Mycology (complete)

Question 1

What are the two distinctive features of fungi

Answer 1

Chitin in the cell walls

Ergosterol in the membranes

Question 2

What is Dimorphism of fungi

Answer 2

their form changes with temperature
Molds at 26 degrees Celcius
Yeast at 37 degrees celcius

Question 3

What are mycoses difficult diseases to diagnose and treat

Answer 3

the signs of their diseases are missed or misinterpreted

there are few antifungal agents, and fungi are often resistant to them

Question 4

Are many mycoses contagious

Answer 4

nope, with the exception of dermatophytes, fungi found on the skin

Question 5

How are mycoses generally acquired

Answer 5

inhalation, trauma, or ingestion

Question 6

how does fungal dimorphism play into a fungus’ pathogenicity

Answer 6

in the environment, at lower temperatures, they have mycelia composed of hyphae
in the body, warmer temperatures, they exist as yeasts

Question 7

Why does it matter that fungi are yeasts when inside the body

Answer 7

because now they are invasive due to the enzymes and proteins they produce to survive in the body

Question 8

What are the three categories of fungal diseases

Answer 8

1. fungal infections
2. Toxicoses
3. Allergies

Question 9

What is a fungal infection

Answer 9

the most common fungal disease, caused by a true pathogen, or an opportunistic one, in the body

Question 10

What is a Toxicoses

Answer 10

When you eat poisonous mushrooms

Question 11

When do you get fungal allergies

Answer 11

most often results when inhalation of fungal spores occurs

Question 12

What are the four locations you can get a fungal infection

Answer 12

1. superficial - on the skin - no inflammation
2. cutaneus - on the skin, hair or nails
3. subcutaneos - below skin - traumatic injury
4. deep or systemic - in organs or bone (difficult to diagnose and treat)

Question 13

What are the 4 systemic pathogenic, dimorphic fungi

Answer 13

1. Blastomyces
2. coccidioides
3. Histoplasma
4. paracoccidioides

Question 14

How are the 4 systemic pathogens introduced into the body

Answer 14

inhalation

Question 15

where do the systemic fungal infections begin, and how do they spread

Answer 15

they begin in the lungs and spread via the blood to the rest of the body

Question 16

besides blastomyces, coccidioides, histoplasma, and paracoccidioides. how do other fungal infections occur

Answer 16

by opportunistic fungi, that are often commensals, that take advantage of weaknesses in a host’s defense

Question 17

What makes you most likely to get an opportunistic fungal infection

Answer 17

having a compromised immune system

Question 18

What is the causative agent of blastomycosis

Answer 18

blastomyces dermatitidis

Question 19

where is blastomycosis common

Answer 19

south east US and canada

Question 20

how does one contract blastomycosis

Answer 20

inhalation of dust with the fungal spores being carried into the lungs

Question 21

what is the most common type of blastomycosis

Answer 21

pulmonary blastomycosis

Question 22

What are the problems associated with pulmonary blastomycosis

Answer 22

pulmonary lesions that begin asymptomatic
granulomatus reaction with marked fibrosis
can become chronic pneumonia

Question 23

Where can pulmonary blastomycosis disseminate to

Answer 23

the skin, bone, or in males the prostate

Question 24

what can blastomycosis cause in AIDS patients

Answer 24

meningitis

Question 25

how is blastomycosis treated

Answer 25

amphotercin B

Question 26

What is the common name for coccidioidomycosis

Answer 26

valley fever

Question 27

where do you find coccidiodomycosis

Answer 27

in the southwestern US, in desert soil, mines, rodent burrows, and archealogical remains

Question 28

how does a human contract coccidiodomycosis

Answer 28

inhalation of dust that carries the arthrospores (asexual spores) into the lungs

Question 29

what is the causitive agent of valley fever

Answer 29

coccidioides immitis

Question 30

what happens to the coccidioides immitis arthrospores once in the lungs

Answer 30

they germinate into spherules that in turn produce more spores that are released into surrounding tissue

Question 31

Where do most coccidioides infections occur

Answer 31

in the lungs, pulmonary conditions

Question 32

what happens to healthy individuals who get a coccidioides infection

Answer 32

the infections resolve on their own and require no treatment

Question 33

What is the preferred drug against coccidioides infections

Answer 33

amphotercin B

Question 34

what is another name for spelunkers disease

Answer 34

histoplasmosis

Question 35

what is the causitive agent of spelunkers disease

Answer 35

histoplasma capsulatum

Question 36

Where can you find histoplasma capsulatum

Answer 36

mostly Eastern US, some in Africa and Asia

Question 37

what is the most common route of infection of histoplasma capsulatum

Answer 37

inhalation of spores into lungs

Question 38

what happens once histoplasma capsulatum gets into the lungs

Answer 38

it first attacks alveolar macrophages, then it is dispursed beyond the lungs via blood and lymph

Question 39

how problematic are most histoplasma capsulatum infections

Answer 39

they are usually asymptomatic and resolve without damage

Question 40

clinical histoplasmosis can result in one of four diseases what are they

Answer 40

chronic pulmonary histoplasmosis chronic cutaneous histoplasmosis systemic histoplasmosis ocular histoplasmosis

