Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Mycology (clinicals) > Mycology > Flashcards

Mycology Flashcards

1
Q

Superficial infection tissues involved

A

outer dead layer, hair, nails

Does not penetrate cell wall, does not initiate host defenses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Superficial infection representatives

A

Exophilia, Malassezia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Cutaneous infection tissues involved

A

keratinized portion of hair, skin, nails

No invasion of deeper tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Cutaneous infection representatives

A

Epidermophyton

Microsporium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Subcutaneous infection tissues involved

A

Muscle, bone, tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

SQ infection representatives

A

Sporothrix
Cladosporium
Exophilia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

systemic infections involve

A

any tissues, incl. pulmonary, lymph, circulatory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Systemic infections usually begin…

A

in the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Systemic infections usually involve ______ fungi

A

dimorphic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Systemic infection representatives

A

Histoplasma
Paracoccidioides
Blastomyces
Coccidioides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Opportunistic infection tissues involved

A

Any organ or tissue

Fungi nonpathogenic unless host becomes debilitated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Media for CNS samples

A

BHI and SABHI, with and without blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

CNS probably agent

A

Cryptococcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Media for eye samples

A

SDA, with and without antimicrobials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Eye probable agents

A

Fusarium and other opportunistic pathogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Fungemia media

A

BHIA or BHIB in biphasic bottles for specialized containers for lysis-centrifugation or automated methods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Fungemia probable agents

A

Aspergillus, Candida, Histoplasma, Torulopsis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Hair media

A

SDA with antimicrobials, DTM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

hair probable agents

A

Dermatophytes, cutaneous fungi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Media for Mucocutaneous tissue or mouth and nose (scrapings)

A

SDA and SABHI, with and without antimicrobials, and with and without blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

mucocutaneous probable agents

A

Blastomyces

paracoccidioides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

media for nail scrapings

A

SDA with antimicrobials, DTM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Nail probable agents

A

Dermatophytes

candida

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Respiratory system media (sputa, washings, biopsy tissue)

A

SDA w/ and w/o antimicrobials

SABHI w/ and w/o antimicrobials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Respiratory system probable agents

A

systemic fungi

yeast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

skin scraping media

A

SDA with antimicrobials

DTM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

skin scraping probable agents

A

dermatophytes

cutaneous fungi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

SQ lesion media (aspirates, tissue)

A

SDA w/ and w/o antimicrobials

SABHI w/ and w/o antimicrobials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

UTI media

A

SDA w/ and w/o antimicrobials

SABHI w/ and w/o antimicrobials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

SQ lesion probable agents

A

SQ fungi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

UTI probable agents

A

candida
torulopsis
Systemic fungi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Vaginal infection media

A

SDA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

vaginal infection probable agents

A

yeast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

categories for growth rate

A
  1. Rapid Growers
  2. Intermediate growers
  3. Slow Growers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Rapid grower timeframe and examples

A

<5 days

saprobes, opportunistic fungi, yeast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Intermediate grower time frame and examples

A

6 to 10 days

opportunistic fungi, dermatophytes, SQ fungi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Slow growers time frame and examples

A

> 11 days

Systemic fungi, SQ fungi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

3 problems with immunological methods to screen sera for anti-fungus antibodies

A
  1. Fungus generally not good antigens
  2. Fungus usually in one area of the body (ex. nails)
  3. Non-specific substances in pt sera (ex. CRP causes false positive test)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

How to treat mite infestations on media

A

paradichlorobenzene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

4 properties of opportunistic fungi

A
  1. Rapid growers- mature in 4 to 5 days
  2. Saprobic and airborne- feed off dead, decaying matter enriched with nitrogen
  3. Inhaled- not transmitted person to person, but by inhaling spores
  4. Opportunistic- not pathogenic unless pt becomes debilitated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Aspergillomas are…

A

balls of hyphae in lungs

Farmer’s lung

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Aspergillus fumigatus an ______ but also causes _____

A

opportunist

infection (aspergillosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

types of aspergillosis

A

colonization
allergy
disseminated infection
toxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Zygomycosis characteristics

A

zygomyces have broad hyphae- penetrate blood vessels, causes blockage, damage, tissue death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Hyalohyphomycosis caused by…

A

hyaline moulds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

phaeohyphomycosis caused be…

A

dematiaceous fungi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Dematiaceous fungi characteristics

A

Black/olive/dark

High quantity of melanin in cell walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Phaeoid

