BRS Neurology Flashcards
central vs. peripheral hypotonia
central- UMN, altered level of consciousness, increased DTRs, ankle clonus
peripheral- LMN, consciousness not affected, muscle bulk and DTRs are decreased
weak cry, decreased spontaneous movement, frog-leg posture, muscle contractures are signs of ______
hypotonia
when you suspect central hypotonia you should get these tests
head CT
serum electrolytes
genetic study (Down syndrome, Prader-Willi)
when you suspect peripheral hypotonia, get these labs
serum CK
DNA test for spinal muscular atrophy
EMG and nerve conduction studies
muscle biopsy
weak cry, tongue fasciculations, bell shaped chest ,frog-leg posture, normal extraocular movements and normal sensory exam
spinal muscular atrophy- anterior horn cell degeneration (hypotonia, weakness, tongue fasciculations)
classification of SMA
type 1: infantile form, onset < 6 months, aka Werdnig-Hoffman dz
type 2: intermediate form, onset 6-12 months
type 3: juvenile form, onset > 3 years
______ is the second most common inherited neuromuscular disorder after Duchenne muscular dystrophy
SMA
how is SMA inherited and where is the gene
AR
mutation of survival motor neuron gene (SMN1) on chromosome 5
how to dx SMA
DNA testing for abnormal gene is diagnostic in > 90% of cases
muscle bx shows characteristic atrophy of muscles innervated by the degenerating axons
how to tx SMA
what’s the prognosis
supportive care: G tube, monitor for respiratory infections, PT
prognosis: type 1 does not survive past year 1, type 2 survives to adolescence, type 3 survives to adulthood
constipation –> weak cry and suck, loss of previously obtained motor milestones, ophthalmoplegia, hyporeflexia
-paralysis is symmetric and descending
infantile botulism- bulbar weakness and paralysis that develops during year 1 secondary to ingestion of clostridium botulinum spores and absorption of botulinum toxin
what does botulinum toxin do
prevent presynaptic release of ACh
when do sxs of infantile botulism occur in relation to spore ingestion
12-48 hours afterwards
what does EMG show with infantile botulism
incremental response during high-frequency stimulation
how to tx infantile botulism
what’s the prognosis
treatment is supportiv: +/- NG feeding, ventilator
-botulism immune globulin improves clinical course
-do NOT give abx, they might make it worse
prognosis is excellent!
as a neonate
- polyhydramnios
- feeding and respiratory problems as a neonate
- facial diplegia (bilateral weakness), hypotonia, areflexia, arthrogryposis (multiple joint contractures)
- myotonia develops later on
congenital myotonic dystrophy
in an adult, myotonic facies (atrophy of masseter and temporalis muscles), prosis, stiff straight smile, inability to release grip after handshaking
congenital myotonic dystrophy
define myotonia
inability to relax contracted muscle
inheritance of congenital myotonic dystrophy
AD trinucleotide repeat disorder- mostly through the affected mother
chromosome 19
how to dx congenital myotonic dystrophy
DNA testing
how to tx congenital myotonic dystrophy
what’s the prognosis
treatment is supportive
prognosis is guarded… infant mortality can be as high as 40%
all survivors are mentally retarded with average IQ of 50-65
feeding problems subside with time
noncommunicating vs. communicating vs. ex vacuo hydrocephalus
- noncommunicating- enlarged ventricles caused by obstruction of CSF flow
- communicating- enlarged ventricles as a result of increased CSF production or decreased CSF absorption
- ex vacuo- not true hydrocephalus, ventricular enlargement due to brain atrophy
downward displacement of cerebellum and medulla through foramen magnum
what is it and what is it associated with often?
