general neuro Flashcards
ADEM - what’s the problem
AI disease: Type IV hypersensitivity: myelin-specific T cell reaction»_space; inflammation + demyelination of brain and spinal cord
ADEM vs MS
ADEM = single event of demyelination as a child
MS = progressive recurrent bouts of demyelination in young adult
ADEM trigger
trigger unknown - ?protein molecular mimicry.
esp. flu, MMR, human herpes
esp. mycoplasma pneumoniae, beta-haemolytic strep
ADEM - key features
4-8yo
1-3 weeks post infection
systemic inflammation: fever, headache, n/v
POLYsymptomatic of demyelination:
- 80% motor deficits, weakness
- 50% ataxia
- 50% cranial nerves
- optic neuritis usually bilateral
- altered conscious state, seizures
ADEM - MRI and CSF
MRI:
bilateral, multifocal but asymmetric, and large in size
WM abnormalities 90% - subcortical»_space; periventricular
CSF abnormal: pleiocytosis, inc protein, oligoclonal bands in 0-29%
outcomes with ADEM vs ATM
ADEM: 60-90% full recovery
some may have residual deficits
Risk of subsequent diagnosis of multiple sclerosis is low (2-10%)
ATM: 50% normal outcome, 80% normal-good
risk of MS diagnosis also around 10%
main spinal tracts
- corticospinal, descending motor info for voluntary movement
- dorsal column, ascending sensory info (pressure, vibration, fine touch, proprioception)
- spinothalamic, ascending sensory:
- lateral = pain and temp
- anterior = pressure and crude touch
transverse myelitis - key features
- inflammatory demyelination of spinal cord, lesions usually span multiple segments but ‘transverse’ due to sensory impact
- infection/AI trigger
MOTOR, SENSORY AND SPHINCTER DYSFUNCTION:
- bilateral changes: weakness + sensation + pain
- urinary retention common
- UMN signs
UMN vs LMN signs
UMN:
inc muscle tone (due to loss of descending inhibition)
weakness
spastic, rigid paralysis
hyperreflexia, positive Babinski
LMN:
lower tone (due to loss of innervation)
weakness
flaccid paralysis, hypotonia
hyporreflexia
muscle atrophy, fasciculations
Rx for ADEM/ATM
IV methylpred +/- IVIG
most sensitive sequence for ATM/ADEM for MRI
MRI brain + spine w/ gadolinium, axial T2 weighted
optic neuritis - key features
central scotoma
visual acuity loss
lose colour vision - esp red
PAINful
RAPD
a/w infection or vaccination
key causes of optic neuritis
MS
NMO
ADEM
bilateral severe or recurrent optic neuritis - think what?
MOG associated
outcomes for opitc neuritis, and risk for developing MS
recovery up to 2y post - 85%
overall risk MS = 30%
- highest in first 2y, with abnormal MRI, >12, CSF oligoclonal bands
NMO - key features
- recurrent optic neuritis/myelitis
- NMO Abs target aquaporin 4Ab - 91% specific for NMO
- treat with immunosuppressive agents to prevent relapse
NMO vs MS
i. Recovery of visual and spinal cord function is generally not as compete after each episode
ii. ON is more frequently bilateral in NMO than MS
main disease modifying therapy for MS
IFN-beta
CSF of MS vs ADEM
MS = oligoclonal bands
ADEM = pleiocytosis
common organisms causing bacterial meningitis <2mo and >2mo
<2m: GBS, E.Coli, listeria
>2m: strep pneumo, neisseria, Hib
kernig vs brudzinski’s
kernig = hip flexed, knee flexed -> straighten leg»_space; pain at the back of the leg
burdzinski’s: lying spine, then flex neck»_space; involuntary hip/knee flexion
Rx for meningitis
<2mo: benpen + cefotax
>2mo: cefotax/ceftx, can give dexa
normal number of neuts/lymphocytes in CSF
<1mo: 0 neuts, 22 lymph
>1mo: 0 neuts, 5 lymph
most common viral cause of meningitis
enteroviruses e.g. coxackie, polio, echo
most common ways CNS abscesses form
- direct 50% = single abscess e.g. infection, trauma
- haematogenous 50% = multiple abscesses in MCA distribution e.g. pulmonary/cv infections
most common organism for CNS abscess
strep 60%
staph aureus 20%
Rx for CNS abscess
metro + cefotax/ceftx
Mx for stroke and time to do this
alteplase within 4.5h
clot retrieval within 6h
mortality and outcome of childhood stroke
mortality 5-10%
50% long-term neuroimpairment 10-20% suffer recurrent strokes
signs / symptoms more suggestive of haemorrhagic vs ischaemic stroke
Ischaemic:
Focal limb or facial weakness
Visual or speech disturbance
Limb incoordination or ataxia
Haemorrhagic:
Headache with other neurological signs or symptoms
Altered mental state
Signs of raised ICP
imaging modality for haemorrhagic vs ischaemic stroke
haemorrhagic: non con CT +/- CTA
ischaemic: MRI+MRA first, if not then CT+CTA
initial supportive care measures in stroke
avoid hypotension, hypoglycaemia, hypothermia, NBM until safe swallow, IV fluids
most and 2nd most common cause of ischaemic stroke in kids
arteriopathy 50% e.g. moya mya
cardiac disease 25%
others haematological e.g. prothrombotic / sickle cell
most common territory affected for ischaemic stroke
MCA
exam q: drug causing cerebral sinovenous thrombosis
l-asparaginase
symptoms of mca stroke
contralat weakness face/arm
contralat homonymous hemianopia
contralat sensory loss
global aphasia
what is todd paralysis
brief paralysis post seizure
what is PRES
hypertensive encephalopathy - seizures, confusion vision loss
positive movement disorders: athetosis vs dystonia vs chorea/myoclonus vs tics
-athetosis = slow, writhing, non-rhythmic. worse with movement.
