Block 4 Flashcards
what is acute atypical viral meningitis
meningeal signs without a known causative organisms
CSF analysis for viral meningitis
increased lymphocytes
increased protein
normal glucose
acute aseptic (viral) meningitis is usually caused by what virus
enterovirus (echovirus, coxsackie virus, polio)
what is the main viral cause of acute aseptic (viral) meningitis
enterovirus (echovirus, coxsackie virus, polio)
what is acute pyogenic meningitis
inflammation of meninges due to bacterial infection
what are the 2 most common causes of pyogenic meningitis
strep pneumoniae
neisseria meningiditis
what is the main symptom of infants with meningitis
bulging fontanelle
what are the 2 most common causes of pyogenic meningitis
strep pneumoniae
neisseria meningiditis
CSF analysis of pyogenic (bacterial) meningitis
cloudy
increased neutrophils
increased protein
decreased glucose
what are 2 gross morphology features of pyogenic (bacterial) meningitis
meningeal vessel engorgement
purulent exudate on the surface of the brain
what is the main microscopic feature of pyogenic (bacterial) meningitis
neutrophil infiltrate in subarachnoid space/perivascular spaces
what is a short term complication of pyogenic (bacterial) meningitis
phlebitis (venous thrombosis and hemorrhagic infarction)
what are 2 long term complication of pyogenic (bacterial) meningitis
-leptomeningeal fibrosis (adhesion of pia and arachnoid)
-communicating hydrocephalus
what are the 3 features of communicating hydrocephalus seen in pyogenic (bacterial) meningitis
-spasticity/hyperreflexia in limbs (stretch periventricular pyramidal tract)
-double vision (CN VI)
-blurred vision (papilledema)
gross morphology of acute pyrogenic (bacterial) meningitis with purulent exudate on the cerebral hemisphere with engorged meningeal vessels
purulent exudate on cerebral sulci as seen in acute pyogenic (bacterial) meningitis
increased neutrophil infiltrate seen on the left in the meninges as seen in pyogenic (bacterial) meningitis
what is the main cause of acute aseptic (viral) meningitis
enterovirus (coxsackievirus, poliovirus, echovirus)
meningitis with GI symptoms is most likely bacteria, viral, or fungal
viral
what is the treatment for acute atypical (viral) meningitis
usually self limiting
what is the treatment for acute atypical (viral) meningitis
usually self limiting
what is seen in CSF of those with acute atypical (viral) meningitis
increased lymphocytes
normal glucose
increase protein
what is seen in CSF analysis with meningitis caused by fungal or mycobacterial infection
increased lymphocytes
decreased glucose
brain abscesses are usually caused by what 2 bacterial infections
streptococcus
staphylococcus
what 4 settings can cause brain abscess due to streptococcus or staphylococcus infection
endocarditis
infected lungs
congenital heart disease/R->L shunt
immunosuppression
what are the 4 clinical features of brain abscess
intraparenchymal mass
liquefactive necrosis
increased ICP
HA, nausea, vomiting, seizure
what is the morphology of brain abscesses
central liquefactive necrosis surrounded by fibrous capsule and gliosis
what is gliosis as seen in brain abscesses
fibrous proliferation of astrocytes
brain abscess with liquefactive center
brain abscess to the left with normal tissue on the right
blue trichrome stain showing CT of the abscess
gliosis and fibrosis is seen in __ and __. everything else is only gliosis
CNS trauma
abscess
morphology of a brain abscess with engorged vessels and exudate on the surface
what is a subdural empyema
collection of pus between dura and arachnoid
subdural empyema can be caused by __ or __ infection
bacterial
fungal
what are 4 symptoms of subdural empyema
occlusion/infarction
fever
headache
neck stiffness
what is an extradural (epidural) abscess
inflammation involving a collection of pus between dura and bone (skull or spine)
what is Pott’s Puffy Tumor
sinusitis that leads to osteomyelitis
what are 3 causes of chronic bacterial meningoencephalitis
mycobacterium tuberculosis
treponema pallidum
borrelia species
what morphology is seen in tuberculous meningoencephalitis
fibrinous exudate in perivascular space at the base of the brain
well formed granulomas
what is the difference between mycobacterium avium intracellulare and mycobacterium tuberculosis in terms of granuloma formation
MAI- poorly formed granulomas
m. tuberculosis- well formed granulomas
TB meningitis with well formed granuloma
TB meningitis with exudate at brain base
mycobacterium avium intracellulare poorly formed granulmoa
what is seen in CSF in tuberculous meningitis
pleocytosis with occasional neutrophils
increased protein
normal or slightly decreased glucose
what are 2 complications of tuberculous meningoencephalitis
