MYCO & VIROLOGY L4 (Midterms- Yeast) Flashcards
Yeast :P
Incidence of Yeast infection has escalated due to the increasing?
Immunosuppression among patients
TRUE OR FALSE: Cutaneous infections may be extremely aggressive and difficult to treat
**FALSE. Should be Yeast infection
Coined term for those not capable of sexual reproduction
Yeast-like
Able to reproduce sexually
Yeast
Often part of microbiota
Agents Yeast Infection
Generally, yeast reproduce asexually which is through the ____________ but they can also reproduce sexually through ___________
blastoconidia; ascospores and basidiospores
Enumerate at least three general characteristics of a Yeast
- Eukaryotic
- Unicellular organism
- Round to oval
- Size: 2-60 um
- Reproduce asexually by budding (blastoconidia)
Enumerate the characteristics for differentiation of yeasts
- Cell size
- Presence and absence of capsule
- Budding base (broad, narrow)
TRUE OR FALSE: Differentiation of yeasts in direct microscopic and histopathologic examination of clinical specimen is often impossible.
TRUE
An outpouching of the cell wall that becomes tubular and does not have a constriction at its base
Germ Tube
Buds elongate, fail to dissociate, and form subsequent buds; resemble links of sausage
Pseudohyphae
Have cell wall constrictions rather than true intracellular septation delineating the fungal cell border
Pseudohyphae
It represents the initial stage of true hyphae formation
Germ Tube
Macroscopically, it appears moist, creamy, may have bright pigments, and is either hyaline/melanized
Yeasts
Yeasts may produce a capsule resulting in a ______ or ________ colonial appearance
shiny; mucoid
Responsible for the most commonly encountered opportunistic fungal infections
Candida spp.
Fourth most common cause of hospital acquired bloodstream infections (BSI)
Candida spp.
Mortality rate of Candida spp. is as high as?
50%
The most commonly isolated yeast
C. albicans
An infection of the mucous membranes in the mouth, is considered a localized infection
Thrush (caused by Candida spp.)
Thrush can be seen in?
newborns and patients with HIV
These are once believed to not cause a disease
Non-Albicans Candida
Common urinary isolate, resistant to antifungal drugs, infections include endocarditis and meningitis, and is higher in older adults than in young adults and children
C. glabrata
C. glabrata can be differentiated from C. albicans through?
sugar (trehalose) assimilation
Seen in neonates and the second common cause of positive blood culture
C. parapsilosis
This organism is positive (+) for Germ tube
C. albicans
Microscopically, it reveals budding yeast cells, 2-4 um in diamater
Non-Albicans Candida