Mycology MCQs

8/11/2019 Mycology MCQs

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This organism grew on Sabouraud Dextrose agar without any antimicrobials. The

patient presented with onychomycosis of both great toenails. The nails were dark and

dystrophic, and thick scale was apparent on both feet. Identify the fungus.

1 Trichophyton rubrum

2 Microsporum distortum3 Scytalidium dimidiatum

4 Coccidioides immitis

5 Trichophyton violaceum

Q/Q(M)-474523 Report a Problem

This organism grew on Sabouraud Dextrose agar without any antimicrobials. The

patient presented with onychomycosis of both great toenails. The nails were dark and

dystrophic, and thick scale was apparent on both feet. Identify the fungus.

3 Scytalidium dimidiatum

This organism is inhibited by cycloheximide in artificial media. Clinically it appears

identical to a dermatophyte infection.


A biopsy shows broad-based budding thick walled yeast cells, 10-15 um with a

double contoured appearance.

1 This yeast has a yeast phase at room temperature

2 Does not grow at 37C

3 Usually produces a severe characteristic pulmonary disease

4 May be found in dogs

5 Is transmitted by mosquitoes


A biopsy shows broad-based budding thick walled yeast cells, 10-15 um with a

double contoured appearance.

4 May be found in dogs

This biopsy describes Blastomyces dermatitidis which generally can be found in

decaying vegetation but can be carried by dogs.

Q/Q(M)-474527 Report a ProblemSeptate hyphae with 90branching and thick walled barrel shaped arthroconidiaalternating with empty cells best describes the microscopic morphology of:

1 Histoplasma capsulatum

2 Sporothrix schenckii

3 Microsporum gypseum

4 Trichophyton tonsurans




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Septate hyphae with 90branching and thick walled barrel shaped arthroconidiaalternating with empty cells best describes the microscopic morphology of:


This is the only organism in this list that fits this description.

Q/Q(M)-474516 Report a ProblemA patient with scaly feet has a positive KOH. Fungal culture reveals smooth, club-

shaped macroconidia attached to hyphae in groups. No microconidida are seen. The

organism is:

1 Microsporum canis

2 Epidermophyton floccosum



5 Trichophyton tonsuransQ/Q(M)-477322 Report a Problem

A patient with scaly feet has a positive KOH. Fungal culture reveals smooth, club-

shaped macroconidia attached to hyphae in groups. No microconidida are seen. The

organism is:


The wet mount Epidermophyton floccosum shows smooth, thin-walled macroconidia

without microconidia. The appearance is occasionally referred to as snow shoes.Epidermophyton floccosum is incapable of hair invasion, and therefore, does not

cause tinea capitis.


Which of the following organisms will cause infections of skin, nails and endothrix

hair?


2 Microsporum audouinii

3 Trichophyton schoenlinii

4 Microsporum canis

5 Trichophyton mentagrophytes


Which of the following organisms will cause infections of skin, nails and endothrix

hair?

3 Trichophyton schoenlinii

E. floccosum does not infect hair; M. audouinii and M. canis cause fluorescent

ectothrix T. capitis, T. mentagrophytes ectothrix T. capitis.


An organism producing an apricot colored colony and reflexive branching with few

conidia was cultured from a patient from Africa. Which of the following is/are true?

1. This mostly likely is T. verrucosum 2. This most likely is T. soudanense 3. This


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most likely is T. violaceum 4. This organism causes endothrix tinea capitis 5. This

organism is zoophilic

1 1,5

2 2,4

3 2,4,5

4 3, 4

5 3, 4, 5


An organism producing an apricot colored colony and reflexive branching with few

conidia was cultured from a patient from Africa. Which of the following is/are true?

1. This mostly likely is T. verrucosum 2. This most likely is T. soudanense 3. This

most likely is T. violaceum 4. This organism causes endothrix tinea capitis 5. This

organism is zoophilic

2 2,4

T. soudanense produces an apricot colored colony with reflexive branching. It is an

anthropophilic organism causing an endothrix tinea capitis. T. verrucosum produces a

white colony and requires thiamine and inositol for sporulation, T. violaceum

produces a purple colony and has a partial requirement for thiamine


The most common cause of tinea capitis in the United States today is:

1 Trichophyton schoenleinii

2 T. tonsurans

3 T. mentagrophytes


5 M. canis


The most common cause of tinea capitis in the United States today is:

2 T. tonsurans

M. audouinii was previously the primary cause of T. capitis in the US.


The most sensitive microscopic test for fungal infection is:

1 Potassium Hydroxide

2 Potassium Hydroxide with DMSO

3 Chlorazol Black E

4 Calcofluor white

5 Swartz Lamkins stain


The most sensitive microscopic test for fungal infection is:


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4 Calcofluor white

Calcofluor white is the most sensitive microscopic test for fungal infection. It is a

glucan specific immunofluorescent stain. The remaining options are useful in direct

microscopic examination, but not the most sensitive.

Q/Q(M)-478218 Report a ProblemWhich two characteristics combined form a significant risk for acquiring

sporotrichosis? 1. Animal handler 2. Male gender 3. Alcoholism 4. Filipino or African

decent 5. Genetic predisposition

1 1, 2

2 1, 3

3 3, 4

4 4, 5

5 3, 4Q/Q(M)-474509 Report a Problem

Which two characteristics combined form a significant risk for acquiring

sporotrichosis? 1. Animal handler 2. Male gender 3. Alcoholism 4. Filipino or African

decent 5. Genetic predisposition

2 1, 3

A variety of domestic animals can carry Sporotrichosis. Alcoholism increases the risk

for this cutaneous infection.


Which of the following statements regarding dermatophyte infection FALSE?

1 Trichophyton schoenleinii is a common cause of favus

2 Microsporum canis is associated with ectothrix tinea capitis

3 Trichophyton violaceum is normally associated with endothrix tinea capitis

4Microsporum audouinii displays yellow fluorescence with Woods lampexamination

5 Trichophyton rubrum is always an ectothrix infection


Which of the following statements regarding dermatophyte infection FALSE?

5 Trichophyton rubrum is always an ectothrix infection

Organisms that cause an ectothrix pattern of tinea capitis include M. canis, M.

audouinii, M. ferruginosum, M. distortium, M. gypseum and occasionally T. rubrum.

T. tonsurans, T. violaceum, T. soudanense, T. gourvilli, T. yaoundei, and occasionally

T. rubrum cause an endothrix pattern. T. schoenleinii causes favus in which hyphae

and air spaces are seen in the hair shaft. A bluish-white fluorescence pattern is seen

with Woods lamp. Clinically, patients have thick, yellow, cup-shaped crusts(scutula); scarring and secondary infection may result. M. canis, M. audouinii, M.

ferruginosum, M. distortium display a yellow fluorescence on Woods lampexamination.



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The major endemic area for Histoplasmosis

1 Africa

2 Central America

3 Southwest United States

4 South America

5 Eastern United States


The major endemic area for Histoplasmosis

5 Eastern United States

The endemic area for Histoplasmosis includes: the Ohio, Mississippi and Missouri

River Valleys Syracuse NY area and the Caribbean. This organism prefers soil with a

high nitrogen content such as that enriched with bird and bat guano.

Q/Q(M)-474497 Report a ProblemWhich of the following is TRUE regarding coccidiomycosis?

1 First line treatment in pregnancy is itraconazole

2 Droplet transmission is the most common method of acquisition of disease

3 Southeast Asians are at a higher risk of disseminated disease

4 Erythema nodosum is associated with a poor prognosis

5 Approximately 75% of those contracting the disease will be symptomatic


Which of the following is TRUE regarding coccidiomycosis?

3 Southeast Asians are at a higher risk of disseminated disease

Southeast Asians and African Americans are at a higher risk for disseminated cocci,

as are pregnant women and the immunocompromised. Approximately 60% of those

contracting coccidiomycosis are asymptomatic, and the disease is infectious not

contagious. The most common method of disease acquisition is inhalation from the

soil during natural events (dust storms etc). Erythema nodosum is associated with a

good prognosis and the first-line treatment during pregnancy is amphotericin B.

(JAAD 2006 CME)


Which of the following organisms is most likely to cause a sporotrichoid nodule on

the arm:

1 Nocardia brasiliensis

2 Phialophora verrucosa

3 Rhinospiridium seeberii

4 Fusarium

5 Fonsecaea pedrosoi



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Which of the following organisms is most likely to cause a sporotrichoid nodule on

the arm:


Nocardia brasiliensis is a common cause of actinomycotic mycetoma and the

ulcerative, draining lesions can be misdiagnosed as sporotrichosis.Q/Q(M)-474510 Report a Problem

Culturing T. rubrum from a white opacity on the fingernail plate should prompt

testing for what?