A

moulds with hyaline hyphae- dematiaceous spores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

diseases caused by dematiaceous fungi

A 
Chromoblastomycosis
Black grain mycetoma
Phaeohyphomycosis (brain abscess and cysts)
IV lines
Superficial skin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Aspergillus fumigatus characteristic morphology

A

hyphae branched at 45 degree angle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

some aspergillus sensitive to _______

A

cyclohexamide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Aspergillus fumigatus grows at ______ C

A

25 and 37

Tmax = 50 C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

charcot-leyden crystals

A

infection with aspergillus flavus, made with increased eos present
found in sputum and stool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Aspergillus flavus does not grow at ___C

A

45

Grows best at 37 C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Aspergillus niger ____ color, but not _______

A

black

not considered dematiaceous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

A. niger most often reported in _______

A

otomycosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Bipolaris often implicated in ___ and ____ infections

A

eye

nasal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

fusarium considered a _____ pathogen

A

plant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Fusarium morphology colors

A 
immature = white
mature = purple
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

significance of Penicillium marneffi

A

only pathogenic Penicillium species
Dimorphic
takes at least 2 weeks to mature
Grows at 25 to 45 C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Trichoderma has been known to cause _____ infections

A

nosocomial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Characteristics of Zygomycetes

A

Very wide pauci septate
lid lifters
Blocks blood vessels- lumen of vessels may be occluded
Rapid filament growth and rapid destruction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

5 zygomycete rapid growers

A
  1. Absidia
  2. Mucor
  3. Rhizomucor
  4. Rhizopus
  5. Syncephalastrum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Absidia rhizoids

A

present, often indistinct

also has hershey’s kiss columella and pear-shaped sporangia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Mucor rhizoids

A

none

Also: straight, long sporangiophores with some branching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Rhizomucor rhizoids

A

randomly throughout

also: columella is half-circle with flattened base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Rhizopus rhizoids

A

at base of sporangiophore

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Syncephalastrum defining characteristic

A

spores are produced in multiple tubular merosporangia that radiate from vesicles
More likely to cause onychomycosis and dermatomycosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Most common cause of rhizocerebral and pulmonary zygomycosis

A

Rhizopus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Distinguish rapid growing zygomycetes through

A

microscopic lactophenol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

All 5 rapid growing zygomecetes found worldwide in …

A

soil and decaying matter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

All rapid growing zygomecetes found in these patients ….

A

immunocompromised, debilitated, nutritionally deficient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Human zygomycete infections caused by..

A

inhalation or trauma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

2 categories of superficial infections

A

Tineas

piedras

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

piedra “stone”

A

hair infection with nodular mass of fungal elements surrounding the hair shaft
No discomfort or hair loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

2 types of piedra and agent

A

White piedra: Trichosporan beigelii

Black piedra: Piedraia horati

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Black piedra agent is a ____ whereas white is a ____

A

mould

yeast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

geographic site for black and white piedra

A

black- tropical

white- temperate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

Black piedra tissues involved

A

scalp hair, eyebrows, eyelashes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

white piedra tissues involved

A

mustache, beard, hair of axilla and groin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

Texture of black piedra nodule is ___ and white is ___

A

hard

soft

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

White piedra has ___ colored nodule and is resistant to ____.

A 
white or cream
Amphotericin B (use fluconazole)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

2 types of superficial tinea and causative agent

A

tinea nigra = Exophilia werneckii (mould)

tinea versicolor = Malassezia furfur (yeast)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

Tineas geographic site

A

nigra: tropical
versicolor: temperate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

Tinea nigra tissues involved and appearance

A

skin of hands and feet

dark macular patches that do not fluoresce

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

Tinea versocolor tissues and appearance

A

skin of chest, arms, back

skin altered from natural color, lesions may fluoresce

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

Tinea nigra growth characteristics

A

grows slowly on standard media

May start out looking like black yeast, but will eventually form olive green color and aerial mycelia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

Tinea versicolor growth

A

Yeast requires addition of fatty acids to medium

Lipolytic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

malassezia furfur known to cause systemic infections in ____ pts, esp those receiving -___

A

immunocompromised

intralipid therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

How to differentiate piedraia hortae from coccidioides immitus.

A

Piedrae fragments into arthroconidia, but lacks disjuncture cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

trichosporan beiglii forms these structures:

A

hyaline septate hyphae and arthroconidia
Blastoconidia

(yeast-like colonies at 25 C, hyphae and pseudohyphae start to form)

92
Q

Media that provides classic pigment and morphology. Poor recovery for dermatophytes. Good for yeast.