obliterative endarteritis–>infarction
arachnoid fibrosis–>hydrocephalus
what are 2 causes of neurosyphilis
tertiary stage of treponema pallidum
tabes dorsalis
meningovascular neurosyphilis is associated with __
obliterative endarteritis
what is paretic neurosyphilis
cortical atrophy with dementia from damage to the frontal lobe due to treponema organisms
what are 2 main symptoms of paretic neurosyphilis
mood alterations (grandiose delusions)
dementia
what occurs in tabes dorsalis
damage to the dorsal root sensory neurons leads to loss of proprioception, vibratory sense, and ataxia
what are 3 symptoms of neuroborreliosis (lyme disease) caused by Borellia Burgdorferi
facial nerve palsy
aseptic meningitis
encephalopathy
what is the difference in who is affected by herpes simplex 1 vs 2
1= immunocompromised young adults
2= infants due to vaginal exposure
herpes simplex virus affects what part of the brain
temporal/frontal lobe with necrotizing hemorrhage
what is the clinical feature of herpes simplex virus
alterations in mood, memory, and behavior
what 2 features are seen microscopically in herpes simplex virus
eosinophilic Cowdry A intranuclear inclusions
perinuclear halo
herpes simplex virus hemorrhage in the temporal lobe
Cowdry A intranuclear inclusion body in herpes simplex virus
what is the effect of cytomegalovirus in fetuses
microcephaly
calcified brain
what is the receptor of cytomegalovirus
integrin
what morphology change is seen with cytomegalovirus
periventricular necrosis with hemorrhage and calcification
what is seen microscopically in those with cytomegalovirus
intracytoplasmic and intranuclear inclusions with an “owl eye” appearance
“owl eye” inclusion bodies seen in cytomegalovirus
cytomegalovirus inclusion bodies
varicella zoster remains latent where before being reactivated as shingles
dorsal root ganglion
varicella zoster can cause __
encephalitis
encephalitis caused by varicella zoster is characterized by __ and __
demyelination
necrosis
what is post-hepatic neuralgia
pain in an area previously affected by shingles
polio virus usually causes __itis
gastroenteritis
poliomyelitis affects what structures
motor neurons of the ventral horn
what are the 3 main symptoms of polio
flaccid paralysis
hyporeflexia
muscular atrophy
poliomyelitis can cause death due to __
diaphragm paralysis
rabies virus attaches to what receptors
nicotinic cholinergic receptors using glycoproteins
does rabies virus ascend or descend
how long can it take
ascends (axonal transport)
1-3
rabies virus colonizes what 2 brain structures
cerebellum
hippocampus (temporal lobe)
what are the symptoms of rabies encephalitis
altered mental state
violent motor response
pharyngeal spasms
flaccid paralysis
death from rabies virus is due to what
respiratory center failure
with rabies virus, widespread neuronal necrosis and inflammation is most severe in what 3 strictures
basal ganglia
brainstem
spinal cord
what is seen microscopically in rabies
negri body eosinophilic cytoplasmic inclusions
negri bodies from rabies virus are found in what 2 cell types
hippocampal pyramidal cells
cerebellar purkinje cells
intracytoplasmic eosinophilic negri bodies seen in rabies virus
HIV infects what cell types
microglia
what receptors does HIV use
CD4 and chemokine
what is immune reconstruction inflammatory syndrome
deterioration after starting HIV therapy
what causes HIV associated dementia
HIV
what are 4 gross morphological features of HIV
microglial nodules
multinucleated giant cells
necrosis
gliosis
what 3 parts of the brain are affected most by HIV
subcortical white matter
diencephalon
brainstem
progressive multifocal leukoencephalopathy is caused by what
JC papovavirus
what cells does JC virus infect
oligodendrocytes
what type of inclusion is seen in progressive multifocal leukoencephalopathy
intranuclear
death from progressive multifocal leukoencephalopathy occurs due to __
diaphragmatic paralysis
subacute sclerosing panencephalitis is a sequela of what infection, especially in children
untreated measles
what are the 2 main clinical features of subacute sclerosing panencephalitis
cognitive decline
seizure
what 4 morphological features are seen in subacute sclerosing panencephalitis
inclusions in oligodendrocytes or neurons
demyelination
neurofibrillary tangles
gliosis
what 4 fungi can cause meningitis
histoplasmosis
blastomycosis
coccidiodes
cryptococcus
diabetic ketoacidosis is associated with what fungus
mucur
4 characteristics that can be seen microscopically of candida fugus
pseudohyphae (image)
hyphae
budding
germtube
soap bubble lesions are characteristic of meningitis caused by __
cryptococcus
multiple cyst like soap bubble lesions in perivascular space
soap bubble lesions of cryptococcus
