Neurology Flashcards
What are the most common types of dementia?
- Alzheimer’s
- Vascular
- Dementia with Lewy-body
- Frontotemporal dementia (a.k.a Pick’s disease)
Describe the pathophysiology of Alzheimer’s
- Mostly affects temporal lobes
- Senile plaques (deposits of beta-amyloid outside of neurons)
- Neurofibrillary tangles (aggregation of hyperphosphorylated tau proteins inside neurons which cause necrosis of neural tissue)
What are key clinical features of Alzheimer’s?
- Early impairment of memory
- Short-term memory loss/difficultly learning new information
- 4 A’s = amnesia, aphasia, agnosia, apraxia
What are investigations for Alzheimer’s?
- Cognitive assessment
- Memory assessment
- Bloods (TFTs/B12)
- CSF Tau studies
- CT/MRI
What medications can be used for patients with dementia?
Mostly for Alzheimer’s:
- Acetylcholinesterase inhibitors e.g. donepezil, rivastigmine, galantamine
- N-methyl-D-aspartic acid receptor antagonists (NMDA) e.g. memantine (for memory loss)
- Antipsychotics
What is the difference between dementia and delirium?
Dementia = slowly progressive changes with limited fluctuation. Attention is usually intact and very early memories may be preserved
Delirium = acute, transient and usually reversible changes. Often an associated acute illness
What are the clinical features of delirium?
- Acute onset
- Fluctuating symptoms
- Disturbance in awareness and attention
- Disturbance in cognition
- Evidence of an organic cause
What are clinical features of hypoactive delirium?
- Lethargy
- Apathy
- Excessive sleeping
- Inattention
- Withdrawn
- Motor retardation
- Drowsy
- Unrousable
What are clinical features of hyperactive delirium?
- Agitation
- Aggression
- Restlessness
- Rapidly distracted
- Wandering
- Delusions
- Hallucinations
What are the investigations for delirium?
- Bloods (FBC/U&Es/TFTs/LFTs/B12 and folate/coagulation and INR/calcium/glucose/blood cultures)
- Urine dipstick
- MRI/CT
- CXR
What criteria is used for delirium?
DSM-5 criteria:
- Disturbance in awareness
- Acute onset
- Disturbance in cognition
- Not better explained by a pre-existing established or evolving neurocognitive disorder
- Absence of severely reduced GCS
- Evidence of organic cause
What is the management for delirium?
- Determine/treat underlying cause
- Rapid tranquilisation (benzodiazepines e.g. lorazepam/antipsychotics e.g. haloperidol, olanzapine)
- De-escalation methods (maintain adequate distance/move to safe, low-stimulant environment/use non-threatening verbal and non-verbal techniques/involve relatives or people close to patient)
Describe the pathophysiology of vascular dementia
- Subcortical VD (disease affected small vessels of brain)
- Stroke-related VD (following large cortical stroke)
- Single/multi-infarct VD (following single/multiple small strokes)
Describe the pathophysiology of Lewy-Body dementia
- If dementia symptoms 12 months before motor symptoms
- Histopathological findings of intracytoplasmic inclusions (Lewy bodies) that contain alpha-synuclein
- Lewy bodies lead to reduced levels of acetylcholine and dopamine in the brain
Describe the pathophysiology of frontotemporal dementia
- Tissue deposition of aggregated proteins (phosphorylated tau or transactive response DNA-binding protein 43)
- Atrophy around frontal/temporal lobes
What are general clinical features of dementia?
- Slow onset sx
- Lack of insight
- Cognitive impairment
- Behavioural and psychological sx
- Decreased ability to carry out ADLs
What are key clinical features of vascular dementia?
- Stepwise decline in function
- Gait/attention/personality changes
- Focal neurological symptoms e.g. aphasia/weakness
What are key clinical features of Lewy-Body dementia?
- Fluctuating cognitive impairment
- Parkinsonism sx (tremor/rigidity/bradykinesia/postural instability)
- Falls/syncope/hallucinations
- Sleep disturbances/restlessness at night
What are key clinical features of frontotemporal dementia?
- Personality changes and behavioural disturbances (disinhibition)
- Memory and perception relatively preserved
- Stereotypical, repetitive, compulsive behaviour/emotional blunting/abnormal eating/language problems
What is sundowning?