1 Diabetes mellitus

2 Hypothyroidism

3 Hyperthyroidism

4 HIV

5 CirrhosisQ/Q(M)-476555 Report a Problem

Culturing T. rubrum from a white opacity on the fingernail plate should prompt

testing for what?

4 HIV

White superficial onychomycosis of the fingernails is a marker for immunosuppresion

and should prompt testing for HIV. Generally, T. mentag is the most common cause

of white superfical onychomycosis. However, in immunosuppressed patients, T.

rubrum is the more common dermatophyte.


Which of the following statements regarding mycelium is NOT true?

1 A mass of hyphae is mycelium

2 Mycelium has reproductive capability

3 Hyphae forming corkscrew-like turns are spiral hyphae

4 Pectinate bodies are hyphae resembling a comb

5 Racket forms are club-shaped cells


Which of the following statements regarding mycelium is NOT true?2 Mycelium has reproductive capability

Mycelium does not have reproductive capabilities. The remaining statements are

correct.


A pet store owner comes into your office with pruritic scaly plaques on his arms. A

fungal culture demonstrates a yellow colony with spindle-shaped macroconidia which

grows on polished rice grains. The organism is:

1 Microsporum canis



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3 Rhinosporidiosis

4 Pseudallescheriosis

5 Cryptococcosis


A 34-year-old male patient presents with a verrucous lesion of the nasal mucosa; the

biopsy showed spherules ranging in size from 200 to 325 um. The mature endospores

have a rough appearance. The diagnosis is:

3 Rhinosporidiosis

The large size of the spherule and the rough endospores describe this organism along

with the clinical symptoms. The other organisms that produce spherules are

Prototheca (8-20 um) and Coccidioides immitis (10-80 um)


A patient returns from a vacation in Brazil with keloidal-like nodules on the face andarms. The patient denies any sick contacts or exposures and reports only lying on the

beach and swimming with dolphins. She likely has:

1 Actinomycosis

2 Lobomycosis

3 Chromoblastomycosis

4 Mucormycosis

5 SporotrichosisQ/Q(M)-477329 Report a Problem

A patient returns from a vacation in Brazil with keloidal-like nodules on the face and

arms. The patient denies any sick contacts or exposures and reports only lying on the

beach and swimming with dolphins. She likely has:

2 Lobomycosis

Lobomycosis, also called Keloidal blastomycosis, is caused by Loboa loboi. Lesions

characteristically appear keloidal with or without fistulas. A common location for the

infection is on the ears and has been associated with dolphins. Histologically, double

contoured refractile spherules with budding may be seen.


Which of the following statements regarding superficial mycotic infections is TRUE?

1 Malassezia species do not fluoresce under a Woods lamp

2 Phaeoannellomyces wernecki causes tinea nigra

3 Trichophyton beigelii causes white piedra

4 Trichosporon hortae causes black piedra

5 Micrococcus sedentarius causes tinea nigra


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Which of the following statements regarding superficial mycotic infections is TRUE?

2 Phaeoannellomyces wernecki causes tinea nigra

Malassezia species fluoresce pale yellow with Woods lamp examination.Trichosporon beigelii (not trichophyton) causes white piedra, an infection that causes

tan to white, soft non-adherent concretions on head and pubic hairs. Piedraia hortae

causes black piedra, which forms dark concretions that are adherent to scalp, beard,

and pubic hairs. Micrococcus sedentarius is a bacterium that is responsible for pitted

keratolysis, which is characterized by crateriform pitting that primarily affects the

pressure-bearing aspects of the plantar surface of the feet and, occasionally, the palms

of the hands. Tinea nigra (superficial phaeohyphomycosis) presents with

asymptomatic brown to black, macular, non-scaly macules and patches on the palms

or soles. Phaeoannellomyces werneckii is causative.


The most reliable method for distinguishing between Trichophyton rubrum and T.

mentagrophytes is:

1 Morphology of microconidia

2 Morphology of macroconidia

3 Pigmentation studies

4 Hair perforation test

5 Colony morphology


The most reliable method for distinguishing between Trichophyton rubrum and T.

mentagrophytes is:

4 Hair perforation test

The diagnostic morphology of the Trichophytons overlap and may be difficult to

differentiate. T. mentagrophytes produces a positive hair perforation test (wedges in

the test hair).


A young girl presented with a scaly annular facial rash and alopecia of her lower

eyelashes. Which of the following statements is/are true? 1. A KOH prep and fungal

culture might confirm the diagnosis. 2. The etiologic agent might be Microsporum

canis. 3. The family puppy might be infected. 4. Griseofulvin would be the drug of

choice. 5. A topical azole cream would be the drug of choice.

1 1,2,4

2 1,2,3,4

3 1,3,4

4 1,2,5


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5 1,2,3,5


A young girl presented with a scaly annular facial rash and alopecia of her lower

eyelashes. Which of the following statements is/are true? 1. A KOH prep and fungalculture might confirm the diagnosis. 2. The etiologic agent might be Microsporum

canis. 3. The family puppy might be infected. 4. Griseofulvin would be the drug of

choice. 5. A topical azole cream would be the drug of choice.

2 1,2,3,4

KOH and culture are the best and most reliable lab tests to diagnose a fungal

infection. M. canis is frequently found in kittens and puppies and is a common cause

of tinea faciei in children. An oral antifungal should be prescribed when a fungal

infection involves hair.


This organism does not produce microconidia. The macroconidia are club shaped, andsmooth walled, they grow singly or in clusters.




4 Microsporum canis



This organism does not produce microconidia. The macroconidia are club shaped, and

smooth walled, they grow singly or in clusters.


This is the only organism in this list that fits this description.


Which of the following organisms causes favus?

1 Trichophyton schoenleinii2 Trichophyton mentagrophytes

3 Microsporum canis


5 Microsporum distortum


Which of the following organisms causes favus?1 Trichophyton schoenleinii


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Favus is a chronic dermatophyte infection defined by the presence of yellowish crusts

in the hair follicles called scutula. Prolonged infections lead to cicatricial alopecias of

the scalp and glabrous skin. The infection is most commonly caused by Trichophyton

schoenleinii.


Growth of which of the following is not inhibited on Mycosel media?

1 Cryptococcus neoformans

2 Yeast forms of Histoplasma

3 Yeast forms of Blastomyces


5 Scytalidium species


Growth of which of the following is not inhibited on Mycosel media?


Cycloheximide in Mycosel or Mycobiotic media (SDA with cycloheximide and

chloramphenicol) inhibits rapidly growing nonpathogenic molds and some pathogens

(Cryptococcus neoformans, some Candida species, Prototheca, Scytalidium species,

yeast forms of Histoplasma and Blastomyces).


This organism is the most common cause of eumycotic mycetoma in the US:

1 Madurella mycetomatis

2 Nocardia asteriodes

3 Scedosporium apiospermum


5 Wangiella dermatitis

This organism is the most common cause of eumycotic mycetoma in the US:

3 Scedosporium apiospermum

Although fairly uncommon, S. apiospermum is the most frequently recovered

organism causing eumycotic mycetoma in the US. This name represents the asexual

stage of the organism which grows as a filamentous mould, the sexual state,

Pseudallescheria boydii, grows as a cleistothecia (round sac containing ascospores).

A horticulturist of sphagnum moss topiaries comes in with a nodular eruption with

lymphangitic spread and treatment with oral potassium iodide is initiated. What is the

most well recognized side effect of this treatment.

1 Gastrointestinal distress


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2 Shortness of breath

3 Flushing

4 Angioedema

5 PruritusA horticulturist of sphagnum moss topiaries comes in with a nodular eruption with

lymphangitic spread and treatment with oral potassium iodide is initiated. What is the

most well recognized side effect of this treatment.

1 Gastrointestinal distress

This patient has sporotrichosis. Sporotrichosis is mainly an occupational disease of

farmers, gardeners, and horticulturists. Persons who handle thorny plants, sphagnum

moss, or baled hay are at increased risk. Outbreaks have occurred in nursery workers

who handled sphagnum moss, rose gardeners, children playing on baled hay, and

greenhouse workers who handled bayberry thorns contaminated by the fungus.

Classic treatment is with oral potassium iodide for 3-4 weeks. The most recognisedside effect of treatment is gastrointestinal distress. Thyroid function tests should be

performed during treatment as supppression can occur.


This organism produces an endothrix tinea capitis:



3 Microsporum nanum

4 Trichophyton verrucosum

5 Trichophyton soudanense


This organism produces an endothrix tinea capitis:


Only T. soudanense in this group of choices produces an endothrix type of tinea

capitis. Trichophyton mentagrophytes, Microsporum nanum and Trichophyton

verrucosum produce nonfluorescent ectothrix tinea capitis. Microsporum gypseum

may produce a fluorescent or nonfluorescent ectothrix tinea capitis.

