FUNGUS

Question 1

Whats the materials in fungi cell wall and cell membrane

• whats the biochemistry behind it
• drugs
• give all drug classes + that one

Answer 1

Cell Wall chitin + beta 1,3 glucan
Cell membrane: ergosterol instead of cholesterol

beta 1,3 glucan synthase; inhibited by Echinocandins
Ergosterol made by
- Squalene Epoxidase from Squalene to Lanosterol
– blocked by Terbinafine
- C14, alpha demethylase from Lanosterol to Ergosterol
– blocked by Azoles

• polyenes - AmG and Nyastatin
• • bind to ergosterol and form HOLES
• metroniadazole - for parasites lmao
• • nitrogen receives electron, reduced to form free radicals to fuck shit up;

Question 2

Azoles

• MOA
• names
• AEs for both
• DDI
• Contra I

Answer 2

Azoles

• triazoles (cutaneous, systemic)
• imiazoles (superficial)
• Inhibit C14 Alpha demethylase
  DDI: Inhibit CYP

Triazoles - Oral, IV - RENAL

• Fluconazole - Oral VVC;
• Itraconazole - Cardiotoxic - Bad CSF
• Vorinazole - Neurotoxic - First line aspergillus

AE

• GI; N&V
• QTc
• Hepatotoxicity;

PREGNANT CANNOT;

Imiazole - TOPICAL

• Clotrimazole - VVC
• Miconazole

Contact dermatitis; vulva irritation

Question 3

Polyenes

Answer 3

Binds ergosterol form pores

Amphotericin B

• poor bioavailability;
• IV infusion - conventional and Liposomal
• Liposomal less renal damage, more expensive, better CSF

AE

• BMS
• Infusion - thrombophlebitis, Fever and Chills
• Nephrotoxicity of conventional
• Ototoxicity

Nyastatin - oral thrush, vaginal; swish and spit
- combine w Amp B for candida

AE
- irritation

Question 4

Gimme 3 treatment of VVC

Answer 4

Oral Fluconazole
Topical Clotrimazole

Nystatin

Question 5

Terbinafine

• MOA
• ROA
• Use
• DDI

Answer 5

• Only good oral bioavailability cutaneous drug

Oral, Topical
- Block Squalene Epoxidase

• Tinea and Onychomycosis
• Inhibit CYP450

Question 6

Echinocandins

MOA
ROA, ROE
USeS

AE

Answer 6

Systemic, IV, Liver

Block beta 1,3 synthase for beta 1,3 glucan in CELL WALL
- Caspofungin, Micafungin

Systemic:
Gold standard for crytococcus (bad for CSF tho)
- Echinocandin + AmB

First line for candida

AE:

• IV: infusion: Fever, chills, rash, phlebitis
• GIT

Question 7

First line Cryptococcus neoformans

Answer 7

AmB (plus 5FC), Echinocandins

Question 8

First line aspergillus

Answer 8

Voriconazole, Amb, Echnino

Question 9

First line candida

Answer 9

Echinocandins;

Question 10

5 FC

MOA

ROA
How to Use

Answer 10

5-Flucytosine

1st - fungal cytosine deaminase to 5FU

2a FU to fUTP - block protein synthesis; RNA
2b FU to fDUMP
– fDUMP inhibits thymidylate synthase

Systemic
Oral Renal

• must use in combi; AmB for crypt, candi

AE

• BMS (same as AmB)
• GI, hepatotoxicity

Question 11

Which antifungals has BMS
Which antifungals has CYP inhibitory
Which systemic antifungals has infusion toxicity

Answer 11

AmB and 5FC - used together
Azoles and Echinocandin
IV: AmB and echinocandins (not triazoles)

Question 12

Whats metroniazadole

MOA
ROA, ROE
Uses
- contrast w clindamycin

Answer 12

Anti-parasitic, Anti-bacterial

Oral, LIVER metab, RENAL

• Nitrogen group receives electron, reduced to give free radicals
• reducing environment anaerobe
• Anaerobe - CDAD, bacteriodes ; oral vancomycin can also
• Amoeba
• H. Pylori triple therapy
• • Amoxicillin, Clarithromycin/Metroniadazole, Omeprazole 2 weeks

Clindamycin also Anaerobes ONLY, gram pos
- oppositie of Aztreonam gram neg aerobes
BUT Clostridium Diff - Gram Pos Anaerobe not hit by clindamycin
- hence metroniazadole for this anaerobe

Question 13

Metronidazole

AE

Answer 13

GI

- metallic taste in your mouth.

Question 14

Which antifungal cannot for pregnancy

Answer 14

Triazoles

Question 15

Cryptococcal meningitis give what

Answer 15

AmB + 5 FC

Question 16

Which antifungals poor CSF

Answer 16

Itraconazole
Echinocandins (long name)

Question 17

Note itraconazole better w low pH avoid in PPI

Answer 17

ok