besides soap bubble lesions, what is seen in cryptococcus
thick capsule
mucicarmine stain is characteristic for what infection
cryptococcus
besides mucicarmine stain, what other stain can be used for cryptococcus
india ink
mucicarmine stain showing cryptococcus
what fungus shows narrow base budding
cryptococcus neoformans
what fungus shows acute branching and acute septal hyphae
aspergillus
what fungus shows right angle branching
mucor/rhizopus
what fungus are spherical, thick walled spherules containing small uninuclear endospores
coccidiodes
aspergillus
mucor/rhizopus
coccidiodes
what fungus is found as intracellular yeasts inside macrophages
histoplasmosis
histoplasmosis found as intracellular yeasts in macrophages
what are 3 characteristics of fetal toxoplasmosis infection
cerebritis
multifocal necrotizing lesions
periventricular calcification
how are humans infected with toxoplasmosis
ingestion of fecal oocyte of tissue cyst from cat feces
what shows in imaging for toxoplasmosis
multiple ring-enhancing lesions
encephalitis caused by toxoplasmosis may result from tachyzoites infecting what cells
astrocytes
abscesses caused by toxoplasma contain __ and __
tachyzoites and bradyzoites
calcification of the brain may occur in what 2 infections
toxoplasmosis
congenital cytomegalovirus
toxoplasmosis with multiple ring enhancing lesions
toxoplasma bradyzoites in cysts in astrocytes
which parasite causes dystrophic brain calcifications
toxoplasma
acanthamoeba meningoencephalitis is characterized by __
focal granulomatous lesions
acanthamoeba encephalitis
how do naegleria meningoencephalitis and acanthamoeba encephalitis differ in brain structure impact
naegleria meningoencephalitis causes diffuse meningoencephalitis
acanthamoeba causes focal, granulomatous lesion
how does infection occur with naegleria meningoencephalitis
nasal–>cribiform plate—>olfactory nerve–>brain
how does infection occur with acanthamoeba encephalitis
lower respiratory tract ulcerated skin/mucosa–>blood stream–>CNS
what is a major cause of mortality from P. falciparum
cerebral malaria
what are 4 consequences of cerebral malaria
ataxia
seizure
coma
long term cognitive deficits
what parasite causes neurocysticercosis
taenia solium from pork
what is the main cause of acquired epilepsy in developing countries
neurocysticercosis
typical cases of neurocysticercosis are from __
immigrants from latin america and asia
cysticercotic encephalitis is characterized by what 3 features
edema
collapsed ventricles
multiple enhancing lesions
seizures/epilepsy, abnormal behavior, HA, stroke, and rarely a fever all characterize what infection
neurocysticercocsis
rickettsia CNS infection can cause ___
aseptic meningitis
what are physical findings of rocky mountain spotted fever complications caused by rickettsia
hemiplegia
athetosis (slow worm-like movement of limbs or trunk)
transverse myelitis
(occasional CNS vasculitis)
what type of neurodegeneration occurs with transmissible spongiform encephalopathy (prion disease)
rapidly progressive
what causes the spongiform changes in the brain seen with transmissible spongiform encephalopathy
neuronal and glial intracellular vacuoles (holes in glial cells)
what change occurs in prions that leads to pathogenesis
alpha helix to beta sheet activates the protein
what genetic link is there in Creutzfeldt-Jakob disease
PRNP gene increases the risk of PrPsc formation
what is seen microscopically in those with Creutzfeldt-Jakob disease
spongiform transformation of grey (cerebral cortex) and deep grey
(caudate/putamen) matter
what is seen morphologically in Creutzfeldt Jakob disease
neuronal loss
reactive gliosis
vacuoles in neurons
corneal implant/transplant, contaminated human growth factor, and deep implantation of electrodes in the brain have all been known to cause ___
Creuzfeldt Jakob disease
what are 3 consequences of Creuzfeldt Jakob disease
dementia/memory changes (cortical lesion)
involuntary jerks (basal ganglia)
death in less than 1 year
myoclonic jerks in a young patient with acute neurological deterioration with mood changes is characteristic of ___
Creuzfeldt Jakob
does Creuzfeldt Jakob or Varient Creuzfeldt Jakob disease have a mutation in PRNP gene
Creuzfeldt Jakob
how is variant Creuzfeldt Jakob disease (Mad Cow disease) acquired
blood transfusion
infected meat
is variant Creuzfeldt Jakob disease (Mad Cow disease) slow or fast progressive
slow
progressive cerebellar ataxia is seen in what prion disease
Gerstmann Strausser Scheinker
what neurological structural effect is seen in fatal familial insomnia
neuronal loss in thalamus
reactive gliosis
what are 2 ways in which astrocytes adapt to injury
hypertrophy
hyperplasia
(gliosis)
how do oligodendrocytes adapt to injury
demyelination
