Neuro (NEW) Flashcards
1
Q
Meningitis background
A
Epidemiology
- bacterial
- > peak in neonates and elderly
- > high rate in children
- viral
- > more common than bacterial
Aetiology
- bacterial
- > s. pneumoniae (most common/decreasing incidence)
- > h. influenza b (decreasing influence)
- > n. meningiditis (any age)
- > l. monocytogenes (neonates/old/immunocomp/alcohol)
- > GBS (neonates)
- > e. coli (neonates)
- > gram negative rods (skull fracture/neurosurgery)
- viral
- > enterovirus (most common)
- > HSV 1 and 2
- > varicella zoster
- > west nile
- > HIV
Pathophys
- haematogenous spread most common
- microbe enters subarachnoid space and proliferates
- inflammation
- > increased permeability of BBB and influx inflamm cells
- > oedema and raised ICP
2
Q
Meningitis clinical manifestations
A
Hx
- Presenting complaint
- > acute or gradual onset
- > headache
- > neck stiffness
- > photophobia
- > fever
- > altered mental status
- > seizures
- > vomiting
- Neonate
- > any non specific sign of infection
- > jaundice
- > hypothermia
- > apnoea
- > bulging fontanelle
- Elderly
- > altered mental status
- Viral screen
- > sore throat (enterovirus)
- > sores around mouth/genitals (herpes)
- > shingles (varicella)
- Exposures
- > antecedent illness
- > trauma or infection around head
- > sick contacts
- > immunosuppression (corticosteroids, alcohol)
- > travel
- > animal/insect bites
- Vaccination hx
Exam
- vitals
- > sepsis/shock
- > cushings triad
- assess level of consciousness/confusion
- rash
- > petechial/purpuric (meningococcal/enterovirus)
- > maculopapular (early meningococcal/enterovirus)
- meningism
- > nuchal rigidity (resistance to passive neck flexion)
- > kerning’s (resists straitening flexed knee w. hips flexed)
- > brudzinskis (neck flexion causes knee/hip flexion)
- papilloedema/bulging fontanels
- > raised ICP
- focal signs
- > CN III, IV, VI palsies (eye movements)
- > facial palsies
- > hemi/quadriparesis
- source of infection
- > sinusitis
- > mastoiditis
- > otitis media
- > pneumonia
3
Q
Investigations meningitis
A
Consider CT before LP if signs of raised ICP
-oedema and hydrocephalus common in meningitis
Lumbar puncture
- opening pressure raised
- cell count and differential
- > higher WCC in bacterial
- > pleocytosis bacterial
- > mononuclear cells classically in viral (not always)
- protein
- > raised in bacterial/normal or raised in viral
- glucose
- > low in bacterial (CSF:serum glucose <0.4)
- > may be low in viral (CSF:serum glucose >0.5)
- lactate
- > high in bacterial
- > helps rapidly distinguish aseptic from bacterial
- gram stain
- > much faster than culture
- > sensitivity varies by etiological organism
- culture
- > high sensitivity but low after antibiotics
- PCR multiplex for viral and bacterial pathogens
- > rapid
- > highly sensitive and specific
- latex agglutination for n. meningitis capsular antigen
- > rapid results
- > little utility
FBC -leukocytosis -DIC (anaemia and thrombocytopaenia) Metabolic panel (glucose, electrolytes, CMP) -all may be low CRP -normal excludes bacterial when gram stain negative Coags -evidence of DIC Blood culture -may be positive in bacterial Consider procalcitonin ->sensitive and specific for bacterial
4
Q
Meningitis treatment
A
Bacterial
- neonate <2mths
- > benzylpenicilin 60mg/kg IV
- > cefotaxime/ceftriaxone 50mg/kg IV
- > no steroids
- adults and child >2mnths
- > cefotaxime/ceftriaxone 2g (child 50mg/kg) IV
- > dexamethasone 10mg (0.15mg/kg) IV before antibiotics
- notifiable disease and contact tracing/prophylaxis
- > h. influenza
- > s. pnuemoniae
- > n. meningiditis
- audiology follow up 2 months post discharge
- monitor neurodevelopment
Viral
- treat with antibiotics and steroids until confirmed
- supportive care
- > hydration
- > analgesia
- > antipyretics
- > anti-emetics
- aciclovir if
- > HSV
- > varicella
5
Q
Reversible cerebral vasoconstriction syndrome overview
A
Epidemiology
- can occur at any age
- > most common in middle age
- much more common in women
Aetiology
- unknown
- majority
- > post partum
- > post adrenergic/serotinergic drug
Pathophys
- reversible cerebral artery narrowing
- outcome
- > parenchymal oedema
- > stroke
- > convexal SAH
Clinical manifestations
- thunderclap headache
- > last for a few hours
- > recurrence is common shortly after
- > long term recurrence is rare
- following trigger
- > exertion
- > emotions
- > sex
- nausea
- photosensitivity
- HTN
- seizure/stroke symptoms may occur
Investigations
- MRI
- > often normal
- > parenchymal oedema/haemorrhage
- > convexal SAH
- > bilateral watershed infarcts
- MRA
- > sausage on a string arteries
- consider
