Endemic Mycoses Flashcards
in environment, histo, blasto, and cocci exist as
they convert to (morphology)
free living molds
histo, blasto convert to budding yeast
cocci converts to endosporulating spherules with endospores
regionality blastomycosis
midwest, detla south, non-coastal NE
regionality coccidiomycosis
desert south
regionality histplasmosis
MI river delta south+southern midwest
in host morphology, histoplasma capsulatum
oval budding yeast
narrow bund neck
inside phagoctytes+extracellular
histoplasma capsulatum convert to yeast form in
deep lung alveoli
if symptoms occur in histoplasma capsulatum, occur at ___ days
3-17 days post exposure
symptomology histoplasmosis
pulmonary - coin lesions and “buck shot” TB-like appearance on CXR
acute pericarditis
**disseminated **- spread via lymphatics, sites reach in mononuclear phagocytes
**ocular histoplasmosis syndrome - **blindness, ocular scaring due to fibrosing inflammatory response
**fibrosing mediastinitis - **enlargement of lymph nodes > leakage of caeous nodes into mediastinum
ocular histoplasmosis syndrome
blindness due to retinatl scaring resulting from fibrosing inflammatory resposne angainst yeast
fibrosing mediastinitis in histoplasmosis
excessive fibrotic response
lymph enlargement > leakage of antigen from caseous lymph nodes > inflammatory response > fibrosis
in histoplasmosis infection, mitocondria have receptors for _____ on the surface of ____ facilitating pahgocytosis
receptors for CD2/CD18 integrins on surface of macrophagees
treatment histoplasmosis infection
anti-fungal drug as adjunct
typically self-limited
for ___ in endemic areas, skin test reactivity does not indicate “active infection” because most have been exposed
histoplasmosis
histoplasma capsulata can be seen in ___ and ___ specimens
PAS and GMS stained specimens
outbreak locations, (qualitiy) blastomyces dematidis
stream, river areas vordered by rich moist soil
morphology blastomycecs dermatidis in host
large budding yeast (8-30 micrometers) with broad neck
infection of blastomyces dermatidis occurs via
incubation time
inhalation of microconidia, transmoring at body temperature to yeast
incubaion time is 4-6 weeks
symptomology blastomycosis
self-limited or chronic granulomatous suppurative mycosis
bronchogenic corcinoma
histoplasmosis
tuberculis
cataneous: painless, subcutaneous nodules or papules
blastomycosis vs TB
unlike TB, blasto lesions rarely caseate or calcify
in ___, phagocytosis may not occur due to size of the yeast cell
blastomycosis infection
coccidiodies immitis, posadasii, outbreak areas (quality)
soil rich in organic material
calcium sulfate and borates
hot arid or semi-arid climates
morphology in host coccidiodes
arthroconidia converting within 72 hours to spherules containing small endospores
morphology in environment coccidiodes
septate mulicellular hyphae
alternate cells developing into barrel shaped arthrocondidia
