Fungal Meningits, Poliovirus, Polyoma Virus

Question 1

How do fungi get into CSF

Answer 1

from blood

Question 2

treatment for fungal meningitis

Answer 2

amp B and flucytosine

Question 3

cryptococcosis neoformans is transmitted by?

Answer 3

inhaled pigeon droppings

Question 4

85% of pts with cryptococcosis neoformans infections have what underlying condition?

Answer 4

HIV

Question 5

structure of cryptococcosis neoformans

Answer 5

encapsulated yeasts

**capsule is polysacchairde and anti-phagocytotic

Question 6

initial pres of cryptococcosis neoformans CNS infection

Answer 6

asympomatic pulm infection

Question 7

how is cryptococcosis neoformans CNS infection diagnosied?

Answer 7

yeasts with halos on india ink from CSF of pt

Question 8

fungal agent responsible for steriod outbreak

Answer 8

Exserohilum rostratum

= environmentala black mold

Question 9

structure of poliovirus

Answer 9

non-enveloped, icosahedral + RNA

Question 10

how is polio tranmitted

Answer 10

fecal- oral route

Question 11

reservior for poliovirus

Answer 11

humans

Question 12

where in the body does poliovirus replicate once infected

Answer 12

lymphoid tissue of pharynx and gut (virus detected in throat and feces) –> viremia –> cross BBB and destroy motor neurons

Question 13

what is post polio syndrome

Answer 13

inc weakness later in life

Question 14

how are vaccine strains distinguished from wild poliovirus

Answer 14

strain specific polyclonal area (specialized labs only)

Question 15

salk vs sabin vaccine

Answer 15

salk (IPV) = inactivated (by formalin); prevents reversion; protects against paralysis but NOT spread of wild virus

sabin (OPV) = live oral; protects againt paralysis AND spread of wild virus bit can be shed and revert and enter community

Question 16

Which vaccine is used in US

Answer 16

Salk = IPV

global eradication program uses OPV

Question 17

structure of polyoma virus

Answer 17

non-enveloped, icosahedral, dsDNA (circular genome)

Question 18

where in the cell does the polyoma virus repliate

Answer 18

NUCLEUS

Question 19

consequences of polyoma virus infection into permissive vs non-permissive cells

Answer 19

permissive = rep in nuc and lyse cell to release progeny

non-permissive = integrate into host genome and transform cell = tumor formation

Question 20

genes responsible for transformation and immortilization of non-permissive cells

Answer 20

3 genes: small, middle, and large T antigens

immortalization = small and large T antigen
transformation = small and middle T antigen

Question 21

what do the early genes of polyoma virus encode? late?

Answer 21

early = T antigens
late = structural protein

Question 22

what are the 2 known human polyoma viruses

Answer 22

JC and BK

Question 23

who gets infected with JC and BK virus? who gets cancer form them?

Answer 23

everyone gets infected but only AIDS and transplant pts get cancer

Question 24

describe where the BK and JC viruses replicate in the body?

Answer 24

where they enter (GI or respiratory tract) –> viremia –> kidney, lung, brain

Question 25

where do BK and JC virus have latent infection?

Answer 25

kindey

**in immunocomprosimed can lead to hemorrhagic cystitis

Question 26

etiologic agent of PML

Answer 26

JC virus

Question 27

What is PML

Answer 27

progressive demyelinating disease (lyses oligiodendrocytes) due to reactivation og JC virus

Question 28

presentation of PML

Answer 28

over the course of a few weeks clumsiness, weakness, speech problems

Question 29

diagnosis of PML made by

Answer 29

lesions in white matter on MRI

CSF or brain biopsy with PCR + for JC virus

Question 30

prognosis of PML

Answer 30

transplant = 80% fatality in 6 mos
HIV/AIDS = 50% in 6 mos due to HAART therapy