Q/Q(M)-474063 Report a ProblemA blood culture from a neutropenic patient with onychomycosis grew which of the

following organism:

1 Scopulariopsis sp

2 Aspergillus sp

3 Fusarium sp

4 Acremonium sp

5 T. rubrum



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A blood culture from a neutropenic patient with onychomycosis grew which of the

following organism:

3 Fusarium sp

Fusarium is one of the few moulds, which yield positive blood cultures, neutropenia is

one of the risk factors for Fusariosis.Q/Q(M)-474907 Report a Problem

Which of the following causes "black dot ringworm"?

1 M. canis

2 T. violaceum

3 T. verrucosum

4 M. gypseum

5 M. auddouinii

Q/Q(M)-478131 Report a ProblemWhich of the following causes "black dot ringworm"?

2 T. violaceum

"Black dot ringworm" is endothrix tinea capitis. Black dots are remnants of brittle hair

broken at the surface of the scalp (cuticle intact). On KOH prep, spores are seen

within the hair shaft. Causes are T. rubrum, T. gourvilli, T. yaounde, T. tonsurans, T.

schoeleinii, T. soudanense, and T. violaceum ("Ringo Gave Yoko Two Squeaky

Violins."). T. verrucosum causes nonfluorescent ectothrix tinea capitis. M canis,

gypseum, and auddouinii also cause ectothrix tinea capitis.


Cutaneous lesions of Cryptococcosis may be 1. Nodular 2. Papular 3. Granulomatous-

ulcerative 4. Herpetiform 5. Cellulitis-like:

1 2, 3, 4

2 3, 4, 5

3 2, 3, 4

4 1, 3, 4, 5

5 All of these answers are correct


Cutaneous lesions of Cryptococcosis may be 1. Nodular 2. Papular 3. Granulomatous-

ulcerative 4. Herpetiform 5. Cellulitis-like:


Polymorphous lesions have been reported in Cryptococcosis


Sabouraud Dextrose Agar (SDA) Emmons Modification contains which of the

following?

1 Peptones

2 Phenol red


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3 Chloramphenicol

4 Gentamicin

5 Cycloheximide

Q/Q(M)-478108 Report a ProblemSabouraud Dextrose Agar (SDA) Emmons Modification contains which of the

following?

1 Peptones

SDA Emmons Modification is the gold standard medium. It is nutritionally poor,

containing dextrose, peptones, water, and agar, and encourages sporulation. Phenol

red, gentamicin, and cycloheximide are found in dermatophyte test media (DTM).

Chloramphenicol and cycloheximide are found in Mycosel/Mycobiotic.


Mycelia can form structures with a comb-lke appearance called:

1 Racket forms

2 Favic chandeliers

3 Pectinate bodies

4 Spiral hyphae

5 Nodular bodies


Mycelia can form structures with a comb-lke appearance called:

3 Pectinate bodiesRacket forms (club-shaped cells), favic chandeliers (terminal hyphal branches having

an antler-like appearance), pectinate bodies (hyphae resembling a comb), spiral

hyphae (hyphae forming corkscrew-like turns), and nodular bodies (knot-like

structure of hyphae) are among the types of mycelia.


Nondermatophytes growing on Dermatophyte Test Media cause the media to turn

what color?

1 Amber

2 Red

3 Yellow

4 Black

5 Green


Nondermatophytes growing on Dermatophyte Test Media cause the media to turn

what color?

3 Yellow

Dermatophytes utilize protein as a carbon source producing alkaline by-products

causing Dermatophyte Test Media to turn from amber to red. Nondermatophytes


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cause the media to turn yellow due to acid by-products.


Which of the following is not true regarding fungal culture media containing

cycloheximide?

1 Cycloheximide is not found in Sabouraud Dextrose Agar (SDA) EmmonsModification

2 Cycloheximide is found in Mycosel

3 Cycloheximide is found in Dermatophyte Test Media

4 Cycloheximide is found in Mycobiotic

5 Cycloheximide inhibits bacterial flora


Which of the following is not true regarding fungal culture media containing

cycloheximide?

5 Cycloheximide inhibits bacterial flora

Sabouraud Dextrose Agar (SDA) Emmons Modification does not contain

cycloheximide. Mycosel/Mycobiotic (SDA with cycloheximide and chloramphenicol)

and Dermatophyte Test Media contain cycloheximide. Cycloheximide inhibits rapidly

growing nonpathogenic molds and some pathogens (Cryptococcus neoformans, some

Candida species, Prototheca, Scytalidium species, yeast forms of Histoplasma and

Blastomyces). Chloramphenicol inhibits bacterial flora.


Which of the following statments regarding pseudohyphae is incorrect?

1 Pseudohyphae are seen in yeasts

2 Are constricted at septations

3 Branching occurs at septations

4 The terminal cell is smaller than the others

5 Are not septated


Which of the following statments regarding pseudohyphae is incorrect?

5 Are not septated

Pseudohyphae are seen in yeast and resemble true hyphae except that they are

constricted at septations, branching occurs at septations, and the terminal cell is

smaller than the others. They are septated.


Trichophyton tonsurans sporulates via thick-walled round cells resistant to the

environment known as:

1 Arthroconidia

2 Blastoconidia

3 Chlamydoconidia

4 Sporangia


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5 Mycelia


Trichophyton tonsurans sporulates via thick-walled round cells resistant to the

environment known as:

3 Chlamydoconidia

Chlamydoconidia are thick-walled round cells, resistant to the environment.

Arthroconidia are formed by fragmentation of hyphae, and may appear as thick or

thin-walled rectangular cells. Blastoconidia are formed by budding. Sporangia are

spores that are produced in a sac.


Which of the following is true regarding culture of the organisms that cause Pityriasis

versicolor?

1 Difficult to grow, requires olive oil overlay

2 Grow easily on Mycosel media

3 Cannot be cultured

4 Grow easily on Dermatophyte Test Media

5 Grow easily on Sabouraud Dextrose Agar


Which of the following is true regarding culture of the organisms that cause Pityriasis

versicolor?

1 Difficult to grow, requires olive oil overlay

Pityriasis versicolor (Tinea versicolor) is caused by Malassezia furfur, M. globosa(most common cause), M. pachydermatis, M. dermatis, M. obtuse, M. restrica, M.

sympodialis, and M. sloofiae. The organisms that cause Pityriasis versicolor are

difficult to grow. The culture requires olive oil overlay.


Medlar bodies are diagnostic of infection with which organism?

1 Blastomycosis

2 Chromomycosis

3 Coccidiomycosis

4 Histoplasmosis

5 Sporotrichosis


Medlar bodies are diagnostic of infection with which organism?

2 Chromomycosis

Chromoblastomycosis, or chromomycosis, is a cutaneous mycosis caused by

dematiaceous, or pigmented, fungi. Several fungal species are associated with this

infection including Phialophora verrucosa, Fonsecaea pedrosoi, F compactum,

Exophiala (Fonsecaea, Wangiella) dermatitidis and Cladosporium carrionii. Infection

is typically trauma-induced and involves the lower extremities. Lesions appear as


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verrucous papules, nodules and plaques, with occasional elephantiasis resulting from

lymphatic blockage. Histopathologic findings include pseudoepitheliomatous

epidermal hyperplasia and a dermal infiltrate composed of epithelioid histiocytes,

multinucleated giant cells, and small clusters of inflammatory cells including plasma

cells, neutrophils, eosinophils and lymphocytes. The characteristic histopathologic

feature is the presence of dark brown, thick-walled, ovoid spheres in clusters or chainsreferred to as "copper pennies" or Medlar bodies. They are visible without the use of

special stains.


A mass of hyphae is known as a:

1 Sporangia

2 Conidia

3 Mycelium

4 Chlamydoconidia5 Pseudohyphae


A mass of hyphae is known as a:

3 Mycelium

A mass of hyphae (vegetative tube-like structures) is known as a mycelium.

Sporangia, Conidia, and Chlamydoconidia are structures formed through different

types of asexual reproduction. Pseudohyphae are seen in yeast.


All of the following parameters are used to distinguish dermatophytes except:1 Nutritional requirements

2 Colony morphology

3 Sucrose hydrolysis

4 Hair fluorescence

5 Growth temperature


All of the following parameters are used to distinguish dermatophytes except:

3 Sucrose hydrolysis

Sucrose hydrolysis is not a useful parameter to distinguish dermatophytes from one

another. Growth temperature, colony morphology, hair fluorescence and nutritional

requirements can be used to identify dermatophytes.


A slimy, mucoid colony growing on Sabouraud's agar at 37 degrees Celsius is

observed to produce urease. The organism is:

1 Candida albicans


3 Candida glabrata


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4 Candida tropicalis

5 Aspergilus flavus


A slimy, mucoid colony growing on Sabouraud's agar at 37 degrees Celsius is

observed to produce urease. The organism is:


Cryptococcus neoformans is an encapsulated yeast with a worldwide distribution.

