Di - Micro + Immuno Exam I: Intro To Mycology

Front 1

Most fungi of medical importance are...

Back 1

saprobes or organisms that live on decaying organic matter in nature and do not require a parasitic existence in man or animals to survive.

Front 2

Are fungi Gm+ or Gm-?

Back 2

Gram+

Front 3

cell membranes of fungi contain what molecule, instead of cholesterol?

Back 3

ergosterol

Front 4

Most fungi exist in what morphological form in nature?

Back 4

hyphal form, in which they are molds, ie. consisting of branching, threadlike, tubular filaments which are collectively called mycelium.

Front 5

The two morphologic forms of fungi are what?

Back 5

1. hyphal form

2. yeast cell form

Front 6

diseases caused by fungi are called...

Back 6

Mycoses

Front 7

Mycoses (diseases caused by fungi) can be classified according to the primary site of infection. These categories are:

Back 7

1) superficial – limited to the outermost layers of the skin or hair

2) cutaneous – extend deeper into the epidermis, as well as hair or nails

3) subcutaneous – enter tissue by traumatic implantation and involve the dermis, subcutaneous tissues, muscles or fascia

4) systemic – arise from exogenous sources through inhalation of reproductive bodies of saprobic fungi and establish an initial infection in the lungs. Afterwards they may enter the blood to disseminate to other regions of the body.

5) opportunistic in which the pathogens affect only or mainly debilitated or immunosupressed hosts.

Front 8

The infectious form of most exogenous fungi which cause systemic or opportunistic infections is what?

Back 8

mold

Front 9

Infectious bodies of molds are of what two forms?

Back 9

1. conidia: spores which are present on stalk-like projections or other structures

2. arthroconidia: septal fragments of the hyphae which separate to become reproductive entities

Front 10

Topical miconazole is often effective against superficial mycoses along with other chemicals that...

Back 10

lyse keratin

Front 11

Cutaneous Mycoses may elicit a ______ _______ reaction

Back 11

delayed hypersensitivity

Front 12

tinea is used to describe what?

Back 12

Lesions caused by Cutaneous Mycoses

1) tinea capitis (scalp)

2) tinea pedis (feet; athletes foot)

3) tinea manus (hands)

4) tinea unguium (nails)

5) tinea corporis (body)

6) tinea cruris (jock itch).

Front 13

“ringworm” is caused by

Back 13

Cutaneous Mycoses

Front 14

Common subcutaneous mycoses include:

Back 14

lymphocutaneous sporotrichosis
and
chromoblastomycosis.

Front 15

Primary fungal pathogens that can cause systemic infections include:

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> Histoplasma capsulatum

> Blastomyces dermatitidis

>Paracoccidioides brasiliensis

> Coccidioides immitis

>Cryptococcus neoformans

Front 16

Why does human to human, or animal to human transmission not usually occur in systemic mycoses?

Back 16

reproductive bodies of the hyphal state (conidia or arthrospores) and not yeasts, constitute the infective bodies of systemic pathogens

Front 17

Histoplasmosis is more commonly known as what?

Back 17

“cave disease” or “spelunker’s disease”

Front 18

What pathogen is responsible for Histoplasmosis?

Back 18

Histoplasma capsulatum

Symptoms include flu-, or pneumonia-like symptoms, but after weeks or months, tuberculosis-like lesions appear which may become calcified and visible on chest x-rays. The pathogen remains viable in macrophages which serve as vectors in disseminated disease resulting in formation of granulomas in various organs.

Front 19

Blastomyces dermatitidis is the organism responsible for causing...

Back 19

Blastomycosis

Front 20

Blastomycosis is also known as what?

Back 20

“Chicago disease” or “Gilchrist’s disease”

Primary infection of lungs. Calcifications in the lungs, however, do not occur.

Front 21

Paracoccidioidomycosis is more common in what gender?

Back 21

The disease chiefly affects men (78:1 ratio, men to women) due possibly to the inhibitory action of estrogen on the hypha to yeast transition.

Front 22

“desert rheumatism” and “San Joaquin Valley fever” are names for what disease?

Back 22

Coccidioidomycosis

Front 23

Coccidioidomycosis is caused by what fungi?

Back 23

Coccidioides immitis

Front 24

The pathogen of cryptococcosis is...

Back 24

Cryptococcus neoforman, which is found in desiccated droppings of pigeons

Front 25

A characteristic feature of this organisms is that it exists only in the yeast form.

Back 25

Cryptococcus neoforman

Front 26

the major causative agent of aspergillosis is...

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Aspergillus fumigatus

Front 27

mycetomas or “fungus balls are associated with what disease?

Back 27

Aspergillosis

Front 28

This extracellular protein elaborated by A. flavus (in most cases), can contaminate foodstuff, such as peanuts, and may induce hepatocellular carcinoma.

Back 28

Aflatoxin

Front 29

It is the most common opportunistic respiratory infection in late stage HIV patients and accounts for a 10-20% mortality rate in these individuals

Back 29

Pneumocystis jirveci pneumonia

Front 30

______ in fungal cell membranes are the targets of antifungal drugs

Back 30

Ergosterols

Front 31

What are Polyenes?

Back 31

drugs which impair sterols

Front 32

Drugs which affect biosynthesis of sterols are called?

Back 32

Azole derivatives

Front 33

This agent is a Nucleoside analog, and when it is taken up by fungus, it's converted to 5-fluorouracil and then metabolized into compounds which are inhibitory to either RNA or DNA function.

Back 33

5-flurocytosine

Front 34

This agent is active against dermatophytes, but not against Candida albicans or pathogens causing systemic mycoses.

Back 34

Griseofulvin

Front 35

What does the drug caspofungin do?

Back 35

interfers with cell wall synthesis of fungi.