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* CNS Biopsy
  yelito61 - 10/31/06 23:09
  A 7-year-old girl develops a fever, conjunctivitis, photophobia, and a cough. Her pediatrician notes white spots on a bright red background on the girl's buccal mucosa. Within days, a rash begins around the hairline, then spreads to the trunk and extremities. One week later, the child suddenly begins to convulse, and loses consciousness. She is taken to the emergency room, where involuntary movements and pupillary abnormalities are noted. Which of the following would most likely be seen on CNS biopsy?

A. Demyelination of white matter of cerebral hemispheres with abnormal giant oligodendrocytes
B. Perivenous microglial encephalitis with demyelination
C. Phagocytosis of motor neurons in the spinal cord
D. Severe hemorrhagic and necrotizing encephalitis of the temporal lobe with eosinophilic Cowdry type A inclusion in neurons and glia
E. Small granulomas with central caseation in the meninges

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* Re:CNS Biopsy
  bep111 - 10/31/06 23:12
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* Re:CNS Biopsy
  cd45 - 10/31/06 23:14
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* Re:CNS Biopsy
  yelito61 - 10/31/06 23:15
  Yes bep 111, you're completely right.

The correct answer is B. The initial history given is classic for measles, with the appearance of Koplik's spots (white spots on the buccal mucosa) followed by a rash beginning along the neck and hairline and spreading to the trunk and extremities. The sequela this child is experiencing is post-infectious encephalomyelitis, which can follow either infection with measles, varicella, rubella, mumps, or influenza, or vaccination with vaccinia vaccine or rabies vaccine derived from nervous tissue. Treatment is supportive, with a mortality of 15 to 40%; survivors frequently have significant permanent neurologic deficits. The pathologic finding is perivenous microglial involvement with demyelination.

Choice A describes the findings of progressive multifocal leukoencephalopathy, a demyelinating disease caused by infection with JC virus, especially in immunocompromised individuals.

Choice C describes the findings of poliomyelitis, a paralytic disease affecting the ventral horn of the spinal cord and motor cortex, caused by an enterovirus (poliovirus).

Choice D describes the findings in herpes encephalitis, which typically affects the inferomedial temporal lobes and orbitofrontal gyri.

Choice E describes the findings in tuberculous meningitis, caused by M. tuberculosis.

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* Re:CNS Biopsy
  sage2006 - 10/31/06 23:17
  hmm, CD45, how dare you picked a wrong one... it is qbank q...  
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* Re:CNS Biopsy
  cd45 - 10/31/06 23:32
  hmm i think cause i still have some 40 qs in path to go thats why. heheheee

anyways i have been totally abusing qbank... i just review my wrong answers.. maybe when i did this one i got it right and now i dont remem :(((
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