neurology Flashcards
What investigations should you complete a neonate with seizures of unknown cause
glucose/calcium/Mg/U&Es and acid/base status FBC and film CSF analysis blood, urine and CSF cultures cranial US
What additional investigations may you consider once the standard seizure investigations are done
ammonia lactate uric acid liver enzymes biotinidase levels blood and urine amino acids Torch screen MRI brain EEG genetic testing
What are the most common bacterial causes of meningitis in neonates
group B streptococcus
E. Coli
Listeria monocytogenes
What is the most common cause of neonatal encephalitis
vertical transmission of herpes simplex virus
How would you diagnose bacterial meningitis on CSF
isolation of the bacterium
increased WCC
Raised protein
decreased glucose
What does an infantile seizure (west syndrome) present as
sudden, tonic clonic contractions lasting 5-10 seconds with spasms often occurring in quick succession
When does West syndrome usually occur
4-8 months
How does West syndrome present
infantile spasms, often when child is waking up
Who is at risk of developing West syndrome
- previous brain injury <6 months
- brain malformation
- genetic abnormalities
What is the management of West syndrome (infantile spasm)
- prednisilone or vibigatran
- the other of the above
- pyroxidine
- AEDs
What type of spasms do you see in West syndrome
Both extensor and flexor spasms
- Extensor: extend neck and trunk and abduct limbs
- flexor - ‘self hugging’
What would you see on EEG in West Syndrome (infantile spasms)
Hypsarrythmia - chaotic high to very high voltage polymorphic EEG
What are the common causes of seizures in neonates
- hypoxic ischaemic
- encephalopathy
- intracranial haemorrhage
- intracranial infections
- congenital cerebral malformations
- metabolic disorders
What investigations should you do if you feel there is an underlying metabolic disorder causing seizures
glucose electrolyte magnesium calcium metabolic screen (urine and plasma)
What is the most common cause of seizures in a term infant
hypoxic ischaemic encephalopathy
Usually occurs in the first 24-48 hours of life
What is the most common cause of seizures in a pre-term infant
intra-cranial haemorrhage - Cranial US
What are the differential diagnoses of seizures in a neonate
jitteriness + benign neonatal sleep myoclonus
How can you tell between true epileptiform movements and non-epileptiform
stopped by gentle restraint and can be reproduced by sensory stimuli
What is Benign neonatal sleep myoclonus
- bilateral or localised myoclonic jerks only in sleep,
- consistent cessation with arousal
- Normal EEG
- normal neurological examination,
- good outcome
Feautires of jitteriness
movements are stimuli sensitive
movements stop with gentle constraint
predominantly a tremor as opposed to tonic clonic
No CVS changes or eye movements
Feautires of jitteriness
movements are stimuli sensitive
movements stop with gentle constraint
predominantly a tremor as opposed to tonic clonic
No CVS changes or eye movements
Most common presentation of tuberous sclerosis
epilepsy (infantile spasms)
- autism
- cognitive impairment
- neonatal cardiac rhabdomyomas
What is tuberous scelerosis
autosomal-dominant, neurocutaneous, multi-system disorder characterised by cellular hyperplasia, tissue dysplasia, and multiple organ hamartomas
What is a reflex anoxic seizure (reflex asystolic syncope)
Occurs from early infancy and onwards
unpleasant, sudden stimulus leads to a profound vagal discharge resulting in a fast drop in HR and transient asystole.
