B3-088 Fungal Infections Flashcards
cell wall membrane of fungi contains
ergosterol
single celled fungi
yeast
multicellular hyphae
mold
tube like outgrowth that is the beginning of a hypha
germ-tube
[yeast] chain of cells produced when buds fail to disassociated
sausage like
pseudohyphae
[yeast and mold] long, branching filamentous-like structure that fungi use for vegetative growth
hypha
[yeast] fungal spores produced by segmentation/breakup of hyphae
barrel shaped or rectangular
arthroconidia
[mold] mat or mass of hyphae
mycelium
[mold] sac like structure
sporangium
[mold] produced sexually of asexually within sporangium
spores
[mold] stalk bearing sporangium
sporangiophore
[mold] asexual; not enclosed in sac
conidium
[mold] specialized hyphal stalk on which condida are formed
condidiophore
[mold] enlarged, thick walled, contains stored food
chlamydoconidium
containing no pigment
hyaline
containing a dark melanin pigment
dematiaceous
fungus with the ability to obtain nutrients from keratin and infect skin
dermatophyte
having two distinct forms; temperature dependent changes
dimorphic
microsporum
trichophyton
epidermophyton
are what type of fungi?
dermatophytes
dermatophytes cause
ringworm
nail infection caused by any fungus
onychomycosis
dermatophytes commonly infect [group of people]
athletes
gyms, locker rooms
are dermatophytes highly contagious?
yes
ring appearance on skin
dermatophyte
discolored, thick, or crumbling nails
dermatophyte
may impact skin pigmentation
dermatophyte
diagnosis is primarily based on appearance of the skin
dermatophyte
dissolves the keratin material so the fungi can be seen better
KOH
Wood’s light can be used to help diagnose
tinea capitis
organisms rhizopus, mucor, rhizomucor cause
mucormycosis
found in bread molds
mucormycosis
mucormycosis is transmiteed via
inhalation of spores
major risk factor for mucomycosis
DKA
**also immunosuppressed and IV drug users
mucormycosis has a __________ mortality
very high
infects pulmonary, rhinocerebral, and cutaneous areas
mucormycosis
mucormycosis is diagnosed via
culture/direct exam
the hyphae of mucormycosis have a ________ angle
wide
**sketchy tire irons
mucomycosis colonies are __________
wooly
aspergillus fumigatas causes
most cases of invasive disease
aspergillus niger causes
aspergilloma
aspergillus flavus causes
disease in leukemic patients
used to ferment rice and produce sake
aspergillosis
transmission of aspergillosis
inhalation; traumatic implantation
neutropenia, corticosteroids, and cytotoxic drugs are risk factors for
aspergillosis
the hyphae of aspergillosis have an _________ angle
acute angle
**differentiating from mucormycosis
type I hypersensitivity reaction caused by aspergillosis
allergic bronchopulmonary aspergillosis
allergic bronchopulmonary aspergillosis is seen in what patient population?