Cryptococcosis is usually acquired by inhalation and subsequent dissemination to

various organs including the meninges and the skin can occur. Immunosuppressed

patients are particularly susceptible to infection. In approximately ten percent of

disseminated cases, cutaneous lesions may develop. These present as acneiform

papules or pustules and may progress to infiltrated plaques, nodules, or ulcers. Less

commonly, cutaneous lesions can represent primary cutaneous cryptococcosis via

direct inoculation of organisms into the skin. Diagnosis is made by direct microscopy

and India ink stains can aid visualization. The organisms are large, encapsulatedbudding yeasts. In histopathologic sections, capsules stain with alcian blue and

mucicarmine stains. In culture, C. neoformans is distinguished by production of

urease as well as the ability to pigment on Guizotia seed medium. Colonies are

described as slimy and mucoid. Serologic antigen-detection assays are also available.

Treatment of disseminated cryptococcosis includes amphotericin combined with

flucytosine.


This organism causes a resistant tinea pedis indistinguishable from dermatophytosis:

1 Aspergillus flavus


3 Curvularia sp.

4 Scopulariopsis

5 Fonsecaea sp


This organism causes a resistant tinea pedis indistinguishable from dermatophytosis:


This fungus is very difficult to treat due to its resistance to most antifungals. It issensitive to cylcoheximide so it should be cultured on media free of this antifungal.


Which of the following statements regarding candidal infection is FALSE?

1 Candida species displays true hyphae on potassium hydroxide examination

2Predisposing factors for candidal infection include diabetes mellitus,

hyperhidrosis and broad spectrum antibiotics

3 Candida albicans is the number one cause of mucocutaneous infections

4 Candidal infections typically do not spare the scrotum

5 Candida species may be associated with granuloma gluteale infantum


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Which of the following statements regarding candidal infection is FALSE?

1 Candida species displays true hyphae on potassium hydroxide examination

Candida species are part of the resident flora but they are also the most common cause

of opportunistic mycotic infection. Cutaneous clinical manifestations include thrush,perleche, paronychia, onychomycosis, intertrigo, and folliculitis. Candida albicans is

the most common organism; however, C. dubliniensis is often implicated in mucosal

disease in AIDS patients. C. parapsilosis causes chronic paronychia and C. glabrata is

fluconazole resistant. Infection is most common in the extreme of age, and the

mucosal disease is prevalent in HIV patients. Factors predisposing patients to

infection include impaired mucocutaneous barrier function, immunodeficiencies,

broad spectrum antibiotic use, malignancies, heat, humidity, friction, diabetes, and

indwelling catheters. Groin infections often involve the scrotum unlike tinea cruris

caused by dermatophytes. On KOH examination, budding yeast and pseudohyphae

(not true hyphae) are diagnostic. Predisposing factors for granuloma gluteale infantum

include occlusion, topical corticosteroids, and possibly Candida diaper dermatitis.


What organism produces round thick walled spiny macroconidia and pear shaped

microconidia?

1 Sporothrix schenckii

2 Blastomyces dermatitidis

3 Paracoccidioides brasiliensis




What organism produces round thick walled spiny macroconidia and pear shaped

microconidia?


At room temperature Histoplasma capsulatum produces round thick walled spiny

macroconidia and pear shaped microconidia.


All of the following are common causes of chromoblastomycosis EXCEPT:

1 Cladosporium carrionii

2 Rhinocladiella aquaspera


4 Pseudallescheria boydii

5 Fonsecaea pedrosi


All of the following are common causes of chromoblastomycosis EXCEPT:


Chromoblastomycosis is a chronic fungal infection of the skin and the subcutaneous


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tissue caused by traumatic inoculation of a specific group of dematiaceous

(pigmented) fungi. Fonsecaea pedrosoi is the most common causative organism, but

Fonecaea compacta, Rhinocladiella aquaspersa, Phialophora verrucosa, Exophilia

jeanselmei and Cladosporium carrionii are pathogenic as well. It is found most

commonly in agricultural workers in the tropics and subtropics, and it is notoriously

resistant to therapy. It presents as verrucous papules and plaques that may coalesce.Histopathological findings include brown, thick-walled cells known described as

copper pennies.Early in its course, limited disease may respond to surgicalexcision, electrodessication or cryosurgery. More extensive lesions may require

systemic antifungal agents including itraconazole or terbinafine, which are the

treatments of choice.


All of the following statements about paracoccidioidomycosis are true EXCEPT?

1 It is most common in male agricultural workers

2 It has a characteristicmariners wheelappearance on histopathology3 Disease is almost always confined to the skin

4 It is endemic to Brazil

5 It may cause mucocutaneous lesions


All of the following statements about paracoccidioidomycosis are true EXCEPT?

3 Disease is almost always confined to the skin

Paracoccidioidomycosis is caused by Paracoccidioidomycosis brasiliensis, and is

endemic to Central and South America, especially Brazil, Argentina, Venezuela,Ecuador and Columbia. Male agricultural workers are at greatest risk. Infection is

most commonly caused by direct inoculation which leads to pulmonary disease. Lung

disease may be followed by dissemination to mucocutaneous surfaces, gastrointestinal

tract, spleen, adrenal glands, and lymph nodes. Cutaneous lesions are verrucous

and/or ulcerative, and usually found on the face and in the nasal and oral mucosa.

Primary mucocutaneous disease exists as well and is caused by direct inoculation.

Biopsy specimens display multiple narrow-based budding yeast cells, described as a

mariners wheel.The treatment of choice is itraconazole.


A 45 year-old agricultural worker from Brazil presented with ulcers of the buccal

mucosa and tongue. Cervical lymph nodes were tender and enlarged. The biopsywould most likely reveal:

1Yeast cells in chains and a large thick walled round central yeast cell

surrounded by several thinly attached budding smaller yeast cells

2 Yeast cells with large capsules

3 Small budding yeast cells

4 Yeast cells with pseudohyphae

5 Copper pennies



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A 45 year-old agricultural worker from Brazil presented with ulcers of the buccal

mucosa and tongue. Cervical lymph nodes were tender and enlarged. The biopsy

would most likely reveal:

1Yeast cells in chains and a large thick walled round central yeast cell

surrounded by several thinly attached budding smaller yeast cells

Yeast cells in chains and a large thick walled round central yeast cell surrounded by

several thinly attached budding smaller yeast cells p.18. This biopsy is describing

Paracoccidioides brasiliensis, an organism endemic in Brazil. Its yeast form seen in

tissue produces a Mariners wheel-like configuration. Generally this organism is

inhaled and disseminates causing mucocutaneous lesions with lymphadenopathy.


Choose the correct statement regarding Coccidioidomycosis:

1 The most common form of primary inoculation is cutaneous

2 Dissemination may involve the bones, joints, viscera, brain and skin

3 Causative organism, C. immitits, is a thick-walled spherule with apolysaccharide capsule demonstrated with Alcain blue

4 Erythema nodosum is a poor prognotic sign

5 Outbreaks occur in the Mississippi and Ohio River Valley


Choose the correct statement regarding Coccidioidomycosis:

2 Dissemination may involve the bones, joints, viscera, brain and skin

Coccidioidomycosis: Primary inoculation is pulmonary. Erythema nodosum is a

favorable prognostic sighn. Dissemination from the localized pulomary lesions may

occur in less than 1% of infections. Target ogans of dissemination include the bones,

joints, viscera, brain, meinnges, and skin. The causative organisms is Coccidioides

immitis, is a nonbudding, thick-walled spherule, with a polysaccharide capsule

demonstrated with Gridley or Gomori methanamine silver stain. It is endemic in

northern Mexico, Venezuela, and in southwest US, especially California


Which one of the following agents accounts for the depigmentation seen in pityriasis

versicolor?

1 Thymidine kinase

2 Ketoconazole

3 Acetone

4 Dicarbocyclic acid

5 Postinflammatory effect


Which one of the following agents accounts for the depigmentation seen in pityriasis

versicolor?

4 Dicarbocyclic acid

Pityriasis versicolor is primarily caused by the yeast M. furfur. M. furfur is adimorphic, lipophilic organism that can produce metabolites such as azaleic acid (a


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dicarboxylic acid) that can inhibit tyrosinase and injure melanocytes.


