Quiz 5 (yeasts and molds)

yeast and molds

What are the two forms of fungi?

yeasts and molds

Fungi that exhibit both yeast and mold phases are called, what?

dimorphic

How to yeasts reproduce?

via budding

Mold morphology includes

cottony or fuzzy growth

yeast structures include

* bud
* vacuole
* mitochondrion
* nucleus
* capsule
* cytoplasmic membrane
* cell wall

Structure of molds include

* Conidia
* sterigma
* Conidiophor
* Hypha
* Septum
* Nuleus
* Cell wall
* Sporangium
* Apophysis
* Sporangiophore
* Sporangiospores

How are fungal infections obtained?

breaks in the skin and inhalation of spores

T/F: fungal infections can be transmitted via person to person

False

Superficial (cutaneous) mycoses

are infections confined to the outermost layer of the skin and/or hair.

Symptoms include itching, scaling, or ringlike patches of the skin; brittle, or broken hairs; and thick, discolored nails.

Subcutaneous mycoses

involve the deeper skin layers, including muscle and connective tissue.

Symptoms include nonhealing ulcers and the presence of draining sinus tracts.

Systemic mycoses

are those infections that affect internal organs or deep tissues of the body. Often the initial site of infection is the lung. The organisms then gains entry into the bloodstream and disseminates to other organs.

Symptoms include fever, fatigue, chronic cough, and chest pain.

What is responsible for infections involving the superficial areas of the body?

Dermatophytes

Trichophyton sp. infects

hair, skin, nails

Microsporum sp. infect

hair and skin

Epidermophyton sp. infect

skin and nails

dermatophytes infect skin hair and nails for what reason?

* to use keratin as a nitrogen source

What is the most common cause of fungal infections of the feet and nails?

Trichophyton sp.

Diagnosis of dermatophytes includes:

* diagnosis from cultivation from scrapings
* Microscopic observation of structures

Cultivation of fungi uses media containing gentamicin and/or chloramphenicol why

prevent bacterial growth

Dermatophyte tests indicate a positive after 4 weeks, what is a positive

turning yellow to red within 14 days

Opportunistic mycoses

mycoses that occur most commonly in immunocompromised patients

Aspergillus species infect via

inhalation

Fusarium sp. cause

mycotic keratitis from traumatic implantation into the cornea. Can be detected in blood

Geotrichum sp. found in

wound infections and oral thrush

Acremonium sp found in

subcutaneous lesions, esophagitis.

Penicillium sp. found in

bronchopulmonary penicilliosis, allergic sinusitis.

Paecilomyces sp. found in

endophthalmitis, cutaneous \n infections, arthritis, endocarditis.

Fungi are diagnosed with

\n stains and cultivation, antigenic assay (high risk- aspergillosis), no PCR