mycology Flashcards
1
Q
what makes a fungus
A
- eukaryotes (have membrane enclosed nucleus)
- heterotrophs (require pre formed source of C for growth (secrete degradative enzymes)
- saprophytic (obtain nourishment from dead matter)
- parasitic (obtain nourishment from live organic matter)
- often take form as respiratory or skin infections
- mycosis should always be considered in immunocompromised patients
- specialized antifungal agents are needed to treat
2
Q
fungal cell walls
A
made of chitin (bacteria peptidoglycan)
- means not affected by ABX!!
- contain ergosterol (human cell walls don’t contain this so antifungals don’t kill human cells)
3
Q
How fungal cells grow
A
- filamentous
- yeast like
- dimorphic
4
Q
filamentous fungi
A
- “mold like”
- the vegetative body is a mass of threads with many branches. the mass is a mycelium which grows by branching and tip elongation.
5
Q
yeast like fungi
A
- single unconnected spheroid cells, reproduce by budding
- spaghetti and meatballs
6
Q
dimorphic fungi
A
-yeast like in one environment and mold like in another. they can be air or water borne where they germinate and establish new colonies. They reproduce either sexually or asexually.
7
Q
fungal reproduction
A
- sporulation (with and without sex, most human pathogenic fungi reproduce asexually)
- spores are metabolically dormant (released in huge numbers via wind and water then germinate to establish new colonies)
8
Q
Lab diagnosis
A
-under scope with KOH prep (KOH digests keratin)
9
Q
classification of pathogenic mycoses
A
- where on body they infect (cutaneous, subcutaneous, systemic)
- what type of body they infect (healthy vs immunocompromised)
10
Q
cutaneous pathogenic mycoses
A
- dermatophytes!!
- reside on humans, animals, soil
- infect superficial keratinized structures (hair, skin, nails)
- human to human or animal transmission
- diaper rash! (fester in warm, moist environments)
11
Q
subcutaneous pathogenic mycoses
A
- infect dermis, subcutaneous, tissue and bone
- reside in soil or decaying vegetation
- acquired through traumatic lacs or puncture wounds (usually in tropical enviorns)
12
Q
systemic pathogenic mycoses
A
- some can infect healthy people
- some primarily infect sick people
- usually confined to geographic areas
13
Q
if get fungal infection, what do you wonder?
A
- is pt immunocomp? do they have aids? diabetes?
- if someone on abx and still sick, wonder fungus?
14
Q
opportunistic
A
- type of systemic pathogen
- infect immunocompromised host (BM transplant, AIDS, chemo, etc)
- may be normal flora going out of control
15
Q
candida
A
- oral or cutaneous candidal dermatitis
- yeast growth in different areas