All of the following statements regarding superficial mycotic infections are true

EXCEPT:

1 Trichosporon species can cause systemic disease in immunocompromisedpatients

2 Malassezia furfur is the most common cause of tinea versicolor

3 Trichosporon beigelii causes white piedra

4 Malassezia species may be associated with neonatal cephalic pustulosis

5 Piedraia hortae causes black piedra


All of the following statements regarding superficial mycotic infections are true

EXCEPT:

2 Malassezia furfur is the most common cause of tinea versicolor

Trichosporon asahii can cause disseminated disease in immunocompromised patients,

especially those with neutropenia. Patients develop nodular and then necrotic lesions

and require systemic antifungal agents. Malassezia globosa is the most common cause

of tinea versicolor, not M. furfur. M. pachydermatis, M. dermatis, M. obtuse, M.

restrica, M. sympodialis and M. slooffiae are all thought to be medically important as

well. M.sympodialis is part of the skins normal flora. Trichosporon beigelii andPiedraia hortae are the etiological agents of white and black piedra respectively.

Several Malassezia species have been implicated in neonatal cephalic pustulosis

(neonatal acne).


The most common eumycotic organism in the US produces which color grains in its

microcolony?

1 White

2 Black

3 Red

4 Yellow

5 Green


The most common eumycotic organism in the US produces which color grains in its

microcolony?

1 White

The most common cause of fungal (eumycotic) eumycetoma in the US is

Pseudallescheria boydii. This and Acremonium produce white colonies. Black

colonies are caused by Exophilia, Madurella, and Curvalaria. Red colonies are created

by Actinomadura pelletieri. Yellow colonies are made by Streptomyces and Nocardia,

both causes of bacterial mycetoma.

Q/Q(M)-482372 Report a ProblemTrichosporon ovoides is a cause of:


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1 Black piedra

2 White piedra

3 Tinea nigra palmaris

4 Ectothrix tinea capitis

5 Endothrix tinea capitis


Trichosporon ovoides is a cause of:

2 White piedra

White piedra is cause by Trichosporon beigelii, or Trichosporon ovoides and T. inkin

(new nomenclature). It presents with tan to white soft, nonadherent small concretions

~1mm, seen on the scalp, beard, moustache, and pubic areas. The hairs may fluoresce.


A landscape worker complained of several tender nodules on the right dorsal handand forearm. The biopsy of the lesion showed asteroid bodies but no organisms. The

likely diagnosis is:

1 Nocardiosis

2 Blastomycosis

3 Sporotrichosis

4 Candidiasis

5 Coccidioidomycosis


A landscape worker complained of several tender nodules on the right dorsal hand

and forearm. The biopsy of the lesion showed asteroid bodies but no organisms. The

likely diagnosis is:

3 Sporotrichosis

Sporothrix schenckii produces tiny yeast cells 4-6 um difficult to demonstrate on

biopsy unless there is an overwhelming infection. Asteroid bodies are seen on H & E

and PAS as radiating fingers of eosinophilic material.


This organism is often considered a contaminant but has been reported to causeonychomycosis:

1 Sepedonium

2 Curvularia

3 Scopulariopsis

4 Penicillium

5 Phialophora


This organism is often considered a contaminant but has been reported to causeonychomycosis:


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3 Scopulariopsis

Causes white superficial onychomycosis.


This dermatophyte has a growth requirement for inositol and thiamine

1 Trichophyton equinum


3 Trichophyton concentricum




This dermatophyte has a growth requirement for inositol and thiamine


Trichophyton verrucosum is a zoophilic fungus that requires thiamine and sometimes

inositol for growth. T. violaceum and tonsurans only have a partial requirement for

thiamine. Trichophyton equinum requires niacin. (Horses are nice).


A solitary chancre-like lesion appeared on the arm of a florist who has a pet dog. No

organisms were seen on biopsy, however Sporothrix schenckii was cultured from the

tissue. This infection is known asfixed cutaneous sporotrichosis. It remains fixedbecause:

1 There is a resistance due to a prior exposure

2 There is a decreased resistance due to AIDS

3 The infection was acquired from the dog rather than from a plant

4 The infection occurred in the absence of tissue injury

5 This species of Sporothrix has limited infectivity


A solitary chancre-like lesion appeared on the arm of a florist who has a pet dog. No

organisms were seen on biopsy, however Sporothrix schenckii was cultured from the

tissue. This infection is known asfixed cutaneous sporotrichosis. It remains fixed

because:1 There is a resistance due to a prior exposure

There is a resistance due to a prior exposure.


Which actinomycotic organism has red grains?

1 Streptomyces somaliensis

2 Nocardia asteroides

3 Actinomadura madurae

4 Actinomadura pelletieri


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Which actinomycotic organism has red grains?

4 Actinomadura pelletieri

Mycetoma is a granulomatous infection of dermal and subcutaneous tissues usually

occurring on the foot. Draining sinuses containing grains characterize such infections.

Three types of mycetoma exist: eumycotic (true fungal), actinomycotic (filamentous

organisms) and botryomycotic (bacterial infections). Madurella and Leptosphaeria

species produce black grains. Pseudallescheria and Acremonium species, along with

dermatophytes, make white grains. Nocardia brasiliensis and N. asteroides produce

white grains, while Nocardia caviae and Actinomyces israelii tend to have yellow-

white grains. Actinomadura madurae produce pink or white grains and Actinomadura

pelleteri make red grains. Streptomyces somaliensis produce brown or yellow grains.


Which structure is found in a biopsy of Candida tropicalis, it is branching andpinching in at the points of septations:

1 Septate hyphae

2 Arthroconidia

3 Mosaic fungus

4 Pseudohyphae

5 Pectinate bodies


Which structure is found in a biopsy of Candida tropicalis, it is branching andpinching in at the points of septations:

4 Pseudohyphae

Pseudohyphae are products of yeast, which produce elongated yeast cells that do not

pinch off, branching and pinching in at the points of septations.


Which of the following stains is NOT used to stain fungal elements?

1 Mucicarmine

2 Periodic Acid Schiff

3 Fontana-Masson

4 Von Kossa

5 Gormori methenamine silver


Which of the following stains is NOT used to stain fungal elements?

4 Von Kossa

Mucicarmine stain is used to stain adenocarcinoma in addition to infectious organisms

including Cryptococcus and Rhinosporidium. The Cryptococcus capsule stains red.

Periodic Acid Schiff (PAS) is useful in identifying fungi, parasites, glycogen and the


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basement membrane. The wall of the organism stains red. Fontana-Masson stains

melanin black and therefore helps identify dematiaceous (melanin-producing) fungi.

Gormori methenamine silver stains fungi, parasites, Donovan bodies and

Rhinoscleroma black. Von Kossa stain is used to identify calcium by staining it black.


This dermatophyte is not an anthropophilic organism:







This dermatophyte is not an anthropophilic organism:3 Microsporum gypseum

M. gypseum is a geophilic organism, all others listed are anthropophilic.


A 30 year-old male living in the Chicago suburbs complained of a slowly growing

verrucous plaque with sharp borders on his left wrist. A biopsy revealed yeast cells

10-14 um. Mucicarmine was negative. A fluffy white colony grew at room

temperature having small round conidia on thin conidiophores. The diagnosis is:

1 Blastomycosis

2 Cryptococcosis3 Candidiasis

4 South American Blastomycosis

5 Histoplasmosis


A 30 year-old male living in the Chicago suburbs complained of a slowly growing

verrucous plaque with sharp borders on his left wrist. A biopsy revealed yeast cells

10-14 um. Mucicarmine was negative. A fluffy white colony grew at room

temperature having small round conidia on thin conidiophores. The diagnosis is:

1 Blastomycosis

The biopsy describes Blastomyces dermatitidis, the negative mucicarmine rules out

Cryptococcus. Chicago is an endemic area for Blastomyces. The colony morphology

also describes Blastomyces.


The diagnosis is phaeohyphomycosis, what is the organism 1. Alternaria sp. 2.

Bipolaris sp. 3. Fusarium sp. 4. Exophiala sp.

1 1,2,3

2 2,3,4

3 1,2,4


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4 1,3,4



The diagnosis is phaeohyphomycosis, what is the organism 1. Alternaria sp. 2.

Bipolaris sp. 3. Fusarium sp. 4. Exophiala sp.

3 1,2,4

All these organisms are dematiaceous, Fusarium is a hyalohyphomycete.


The outstanding characteristics of Aspergillus species on biopsy include:

1 Blastoconidia

2 Hyaline, septate dichotomously branching hyphae

3 Copper pennies

4Ribbon-like filaments that may be twisted and distorted branching at right

angles

5 Stain with Fontana-Mason stain


The outstanding characteristics of Aspergillus species on biopsy include:

2 Hyaline, septate dichotomously branching hyphae

Aspergillus is seen as wide (3 um) septate dichotomously branching (45angles)hyphae.


