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Flashcards in Antifungals Deck (48)
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1

What are the 2 forms of pathogenic fungi?

Filamentous fungi and yeast

2

What characterises yeast?

Divide by budding

3

What characterises filamentous fungi?

Elongated cells divided by cell walls. Divide by spores

4

Dimorphic fungi

Appear in yeast and filamentous form depending on environmental conditions

5

5 antifungal targets

cell wall
cell membrane
protein synthesis
DNA synthesis
Mitosis

6

What is the main component of fungal cell walls?

beta 1-3 glucan

7

What is cholesterol equivalent component in the cell membrane of fungi?

ergosterol

8

What is the function of ergosterol?

Regulation of membrane permeability

9

Describe the formation of ergosterol

Squalene>squalene epoxidase>lanosterol>lanosterol 14 alpha demethylase>ergosterol

10

beta 1-3 glucan is a large polymer of what?

UDP glucose

11

What enzyme synthesises beta 1-3 glucan?

beta 1-3 glucan synthase

12

What are the 4 classes of antifungals?

Polyenes
Allylamines
Azoles
Echinocondins

13

Give 2 examples of polyenes

Amphotericine B, Nystatin (not used anymore)

14

How do polyenes work?

Form pores in ergosterol membrane resulting in loss of membrane integrity and leakage of K+

15

Give 3 of fungi that AmB treats

Aspergillus
Candida
Crytococcus

16

Adverse effects of amphotericin B

allergic reactions
Nephrotoxicity- pores form in human cell membranes

17

How is amphotericin B administered for serios/systermic infections?

Parenterally

18

How do lipid-associated Amphotericin B antifungals work?

Combining AmB to lipids minimises its delivery to kidney cells and reduces nephrotoxicity

19

In what cases is nystatin used?

Superficial infections e.g. oral/vaginal candidiasis

20

Clear cut nodule with cavity in teh middle of it. Fungus sits in the lung and causes localised infection.

Pulmonary aspergillosis

21

Example of allyamines

Terbinafine

22

What is terbinafine used for?

Athlete's foot-tinea pedis

23

How to allyalanines work?

Inhibit ergosterol synthesis

24

Is terbinafine broad spectrum or narrow spectrum?

Broad

25

Adverse effects of terbinafine?

Liver toxicity (jaundice, hepatitis)

26

Examples of dermatophyte infections that terbinafine is used to treat

Superficial fungal infections e.g. tinea pedis
Systemic use e.g. scalp ringworm, onychomosis

27

How do azoles work?

Inhibit ergosterol synthesis (lanosterol 14 alpha demethylase inhibitors)

28

Are azoles broad or narrow spectrum antifungals?

Broad

29

What antifungal is not effective against aspergillus?

Fluconazole

30

2 types of azoles

Imidazoles
Triazoles

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