UWorld Chapter 24: Infectious Diseases III

Yeasts

How are the following fungi classified?

Candida species

Cryptococcus neoformans

Molds

How are the following fungi classified?

Aspergillus species

Zygomycetes (Nucor and Rhizopus species)

Dimorphic

How are the following fungi classified?

Histoplasma capsulatum

Blastomyces dermatitidis

Coccidioides immitis

Amphotericin B

What antifungal binds to ergosterol, altering cell membrane permeability and causing cell death and has a very broad spectrum of activity?

Lipid

What amphotericin B formulation is a complex of the active medication and is associated with fewer toxicities, including decreased infusion reactions and nephrotoxicity?

Flucytosine

What antifungal penetrates fungal cells and is converted to fluorouracil, which competes with uracil and interferes with fungal RNA and protein synthesis but should never be used alone due to the development of resistance?

Azole

What antifungal class decreases ergosterol synthesis and cell membrane formation but are limited by significant drug interactions?

Fluconazole

What is the only azole that requires renal dose adjustments?

Ketoconazole

What Azole is associated with hepatotoxicity that has led to liver transplantation and is primarily used topically due to the toxicities and many drug interactions?

Itraconazole

What azole can cause heart failure and is primarily used for dimorphic fungi and nail bed infections (onychomycosis)?

Voriconazole

What *azole* can cause visual changes and phytotoxicity, but is the treatment of choice for *Aspergillus*?

Posaconazole

What azole should be Taken with food and has different bioavailability in suspension and tablet forms?

Fluconazole and Voriconazole

Which two azaleas inhibit CYP2C9 and, therefore, require INR monitoring when used with warfarin?

Echinocandins

What antifungal class inhibits the synthesis of beta (1,3)-D-glucan, an essential component of the fungal cell wall, but are only available as injections?

Rezafungin

What is the ONLY echinocandin that is not given once daily and is recommended in the treatment of invasive candidiasis?

Nystatin

What superficial antifungal agent can be used to treat oral candidiasis as a suspension or intestinal infections as a tablet?

Terbinafine

What superficial antifungal agent is available as a tablet or topical cream and is contraindicated in active or chronic liver disease due to causing hepatotoxicity?

Fluconazole

What is the *preferred* regimen for empiric therapy of a Candida albicans esophageal infection?

Echinocandin

What is the *preferred* regimen for empiric therapy of Candida krusei and glabrata due to higher resistance to azole antifungals as well as all candida species bloodstream infections?

Amphotericin B and Flucytosine

What is the *preferred* treatment regimen for Cryptococcus neoformans meningitis?

Terbinafine or itraconazole

What is the *preferred* treatment regimen for Dermaphytes nail bed infection?

Oseltamivir, Zanamivir, and peramivir

What drugs are neuraminidase inhibitors that reduce the amount of influenza virus in the body by inhibiting the enzyme which enables release of new viral particles from infected cells and, therefore, decrease duration of symptoms by one day and reduce complications?

48 hours

Within what time frame should neuraminidase inhibitors by started in relation to illness onset in order to be most effective?

Baloxavir

What is an endonuclease inhibitor approved for the treatment and post-exposure prevention of influenza that has the advantage of being a single dose regimen?

COVID-19

For what viral infection is nirmatralvir/ritonavir considered the preferred outpatient treatment for patients at risk of progressing to severe disease (age > 50 years, not up to date with vaccinations, immunocompromised)?

Acyclovir, Valacyclovir

What are two systemic antivirals commonly used for all herpes related diseases?

Valacyclovir

What antiviral is the prodrug of acyclovir?

One day

Within what time frame must treatment for genital herpes be initiated in relation to lesion onset?

72 hours

Within what time frame must antiviral therapy be initiated for herpes zoster (shingles) in relation to the onset of rash?