- > LP as thunderclap work up
- > FBC/EUCs/ESR for differentials
Management
- supportive
- > analgesia
- > BP
- > seizures
- > stroke
- disease recurrence is unusual
- > avoid triggers for several weeks
6
Q
Spontaneous intracerebral haemorrhage background
A
Epidemiology
- approx 15% strokes
- incidence increases with age
- risk factors
- > HTN
- > anticoagulation/antiplatelets (mainly warfarin)
- > high alcohol intake
Aetiology
- Hypertensive vasculopathy (most common)
- Cerebral amyloid antipathy (older adults)
- AV malformation (children)
Pathophys
- Penetrating arteries exposed to pressure of parents
- > basilar penetrators (pons/mid brain)
- > thalamostriate off PCA (thalamus)
- > lenticulostriate off MCA (putamen/caudate)
- > cerebellar
- Expanding clot and perilesional oedema
- > rising ICP/decreased perfusion/ischaemia/herniation
7
Q
Spontaneous intracerebral haemorrhage findings and specific management
A
General presentation
- may occur due to trigger or spontaneous
- signs and symptoms progress gradually
- headache
- vomiting
- meningism if intraventricular blood
- altered mental status/LOC (late sign)
- occasionally
- > seizures
- > arrhythmias and trops
Syndromes
- putamen (most common)
- > hemiplegia/hemisensory loss
- > homonymous hemianopia
- > gaze palsy
- internal capsule
- > dysarthria
- > hemiplegia/hemisensory loss
- thalamus
- > hemiparesis/hemisensory loss
- > upward gaze palsy with fixed miosis
- > inward peering or preference to ipsilateral
- pontine
- > coma (RAS)/paraylysis/miosis
CT non con ->ischaemic vs haemorrhagic stroke ->midline shift ->estimate haemorrhage volume ->subarachnoid expansion ->predict haemorrhage expansion CT agnio -underlying aetiology ->aneurysms/vascular malformation? ->micro bleed location (amyloid vs HTN) -predict haemorrhage expansion (spot sign)
Specific management
- BP
- > treat if hypertensive
- > aggressive treatment favoured if SBP>220
- ICP
- > maintain head at 45 degrees
- > mild sedation
- > consider monitoring/mannitol/CSF drainage
- Anticoag/antiplatelet ceased and reversal
- > warfarin = FFP + vitamin K
- > UFH = protamine
- > aspirin = desmopressin
- Surgery
- > haematoma excavation for cerebellar or hydrocephalus
- > craniotomy for supratentorial bleed is controversial
8
Q
Aneurysmal SAH evaluation
A
Hx
- thunderclap headache following trigger
- > exercise
- > emotions
- > sex
- vomiting/LOC/nuchal rigidity
- may develop seizure
- may report sentinel bleed
- risk factors
- > family hx
- > smoking/heavy alcohol
- > HTN
- > polycystic kidney disease/connective tissue disease
- > simpathomimetics/anti-coags/anti-platelets
Exam
- altered level of consciousness
- HTN
- meningism
- eyes
- > tersons
- > papilloedema
- > CN III/VI palsy
- neurological signs
- > nearly any
Investigations
- CT non con
- > SAH
- follow with CT angio or DSA
- LP if negative CT
- > high opening pressure
- > RBC count maintained across viles
- > xanthochromia
- ECG and troponins
- > cardiac complications
- FBC
- > anaemia?
- > thrombocytosis?
- Coags
- EUCs
- > hyponatraemia
9
Q
ddx and symptomatic causes seizures
A
Some Crazy People Try To Mimic Real Seizure Movements
- syncope
- cardiac arrhythmia with syncope
- psychological
- > psychogenic
- > panic attack
- TIA
- Transiant global amnesia
- Migraine with aura
- Rigors
- Sleep disorder
- > narcolepsy
- > cataplexy
- Movement disorder
- > tics
- > tremor
- > chorea
SHITTEDD
- stroke
- haematoma/haemorrhage
- > epidural/subdural
- > subarachnoid
- infection
- > meningitis/encephalitis
- > abscess
- TBI
- tumour
- encephalopathy
- drugs and alcohol
- degenerative
10
Q
ddx dizziness
A
Vertigo
- Big 3
- > BPPV
- > vestibular neuritis
- > cerebellar stroke/posterior circulation ischaemia
- Peripheral
- > Menieres
- > labyrinthine concussion
- Central
- > vestibular migraine
- > acoustic neuroma/posterior fossa tumours
- > MS
Syncope/presyncope (TROPICS)
- TIA
- Reflex vasovagal
- Orthostatic hypotension
- Panic
- Intoxication/ingestion
- Cardiac
- Seizure
Balance (PIES)
- Peripheral neuropathy
- Injury
- Eyes
- Spinal pathology
- > spondylosis
- > cord compression
11
Q
DDX bilateral lower limb weakness
A
Head -stroke Spinal -FAINT Nerves -peripheral neuropathy Muscles -MG -alcoholic myopathy -myositis Systemic illness -infections -anemia -hypothyroid -electrolyte abnormality -heart disease Meds -beta blockers/chemo/opioids
Spinal cord compression (FAINT)
- Fractured vertebrae
- > osteoporosis
- > steroids
- > tumour infiltration
- Abscess
- Intervertebral disc
- > discitis
- > herniation
- Neoplasia
- > primary (meningioma)
- > secondary (breast/lung/kidney/prostate)
- Trauma
