Mycology Flashcards
1
Q
Yeasts
A
Unicellular eukaryotic organisms, typically flat, confluent growth on media
2
Q
Molds
A
Growing hyphae. Dematiaceous or hyaline
3
Q
Dematiaceous
A
Dark, (brown-black) color on growth plates conidia/hyphae are brown-black
4
Q
Hyaline
A
Conidia/hyphae are lightly pigmented including shades of blue/green with lactophenol blue stain
5
Q
Hyphae
A
Microscopic fungal cell of a mold
6
Q
Aseptate
A
No breaks
7
Q
Septate
A
Has breaks
8
Q
Mycelium
A
Intertwined hyphae forming a thick mat
9
Q
Vegetative hyphae
A
Under surface of the agar
-Food absorbing
10
Q
Aerial hyphae
A
Above agar surface
-Supports sexual structures
11
Q
Blastic
A
Conidia formed by enlarged parent cell, septum forms to divide it to form a daughter cell
12
Q
Thallic
A
Division of a hyphal strand by formation of a septum into single cell units that then become conidia
13
Q
Telemorph
A
Sexual state
14
Q
Anamorph
A
Asexual state characterized by production of conidia or sporangiospores
15
Q
Phylum Zygomycota
A
The Bread Molds
Ex) Rhizopus - black bread mold
16
Q
Phylum Ascomycota
A
Sac Fungi
Ex) Yeast, morels, truffles
17
Q
Phylum Basidiomycota
A
Club Fungi
Ex) Mushrooms, puffballs, bracket fungi, rusts, smuts, toadstools
18
Q
Phylum Deuteromycota
A
Fungi Imperfi
19
Q
Mycoses
A
Fungal disease
20
Q
Superficial
A
Outermost layers of skin/hair, little pathology/cosmetic
21
Q
Cutaneous
A
Skin/hair keratin
22
Q
Subcutaneous
A
Skin, muscle, connective tissue immediately below the skin
23
Q
Systemic
A
Deep tissues/organs
24
Q
Mycotic diseases (4)
A
1) Hypersensitivity (Allergy)
2) Mycotoxicosis (Production of toxin)
3) Mycetismus (mushroom poisoning)
4) Infection
25
Farmer's Lung
Moldy hay
Aspergillus spp.
26
Malt worker's disease
Moldy barely
Aspergillus clavatus
27
Cheese washer's lung
Moldy cheese
Penicillium casei
28
Wood trimmer's disease
Moldy wood
Rhizopus spp., Mucor spp.
29
Opportunistic Fungi are found where?
-Soil, water, plants, i.e. ubiquitous
-Are saprobic
30
Ubiquitous
Found everywhere
31
Opportunistic Fungi - how do people get it?
-Contact through exposure. Some carry with no infection
-Conidia are inhaled
32
Opportunistic Fungi - who is affected?
-Rarely infect healthy people
-Injured/immunosuppressed/immunocompromised are at risk
33
Opportunistic Fungi - Growth
Grow rapidly
34
Saprobic
Live on decaying plant matter in soil, can become airborne
35
Opportunistic Fungi - Are they common?
-Very common in environment and are routinely found in sputum cultures and in labs (contamination)
36
Opportunistic Fungi - Pathogenic species
Apergillus & Zygomycetes
37
Opportunistic Fungi - Symptoms
Consistent with fungal disease. Varied depending on location within the human body
38
Aseptate (Zygomycota) Opportunists
-Terminal vesicle absent (have columellae at tips of sporangiophores)
-Terminal vesicle present
39
Septate Opportunists
-Dematiaceous opportunists
-Hyaline opportunists
40
Rhizoids
Root-like hyphae
41
Stolons
Interconnecting runners between rhizoids, vine-like
42
Columella
Supporting structure at the base of sporangia
43
Apophysis
Swollen, funnel shaped columella
44
Vesicle
A swollen hyphal end, specifically found in some zygomycetes and other fungi
45
Sporangium
Sac-like structures at tip of sporangiophore
46
Sporangiospores
Asexual spore of zygomycetes
47
Zygomycetes
Contains ALL aseptate fungi
48
Perfect fungi
Sexual and asexual
49
Zygomycetes lacking terminal vesicles
-Absidia spp.
-Apophysomyces spp.
-Mucor spp.
-Rhizopus spp.
50
Otomycosis
Ear infection
51
Zygomycetes with terminal vesicles
Cunninghamella spp. and Syncephalastrum spp.
