Neurology Flashcards
Huntington’s prognosis?
Progressive and incurable, results in death 20 years after the initial symptoms develop
Huntington’s genetics?
- AD
- Trinucleotide repeat of CAG
- Degeneration of cholinergic and GABAergic neurons in the striatum of the basal ganglia
- Defect in huntington gene (HTT) on Chromosome 4
Huntington’s features?
Typically after 35 y/o
1. Chorea
2. Personality changes
3. Dystonia
4. Saccadic eye movements
Guillain Barre typical organism?
Campylobacter jejuni
GBS key features?
Progressive, symmetrical, ascending weakness of the limbs. Sensory symptoms tend to be mild. Reflexes reduced or absent.
GBS other features?
- Hx of gastroenteritis
- Respiratory muscle weakness
- CN = diplopia, bilateral facial nerve palsy, oropharyngeal weakness common
- Autonomic = urinary retention, diarrhoea
- Papilloedema = reduced CSF resorption
GBS Ix?
- LP = raised protein with normal WCC in 66% (albuminocytologic dissociation)
- Nerve conduction studies = decreased motor nerve conduction velocity, prolonged distal motor latency, increased F wave latency
Stroke/TIA in carotid territory and pt not severely disabled?
Consider carotid endarterectomy
AF and stroke, when should anticoagulants be started?
14 days
Post-stroke when should statin be started?
If cholesterol > 3.5 and wait at least 48 hours due to risk of haemorrhagic transformation
Thrombolysis for acute stroke indications?
- Within 4.5 hours of onset of symptoms
- Haemorrhage excluded by imaging
When is thrombectomy offered for acute stroke?
- Within 6h symptoms onset and acute ischaemic stroke with confirmed occlusion of proximal anterior circulation (together with IV thrombolysis within 4.5h)
- 6-24 hours and confirmed occlusion of proximal anterior circulation, if there is potential to salvage brain tissue
- Consider < 24 hours both thrombectomy and thrombolysis for confirmed occlusion of the proximal posterior circulation (that is, basilar or posterior cerebral artery) and potential to salvage brain tissue
What functional status needs to be present for pts receiving thrombectomy?
Pre-stroke functional status of less than 3 on the modified Rankin scale and a score of more than 5 on the National Institutes of Health Stroke Scale (NIHSS)
Stroke secondary prevention?
- Clopidogrel
- Aspirin + MR dipyramidole if clopidogrel C/I
- MR dipyradimole if both aspirin and clopidogrel C/I
Carotid endarterectomy indication post-stroke?
- If suffered stroke or TIA in the carotid territory and are not severely disabled
- Should only be considered if carotid stenosis > 70% according ECST criteria or > 50% according to NASCET criteria
TIA definition?
A transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischaemia, without acute infarction.
TIA features?
Typically resolve within 1 hour
1. Unilateral weakness or sensory loss
2. Aphasia or dysarthria
3. Ataxia, vertigo, or loss of balance
4. Visual problems = amaurosis fugax, diplopia, homonymous hemianopia
TIA Rx?
Aspirin 300mg unless:
1. Patient has a bleeding disorder or is taking an anticoagulant (needs immediate admission for imaging to exclude a haemorrhage)
2. Already taking 75mg: continue current dose until r/v by specialist
3. Aspirin is C/I (d/w specialist team)
TIA specialist review?
- If >1 TIA/suspected cardioembolic source/severe carotid stenosis –> discuss need for admission/urgent observation with a stroke specialist
- Suspected TIA within last 7 days = assessment within 24h by stroke physician
- Suspected TIA >7 days = specialist assessment within 7d
TIA and driving?
Don’t drive until seen by specialist
TIA Neuroimaging?
- Don’t do CT unless clinical suspicion of an alternative diagnosis
- MRI should be done on same day as specialist assessment
TIA carotid imaging?
All pts should have urgent carotid doppler unless they are not a candidate for carotid endarterectomy
TIA Ix?
- Neuroimaging = MRI
- Carotid doppler
TIA Further Rx?
Clopidogrel
Neuropathic pain examples?
- DN
- Post-herpetic neuralgia
- Trigeminal neuralgia
- Prolapsed intervertebral disc
Neuropathic pain Rx?
- 1st line = Amitryptiline, duloxetine, gabapentin, pregabalin (if one doesnt work try another, typically only used as monotherapy)
- Tramadol as rescue therapy
- Topical capsaicin for localised neuropathic pain
- Pain management clinic if resistant
Trigeminal neuralgia Rx?
Carbamazepine 100mg BD and uptitrate slowly until pain is relieved
Parkinsons disease 1st line Rx?
