Respiratory System Mycoses Flashcards
group that causes respiratory system mycoses
ascomycota
description of ascomycota
septate hyphae
multicellular filamentous hyphae at RT
release asexual spores with limited nutrients
spores inhaled–> switch to budding yeast in body
types of ascomycota
histoplasma
blastomyces
coccidiodes
mechanisms of immune system evasion
reduce number of PAMPs
hide PAMPs with extra layer
interfere with the antibodies/complement system
histoplasma morphology
2 forms
macroconidia- finger like projections (tuberculate)
microconidia- 2-4um ovals on hyphae branches
histoplasma in the body
switches to budding yeast
infects macrophages and affects ER and lysosomes
can spread within body
hisoplasma location
ohio river valley- KY, TN, OH
histoplasma comes from
soil and birds
lab acquired
histoplasma clinical symptoms
usually asymptomatic
can have fever, headache, substernal or pleuritic chest pain
resolution of histoplasma
calcified granulomas with yeast in lung
identification of histoplasma
ELISA for wall antigen
blastomyces morphology
single type of conidia
short hyphae- round/oval/pear shaped
blastomyces in the body
broad based budding yeast
thick walls
large
blastomyces spread
person to person or aerosolized
dirt close to water
lab acquired
blastomyces location
Mississippi and ohio river valleys
frequency of infections
histo > coccidio > blasto
blastomyces symptoms
asymptomatic pulmonary infection
noticeable disseminated- skin, bone, GI/UGT, CNS
fever, cough, pleuritic chest pain
blastomyces identification
sample from center of skin lesion- look for budding yeast
sputum sample
exoantigen test
coccidiodes description
thin hyphae
differentiate into arthroconidia (unicellular, barrel shaped)
coccidiodes in the body
swell to a large spherule filled with endospores
cannot be phagocytes
endospores can spread to surrounding tissues
coccidiodes spread
aerosolized
rare person to person
dirt disruption lab infections
coccidiodes location
southwest- SoCal, AR
coccidiodes is found in
alkaline soil
rodent or snake reservoir
coccidiodes symptoms
asymptomatic 60%
symptomatic- flu like
delayed hypersensitivity- erythema nodosum
coccidiodes resolution
self limited
nodule in lung with fungi in it
coccidiodes complication
progression to chronic pulmonary infection in immunocompromised
dissemination- cutaneous, bone, meningitis
coccidiodes identification
DNA probe
exoantigen testing
