Medical Mycology

Question 1

What are fungi?

Answer 1

Have true nuclei
Have cell walls
Produces spores

Question 2

Four classes of fungi

Answer 2

Fungi imperti
Basidiomycetes
Zygomycetes
Ascomycetes

Question 3

Types of fungi infections

Answer 3

Systemic
Subcutaneous
Cutaneous

Question 4

Describe the capsule in fungi?

Answer 4

Made of poysaccharides, functions are antiphagotic,

Question 5

Example of a fungi that has a capsule?

Answer 5

Cryptococcus neoforman

Question 6

Describe cell wall in fungi

Answer 6

Multilayered , polysaccharides ( hexosomes and hexosamine)
Protein and glycoproteins
Antigenic in nature

Question 7

Function of cell wall

Answer 7

Provides shape, rigidity, strength and protection from osmotic shock.

Question 8

Chitin is the polymer what is the monomer

Answer 8

N-acetyl glucosamine

Question 9

Chitosan monomer

Answer 9

D- glucosamine

Question 10

Cellulose, alpha and beta glucan

Answer 10

D glucose

Question 11

Mannan

Answer 11

D- mannose

Question 12

Sterols in fungi

Answer 12

Ergosterol and zymosterol

Question 13

What makes fungi pathogenic?

Answer 13

Thermotolerance
Ability to survive in tissue Environment
Ability to withstand host defenses ( antiphagotic , large hyphe, professes and elastase facilitate invasion)

Question 14

Yeast

Answer 14

Unicellular
Oval to round
Bud is called a blastomere
Pseudo hyphae
Pasty colonies

Question 15

Moulds

Answer 15

Multicellular
Hyphae
Shape and morphology ( racquet, nodular, spiral, rhizoids, chandelier)

Question 16

What is dimorphic?

Answer 16

Having a yeast phase and a Mycelial form under different conditions

Question 17

Yeast form

Answer 17

Parasitic form
Tissue form
Cultured at 37 degrees

Question 18

Mycelial form

Answer 18

Saprophytic form

Cultured at 25 degrees

Question 19

What are spores?

Answer 19

A reproductive propagule that forms either following meiosis or asexually by a cleavage process.

Question 20

Asexual reproduction

Answer 20

Athrospores
Blastospore
Chlamydospore
Conida microconidia or microconidia

Question 21

Sexual

Answer 21

Zygospore
Ascospore
Basidiospore

Question 22

Para sexual reproduction

Answer 22

Genetic exchange

Question 23

Pityriasis vericolor is caused by ……….. and identification of this fungi

Answer 23

Malassezia furfur ….. spaghetti and meatballs

Question 24

White piedra is caused by ……….. and identification of this fungi

Answer 24

Trichosporum beigelii ……. White nodules on hair shaft of mycelia that fragments into arthrospores.

Question 25

Black piedra is caused by ........... and identification of this fungi

Answer 25

Piedra hortai ........ Black nodules on hair

Question 26

Tinea nigra is caused by ........... and identification of this fungi

Answer 26

Hortaea werneckii

Question 27

Cutaneous mycoses are mainly caused by

Answer 27

Dermatophytes

Question 28

Tinea unguium

Answer 28

Nail

Question 29

Tinea pedis aka athlete foot

Answer 29

Foot

Question 30

Endothrix

Answer 30

Hair shaft interior

Question 31

Ectothrix

Answer 31

Hair shaft surface

Question 32

Tines cruris

Answer 32

Jock , groin

Question 33

Cutaneous infections are caused by

Answer 33

Trichophyton sp, epidermphyton sp

Question 34

Subcutaneous

Answer 34

Confined to subcutaneous tissue and rarely spread to systemic. Soil organism into extremities by trauma.

Question 35

Sporotrichosis is caused by

Answer 35

Sporothrix schenckii ........ Rosette pattern on culture At 25

Question 36

Symptoms of sporotrichosis

Answer 36

Nodules and ulcers along lymphatics at the site of inoculation

Question 37

Chromoblastomycosis caused by

Answer 37

Fonsecacea pedroso, compacta , wangiella dermatitdis....... Copper color balls called medlar bodies in tissues

Question 38

Warty nodules that progress to cauliflower like appearance at site if inoculation

Answer 38

Chromoblastomycosis

Question 39

Mycetoma is caused by

Answer 39

Pseudallescheria boydii, madurella grisea, madurella mycetomatis

Question 40

Mycetoma symptoms

Answer 40

Draining sinus at site of inoculation

Question 41

Systemic infection

Answer 41

Involve skin and deep viscera Maybe widely disseminated Predilection for specific organs

Question 42

Histoplasma capsulatum

Answer 42

``` Dimorphic Tuberculate microconidia (sunflower) ```

Question 43

Paracoccidiodes brasiliensis

Answer 43

Ship wheel ,

Question 44

Blastomyces dermatitidis

Answer 44

Yeast cells are medium size with thick walls

Question 45

Coccidiodes imitis

Answer 45

Spherules are multinucleated

Question 46

Cryptococcosis neoformans

Answer 46

Only fungi with a capsule .

Question 47

Candidiasis is caused by

Answer 47

Candidasis

Question 48

Aspergillosis is caused by

Answer 48

Apergillus fumigatus

Question 49

Zygomycosis is caused by

Answer 49

Rhizopus sp, absidia sp, mucor sp

Question 50

Diagnosis of systemic

Answer 50

Culture Histology Serologic alp testing Molecular

Question 51

Cryptococcosis is tested by

Answer 51

Latex agglutination for antigen

Question 52

Aspergillosis tested

Answer 52

EIA for galactomannan antigen

Question 53

Laboratory diagnosis

Answer 53

Gram stain, KOH, India ink or calcofluor white Culture , SDA, mycobiotic agar Serology

Question 54

Polyene drugs attack

Answer 54

Ergesterol

Question 55

Examples of polyene derivatives

Answer 55

Amphotericin B, nyastain

Question 56

Azolesinhibitthe synthesis of ergosterol blocking the action of 14 alpha demethylase

Answer 56

``` Ketoconazole Fluconazole Itraconazole Voriconazole Posaconazole ```

Question 57

Mechanisms of amphorericin B

Answer 57

Binds to sterols, has a greater avidity for ergosterol , binding to fungal cell alters the permeablity and intracellular contents to leak

Question 58

Griseofulvin

Answer 58

Skin and nails

Question 59

5- fluorocytosine

Answer 59

Inhibits DNA synthesis

Question 60

Allylamines

Answer 60

Terbinafine ( lamas ill)

Question 61

Echinocandins

Answer 61

Inhibit the synthesis of beta-d- glucan in fungal cell wall