Mycology Flashcards
(22 cards)
yeast
single cell, budding, infection stage
molds
multcell, hyphae, condidal
contagion of fungi infxn
no P2P, spore inhalantion, direct inoculation, contact with hostpiakl ppl
monomorphic and dimorphic molds
mono always molds
di is mold at room temp in ENVIRO
OOORRRRR
yeast/spirulesand BODY temp (37)
growth rate of mold and yeast
mold is slow. yeast is fast.
histology of aspergillous, zygomyces, candida
asp: hyphae, septae, dichotomous 45 degree angle branching
zygomyces: no septa, irrg shaped, fat, 90 degrees, broad
candida: mor eparalell… <><><><> kinda like that but oval shaped
anti fungal drug targets
- cell membrane
- dna synthesis
- cell wall
b13 and b16 glucan because it is not in mammal cells. chitin. egesterol (membrane) in stead of cholesterol
how can you follow a patient as far as fungal infxn’s go?
B13 and B16 glucan and mannoproetins are made as fungi grow so if it spikes you know a pt may have a fungal infection
polyenes
azoles
flurinatoed pyrimidine
echinocandins
polyenes- membrane distrupting - ampho b
binds to sterols in cell membrane
azoles - estergol synthesis inhibitor - cell membrane
bind got lanosterol 14 a demethylase)
fluronated pyrimidine - nucleic acid inhibitor
echoincandids - glucan synthesis inhibitors
these aren’t in mammals so it has low toxicity!
histology of fungi before and after abx exposure
before: smooth, budding, fuzzy
after: lose form, crenated
MIC
if less than 8 micrograms per mL - considered susceptible
MIC is actually the lowest conc of anti fungal that demonstrates no growth - wanna keep tx level above it.
superficial fungal dz
outermost layer of skin and hair
low path, no inflame, no immune rxn, no pain
iue. tinea nigra
cutanous fungal dz
invasive hair and nail and deeper epidermis
ring worm
animal to human
tinea corposis
subq fungal dz
dermis, sq, muscle and fascia
sp trauma and saphrophytic molds, lesion at site of injury can spread
sportichrosis
systemic
primarily in lung then spread to other organs
self limited. resolution gives life long immunity, geo restricted
examples forthcoming
opportunistic
ie. candida
sportrichosis
subcutanesous
dimorphic gardening chronic skin infxn nodular lesions to lymph nodes can be pulm if inhale spores slow pregression
histo: astroid body with eosinophilic pink and white circle inside
histoplasmic capsulatim (+ 3 forms)
systemic
dimorphic
survive in macrophage
Fe and Ca
- acute primary pulmonary - flu like
- progressive pulmonary - if prev COPD
- progressive disseminated - must be immunocomp. scattered infected macrophage throughout resp and immune organs
candidiasis
opportunistic
gram NEG rods
mucous membranes
c. albicans
thrush, esophagitis, vag, endocarditis fungemia
appear as budding yeast and pinched psuedohyphae in tissue
cryptococcus
opportunistic
c. neoformans is the only pathogenic one in the genus
capsule
soil and pigeon droppings
inhaled for hmans
brain and meninges, lung, etc
CHECK CSF- low glucose high WBC
appears as budding yeast in tissue
histology —- indicative is a HALO*****
aspergillosis
opportunistic
soil and decaying organic matter
likes to invade vasculature and cause thrombosis infarction and necrosis
in tissue appear as hyaline, septa hyphae and branch dicot and 45 deg angles
SPORES!
ulcerative skin lesions of hard palate and sinuses?
zycomyces
faster than any other fungi
opportunistic
soil and decaying stuff
vascular invasion likely
causes rhinocerebral, pulm. cutaneous, gi, etc
in tissue it appears as hyaline broad non setptaed hyphae with irreg branching.
rhizoirds stolons and condidospore
