- hair, skin, nail infections - break down and utilize keratin Trichophyton, Microsporum, Epidermophyton (remember two -phyton and one sporum)

- Tinea corporis: body - Tinea cruris: groin - Tinea pedis/manuum: food/hand “Athletes foot” - Tinea unguium: nails - discoloration

Mycology Flashcards by Stephanie L

What is the eukaryotic cell wall made of?

Chitin

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What phyla has ribbon like non-septate hyphae?

Zygomycota

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Deuteromycota (fungi imperfecti)

Asexual reproduction by Conidia

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4 phyla

Zygomycetes
Ascomycetes
Basidiomycetes
Fungi Imperfecti (Deuteromycetes)

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What agar should be used for hair, skin, and nail scrapings?

Mycosel agar - contains antibacterial and antifungal, KOH helps break down tissue for dermatophytes

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Media for dimorphic fungi and dermatophytes?

Sabouraud dextrose agar (SDA)

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Media that inhibits bacteria (for initial isolation except dermatophytes)

Inhibitory mold agar (IMA)

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2 types of blood culture media

Inhibitory mold agar - inhibits bacteria and isolates fungi

Brain-heart infusion agar

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BHI + gentamicin + chloramphenicol + sheep’s blood

C. neoformans from contaminated specimens

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What is Niger (bird) seed agar for?

Isolation of C. neoformans - brown colonies due to melanin production

Also for C. Albicans (yeast cells only) and C. Dubliniensis (extensive pseudo-hyphal growth)

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What is cornmeal agar (CMA) for?

Wide range of fungi but mainly fungi imperfecti

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What is malt extract agar for? (MEA)

Zygomycetes

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What is yeast extract phosphate medium for? (YEP)

Blastomyces dermatitidis and histoplasma capsulatum

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What is dermatophyte test medium (DTM) for?

Dermatophyte recovery from contaminated specimens, media turns pink —> red for dermatophytes

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Rhizopus vs. Mucor?
(Part of Mucorales)

Rhizopus: brown rhizoids at base of sporangiophore, umbrella structure at end of conidiophore (most common Mucorale), sporangia/sponrangiospores not retained

Mucor: no rhizoids, sporangia/sporangiospore stays intact

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Dermatophytes

hair, skin, nail infections
break down and utilize keratin

Trichophyton, Microsporum, Epidermophyton
(remember two -phyton and one sporum)

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Cutaneous mycoses (disease) in ringworm/Taenia

Tinea capitis: scalp hair loss
- Ectothrix: outside the shaft, permanent hair loss
- Endothrix: inside the shaft, temporary hair loss
- Favus: thick yellow crust, caused by T. schoenleinii
- Tinea barbae: beard hair loss, from animals

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Ringworm infections

Tinea corporis: body
Tinea cruris: groin
Tinea pedis/manuum: food/hand “Athletes foot”
Tinea unguium: nails - discoloration

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Trichophyton (Ascomcetes Phylum)
Part of Dermatophytes

Infected hairs do not fluoresce under Wood’s Lamp (UV)

Macroconidia - club shaped, rare, thin walled, smooth

Microconidia - numerous, spherical, pyriform (teardrop) or clavate (clublike)

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Trichophyton rubrum

Does not perforate hair (ectothrix)

Slow growing

Urease (-)

Cherry red reverse surface

Microconidia - slender, clavate (clublike), tear shaped, birds on wire

Macroconidia: cigar shaped, rare

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Trichophyton mentagrophytes

Perforates hair (extothrix)

Rapid growing

Urease (+)

Orange-red reverse surface

Coiled spiral hyphae

Microconidia - grape-like clusters

Macroconidia - cigar shaped

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Trichophyton tonsurans

Epidemic form of tinea capitis (US)

Slow grower

Endothrix

Buff to brown, wrinkled, suede like

Reverse - yellow/reddish brown

Microconidia - flat base “matchstick”

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Microsporum audouinii
(Dermatophytes)

Antler and raquet hyphae

Tinea capitis in children

Anthropophilic (attracted to humans as a source)

Ectothrix

Hair shafts fluoresce yellow-green

Cotton-y, salmon pink to reddish brown culture

Rice grain slopes (orange color on rice, not fluffy like M. canis)

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Microsporum canis
(Dermatophytes)

Most common cause of ringworm in dogs and cats

Hair shafts fluoresce yellow-green under UV

Colonies: white, feathery border with yellow fringe
Reverse - bright yellow (or orange when aged)

Macroconidia: thick walled, spindle-shaped with curved ends, spiny projections on surface

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Microsporum ferrugineum (Dermatophytes)

*Endemic juvenile Tinea capitis in humans Bamboo hyphae*

Epidermophyton floccusum (Dermatophytes)

Skin and nail infection (*not hair*) Anthropophilis Colonies: brown yellow to olive gray or khaki, lumpy Reverse - orange-brown, thin yellow border *No microconidia* Macroconidia: club shaped, rounded ends

