Fungi Flashcards
Yeast
unicellular, typically spherical fungi
hyphae
threadlike, branching, cylindrical tubules composed of fungal cells
molds
multicellular colonies composed of clumps
spores
reproducing bodies of mold
dimorphic fungi
can grow as yeast or mold depending on environmental conditions
saprophytes
live in and use organic matter as energy source
essential sterol in fungi
ergosterol
Pityriasis versicolor
superficial fungal infection that can lead to hyper or hypopigmented patches of the skin; caused by Malassezia furfur
Tinea nigra
superficial fungal infection that causes dark patches on soles of hands and feet; caused by Exophiala werneckii
Diagnosis of superficial fungal infections
skin scrapings mixed with KOH
Manifestation of keratin digestion
scaling skin, loss of hair, crumbling of nails
Tinea corporis
ring shape with red border in cutaneous layer
Tinea cruris
itchy red patches on groin and scrotum
Tinea pedis
cracking and peeling skin between toes
Tinea capitis
red scaly lesions with loss of hair
Tinea unguium
nails are thickened and discolored
Candida albicans
cutaneous fungal infection that can infect mouth, groin, vagina
Sporothrix schenckii
sporotrichosis (occupational hazard for gardeners), subcutaneous nodule that becomes necrotic and ulcerates, follows lymphatic vessels
Phialophora and Cladosporium
chromoblastomycosis, following a puncture wound a violet colored wartlike lesion develops
Histoplasma and blastomyces are endemic in what areas?
areas that drain into Mississippi river
Coccidioides is endemic to what areas?
southwest US and northern Mexico
Asymptomatic fungal infections
may involve a mild respiratory illness that goes unreported
Pneumonia caused fungal infections
mild pneumonia with fever, cough, chest S-ray infiltrates
Disseminated fungal infection
meningitis, bone lytic granulomas, skin granulomas and other organ lesions
Histoplasma capsulatum features
nonencapsulated, present in bird and bat droppings; inhaled causing infection of lung
Blastomyces dermatitidis features
found in soil and rotten wood, rare infection but may cause chronic disseminated disease
Coccidioides immitis
mild pneumonia in SW US, common in AIDS patients
Cryptococcus neoformans and Cryptococcus gattii
major manifestation is meningoencephalitis, mostly occurs in immunocompromised pts, may cause HA, nausea, confusion, staggering gait, CN deficits; can also cause pneumonia, skin ulcers and bone lesions
Candida albicans
typically seen in women with vaginitis, babies with diaper rash, AIDS pts, etc.
Diseases caused by Candida albicans in immunocompetent patients
oral thrush, vaginitis, diaper rash
Diseases caused by Candida albicans in immunocompromised patients
esophagitis, disseminated (found in blood)
Aspergillus major diseases
Allergic bronchopulmonary aspergillosis, aspergilloma, invasive aspergillosis
Manifestations of ABPA
asthma-type reaction, type 1 hypersensitivity
Aspergilloma
ball of fungus found in lung cavitations (malignancies or tuberculosis)
Mucormycosis
opportunistic disease typically seen in pts with acidosis, immunocompromised, burn patients, or pts on deferoxamine; rhinocerebral and pulmonary involvement
Actinomyces Israelii
bacteria acting like fungi, G+ rod; causes eroding abscesses; sulfur granules are often found in abscesses
Nocardia asteroides
G+ rod; acid-fast and very similar to TB, immunocompromised pts are most at risk
