Antifungal chemotherapy Flashcards Preview

Year 2 Pharmacology > Antifungal chemotherapy > Flashcards

Flashcards in Antifungal chemotherapy Deck (45)
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1
Q

what are the opportunistic fungal infections?

A

candida
aspergillus
cryptococcus

2
Q

onychomycosis causes what type of fungal infection?

A

cutaneous / subcutaneous

3
Q

dimorphic fungi usually cause what type of infection?

A

systemic

4
Q

what are the unique targets for fungi?

A

fungal cell membrane (ergosterol, ergosterol synthesis)

fungal cell wall (glucans)

5
Q

what is the MOA of amphotericin B?

A

weaken membrane function (bind ergosterol)

forms amp B containing pores to alter membrane permeability

6
Q

caspofungin targets what fungal component / process?

A

cell wall synthesis

7
Q

5-flurocytosine targets what fungal component / process?

A

nucleic acid synthesis

8
Q

what are the systemically active drugs used for systemic infections?

A

polyenes
azoles
flucytosine
echinocandins

9
Q

what is the most widely used drug in treating systemic mycoses?

A

amphotericin B

10
Q

what drug has the broadest spectrum of action and is useful against systemic fungal infections?

A

amphotericin B

11
Q

when does amphotericin B resistance occur?

A

decrease in membrane ergosterol concentration

modification of target - reduced affinity

12
Q

what is the tissue penetration profile of amphotericin B?

A

widely distributed into most tissues but poor CNS penetration

13
Q

what is the most common and most serious long term toxicity associated with amphotericin B?

A

nephrotoxicity

14
Q

what is done to make amphotericin B less toxic? why?

A

liposomal packaged formulations

less interaction of drug with mammalian cell membrane

15
Q

what is the MOA of the azoles?

A

inhibit ergosterol synthesis - bind to enzyme responsible for converting lanosterol to ergosterol

causes leaky membranes

16
Q

what are the clinical uses for the azoles?

A

pathogenic yeast
systemic mycoses
dermatophytes

17
Q

what are the adverse reactions of the azoles?

A

minor GI disturbances

interaction with hepatic cyp450s

18
Q

what are the MORs of the azole drugs?

A

efflux pumps
mutations in target enzyme
decreased ergosterol content in cell membrane

19
Q

which azole has the highest therapeutic index of all the azoles?

A

fluconazole

20
Q

fluconazole is the agent of choice for what conditions?

A

candidiasis
cryptococcosis
coccidiomycosis

21
Q

what is the drug of choice for candidiasis, cryptococcosis, and coccidiomycosis?

A

fluconazole

22
Q

what is the drug of choice for blastomycosis, coccidiomycosis, histoplasmosis, sporotrichosis, and dermatophyte?

A

itraconazole

23
Q

itraconozole is the drug of choice for what conditions?

A
blastomycosis 
coccidiomycosis 
histoplasmosis 
sporotrichosis 
dermatophyte
24
Q

what drug has replaced amphotericin B as treatment of choice for aspergillosis?

A

voriconazole

25
Q

what is the drug of choice for aspergillosis?

A

voriconazole

26
Q

what azole has the highest spectrum of activity?

A

posaconazole

27
Q

what are the main indications for posaconazole?

A

aspergillus

agents of mucormycoses

28
Q

flucytosine is used as part of combination therapy for what organisms?

A

cryptococcus

candida

29
Q

what is the MOA of flucytosine?

A

interferes with both protein and nucleic acid synthesis

30
Q

flucytosine is effective against which organisms?

A

cryptococcal infections

31
Q

what test is used to identify cryptococcus neoformans?

A

india ink stain

32
Q

the india ink stain is used to identify which organism?

A

cryptococcus neoformans

33
Q

which drug is effective against cryptococcus neoformans and meningitis?

A

flucytosine

34
Q

what is the main toxicity of flucytosine?

A

bone marrow suppression

35
Q

what is the general MOA of the echinocandins? what dictates their selectivity?

A

inhibit fungal cell wall synthesis

attack beta glucans (not present in mammalian cells)

36
Q

what are the main indications for the echinocandins?

A

candida and aspergillus

37
Q

what are the oral systemic drugs for cutaneous and mucocutaneous infections?

A

griseofulvin

allylamines (terbinafine)

38
Q

griseofulvin and allylamines (terbinafine) are used for what purposes, generally?

A

cutaneous and mucocutaneous infections

39
Q

what drug is used orally for dermatophyte infections?

A

griseofulvin

40
Q

what specific infection is griseofulvin used for?

A

dermatophyte

41
Q

what is the MOA of the allylamines?

A

ergosterol synthesis inhibitors

42
Q

what is the first line treatment for onychomycosis?

A

terbinafine (allylamine)

43
Q

terbinafine is the first line treatment for what condition?

A

onychomycosis

44
Q

what are the topical antifungal classes?

A

polyenes
azoles
allylamines

45
Q

nystatin is useful against what type of infection?

A

candida

Decks in Year 2 Pharmacology Class (70):