WHat skin lesions may you see in tuberous sclerosis
cafe au lait spots shagreen patches hypo-pigmented as leaf patches adenoma sebacum - acne like rash subungal/periungal fibromatoma
What are the most common CNS lesions in tuberous sclerosis
cortical tumours
subependymal nodules
What neuroimaging is reocmmended in patients with tuberous sclerorsis
MRI every 1-3 years until the age of 25
What is Landau Kleffner Syndrome
subacute onsent of aphasia and seizure activity (usually focal) with abnormal EEG
Usually between 3-7
treated as an epileptic disorder
How do benzodiazepines terminate seizures
They enhance the effect of GABA on GABA receptors leading to neural inhibition
Why is buccal medicine accepted to terminate a seizure
avoids first pass hepatic metabolism
How do you caclultate the dose of benzodiazepines as a rescue med
by age
Age 5-9 is 7.5mg
What advice should be given to parents about seizures
- wait 5 mins before rescue meds
- 999 if not slowed/stopped in 5 mins
- 999 if unable to give meds
- 999 it stops breathing/difficulty breathing
- ONLY give ONE dose at home
What is the AED of Choice for absence seizures
ethosuximide or sodium valproate (boy only)
What is the AED of Choice for focal seizures
carbamazepine or lamotrigine
What is the AED of Choice for generalised tonic clonic
sodium valproate
Lamotrogine if sodium valproate inappropriate
What is the AED of Choice for myoclonic seizures
- sodium valrpoate
- levetiracetam or topiramate
What is Dravets syndrome
- severe prolonged seizures triggered by high body temp
- drug resistant
- start in first year of life
- associated with learning difficulties etc and autism
What is the management of Dravets syndrome
toperimate/sodium valproate
Diagnosis criteria of Lennox-Gasteau
- multiple generalized seizure types
- a slow spike-and-wave pattern (less than 2.5 Hz) on EEG
- cognitive dysfunction
How does juvenile myoclonic epilepsy present
- sudden brief bilateral jerks in morning. conciousness unimpaired
- few years later generalised tonic clonic seizure
what is the management of juvenile myoclonic epilepsy
lamotrigine
valproate
Benign epilepsy of childhood with centrotemporal spikes
- brief, simple partial and hemifacial motor seizures with somatosensory symptoms
- often evolve into tonic clonic
complex partial seizures
absences, lip smacking and repetitive movements
Causes of raised ICP
- traumatic brain injury
- hydrocephalus
- brain tumours
- intracranial infections
- hepatic encephalopathy
- impaired CNS outflow
Causes of cerebral oedema
- Head trauma
- tumour
- hydrocephallus
- hypoxic/ischaemix encephalopathy
- infectious
- DKA
- stroke
- venous thrombosis
- AV malformations
- vasculitis
Features of acutely raised ICP
- headache
- vomiting
- altered mental state
- papilloedema
- HTN with brady/tachycardia
- seizures
Features of chronically elevated ICP
- Headache
- vomiting
- Parinaud syndrome - abnormalities with vertical gaze
- Visual changes
- papiloedema
- neurology e.g ataxia
What is the initial investigations of choice if ? raised ICP
CT without contrast
MRI
What features on CT suggest raised ICP
- midline shift
- effacement of basilar cisterns
- effacement of the sulci
- Thumb printing - increase gyral marking on inner table of the skull.
Key features of medulloblastoma
headaches early morning vomiting unsteadiness 6th nerve palsy (posterior fossa tumour)
Key features of neurofibromatosis 1
C - cafe au lait spot >5 A - axillary freckling F - fibromas (2 or more) E - Eye - lisch nodules S - skeletal anomalies P - Positive FH OT - Optic tumour - gliomas (learning difficulties)
What skeletal anomalies may you seen in neurofibromatosis
leg bowing
sphenoid dysplasia
What is neurofibromatosis 1
- genetic condition causing benign tumours to grow along nerves
- usually presents by age 1
Where is chromosomal anomaly in neurofibromatosis 1
NF1 on Cr 17
How does neurosarcoidosis present
rash
uveitis
arithitis
neuro involvement is rare in children
What is the management of Benign epilepsy of childhood with centrotemporal spikes
- No AED
- If frequent seizures - carbmazepine or lamotrigine
- until 14-16yrs or 2 years seizure free
First line agent in neonatal seizures
phenobarbitone
Features of WIlson’s disease
Jaundice tremor dysphagia dysarthria poor co-ordination lethargy (anaemia 2ry to liver dysfunction) easy bruising Kaiser Fleisher rings (copper rings) psychiatric manifestations menstrual irregularities
Management of Wilsons’
chelating agents - penacillamine, zine trientine
WHat is neuroancyanthosis
- group of conditions with mishapen spiny red blood cells + neurological anomalies.
Features of neuroancyanthosis
chorea
can begin of childhood to adulthood and can progress and different speeds