A patient with white nodules on the hair shaft has a KOH which shows hyphae and

arthroconidia. The etiology is:

1 Corynebacterium minutissimum

2 Exophiala wernickii

3 Piedraia hortae

4 Trichosporon beigelii

5 Corynebacterium tenuis

Q/Q(M)-477143 Report a ProblemA patient with white nodules on the hair shaft has a KOH which shows hyphae and

arthroconidia. The etiology is:


White piedra is an infection of the hair shaft caused by Trichosporon beigelii. Unlike

black piedra which is firmly adherent to the shaft, white piedra presents as light

brown nodules composed of hyphae and arthroconidia, which move easily along the

hair shaft. The most common sites of infection occur on the mustache, beard and

pubic area.

Q/Q(M)-477143 Report a ProblemOf the following Candida species, which is

likely to cause disseminated Candidiasis with cutaneous lesions?


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1 Candida albicans

2 C. parapsilosis

3 C. tropicalis

4 C. krusei

5 C. neoformans


Of the following Candida species, which is likely to cause disseminated Candidiasis

with cutaneous lesions?

3 C. tropicalis

C. albicans is responsible for approximately 50% of all Candidemia, but C. tropicalis

is seen with increasing frequency among patients with dissemination and cutaneous

manifestations.


A 6 year-old Hispanic girl came into the clinic with a history of alopecia and scaly

scalp for 3 weeks. The Wood's lamp examination was negative and her cervical

lymph nodes were not enlarged. It was noted that the hairs were broken off at the

surface of the scalp. The most likely organism to be isolated would be:

1 M. audouinii

2 M. canis

3 M. gypseum

4 T. tonsurans5 T. rubrum


A 6 year-old Hispanic girl came into the clinic with a history of alopecia and scaly

scalp for 3 weeks. The Wood's lamp examination was negative and her cervical

lymph nodes were not enlarged. It was noted that the hairs were broken off at the

surface of the scalp. The most likely organism to be isolated would be:

4 T. tonsurans

T. tonsurans causes the endothrix infection "Black Dot Ringworm". All other choices

cause Grey Patch Ringworm.Q/Q(M)-474013 Report a Problem

Which of the following statements about dimorphic fungi is INCORRECT?

1 Are in the mould form in the environment

2 Are in yeast/spherule form in tissue

3 Are in mould form at 25 degrees C

4 Are in yeast/spherule form at 37 degrees C

5 Are in mould form in tissue

Q/Q(M)-478213 Report a ProblemWhich of the following statements about dimorphic fungi is INCORRECT?


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5 Are in mould form in tissue

Yeasts and moulds are not mutually exclusive. Dimorphism can occur - a dimorphic

fungus will be in a mould form in the environment at 25 degrees and in a

yeast/spherule form at 37 degrees C.

Q/Q(M)-478213 Report a ProblemAlthough this organism is not a fungus, it stains with PAS and GMS and produces

spherules in tissue. This organism can be identified as:

1 Rhinosporidium seeberi


3 Penicillium marneffei

4 Prototheca wickerhami

5 Leishmania mexicana

Q/Q(M)-474065 Report a ProblemAlthough this organism is not a fungus, it stains with PAS and GMS and produces

spherules in tissue. This organism can be identified as:

4 Prototheca wickerhami

This achloic algae produces spherules or sporangia 8-20um in tissue. The mature form

is called a morula.


Which of the following DOES NOT typically cause white superficial onychomycosis?

1 Aspergillus species

2 Fusarium species


4 Scopulariopsis species



Which of the following DOES NOT typically cause white superficial onychomycosis?


In white superficial onychomycosis, the organism only invades the superficial nail

plate, and it clinically appears as chalky white patches on the nails. The most common

organism is T. mentagrophytes, but Aspergillus, Cephalosporium, Fusarium,

Acreconium and Scopulariopsis are implicated as well.


A 56-year-old male with HIV presents with multiple umbilicated brown papules onthe face. Which of the following is the least likely cause of his lesions?

1 Cryptococcus

2 Histoplasmosis

3 Coccidiomycosis

4 Penicilliosis


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5 Blastomycosis


A 56-year-old male with HIV presents with multiple umbilicated brown papules on

the face. Which of the following is the least likely cause of his lesions?

5 Blastomycosis

This patient has molluscum-like lesions on the face in the setting of

immunosuppression. The differential for such papules includes cryptococcus,

histoplasmosis, coccidiomycosis, and penicilliosis. Blastomycosis can cause

sporotrichoid lesions, warty vegetations, papillomatous proliferations, and

osteomyelitis; it usually does not produce molluscum-type papules.


A 12 year old boy has a pruritic bullous eruption on his feet. A KOH is positive and a

fungal culture shows microconidia in grape-like clusters. The etiology is:


2 Microsporum canus





A 12 year old boy has a pruritic bullous eruption on his feet. A KOH is positive and a

fungal culture shows microconidia in grape-like clusters. The etiology is:

3 Trichophyton mentagrophytesTrichophyton mentagrophytes is the dermatophyte primarily responsible for bullous

tinea pedis. It typically has septate, spiral hypahe with cigar or grape like thin-walled

microconidia.


A 49-year-old man has painless subcutaneous nodules on his feet with sinus tracts and

abscesses. Pathology shows "grain" in sinus tract drainage. A diagnosis of eumycotic

mycetoma is made. What is the most common cause in the United States?

1 Acremonium

2 Curvalaria

3 Exophilia jeanselmei


5 Nocardia


A 49-year-old man has painless subcutaneous nodules on his feet with sinus tracts and

abscesses. Pathology shows "grain" in sinus tract drainage. A diagnosis of eumycotic

mycetoma is made. What is the most common cause in the United States?


Eumycotic mycetoma is fungal and can be caused by Pseudallescheria boydii (most


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common in US), Madurella, Acremonium, curvalaria, and Exophilia jeanselmei.

Actinomycotic mycetoma is bacterial and maybe caused by Nocardia asteroids or

brasiliensis, Streptomyces, and Actinomyces.


Which of the following is the most useful morphologic feature in identifying the

mycelial phase of Histoplasma capsulatum?

1 Arthroconidia in every other cell

2 Encapsulated spores 2-5 um

3 Tuberculate macroconidia 8-14 um

4 Small oval conidia on long thin conidiophores

5 Microconidia laterally along the hyphae strand


Which of the following is the most useful morphologic feature in identifying themycelial phase of Histoplasma capsulatum?

3 Tuberculate macroconidia 8-14 um

On artificial media the mould form of Histoplasmosis produces hyphae with tear drop

microconidia and round thick wall tuberculate macroconidia.


Which of the following statements regarding lobomycosis is FALSE?

1 Itraconazole is the treatment of choice

2 It resembles achain of coinson histopathology

3 It is also known askeloidal blastomycosis

4 Lacazia (formerly Loboa) loboi is the number one cause

5 The infection also occurs in dolphins


Which of the following statements regarding lobomycosis is FALSE?

1 Itraconazole is the treatment of choice

Lobomycosis, also know as keloidal blastomycosis is caused by Lacazia loboi

(formerly Loboa loboi). It is endemic to Brazil and the Caribbean and is associated

with dolphins. Clinically, the disease presents with painless keloidal papules andplaques, ulcerative lesions and/or verrucous lesions. Biopsy specimens display

multiple budding thick-walled cells attached with a bridge, often referred to as a

chain of coins.Surgical treatment is necessary as antifungal medications areineffective.


Which of the following organisms would you expect to recover from a fluorescent

tinea capitis?

1 T. tonsurans

2 M. gypseum

3 M. canis and M. gypseum


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4 T. violaceum

5 T. rubrum


Which of the following organisms would you expect to recover from a fluorescent

tinea capitis?

3 M. canis and M. gypseum

M. gypseum may occasionally produce a dull fluorescence - all other organisms are

nonfluorescent.


Which of the following most accurately describe conidia?

1 Cells produced on the end or sides of hypha or conidiophore

2 Spores that are produced in a sac

3 Thick-walled round cell

4 Formed by budding

5 Formed by fragmentation of hyphae


Which of the following most accurately describe conidia?

1 Cells produced on the end or sides of hypha or conidiophore

Conidia are cells produced on the end or sides of hypha or conidiophore, the size and

shape arrangement are generally characteristic of the organism. The remaining

descriptions are of specific types of conidia. Spores produced in a sac are sporangia,

thick-walled round cells that are resistant to the environment are chlamydoconidia,

blastoconidia are formed by budding and arthroconidia are formed by fragmentation

of hyphae.


The etiologic agent responsible for White Piedra is:

1 Candida albicans

2 Pityrosporum obiculare

3 Corynebacterium tenuis

4 Piedra hortai

5 Trichosporon ovoides


The etiologic agent responsible for White Piedra is:


Formerly known as T. beigelii.


What is the most frequently reported cause of primary cutaneous aspergillosis?

1 Aspergillus flavus2 Aspergillus fumigatus


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3 Aspergillus niger

4 Aspergillus solani

5 Aspergillus marneffei

Q/Q(M)-477452 Report a ProblemWhat is the most frequently reported cause of primary cutaneous aspergillosis?

