28. Neuropath: Infectious Diseases Flashcards
Osteitis: inflammation is where?
bone of skull/spine
Epidural empyema: inflammation is where?
pus in epidural space
pachymeningitis: inflammation is where?
dura
subdural empyema: inflammation is where?
pus below dura and above arachnoid
ventriculitis: inflammation is where?
ventricular lining
leptomeningitis: inflammation is where?
pia and arachnoid
meningitis: inflammation is where?
membranes (pia and arachnoid)
encephalitis: inflammation is where?
brain substance/parenchyma
myelitis: inflammation is where?
spinal cord
radiculitis: inflammation is where?
nerve root
neuritis: inflammation is where?
nerve
slow viruses aka prions: what is histopathology appearance, in general?
spongiform encephalitis
what is a prion?
infectious protein
CJD: what population is it most prevalent in? how does it present?
older people. will have subacute dementia evolving over a few months. may be social/cognition problems, visual probs. may be startle myoclonus. irreversible.
nvCJD: what is the origin of this disease? presentation?
new-variant CJD: this is mad cow as it appears in humans. tends to occur to younger people but presentation is similar to CJD.
Gerstmann-Straussler: presentation? prognosis?
genetic disease. causes cerebellar ataxia, and after a year or two patients become demented and die.
how do we know that prions are proteins?
they are sensitive to proteases.
CJD: gross brain appearance?
slight atrophy but otherwise normal
CJD: histological appearance?
extensive neuronal loss. causes gliosis, spongiform appearance. atrophy of white matter since neurons have gone and myelin is resorbed.
wtf is gliosis?
proliferation/hypertrophy of glial cells in response to insult. can lead to a glial scar.
we have prions normally: what is the difference between our normal prions and those that cause disease?
mutations cause pathologic variants.
general characterization of viral illnesses in the CNS?
can be dead in 5 days. acute, rapid progression, serious, life threatening.
what is the poster child for CNS viruses? where does it tend to localize? what damage does it cause?
HSV encephalitis. likes the temporal lobe. hemorrhagic and necrotic. can cause edema –> transtentorial herniation.
on histology, lymphocytic infiltrate that goes from vessels to neural parenchyma indicates what kind of problem?
virus (rather than bacteria or infarction)
classic histologic sign for viral encephalitis?
lymphocytic inflammatory response, death of neurons/glial cells, perivascular lymphocyte cuffs, microglial nodules, may see inclusion bodies.
what is a microglial nodule/cluster? what does it indicate?
site where neuron has died, been eaten by microglial cells via neuronophagia. indicates viral disease.
inclusion bodies in nuclei indicate what kind of problem?
viral until proven otherwise.
viral infection: what will CSF show?
elevated WBCs (usually lymphocytes), elevated protein, normal glucose.
for what disease is the CNS its second target organ?
HIV.
what are some of the diffuse CNS functions affected by HIV?
multiple mental functions are impaired: attention, motor, visual recog, verbal learning.
how does localization of the CNS area affected help in diagnosing viral infection?
each virus has a favorite location to invade.
what is the AIDS-dementia complex?
subacute dementia. HIV infects cells in the brain which produce toxins, which damage/kill neurons and oligos.
histologically, what would a slide of a patient with HIV-encephalitis look like?
microglial nodule: typically around blood vessels. population of macrophages/monocytes
HIV-encephalitis: the perivascular giant cells can produce what? leads to what problems?
produce inflammatory cytokines, leads to diffuse inflammation of the brain parenchyma.