CF and asthma
lung tissue is destroyed, cavities form that can lead to fungus balls
chronic pulmonary aspergillosis
chronic pulmonary aspergillosis is seen in what patient populations
immunocompromised w/
TB, sarcoidosis, bronchiectasis, emphysema
systemic aspergillosis occurs in
severely immunocompromised persons
galactomanna detection
aspergillosis
normal flora of skin in GI tract, GU tract, oropharyngeal tract
candidiasis
infections are endogenous in origin, caused by a breakdown in mucosal membrane
candidiasis
neutropenia
AIDS
abdominal surgery
prolonged antibiotics
immunosuppressants
IV catheters
long ICU stays
parental nutrition
risk factors for
candidiasis
culture shows white with rapid growth and “feet”
candidiasis
C. albicans produces a _______ within 2-3 hours of incubation
germ tube
C. glabrata rapidly produces _______
trehalose (RAT test)
common cause of “itis”s
candidiasis
identified via germ tube test or RAT test
candidiasis
transmission cryptococcosis
inhalation
dissemination to blood, CNS, bone marrow, skin, bone
cryptococcosis
HIV
lymphoproliferative malignancies
sarcoidosis
DM
transplant
corticosteroids
risk factors for
cryptococcosis
thick capsule that leaves a halo appearance with India Ink test
cryptococcosis
number one cause of fungal menigitis
cryptococcosis
cryptococcosis is diagnosed via
lateral flow/latex agglutination
causes focal pneumonitis, leading to acute respiratory failure
cryptococcosis
pneumocystis is transmitted via
inhalation
AIDS defining illness
pneumocystis jiroveci
pneumocystis lacks ______ in cell wall
ergosterol
**not susceptible to amphotericin B
causes interstitial pneumonia; alveoli filled with foamy exudate; impairs gas exchange
pneumocystis
calcofluor white stain cysts
pneumocystis
non-budding, clusters w/ intracystic bodies (double-comma)
pneumocystis
crushed ping pong balls on GMS
pneumocystis
foamy exudate on H&E
pneumocystis
blastomyces
histoplasma
coccidioides
paracoccidioides
talaromyces
sporothix
are all
dimorphic
dimorphic organism are generally ______ in environmental temperatures and _____ at body temperature
mold; yeast
dimorphs are transmitted via
inhalation of conidia [mold]
Ohio and Mississippi River Valley and SE
blastomycosis
moist soil, decomposing leaf/wood, lakes, ponds
blastomycosis
clinical symptoms can include:
asymptomatic
ARDS
cutaneous lesions
CNS, bone
blastomycosis
broad based budding, thick walled, refractile
blastomycosis yeast form
septate hyphae, conidiophore+condida=lollipop
blastomycosis mold form
Ohio and Mississippi river Valley and midwest
histoplasmosis
bat guano, bird droppings
histoplasmosis
histoplasmosis is transmitted via
inhalation of microconidia, spread via the lymphatic system
clinical presentation:
asymptomatic
acute/chronic pulmonary infection
disseminates to CNS, skin, GI
reactivation possible
histoplasmosis
narrow budding
histoplasmosis yeast form
tuberculate macroconidia+round microcondidia
histoplasmosis mold form
San Joaquin valley
SW US
coccidioides
occurs during the dry season, disappears in wet months
coccidioides
coccidioides transmission
inhalation of spores
barrel shaped arthroconidia are produced
coccidioides
coccidioides is dimorphic, but takes a ___________ form in humans
spherule (filled with endospores)
Valley Fever pneumonia
coccidioides
mexico, central/south america
but cases have also been seen in every state in the US
sporothrix
found in soil, decaying vegetation, rose buses, thorns, sphagum moss
sporothrix
transmission sporothrix
aerosolization or traumatic implantation
elongated, cigar shaped
sporothrix yeast form
clusters on conidia [rosette] at conidiophore
sporothrix mold form
rose gardner’s disease
sporothrix
lesion forms after inoculation, then ulcerates
sporothrix
then spreads via lymphatics
may mimic TB in pulmonary symptoms
sporothrix
disseminated sporothix causes
systemic symptoms, meningitis
central/south America (except Chili)
Brazil, venezuela, columbia, ecuador, argentina
paracoccidioides
transmission paracoccidioides
inhalation of conidia
being a male in agricultural work is a risk factor for
paracoccidioides
causes ulcerative mucocutaneous lesions
paracoccidioides
slowly progressive >30 years
paracoccidioides
lymphadenopathy, CNS, adrenal gland involvement
paracoccidioides
septate, branched chlamydospores
paracoccidioides mold form
mariner’s wheel
paracoccidioides yeast form
southeast asia, china, eastern india
talaromycosis
associated with bamboo rat
talaromycosis
talaromycosis transmission
inhalation of conidia
dissemination of blood, bone marrow, organs
talaromycosis
AIDS defining illness
talaromycosis
clinical features:
skin lesions
multiple organ involvement
respiratory failure
circulatory collapse
talaromycosis
diffusible red pigment, paint-brush like morphology
talaromycosis mold form
fission, central septum
talaromycosis yeast form