Test 1 Intro to Fungal Infections Flashcards
T/F
Fungi is prokaryotic
FALSE
Fungi is eukaryotic
What is an example of a unicellular fungi?
Yeast is unicellular
What types of fungi are multicellular and produce filamentous colonies?
Mold and Mushrooms
are multicellular and form filamentous colonies
Most fungi like a pH of around ______
and a
temperature of around _______
Most fungi like acidic pH around 5.0
and a temperature of 25C
Most fungi is strictly aerobic
EXCEPT for
____________
which is aerobic AND anaerobic
**Yeast **is aerobic and anaerobic
What is the only type of fungi that is fermentative?
Yeast!
What is the main element of the growing form of molds?
Hyphae
Hyphae can be divided by cross walls called __________
Hyphae can be divided by cross walls called septa
A mold with *darkly pigmented hyphae *is called _________
Dark pigment hyphae = Dematiaceous
A mold with *non-pigmented hyphae *is called ___________
Non-pigmented hyphae = Hyaline
Molds can reproduce sexually and asexually.
___________ is used to produce sexually
while
____________ is used to produce asexually
**Fruiting Bodies/ Spores **= SEXUAL
**Conidiophores/Sporangiophores **= Asexual
Aerial hyphae form stalk-like structures when grown on media called __________
Conidiophores/Sporangiophores
for
asexual reproduction
Aerial hyphae form stalk-like structures on media that give rise to
asexual spores called _________
Conidia
asexual spores formed by Conidiophores/Sporangiophores
of Aerial Hyphae
T/F
Asexual spores, termed Conidia, are *less resistent *to
physical and chemical agents than
Hyphae
FALSE
**Conidia (asexual spores) **are MORE resistent to chemical and physical agents than Hyphae
What is a Dimorphic Fungi?
A fungi that can change from its
mycelial form into *yeast *
A dimorphic fungi is in its mycelial form at room temperature, but changes into yeast at what temperature?
37C or when in animal tissues
Blastomyces dermatitides
Coccidiodes immitis
Histoplasma capsulatum
and
Paracoccidiodes basilensis
are all examples of what?
Dimorphic Fungi
Include:
<em>Blastomyces dermatitides</em>
<em>Histoplasma capsulatum</em>
<em>Coccidiodes immitis</em>
<em>Paracoccidiodes basilensis</em>
Fungi most often reproduces in what way?
Asexually
is most common reproduction method of fungi
What are 3 mechanisms of Asexual Reproduction of Fungi?
Sporulation, Fragmentation, and Budding
Sporulation followed by germination of spores is a fungal method of asexual reproduction utilized by which two fungi?
*Aspergillus *and Penicillium
used Sporulation to reproduce asexually
Coccidiodes immitis is a fungi that utilizes what mechanism of asexual reproduction?
*Coccidiodes immitis *asexually reproduces by
Fragmentation of hyphae
Candida and Cryptococcus are forms of yeast that use what method of asexual reproduction?
*Candida *and *Cryptococcus *
reproduce asexually by
Budding of yeast cells
Fungal cells are _______ than most bacteria.
LARGER
T/F
Fungi are eukaryotic and have chloroplast
FALSE
Fungi are eukaryotic but do not have chloroplast
Fungal capsules are made of _________
Fungal capsules are made of polysaccharides
What subcellular structure of fungi aids in adherance and clumping, and can be antigenic and antiphagocytic?
Capsule!
What subcellular structure of fungi
determines *shape *and morphogenesis
and composed of microfibrils?
The Cell Wall!
What are microfibrils?
Thatchwork of polysaccharides
cross-linked with
proteins and glycoproteins
that make up the
Cell Wall of Fungi
GPI-anchored protein
Chitin
B-(1,3) glucan
B (1,6) glucan
and mannoproteins
Are found in what?
The Cell Wall of Fungi!
Composed of Chitin, B- (1,3) and (1,6) glucan, and mannoproteins
What kind of protein is commonly found on the surface of the cell wall in fungi and acts as an antigen?
Polysaccharides
Mammals have cholesterol in their cell membranes.
What do fungi have in their cytoplasmic membranes?
**Ergosterol **and Zymosterol
Polyene Antibiotics, like Amphotericin B,
target _______
instead of the mammalian cell equivalent
in order to rid the host of fungal disease.
**Polyene Antibiotics **
target fungal
Sterol
Fungal infections rarely cause disease in healthy animals.