Increase in certain symptoms (e.g. distress/agitation/hallucinations/delusions) in dementia patients that often occur in the late afternoon/evening
What are investigations for dementia?
- Exclude alternative diagnoses
- Cognitive assessments
- Bloods
- ECG
- Virology
- Syphilis testing
- CXR
- CT/MRI head
What are some differential diagnoses for dementia?
- Depression
- Drugs with anticholinergic effects
- Delirium
What is the management for dementia?
- Assess capacity
- Inform DVLA
- Cognitive stimulation therapy
- Cognitive rehabilitation
- Reminiscence work
- Admiral nurses
- Reduce risk factors (e.g. for VD) - stop smoking/exercise/statins/etc.
- Medications
What are risk factors for Parkinson’s?
- Age
- Male
- Pesticide exposure
Describe the pathophysiology of Parkinson’s
- Basal ganglia responsible for coordinating habitual movements
- Substantia nigra = part of basal ganglia that produce dopamine (needed for functioning of basal ganglia)
- Parkinson’s = gradual fall in production of dopamine
What are the clinical features of Parkinson’s?
- Unilateral symptoms (bilateral suggests drug-induced)
- Resting ‘pill rolling’ tremor better on voluntary movement
- Cogwheel rigidity
- Bradykinesia (shuffling gait/small handwriting/hypomimia)
What investigation can differentiate Parkinson’s Disease and benign essential tremor?
DAT scan:
- Normal in tremor
What is the management for Parkinson’s?
- FIRST LINE = Levodopa + peripheral decarboxylase inhibitors (Carbidopa/benserazide)
- Catechol-o-methyltransferase (COMT) inhibitors e.g. entacapone
- Dopamine agonists e.g. bromocriptine/cabergoline/pergolide
- Monoamine oxidase-B inhibitors e.g. selegiline/rasagiline
What are the side effects of excess dopamine?
- Dyskinesias (dystonia/chorea/athetosis)
- Treat with amantadine (glutamate antagonist)
What is an essential tremor and what is it associated with?
A type of action tremor (fine tremor) associated with older age
What are the clinical features of essential tremor?
- Fine tremor in hands/head/jaw/vocals
- Symmetrical
- More prominent with voluntary movement
- Worse when tired/stressed/caffeine
- Improved by alcohol
- Absent during sleep
What is the management for essential tremor?
- No treatment required if not causing issues
- Symptomatic relief = propranolol, primidone
Describe the pathophysiology of Huntington’s disease
- Autosomal dominant
- Increased CAG repeats on Huntington (HTT) gene on chromosome 4
- Caudate nucleus atrophy
- Inhibitory neurones in corpus striatum degenerate
- Lack of GABA
- Anticipation (successive generations have more repeats)
What are the clinical features of Huntington’s disease?
- Typically presents around 30-50
- Chorea
- Eye movement disorders
- Dysarthria
- Dysphagia
What are the investigations for Huntington’s disease?
- Genetic test
- MRI/CT = loss of striatal volume
What is the management for Huntington’s disease?
Symptomatic relief:
- Antipsychotics e.g. olanzapine
- Benzodiazepines e.g. diazepam
- Dopamine-depleting agents e.g. tetrabenzine
What are the complications of Huntington’s disease?
- Life expectancy = approx. 15-20 years after onset of sx
- Death due to respiratory disease
- Suicide
What are the most common types of motor neurone disease and what are the risk factors?
- Amyotrophic lateral sclerosis (ALS)
- Progressive bulbar palsy
- Genetics
- Smoking
- Exposure to heavy metals
- Pesticides
Describe the pathophysiology of motor neurone disease
- Loss of neurones in motor cortex, cranial nerve nuclei and anterior horn cells
- ALS = motor cortex, anterior horn (UMN + LMN)
- PBP = CN IX-XII (UMN + LMN)
- Progressive muscular atrophy = Anterior horn (LMN)
- Primary lateral sclerosis = UMN
What are the clinical features of motor neurone disease?