- Motor symptoms affecting QoL = Levodopa
- Motor symptoms not affecting QoL = Dopamine agonist (non-ergot derived), levodopa or MAO-Bi
Levodopa mushkies?
- More motor symptom improvement
- More ADL improvement
- More motor complications
- Less specified s/e
Dopamine agonist mushkies?
- Less motor symptom improvement
- Less ADL improvement
- Less motor complications
- More specified s/e
MAO-B inhibitor mushkies?
- Less motor symptoms improvement
- Less ADL improvement
- Less motor complications
- Less specified s/e
Specified s/e?
- Excessive sleepiness
- Hallucinations
- Impulse control disorders
If pt continues to have symptoms despite optimal Levodopa Rx or has developed dyskinesia?
Add Dopamine agonist/MAO-B inhibitor/COMT inhibitor as adjunct
Amantadine evidence of motor symptoms or ADLs?
No evidence
Parkinsons and gastroenteritis risk?
Risk of acute Akinesia or Neuroleptic Malignant Syndrome
Parkinsons and impulse control disorder more common with?
- Dopamine agonist therapy
- History of previous impulsive behaviours
- History of alcohol consumption and/or smoking
Parkinsons and orthostatic hypotension what medication can be given?
Midodrine (periphral alpha adrenergic receptors to increase arterial resistance)
Drooling in Parkinsons Rx?
Glycopyrronium bromide
Levodopa usually given with?
Decarboxylase inhibitor e.g. carbidopa/benserazide = his prevents the peripheral metabolism of levodopa to dopamine outside of the brain and hence can reduce side effects
Levodopa s/e?
- Dry mouth
- Anorexia
- Palpitations
- Postural hypotension
- Psychosis
Levodopa adverse effects due to difficulty in achieving steady dose?
- End-of-dose wearing off
- On-off phenomenon
- Dyskinesias at peak dose
- These effects may worsen with time
If Parkinsons pt cannot take levodopa orally?
Dopamine agonist patch as rescue medication to prevent acute dystonia
Dopamine agonist examples?
- Bromocriptine
- Ropinorole
- Cabergoline
- Apomorphine
Ergot-derived dopamine receptor agonists?
Bromocriptine and cabergoline
Bromocriptine and cabergoline s/e?
Fibrosis = pulmonary, retroperitoneal and cardiac (therefore perform Echo, ESR, creatinine and CXR prior to Rx)
Dopamine receptor agonist s/e?
- Impulse control disorders
- Excessive daytime sleepiness
- Hallucinations
- Nasal congestion and postural hypotension
MAO-B inhibitor example?
Selegiline (inhibits the breakdown of dopamine secreted by the dopaminergic neurons)
Amantadine MOA and S/E?
- MOA = probably increases dopamine release and inhibits its uptake at dopaminergic synapses
- S/E = ataxia, slurred speech, confusion, dizziness, livedo reticularis
COMT inhibitor examples?
Entecapone and Tolcapone
(COMT is an enzyme involved in the breakdown of dopamine, and hence may be used as an adjunct to levodopa therapy)
Antimuscarinic examples?
- Procyclidine
- Benzotropine
Antimuscarinic parkinsons use?
Drug-induced parkinsonism
Most common psychiatric problem in Parkinsons?
Depression
Parkinsons disease definition?
Progressive neurodegenerative condition caused by degeneration of dopaminergic neurons in the substantia nigra. This results in a classic triad of features: bradykinesia, tremor and rigidity. Characteristically asymmetrical.
Parkinson’s epidemiology
2M:1F, mean age of diagnosis 65 y/o
Parkinsons tremor mushkies?
- Most marked at rest, 3-5 Hz
- Worse when stressed or tired, improves with voluntary movement
- Typically pill-rolling i.e. in thumb and index finger
Parkinsons autonomic dysfunction example?
Postural hypotension
Drug-induced parkinsonism features?
- Motor symptoms more rapid onset and bilateral
- Rigidity and rest tremor uncommon
Parkinsons Dx?
Usually clinical, but SPECT also
MND Features?
- Fasciculations
- Absence of sensory signs/symptoms
- Mixture of UMN and LMN signs
- Wasting of small hand muscles/tibialis anterior is common
- Does not affect external ocular muscles, no cerebellar signs
- Abdominal reflexes are usually preserved but sphincter dysfunction if present is a late feature
MND Dx?
Clinical
MND Ix?
- Nerve conduction studies = normal motor conduction, can help exclude neuropathy
- EMG = reduce number of action potentials with increased amplitude
- MRI = to exclude DDx of cervical cord compression and myelopathy
MS feature classification?