chiari type II malformation
often associated with lumbosacral myelomeningocele
absent or hypoplastic cerebellar vermis and cystic enlargement of the 4th ventricle –> block of CSF flow
Dandy Walker malformation
common cause of hydrocephalus in a premie
intraventricular hemorrhage
signs of hydrocephalus in an infant
bulging fontanelles and split sutures
sunset sign- looks down b/c large 3rd ventricle is pushing on the upward gaze center of the brain
what to do if you suspect hydrocephalus
urgent CT scan
how to tx hydrocephalus and what’s the prognosis
VP shunt
- pts with aqueductal stenosis have the best cognitive outcome
- pts with chiari type II have low-normal intelligence and language d/os
- pts with X linked hydrocephalus have severe MR
any failure of bone fusion in the posterior midline of the vertebral column
spina bifida
herniation of spinal cord tissue and meninges through a bony cleft
myelomeningocele
herniation of the meninges only through a bony cleft
-usually not associated with any neural deficits
meningocele
no herniation of tissue through the vertebral cleft
spina bifida occulta
for spina bifida: ______ is protective
these drugs are teratogenic
folic acid
**depakote, phenytoin, colchicine, vincristine, azathioprine, methotrexate
hairy patch on lumbosacral area… no neuro sxs
SB occulta
fluctuant midline back mass overlying the spine at birth
mass can be transilluminated
meningocele
fluctuant midline back mass mostly in lumbosacral spine
-neurologic defects are present and depend on level of the lesion
myelomeningocele
associated anomalies and complications of myelomeningocele
- hydrocephalus… many cases assoc with chiari II malformation
- cervical hydrosyringomyelia- fluid in central cord canal and in cord itself
- defects in neuronal migration (agenesis of corpus callosum, gyral anomalies)
- orthopedic problems
- GU defects
how to dx spina bifida
elevated AFP in maternal serum- 80% sensitive at 16-18 weeks
fetal US
-if after birth, PE and then xrays for SB occulta, MRI for meningocele
how to manage spina bifida
what’s the prognosis
occulta- nothing –> excellent prognosis
meningocele- surgical repair –> excellent prognosis
myelomeningocele- surgical repair within 24 hours –> most survive to teen years but many are handicapped with neuro deficits
MCC of coma in children < 5 years
nonaccidental trauma
near drowning
MCC come in children > 5 years
drug OD
accidental head injury
coma patient:
flaccidity or no movement suggests damage at ____ or _____
spinal cord or brainstem
decerebrate posturing (extension of arms and legs) indicate _____ injury
subcorticate
decorticate posturing (flexion of arms and extension of legs) sugests _____ injury
b/l cortical injury
hyperventilation in coma suggests ____, ____, or _____
metabolic acidosis
neurogenic pulmonary edema
midbrain injury
cheyne-stroke breathing
what is it and what does it indicate
alternating apneas and hyperpneas
suggests bilateral cortical injury
what is apneustic breathing and what does it indicate
pausing at full inspiration
indicates pontine damage
ataxic or agonal breathing
what is it and what does it indicate
irregular respirations with no particular pattern
indicates medullary injury and impending brain death
unilateral dilated and fixed pupil suggests ______
uncal herniation
bilateral fixed and dilated pupils indicate 3 things
dilating agent
postictal state
irreversible brainstem injury
bilateral constricted reactive pupils suggest _______ or ______
opiate ingestion or pontine injury
if you have an injured ______, you have a negative doll’s eye (oculocephalic maneuver)
brainstem
normal cold caloric results in eye deviation to the ______ (irrigated/nonirrigated side)
abnormal corneal and gag reflexes indicate ____ injury
irrigated
brainstem
what to check in a comatose patient
FSG UDS, electrolytes, metabolic panel head CT urgent EEG \+/- LP to look for meningoencephalitis
epilepsy is _____ or more spontaneous seizures without an obvious precipitating cause
2
______ of children who have a single seizure go on to develop epilepsy
fever than 1/3
most causes of childhood seizures are identifiable (T/F)
F
60-70% of cases, the etiology is unknown
_______ seizures are caused by discharge from a group of neurons in both cerebral hemispheres
what are 2 types
generalized
tonic clonic- has a postictal state
absence- does not have a postictal state
______ seizure are caused by discharge from one hemisphere
what are two types
simple partial- consciousness is not impaired
complex partial- consciousness is decreased
how to dx epilepsy
history and physical
EEG- but this is not required for epilepsy diagnosis
video EEG monitoring- good for little kids, poor historians, sleep epilepsy, etc.
neuroimaging studies should be performed in all children with epilepsy except those with _____ and _____
absence seizures
benign rolandic epilepsy
what to do with a first-time afebrile seizure in an otherwise healthy child with a normal neurologic examination
- doesn’t warrant an investigation
- if they have another one, you should look at serum lytes and neuroimaging
what must you rule out with a febrile seizure
CNS infection
how to tx status epilepticus
IV anticonsulsants (ex. lorazepam or diazepam) followed by a loading dose of either phenobarbital or phenytoin
drug recommendations for treatment of epilepsy
generalized
absence
partial
generalized- depakote or phenobarbital
absence- ethosuximide
partial- carbamazepine or phenytoin
best prognosis for epilepsy surgery is for ______
temporal lobe lesions
other tx for epilepsy (not drugs or surgery)
vagal nerve stimulator- side effect of hoarseness
ketogenic diet- high fat, low carb, produces a state of ketosis
prognosis for epilepsy
not a lifelong disorder many children (70%) can be weaned off meds after 2 years of no seizures
seizure accompanied by a fever owing to a non-CNS cause in pts 6 months to 6 years
febrile seizure
these are fairly common
simple vs. complex febrile seizure
simple- < 15 minutes, generalized
complex- > 15 minutes, focal features, or recurs within 24 hours
dx of febrile seizure
do you need LP, neuroimaging, or EEG?