A

Sabouraud dextrose agar (SDA)

93
Q

Media that enhances the production of reproductive structures and colony color, promotes sporulation

A

Potato Dextrose agar/Potato flake agar

PDA/PFA

94
Q

ideal media for slide culture

A

PDA

95
Q

enrichment media for recovery of yeasts (esp Cryptococcus neoformans)

A

BHI

96
Q

media that enhances the growth of fastidious dimorphs and used for mould-yeast conversion

A

BHI

97
Q

Benefit of SABHI media

A

ingredients of both SDA and BHI

enriched for recovery of yeasts

98
Q

Inhibitory mold agar

A

Enriched media that provides better recovery of fastidious fungi.
May/not contain chloramphenicol or gentamicin

99
Q

Mycobiotic agar (Mycocel) contains ______ to inhibit _____ and ______ to inhibit _____

A

chloramphenicol, bacteria

cyclohexamide, saprobic fungi

100
Q

disadvantages of mycocel media

A

true pathogens can sometimes be inhibited by cyclohexamide

chloramphenicol-resistant bacteria may be able to grow

101
Q

dermatophyte test medium contains: (3 things)

A

antibiotics
cyclohexamide
pH indicator

102
Q

what turns DTM red?

A

Dermatophytes (white, fluffy)
yeast
Alternaria (brown colonies)

103
Q

Bacteria and saprobes turn DTM ____

A

yellow

104
Q

CHROMagar candida contains ____ to inhibit bacteria and differentiates yeast by…

A

chloramphenicol

Turning different colors for different yeast species (good for mixed cultures)

105
Q

Yeast Extract Phosphate medium (YXP) is selective for ______. Addition of _______ to surface will inhibit yeast

A

dimorphic fungi

Concentrated ammonium hydroxide

106
Q

2 things accomplished by Cornmeal agar or Rice Agar with Tween 80 and cornmeal glucose

A

Produces chlamydoconidium formation in C. albicans

Pigment production in Trichophyton rubrum (red)

107
Q

Purpose of Caffeic acid (bird seed/niger) agar

A

detection of Cryptococcus neoformans (turns black)

108
Q

cyclohexamide use and precaution

A

Prevents overgrowth of slowly growing moulds from others that grow faster
May inhibit some pathogens (Aspergillus fumigatus, C. neoformans, Pseudallescheria boydii, Candida krusei, Trichosporan)

109
Q

KOH works by…..

A

dissolving keratin (strong alkaline solution), making fungal elements more visible

110
Q

KOH combined with _____ is more sensitive, but requires the use of ________ ________

A

Calcoflour white

Fluorescent microscope

111
Q

Calcoflour works by….

A

binding polysaccharides cellulose and chitin, fluoresces when exposed to UV light

112
Q

4 components of Latophenol Cotton Blue and what they do

A

1) Lactic Acid: cleaning agent and aids in preserving fungal structures
2) Phenol: killing agent
3) Glycerol: Prevents drying
4) Cotton Blue: Gives color to structures

113
Q

LCB stain is used as both a _____ and a ____

A 
mounting fluid (tease mount or cellophane tape mount)
stain
114
Q

Saline wet mount usually used for…

A

direct exam for presence of yeasts

115
Q

Gram stain used for….

A

examining specimens for presence of aerobic actinomycetes

116
Q

acid fast stain is used for… (3 things)

A

nocardia (partially acid fast staining pink)
ascospores in yeast (stain blue)
Vegetative cells (stain pink)

117
Q

India Ink is used for…

A

observing CSF for Cryptococcus neoformans/gattii.

118
Q

C. neoformans is detected by (2 methods)

A

capsular halo when india ink stain used

direct antigen tests

119
Q

Wrights/Giemsa stain may be used for….

