27 Cutaneous and Subcutaneous Mycoses Flashcards
Common fungal infections
Athletes foot
Ringworm of the scalp
Nail infection
.
What are Dermatophytoses?
Fungal skin infections
What are the genera that cause Dermatophytoses?
Epdermophyton
Trichophyton
Microsporum
What are the general properties of Dermatophytoses?
Filamentous fungi with septate hyphae that invade keratinized structures (skin, hair, nails)
Hyphae produce micro- and macro-conidia in lab
What are conidia?
wiki
are asexual, non-motile spores of a fungus and are named after the Greek word for dust, konia.
Which Dermatophytoses flouresces when exposed to UV light?
Microsporum
How do you name Dermatopytoses?
Tinea ____ body part.
What is Ectothrix?
What is Endothrix?
Fungal infection of hair from outside or inside.
What organism is Tinea Versicolor?
Malassezia furfur
What are the general properties of Tinea Versicolor aka Malassezia furfur?
Dimorphic with yeast and hyphae present in infected tissue.
What are the clinical features of Tinea Versicolor aka Malassezia furfur?
Hypopigmented areas appear on the skin
What organism is Tinea nigra?
Cladosporium werneckii
What are the general properties of Tinea Nigra aka Cladosporium werneckii?
Dimorphic with yeast and hyphae present in infected tissue.
What are the clinical features of Tinea Nigra aka Cladosporium werneckii?
Brownish spots on skin caused by melanin production by the fungus
What is the pathogenesis of Anthrophilic fungi?
Fragments of infected human skin or other superficial tissue come into contact with uninfected hosts. Hyphae invade and spread.
What is the source of Zoophilic fungi?
Animals, including pets
What is the source of Geophilic fungi?
Soil
What type of fungi (Anthro, Zoo, or Geo) is…
T. rubrum?
Microsporum canum?
Cladosporium werneckii?
T: Anthro
M: Zoo
C: Geo
What is the Dx of cutaneous fungi?
KOH mounts of clinical specimens are performed to detect fungal elements consistent with clinical picture.
Culture may be necessary for identification of specific macronidia by morphology
What is Tx of Cutaneous Mycoses?
Topical anti-fungal creams
What is Px for Cutaneous Mycoses?
Avoid exposure
Reduce skin moisture
I.D. the fungus by culture is helpful for I.D. the source fo infection and eliminating the source.
What are the natural environments of SUBcutaneous fungi?
Plants
Soil
(not animals)
How do SUBcutaneous fungi infect animal host?
Puncture or abrasion
What fungus causes Sporotrichosis?
Sporothrix shenkii
What are the general properties of Sporothrix shenkii aka Sporotrichosis?
Classical dimorphism growing as yeast in host tissue and hyphae in the environment.
What shape are Sporothrix shenkii aka Sporotrichosis as yeast in tissues?
Cigar shaped.
What are the pathogenesis and clinical features of Sporothrix shenkii aka Sporotrichosis?
Introduced by puncture
Nodular lesions emanate from site of inoculation.
What occurs in immunosuppressed patients that have been infected with Spororthrix shenkii aka Sporotrichosis?
Disseminated infection
What fungus cause Chromoblastomycosis?
Several soil fungus termed dematicaceous fungi (fungus with brown to black melanin
How does the fungus that causes Chromoblastomycosis infect the host?
Introduced by puncture
What are the clinical features of Chromoblastomycosis?
Slow growing wart-like lesions containing brown fungal cells
What is Dx of SUBcutaneous mycoses?
KOH mounts may be useful if lesions appear on surface of skin
Biopsies followed by histology and culture may be required to demonstrate fungi in infected tissue
What is the Tx for SUBcutaneous mycoses?
Oral AZOLE therapy
Surgery may be required
What is Px for SUBcutaneous mycoses?
Wear protective clothing when coming into contact with abrasive plant structures