H&P, normal neuro exam, exclusion of CNS infection
no LP unless you suspect meningitis
no neuro imaging or EEG unless neuro exam is abnormal
management of febrile seizure
first time or occasional- no tx needed
frequent recurrent febrile seizures- daily ppx with depakote or phenobarbitol, abortive tx with rectal diazepam
____% of pts with a febrile seizure will have a recurrence
30%
- brief myoclonic jerks, lasting 1-2 seconds each, occurring in clusters of 5-10 seizures spread over 3-5 minutes
- sudden arm extension or head and trunk flexion (jack-knife seizures or salaam seizures)
infantile spasms (West syndrome)
infantile spasm age of onset
______ is the most commonly identified cause
3-8 months
tuberous sclerosis
EEG: hypsarrhythmia pattern (highly disorganized pattern of high amplitude spike and waves in both cerebral hemispheres)
infantile spasm (West syndrome)
treatment and prognosis of infantile spasm (West syndrome)
what’s first and second line
what’s good for cases caused by tuberous sclerosis
ACTH IM injections for 4-6 weeks
depakote is second line
vigabatrin is most effective if it’s associated with tuberous sclerosis
prognosis is poor: moderate to severe MR despite therapy
absence seizures age of onset and inheritance
5-9 years
AD with age-dependent penetrance
generalized 3-Hz spike and wave discharge on EEG
absence seizure
how to tx absence
what’s the prognosis
ethosuximide (first line), depakote
prognosis is good; usually resolve spontaneously w/o cognitive impairment
nocturnal partial seizure with secondary generalization
- early morning, pts are asleep with oral-buccal manifestations (moaning, grunting, pooling of saliva)
- then generalization into tonic clonic seizures
benign rolandic epilepsy (benign centrotemporal epilepsy)
____ is the most common partial epilepsy during childhood
what age is peak incidence
benign rolandic epilepsy
age 6-7
how is benign rolandic epilepsy inherited
AD with variable penetrance
EEG: biphasic spike and sharp wave disturbance in the mid-temporal and central regions
benign rolandic epilepsy
how to tx benign rolandic epilepsy and prognosis
tx: depakote (first line) and carbamazepine
prognosis is great: usually spontaneous remission with no cognitive defects
_____ are the MCC headaches in children and adolescents
migraines
inheritance and pathophys of migraines
AD inheritance
changes in cerebral blood flow 2/2 release of 5-HT, substance P, and VIP
migraine _____ (with/without) aura is the most common form of migraine in children
without
what is a migraine equivalent
no headache
prolonged transient alteration of behavior that manifests as cyclic vomiting, cyclic abdominal pain, paroxysmal vertigo
headache with unilateral ptosis or cranial nerve III palsy
headache preceded by vertigo, tinnitus, ataxia, or dysarthria
ophthamoplegic migraine
basilar artery migraine
fortifications in migraines
type of visual aura- jagged streaks of light that take on the outline of old forts
migraine tx
abortive
ppx
abortive: sumatriptan (selective 5-HT agonist)
ppx: propranolol
you may find isometric contraction of facial muscles in this type of headache
what don’t you find
tension headache
you don’t find vomiting, visual changes, or paresthesias
how to tx tension HA
ibuprofen, acetaminophen
how to tx cluster HAs
abortive
ppx
abortive: oxygen, sumatriptan
ppx: CCB, depakote
these two types of primary HA are rare in children
tension and cluster
unsteady, wide-based stance with irregular steps and veering
cerebellar gait
_______ is the most common cause of ataxia in children
what’s the age of onset
acute cerebellar ataxia
18 months-7years
common infections that cause acute cerebellar ataxia
varicella, influenza, EBV, mycoplasma
the ataxia occurs 2-3 weeks after infection
mechanism: immune complex deposition in the cerebellum
clinical features of acute cerebellar ataxia
truncal ataxia, deterioration of gait
slurred speech and nystagmus
no fever
how to work up and treat acute cerebellar ataxia
H&P
do head CT to r/o life threatening causes
tx is supportive… usually takes 2-3 months to resolve. PT may be helpful
ascending weakness, areflexia, normal sensation
what is this and what is it most likely caused by?
