neuro diseases Flashcards
7 signs and symp of Freidreich Ataxia
1) progressive ataxia
2) Severe dysarthia
3) loss of position sense
4) impaired vibratory sensation
5) loss of tendon reflexes (with extensor plantar responses)
6) pt usually in a wheelchair by age 5
7) spasticity
what is the nucleotide repeat in freiderich ataxia?
GAA
two major differences between Huntington’s disease and Freidreich Ataxia
- Freidreich ataxia is autosomal RECESSIVE (huntington’s disease is dominant)
- Freidrich ataxia presents in childhood (usually in a wheelchair by age 5) (Huntington’s ave age = 40 yo)
7 yo boy w/ worsening uncoordinate arm and leg mvmt, slurred speech, no family HO neuro/muskuloskeleton disorders, preserved language but gross dysarthria, staggering gait, limited ability to walk unassisted, normal bulk and tone, but strength diminished, patellar and ankle reflexes are absent, vibratin and position sense is impaired. What disease is it and how is it transmitted?
Freidreich ataxia– autosomal RECESSIVE- GAA trinucleotide repeat
what chronic, slowly progressive, multisystem disease characterized by muscle wasting is associated with cataracts and heart conduction deficits?
myotonic dystrophy
An autoimmune disorder resulting in progressive weakness that ascends from the lower extremities, usually after a viral ifxn or other medical condition (like systemic lupus erythematosus and hodgkin disease)
Guillain Barre syndrome
In 98% of the cases, Freidreich ataxia results from a GAA trinucleotide repeat in which gene?
frataxin gene
inflammation localized to a small portion of the spinal cord (lateral corticospinal tracts) or cerebral cortex (precentral gyrus) may occur in…
progressive multifocal leukoencephalopathy (PML) or MS
PML occurs in people who are…
immunosuppresed
classic autoimmune disease involving the NMJ is…
myasthenia gravis- but this mainly affects extraoccular muscles and isolated limb weakness is rare
the MCA provides blood to…
primary motor cortices on lateral aspects of hemispheres —> brainstem (innervating face), spinal cord innervating upper limbs, trunk and proximal part of lower extrem)
The PCA sends blood to…
the occipital cortex
interruption to the PCA would cause
visual deficits rather than paralysis
50 yr old woman w/5 yr HO headaches, generalized tonic-clonic seizures, bilat. leg weakness, skull hyperostosis of calvarium, intracranial mass. microscopic exam shows whorling pattern of cells- most likely diag?
meningioma
meningioma- what are they? what are they made of? what do they look like histologically?
slow growing, benign tumors- 15% of IC (intracranial) tumors, common in elderly. Originate from dura or arachnoid, sharply demarcated from brain tiss. cause an osteoblastic rxn in overlying cranial bones. cells have a tendency to circle one another —> form whorls of psammoma bodies.
how do meningiomas present?
as mass lesions, seizures may occur, produce leg weakness
txt of meningioma?
usually surgical
where do arachnoid cysts usually occur?
sylvian fissure
what is a glioblastoma multiforme?
an aggressive malignant astrocytoma —> would kill pt relatively quickly
oligodendrogliomas
glial tumors that could produce symptoms sim to meningioma (seizures may occur, produce leg weakness) but no hyperostosis or whorling pattern microscopically
microscopically, meningiomas are unique in that they…
form whorls of psammoma bodies
Type I arnold Chiari clinical manifestations- when would they start and what are they?
might start in adolescence or adult life, may include cerebellar ataxia, obstructive hydrocephalus, brain stem compression and syringomyelia
Type II arnold-chiari clinical manifestation- when do they present/what are they?
present in childhood (15% die within 1 year)
- difficulty swallowing (compressed nucleus ambiguus)
- loss of Pain/Temp sensation on back of neck/shoulders (syringomyelia) which interrupts the ascending afferent sensory fibers in spinothalamic tracts
- mental retardation secondary to coincident meningomyelocele
- hydrocephalus due to occlusion of CSF flow thru foramen magnum
Dandy WalkerSyndrome brain features
- cerebellar vermis hypoplasia
- dilation of the 4th ventricle (foramina of Lushka and Magendie don’t open!)
symptoms of Dandy-Walker syndrome
- hydrocephalus (no foramina of luschka or magendie so dilated 4th ventricle)
- ataxia- hypoplasia of vermis
- mental retardation
“Dandy Walker has trouble Walking!”