1 Aspergillus flavus

Primary cutaneous aspergillosis is a rare disease reported mostly frequently in

children with hematologic malignancies who developed skin lesions at the site of IV

canulas.


Penicillium marneffei is an infection endemic to which part of the world?

1 Mexico

2 South America

3 Africa

4 Southeast Asia

5 The Caribbean


Penicillium marneffei is an infection endemic to which part of the world?

4 Southeast Asia

Penicillosis is a recently recognized disease caused by infection with Penicillium

marneffei, a dimorphous fungus that is contracted through inhalation. Cases havebeen described in Vietnam, China, and Thailand as well as imported cases in the U.S.

in veterans returning from Vietnam. Bamboo rats in these areas have been shown to

be infected with P. marneffei and may represent a reservoir. Although penicillosis has

a tendency to occur in immunocompromised hosts opportunistically, it has also been

described in normal hosts. Clinical presentation is typically with pulmonary or

disseminated disease which can affect the skin, gastrointestinal tract, spleen, lymph

nodes, skin, and bone marrow. Cutaneous features include multiple umbilicated

papules which can enlarge and ulcerate occurring commonly on the face and trunk.

Diagnosis is by culture or histopathology. Treatment is with itraconazole. Severe

cases may require amphotericin B.


A creamy white colony might be any of these organisms except:

1 Candida albicans

2 Prototheca wickerhamii

3 Curvularia

4 Sporothrix schenckii at 37C


Q/Q(M)-474492 Report a ProblemA creamy white colony might be any of these organisms except:


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3 Curvularia

Is a dematiaceous organism and is the only organism listed that does not produce

creamy white colonies.


Which of the following statements regarding histoplasmosis is TRUE?

1 Terbinafine is the treatment of choice

2 Histoplasma capsulatum is a yeast at 25C

3 The organisms are intracellular on histological examination

4 The disease is most common in the San Joaquin Valley

5 The disease is primarily a mucocutaneous infection


Which of the following statements regarding histoplasmosis is TRUE?

3 The organisms are intracellular on histological examination

Histoplasmosis is primarily a pulmonary infection that can disseminate to other

organs. It is endemic to the Ohio, Missouri and Mississippi River Valleys where the

bird and bat droppings in the soil contain the fungus. Primary cutaneous disease is

extremely rare. At 25C it displays septate hyphae and at 37C H. capsulatum is ayeast. Itraconazole is the treatment of choice. On histopathological examination,

intracellular organisms that display a halo are seen. The halo is not the result of a

capsule but rather shrinkage artifact.


Which of the following methods of direct microscopic examination is chitin specific?1 Chlorazol black E

2 Calcofluor white

3 Gomori Methenamine Silver

4 Fontana-Masson

5 KOH


Which of the following methods of direct microscopic examination is chitin specific?

1 Chlorazol black E

Chlorazol black E is chitin specific. Calcofluor white is glucan specific. Gomori

Methenamine Silver (GMS) and Fontana-Masson are histology stains. KOH is a

rapid, easy, reliable method for diagnosing fungal infections, but is not chitin-specific.


Which pathogen is not inhibited by cycloheximide?

1 Cryptococcus

2 Candida albicans

3 Prototheca

4 Scopuloniopsos brevicaulis


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5 Scytalidium species


Which pathogen is not inhibited by cycloheximide?

2 Candida albicans

Cycloheximide is used is fungal culture media to reduce contaminants.


Which dermatophyte is most commonly responsible for tinea corporis gladiotorum?

1 T. mentag

2 T. tonsurans

3 T. schonlenleinii

4 T. rubrum

5 E. floccosum


Which dermatophyte is most commonly responsible for tinea corporis gladiotorum?

2 T. tonsurans

Tinea corporis gladiotorum is caused by Trychophyton tonsurans. Clinically, it

appears as well-defined, scaly plaques usually located on the arms, neck, and head.


Which of the following dermatophytes causes endothrix tinea capitis?




4 Microsporum canis

5 Microsporum ferrugineum


Which of the following dermatophytes causes endothrix tinea capitis?


Organisms that cause an ectothrix pattern of tinea capitis include M. canis, M.

audouinii, M. ferruginosum, M. distortium, M. gypseum and occasionally T. rubrum.T. tonsurans, T. violaceum, T. soudanense, T. gourvilli, T. yaoundei, and occasionally

T. rubrum cause an endothrix pattern. T. schoenleinii causes favus in which hyphae

and air spaces are seen in the hair shaft. A bluish-white fluorescence pattern is seen

with Woods lamp. Clinically, patients have thick, yellow, cup-shaped crusts(scutula); scarring and secondary infection may result. M. canis, M. audouinii, M.

ferruginosum, M. distortium display a yellow fluorescence on Woods lampexamination.


All of the following are features of mycetoma except:

1 Swelling


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2 Self-limited

3 Granules

4 Fascia and bone involvement

5 Draining sinusesQ/Q(M)-477230 Report a Problem

All of the following are features of mycetoma except:

2 Self-limited

Mycetomas may be subdivided into eumycetoma and actinomycetoma . Mycetomas

generally begin as subcutaneous swellings occurring on the feet. Later, sinuses,

granules, and nodules may be seen. The skin and subcutaneous tissue may also

become involved. Treatment is difficult in later stages.


Septate true hyphae are characterized by:1 Transverse cross walls forming within the hyphae

2 Discrete unicellular bodies

3 Constrictions at septations

4 Branching occuring at septations

5 A terminal cell that is smaller than the others


Septate true hyphae are characterized by:

1 Transverse cross walls forming within the hyphae

Hyphae are vegetative tube-like structures. In septate hyphae, transverse cross walls

form within the hyphae. Pseudohyphae, seen in yeast, resemble true hyphae except

that they are constricted at septations, branching occurs at septations, and the terminal

cell is smaller than the others.


Which of the following causes tinea imbricata?







Which of the following causes tinea imbricata?


Tinea imbricata is characterized by concentric, annular, scaly rings resembling

erythema annulare centrifugum. The causative agent is T. concentricum, which is

endemic to the South Pacific, South and Central America and Asia. The infection isusually chronic.


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This 16 year-old patient was recently diagnosed with HIV, the diagnosis is:

1 Distal Onychomycosis

2 Proximal Subungual Onychomycosis

3 Proximal White Subungual Onychomycosis

4 White Superficial Onychomycosis

5 Paronychia with Candida Onychomycosis


This 16 year-old patient was recently diagnosed with HIV, the diagnosis is:

3 Proximal White Subungual Onychomycosis

Proximal White Subungual onychomycosis is an AIDS marker, nails have a

characteristic white opaque appearance beginning in the region of the lunula and

extending distally under the nail plate.


Yeast:

1 Are filamentous fungi

2 Are characterized by tubular branching cells

3 Form fuzzy colonies

4 Form smooth colonies

5 Are unicellular oval to round cells that reproduce by budding or fission


Yeast:

5 Are unicellular oval to round cells that reproduce by budding or fission

All of the listed features are those of molds. Yeast are unicellular, oval to round cells

that reproduce by budding or fission. They form moist colonies, not smooth or fuzzy

colonies.


Which one of the following is not caused by a Candida infection?

1 Angular cheilitis

2 Balanitis

3 Median rhomboid glossitis

4 Leukoplakia

5 Mycetoma


Which one of the following is not caused by a Candida infection?

5 Mycetoma

Candidal infections may clinically present as thrush/leukoplakia, perleche/angularcheilitis, vulvovaginitis, balanitis, paronychia, onychomcosis, intertrigo, and


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folliculititis. Median rhomboid glossitis is now also associated with candidal

infections. Mycetomas are caused by true fungi (eumycetoma) or filamentous bacteria

(actinmycetoma).


Which of the following usually does not fluoresce bright green upon Woods lamp

examination?

1 M. audouinii

2 M. canis

3 T. violaceum

4 T. schoenleinii

5 M. distortum


Which of the following usually does not fluoresce bright green upon Woods lampexamination?

3 T. violaceum

Fluorescent-positive infections are caused by:"Dogs And Cats Fight Some Gypsies"

M. Distortum M. audouinii M canis M. ferrugineum T. schoenleinii M. gypsium

(occasionally)


Erythematous to violaceous papules that may progress to nodular and necrotizing skin

lesions in neutropenic patients may be caused by which of the following organisms?

1 Trichosporon asahii



4 Trichosporon inkin



Erythematous to violaceous papules that may progress to nodular and necrotizing skin

lesions in neutropenic patients may be caused by which of the following organisms?

1 Trichosporon asahii

Trichosporon asahii can cause trichosporanosis, which presents with disseminated

disease in neutropenic patients. Patients may present with erythematous to violaceous

papules that may progress to nodular and necrotizing skin lesions. Trichosporon

beigelii (new nomenclature: Trichosporon ovoides and Trichosporon inkin) causes

white piedra and other superficial infections.