Guillain-Barré syndrome
campylobacter jejuni, which causes a prodromal gastroenteritis
where is the area of demyelination in GBS
ventral spinal roots and peripheral myelinated nerves
clinical features of GBS
ascending symmetric paralysis
no sensory loss but there may be leg/back pain
cranial nerve involvement (facial weakness in 40-50% of pts)
ophthalmoplegia, ataxia, areflexia
Miller Fisher syndrome (variant of GBS)
dx of GBS- LP, EMP, spinal MRI (when should you do this)
LP: albuminocytologic dissociation (high protein, normal cell count)
EMG: decreased nerve conduction velocity l
spinal MRI: do this in young kids where sensory exam is not reliable, used to r/o spinal compressive lesions
how to manage GBS
what’s the prognosis
IVIG for 2-4 days is the preferred tx in kids
can also do plasmapheresis
complete recovery is the rule in children
- children appear restless- face, hands, arms have continuous, quick, and random movements
- speech can be jerky or indistinct
- chameleon tongue
- choreic hand (flexed at wrist, hyperextended at MCP joint), milkmaid’s sign
- emotional lability
- gait and cognition are not affected
sydenham chorea
- self limited autoimmune disorder associated with rheumatic fever
- occurs 2-7 months after GABHS infection
- cross-reacting antibodies to GABHS and basal ganglia cells
how to dx sydenham chorea
-labs and imaging
elevated ASO or ADB titer (indicates strep infection)
head MRI: increased signal intensity in the caudate and putamen
SPECT: increased perfusion to the thalamus and striatum
how to tx sydenham chorea
prognosis
helperidol, depakote, or phenobarbital
all pts recover within several months to 2 years
tourette’s requires sxs for > _____
also must have have motor and phonic tics before age ______
1 year
18 years
how to tx tourette’s
pimozide, risperidone are effective
clonidine is less effective- can cause sedation
haldol- used to be used but risk of tardive dyskinesia
hypnotherapy
tourette’s prognosis
tics tend to decrease in adulthood
X linked myopathies: _______ and ________
these are due to deletion in the _______ gene
Duchenne and Becker muscular dystrophy
dystrophin
pathophys of DMD and BMD
lack of dystrophin –> weakness and rupture of the plasma membrane –> injury and degeneration of muscle fibers –> infiltration of lymphs into the injured area and replacement of damaged muscle fibers with fibroblasts and lipid deposits
slow progressive weakness affecting the legs
pseudohypertrophy of calves
Gower’s sign
cardiac involvement
DMD or BMD
dx of DMD or BMD
enlarged calf muscles in young boy with muscle weakness
high CK levels
EMG
muscle biopsy
absent or decreased dystrophin levels on Western blot
DNA testing
EMG findings in DMD or BMD
small polyphasic muscle potentials with normal nerve conductions
how to tx DMD or BMD
oral steroids early on can improve strength transiently
prognosis of DMD and BMD
DMD: no walking by age 10 years, most die in late teens from respiratory failure
BMD: no walking by 20s, most survive to 50s
antibodies to AChR at neuromuscular junctions
what are the two types
myasthenia gravis
- neonatal: mother’s antibodies cross the placenta… resolves in a few weeks
- juvenile: AChR antibody formation
- hypotonia, weakness, feeding problems in _______
- bilateral ptosis, increasing weakness later in day, diplopia, DTRs are preserved in _______
- neonatal myasthenia gravis
- juvenile myasthenia gravis
how to dx myasthenia gravis
- tensilon test: IV injection of edrophonium (AChE inhibitor) transiently improves ptosis
- decremental response to repetitive nerve stimulation
- presence of AChR antibody titers
tx of myasthenia gravis, both neonatal and juvenile
nenoatal- symptomatic; if respiration is compromised, give AChE inhibitor or IVIG
juvenile- pyridostigmine is the mainstay (AChE inhibitor), steroids if those don’t work, plasmapheresis during flares, thymectomy
prognosis of myasthenia gravis
neonatal
juvenile
neonatal- resolves in 1-3 weeks
juvenile- remission of sxs occur in 60% after thymectomy
