Chapter 24: ID III - Antifungals & Antivirals Flashcards
What are the 3 types of fungal classification
Yeasts
molds
dimorphic
Invasive disease with Zygomycetes (Mucor species and Rhizopus species) is commonly referred to as
Mucormycosis
Which fungi are yeasts
The candida species:
- C. albicans
- C. tropicalis
- C. parapsilosis
- C. glabrata
- C. krusei
- Crypotococcus neoformans
Which fungi are molds
Aspergillus species
Zygomycetes (Mucor and Rhizopus species)
Which fungi are dimorphic
Histoplasma capsulatum
Blastomyces dermatitidis
Coccidioides immitis
What is the conventional form of Amphotericin B
Amphotericin B deoxycholate (many toxicities)
The lipid formulations of Amphotericin B are used clinically because
they have fewer toxicities (decreased infusion reactions, decreased nephrotoxicity)
Amphotericin B is active against
Yeasts: Cryptococcus neoformans
Mold: Aspergillus spp
Dimorphic fungi
Amphotericin B deoxycholate and liposomal Amphotericin B formulation
Injection
Conventional Amphotericin B for injection doses should not exceed ___ mg/kg/day d/t risk of ____
1.5 mg/kg/day
Cardiopulmonary arrest
Amphotericin B SE
Infusion-related: fever, chills, HA, malaise, rigors
Other: ↓ K & Mg, nephrotoxicity
Amphotericin B must be diluted in ___ only, & lipid formulations must be ___ during preparation
D5W
filtered
Amphotericin B deoxycholate (conventional formulation) requires ___ to reduce infusion-related reactions
Premedication with APAP or NSAID + Benadryl and/or hydrocortisone
Liposomal Amphotericin B brand name
AmBisome
Flucytosine penetrates fungal cells and is converted to
Fluorouracil
Flucytosine should not be
Used alone due to development of resistance
Flucytosine is recommended for use in combination with ____ for treatment of
Amphotericin B Invasive Cryptococcal (meningitis)
Flucytosine side effects
Myelosuppression
MOA of azole antifungals
Decreases ergosterol synthesis and cell membrane formation
Azoles are ___ of the CYP450 system
inhibitors
Fluconazole has limited efficacy against _____ due to resistance and ____ is considered fluconazole-resistant
C. glabrata
C. krusei
Fluconazole can be used for yeast infections and ____ infections
nail bed (onychomycosis)
Primary use of itraconazole
nail bed infections (onychomycosis)
What is the treatment of choice for Aspergillus
Voriconazole
Remember: V looks like upside down A
All azole antifungals can cause
Increased LFTs
Risk for QT prolongation
Many drug interactions
What is the only azole that requires renal dose adjustment
Fluconazole
Hepatotoxicity with this azole has led to liver transplantation
Ketoconazole
Which azole can cause HF
Itraconazole
Which azole can cause visual changes and phototoxicity
Voriconazole
Remember: Visual & Vori
Which azole should be taken with food
Posaconazole & itraconazole tablets and capsule
What is the IV:PO ratio for all azoles
1:1
Which azoles have SBECD vehicle
Voriconazole and posaconazole
What formulations does fluconazole come in
IV and PO
Fluconazole dose for vaginal candidiasis
150 mg PO x1
Ketoconazole oral tabs should only be used when
Other effective antifungal therapy is unavailable or not tolerated
Which 2 azoles penetrate the CNS adequately to treat fungal meningitis
Fluconazole and voriconazole
Voriconazole brand name
Vfend, Vfend IV
What should be done if a patient is going to be treated with voriconazole and CrCl < 50 mL/min
The IV vehicle accumulates, so treat with oral voriconazole
Voriconazole SE
Visual changes
↑ LFTs
↑ SCr
CNS toxicity (hallucinations)
T/F: Vfend should be taken on an empty stomach
True
Posaconazole brand name
Noxafil
T/F: Posaconazole should not be taken with food
False- take with food daily
Which azole causes QT shortening instead of prolongation
Isavuconazonium sulfate
Which azole requires a filter
Isavuconazonium sulfate
Azoles can increase the effects of which drug
Warfarin (monitor INR)
Absorption of which two azoles is pH-dependent
Itraconazole and Ketoconazole (↑ pH will ↓ absorption)
If PPIs or H2RAs must be used while on ketoconazole, what should be done
An acidic beverage (such as non-diet cola) to provide an acidic environment for absorption
Echinocandins MOA
Inhibit synthesis of beta (1,3) D-glucan, an essential component of the fungal cell wall
Echinocandins are effective against most ____ species
Candida
the word candin is in the name
Activity of Echinocandins includes
Aspergillus spp