relative prevalence of arnold-chiari vs Dandy-Walker
arnold chiari = relatively common (esp type I): 1/100
Dandy-Walker: relatively uncommon: 1/25000
hydrocephalus
too much CSF in ventricles
- mt lead to Increased ICP (if brain tissue = compressed/can’t recover —> mt lead to mental retardation)
most common congenital cause of hydrocephalus? What causes that?
aquaductal stenosis (usually caused by maternal ifxn with cytomegalovirus (CMV) or toxoplasmosis)
maternal ifx with cytomegalovirus (CMV) or toxoplasmosis can cause what in the baby?
congenital aquaductal stenosis in the baby —-> hydrocephalus
presentation of hydrocephalus
thinning of skull bones and cerebral cortex
cranial sutures don’t close until several yrs after birth, and ICP pushes bones apart —> bigger head
txt for hydrocephaly
- extraventricular shunt (from ventricle to peritoneum)
- endoscopic 3rd ventriculostomy (opening blockage)
- cauterization of ependymal cells– reduce CSF production
microcephally - what is it and what happens to head size? clinical manifestation?
small brain size —> small head size bc brain growth —> skull growth
- 50%: mental retardation
microcephaly mt be caused by…
- genetic causes
- prenatal ifxn
- teratogen exposure (ETOH, toxoplasmosis, radiation)
what is holoprosencephaly
midline of forebrain doesn’t cleave– forbrain might lack midline features like the corpus callosum, and might just have 1 ventricle in the middle of brain instead of bilat. vent.
when is holoprosencephaly (when the midline of the forebrain doesn’t cleave) seen?
fetal ETOH syndrome and Patau syndrome (trisomy 13)
clinical presentation of holoprosencephaly? Prognosis?
Presentation: mild (only 1 excisor?) - severe (cycloplegia- lack of central midline structures and a single ventricle)
- degree of mental retardation depends on severity of disease
prognosis:
mild: normal life
severe: mental retardation/early death
most common cause of mental retardation?
fetal ETOH syndrome
fetal ETOH syndrom, the most common cause of mental retardation, is charaterized by (4):
- microcephaly
- congenital heart disease
- abnormal facies and, in severe cases,
- holoprosencephaly
Patau syndrome (trisomy 13) is characterized by (7):
holoprosencephaly microcephaly polydactyly cleft palate narrow fingernails apneic spells death within 1 yr
epidural hemorrhage usually due to? which artery?
blunt trauma
middle meningeal artery
imaging of epidural hemorrhage shows…
biconvex lens bordered by suture
subdural hemorrhage usually due to?
deceleration injury —> rupture of bridging veins
subdural hematoma presentation?
decline in mental status over days to weeks (venous bleeding from bridging veins accumulates slowly)
imaging of subdural hematoma
crescent shape area that does NOT cross midline but does cross the dural attachments (suture lines) (unlike epidural hemorrhage)
sundural hemorrhages are seen most often in…
elderly (cortical atrophy —> increase P on bridging veins), alcoholics and shaken babies
Subaracnoid hemorrhage (SAH) usually due to…
ruptured berry aneurism in circle of willis
presentation of SAH (sub arach hem.)?
sudden onset, worst headache of my life
risk factors for SAH (sub arach hem) (6)
HTN, smoking, autosomal dominant polycystic kidney disease (ADPKD), Marfans, Ehlers-Danlos Type 4, old age
“talk and die syndrome”
a lucid interval in 50% of pt with epidural hematoma
Intracerebral/parenchymal hemorrhage usually caused by:
tramua, infact, amyloid angiopathy (alzheimers), diabetes, HTN (charcot-bouchard aneurysm)
most intracerebral.parenchymal bleeds localize to…
basal ganglia or thalamus
bacterial meningitis characterized by:
high fever
headache
nuchal rigidity
kernig and brudzinski sign
viral meningitis (aseptic meningitis) presentation:
similar to bacterial but less acute/less severe
fungal meningitis is often seen in
immunocompromized pt, often due to cryptococcus
fungal meningitis is often caused by _____
cryptococcus
daignosis of meningitis is made by…
LP (lumbar puncture)
kernig sign
Pain elicited while straigtening knee with hip flexed at 90 degrees
- done for suspectedmeningitis
** meningismal sign that manifests when inflamed meninges = stretched
Brudinski sign
pt flexes knees in response to passive flexion of the neck
- done for suspectedmeningitis
** meningismal sign that manifests when inflamed meninges = stretched
In a lumbar puncture, the needle encounters what 9 layers?