What is the exception?
Dermatophytes
can cause disease in healthy animals
What are 10 circumstances that can give rise to
Systemic Fungal Infections?
- Prolonged administration of antibiotics
- Radiation
- Steroid therapy
- Urethane
- Mustard Gas
- Folic acid antagonists
- Cancer
- Immunosuppressive therapy or Immunodeficiency
- Cytotoxic Drugs
- Endocrine Disorders
What is the most pathogenic Fungi?
Fungi Imperfecti
is the most pathogenic
What is the one fungi that can cause
epidemics?
Dermatophytes
What are 8 factors that predispose an animal to
Fungal Invasion of Tissues
- Immunosuppression
- Prolonged antibiotic therapy
- Immunological defects
- Being young, aging, and malnutrion
- Exposure to a heavy load of fungal spores
- Traumatized tissue
- Persistent moisture on skin surface
- Neoplastic conditions
can all cause fungal invasion of tissues
Immunity to fungal infections is mainly
_____ _____
Cell-Mediated
Cell-mediated immunity to fungi
involves the constant production of antibodies which
protect from all forms of fungi EXCEPT for
Dermatophytes
are not affected by cell-mediated immunity antibodies
Most fungal infections produce
_______ lesions
that resemble mycobacteriosis
and other facultative bacterial diseases
Granulomatous Lesions
resemble
mycobacteriosis
In a fungal infection of the skin,
most animals’ immune systems do what?
Initiate hypersensitivity skin reactions
in response to fungal infection
Skin tests
are available for which
4 fungal infections?
Infections by:
- Blastomycosis*
- Histoplasmosis*
- Coccidiomycosis*
- Sporotrichosis*
What does a vet office need in order to
presumptively diagnose fungal infections?
Microscope with oil immersion lens
**10% KOH **(potassium hydroxide) in glycerol
India Ink
Hematologic Stain (Diff Quick)
Glass slides and cover slips
Atlas of Medical Mycology
The collection of
Hair, Skin, and Nails
is useful for the diagnosis of which fungi?
*Dermatophytosis *and Onchyomycosis
can be diagnosed with
Hair, Skin, and Nail specimens
When you are collecting a
biopsy for diagnosis
what container is used and
what are the two things you must collect?
Use a sterile tube with saline or water
and you must collect
Normal AND affected tissue
A **urine specimen **is especially useful
in the diagnosis of what fungi?
Collect urine to diagnose
Histoplasmosis
If you suspect
*Cryptococcus *infection,
what bodily fluid should you collect and examine?
Collect CSF to diagnose Cryptococcus
A **CSF **specimen can be used to diagnose Cryptococcus.
By using India Ink preparations
what can be observed in the cerebrospinal fluid?
Encapsulated yeasts
What do
*flakes *and *granules *indicate when found in
Pleural or Abdominal Fluid specimens?
Flakes and granules are
colonies of organisms
Transtracheal or Bronchial Washings
are useful in diagnosing
what pathogen?
Use transtracheal and bronchial washings to diagnose
Systemic mycoses
**Nasal flushings **are used to diagnose what kind of fungus or fungus related disease?
Nasal aspergillosis
and
Guttural pouch mycosis
The collection of this bodily fluid
is collected via syringe
and directly inoculated onto plated fungal media
in order to diagnose
Ocular blastomycosis
Ocular Fluid
Most fungi is grown on
Sabouraud’s Dextrose Agar
at what temperature?
20 - 25C
Fungi in the yeast phase is grown
at 37C
on what media?
Blood Agar
*Sordarins *and Azasordarins
are antifungal agents used at what site of action?
Sordarins and Azosordarins
are used to
inhibit protein synthesis
What antifungal agent is used as a
Cell Wall Inhibitor
of glucan synthesis?
Echinocandins
What antifungal agent is used as a
Cell Wall Inhibitor of
chitin synthesis?
Nikkomycin
These 2 antifungal agents are used as
Cell MEMBRANE inhibitors
of Ergosterol synthesis
Azoles
and
Allylamines
**Polyenes **are antifungal agents that cause
direct _____ ______
Polyenes cause
direct membrane damage
**Griseofulvin **is an antifungal agent
that disrupts microtubules and inhibits
what process?
Griseofulvin
inhibits
fungal mitosis
Which antifungal agent is used to inhibit
nucleic acid synthesis?
Flucytosine
inhibits nucleic acid synthesis
