31: Fungal infections of the respiratory tract Flashcards
organisms and disease in sinuses
zygomycetes cause mucormycosis
organism and disease in oral cavity
candida causes thrush and eposhpagitis
histoplasma cuases
histoplasmosis
blastomyces cause
blastomycosis
paracoccidiodies cause
paracoccidioidomycosis
coccidiodies cause
coccididioidomycosis
cryptococcus causes
cryptococcosis
pneumoctstis causes
PCP
-in immunosuppressed
aspergilus causes
aspergillosis
- in immunosuppressed
what are the three zygomycetes
rhizopus
absidia
mucor
describe the zygomycetes group
non-septate hyphae
sporangia bearing sporangiospores
rhinocerebral zygomycosis
- most common form of zygomycosis
- primarily in diabetic patients
- starts in sinuses and moves
nasal congestion, blood tinged rhinorrhea, tender sinuses, headache and fever
-edema and visual disturbance
rhinocerebral zygomycosis
zygomatic infection of the skin
traumatic inoculation
zygomatic infection of the GI
neonates and premature infants
broad aseptate hyphae observed in blood vessels branching at right angles
zygomycoses (mucormycosis)
treatment for mucormycosis caused by zygomycoses
amphotericin B
candida form as normal flora
yeast
candida form within tissues
hyphal form
- diffuse erythema and white patches on the surface of the buccal mucosa, throat, tongue and gums
- plaques scraped away revealing raw lesion
oral cadidiasis (thrush)
what are some cuases of oral candidiasis in adults
steroids
antineoplastic drugs
antibiotics
what are the white lesions of thrush composed of?
yeast and pseudohyphal forms of c. albicans
treatment for thrush
mouth washes or lozenges of nystatin and azole compounds
4 dimorphic systemic mycoses
- histoplasma capsulatum
- blastomyces dermatitidis
- paracoccidioides brasiliensis
- coccidioides immitis
dimorphic fungi
molds in environment, yeast in tissues during infection
non-dimorphic systemic mycoses
cryptoccus neoformans
- encapsulated yeast in environment and man
where is histoplasmosis most prevalent
missippi and ohio river valleys
darling’s disease, cave dwellers disease or spelunkers disease
hisoplasmosis
histoplasmosis is cuased by
histoplasma capsulatum
clinical syndrome of histoplasmosis
inhaled spores are phagocytosed by pulmonary macrophages and converted to yeast form, replicate and spread
- mild flu like illness with dry cough, fever and fatigue
- calcification of pulmonary lesions
pulmonary histoplasmosis
- fever, night sweats, anorexia, weight loss, and fatigue in addition to repiratory sympotoms
- hepato and splenomegaly and lymphadenopathy
chronic pulmonary and disseminated histoplasmosis
histoplasmosis treatment
amphotericin B
- AIDS and immunosuppressed require lifelong suppressive therapy with azoles
endemic in ohio and missippi river valley and missouri and arkansas river basins
blastomycosis
gilchrist’s disease, chicago’s disease
blastomycosis
causative agent of blastomycosis
blastomyces dermatitidis
how do you distinuish the yeast of b. dermatidis from the yeast of h. capulatum
dermatidis: larger size and very thick cell walls
disseminated blatomycosis
skin lesion and bone necrosis, prostate infections
treatment for blastomycosis
amphotericin B
-azole for umcomplicated pulmonary disease
limited to tropical regions of south and central america
paracoccidiomycosis
90% of clinical disease occurs in men
paracoccidioidomycosis
causative agent of pparacoccidioidomycosis
paracoccidioides brasiliensis
“ships wheel”
“mickey mouse ears”
paracoccidioidomycosis
san joaquin valley of cali and in southern arizon
coccidioidomycosis
following inhalation the fungus converts into a spherule
coccidiodidomycosis
- multinucleated structure produces hundreds of spores
“desert rheumatism”
- fever, nodules, arthralgia
disseminated disease of coccidioidomycosis
develops slowly with increasing headache, fever, stiff neck, and other neurological signs
-fatal if untreated
coccidial or cryptococcosis meningitis
coccidiodiomycosis treatment
azole and amphotericin B for meningitis and disseminated disease
leading form of fungal meningitis
cryptococcal meningitis
commonly found in soil with bird droppings
- cryptococus neoformas
- histoplasma capsulatum
cryptococcosis diagnosis
india ink stain!
treatment of cryptococosis meningitis
6-10 wks amphotericin b and 5-fluorcytosine or fluconazole
pneumocystis jiroveci carinii pneumonia PCP
highly lethal form of pneumoia occuring primarily in the immuno-compromised
etiology of PCP
pneumocystis carinii/jiroveci
describe pneumocystis carinii/jiroveci
- single celled eukaryotic organism similar to fungi
dyspnea, nonproductive cough, and fever
- interstitial pneumoonitis with cellular infiltrate
- weakness, tachypnea and cyanosis
PCP
PCP organisms
trophozoite
sporozoites
cysts
PCP treatment
trimethoprim-sulfamethoxazole
interferes with folate synthesis pathway of organism
most common types of aspergillosis associated with disease
a. fumigatus and a. flavus
mold in both environment and man
“fungus balls”
colonization of pre-exiting lung lesions by aspergillomas
-typically unilateral
space occupying lesions that move as the patient changes position, hemoptysis
aspergillomnas
septate hyphae with v-shaped branches at a 45 degree angle
aspergillosis
aspergillosis treatment
- azole
- echinocandin
- amphotericin B
- surgical removal of aspergillomas