (MOGAD)?
anti-MOG