A child presents with several yellowish, cup-shaped crusts on the scalp, some with

single hairs piercing through the center. KOH prep reveals arthroconidia and airspaces

within the hair shaft. A likely cause is:

1 M. gypseum


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2 M. canis

3 T. tonsurans

4 T. verrucosum

5 T. mentagrophytesQ/Q(M)-478133 Report a Problem

A child presents with several yellowish, cup-shaped crusts on the scalp, some with

single hairs piercing through the center. KOH prep reveals arthroconidia and airspaces

within the hair shaft. A likely cause is:

1 M. gypseum

This child is presenting with the characteristic scutula of favus. Favus is most often

caused by T. schoenleinii, T. violaceum, and M. gypseum.


Which of the following statements about arthroconidia is correct?1 Arthroconidia are formed by budding

2 Arthroconidia are formed by fragmentation of hyphae

3 Arthroconidia are thick-walled round cells

4 Arthroconidia are spores that are produced in a sac

5 Arthroconidia are yeast forms of dimorphic fungi


Which of the following statements about arthroconidia is correct?

2 Arthroconidia are formed by fragmentation of hyphae

Arthroconidia are formed by fragmentation of hyphae and may appear as thick or thin

walled rectangular cells. An example would be the mould form of Coccidioides

immitis. The remaining options are incorrect.


A patient has a positive Wood's light exam that is caused by pteridine. What is the

causative condition?


2 Corynebacterium


4 Pseudomonas



A patient has a positive Wood's light exam that is caused by pteridine. What is the

causative condition?


Wood's light positive dermatophytes (M. canis, M. audouinii, M. distortum, M.

ferrugineum, M gypseum, and T. schoenleinii) fluoresce secondary to pteridine.Corynebacterium can fluoresce as well due to coproporphyrin III. Pseudomonas


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fluoresces from production of pycyanin. The other organisms do not react with a

Wood's light.


Which of the following is a fluorescent ectothrix dermatophyte?

1 Trichophyton rubrum2 Trichophyton mentagrophytes



5 Microsporum nanum


Which of the following is a fluorescent ectothrix dermatophyte?


Fluorescent ectothrix dermatophytes include M. canis, M. audouinii, M. distortum, M.

ferrugineum, and sometimes M. gypseum and T. schoenleinii ("Cats And Dogs Fight

and Growl Sometimes.") Nonfluorescent ectothrix dermatophytes include T.

mentagrophytes, T. rubrum, T. verrucosum, T. megninii, and M. nanum. Endothrix

dermatophytes include T. rubrum, T. gourvilli, T. yaounde, T. tonsurans, T.

schoenleinii, T. soudanense, and T. violaceum.


Which of the following stains is specific for chitin?

1 KOH

2 KOH with DMSO3 Swartz Lamkins

4 Chlorazol Black E

5 Calcofluor White


Which of the following stains is specific for chitin?

4 Chlorazol Black E

Chlorazol Black E is a chitin specific stain. The remaining options are useful in direct

microscopic examination for fungal elements, but are not chitin specific.Q/Q(M)-478220 Report a Problem

Two weeks after a bicycle accident a 25-year-old female diabetic patient complained

of a swollen tender right cheek The PAS biopsy demonstrated ring forms and

distorted wide hyphae with few septations and right angle branching. The diagnosis

is:

1 Aspergillosis

2 Actinomycosis

3 Mucormycosis

4 Dermatophytosis


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5 Fusariosis


Two weeks after a bicycle accident a 25-year-old female diabetic patient complained

of a swollen tender right cheek The PAS biopsy demonstrated ring forms and

distorted wide hyphae with few septations and right angle branching. The diagnosisis:

3 Mucormycosis

Having diabetes is a risk factor for Mucormycosis, ring forms in the biopsy are the x-

section of the wide sparsely septate hyphae.


Cryptococcus neoformans resides in:

1 The Mississippi Valley region

2 Chicken roosts

3 Pigeon droppings

4 Sandy soil

5 None of these answers are correct


Cryptococcus neoformans resides in:

3 Pigeon droppings

This organism is ubiquitous and is abundant in soil enriched with pigeon droppings.


A fungal culture demonstrates a suedelike cream-colored colony of teardrop and

balloon-shaped microconidia which produce a red-brown pigment. Which of the

following is true of this organism?

1 Causes ectothrix infection

2 Requires partial thiamine for growth

3 Does not have arthroconidia

4 Causes fluorescent hair infection

5 Is not a cause of tinea unguim


A fungal culture demonstrates a suedelike cream-colored colony of teardrop and

balloon-shaped microconidia which produce a red-brown pigment. Which of the

following is true of this organism?

2 Requires partial thiamine for growth

Trichophyton tonsurans is an anthropophilic dermatophyte that causes non-fluorescent

endothrix hair invasion. It can cause black dot tinea capitis, tinea corporis, tinea pedis,

and tinea unguium. An important identifying feature of T. tonsurans is its red-brown

pigment that diffuses into the medium. Also, abundant tear-drop or club shaped

microconidia can be found. It grows best in the presence of thiamine.



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This agent causes a superficial, asymptomatic infection usually on the palms of the

hands. The lesions are flat, nonscaly and appear as irregularly shaped brown macules:

1 Piedra hortae

2 Cladosporium carrionii

3 Aureobasidium pullulans

4 Phaeoannellomyces werneckii

5 Exophiala jeanselmei


This agent causes a superficial, asymptomatic infection usually on the palms of the

hands. The lesions are flat, nonscaly and appear as irregularly shaped brown macules:

4 Phaeoannellomyces werneckii

These lesions often have a deeper pigment at the advancing border. The other

organisms are dematiaceous but are not the etiologic agent of tinea nigra.Q/Q(M)-474503 Report a Problem

Which of the following is true regarding Dermatophyte Test Media (DTM)?

1 DTM contains chlortetracycline and minocycline

2 Alizarin red is the indicator present in DTM

3 Non-dermatophytes cause the media to turn yellow due to acid byproducts

4 DTM is useful for culturing dermatophytes from skin and nails, but not hair.

5Dermatophytes utilize glucose as a carbon source, producing alkaline by-

products.Q/Q(M)-478111 Report a Problem

Which of the following is true regarding Dermatophyte Test Media (DTM)?

3 Non-dermatophytes cause the media to turn yellow due to acid byproducts

Dermatophyte Test Media (DTM) contains peptones, dextrose, gentamicin,

chlortetracycline, cycloheximide, and phenol red. Dermatophytes utilize protein as a

carbon source producing alkaline byproducts causing the media to turn from amber to

red. Nondermatophytes cause the media to turn yellow due to acid byproducts.


A whitish, heaped and convoluted colony with growth submerged into the agar and a

colorless reverse was isolated from the scalp of a 35-year-old male. The organism did

not produce any conidia. The diagnosis most likely is:

1 Microsporum canis







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A whitish, heaped and convoluted colony with growth submerged into the agar and a

colorless reverse was isolated from the scalp of a 35-year-old male. The organism did

not produce any conidia. The diagnosis most likely is:


Produces a white cerebriform colony lacking any conidia. M. ferrugineum produces arust colored colony with bamboo-like hyphae without conidia. The other organisms

produce micro and macroconidia.


A 37 year old woman from New Mexico, now 30 weeks pregnant, presents with flu-

like symptoms. Chest x-ray revealed diffuse miliary infiltrates, with blood cultures

growing Coccidioidis immitis. What is the treatment of choice?

1 Amphotericin B

2 Terbinafine

3 Itraconazole4 Griseofulvin

5 No therapy


A 37 year old woman from New Mexico, now 30 weeks pregnant, presents with flu-

like symptoms. Chest x-ray revealed diffuse miliary infiltrates, with blood cultures

growing Coccidioidis immitis. What is the treatment of choice?

1 Amphotericin B

There is an increased risk of dissemination of Coccidiomycosis in pregnant women,

especially during the third trimester and the post-partum period. In a review by Crumet al, maternal demise correlated with disease diagnosed later in pregnancy, with only

45% of patients diagnosed in the third trimester surviving (Am J Medicine

2006;119(11):Pages 993.e11-993.e17). Given that azoles have been shown to cause

teratogenicity, amphotericin B is recommended as the therapy in pregnant women.


Which of the following is NOT used for histologic examination for fungal infection?

1 Chlorazol Black-E

2 Gormori Methanamine Silver

3 Periodic Acid Schiff

4 Fontana-Masson

5 Mayer's mucicarmine


Which of the following is NOT used for histologic examination for fungal infection?

1 Chlorazol Black-E

Chlorazol Black-E is a stain specific for chitin and is used in direct examination, not

histologic preparations. The remaining options are histology sta

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