Mycoses Flashcards
tinea versicolor
features / org
cutaneous causes hypopigmented areas of skin lesions with yeast and hyphae tends to recur live on keratinized structures
epidermophyton
trichophyton
microsporum
tinea versicolor
pathogenesis
(all cutaneous)
biproducts of fungi metabolism go into tissues and cause inflammation and vesicles around lesion
ring worm (dry scaly inside, red inflam blisters outside)
infection of hair shaft or nails -> thickening, discoloring
tinea versicolor
transmission
(all cutaneous)
direct contact (wrestling)
contact with pets
chronic in warm/moist areas of body
tinea versicolor
prevention / treatment
keep cool and dry
antifungal creams
permanent cure is difficult
sporotrichosis, “rose gardner disease”
features / org
sub-cutaneous
grows on soil and decaying vegetation
sporotrix schenckii
sporotrichosis, “rose gardner disease”
pathogenesis
granulomas (may be painless, last years, hard to eliminate)
HIV patients can disseminate
sporotrichosis, “rose gardner disease”
transmission
thorn-caused trauma (while gardening)
sporotrichosis, “rose gardner disease”
prevention / treatment
protect skin when gardening
antifungal drugs
coccidioides, “valley fever”
features / org
systemic
dimorphic (mold in soil, yeast in host)
coccidioides immitans
coccidioides, “valley fever”
pathogenesis
20% inhaled goes into organs
“desert bump” granuloma under skin
inhaled -> lungs -> “valley fever”
water dries, spores produced, inhaled, lungs, yeast cell replication and surrounded by chitin cell wall, hard to destroy by immune system, granulomas
coccidioides, “valley fever”
transmission
inhalation of spores close to water
in CA, AZ, NM, TX, northern mexico
increased when earthquake, at end of summer
firefighters at risk
increased in filipinos and african americans
coccidioides, “valley fever”
prevention / treatment
avoid travel to endemic areas
antifungals if immunocompromised
histoplasma
features / org
systemic
dimorphic (mold in soil, yeast in host)
intracellular (only one)
pneumonia possible
histoplasma capsulatum
histoplasma
pathogenesis
inhalation, lungs, macrophages in liver and spleen
cause granulomas in immunocompromised
HIV patients can disseminate
histoplasma
transmission
inhalation of soil spores
in river valleys (ohio, mississippi)
contaminated soil with bat guano
spelunkers at risk
histoplasma
prevention / treatment
avoid exposure
antifungals if immunocompromised
blastomycosis
features / org
systemic
dimorphic (mold in soil, yeast in host)
blastomyces dermatitides
blastomycosis
pathogenesis
granulomas in lung
HIV patients can disseminate
some in skin, genitals, upper resp tract
blastomycosis
transmission
inhalation of soil spores
in river valleys (ohio, mississippi)
males at risk
blastomycosis
prevention / treatment
no prevention
antifungals if immunocompromised
candidasis
features / org
opportunistic
dimorphic (mold and yeast in same host)
no disease in healthy people
non-environmental
candida albicans
candidasis
pathogenesis
overgrowth in mucosal membranes
mouth -> thrush
vagina -> yeast infection
HIV patients can disseminate
candidasis
transmission
part of normal flora, not transmitted
candidasis
prevention / treatment
antifungals if immunocompromised
cryptococcus meningitis
features / org
opportunistic
most common life-threatening fungal infection in AIDS
only yeast
cryptococcus
cryptococcus meningitis
pathogenesis
asymptomatic or pneumonia in healthy
HIV patients can disseminate to brain -> abscesses
50% no evidence of decreased health, normal CD4 count
cryptococcus meningitis
transmission
inhalation of org in soil
contaminated with pigeon droppings
cryptococcus meningitis
prevention / treatment
no prevention
antifungals for pneumonia / dissemination
aspergillus
features / org
opportunistic
fungal infection on eyes, skin, ears, lungs
only mold
aspergillus fumigatus
aspergillus
pathogenesis
fungus ball: overgrowth in cavities (sinus, lungs)
bronchial aspergilosis, like asthma, allergy
can cause anaphylaxis
aspergillus
transmission
inhalation of conidia in soil with decayed vegetation
black biofilm in showers
old a/c units
increased risk in chronic sinusitis and emphysema patients
aspergillus
prevention / treatment
no prevention
antifungals
antiinflammatory for lungs
