Mycology Lecture 6 Flashcards
adaptive defenses are _______, take longer to ______, and include __ cell and ______ responses
specific, respond, T, antibody
innate defenses are _________, respond _____, and are responsible for fever, redness, pain, and pus
non-specific, quickly
neutrophils are part of the ____ immune system
innate
antibodies are part of the ____ immune system
adaptive
T cells are part of the ____ immune system
adaptive
neutropenia is linked to what infections? (3)
- aspergillus
- mucormycosis
- candida
antibodies play an _____ role in fungal disease
unclear
T cells are important in _______, _____ _____ transplant, and ______
HIV/AIDS
solid organ
steroids
what are the main players involved with fighting fungal infections?
T cells
name a few non-immune factors that play a role in host defenses
- mechanical barriers (skin, mucosa)
- competition for nutrients from bacterial flora
- mucociliary clearance of respiratory tract
- iron overload
________ and _______ are significant in the first steps of host defense
neutrophils and macrophages
t or f: macrophages and neutrophils can be attracted by fungi or from signaling from other phagocytes that are already at the site of infection
true
phagocytes can destroy fungi via ______ or ___-______ mechanisms
oxidative, non-oxidative
t or f: to help with immunity formation, phagocytes are able to displayed ingested fungal part on their surface
true
what two features of cryptococcus allow it to evade the immune system?
capsule, melanin
which azoles can treat candida?
fluconazole (for non-resistant species like c. albicans and c. parapsilosis)
which azoles can treat aspergillus?
voriconazole (first line), isavuconazole, posaconazole
which azoles can treat mucormycosis?
azoles are used for second line of therapy (posaconazole, isavuconazole)
*first line therapy is ampho in high doses
name 4 major places that antifungals attack
- cell membrane function
- cell wall synthesis
- nucleic acid synthesis
- ergosterol synthesis
why was liquid amphotericin B created?
it was created to reduce the side effects that came along with use of amphotericin B (loss of kidney function and electrolyte imbalance)
liquid amphotericin B is a _____ option compared to the conventional amp B
safer
azoles inhibit _______ synthesis by binding to _____. this leads to a lack of ergosterol in cell _____, and a buildup of the precursor.
ergosterol
ERG11
membranes
primary resistance (intrinsic) is typically seen in ______ patients, where there is _______ of ______ species or subpopulations
immunocompromised
selection
resistant
secondary resistance (acquired) is seen in ____ patients or ______ patients. Patients with ____ may have recurrent candidiasis and may be on long-term fluconazole therapy, where there may be a _______ or ______ of drug efflux pumps.
AIDS neutropenic AIDS mutation upregulation
what are CDRs and MDR?
transport proteins found in the fungal cell wall - they pump antifungal drugs out
an example of secondary resistance w/ azoles is if Erg11 gets a ______ where it decreases binding to _____
mutation
azoles
an example of secondary resistance w/ azoles is if there is an issue in the ________ biosynthetic pathway, which leads to buildup of precursors
ergosterol
t or f: CDRs are usually _____ to all _____, whereas MDR is ______ for _______
generalized, azoles, specific, fluconazole
_______ and tolnaftate also inhibit ergosterol synthesis, but specifically ______
terbinafine
ERG1
5-FC is rarely used alone, because…..
it quickly develops resistance
side effect of 5-FC?
bone marrow toxicity
spectrum for 5-FC?
narrow
when is 5-FC used?
it is used to treat crypto meningitis (used with ampho B), candida (normally never use), chromoblastomycosis (not for long term)
name an example of a polyene and what it does?
amphotericin B
-it binds to ergosterol and destabilizes the membrane (punches pores in it)
side effect of amphotericin B?
nephrotoxicity
when 2g of ampho B is used, about __% of patients develop acute renal failure
50%
t or f: while liquid ampho B does reduce nephrotoxicity, it does not protect against it
true - it just reduces toxicity
what do echinocandins do?
they inhibit cell wall synthesis by inhibiting beta-1,3 D glucan synthase
echinocandins lead to loss of ____, thus leading to ____ fragility
glucan, osmotic
what is the spectrum for echinocandins?
- candida species resistant to fluconazole
- aspergillus species
**no coverage for cryptococcus neoformans
downside of using echinocandins?
IV administration only
downside of using voriconazole?
hallucinations, vivid dreams
what is the yeast connection?
the belief that yeast in our body causes a variety of health issues
what is the candida diet?
a low sugar / anti-inflammatory diet that encourages gut health and eliminates sugars that feed candida
candida plan supplements can lead to ____ failure. also, supplements are not ___ regulated
liver
FDA
what is yeast free?
supposedly a natural medicine used to clear fungal/yeast overgrowth, and c. albicans infections