-dystonia = sustained, non-rhythmic, worse with movement
-chorea (distal muscles), myoclonus (multiple groups) = rapid, nonsuppressible
- tics = rapid, suppressible
chorea makes you think of what disorders
- RF (sydenham’s)
- huntington’s
- thyroid
- lupus
NMS vs serotonin syndrome
both hot and autonomic problems
serotonin syndrome
- 24h onset, 24h resolution
- hyperreflexia, tremor, myoclonus
- treat: with benzo
NMS
- days to weaks onset and resolution
- hyporeflexia, rigidity
- treat: bromocriptine
wilson’s disease = what kind of movement disorder
dystonia
types of tremor
- static (PD)
- postural (thyroid / physiological)
- intention (cerebellar e.g. Wilson’s)
key features of essential tremor in kids
- not at rest, mostly at end of activity
- hands/forearms
- FHx
- respods to alcohol
tourette - key features
onset before 7y
multiple motor and vocal tics, nearly every day
a/w ADHD
lesch-nyan key features
X linked disorder of purine breakdown, leading to excessive uric acid – choreathetosis, spasticity, chorea, biting and aggressive behaviours
key features - acute cerebellar ataxia
Dx of exclusion
1-3yo, resolves in 2-3 weeks
2-3 weeks post viral
sudden onset truncal ataxia, vomiting, speech problems, cerebellar signs
most common degenerative vs hereditary ataxia
degenerative: ataxia telangectasia
hereditary: friedreich’s
key features of friedreich’s ataxia
- Triple GAA repeat in gene encoding for the mitochondrial protein frataxin > oxidative injury
- 10y onset
- ataxia lower > upper
- dysarthria
main drugs causing IIH
tetracyclines, doxycycline, nitrofurantoin, isotretinoin
main Rx for IIH
acetazolamide
key features of acute necrotising encephalopathy
- triggered by virus - HH6/lnfluenza
- high LFTs without NH3 rise
- mostly Asian
red flags for headaches
Progressive chronic headaches
Focal neurological symptoms
under 6 yrs
Headache/vomiting that wakes child or present on waking (symptoms of raised intracranial pressure (ICP))
Consistent location of recurrent headaches
VP shunt
Known systemic disorder
primary headache types
TTH: bilat, pressing, chronic non-progressive, stress, hours to days
migraine: uni/bilat, PULSATILE, acute recurrent, worse with activity, aura, NV, photophobia
cluster: unilat, around eye, autonomic Sx
most common migraine aura in kids
photopsia - flashes and floaters
Rx for headaches
acute:
NSAID
sumatriptan >12y
chlorpromazine
prophylactic:
beta blocker (think of CI)
cyproheptadine
amitryptilline
CSF and MRI in AI encephalitis
CSF - pleiocytosis, inc protein
MRI - non-diagnostic
Rx for encephalitis
IVIG + methylpred
after 10 days if no response. >ritux
pathologenesis of anti-NMDA encephalitis
- IgG Ab to NR1 subunit of NMDA-rec > GABAergic pathways don’t work
epidemiology of anti-NMDA encephalitis
- females
- most common AI encephalitis
clinical presentation key features of anti-NMDA encephalitis
- prodrome in 50%
- early phase: psych stuff, movement disorder, sleep disturbance, seizure
- late phase: echolalia, autonomic, breathing badness
- 40% females have ovarian teratoma
outcome for anti-NMDA encephalitis
full recovery in 80% but up to 2years, very slow recovery
releapse in 20%
what is opsoclonus
uncontrolled, irregular, and nonrhythmic eye movement without intersaccadic intervals
cerebellar encephalitides /opsoclonus-myoclonus = think WHAT for exams
50% have neuroblastoma bruh
rasmussen encephalitis - key features
only one hemisphere affected - functional hemispherectomy required
progressive refractory seizures
the two abx we care about for AI encephalitis
anti-NMDA
anti-VGKC
opsoclonus-myoclonus syndrome - key features
opsoclonus
myoclonus
ataxia - often misdiagnosed with acute cerebellar ataxia of childhood
CD20 B cells in CSF
paraneoplastic - esp neuroblastoma
