Fungal Infection Flashcards
(164 cards)
1
Q
fungi: eukaryotic/prokaryotic?
A
eukaryotic
2
Q
diverse group of chemoheterotrophs
A
Fungi
3
Q
T/F fungi are saprophytic and lack chlorophyll
A
T
4
Q
means that an organism depends on dead or decomposing matter
A
saprophytic
5
Q
T/F most fungi are facultative aerobes, many requireing moisture for growth
A
F most fungi are OBLIGATE aerobes, many requireing moisture for growth
6
Q
fungi: multicellular filaments
A
mold
7
Q
fungi: individual cells alone or in chains
A
yeast
8
Q
consists of hyphae that grow and divide at their tips
A
mold
9
Q
threadlike filaments
A
hyphae
10
Q
round cells produced by mold that easily become airborne –> infection through inhalation
A
conidia
11
Q
vegetative part of a fungus or fungus-like bacterial colony
A
mycelia
12
Q
multicellular filaments form __
A
mycelia
13
Q
long strands of tubular structure
A
hyphae
14
Q
mold or yeast: aspergillus flavus
A
mold
15
Q
basic body plan of the fungus
A
hyphae
16
Q
network collection or bundle of hyphae in one single place
A
mycelium
17
Q
difference of hyphae and mycelium (visibility)
A
mycelium is visible to the naked eye
18
Q
single or chains of vegetative cells forming bacteria-like colony without aerial hyphae
A
yeast
19
Q
yeast: reproduction
A
most by budding
20
Q
Yeast: formed when chains of elongated cells fail to detach during budding
A
pseudohyphae
21
Q
most medically important fungi which can cause disease
A
dimorphic fungi
22
Q
exist as yeast or molds depending on environment conditions specifically the temperature
A
dimorphic fungi
23
Q
dimorphic:
human body temp?
room temp?
A
body temp: yeast
room temp: mold
24
Q
what are the cell walls of fungi made of?
A
chitin
some contain ergosterol in the cell membranes
25
what are ergosterol? function? clinical importance?
same function that cholesterol does in animals
some anti-fungal drugs target ergosterol by inhibiting its synthesis or binding to it to induce fungal death
26
involved in catabolism and growth
vegetative structures
27
tubuluar filaments of cells/hyphae
thallus
28
type of hyphae according to pigmentation
1. hyaline
| 2. dematiaceous
29
type of hyphae according to septation
1. septate
| 2. aseptate/coenocytic
30
non-pigmented or brightly pigmented hyphae
hyaline
31
darkly pigmented hyphae
dematiaceous
32
reason why there's a dark pigmentation in dematiaceous hyphae
presence of melanin
33
best stain for dematiaceous hyphae
Fontana-Masson stain
34
cross walls divide them into unicellular units
septate
35
allow cytoplasm and nuclei to pass in septate hyphae
pores
36
no septa; continuous cell with many nuclei
aseptate/coenocytic
37
t/f all fungi are chemoheterotrophs (nutrition)
T
38
chemoheterotrophs v chemoautotrophs
chemoheterotrophs are unable to synthesize their own organic molecules
they ingest preformed carbon molecules (carbohydrates and lipids) synthesized by other organism in environment
39
absorption of nutrients
powerful exoenzymes
40
T/F fungi grow at higher pH than bacteria
F
| fungi grow at LOWER pH than bacteria
41
fungi best grow at...
lower pH
| high salt and sugar
42
fungi that produce mycelia (molds)
filamentous fungi
43
reproduction: filamentous fungi
asexually by fragmentation of hyphae
| asexual and sexual reproduction of spores
44
reproduction: yeast
asexually by BUDDING or FISSION
SEXUAL reproduction by spores (compared to filamentous which is asexual and sexual)
but asexual (budding/fission) is still more common than sexual.
45
associated with roots of vascular plants-truffles and oak --> assist in absorption of water and minerals
Mycorrhizae
46
advantages of fungi
```
mycorrhizae
decompose dead org
recycle nutrietnts
control pests
food (bread) and antibiotics (penicillin)
```
47
disadvatages of fungi
fungal diseases
48
human disease caused by fungi
mycoses
49
four major types of mycoses
superficial and cutaneous mycoses
subcutaneous mycoses
endemic mycoses
opportunistic mycoses
50
mycoses: common and limited to the very superficial or keratinized layers of skin, hair, nails
superficial and cutaneous mycoses
51
mycoses: involve the skin, subcutaneous tissue, lymphatics and rarely disseminate systematically
subcutaneous
52
mycoses caused by dimorphic fungi that can produce serious systemic illness in healthy individuals
endemic
53
mycoses which can cause life-threatening systemic diseases in individuals who are immunosuppressed who carry implanted prosthetic devices, or vascular catheters
opportunistic mycoses
54
skin mycoses based on degree of tissue involvement
superficial
cutaneous
subcutaneous
systemic
55
t/f superficial mycoses is contagious via direct contact or indirect contact
t
56
etiologic agent of pityriasis versicolor
Malesezzia furfur
57
"an-an"
pityriasis versicolor or tinea versicolor
58
pityriasis versicolor: lesions are described as...