- No sensory sx
- Progressive weakness of muscles in limbs/trunk/face/speech –> clumsiness
- Often first noted in upper limbs
- Increased fatigue when exercising
- Dysphagia/chewing difficulties
What are the specific clinical features of upper and lower motor neurone disease?
Upper MND = hypertonia/spasticity, clonus, brisk reflexes
Lower MND = muscle wasting, hypotonia, fasciculations, reduced reflexes
What is the management for motor neurone disease?
- ALS = riluzole (slows progression)
- Non-invasive ventilations
- End of life care
What are risk factors for multiple sclerosis?
- Female
- Genetics
- Epstein-Barr virus
- Low vitamin D
- Smoking
- Obesity
Describe the pathophysiology of multiple sclerosis
- Affects CNS (oligodendrocytes)
- Inflammation and infiltration of immune cells damages myelin
- Causes demyelination
What are the clinical features of multiple sclerosis?
- Optic neuritis due to demyelination of optic nerve (reduced vision, central scotoma, pain on movement, impaired colour vision, pupil defect)
- Eye movement abnormalities due to lesions in abducens nerve (diplopia, internuclear ophthalmoplegia, conjugate lateral gaze disorder)
- Weakness (Bell’s palsy, Horner’s, limb paralysis, incontinence)
- Sensory sx (trigeminal neuralgia, numbness, MS hug, paraesthesia, Lhermitte’s sign (electric shock))
- Ataxia
What is optic neuritis?
Inflammatory optic neuropathy affecting one or both optic nerves
- Typical (a.k.a demyelinating) is the most common type
What are the clinical features of optic neuritis?
- Reduced acuity
- RAPD (relative afferent pupillary defect)
- Dyschromatopsia (colour blindness where 2/3 fundamental colours seen)
- Typical patient = Young, Caucasian woman presenting with acute unilateral vision loss associated with painful eye movements and colour desaturation
What are the investigations for multiple sclerosis?
- McDonald’s criteria
- MRI = lesions/areas of T2 hyperintensity
- LP = oligoclonal bands in CSF
- Fundoscopy = often normal but may show optic disc swelling (optic neuritis)
What is McDonald’s criteria?
For MS diagnosis
- 2+ attacks, 2+ lesions
- 1+ attacks,1 lesion, dissemination in space on MR
- 1 attack, 2 lesions, dissemination in time on MR
- 1 attack, 1 lesion, dissemination in space and time
- 1 year of disease progression, at least 2 out of 3 criteria (dissemination in space in the brain/dissemination in space in the spinal cord based on 2 or more T2 lesions/positive CSF)
What does disseminated in space mean for McDonald’s criteria (MS)?
In different regions = juxtacortical, subcortical, infratentorial and spinal cord
What is the management for multiple sclerosis?
- Steroids
- Interleukins/inflammatory cytokines/immune cells
- Symptomatic relief (amitriptyline/antidepressants/anticholinergics e.g. tolterodine, oxybutynin/anti-spasticity e.g. baclofen/gabapentin)
What is given to patients experiencing a relapse of MS?
500mg methylprednisolone orally for 5 days or IV for 3 days
What does myasthenia gravis have an association with?
Thymomas (tumours of thymus gland)
Describe the pathophysiology of myasthenia gravis
- Acetylcholinesterase receptor (Ach-R) antibodies
- Muscle-specific kinase (MuSK) antibodies
- Low-density lipoprotein receptor-related protein 4 (LRP4) antibodies
- Antibodies affect acetylcholine receptors and prevent uptake of the neurotransmitter acetylcholine
What are the clinical features of myasthenia gravis?
- Fatiguability
- Weakness that worsens with activity and improves with rest
- Proximal muscles more commonly affected
- Diplopia/ptosis/facial weakness
- Swallowing/chewing difficulty
- Slurred speech
What are the investigations for myasthenia gravis?
- Check fatiguability (repeated blinking/upward gazing/abduction of arm)
- Antibodies
- Edrophonium test
What is the edrophonium test?
- Investigation for myasthenia gravis
- IV dose of edrophonium chloride given
- Blocks enzymes that break down acetylcholine - Symptoms briefly relieved
What is the management for myasthenia gravis?
