Fungal Pathogens Flashcards
cell-mediated immunity and fungal infections
- innate - neutrophils
- adaptive - CD4+ TH1 cells
which of the microbes are the opportunists
- yeast and molds
which are the yeast
- candida
- cryptococcus
- pneumocystis
which are the molds
- aspergillus
- mucor and rhizopus
which are dimorphics
- histoplasma
- blastomyces
- coccidiodes
which are branching bacteria
- actinomyces
- nocardia
what does dimorphic mean
- one phenotype in the environment and another phenotype in the infected host
what are conidia
- spores
candida species are what shape in tissue
- budding yeasts
- pseudohyphae
candida species - _____ formation at 37 degrees C is diagnostic
requires
- germ tube formation
- culture (Sabouraud agar)
candida species - ______ infections are common
which type?
- extra pulmonary
- chronic mucocutaneous candidiasis
- blood stream (candidemia)
candida species - candida pneumonia is _____ except in
- rare except in neutropenic patients
candida species - treatment for pneumonia requires
- isolation from tissue biopsy
candida species treatment
- echinocandins
- amphotericin B for invasive infections
CANDIDA => CABE
cryptococcus neoformans structure
- heavily encapsulated yeast
cryptococcus neoformans - most common manifestation
- meningitis
cryptococcus neoformans - pulmonary symptoms
- nonspecific (cough, fever, malaise)
cryptococcus neoformans - evaluate for ____ or ____ when either one is found
- pneumonia
- meningitis
cryptococcus neoformans - diagnosis by
- direct visualization (India ink)
- culture
- antigen detection
cryptococcus neoformans treatment
- amphotericin B
- flucytosine
Crypt AF
pneumocystis jirovecii structure
- disc-shaped (cyst like) yeast
pneumocystis jirovecii - extrapulmonary infection _____ except in
- rare except in late AIDS
pneumocystis jirovecii - worse outcomes in
- HIV - immunocompromised than HIV+
pneumocystis jirovecii - on CXR
- diffuse interstitial pneumonia with ground glass infiltrates
pneumocystis jirovecii - diagnosis by
most common stain
- direct visualization in lung tissue or bronchoalveolar lavage induced sputum
- silver stain most common
pneumocystis jirovecii treatment
- sulfamethoxazole and trimethoprim
a. k.a. bactrim
throw it BAC at club PJP
aspergillus fumigatus structure
- septate hyphae with V shaped brainching
aspergillus fumigatus associated with ____ malignancies
- hematologic
aspergillus fumigatus associated with these conditions
- catheter associated infections
- allergic bronchopulmonary aspergillosis
- brain abscesses
- sinusitis
Aspergillus = CABS
get yout Ass in the cab(s)
allergic bronchopulmonary aspergillosis is what type of hypersensitivity
- IgE mediated type I
aspergillus fumigatus grows in what structure
can cause
- cavities in lungs
- can cause hemoptysis
aspergillus fumigatus - diagnosis by
- direct observation in tissue
aspergillus fumigatus treatment
- voriconazole
AFV (America’s Funniest Videos about Aspergillius Fucking People Up)
mucor and rhizopus also known as
- zygomycetes
mucor and rhizopus structure
- aseptate hyphae with wide angle branching
mucor and rhizopus - hallmark
- necrosis following invasion of blood cells (angioinvasion)
mucor and rhizopus - symptoms of pulmonary infection
- prolonged fever
- airway obstruction
- hemoptysis
mucor and rhizopus - diagnosis by
- direct observation in tissue
mucor and rhizopus treatment
- amphotericin B
MR AB
histoplasma capsulatum structure
- oval yeast cells inside tissue macrophages
what organisms of a fungal homolog of MTB
- histoplasma capsulatum
histoplasma capsulatum - high exposure can cause
- pneumonia with cavitary lesions
histoplasma capsulatum - diagnosis by
- direct observation in tissue
- culture
- urine antigen test
UCT –> urine, culture or tissue observation
histoplasma capsulatum - treatment for asymptomatic or mild infection
- none
histoplasma capsulatum - treatment for serious disease
- itraconazole
- amphotericin B
HISTO => IAB
histoplasma capsulatum is an intracellular pathogen of
- macrophages
blastomyces dermatitidis structure
- thick walled yeast with broad based budding in extracellular spaces
blastomyces dermatitidis - acute pneumonia looks like
importance of this
may progress to
- bacterial
- does not respond to antibacterial therapy
- ARDS
blastomyces dermatitidis - chronic pneumonia looks like
- TB and histo
blastomyces dermatitidis - diagnosis by
- direct observation in tissue
- culture
blastomyces dermatitidis - treatment
what status of it do we treat?
- intraconazole
- amphotericin B
- treat even asymptomatic infections
blasto = b = cover your bases = always treat
coccidiodes immitis also known as
- valley fever
coccidiodes immitis structure
- spherules (with endospores inside) in tissue and barrels in environment
coccidiodes immitis causes (symptoms)
- erythema nodosum (desert bumps)
- lung nodules or lung cavities
coccidiodes immitis diagnosis by
- direct observation in biopsy
- culture (BAL or tissue)
- skin test
coccidiodes immitis - treatment
- fluconzole
- amphotericin B
COX are FAB
actinomycetes israelii structure
- filamentous
- gram +
- anaerobe
- normal oral flora
actinomycetes israelii - causes what conditions
- oral/fascial abscesses (sulur granules)
- PID with IUDs
actinomycetes israelii - rarely ______
- bronchopulmonary
actinomycetes israelii resembles
- neoplasia or TB on CXR
actinomycetes israelii diagnosis by
- direct observation in tissue biopsy
actinomycetes israelii treatment
- penicillin
Nocardia asteroides structure
- beaded filaments
- gram +
- weakly acid fast
- aerobe
Nocardia asteroides _____ in immunocompromised patients
- brain abscess
Nocardia asteroides - pulmonary disease typical with
- pneumonia or lung abscess with cavity formation
Nocardia asteroides diagnosis by
- direct observation
- culture
Nocardia asteroides treatment
- sulfamethoxazole/trimethoprim
