Fungi Flashcards
Which are the medically important yeasts (and yeast like fungi)?
Candida spp
Cryptococcus spp
Pneumocystis spp
What are the medically important superficial fungi?
Dermatophytes (Tinea spp, malassezia furfur), aspergillus flavus, and yeast
What are the medically important deep or systemic mycoses?
Histoplasma capsulatum
Coccidiodes imitis
(Almost all have rare potential to become invasive/deep)
What are the medically important opportunistic fungi?
Candida spp
Cryptococcus spp
Aspergillus spp
Pneumocystis spp
What are the most common kinds of infections can Candida spp cause?
Systemic infections
Vulvovaginal candidiasis
Oropharyngeal colonization
Where is Cryptococcus spp usually found?
Associated with bird droppings (environmental yeast)
What are predisposing factors for an infection with Cryptococcus spp?
Occurs in immnocompromised hosts
-AIDS defining disease
The Vancouver Island Strain can infect immunocompetent hosts
What are predisposing factors for an infection with Pneumocystis jirovecii
Occurs in immunocompromised hosts
-AIDS defining disease
What would be the findings on a chest X-ray of a lung infection with Pneumocystis jirovecii?
Diffuse bilateral infiltrates.
What are the syndromes associated with Aspergillosis spp. infection?
Allergic syndromes- Allergic Bronchopulmonary Aspergillosis, Allergic sinusitis Colonization and Superficial syndromes Direct inoculation Invasive pulmonary Aspergillosis Tracheobronchitis Sinusitis Disseminated Infection
Which class of medically important fungi are referred to as “lid-lifters”?
Murmycosis
What group of medically important fungi are classified as contaminant level 3?
Dimorphic Fungi (Histoplasmosis, Blastomycosis, Coccidiodomycosis)
What can predispose neonates to Malassezia furfur infection?
Administering Total Parenteral Nutrition (TPN) -> high in lipids
What dimorphic fungi is most commonly contracted through hunting and trapping activities?
Blastomycosis
What dimorphic fungi is most commonly contracted through bat or chicken droppings?
Histoplasmosis
What dimorphic fungi is most commonly contracted in desert-like environments?
Coccidioidomycosis (Valley fever)
Yeast replicate by which method?
Budding
Molds replicate by which method?
Sexual or asexual spores. The fruiting body is called a conidia
The microscopic extensions of a growing mold are called?
Hyphae
What does an Aspergilloma look like on a chest x-ray?
A walled off granuloma with cavitation, similar to that of a TB granuloma.
How is a health host infected with Fusarium?
Direct traumatic inoculation.
What are the clinical infections Fusarium can cause?
Keratitis, onychomycosis, endophthalmitis, skin and MSK infections as well as disseminated infections in immunocompromised patients.
What is the clinical presentation of a Fusarium infection?
Fever and myalgias unresponsive to antibacterial antibiotics
Disseminated infections can include skin lesions in 60-80% of cases. These lesions start as papules but become necrotic.
Murcormycoses’ hyphae (once established in the lungs) has affinity for _____
Blood vessels
Murcormycosis infections can be found in what kind of patients?
Severely immunocompromised
Diabetes Mellitus
Trauma
Solid organ or hematopoetic transplants
What is the manifestation of acute disseminated histoplasmosis?
Rapid, debilitating, GI symptoms. bone marrow suppression, hepatospenomegaly.
What is the manifestation of chronic disseminated histoplasmosis disease?
Sub acute course taking about 10-12 months. Low-grade fever Weight loss weakness hepatospenomegaly mild hematological abnormalities focal disease
What is the manifestation of chronic pulmonary histoplasmosis disease?
Clinically and radiologically resembles TB
granulomatous
Periods of guiescence and sometimes spontaneous cure
What are the symptoms of a Blastomyces infection?
fever chills cough muscle aches joint pain chest pain
What is the manifestation of a primary Coccidiomycosis infection?
Flu-like symptoms and self limited in 60%
Can form a granuloma indistinguishable to TB
What is the incubation period of Coccidiomycosis?
10-16 days
Ringworm is what category of fungus?
Dermatophyte (Tinea spp)
What part of the body does tinea infect?
It colonizes the stratum corneum
How are Tinea spp infections classified?
By anatomical location. Tinea capitis (scalp, eyebrows, eyelashes) Tinea pedis (foot) Tinea unguium/onchomycosis (toenails) Tinea corporis (skin) Tinea barbae (beard) Tinea cruris (groin) Tinea manum (hands) Tinea versicolor (malassezia furfur)
What is the clinical manifesation of Tinea versicolor (malassezia furfur)?
Discolouration of skin (loss of pigment)