A

detecting intracellular yeast forms of Histoplasma capsulatum in blood and BM

120
Q

Methenamine silver nitrate is considered most useful ____ method because it provides better ____ than other methods

A

screening

contrast

121
Q

GMS stain, fungus stains ____ against _____

A

black against a pale green background

122
Q

Slide culture method is the best for…

A

preserving and observing the actual structure of a fungus

123
Q

dermatophytes definition

A

a fungus that invades the keratinized portion of the hair, skin, and nails

124
Q

dermatophytosis

A

mycotic infection of hair, skin and nails

125
Q

Dermatomycosis

A

invasion of cutaneous tissue by other fungi (not dermatophytosis)

126
Q

Athrophilic

A

People-loving

Epidermophyton

127
Q

Geophilic

A

earth-loving

Microsporium

128
Q

Zoophilic

A

Animal loving

Microsporium, Trichophyton

129
Q

5 things to consider if suspecting a dermatophyte

A
  1. Source
  2. Presence of Microconidia
  3. Macroconidia (# and shape)
  4. Teleomorph?
  5. Fluroscence
130
Q

“5 things” regarding Epidermophyton

A
  1. Skin, nails
  2. no microconidia
  3. smooth, thin-walled, sparse macroconidia
  4. Teleomorph N/A
  5. no fluorescence
131
Q

“5 things: regarding Microsporium

A
  1. hair, skin
  2. Few microconidia
  3. thick, rough-walled, numerous macroconidia
  4. Teleomorph = arthroderma
  5. Fluroscence characteristic of some species
132
Q

“5 things” about Trichophyton

A
  1. Hair, skin, nails
  2. Many microconidia
  3. Smooth, thin-walled, few macroconidia
  4. Teleomorph = arthroderma
  5. No fluorescence
133
Q

Ring worm

A

Dermatophyte infection

Fungus spreads in circular pattern on skin, outer edge alive and sreading

134
Q

Tinea capitis

A

scalp and hair

135
Q

Tinea barbae

A

facial hair and beard

136
Q

Tinea corporis

A

body

137
Q

Tinea cruris

A

groin

138
Q

tinea pedis

A

foot

139
Q

Tinea unguium

A

nails

associated with onychomycoses, also happens from other types of fungus (aspergillus, candida)

140
Q

Tinea manuum

A

hands

141
Q

Dermatophyte disease state

A

Tinea

142
Q

Ectothrix

A

ability of fungus to grow outside of hair shaft, may resolve on its own

143
Q

Endothrix

A

ability of fungus to grow and penetrate into the hair shaft

Can become chronic, would need to treat with systemic meds

144
Q

Hair perforation test looks for….

A

Trichophyton mentagrophytes

145
Q

4 test methods for dermatophytes

A
  1. Woods lamp (Microsporium- bright yellow/green, others don’t fluoresce)
  2. Microscopic exam with KOH (10% for hair and skin, 20% for nails)
  3. DTM (phenyl red indicator changes media to red with increased pH)
  4. PDA (inhibits bacteria)
146
Q

Mycetomas

A

chronic granulomatous infection typically on the extremities

SQ

147
Q

Sporotrichosis

A

“Rose gardener’s disease’
Caused by sporothrix schenckii
Chronic infection characterized by nodular lesions of the cutaneous or SQ tissues and adjacent lymphatics that suppurate, ulcerate, and drain.

148
Q

Chromoblastomycosis

A

Characterized by verrucoid crusted nodules (SQ)

149
Q

Phaeohyphomycosis

A

Infection caused by dematiaceous fungi (SQ)

150
Q

3 phaeohyphomycoses

A

Mycetoma
Sporotrichosis
Chromoblastomycosis

151
Q

types of candidiasis

A 
Thrush
Vaginosis
balanitis
paronychia
Any organ system (UTI, septicemia, meningitis, endocarditis)
152
Q

Yeast vs, yeast-like distinction

A

True yeasts are a perfect fungus that reproduces sexually and asexually
Yeast-like organisms only reproduce asexually

153
Q

Germ tube

A

parallel sides
non-septate
no constriction at point of attachment
(99% Germ tube positive yeast are C. albicans)

154
Q

Pseudohyphae

A

not necessarily parallel
May be septate
Constricted at point of attachment (sausage-shaped)

155
Q

Most frequently encountered fungal opportunist

A

C. albicans

156
Q

Characteristics of C. albicans

A 
germ tubes formed within 3 hours at 35 C
both blastoconidia and pseudohyphae present
Carbohydrate utilization
no capsule
cyclohexamide resistant
157
Q

Newest yeast of concern

A

candida auris

hard to kill, resistant to many antifungals, septicemia

158
Q

yeast associated with pigeon droppings

A

cryptococcus neoformans

159
Q

Most common form of cryptococcus infection and specimen

A

Meningitis (esp in immunocompromised), CSF

160
Q

Advantages and disadvantages of cryptococcal latex agglutination test

A

Rapid, good for titers

not sensitive, patients with RA or disseminated Trichosporan beigleii infections can cross-react. Would need to boil specimens with Na2EDTA or treat serum with pronase

161
Q

Cryptococcal cells are surrounded by….