- skin
- sub q
- Supraspinous/interspinous ligaments
- ligamentum flavum
- epidural fat
- epidural space
- dura mater
- arachnoid mater
- subarachnoid space
meningioma- what is it?
more common in males or females?
how do they present?
what do you do about them?
- benign, well-circumscribed, slow-growing tumor, significant for whorling pattern of cells
- females
- headache or sudden paralysis
- resection or, rarely, radiation
what is a common site for metastatic spread from cancer outside the CNS into the CNS? what is it called when this happens?
the meningeal space
- called carcinomatous meningitis
carcinomatous meningitis- what is it? what is prognosis? what is presentation? txt?
metastatic spread of cancer outside the CNS into the meningeal space– life threatening
presentation: mental status changes and headaches. CN deficits
txt: chemo delivered to CSF (intrathecal)
intrathecal
delivered to CSF
61 yo man brought to physician bc of confusion/difficulty walking. 35 yr HO ETOH abuse, but not drinking currently. ataxia and sluggish pupillary light reflex. At one wk follow-up, normal gait and pupillary light reflex. Severe short-term memory impairment and frank confabulation. What is the disease? what is the vitamin deficiency?
Wernicke-Korsakoff syndrome, caused by thiamine (vit B1) deficiency (usually secondary to chronic ETOH abuse)
Wernicke-korsakoff syndrom
- cause
- acute symp (7)
- chronic symp (2)
cause: thiamine (vit b1) deficiency (usually secondary to chronic ETOH abuse)
acute: confusion, ataxia, vestibular dysfunction, sluggish pupillary light reflexes, anisocoria, and occulomotor dysfunction
chronic: anterograde amnesio and confabulation in an alert and responsive pt
Thiamine (B1) deficiency is associated with what three things?
- Wernicke-Korsakoff syndrome (usually secondary to chronic ETOH use)
- polyneuritis (“dry” beriberi) (inflammation of several peripheral nerves simultaneously.)
- cardiomyopathy (“wet” beriberi)- dilated, high-output cardiomyopathy- looks like CHF
dermatitis is associated with what three vitamin deficiencies?
- pantothenic acid
- biotin
- pellagra or niacin deficiency
diarrhea, dermatitis and dementia are the triad of symp for what deficiency?
pellagra or niacin deficiency
thiemine deficiency leads to what type of cardiac failure?
high output, or dilated cardiomyopathy (rather than hypertrophic cardiomyopathy)
megaloblastic anemia results from what deficiency?
vitamin B12/folic acid deficiency
night blindness is most strongly associated with what deficiency? why?
Vit A bc a derivative (retinal) functions as a constituent of the light receptor rhodopsin in the rod cells which are responsible for night vision bc of their sensitivity to low light.
Wernicke syndrome is the triad of…
nystagmus, opthalmoplegia and ataxia (along with confusion)
if Wernicke syndrome progresses to Korsakoff syndrome, what other symptoms appear?
impaired anterograde memory and confabulation (bc mammalary bodies are affected)
prosopagnosia
inability to recognize faces- usually caused by bilateral lesion of the visual association cortex
agnosia
normal perception, but the perception is devoid of meaning (ie prosopagnosia = inability to recognize faces)
alexia
impairment in reading cause by deficits in central language processing. It can occur in isolation or in conjunction with agraphia (impaired writing)
anosognosia- what? what causes it?
deficit in cognition about one’s illness, or the lack of awareness that one is suffering from a certain condition. It is related to large lesions of the non-dominant parietal lobe which causes the pt to be confused/unaware of motor/sensory deficits.
asomatognosia
lack of knowledge about one’s own body. for example, hemiasomatognosia can occur with hemineglect, and pt will deny that half of their body actually belongs to them
confabulation
fabrication of stories and events that never happened in order to fill in memory gaps. seen mostly in dementias
ganser syndrome- what? association w/what other symp? most commonly seen in…
dissociative disorders not otherwise specified- giving approximate answers instead of exact ones. Assoc. with symp such as amnesia, disorientation and perceptual disturbances. Most commonly seen in prison inmates
ideomotor apraxia
inability to carry out an action after a verbal command. They might be able to spntaneously do the actions- but not following commands to do so
drooping eyelids, diminished pupillary light reflex, and difficulty opening mouth are signs of what disease you can get from foods
clostridium botulinum
atonic seizures- what are they and why are they risky?
abrupt loss of muscle tone which cal lead to a fall/injury. The fall or injury is the risky part, not the loss of muscle tone itself.