furfuraceous
59
Dx of pityriasis versicolor
KOH preparation or yellow flourescence on Wood's lamp
60
other causes of superficial mycoses
Piedraia hortae
Trichosporon
Phaeoannellomyces werneckii
61
spaghetti and meatballs
Malesezzia furfur under microscope
62
Dx of cutaneous mycoses
skin scraping
63
tx of cutaneous mycoses
antifungal creams
64
etiologic agents of cutaneous mycoses
dermatophytes
65
fungi that require keratin for growth
dermatophytes
66
dermatophytes
Trichophyton
Microsporum
Epidermophyton
67
"worm"; classified according to where the lesion manifests
Tinea
68
```
lesion is on the head
blister with scaly ring
ringworm of the scalp
spreads circularly forming bad spots
spread by contact with fomites, cats, dogs
```
tinea capitis
"galis"
69
fungal infection involving the groin area
tinea cruris
70
"hadhad"
tinea cruris
71
jock itch
tinea cruris
72
lesion of the foot
tidea pedis
73
athlete's foot
tidea pedis
74
alipunga
tidea pedis
75
live for weeks on shower floor or mat
tidea pedis
76
mycoses of the nails
tinea unguium
| onchomycosis
77
mycoses of hand
tinea manuum
78
mycoses limited to the beard areas of face and neck
tinea barbae
79
mycoses of the arms, legs, esp. on glabrous skin
"buni"
tinea corporis
80
kinds of subcutaneous mycoses
1. chromoblastomycosis
2. lymphocutaneous sporotrichosis
3. mycetoma
81
chronic mycosis of the skin and subcutaneous tissue
chromoblastomycosis
82
traumatic inoculation by dematiaceous fungi
chromoblastomycosis
83
etiologic factor of chromoblastomycosis
Phialophora verrucosa
fonsecaea compacta, F.pedrosoi, Cladophialophora carrionnii, rhhinocladiella aquaspersa
84
rose-picker's disease
lymphocutaneous sporotrichosis
85
etiologic factor lymphocutaneous sporotrichosis
sporothric schenkii
86
nodular and ulcerative lesion along lymph channels draining inoculation site
lymphocutaneous sporotrichosis
87
Madura foot
mycetoma
88
induces a granulomatous inflammation at the site of inoculation, usually the foot
may even cause osteomyelitis
mycetoma
89
mycetoma: nfection of subcutaneous tissute at site of inoculation can be caused by: ??
bacteria: actinomycotic
fungi: eumycotic
90
etiologic agents of mycetoma (fungi)
pseudoallescheria boydii
acremonium falciforme, madurella mycetomatis, madurella grisea, exophiala jeanselmei
91
t/f yeast form is invasive
T
92
usually caused by fungi in soil
systemic mycoses
93
systemic mycoses: inoculation
inhalation of spores
begins in lungs and spread to the rest of the body
94
kinds of systemic mycoses
1. histoplasmosis
2. blastomycosis
3. coccidiomycosis
4. paracoccidiomycosis
95
acquired by inhalation of dust particles from soil conntaminated with bird or bat droppings containing microconidia of Histoplasma capsulatum
histoplasmosis
96
etiologic factor of histoplasmosis
histoplasma capsulatum (intracellular parasite of macrophages)
97
defense against histoplasma
helper t-cells recognize fungal cell wall Ag --> produce IFNy --> induces macrophages to kill histoplasma within the macrophage
98
histoplasmosis: spectrum of manifestations
latent/self-limited pulmonary involvement (TB-like)
chronic progressive secondary lung disease
localized lesion in extrapulmonary sites
widely disseminated disease (fulminant disseminated histoplasmosis)
99
Dx of histoplasmosis
serologic procedures
100
etiologic factor of blastomycosis
blastomyces dermatitidis
101
round yeast cell dividing by BROAD-BASED budding
blastomyces dermatitidis
102
blastomycosis: spectrum of manifestations
pulmonary (suppurative granulomas)
disseminated
primary cutaneous (rare)
103
dx: blastomycosis
10% KOH or calcufuor white preparations of material from tissue
104
etiologic factor: coccidiomycosis
coccidioides immitis, c. posadasii
105
most virulent of all human mycotic agents
coccidiomycosis (coccidiodides immitis, c.posadasii)
106
etiologic factor: paracoccidiomycosis
paracoccidioides brasiliensis
107
paracoccidiomycosis: primary route of infection
respiratory (unapparent, asymptomatic)
subsequent dissemination can cause striking lymph node involvement
108
etiologic factors of candida
candida species
c. albicans
c. glabrata
109
most common cause of yeast infection
c. albicans
110
second most common disease causing species