A

refractile mucopolysaccharide capsule

162
Q

2 ways to differentiate cryptococcus from candida

A
  1. Niger seed agar (crypto has melanin)

2. urease slant (Crypto is urea Pos, observe for 4 days_

163
Q

I both crypto and candida infections…..

A

Spinal fluid will have decreased glucose, increased protein, and lymphs will predominate

164
Q

this yeast used to be considered a parasite

A

pneumocystic carinii

165
Q

Rhodotorula species significance

A

Increasing infections, found in lungs and UTIs and endocarditis, meningitis, mycotic keratitis, peritonitis

166
Q

Rhodotorula characteristic

A

Red, coral, orange colored colonies

167
Q

Dimorphs as systemic fungi

A

A mold that is inhaled at 30 to 35 C and then becomes a yeast in the body at 37 C

168
Q

Conversion of dimorphs in the lab is achieved by:

A

using fresh BHI agar containing 5 to 10% sheeps blood

169
Q

cottonseed conversion media used for:

Pros and cons:

A

Blasto
Pros; enhances recovery of fungus, speeds growth
cons: Blood based media will decrease sporulation

170
Q

Blastomyces dermatitidis endemic to:

A

North America, surrounding areas of Mississippi, Missouri, and Ohio River Valley

171
Q

2 names for blasto infection

A

Chicago’s Disease

Gilchrist Disease

172
Q

Blasto found in these environments

A

moist

wood, tree bark, rotting vegetation, manure, leaves, river banks

173
Q

Blastomycosis Infection:

A

A chronic granulomatous and suppurative disease that may affect lungs, skin, mucosal membranes, and other organ systems

174
Q

Chronic cutaneous blasto;

A

with or w/o lung involvement
verrucous and ulcerated with small abscesses that suppurate and weep
Can spread without treatment

175
Q

Blast specimen

A 
sputum or other pulmonary
pus aspirated from lymph node
SQ abscesses
skin scrapings or biopsies from ulcers
21 to 146 day incubation
176
Q

Blasto antigens

A

A and B

A more sensitive and specific, Blastomycin (extract of the yeast form), Can be used for skin testing

177
Q

4 types of blasto immunology tests

A
  1. FA test (fluorescent)
  2. ID test (used purified yeast antigen, reference sera)
  3. Serological test- EIA (can cross react with Histoplasma, best method)
  4. specific A-band exoantigen test
178
Q

Blasto macroscopic morphology

A

25 C: On modified SABS, mature colonies grow in 6 to 21 days, first colonies are waxy, white/beige and then become fluffy

37 C: on BHI with blood yeasts will appear at 10 to 15 days with wrinkled or folded waxy texture, look dry.

179
Q

Blasta microscopic morphology

A

25-30 C: fine hyphae, septate and hyaline. Conidia are directly on hyphae or on conidiophores, resemble lollipops

37 C: mother cell attached to daughter by broad base, highly refractile around edges

180
Q

Blasto tissue reactions evoke…

A

a suppurative, granulomatous response

neutrophils predominate until it ages

181
Q

Blasto decreased tissue phase response and…

A

abscesses form a cavity/granuloma that is only detected by X-ray (or DNA probes, exoantigen)

182
Q

Coccidioides immitis endemic to:

A

hot and dry areas, alkaline soil with high salt content-

zones of northern mexico and pacific coast of Midwest

183
Q

Names for coccidioides infections;

A

Valley Fever

california’s disease

184
Q

Most virulent of all human mycoses:

A

Coccidioides immitis

185
Q

Coccidioides immitis presents increased infection risk to:

A

Construction workers, farmers, increased rate of lab acquired infections

186
Q

2 common Coccidioides infections:

A
  1. primary pulmonary (asymptomatic, self-limiting)

2. meningitis

187
Q

Primary pulmonary Coccidioides more common in ___ than ___.

Dissemination rate….