Aspergillus fumigatus

- White to blue-green colonies - Dichotomous branching of hyphae - Conidial heads

Aspergillus niger

Peppery colonies Dark pigmented spores

Penicillium

Blue-green colonies, velvety *Brushlike or broomlike conidiophores*

Paecilomyces/Purpureocillium lilacinum

Pink fuzzy Looks similar to penicillium but pointier and oblong spores

Fusarium

Canoe shaped macroconidia Pink on media Contact lens wearers 100% mortality in BM transplant infections

Blastomyces dermatitidis

Broad base, lollipop like Sexual stage - Ajellomyces dermatitidis Lungs —> disseminates

Coccidoides immitis

Valley Fever Inhalation of arthrospores from soil or dust Ice rink colonies *Barrel-shaped arthroconidia Spherules*

Histoplasma capsulatum

Cave disease/Darling disease *Birds and bats Tuberculate macroconidia*

Sepedonium

Looks like histoplasma but noninfectious

Sporothrix schenckii

*Rose Gardener’s Disease* Transmission: thorns *Flowerets attached to conidiophore Cigar bodies*

Paracoccidioides brasiliensis

South American blastocycosis Chronic granulomatous disease *Mariner’s Wheel or Ship’s Wheel*

Talaromyces (Penicillium) marneffei

Wine red pigment Looks like penicillium

Hortaea werneckii

Tinea nigra - skin infection affecting palms of hands and soles on feet (black non-scaly macules) Hyphal fragment and budding yeast

Piedraia hortae (black piedra)

Hair and scalp infection Dark brown black nodules on hair Nodules contain asci

White grain Mycetomas

Pseudallescheria boydii Acremonium Fusarium

Pseudallescheria boydii

Sexual stage Asexual stage = Scedosporium boydii

Acremonium

Looks like a beehive (on an acre)

Black grain Mycetomas

Curvularia Madurella mycetomatis Exophiala jeanselmei

Curvularia

Looks like croissants (curved conidia)

Madurella

Causes most cases of black grain eumycotic mycetoma in Africa

Chromoblastomycosis

Copper bodies Cladophialophora Phialophora verrucosa Fonsecaea pedrosoi Rhinocladiella aquaspera

Cladophialophora

Attaches at 2 spots

Phialophora verrucosa

Vase shaped phialides with cup-like collarettes

Fonsecaea

Copper pennies *Looks like asterisks*

Rhinocladiella aquaspera

Not branched, looks like longer stem than Cladosporium

Phaeohyphomycosis

*Infection caused by dematiceous fungi)

Alternia

Drugstick-like conidia

Bipolaris

*Zig zag Peas in a pod*

Exseronilum rostratum

Fungal meningitis, looks similar to Bipolaris kind of

Pneumocystis jirovecii

Pneumocystis pneumonia (PCP) HIV/AIDS Cyst, trophozoite, sporozoites stages Needs tissue culture to grow (can’t grow on regular fungal media)

Yeast that buds asexually

Blastoconidia

Candida albicans

True germ tube Green on chromagar Pseudohyphae

C. glabrata

Mauve colonies on CHROM Rapid assimilation of Trechalose Does not form pseudohyphae (feet) on colonies funginemia in immunocompromised patients, fluconazole resistant

C. krusei

Urea (v) Innate resistance to Fluconazole Resistance to Amphotericin B

C. dubliniensis

Cannot grow at 42-45°C (differentiates from C. albicans)

C. auris

Serious global threat Resistant to all 3 antifungals Does not form pseudohyphae or germ tube Can persist on surfaces and spread between patients

Cryptococcus neoformans

Polysaccharide capsule Stain: India ink C. neoformans and C. gattii produce phenoloxidase —> produces brown pigment on Niger Seed Agar

C. gattii vs. C. neoformans

C. gattii turns blue on CGB agar C. gattii from Eucalyptus trees

Trichosporon

White piedra Numerous anthroconidia - rectangular anthroconidia with round ends Urease (+)

Malassezia furfur

Tinea versicolor - brown lesions on light skin people, light lesions on darker skin people

Malassezia pachydermatis

Fungemia in immunocompromised patients

Malessezia

*Spaghetti and meatballs hyphal arrangement Bowling pin or pop bottle morphology Budding yeast with collarettes*

Rhodotorula

Bright salmon pink color Urease (+) Capsulated

5-Fluorocytosine (Flucytosine)

DNA and Protein Synthesis Inhibitor

Fluconazole (part of Azole Agents) and Amphotericin B

Cell Membrane Inhibitor C. krusei - resistant to fluconazole and Amphotericin B Amphotericin B - binds esterol

Echinocandin (1, 3 beta-glucan synthase)

Glucan synthesis inhibitor

Sterile structures on which spore bearing Phialides are born in Penicillium

Metulae

Sexual phase of zygomycetes

Zygospores