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Scopulariopsis spp.geicohands-like conidiophore

large, rough, annelloconidia (produced by annelides)

Aspergillus spp.

Conidiophores with phialoconidia

brush like

similar with Penicillium but has more volume & shorter conidia

Superficial Mycoses

1. Disease:

• Pityriasis versicolor (patches altered pigment, versicolor & scaling)
• Seborrhoeic dermatitis (includes Follicular pityriasis & Dandruff)

causative agent: Malassezia furfur

hyphae & yeast (spaghetti & meat balls)

Basidiomycete

Lipophilic yeast (loves fat/lipid)

can be systemic => nutritional, supplementation, associate with catheters  

1. Tinea nigra
• causative agent: Exophiala wernekii (dimorphic, Ascomycete, yeast in culture; mold in lession)
• form brown to black spots
• tropical disease
• palm & soles
• young F>M 
2. Piedra: infect hair, formation of waxy small, firm masses on hair
• Black
• black nodules on scalp
• causative agent: Piedraia hortae ()
• tropical, M>F (swimmers)
• White
• white nodules on beard, mustache, genital region
• causative agent: Trichosporon beigelii (mold, septate, hyphae)
• temperate & tropical, south US, M>F

Dermatophytes (skin infection)

• Trichophyton
• Microsporum
• Edidermophyton

All molds, septate hyphae
30-70% adults
incident increase with age

Techniques, Sapprophyte

Sexual stages of 3 classes:

Basidiomycetes

brown basidiospore

Zygomycetes

dark colored zygospore formed from fusion of 2 aseptate hyphae

Ascomycetes

the 2 celled ascospores are produced in a sac like ascus

Dermatophytes and other fungi that causes superficial infections:

limited to keratinized tissues. ie. skin, hair, nails

dermatophyte infection determined by observing skin scrapping in KOH wet mount

has macroconidia & microconidia

Microsporum canis

spindle-shaped, thick walled macroconidia.

has up to 15 septa.

Microsporum gypseum

thin wall
usually 4-6 septa

Epidermophyton floccosum

club-shaped macroconidia
2-3 septa
no microconidia

Tricophyton mentagrophytes
cigar-shaped
thin walled macroconidia
abundant
coiled hyphae
hair perforation positive

Tricophyton rubrum
cigar-shaped macroconidia
thin walled microconidia
Dermatophyte
anthropophillic (attracted to man*), zoophillic, geophillic [as pop. decrease, lose ability to mate]

Saprophytes: Organisms that live on dead organic matter

Aspergillus

chained conidia on phialides arise from swollen vesicle

Exogenous opportunistic fungus.

Scopulariopsis spp.

geicohands-like conidiophore

large, rough, annelloconidia (produced by annelides)

Penicillium

chains of conidia from branched conidiaphore

brush like, longer than Aspergillus

Penicillium marnefei

severe biohazard

intracellular (Histo too!!)

dimorphic

haploid, no sexual stage

most infected by HIV positive patients

Disease:(by inhalation)

once infected, cannot be cured

effect immune surpress individuals (ie. HIV)

Disribution:

Southeast Asia, nothern Thailand

Diagnose:

Culture, PCR, Serological test

Rhizopus

non-septate, wide hyphae

sporangia filled with sporangiospores

has rhizoids at base of sporangiophore

Rndogenous opportunistic fungi

Mucor

septate hyphae
sporangiospores in sporangia.

Alternaria

dematiaceous (dark colored)

club-shaped conidia