A

Women, men

Dissemination rate 4X higher in men

188
Q

characteristics of primary pulmonary coccidioides

A

skin eruptions with erythema and nodosum, erythema multiforme may develop.
usually self-limiting, 60% resolve w/o tx

189
Q

Most common cause of Coccidioides infection death

A

meningitis

190
Q

Coccidioides specimen sources

A

sputum, pulmonary specimens, aspirated pus, skin scrapings, CSF, blood, urine

191
Q

Coccidioides immunology uses these 2 antigens:

A
  1. Coccidioidin (filtrate prepared from mould cultures)
  2. Spherulin (extract from a tissue culture of the yeast form)

Individual antigens have not been characterized

192
Q

Either coccidioidin or spherulin could be used as the…

A

antigen in coccidioides complement fixation (CF) test

193
Q

Coccodioides tests

A

DNA probes, exoantigen tests, FA tests

194
Q

Coccidioides temperature considerations

A

25-35 C: Mould form
37-40 C and increased CO2; tissue phase
(Tmax = 54 C)

195
Q

Coccidioide immitis Macroscopic

A

arthroconidia will form in 7 to 10 days, giving the colonies a powdery tecture

196
Q

C. immitis microscopic (mould phase)

A

septate hyaline hyphae
Arthroconidia usually single celled and barrel shaped
alternating disjuncture cells
Raquet hyphae seen in young cultures

197
Q

C. immitis microscopic tissue phase

A

large, round, tick-walled structures that contain infectious endospores

198
Q

Histoplasma capsulatum endemic to:

A

central-north America, river valleys: Ohio, Mississippi, Missouri

199
Q

Names for Histoplasma capsulatum disease

A

Darling’s disease
Cave fever
Spelunker’s disease

200
Q

H. capsulatum associated with…

A

soil with increased nitrogen from deposits of chickens, bats, birds (starlings)

201
Q

H. capsulatum transmission

A

airborne, highly infectious

202
Q

histoplasmosis

A

Chronic granulomatous disease that involves the lungs and RE system

203
Q

Main characteristic of Histoplasma infection

A 
coin lesions (seen in X-rays;
Fibrosis around the cavities in the lungs causing flat, round areas)
204
Q

Fibrosing medastinitis

A

You had the disease, it’s treated and cured, but still have disease progression due to scar tissue

205
Q

Histoplasma capsulatum specimens

A

sputum and other pulmonary, lymph nodes, SQ abscesses, skin scrapings and other tissues

206
Q

H. capsulatum detection methods

A 
complement fixation (sensitive but not specific)
Titers (appear within 2 to 3 weeks of exposure)
207
Q

histoplasma macroscopic

A

25 C: SABS agar, matures in 15 to 25 days
37 C: BHI with blood, colonies in 10-15 days
(slow growing)

208
Q

histoplasma mould microscopic

A

some isolates do not sporulate

macroconidia- unicellular, spherical or pyriform shapes, become tubular as they age (Sunflowers0

209
Q

histoplasma tissue phase microscopic

A

Small, round oval yeast

Found primarily in macrophages by GMS, PAS, H&E stains

210
Q

histoplasma infections invoke a …

A

lymphocyte response

211
Q

Paracoccidioides brasiliensis is AKA

A

South American blasto

212
Q

p. brasiliensis infection transmission:

A

highly infectious, airborne transmission via contaminated plants

213
Q

Most common form of p. brasiliensis infection

A

Pulmonary Paracoccidioides, asymptomatic and self-limiting

214
Q

Paracoccidioides secondary infections…

A

usually occur on the face, mucous membranes, nose, mouth, throat

215
Q

P. brasiliensis specimens

A

sputum, respiratory, skin scrapings

216
Q

Methods of detecting P. brasiliensis

A

complement testing with Immune diffusion (98% specificity if you have symptoms)
Direct FA testing

217
Q

P. brasiliensis at 25 and 37 C

A

25 on SABS: 2-3 week incubation, very tiny and hard to see, mould form has oval conidia with truncate bases

37: yeast-like colonies in 10-15 days
Tissue phase: Mariner’s wheel

218
Q

single conidia at ends of hyphae or conidiophores

A

blasto mould form

219
Q

broad based budding yeast

A

blasto tissue phase

220
Q

Alternating arthroconidia with disjuncture cells

A

coccidioides at room temp

221
Q

spherical endospores

A

Coccidioides tissue phase

222
Q

macroconidia with fin0like tuberculate edges

A

histoplasma at RT

223
Q

Intracellular, small round budding yeast

A

histoplasma tissue phase

224
Q

Hyphae with terminal and intercalary conidiophores

A

Paracoccidioides

225
Q

Mariner’s wheel

A

Paracoccidioides tissue phase

Mycology (clinicals) (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions