Cryptococcus neoformans

Question 1

type

Answer 1

ENCAPSULATED
YEAST
mono

Question 2

transmission and risk factors

Answer 2

Grows well in
soil enriched
by pigeon
droppings
- inhalation of
yeasts

Question 3

presentation

Answer 3

One of the most common
fungal infection in AIDS
patients

Question 4

pathogenesis

Answer 4

Inhalation triggers production of
capsule(composed of
glucuronoxylomannan(GXM)
Strong affinity for
CNS(neurotropic)
- Capsule detectable in
blood & fluids: regulate
immune response
- Oxidize exogenous
catecholamines →
melanin: prevent
fungi from
phagocytic oxidative
damage

Question 5

diagnostic

Answer 5

NARROW BASE
BUDDING
YEAST
Use India ink
stain for CSF
sample - stain
background and
not the organism
- thick capsule
gives halo
Mucicarmine stai
inner layer of
capsule