Lecture 20-22- Mycology Flashcards
Define heterotroph
obtain carbon by consuming organisms
What is contained in fungal cell membranes?
Sterols (ergosterol)
Unicellular fungal form-
yeast
Multicellular fungal form-
mold
Fungi that switch between yeast and mold forms-
dimorphic
Branches of multicellular mold-
hyphae
Group of tangled hyphae-
mycelium
Cross walls within hyphae-
The two categories based on them
Septa
Septate vs coenocytic
Dark pigmented hyphae-
Dematiaceous fungus
Non-pigmented hyphae-
Hyaline fungus
What test can be used to detect Fungal pathogens in the blood (low specificity?
Beta D-glucan assay
What type of stain looks at fungal hyphae in large sections of tissue
Calcofluor stain
What is the difference between Sabouraud Dextrose Agar and Sabouraud Dextrose Agar with cycloheximide
Both inhibit bacteria, cycloheximide inhibits fast growing saprophytic fungus
What cell wall molecule is often targeted by antifungal drugs
Ergosterol
What is Griseofulvin effective against?
dermatophyte cell division
What are dermatophytes?
Fungal species that infect skin
What species is the major reservoir for Microsporum canis?
Cats
What are the three most common dermatophyte species?
Microsporum canis
Trichophyton mentagrophytes
Trichophyton verrucosum
What organism causes ringworm infections in cattle?
Trichophyton verrucosum
What organism causes pseudomycetomas in Persian cats?
Microsporum canis
What causes avian ringworm or Favus?
Microsporum gallinae
How to dx Microsporum canis in cats
Woods lamp fluorescence
Can a DTM tube be used for presumptive identification?
Yes
How should Griseofulvin be administered to fight dermatophytic infections?
Orally
Which yeast has a footprint shape?
Malassezia pachydermatis
Which nonbudding yeast causes thrush?
Candida albicans
What fungus is transmitted through pigeon droppings?
Cryptococcus neoformans
What fungal pathogen is emerging and found in eucalyptus trees
Crytptococcus gattii
What fungal pathogen attackes the CNS in immunocompromised patients and can cause granulomatous lesions?
Cryptococcus
What fungal pathogen has a visible capsule
Cryptococcus
Which fungal pathogenes are thermaly dimorphic
Histoplasma
Blastomyces
Coccidiodes
Sporothrix
What fungal pathogen is the most common systemic mycosis?
Blastomyces dermatidis
What fungal pathogen is characterized by a thick cell wall and broad-base budding
Blastmyces dermatidis
Where is blastomyces dermatidis endemic
Ohio-Mississippi river valley
What fungal pathogen is characterized by living within macrophages and inhabiting bird droppings in the Ohio river valley?
Histoplasma capsulatum
What manifestation of histoplasma capsulatum can occur frequently in dogs, but not people
Severe diarrhea and wasting
What are the 2 most common causes of fungal infections in cats?
- Cryptococcus
- histoplasma capsulatum
What life stage of Coccidioides immitis is inhaled and formed from mycelium?
Arthroconidia
Where is coccidioides immitis endemic?
Southwest
What fungal pathogen can manifest as osteomyelitis or respiratory disease?
Coccidioides immitis
What characteristic can be observed microscopically in a coccidioides immitis infection?
spherules containing endospores within the tissue
What is the microscopic characteristic feature of sporothrix schenkii?
Cigar-shaped, elpongated, pleomorphic yeast within tissue
What fungal pathogen is also known as Rose Gardner’s syndrome and causes lymphatic granuomatous lesions in cats and horses?
Sporothrix schenkii
What type of fungal pathogen is ubiquitous in “moldy environemnts”
Asperigillus
What fungal pathogen is known to cause a leathery skin pattern on aborted fetuses, air sacculitis, rumenititis, sinusititis, and gutteral pouch mycosis?
Asperigillus
What pathogen is spread by algea in warm environments?
Prototheca
WHat disease is caused by Pseudogymnoascus destructans?
White-nose syndrome
What disease is caused by Rhinosporidium seeberi in mammals and birds
Nasal polyps