- Visual
- Sensory
- Motor
- Cerebellar
- Motor
MS Visual features?
- Optic neuritis = most common presenting feature
- Optic atrophy
- Uhthoff’s phenomenon = worsening of vision following rise in body temperature
- INO
MS sensory features?
- Pins/needles
- Numbness
- Trigeminal neuralgia
- Lhermitte’s syndrome = paraesthesiae in limbs on neck flexion
MS motor features?
Spastic weakness = most commonly seen in legs
MS cerebellar features?
- Ataxia = more often seen during an acute relapse
- Tremor
MS other features?
- Urinary incontinence
- Sexual dysfunction
- Intellectual deterioration
Phenytoin MOA?
Bind to sodium channels increasing their refractory period
Phenytoin s/e classification?
- Acute
- Chronic
- Idiosyncratic
- Teratogenic
Phenytoin P450?
Inducer
Phenytoin acute s/e?
- Initial = dizziness, diplopia, nystagmus, slurred speech, ataxia
- Later = confusion, seizures
Phenytoin chronic s/e?
- Common = gingival hyperplasia, hirsutism, coarsening of facial features, drowsiness
- Megaloblastic anaemia
- Peripheral neuropathy
- Enhanced Vitamin D metabolism causing osteomalacia
- Lymphadenopathy
- Dyskinesia
Phenytoin idiosyncratic s/e?
- Fever, rash (incl. TEN)
- Hepatitis, aplastic anaemia
- Dupuytren’s contracture
- Drug-induced lupus
Phenytoin teratogenic s/e?
A/w cleft palate and congenital heart disease
Phenytoin monitoring?
No routine monitoring needed, but trough levels, immediately before dose should be checked if:
1. Adjustment of phenytoin dose
2. Suspected toxicity
3. Detection of non-adherence to the prescribed medication
Status epilepticus definition?
- Single seizure > 5min
- > =2 seizures within a 5 min period without the person returning to normal between them
Status epilepticus Rx?
- 1st line = IV lorazepam, may be repeated once after 10-20 mins
- 2nd line = phenytoin or phenobarbital infusion
- Refractory (45 mins from onset) = induction of GA
Migraine management principles?
Serotonin agonists used for acute treatment, antagonists used in prophylaxis
Migraine acute Rx?
- 1st line = Oral triptan + NSAID/Paracetamol
- 12-17 y/o = consider nasal triptan
- If above not tolerated –> non-oral preparation of metoclopramide/prochlorperazine and consider adding a non-oral NSAID or triptan
Migraine prophylaxis?
Offered if experiencing 2 or more attacks per month: effective in about 60%
1. Topiramate/propranolol first line (Propranolol should be used in preference to topiramate in women of child bearing age as it may be teratogenic and it can reduce the effectiveness of hormonal contraceptives)
2. If these measures fail, up to 10 sessions of acupuncture over 5-8 weeks
3. Riboflavin 400mg OD may be effective in reducing migraine frequency and intensity
Predictable menstrual migraine Rx?
Zolmatriptan (2.5mg BD/TDS) or Frovatriptan (2.5mg BD) as mini-prophylaxis
Tuberous sclerosis inheritance?
AD
Tuberous sclerosis feature classification?
- Cutaneous
- Neurological
- Others
Tuberous sclerosis cutaneous features?
- Ash leaf spots which fluoresce under UV light
- Shagreen patches over lumbar spine
- Adenoma sebaceum in butterfly distribution over nose
- Subungual fibromata
- Cafe au lait spots
Tuberous sclerosis neurological features?
- Developmental delay
- Epilepsy
- Intellectual impairment
Tuberous sclerosis other features?
- Retinal hamartomas
- Rhabdomyomas of the hart
- Brain = Gliomatous changes can occur in brain lesions
- Kidneys = Polycystic kidneys, renal angiomyolipomata
- Lung = Lymphangioleiomyomatosis: multiple lung cysts
Epilepsy and DVLA?
- 1st unprovoked/isolated seizure = 6m off if brain imaging and EEG ok. If either abnormal then 12m off
- Established epilepsy/multiple unprovoked seizures = may get DL if seizure free for 12m, if there have been no seizures for 5y an until 70 license is usually restored
- Withdrawal of epilepsy medication = should not drive when being withdrawn and 6m after last dose
Syncope and driving?
- Simple faint = no restriction
- Single episode, explained and treated = 4 weeks off
- Single episode, unexplained = 6m off
- > = 2 episodes = 12m off
Stroke/TIA and driving?