how does ependyma react to injury
passive submission
how do microglia respond to injury
granulomatous inflammation
microglial nodules
scars
how do microglia differ from gitter cells
microglia have elongated nuclei lack visible cytoplasm
gitter cells have small round nuclei with abundant cytoplasm
red neurons 12-24 hours after injury
gitter cells
*macrophages stuffed with debris
what are gemistocytic astrocytes
astrocytes filled with cytoplasm containing glial filaments and eccentric nucleus
gemistocytic astrocyte
neovascularization
perinatal brain injury with hypoxia lead to __
cerebral palsy
prolonged jaundice can lead to what in a newborn
kernicterus
intraventricular hemorrhage (germinal matric hemorrhage)
what is seen histologically in infants with intraventricular hemorrhage (germinal matric hemorrhage)
blood cells intermingled with parenchyma and noncohesive germinal matrix cells
what is one of the main symptoms of kernicterus
hearing loss
what causes kernicterus
high levels of bilirubin
what are the regions of the brain most commonly affected by kernicterus
basal ganglia (especially globus pallidus and subthalamic nucleus)
kernicterus
kernicterus
cause of intraparenchymal nontraumatic heorrhage
hypertension
cause of subarachnoid nontraumatic hemorrhage
berry aneurysms
what is the size of Charcot Bouchard microaneurysms
<1mm
hypertensive hemorrhage
berry aneurysm is commonly associated with what 3 diseases/disorders
polycystic kidney disease
type IV Ehler Danlos
Marfan
medial defect aneurysms are often associated with __ and __
valsava
orgasm
a sudden, excruciating headache can be due to __
medial defect aneurysm
berry aneurysm most commonly occurs at what artery
*anterior communicating
anterior cerebral
subarachnoid hemorrhage
ruptured AVM hemorrhage age range is usually __-__ years
subarachnoid hemorrhage age range is usually __-__ years
AVM= 10-35
subarachnoid= 35 and above
3 clinical symptoms of normal pressure hydrocephalus
abnormal gait
urinary incontinence
bradyphrenia
dementia
what is the characteristic of CSF in normal pressure hydrocephalus
normal
what are 4 characteristics that point in the direction of normal pressure hydrocephalus
40 years or older
abnormal gait
urinary incontinence
dementia
how can normal pressure hydrocephalus be differentiated from dementia
the onset of gait and urinary symptoms is usually not as early in progression in dementia as it is in normal pressure hydrocephalus
what is hydrocephalus ex vacuo
enlargement of CSF spaces in response to brain parenchyma loss
hydrocephalus ex vacuo
how can you differentiate a hemorrhagic infarct from a thrombotic infarct
hemorrhagic occurs suddenly
thrombotic evolve over time
what is the most common site of a cerebral infarct
middle cerebral artery
middle cerebral artery infarct
middle cerebral artery infarct
embolic infarct
what is seen with bone marrow embolization
white matter hemorrhages
massive “shower” fat embolism of bone marrow
what are 4 causes of global ischemia
CO poisoning
MI/cardiogenic shock
hypovolemic shock
septic shock
border zone “watershed” infarcts are commonly seen after ___
hypotension
what site is at the greatest risk for border zone “watershed” infarct
anterior cerebral artery-middle cerebral artery intersection
what are 3 factors seen with hypertensive cerebrovascular disease
lacunar infarct
hyaline arteriolar sclerosis
slit hemorrhages (<15mm vessel rupture)
hypertensive encephalopathy is associated with what 2 symptoms
edema
herniation
lacunar infarct with hyaline arteriolar sclerosis
lacunar infarcts affect what 2 brain structures the most
basal ganglia
brainstem
lacunar infarcts with hyaline arteriolar sclerosis involve __mm vessels while Charcot Bouchard microaneurysms involve __mm vessels
<15mm
<1mm
slit hemorrhages are mainly caused by __
hypertension
what is seen microscopically with slit hemorrhages
pigment laden macrophages
what are the 2 most common sites for hypertensive intracranial hemorrhages
basal ganglion (putamen)
internal capsule
what is the Cushing Response
the nervous system response to increased ICP
what is the Cushing’s triad seen in the Cushing Response
increased BP
irregular breathing
decreased HR
if astrocytes are involved, GFAP will stain positive or negative
positive
no p53 loss occurs in what type of astrocytoma
pilocytic astrocytoma
what type of astrocytoma is associated with p53 loss and PGDF A overexpression
well differentiated astrocytoma
the transition to a higher grade astrocytoma is associated with disruption of what tumor suppressor genes
RB
p16/CDKNaA
loss of RB and p16 is associated with what type of astrocytoma
anaplastic astrocytoma
EGFR amplification is associated with what type of astrocytoma
glioblastoma
pilocytic astrocytoma is rated a grade __
I
