2 M18 quiz

• Cryptococcus neoformans Meningitis (Cryptococcosis)

  • Soil fungus associated with pigeon and chicken
  • Transmitted by the respiratory route through dried contaminated droppings
  • In the immunocompromised, it spreads through blood to the CNS
  • Diagnosis: latex agglutination
  • Mortality of up to 30%
  • Treatment: Amphotericin B and flucytosine
• African Trypanosomiasis

  • Transmitted from animals to humans by the tsetse fly
  • Distributed in west and central African
  • Few early symptoms, followed by fever, headache, and deterioration of the CNS
  • Parasite evades antibodies through antigenic variation
  • Difficult for vaccine development
  • Treated with eflornithine: crosses the blood-brain barrier; blocks an enzyme necessary for the parasite
  • Prevention: elimination of tsetse fly vectors
• Trypanosoma brucei gambiense

  • Humans are the only reservoir

  T. b. rhodesiense

  • Reservoir in livestock and wild animals
• Amebic Meningoencephalitis

  l. Naegleria fowleri

  • Causes primary amebic meningoencephalitis (PAM)
  • Protozoan infects the nasal mucosa from swimming water, penetrates the brain, and feeds on brain tissue
  • One hundred percent fatal

  ll. Acanthamoeba

  • causes granulomatous amebic encephalitis (GAE)
  • Granulomas form around the site of infection, forming multiple lesions around the brain
• Prion: abnormally folded protein

  • Causes normal proteins in the brain tissues to become abnormally folded
  • Lead to spongiform degeneration
  • Chronic and fatal
  • Transmissible spongiform encephalopathies (TSE) (causes pathogenic)

  Sheep scrapie

  • TSE in sheep

  Chronic wasting disease

  • TSE in deer and elk

  Creutzfeldt-jakob disease (CJD)

  • TSE in humans
• Kuru

  • TSE in humans that is caused by cannibalism

  Bovine spongiform encephalopathy (BSE)

  • Mad cow disease
  • Possibly due to cattle eating feed containing bone meal from scrapie-infected sheep