1m off, may not need to inform DVLA if no residual neurological deficit
Multiple TIAs over short period of time and driving?
3m off and inform DVLA
Craniotomy and driving?
1y off
Narcolepsy/cataplexy and driving?
Cease driving on Dx, can restart once ‘satisfactory control of symptoms;
Chronic neurological disorder e.g. MS/MND and driving?
DVLA should be informed, complete PK1 form (application for driving licence holders state of health)
Sodium valproate P450?
Inhibitor
Sodium valproate teratogenicity?
Neural tube defects and neurodevelopmental delay
Sodium valproate s/e?
- GI = nausea, increased appetite, weight gain, hepatotoxicity, pancreatitis
- Derm = alopecia, regrowth may be curly
- Neuro = ataxia, tremor
- Haem = thrombocytopenia
- Metabolic = hyponatraemia, hyperammonemic encephalopathy (L-carnitine can be used as Rx if this develops)
Encephalitis main cause?
HSV-1 responsible in 95% in adults, typically affects temporal and inferior frontal lobes
Encephalitis Ix?
- CXF = lymphocytosis, elevated protein
- PCR for HSV
- Neuroimaging (MRI better) = medial temporal and inferior frontal changes e.g. petechial haemorrhages, normal in 1/3rd pts
- EEG = lateralised periodic discharged at 2 Hz
Encephalitis Rx?
IV Aciclovir
Stroke assessment scoring system?
ROSIER (assess hypoglycaemia first), stroke is likely if score > 0
Stroke Ix?
Non-contrast CT head
Bell’s Palsy definition?
Acute, unilateral, idiopathic, facial nerve paralysis. Peak incidence 20-40 y/o, condition more common in pregnant women
Bell’s palsy features?
- LMN (forehead affected)
- Post-auricular pain may precede paralysis
- Dry eyes
- Altered tast, hyperacusis
Bell’s palsy Rx?
- Oral prednisolone within 72h
- Can add antivirals for severe facial palsy
- Artificial tears and eye lubricants, tape eye closed if unable to close at bedtime (to prevent exposure keratopathy)
Bell’s palsy f/up?
- If not improvement after 3w –> refer urgently to ENT
- Long-standing weakness of several months –> refer to plastics
Bell’s palsy prognosis?
- Most make full recovery within 3-4 months
- If untreated around 15% have permanent moderate to severe weakness
Peripheral neuropathy cause classification?
- Predominantly motor loss
- Predominantly sensory loss
Predominantly motor peripheral neuropathy causes?
- Infection = diphtheria
- Inflammation = GBS, HSMN (CMT), CIDP
- Metabolic = Porphyria, lead poisoning
Predominantly sensory peripheral neuropathy causes?
- Infection = Leprosy
- Inflammation = Amyloidosis
- Metabolic = Diabetes, B12 deficiency, alcohol, uraemia
Alcoholic neuropathy mushkies?
- Secondary to both direct toxic effects and reduced absorption of B vitamins
- Sensory symptoms typically present prior to motor symptoms
Vitamin B12 deficiency mushkies?
- SCDSC
- Dorsal column usually affected first (joint position, vibration) prior to distal paraesthesia
Cluster headache RFs?
- 3M:1F, smokers
- Alcohol may trigger an attack
- Appears to be a relation to nocturnal sleep
Cluster headache features?
- 1/2 a day, each episode 15m-2h
- Clusters last 4-12 weeks
- Intense sharp, stabbing pain around one eye
- Restless and agitated during attack
- Redness, lacrimation, lid swelling
- Nasal stuffiness (rhinorrhoea)
- Miosis and ptosis in a minority
Cluster headache Rx?
- Acute = 100% Oxygen (80% response rate within 15 mins), S/C Triptan (75% response rate within 15 minutes)
- Prophylaxis = Verapamil
- Seek neuro advice for imaging
Cluster headache is a type of?
Trigeminal autonomic cephalgia
Trigeminal autonomic cephalgia types?
- Cluster headache
- Paroxysmal hemicrania
- Short-lived unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT)
Paroxysmal hemicrania Rx?
Indomethacin
Brain abscess Rx?
- Surgery = craniotomy, debride abscess
- Abx = IV 3rd gen ceph + metronidazole
- ICP management = dexamethasone
When to usually start antiepileptics?
After second epileptic seizure
When to start antiepileptics after 1st seizure?
- Neurological deficit
- Brain imaging shows structural abnormality
- EEG shows unequivocal epileptic activity
- Pt/family/carers consider risk of having a further seizure unacceptable
Male GTC Rx?
Sodium Valproate
Female GTC Rx?
Lamotrigine or Levetiracetam