52
Zygomycosis
-Infection via any zygomycota where the initial infection, often nasal sinuses, invades blood vessels and disseminates
-Can spread to brain and meninges causing meningoencephalitis
53
Zygomycosis - Treatment
Prompt treatment with amphotericin B often curative, proper diagnosis critical;
54
Glabrous
Way of describing culture plates - looks like lava rock
55
Dematiaceous Opportunists
Aureobasidium, Alternaria, Bipolaris, Curvalaria, Epicoccum, Nigrospora
56
Hyaline Opportunists
-Cause hyalohyphomycosis
-Acremonium, Apergillus, Chrysosporium, Fusarium, Gliocladium, Paecilomyces, Penicillium, Scopulariopsis, Sepedonium
57
Basics of disease
-Rarely is a single disease caused by a single microbe
-Rarely does a single microbe cause a single disease
-Exceptions: rabies virus, syphilis
58
Opportunistic Mycoses
Hyalohyphomycosis, Phaeohyphomycosis, Aspergillosis, Penicilliosis, Keratomycosis, Otomycosis, Sinusitis
59
Hyalohyphomycosis
Mycotic infection caused by a hyaline mold other than Aspergillis
60
Phaeohyphomycosis
Mycotic infection caused by dematiaceous molds not usually associated with infection
61
Aspergillosis
-Allergic bronchopulmonary aspergillosis
-Invasive aspergillosis
-Brain, heart, kidney
62
Aspergillosis - Allergic bronchopulmonary
Cough, wheezing, fever
63
Invasive aspergillosis
-Most common in immunocompromised
-Invade blood vessels and can infect any organ at this point
64
Aspergillosis - brain, heart, kidney
Fever, chest pain, SOB, Aspergilloma, if untreated usually deadly
65
Aspergilloma
'Fungas ball' in tissues of the lung itself
66
Penicilliosis - Cause
Caused by Penicillium, Scopulariopsis, or Paecilomyces spp.
67
Penicilliosis - Begins where?
Respiratory tract
68
Penicilliosis - Hematogenous dissemination
CNS, kidneys, endocardium
-Fevers, chills, weakness, enlarged lymph nodes and hepatosplenomegaly
69
Penicilliosis - Common where?
-China, Thailand
-Commonly infects HIV/AIDS patients
70
Keratomycosis - Infects what
Infection of the cornea of the eye, continuous with the conjunctiva
71
Keratomycosis - Predisposing factors
Include trauma or corticosteroid use
72
Otomycosis
-Fungal infection of the external auditory canal of the ear
-Caused by many different fungi
73
Otomycosis - Signs/symptoms
Inflammation, itching, reduced hearing (physical obstruction by hyphae)
74
Sinusitis
Inflammation of the nasal sinuses
75
Sinusitis - common in who?
Immunocompetent patients who suffer from allergic rhinitis
-If chronic infection is left untreated, could progress to CNS and become fatal
76
Superficial fungi
-Dermatomycoses
-Fungi that invade keratin containing layers of skin, hair and nails
-Often referred to as Tineas and Piedra
-Communicable skin diseases
77
Dermatophytes
-Dermatophytosis
-Fungi that infect keratin containing layers of skin, hair and nails specifically caused by one of the 3 genera: Microsporum, Epidermophyton, and Trichophyton spp.
-Communicable diseases
-Do not invade beyond keratin layers
-Tinea term used
78
Specimens for Superficial Fungi
-Skin scrapings
-Plucked hairs
79
Piedra
Affects the hair, no hair loss
-Cosmetic
-Discomfort
80
Superficial Tineas
Affect superficial skin, nails and hair
-Tinea nigra
-Tinea versicolor aka pityriasis versicolor
81
Anthrophilic
People loving - chronic
82
Zoophilic
Live on animals
83
Geophilic
Live in the soil
84
Microsporum - Infect what?
Infects skin and ectothrix hair
-Various species in Microsporum genus produce pteridine (fluorescent metabolite) fluoresces green-yellow under a Wood’s lamp.
85
Epidermophyton - infect what?
Infects skin and nails
86
Trichophyton mentagrophytes, rubrum and verrucosum - infect what?
Infect skin, nails and ectothrix hair
87
Trichophyton tonsurans, schoenleinii and violaceum
Infect skin, nails and endothrix hair
88
Dermatophyte Infections (Dermatophytosis)
-Exhibit centrifugal growth (ring like aka Tinea- latin for ringworm).
-Tinea is the first word in the names of the diseases The second word in the name identifies the body area affected. Ex) Tinea corporis – ringworm of the body
-Onychomycosis
89
Yeasts
-Some are normal flora (e.g. Candida albicans) - Endogenous infections
-Helpful – beer & bread (Saccharomyces cerevisiae).
-Opportunistic v. virulent pathogen (those not part of normal flora causing disease).
-Eukaryotic unicellular organisms that reproduce by budding
90
Clinically Important Yeasts
Candida, Cryptococcus, Rhodotorula, Geotrichum, Pneumocystis, Saccharomyces
Note: Candida albicans and Cryptococcus neoformans are the most common yeasts causing human disease.
91
Yeast - Laboratory ID
* Yeasts are obtained from any specimen source
* Proper ID relies heavy on biochemical ID lending nicely to commercially developed rapid kit tests.
* No special precautions or procedures are required such as in molds (Universal Precautions).
92
Germ tube test
* Take 0.5 mL of rabbit, fetal calf or human serum and place into a test tube.
* Take a small sample of the organism in question from the plate and place into the test tube.
- Do not take too much inoculum. Too much impedes germ tube production.
* Incubate at 37 degrees C for 3 hours.
* Take small drop, place on slide and coverslip and examine for germ tubes
93
Cleistothecia
Completely enclosed ascocarp, the membrane is intact. When cleistothecia rupture asci are released which contain 8 light brown oval ascospores.
