Antifungal Chemotherapy

Question 1

What are the Dimorphic Fungi?

Answer 1

Histoplasma Capsulatum, Blastomyces dermatiditus,

Coccioides immitis, Sporothrix schenckii

Question 2

What are the opportunisic fungi?

Answer 2

Candida, aspergillus, cryptococcus

Question 3

What are the Cutaneous/subcutaneous fungi?

Answer 3

Sporothrix schenckii,

Dermadophytes: ringworm, athletes foot, onchomycosis

Question 4

What fungi are included in dermatophytes?

Answer 4

Trychophytan, Epidermophytan, Microsporum

Question 5

What are the unique targets of antifungal chemotherapy?

Answer 5

Fungal cell membrane(ergosterol and ergo synth),

Fungal cell walls (Glucan synth)

Question 6

What are the shared targets of antifungals?

Answer 6

DNA/RNA synthesis, Cell division

Question 7

What are the different classes of antifungals?

Answer 7

Polyenes, Azoles, Nucleoside analogs, echinocandins, allylamines, and microtubule inhibitors

Question 8

Which drug has the broadest spectrum of antifungal activity?

Answer 8

Amphotericin B.

Question 9

Why is Ampho B not used as much anymore?

Answer 9

Too many side effects. Replaced by azoles.

Question 10

MOA of Ampho B?

Answer 10

Binds to Ergosterol in Fungal Cell membrane.

Alters membrane Permiability.

Question 11

What are the main uses for Amphoteracin B?

Answer 11

Systemic diseases such as Candida and Cryptococcus (yeasts). and Aspergillus, Histoplasma, coccioides, blastomyces, sporothrix, and mucormycoses. (molds)

Question 12

How is Ampho B administered?

Answer 12

Insoluable in Water. Complexed with a bile salt. High protein binding!

Question 13

What are the adverse rxns of Ampho B?

Answer 13

Infusion related Rxns. Fever, chills, muscle spasms, vomiting. Decrease rate or dose of admin.
Nephrotoxicity (vasoconstrictive)

Question 14

How is toxicity of Ampho B decreased?

Answer 14

Insertion into micelles.

Question 15

What is the MOA of Azoles?

Answer 15

Inhibits ergosterol synthesis. Makes the cell membrane leaky.

Question 16

What are the two groups included in Azoles?

Answer 16

Imidazoles and Triazoles

Question 17

What types of fungi do azoles work against?

Answer 17

Pathogenic yeast, Systemic mycoses, and dermatophytes.

Question 18

How does resistance develop to azoles?

Answer 18

Less ergosterol in the fungal cell membranes.

Question 19

What are the adverse reactions to Azoles?

Answer 19

GI disturbances

Interacts with P450 in liver

Question 20

What is the 1st line treatment for systemic candida, cryptococcus, and coccidiomycosis.

Answer 20

Fluconazole

Question 21

What are the benefits of Fluconazole?

Answer 21

Less adverse effects.

Question 22

What are the pros/cons of itraconazole?

Answer 22

Broader activity than fluconazole but narrow theraputic index…

Question 23

What drug has replaced Ampho B for treating aspergillosis?

Answer 23

Voriconazole

Question 24

What fungi does Posaconazole treat?

Answer 24

Candida, Aspergillus, and mucormycoses

Question 25

What antifungal inhibits protein and nucleic acid synthesis?

Answer 25

Flucytocine

Question 26

How is flucytosine used?

Answer 26

Combo therapy for cryptococcal infections.

Question 27

What is the MOA of Echinocandins?

Answer 27

Inhibit synth of Beta-Glucans. Fungal cell wall.

Question 28

What features allow echinocandins to work on only some fungi and no humans?

Answer 28

Only works if beta-glucan present.

Question 29

Why is use of echinocandins limited?

Answer 29

Very expensive. used if no others work well.

Question 30

What drugs are administered orally (systemically) for cutaneous and mucocutaneous infection.

Answer 30

Grisofulvin and Allylamines (terbafine)

Question 31

What are the special properties of Griseofulvin and allylamines?

Answer 31

You drink it and it localizes to the Keratin containing cells.

Question 32

What is the MOA of Nystatin?

Answer 32

Ergosterol synth (like ampho B)

Question 33

What is nystatin used for?

Answer 33

Candida, local infections, oral and vaginal candidiasis.

Question 34

What is the MOA of Allylamines?

Answer 34

Disrupts Ergosterol synthesis.

Question 35

What drugs are included with topical allylamines?

Answer 35

Terbinafine, Naftifine. used for? Tinea Cruris, Tinea corporis.

Question 36

What is the first line treatment for onchomycosis?

Answer 36

Terbinafine