Mycology Flashcards
Treatment for Pneumocystis jiroveci pneumonia (PJP)?
- causes life-threatening fungal pneumonia in HIV pts
- NO response to anti-fungal treatment
- antibiotics recommended
Candidiasis is an ____ infection.
opportunistic
Diagnosis of Candida albicans?
- direct microscopy — germ tube formation and chlamydospores exclusive to C. albicans
- obtain culture
What is a unique characteristic for Candida albicans?
germ tubes (in presence of serum)
What are the multiple forms of Candidiasis?
pseudohyphae, true hyphae, germ tubes
cutaneous, oral, thrush, and vulvovaginal are some examples
What is the 4th leading cause of nosocomial bloodstream infections?
Candida species
Virulence Factors of Cryptococcus neoformans?
- polysaccharide capsule (anti-phagocytic,
immunosuppressive) - melanin synthesis — (evades immune system)
- most infections are asymptomatic
- may present as isolated pulmonary nodule (carcinoma)
- (this fungi is very difficult to get rid of which is why may cause death in a patient!)
Opportunistic infections are NOT:
thermally dimorphic
What is the cause of desert rheumatism?
coccidioidomycosis
Desert rheumatism can cause (2):
- severe joint pain
- meningitis
What does Malassezia furfur cause?
- causes superficial mycoses
* location — trunk, neck, face, arms • disease — tinea versicolor
What is the pathogenesis of Tinea versicolor?
- chronic or relapsing mycosis
- round or oval hypo- or hyper-pigmented macules covered with thin scales
Rounded, thick walled, and quite resistant; very classic of candida albicans
Chlamydospores
TRUE OR FALSE:
C. albicans can form multiple buds that do not detach during asexual reproduction.
True
C. albicans produces sausage like chains called:
pseudohyphae (which are are used for identification)
C. albicans can form different kinds of spores depending on the conditions, which allows them to:
thrive in different conditions and become pathogenic
C. albicans = ___
pleomorphic
What are the different spores that C. albicans can form?
- Ovoid cells
- Pseudohyphae
- Germ tube
- Filamentous
Form different structures at different temperatures = ?
thermal dimorphism
What are some examples of fungi that are thermally dimorphic?
- Blastomycesdermatitidis
- Coccidiodes immitis
- Histoplasma capsulatum
- Paracoccidiodes brasiliensis
How do you diagnose zygomycosis (mucormycosis)?
- microscopy of tissue for presence of NON-SEPTATE
hyphae branching at wide angle (90 degrees) and spores in sac - no serological tests
- culture of non-sterile sites, like lungs or sinuses
Tinea pedis = ? Tinea capitis = ? \_\_\_ = jock itch \_\_\_ = onychomycosis Tinea corporis = ?
Pedis = athlete's foot Capitis = Scalp hair infection Cruris = jock itch Unguium = Onychomycosis Corporis = ringworm
Type of pathogen that can invade and grow in a healthy, non-compromised host.
True pathogen
Primary portal of entry for true pathogenic infections?
Respiratory
Primary portal of entry for opportunistic infections?
Respiratory and Mucocutaneous
Degree of virulence for opportunistic infections?
Limited (only immunocompromised ppl get it)
Degree of virulence for true pathogenic infections?
Well-developed (anybody can get it)
Dermatophytoses is also called:
cutaneous mycosis
Sporothrix schneckii causes what disease?
Sporotrichosis
Discuss Sporotrichosis.
- Thermally dimorphic
- Obtained from puncture wounds during gardening and outdoor activities
- Travels through lymph nodes; “Rose-picker” disease
Microscopy of Sporotrichosis shows:
cigar-shaped budding yeast in pus or tissues