- Acetylcholinesterase inhibitors e.g. pyridostigmine, neostigmine (long-acting)
- Prednisolone/azathioprine
- Monoclonal antibodies e.g. rituximab, eculizumab
- Thymectomy
What is a complication of myasthenia gravis?
Myasthenia crisis:
- Acute worsening of symptoms often triggered by another illness
- Can lead to respiratory failure
- Management = IV immunoglobulins and plasmapheresis +/- ventilation
When does Guillain-Barre syndrome typically occur?
Following an infection (e.g. gastroenteritis) - associated with C. Jejuni, CMV, EBV
What are the clinical features of Guillain-Barre syndrome?
- History of recent infection
- Symmetrical ascending weakness
- Reduced reflexes
- Peripheral loss of sensation
What are the investigations for Guillain-Barre syndrome?
- Nerve conduction studies = reduced
- LP for CSF = raised protein, normal cell count/glucose
What is the management for Guillain-Barre syndrome?
- IV immunoglobulins
- Supportive care
- Plasmapheresis (alternative to IV Ig)
- VTE prophylaxis
What are the complications of Guillain-Barre syndrome?
- PE –> respiratory failure
- Locked-in syndrome
What are the most common causes of viral meningitis?
Viral meningitis more common and less severe
- Enteroviruses e.g. echovirus, coxsackie
- HSV
- Mumps virus
What are the most common causes of bacterial meningitis?
Bacterial meningitis less common and more severe
- Neonates = group B strep (strep. agalactiae), E. coli, listeria meningitis
- N. meningitis (a.k.a meningococcus), strep. pneumoniae
What are other causes of meningitis?
Fungal = cryptococcus, candida
What are the risk factors for meningitis?
- Student
- Recent travel
- Immunocompromised
- Pregnancy
- Extremes of ages
- Unvaccinated
What are the clinical features of meningitis?
- Fever
- Neck stiffness/pain
- N+V
- Headache
- Photophobia
- Altered consciousness
- Seizures
What is the main feature of meningococcal septicaemia?
- Non blanching rash –> infection has caused DIC and subcutaneous haemorrhage
What are the investigations for meningitis?
- LP for CSF
- Bloods/blood culture
- Kernig’s test
- Brudzinski’s test
How do you differentiate between viral and bacterial meningitis?
LP for CSF
- Appearance = cloudy (bacterial) or clear (viral)
- Protein = very high (bacterial), high/normal (viral)
- Glucose = low (bacterial), normal (viral)
- WCC = high neutrophils (bacterial), high lymphocytes (viral)
- Culture = bacteria (bacterial), negative (viral)
What is Kernig’s test?
Investigation for meningitis
- Patient lies on back with hip flexed and knee bent to 90 degrees
- Slowly try to extend knee whilst keeping hip flexed
- Meningitis = spinal pain/resistance to movement
What is Brudzinski’s test?
Investigation for meningitis
- Patient lies on back
- Lift head and neck off bed and flex chin to chest
- Positive = involuntarily flexion of hip and knees
What is the management for viral meningitis?
Aciclovir
What is the management for bacterial meningitis?
- Meningococcal septicaemia = IM/IV benzylpenicillin
- <3 months = cefotaxime + amoxicillin/ampicillin
- > 3 months = ceftriaxone
- Post exposure prophylaxis = ciprofloxacin/rifampicin
What is the most common complication of bacterial meningitis?
Sensorineural hearing loss - due to damage to the cochlear nerve or inner ear structures during inflammation
What are the most common causes of encephalitis?
- HSV (neonates = HSV-2, children = HSV-1)
- VZV
- CMV
- EBV
What are the clinical features of encephalitis?
- Fever
- Headache
- Encephalopathy
- Altered consciousness
- Altered cognition/behaviour
- Focal seizures
What are the investigations for encephalitis?
- LP for CSF
- CT/MRI
What is the management for encephalitis?
- HSV/VZV = aciclovir
- CMV = ganciclovir
What are the main components of a seizure?
- Prodrome = precedes seizures by hours to days - weird feeling
- Aura = right before - deja vu/strange smells/flashing lights
- Post-ictal = after seizure - headache/confusion/sore tongue/post-ictal Todd’s palsy (temporary weakness in motor cortex)
What are the features of a non epileptic seizure?
