Fungal Chemotherapy

Question 0

Molds form threadlike filaments called…

Answer 0

hyphae

Question 1

If asexual budding results in an attached, what is the resulting structure called?

Answer 1

Pseudohyphae

Question 2

A mass of hyphae is called…

Answer 2

mycelium

Question 3

Fungi that exist in both yeast and mold form are called

Answer 3

dimorphic

Question 4

Hyphae on parasitic fungi are referred to as…

Answer 4

Haustoria

Question 5

Spores result from what kind of reproduction?

Answer 5

sexual

Question 6

Conidia result from what kind of reproduction?

Answer 6

assexual

Question 7

What is the fungicidal function of Amphrotericin B?

Answer 7

“Tears” holes into the cell wall by binding to ergosterol

Question 8

Why is amphotericin B largely toxic?

Answer 8

It also binds cholesterol

Question 9

Is amphotericin B used for systemic or topical fungal infections?

Answer 9

systemic

Question 10

What two types of antifungals prevent ergosterol synthesis?

Answer 10

“Onazoles” and Terbinafine

Question 11

Why do the “onazoles” not work with the brain?

Answer 11

Efflux pumps in brain

Question 12

Are the onazoles fungistatic or fungicidal?

Answer 12

static

Question 13

What human toxicity is seen in the onazoles? (four things)

Answer 13

Hepatotoxicity
neurotoxicity
interferes with hormone synthesis (don’t use in pregnancy)
drug drug interactions

Question 14

Is terbinafine fungicidal or fungistatic?

Answer 14

Cidal

Question 15

Which enzyme do the onazoles bind to in the ergosterol synthesis pathway?

Answer 15

Erg11 (p450)

Question 16

How does terbinafine work?

Answer 16

Binds to squalene epoxidase, leading to a toxic amount of squaline

Question 17

Terbinafine toxicity?

Answer 17

Use topically because interference with CYP2D6

Question 18

Flucytosine is an analogue of _____ and subsequently interferes with ___ and ___ _______.

Answer 18

5 fluorouracil, DNA and RNA synthesis

Question 19

Why is flucytosine a good antifungal choice for menningitis?

Answer 19

crosses blood brain barrier

Question 20

What is the antifungal mechanism of griseofulvin?

Answer 20

Binds to microtubules and prevents spindle formation in fungi

Question 21

Why does griseofulvin concentrate in the dead skin layers?

Answer 21

It’s lipophilic

Question 22

How is griseofulvin toxic?

Answer 22

Teratogenic

Question 23

How does caspofungin work?

Answer 23

blocks synthesis of beta-d-glucan polysaccharide

Question 24

Can caspofungin treat meningitis?

Answer 24

No. Cannot cross BBB.