what is a mycosis
fungal infection
what is a mushroom
a fruiting body full of hyphae with a chitin-based cell wall
distinguishable from the cholesterol in our bodies
how are fungi the source of allergens and toxins (mycotoxicosis)
due to aflatoxin that causes Liver cancer
what are the 4 true human fungal pathogens
Histoplasma sp
Blastomyces sp
Coccidiodes sp
Paracoccidiodes sp
what are true human fungal pathogens
attacks and infects individuals that are totally immunocompetent
they display thermal dimorphism
what is the most common systemic true pathogens
Histoplasma sp : histoplasmosis
What is the most virulent systemic true pathogen
Coccidiodes sp: coccidiodomycosis
how does the warm form of true human fungal pathogens spread
Parasitic yeast phase at 35–40 °C; divides fast, reproduces through budding/endospores, and disseminates through the body.
how does the environmental form of true human fungal pathogens spread
Free-living (saprobic) mycelial phase in the environment at cool temperatures (<30 °C); undergoes sporulation, and the spores spread through wounds
how do systemic true pathogens usually get into the body
via respiratory system by inhaling spores or other fungal material
No Human-Human spread
where does Histoplasmosis grow
animal fecal matter that is nitrogen rich
how would Histoplasmosis and Blastomycosis enter the body
filamentous hyphae grow spores that can become airborne
enters the warm lung, transforms dimorphically to yeast form, goes into Lymphatic system, connects to blood, to rest of body
what distinguishes Histoplasmosis and Blastomycosis
microcinidia (small infectious spores) found in histoplasmosis but not in blastomycosis
how does Coccidioidomycosis transmit
warm, dry, salty areas
air picks up at least 1 arthrospore produced from broken hyphae
contains spherules: round cell that produces many spores that can spread in the body
what are the intermediate virulence pathogens
sporothrix sp: subcutaneous (more problematic by lymph)
Dermatophytes: Cutaneous
describe how intermediate virulence pathogens are diff than systemic true pathogens
more localized spread and infection
describe fixed sporotrichosis
lesion as a nodule that reddens then ulcerates then rests below the skin layer
describe lymphocutaneous sporotrichosis
goes through subcutaneous tissue into lymph nodes
where is sporothrix sp found in the environment
decaying plant materal
sick cats
why is Sporothrix sp unique
only thermal dimorphic fungus that does not use the pulmonary system as a major route of entry
how is sporothrix sp usually contracted
most infections are due to fungal spores entering a skin puncture wound
What are dermatophytoses
fungal infections that live on the surface of skin infecting nonliving epidermal tissue
What are the opportunistic mycoses
Candida sp
Cryptococcus sp
What is Cryptococcosis
A bird-feces related fungal infection that enters through respiratory system in the form of a fungal cell surrounded by a fungal capsule
