MICRO 401 EXAM 4, FUNGAL PATHOGENS STUDY
GUIDE
Fungi basics - Answers - -cell wall containing chitin and glucan polymers
-unaffected by antibacterials
-ergosterol is the primary membrane sterol (cholesterol in mammals)
-have a cytosine deaminase (C->U) not present in mammals
Azoles - Answers - Class of antifungals that inhibit ergosterol synthesis
Polyenes - Answers - Class of antifungals that interact with ergosterol, causing pores
and cell leakage
Allylamines - Answers - Class of antifungals that inhibit ergosterol synthesis
Echinocandins - Answers - Class of antifungals that disrupt cell wall glucan synthesis
Fungal sex - Answers - Can reproduce a/sexually
-timing/frequency varies by species
-maintains pathogenicity
4 fungal classifications by sexual spores - Answers - -ascomycetes
-basidiomycetes
-zygomycetes
-deuteromycetes (no spores)
Fungal classifications - Answers - By:
-sexual spores
-appearance/morphology
-yeast/hyphae/pseudohyphae
-thermal dimorphism
Mycobiome - Answers - The resident fungi on the human body
-may contain opportunistic pathogens
-changes based on host immune status
Dermatophyte fungi - Answers - Keratinolytic (use keratin for energy)
-cause ringworm ("tinea"), may be transmitted by pets
Tinea capitis - Answers - ringworm of the scalp
Tinea corporis - Answers - ringworm of the body
, Tinea cruris - Answers - ringworm of the groin, jock itch
Tinea pedis - Answers - ringworm of the foot, athlete's foot
Pityriasis versicolor - Answers - Superficial epidermis infection by Malassezia spp.
-common in sebaceous gland rich regions
-more common in tropical climates
-topical antifungal treatment
Malassezia spp. - Answers - Causes pityriasis versicolor
-dermophilic and lipophilic
-dimorphic (yeast and hyphae forms)
Malassezia spp. and Chron's - Answers - Present in the gut of Chron's patients
-CARD9 risk allele associated with higher levels of gut Malassezia spp.
-CARD9 is involved in immune signalling against fungi, hyperactive in Chron's
Onychomycosis - Answers - Fungal nail infection
-caused by dermatophytes
-treated with nail lacquers
Tinea unguium - Answers - ringworm of the nails, aka onychomycosis
Systemic mycoses - Answers - Opportunistic and primary fungal pathogens
Opportunistic fungi - Answers - Growing prevalence due to new susceptible population
(more cancer patients, organ transplants, HIV)
Candida species - Answers - Form yeast/hyphae/pseudohyphae
-normal flora, can colonize GI and GU tracts
Muco-cutaneous candidasis - Answers - Overgrowth of normal candida flora
-limited to lining surfaces, may result from antibiotic use
Disseminated candidiasis - Answers - Invasion of candida into tissue, bloodstream
-May result from leaky gut, catheters, physical breech
-bloodstream infections are common
-presents as nonspecific sepsis
-treated by removal of catheters, antifungals
Oral thrush - Answers - Oral candida infection
Candida auris - Answers - Multi drug resistant emerging fungal pathogen
-nursing homes and hospitals
GUIDE
Fungi basics - Answers - -cell wall containing chitin and glucan polymers
-unaffected by antibacterials
-ergosterol is the primary membrane sterol (cholesterol in mammals)
-have a cytosine deaminase (C->U) not present in mammals
Azoles - Answers - Class of antifungals that inhibit ergosterol synthesis
Polyenes - Answers - Class of antifungals that interact with ergosterol, causing pores
and cell leakage
Allylamines - Answers - Class of antifungals that inhibit ergosterol synthesis
Echinocandins - Answers - Class of antifungals that disrupt cell wall glucan synthesis
Fungal sex - Answers - Can reproduce a/sexually
-timing/frequency varies by species
-maintains pathogenicity
4 fungal classifications by sexual spores - Answers - -ascomycetes
-basidiomycetes
-zygomycetes
-deuteromycetes (no spores)
Fungal classifications - Answers - By:
-sexual spores
-appearance/morphology
-yeast/hyphae/pseudohyphae
-thermal dimorphism
Mycobiome - Answers - The resident fungi on the human body
-may contain opportunistic pathogens
-changes based on host immune status
Dermatophyte fungi - Answers - Keratinolytic (use keratin for energy)
-cause ringworm ("tinea"), may be transmitted by pets
Tinea capitis - Answers - ringworm of the scalp
Tinea corporis - Answers - ringworm of the body
, Tinea cruris - Answers - ringworm of the groin, jock itch
Tinea pedis - Answers - ringworm of the foot, athlete's foot
Pityriasis versicolor - Answers - Superficial epidermis infection by Malassezia spp.
-common in sebaceous gland rich regions
-more common in tropical climates
-topical antifungal treatment
Malassezia spp. - Answers - Causes pityriasis versicolor
-dermophilic and lipophilic
-dimorphic (yeast and hyphae forms)
Malassezia spp. and Chron's - Answers - Present in the gut of Chron's patients
-CARD9 risk allele associated with higher levels of gut Malassezia spp.
-CARD9 is involved in immune signalling against fungi, hyperactive in Chron's
Onychomycosis - Answers - Fungal nail infection
-caused by dermatophytes
-treated with nail lacquers
Tinea unguium - Answers - ringworm of the nails, aka onychomycosis
Systemic mycoses - Answers - Opportunistic and primary fungal pathogens
Opportunistic fungi - Answers - Growing prevalence due to new susceptible population
(more cancer patients, organ transplants, HIV)
Candida species - Answers - Form yeast/hyphae/pseudohyphae
-normal flora, can colonize GI and GU tracts
Muco-cutaneous candidasis - Answers - Overgrowth of normal candida flora
-limited to lining surfaces, may result from antibiotic use
Disseminated candidiasis - Answers - Invasion of candida into tissue, bloodstream
-May result from leaky gut, catheters, physical breech
-bloodstream infections are common
-presents as nonspecific sepsis
-treated by removal of catheters, antifungals
Oral thrush - Answers - Oral candida infection
Candida auris - Answers - Multi drug resistant emerging fungal pathogen
-nursing homes and hospitals
