Micro Test 3: Oppotunistic Mycoses
Card Set Information
Micro Test 3: Oppotunistic Mycoses
Name 4 Opportunistic Mycoses (occur in immunocompromised patients)
2 Main predisposing factors for opportunistic fungal infections
2) Impaired T-cell mediated immunity
What are the 4 organisms most frequently infecting patients with T-cell dysfunction?
Candida (mucocutaneous infections only)
5 disease forms of Candidiasis
Chronic mucocutaneous candidiasis
Which organism is a common cause of disease in the blood?
Candidaisis has a ____ mortality rate.
Oval yeast with a single bud
Candida albicans is seen as an _____
oval yeast with a single bud
As opposed to Cryptococcus neoformans, which is seen as an encapsulated oval, budding yeast (pigeon droppings)
Candida albicns form
pseydohyphase (germ tube)
Dormant spores of C. albicans
Which organism has pseudohyphae and chlamydiospores?
One of the most common manifestations of HIV infection.
Is this associated with disseminated candidiasis?
HIV candidiasis involves oropharynx, esophagus, or vagina.
3 things that have increased the incidence of Candidiasis.
Central venous access devices
Use of antimicrobial agents, corticosteroids, and central venous access devices have increased the incidence of ____
Candidal endocarditis occurs most commonly in (3 ppl)
IV drug users
Pts w/ prosthetic heart valves
Prolonged use of central venous catheters
IV drug users, patients with prosthetic heart valves, and IV drug users are at an increased risk of developing
How do you diagnose disseminated candidiasis?
CT scan, confirm with biopsy
Candidiasis Tx: What form?
Fluconazole prophylaxis; risk of resistance
AmpB- Systemic Candidiasis infections
Causative agent of Cryptococcis
Found in pigeon droppings
Cryptococcus neoformans is seen microscoppically as
Encapsulated oval, budding yeast
limits capsule formation!!!
What two things inhibit capsule formation of C. neoformans?
High salt, polysaccharides
Once in the lungs, they regenerate their capsules
Name two fungi that are NOT dimorphic.
C. neoforms causes:
Lung infection (often asymptomatic, but may produce pneumonia)
Predilection for CSF
Which organism has a predilection for CSF and can cause meningitis?
Name 3 diseases associated with HIV.
Candida albicans- thrush
Cryptococcus neoformans- meningitis (90%)
How do you treat Cryptococcus neoformans?
AmpB and flucytosine (2 wks)
Azoles (8 wks)
HIV (therapy for up to a year)
Which organism historically has infections in temperate areas? (ie. Australia) Infects
Animals and healthy individuals
Cryptococcus gatti historically causes infections in healthy individuals_____ areas.
Cryptococcus gattii (the Aussies) causes:
Causative agent of Aspergillosis
Which organism has septate hyphae and V-branching?
Aspergillus fumigatus grows only as a ____. Is it dimorphic?
mold, not dimorphic
2 differentiating factors of A. fumigatus
Infectious particle of A. fumigatus
Associated with infections of
Histoplasmoces can spread from ____ to _____
Aspergillosis can infect ____ and spread to ________
: lungs to skin
A. fumigatus: skin to body (lungs)
3 species of Zygomycosis
Rhizopus, Mucor, Absidia
4 Disease forms of Zygomycosis
Rhinocerebral (nasal passage--> brain)...Like animorphs!!!!
Which fungus has an overall mortality rate of > 50% with disseminated disease rates approaching 100%?
3 Risk factors for Zygomycosis.
Nonseptate hyphae, broad irregular walls, right angle branching
Aspergillos has a conidiaphore with conidiospores.
Zygomycosis has a _____ with spores
Facial pain w/ eye protrusion
Zygomycosis (very rapidly growing)