Question 41

what is the preferred drug against histoplasmosis

Answer 41

Amphotercin B

Question 42

What disease is the infection pattern of chronic pulmonary histoplasmosis similar to

Answer 42

TB (granulomas and latent reactivation)

Question 43

What is the causitive agent of paracoccidiodomycosis

Answer 43

paracoccidioides brasiliensis

Question 44

Where is paracoccidiodomycosis typically found

Answer 44

Mexico and south america

Question 45

who is most likely to contract paracoccidiodomycosis

Answer 45

farm workers

Question 46

what other fungal infections are similar to paracoccidiodomycosis

Answer 46

blastomycosis and coccidioidomycosis

Question 47

What is the drug of choice for paracoccidiodomycosis

Answer 47

amphotercin B or Ketoconazole

Question 48

What is the most common causitive agent of candidiasis

Answer 48

candida albicans

Question 49

What is the most common opportunistic fungal infection

Answer 49

candidiasis

Question 50

are candida part of the natural microbiota, if yes, where

Answer 50

they are common microbiota of the skin and mucus membranes

Question 51

can candida be transmitted between individuals

Answer 51

yes

Question 52

how does the dimorphism of candida differ from other fungi

Answer 52

the yeast is the commensal form, the fliamentous forms are more pathogenic

Question 53

What is the most important fungal pathogen in the oral cavity

Answer 53

candida

Question 54

What are four clinical manifestations of candida

Answer 54

Thrush diaper rash onychomycosis ocular candidiasis

Question 55

What is used to treat candidiasis

Answer 55

polyenes (nystatin, amphotercin) axoles (miconazole, clotrimazole) DNA analogues (flucytosine)

Question 56

What is the main causitive agent in cryptococcis

Answer 56

cryptococcus neoformans

Question 57

where do the spores (that cause disease when inhaled) of cryptococcus neoformans come from

Answer 57

bird droppings

Question 58

What characteristics of cryptococcus neoformans enhance its pathogenicity

Answer 58

1. its ability to resist phagocytosis which is due to a large acidic mucopolysaccharide capsule 2. predilection for the CNS

Question 59

What are the four diseases that can come from cryptococcus infection

Answer 59

1. primary pulmonary cryptococcus 2. cryptococcal meningitis 3. cryptococcoma 4. cutaneus cryptococcosis

Question 60

What are the possible outcomes of primary pulmonary cryptococcus

Answer 60

it can be asymptomatic, mild pneumonia, or develop into chronic pneumonia

Question 61

what is the most common disease that comes from a cryptococcal infection

Answer 61

cryptococcal meningitis (caused by dissemination of the fungus to the CNS)

Question 62

What is cryptococcoma?

Answer 62

a rare condition in which solid fungal masses form in cerebral hemispheres or the cerebellum

Question 63

what is the treatment for cryptococcus infection

Answer 63

synergistic combination of amphotercin B and 5-flurocytosine

Question 64

What did pneumocystis jirovenci used to be called

Answer 64

P. carnii

Question 65

pneumocystis jirovenci is a normal member of the human microbiota, when can it become problematic

Answer 65

in AIDS patients, immunosuppressed patients

Question 66

pneumocystis jirovenci can lead to pneumonia, the presence of the disease is almost diagnostic of _____

Answer 66

AIDS

Question 67

What is used to treat pneumocystis jirovenci and why

Answer 67

antiprotozoan drugs (septra), because of its similarities to protozoa

Question 68

What are the most commonly reported fungal diseases

Answer 68

superficial, cutaneous and subcutaneous mycoses

Question 69

how are superficial, cutaneous and subcutaneous mycoses acquired

Answer 69

person-to person contact or environmental exposure

Question 70

how serious are superficial, cutaneous and subcutaneous mycoses

Answer 70

they aren't usually life threatening, but can be chronic or reccuring

Question 71

do superficial mycoses illicit an immune response

Answer 71

not usually

Question 72

What is the difference between dermatophytoses and dermatomycoses

Answer 72

dermatophytoses are caused by epidermophyton, microsporum, or trichophyton dermatomycoses are caused by any other fungi

Question 73

what are dermatophytoses

Answer 73

fungal infections of the skin or nails caused by dermatophytes

Question 74

what were dermatophyte infections formerly known as

Answer 74

ringworms

Question 75

What do dermatophytes use as a nutrient source, and what does that mean for where they reside

Answer 75

they use keratin as a nutrient source, and thus only colonize dead tissue

Question 76

can dermatophytes damage living tissues

Answer 76

yes by provoking a cell-mediated immune response

Question 77

what are the three genera of ascomycetes that cause most dermatophytoses

Answer 77

trichophyton microsporum epidermophyton fluccosum

Question 78

What is the treatment for dermatophytoses

Answer 78

topical antifungal agents

Question 79

``` What are these common dermatophytoses tinea pedis tinea cruris tinea unguinum tinea corporis tinea capitis ```

Answer 79

``` tinea pedis = athletes foot tinea cruris = jock itch tinea unguinum = nails tinea corporis = body tinea capitis = scalp with hair loss ```

Question 80

What is immunity to fungi dependent on

Answer 80

activated macrophages