Antifungal (Lec 20) Flashcards
Mold vs Yeast
mold = multicell fungi yeast = single cell fungi
superficial mycoses are?
fungi of outer layer of skin/hair
cutaneous mycoses are?
fungi deeper into keratinized layer of
dermis/hair/nails
subcutaneous mycoses are?
fungi of dermis, subcut, mm and fascia
systemic mycoses from primary pathogens?
originate in lungs,
spread thru system
systemic mycoses from opportunistic pathogens?
candidiasis
aspergillosis
cryptococcosis
Antifungals mechanism?
target memb or cell wall
Amphotericin B mechanism?
interacts w/ ergosterol in memb making pores
Amphotericin B spectrum?
broad
Amphotericin B DOC for?
systemic infections
Amphotericin B administered?
IV
Amphotericin B side-effects?
nephrotoxicity due to:
infusion of drug
rxn occurring over time
Amphotericin B toxicity from infusion sxs?
flu-like
Amphotericin B toxicity over time?
cumulative azotemia (increased amounts of nitrogenous waste):
BUN and creatinine
= kidney damage
Flucytosine mechanism?
becomes 5-fluorouracil ->
θ DNA,RNA synth
Flucytosine active against?
cryptococcus neoformansº
Flucytosine DOC?
(+ amphotericin B)
cryptococcus infections
Flucytosine side-effects?
↓ bone marrow
↑ liver enzymes
Azole antifungals?
Ketoconazole (Nizoral)
Fluconazole (Diflucan)
Voriconazole (Vfend)
Itraconazole (Sporonox)
Azole mechanism?
inhibit synth of ergosterol (in memb)
Ketoconazole spectrum?
broad
Ketoconazole side-effects?
gynecomastia
drug interactions from P450 inhibition
Fluconazole penetration?
good into body fluids, esp CSF (tx meningitis)
Fluconazole side-effects?
better tolerated than other azoles
Fluconazole administered?
oral
IV
Voriconazole active against?
fungus
molds
Voriconazole DOC for?
aspergillus w/ ampho B
* ºtreatment of invasive aspergillosis
Voriconazole side-effects?
drug interactions visual impairments (reversible)
Itraconazole active against?
same as others
Itraconazole elimination?
hepatic metabolism
Echinocandin drugs?
Caspofungin
Micafungin
Anidulafungin
Echinocandins mechanism?
inhibits β(1,3)-D-glucan in cell wall
Caspofungin active against?
aspergillosis in refractory pts
Caspofungin side-effects?
mild
(P) ↑ liver enzymes
Caspofungin administration?
IV
Onychomycosis is?
Candida dermatophytes (ringworm) of the nails
Griseofluvin mechanism?
binds to keratin where:
binds microtubules of fungi ->
destroys spindle structure
Griseofluvin active against?
ringworm of skin, hair, nails
Griseofluvin DOC for?
onychomycosis
Griseofluvin length of tx?
6 mo - 1 yr
Griseofluvin side-effects?
GI
CNS
hematological
Griseofluvin contraindicated?
acute intermittent porphyria
hepatocellular failure
Terbinafine active against?
dermatophytes
Terbinafine mechanism?
interferes w/ sterol synth
Nystatin used to tx?
orally - GI candida
topically - other candida