BIO205 Fungus and Fungal Diseases

Are fungi eukaryotic or prokaryotic

They are eukaryotic with a cell wall

What is the cell wall of fungi typically composed of

Chitin

What does chemoheterotrophic mean

It is how fungi get energy; they use chemical energy and get carbon from organic molecules

What are fungi composed of

Molds and yeasts

What is the makeup of mold

Multicellular; contains hyphae; produce by sexual and asexual spores

What is the makeup of yeasts

Unicellular; produce asexually by budding; some produce sexual spores

What are positive impacts of fungi

Decompose dead organisms and recycle their nutrients, produce antibiotics, and important to research tools

What are negative impacts of fungi

Cause 30% of diseases and can spoil fruit, pickles, jams, and jellies

What is the morphology of yeast

Single cell; small and globular

What is the morphology of molds

Multicellular; long branched tubular filaments

What are hyphae

Long branched tubular filaments

What does septate mean

Fungal filaments are divided into individual compartments

What does aseptate mean

Fungi that has no individual compartments, it is one continuous cell

What are dimorphic fungi

Fungi that produce both yeastlike and moldlike forms

What are dimorphic fungi responsible for

Most pathogenic fungal diseases

What does mycoses mean

They are fungal infections

What do the four true pathogenic fungi have in common

They are all dimorphic

What does mycelium mean

It is the mass of threadlike fungal filaments that together form the main body of a fungus and absorb nutrients.

What are the reproductive fruiting structures of molds

Puffballs or “mushrooms”

How do fungi reproduce

Asexually

How do yeasts reproduce

They use budding

How do molds reproduce

By using spore formation

How are spores categorized

They are categorized based on their development

What do asexual spores do for lab techs

It helps them ID fungal pathogens

What are two types of spores

Sporeangiospores and conidiophores

What media does fungus grow best on

Sabouraud dextrose agar

What is the difference between sporangiospores and conidiospores

Sporangiospores are inside the sac while conidiospores are on the outside

Why do people experience mycosis (fungal infection)

Fungi and their spores are almost everywhere in the environment

How do people get mycosis in their system

Through inhalation, trauma, or ingestion, or person-to-person contact

What is the exception of non-contagious fungi

Dermatophytes are contagious because they are on the skin

What are the categories of fungus

True fungal pathogens, opportunistic fungi, and fungal location in the body

How can we classify fungal infection for humans

We can classify them based on where they are located on the human body

What are the three categories of clinical manifestation

Fungal infections, toxicoses, and allergies

What is fungal infections classification defined as

Most common mycoses and either true pathogens or opportunistic pathogens

What is the category of toxicoses defined as

Mycoses acquired through ingestion and occurs when poisonous mushrooms are eaten

How are fungal allergies caused

Most often the result of inhalation of fungal spores

What are the characteristics of true fungal pathogens

Have the ability to actively attack and invade tissues, exhibit dimorphism, and endemic to certiain regions, primarily in the americas

What is a Sabouraud dextrose agar

The media that fungi grows best on

What is potassium hydroxide (KOH) preparations

Process that dissolved keratin in skin and biopsy, leaving the fungal cells

What are GMS stains

A staining technique used to stain only fungal cells; other cells are unstained

Why could anti fungal therapies be harmful to humans

They biochemistry is similar to human cells and antifungal drugs can harm human tissues

What is Amphoterecin B

The “gold standard” of antifungal treatments but also the most toxic

What do azole drugs do

They block ergosterol synthesis

What do opportunistic infection treatment require

High-dose treatment and long-term maintenance therapy

What does high-dose treatment so

It eliminates or reduces the fungal pathogens

What does long-term maintenance therapy do

It controls and prevents reinfection

Why do fungal pathogens cause harm

They cause infections throughout the body

What are the 4 pathogenic fungi

Blastomyces, coccidiodes, histoplasma, and paracoccidioides

What do the 4 pathogenic fungi have in common

They are all dimorphic

What are shared characteristics of fungal pathogens

They are acquired through inhalation and begin as a generalized pulmonary infection

What fungi causes blastomycosis

Caused by blastomyces

How is blastomycosis transmitted

Found in rich soils in organic matter; inhalation of dust can carry fungal spores into lungs

What is the most common fungal manifestation in humans

Pulmonary blastomycosis

How can blastomycosis be treated

Can be treated by amphotericin B (more severe) of Azole (more moderate)

What is coccidiomycosis also called

Valley fever

What fungal pathogen causes coccidiomycosis

Caused by coccidioides

How is coccidiomycosis transmitted

Transmitted through inhalation of dust that can carry the spores into the lungs

What are symptoms of blastomycosis

Symptoms can be fever, cough, night sweats, muscle pain, joint pain, chest pain, and fatigue

What are symptoms of coccidiomycosis

Symptoms can be fatigue, cough, dyspnea, headache, night sweats, muscle pain, and rash

What can coccidiomycosis be treated with

Can be treated with amphotericin B or azole

What causes histoplasmosis

Caused by histoplasma

What is the most common fungal pathogen affecting humans

Histoplasmosis is the most common

How is histoplasmosis transmitted

Transmitted by inhalation after disturbance of contaminated material (activities such as cleaning caves)

What are symptoms of histoplasmosis

Symptoms can be fever, cough, headache, chest pain, chills, and muscle pain

How is histoplasmosis treated

Treated with amphotericin B or azole

What causes paracoccidioidomycosis

Caused by paracoccidioides

How is paracoccidioidomycosis transmitted

Transmitted from inhalation of fungal spores from the environment

What are opportunistic infections

They are infections typically limited to people with poor immunity

What are the 5 typical opportunistic infection genera

Aspergillus, Candida, Cryptococcus, Pneumocystis, and Mucor

What causes asperigillosis

Caused by Asperigillus

How is aspergillosis transmitted

Transmitted by the inhalation of fungal spores

What causes candidiasis

Caused by Candida

How is candidiasis transmitted

Transmitted through individuals

How is candidiasis treated

Treated with azole

What causes dermatophytoses

Caused by dermatophytes

How is superficial mycoses transmitted

Transmitted through direct contact with fungus

How is dermatophytoses treated

Treated with a topical antifungal agent

What is tines pedis (athletes foot)

Common dermatophytoses; red raised lesions on and around the toes and soles of feet

What is tinea cruris (jock itch)

Common dermatophytoses; red, raised lesions around the groin and buttocks

What is tinea unguium

Common dermatophytoses; patches or pits on the nail surface

What is tinea corporis

Common dermatophytoses; red, raised, ring-like lesions occurring on various skin surfaces

What is tinea capitis

Common dermatophytoses; fungus developed on the outside of hair shafts which destroys the cuticle