micro bio related neuro Flashcards
35 yo man dvps hemiparesis, homonymous hemianopia and cognitive deterioration. MRI shows widespread abnormal T2 in white matter, EEG show diffuse slowing over both cerebral hemispheres. Tissue biopsy: demyelination w/abnormal giant oligodendrocytes, some of which contain eosinophilic inclusions. What is pt’s condition? It occurs most commonly in assoc w/which disease?
Condition is Progressive Multifocal Leukoencephalopathy (PML) - a rapidly progressive demyelinating disorder in which the JC virus (polyomavirus) infects oligodendrogial cells in the brain.
Disease: AIDS- PML occurs in about 1% of AIDS pt
symptoms of PML (Progressive multifocal leukoencephalopathy)-
aphaseia, cortical blindness, hemiparesis, ataxia, conjugate gaze abnormalities. The condition can progress to quadriparesis and coma-
txt for PML (progressive multifocal leukoencephalopathy)
there is no txt
encephalitis that affects the gray and white matter and subacute sclerosing panencephalitis (SSPE) (usually seen before the age of 18) can result from prior ifxn with…
measles
measles infection can later lead to…
encephalitis that affects the gray and white matter and subacute sclerosing panencephalitis (SSPE) (usually seen before the age of 18)
immunologic basis of MS pathology…
TH1 lymph. reactive agst myelin stimulate macrophages to destroy myelin.
MS is an example of what type of hypersensitivity response?
Type IV
MS has relapsing and remitting symp that may involve…
visual impairment, cranial nerve signs, ataxia, nystagmus, internuclear ophthalmoplegia. Spinal cord lesions give rise to motor and sensory difficulties of trunk and limbs and spasticity and loss of control of bladder func.
treatment of MS with natalizumab is associated with an increased risk of…
PML (progressive multifocal leukoencephalopathy)
the eosinophilic inclusions (Negri bodies) produced in rabies are bound where?
gray matter of the brain
signs of rabies include…
excessive salivation, hallucinations and hydrophobia
syphilis can cause. what damage to the CNS?
meningitis, encephalitis and spinal cord damage- affecting white and gray matter
tuburculosis can cause what in the CNS?
granulomatous meningitis, typically affeting the base of the brain
What is PML? what is it caused by?
progressive multifocal leukoencephalitis is a viral encephalitis caused by JC polyomavirus
PML infects what in the brain, causing what?
oligodendrocytes causing demyelination
PML is characterized by what?
multifocal lesions in the hemispheric or cerebellar white matter.
drooping eyelids, diminished pupillary light reflex, and difficulty opening mouth are signs of what disease you can get from foods
clostridium botulinum
why does clostridium germinate spores and produce toxins in canned goods and preserved fish/vacuum sealed things?
bc it’s anaerobic
how do you treat botulism?
supportive txt (watch for resp arrest!) there’s an antidote, but usually can’t get it quick enough
a 1 wk old newborn has irritability, fever and is developing a stupor. A lumbar puncture is perfomed and CSF shows high neutrophils. The neutrophils indicates that the meningitis ifxns is bacterial, viral, fungal or other?
bacterial!
if a 1 wk old presents with bacterial meningitis, the most likely pathogen has what gram stain and shape?
Gram-positive coccus (Group B strep (streptococcus Agalactiae))
if a 1 wk old presents with bacterial meningitis, what is the most likely pathogen?
Group B strep– a Gram-positive coccus
an acid fast bacillus describes what type of bacterium? do thees cause neonatal meningitis?
a mycobacterium, which do not cause neonatal meningitis
double stranded DNA virus with nuclear membrane envelope describes a virus in what family?
herpes family
do herpes family viruses cause neonatal meningitis?
no- they may cause encephalitis, but wouldn’t likely cause meningitis
what is the second leading cause of neonatal meningitis, and what is the gram stain/shape of that bacteria?
Escherichia coli- a gram-neg bacillus
a gram negative diplococcus describes what three genera?
neisseria, moraxella and Veillonella
which gram neg diplococcus causes meningitis and in what age group does it cause it?
neisseria meningitidis causes meningitis in adolescents and young adults
what is the third most common cause of neonatal meningitis and what is the gram stain/shape?
gram pos bacillus
listeria monocytogenes causes what in new borns?
3rd most common cause of meningitis
gram stain/shape of listeria monocytogenes?
gram-positive baccilis
