Antifungals Flashcards
What is the infection that sporothrix schenckii?
Cutaneous cellulitis
Where is blastomycosis usually found?
Southwest
What disease does aspergillus usually cause, and in whom?
Pulmonary disease in immunodeficient individuals
What is the leading cause of fungal meningitis?
Cryptococcus neoformans
India ink stain = ?
Cryptococcus neoformans
What are the three fungi that are responsible for onychomycosis?
Trichophyton
Epidermophyton
Microsporum
What is the chemical that fungi use in place of cholesterol in their cell membranes?
Ergosterol and ergosterol
What is the in the cell wall of fungi that makes them easier to target?
Glucans
What are the two polyenes?
Amp B
Nystatin
What are the azoles?
Ketoconazole Fluconazole Itraconazole Voriconazole Posaconazole
What is the one nucleoside analog that is used for fungal infections?
5FU
What are the three echinocandins used in fungal infections?
caspofungin
Micafungin
Anidulafungin
What are the two allylamines used for fungal infections?
Terbinafine
Naftifine
What is the one microtubule inhibitor used to treat fungal infections?
Griseofulvin
Which antifungal drugs act systemically?
Amp B
Azoles
Flucytosine
Echinocandins
Which antifungal drug has the broadest spectrum of activity?
Amp B
What is the MOA of Amp B? Is this fungicidal or fungistatic?
Binds to ergosterol in fungal cell membrane, and alters membrane permeability
fungicidal
What is the recommended treatment for disseminated fungal infections?
Amp B
What is the treatment of choice for cryptococcal meningitis?
Amp B
What are the two mycomycoses? ssx?
Rhizopus and Absidia
Infection s of sinus of DM pts and cause cerebral infx
How is Amp B resistance brought about?
membrane ergosterol concentration is decreased or if sterol target is modified
Amp B is nearly insoluble in water. How, then, is it administered IV?
Complexed with a bil salt
Which tissue can Amp B not penetrate well?
CNS
What are the major side effects of Amp B administration?
Infusion site pain, fever, chills
Nephrotoxic (d/t decreased renal perfusion)
How does encasing amp B in a lipid micelle reduce its toxicity?
the lipids have an affinity between that of fungal ergosterol and human cholesterol. This reduces non-specific binding to human cell membranes
What are the two types of azoles?
imidiazoles
Triazoles
What are the three imidazoles? What are these primarily used for now?
Ketoconazole
Miconazole
Clotrimazole
Topical infxs
What are the four triazoles?
Fluconazole
Itraconazole
Voriconazole
Posaconazole
What is the MOA of the azoles?
binds to the enzyme responsible for converting lanosterol to ergosterol, making the cell membrane leaky
What are the three major mechanisms by which resistance to azole are brought about?
- efflux pumps
- Mutations in enzymes
- Decreased ergosterol content in the membrane
What are the major side effects of ketoconazole?
High degree of p450 inhibition
Systemic toxicity
Which azole has the highest therapeutic index?
Fluconazole
What are the two major benefits of fluconazole over other azoles?
Lowest p450 interaction
can penetrate CNS
What is the agent of choice in treating candidiasis?
fluconazole
What is the agent of choice in treating cryptococcosis?
fluconazole
What is the agent of choice for treating coccidiomycosis?
Fluconazole
True or false: fluconazole is poorly water soluble
False