c. glabrata
111
candida: stains
PAS (periodic acid Schiff)
| Gomori methenamine silver
112
microbial communities consists of mixture of yeast, filamentous forms and fungal-derive ECM
biofilm
113
factors that allow yeast to grow and cause infection
pH change
use of antibiotics
normal commensal flora breach
chemotherapy and bone marrow transplant
114
T/F candida is not capable of phenotypic switching
F
it is capable of phenotypic switching
115
reversible and random fashion
| change characteristics to adapt to changes in host environment
phenotypic switching
116
Host immune response
innate and T-cell responses
TH17 cells
neutrophils and macrophages
TH2: non protective (filamentous can escape phagocytosis
TH1: protective (yeast forms elicit this response)
117
degrades ECM proteins
aspartyl proteinases
118
resists oxidative killing
catalases
119
blocks neutrophil oxygen radical production and degranulation
adenosine
120
most common candida infection
thrush
121
superficial infection on mucosal surfaces of oral cavity
thrush
122
demonstrate white plaques and pseudomembranes resemling oral thrush on the esophageal mucosa
candida esophagitis
123
intense itching; thick curdlike discharge
candida vaginitis
124
infection of the nail proper
onychomycosis
125
infection of the nail folds
paronychia
126
infection of the hair follicle
folliculitis
127
infection of the most intertriginous skin (armpits, webs of fingers and toes)
intertrigo
128
infection of the penile skin
balanitis
129
infection of the perineum of infants
diaper rash
130
cutaneous candidiasis
```
onychomycosis
parachonia
folliculitis
intertrigo
balanitis
diaper rash
```
131
candida infection: blood-borne dissemination to other tissues or organs
invasive candidiasis
132
most common fungal endocarditis
candida endocarditis
133
etiologic factor of cryptococcus
Cryptococcus neoformans & C. gattii
134
cyptococcus: yeast or mold?
yeast form only (encapsulated yeast)
135
major risk factor of crpytococcus
high dose corticosteroids
136
soap-bubble lesions
cryptococcus (infects brain)
137
cryptococcus: tests
india ink
| cryptococcal antigen tests (recommended)
138
aspergillosis: yeast or mold?
ubiquitous mold
139
etiologic factor of aspergillosis
aspergillus sp.
A. fumigatus (most common)
140
forms fruiting bodes and septate filaments branching at acute angles
aspergillus
141
predisposing factors of aspergillosis
corticosteroids, neutropenia
142
portal of entry of aspergillosis
lungs (airborne conidia)
143
host response (aspergillosis)
macrophages phagocytose conidia
| neutrophils kill hyphae
144
Types of aspergillosis
1. colonizing aspergillosis
| 2. invasive aspergillosis
145
aspergilloma
growth of fungus in the pulmonary cavityies
minimal or no invasion of soft tissues
nose if often colonized
colonizing aspergillosis
146
fungus balls within cavities
colonizing aspergillosis
colonizes a healed lung scar from previous disease
147
aspergillosis associated with neutropenia
invasive aspergillosis
148
"target lesions"
| sharply delineated rounded gray foci and hemorrhagic borders
necrotizing pneumonia
149
aspergillosis: hematogenous dissemination
tendency to infiltrate BV
necrotizing pneumonia
invasive
150
zygomycosis (mucormycosis): yeast or mold
mold
151
phycomycosis
zygomycosis
152
caused by bread mold fungi
zygomycosis/mucormycosis
153
right angle branching
non septate
irregularly wide hyphae
zygomycosis
154
susceptible to zygomycosis
iron overload
corticosteroids
diabetes
neutropenia
155
pathogenesis: zygomycosis
thermotolerant spores (airborne, asexual)
inhalation, percutaneous exposure, ingestion
156
common in px with diabetes mellitus (zygomycosis)
rhinocerebelar zygomycosis
157
etiologic factor of pneumocystis pneumonia
pneumocystis jiroveci
158
AIDS-defining illness
pneumocystis pneumonia
159
definite demonstration of cysts or TROPHOZOITES
pneumocystis pneumonia
160
stain pneumocystis pneumonia
GMS stain
161
opportunistic mycoses
1. candida
2. cryptococcus
3. aspergillosis
4. zygomycosis
5. pneumocystis pneumonia
162
seen in mycotic keratitis
fusarium
163
one of the most drug-resistant fungi
| may affect cornea (contact lens)
fusarium
164
implicated in chronic fungal sinusitis
alternaria