- Occurs in abnormal metabolic circumstances e.g. low Na+, hypoxia
- Last longer than epileptic seizures
- Do not occur in sleep
- No incontinence/tongue biting
- No muscle pain
What blood test can differentiate true seizures from pseudoseizures?
Prolactin - raised in true seizures
What is required for a diagnosis of epilepsy?
- At least 2 unprovoked seizures occurring more than 24 hours apart
- 1 unprovoked seizure and a high probability of further seizures
What are the investigations for seizures?
- EEG
- MRI
- ECG
- Bloods/electolytes/glucose/cultures/LP
What is the management for seizures/epilepsy?
Acute:
- Recovery position
- Place something soft under head
- Remove things that could cause injury
- Note start/end time of seizures
- Call ambulance if seizure lasts >5 mins
Medication:
- Sodium valproate/lamotrigine/carbamazepine/levetiracetam/ethosuximide
When is a diagnosis of epilepsy remission given?
Individuals who:
- Had an age-dependent epilepsy syndrome but are now past the applicable age
- Have remained seizure-free for at least 10 years off anti-seizure medications, provided that there are no known risk factors associated with high probability of future seizures
What is the main complication of seizures/epilepsy?
Status epilepticus - when seizure lasts >5 minutes or 2+ seizures without regaining consciousness
Management:
- ABCDE
- Community = buccal midazolam/rectal diazepam
- FIRST LINE = benzodiazepine - IV lorazepam
- After 2 attempts of benzodiazepine = IV phenytoin/sodium valproate/levetiracetam
- Third line = phenobarbital/general anaesthesia
What is sodium valproate used for and what are the side effects?
Epilepsy and bipolar disorder/mania
- Teratogenic
- Liver damage
- Hair loss
- Tremor
What is carbamazepine used for and what are the side effects?
Epilepsy and bipolar disorder/mania
- Agranulocytosis
- Aplastic anaemia
What is ethosuximide used for and what are the side effects?
Epilepsy
- Night tremors
- Rash
- N+V
What is lamotrigine used for and what are the side effects?
Epilepsy and bipolar disorder/mania
- DRESS syndrome = drug reaction with eosinophilia and systemic symptoms
- Leukopenia
- Stevens-Johnson syndrome (rare, severe skin reaction)
Describe tonic clonic seizures
A.k.a grand mal seizures
- Loss of consciousness
- Tonic (muscle tensing) and clonic (muscle jerking)
- Tongue biting/incontinence/groaning/irregular breathing
- First line management = sodium valproate
- Second line management = lamotrigine/carbamazepine
Describe myoclonic seizures
- Sudden brief muscle contractions
- Patient usually conscious
- Often happens in children as part of juvenile myoclonic epilepsy
- First line management = sodium valproate
- Second line management = Lamotrigine/levetiracetam/topiramate
Describe tonic seizures
- Sudden onset of increased muscle tone (entire body stiffens) - fall if patient standing
- Usually only lasts a few seconds
- First line = sodium valproate
- Second line = lamotrigine
Describe atonic seizures
A.k.a drop attacks
- Brief lapses in muscle tone
- Sudden loss of muscle strength
- Part/all of body becomes limp
- Usually last <3 minutes
- First line management = sodium valproate
- Second line management = lamotrigine
Describe absence seizures
- Common in children
- Blank expression/staring into space
- Abrupt return to normal
- Unaware of surroundings and won’t respond during episode
- Typically last 10-20 seconds
- Management = sodium valproate/ethosuximide
Describe temporal lobe seizures
- Affect hearing/speech/memory/emotions
- Hallucinations/memory flashbacks/deja vu/anxiety/automatisms
- First line management = lamotrigine/carbamazepine
- Second line management = sodium valproate/levetiracetam
Describe frontal lobe seizures
- Motor disturbances
- Jacksonian march
- Remains conscious
- Post-ictal Todd’s palsy
What are febrile convulsions and what are the risk factors?
- Seizures that occur in children whilst they’re febrile (only between ages of 6 months and 5 years)
- Fhx
- Socio-economic class
- Winter season
- Zinc/iron deficiency
What are the clinical features of febrile convulsions?
Simple:
- Generalised tonic-clonic seizures
- Last <15 minutes
- Only occur once during febrile illness
Complex:
- Focal seizures
- Last >15 minutes
- Occur multiple times during febrile illness
What is associated with subarachnoid haemorrhages?
Autosomal dominant polycystic kidney disease - berry aneurysms
What are the clinical features of a subarachnoid haemorrhage?
- History of trauma
- Sudden onset
- ‘Thunderclap’ headache
- Loss of consciousness
- N+V
- Confusion
What are the investigations for subarachnoid haemorrhages?
- CT = hyper-attenuation around circle of Willis (‘5 pointed star’ appearance) - suggests aneurysm –> follow with CT angiogram - if more peripheral, suggests due to trauma
- LP = xanthochromia (yellow due to bilirubin breakdown)
What is the management for subarachnoid haemorrhages?
- Immediately stop antiplatelets/anticoagulants
- Endovascular coiling +/- neurosurgical clipping
- IV mannitol for high ICP
What are subdural haemorrhages and what are the risk factors?
Bleeding into subdural space due to ruptured bridging vein
- Anticoagulants
- Accident prone = dementia/elderly/alcoholics/epileptics
- Babies (shaken baby syndrome)
What are the clinical features of a subdural haemorrhage?
- History of trauma
- N+V
- Confusion
- Fluctuating consciousness/drowsiness
- Headache
How can you tell if a bleed in the brain is acute or chronic?
CT:
- Acute - hyperdense (brighter)
- Chronic - hypodense (darker)
What are the investigations for subdural haemorrhages?
CT:
- Haematoma
- Crescent shaped
- Unilateral
- Midline structures shift away
- Cross sutures
What is the management for subdural haemorrhages?
- Immediately stop antiplatelets/anticoagulants
- Clot evacuation to remove haematoma
- Craniotomy
- Burr hole washout
- IV mannitol for high ICP
What are epidural haemorrhages and who are they more common in?
Bleeding into extradural space due to ruptured middle meningeal artery
- Males
- Young people
What are the clinical features of an epidural haemorrhage?
- History of trauma
- Skull fracture
- Lucid interval = initial drowsiness/unconsciousness –> recovery –> rapid deterioration
What are the investigations for epidural haemorrhages?
CT:
- Bi-convex
- Unilateral
- Do not cross sutures
- Midline shift
What is the management for epidural haemorrhages?
- Immediately stop antiplatelets/anticoagulants
- Clot evacuation
- Ligation of bleeding vessel
- IV mannitol for high ICP
What are the clinical features of an intracerebral haemorrhage?
Sudden onset focal neurological symptoms
- Limb/facial weakness
- Dysphasia
- Vision/sensory loss
What are the investigations for intracerebral haemorrhages?
- CT = hyper- attenuation in brain parenchyma, commonly in middle if patient has HTN
- Often associated with subarachnoid haemorrhage as pia is very thin
Which type of stroke is more common?
Ischaemic
What are the risk factors for strokes?
Same as CVD
- Age
- Male
- HTN/hyperlipidaemia
- Diabetes
- Smoking
- Previous TIA
- Heart disease/AF
- COC (ischaemic)
What are the clinical features of a stroke?
- Sudden limb/facial weakness
- Dysphasia
- Visual/sensory loss
- N+V
What are the investigations for haemorrhagic strokes?
- FIRST LINE = CT
- Diffusion-weighted MRI
What is the management for haemorrhagic strokes?
Acute:
- Neurosurgery - evacuate blood
- IV mannitol for high ICP
- Stop anticoagulants
Secondary:
- Anticoagulant
- BP aim of 140/90
- External ventricular drain (if hydrocephalus)
- Rehabilitation (SALT/PT/OT)
What type of infarcts occur in ischaemic strokes?
Cerebral:
- More common
- Occlusion of large blood vessel to cerebrum (e.g. internal carotid artery/middle cerebral artery)
Lacunar:
- Infarcts of smaller blood vessels
- Affected smaller areas e.g. internal capsule/basal ganglia/thalamus/pons
- Produce more specific symptoms
What are the investigations for ischaemic strokes?
- FIRST LINE = Bloods and CT
- Diffusion-weighted MRI
- Carotid USS