Deck 58: Hyaline Molds, Zygomycetes, Dermatophytes, and Opportunistic and Systemic Mycoses

Question 1

Which genus is involved in infections of the skin and nails only?

A)Microsporum
B)Epidermophyton
C)Trichophyton
D)Scopulariopsis

Answer 1

B
The genus Trichophyton is capable of invading the hair,skin,and nails,whereas the genus Microsporum involves only the hair and skin;the genus Epidermophyton involves the skin and nails.

Question 2

MATCHING
Match the morphologic features with the dimorphic fungus.
a.Blastomyces dermatitidis
b.Coccidioides immitis
c.H.capsulatum
d.Paracoccidioides brasiliensis
e.Talaromyces marneffei
f.Sporothrix schenckii
Budding yeast resembling a "mariner's wheel"

Answer 2

D

Question 3

An organism was isolated after growing 26 days.Colonial morphologic appearance revealed heaped,wrinkled,moist,and yeastlike colonies.As the culture aged,colonies became covered with short aerial mycelium that turned from tan to brown.This organism is most likely:

A)Blastomyces dermatitidis.
B)Coccidioides immitis.
C)Histoplasma capsulatum.
D)P.brasiliensis.

Answer 3

D
Colonies of P.brasiliensis grow very slowly (21 to 28 days)and are heaped,wrinkled,moist,and yeastlike in appearance.With age,colonies may become covered with a short aerial mycelium and turn from tan to brown.The surface of colonies is often heaped with crater formations.

Question 4

MATCHING
Match the morphologic features with the dimorphic fungus.
a.Blastomyces dermatitidis
b.Coccidioides immitis
c.H.capsulatum
d.Paracoccidioides brasiliensis
e.Talaromyces marneffei
f.Sporothrix schenckii
Nonbudding,thick-walled spherule

Question 5

MATCHING
Match the morphologic features with the dimorphic fungus.
a.Blastomyces dermatitidis
b.Coccidioides immitis
c.H.capsulatum
d.Paracoccidioides brasiliensis
e.Talaromyces marneffei
f.Sporothrix schenckii
Small,round-to-oval yeast cells;2 to 5 µm in diameter

Question 6

A hair perforation test is performed using Trichophyton mentagrophytes and T.rubrum.The expected results are:

A)positive for both organisms.
B)positive for T.rubrum and negative for T.mentagrophytes.
C)positive for T.mentagrophytes and negative for T.rubrum.
D)negative for both organisms.

Question 7

MATCHING
Match the morphologic features with the dimorphic fungus.
a.Blastomyces dermatitidis
b.Coccidioides immitis
c.H.capsulatum
d.Paracoccidioides brasiliensis
e.Talaromyces marneffei
f.Sporothrix schenckii
Yeastlike cells with internal cross walls

Question 8

The term used to describe ringworm of the nail is:

A)Tinea cruris.
B)Tinea pedis.
C)Tinea capitis.
D)Tinea unguium.

Question 9

Which dermatophyte usually fluoresces yellow-green under a Wood's lamp?

A)Microsporum gypseum
B)Trichophyton verrucosum
C)Microsporum audouinii
D)Epidermophyton floccosum

Question 10

MATCHING
Match the morphologic features with the dimorphic fungus.
a.Blastomyces dermatitidis
b.Coccidioides immitis
c.H.capsulatum
d.Paracoccidioides brasiliensis
e.Talaromyces marneffei
f.Sporothrix schenckii
Single bud connected to the parent cell by broad base

Question 11

MATCHING
Match the morphologic features with the dimorphic fungus.
a.Blastomyces dermatitidis
b.Coccidioides immitis
c.H.capsulatum
d.Paracoccidioides brasiliensis
e.Talaromyces marneffei
f.Sporothrix schenckii
Cigar-shaped yeast cells

Question 12

Which rapidly growing Aspergillus spp.(2 to 6 days)best describes a mold that produces a fluffy-to-granular,white-to-blue green colony?

A)A.niger
B)A.flavus
C)A.fumigatus
D)A.terreus

Question 13

Which two assays should be used together for detecting antibodies toward B.dermatitidis,H.capsulatum,and C.immitis?

A)Enzyme-linked immunosorbent assay (ELISA)and direct fluorescent antibody (DFA)
B)Complement fixation and immunodiffusion
C)Indirect fluorescent antibody (IFA)and Western blot
D)Enzyme immunoassay (EIA)and latex agglutination

Question 14

A pulmonary fungus ball and external otomycosis and onychomycosis are all infections caused by which genera?

A)Fusarium
B)Penicillium
C)Paecilomyces
D)Aspergillus

Question 15

Trichophyton schoenleinii causes a condition that is characterized by the formation of yellowish cup-shaped crusts or scutulae,considerable scarring of the scalp,and sometimes permanent alopecia.This organism is usually recovered in _____ days.

A)5 to 7
B)14
C)21
D)30

Question 16

Which organism produces mostly shades of green or blue-green colonies? Microscopically,hyphae are hyaline and septate and produce brushlike conidiophores.

A)Paecilomyces
B)Acremonium
C)Scopulariopsis
D)Penicillium

Question 17

Which of the following Trichophyton spp.grows slowly (14 to 30 days)and best at 35°C to 37°C? In addition,enriched media with thiamine and inositol enhance its growth.

A)Trichophyton verrucosum
B)Trichophyton tonsurans
C)T.rubrum
D)T.mentagrophytes

Question 18

A fungus is recovered from a nail scrapping.Microscopic examination reveals numerous smooth,thin-walled,club-shaped,multiseptate macroconidia;however,microconidia are absent.The organism can be identified as:

A)Microsporum canis.
B)E.floccosum.
C)T.rubrum.
D)M.gypseum.

Question 19

The slow-growing organism Trichophyton rubrum produces a flat or heaped-up colony,generally white to reddish with a cottony or velvety surface.The cherry-red color is best observed on the reverse side of the colony.This organism is capable of infecting which of the following?

A)Hair and nails
B)Skin and nails
C)Hair and skin
D)Hair,skin,and nails

Question 20

Unbranched sporangiophores with rhizoids that appear opposite the point where the stolon arises at the base of the sporangiophore best describes which zygomycetes?

A)Mucor
B)Rhizopus
C)Lichtheimia
D)Absidia