Deck 22: Pathogenic Fungi

Question 1

A retiree,tired of Minnesota winters,moves to Tucson,Arizona.He hopes the warm dry climate will ease his chronic respiratory problems.He soon experiences a new kind of weather,a massive dust storm.With which of the following fungi might he become infected?

A) Blastomyces dermatitidis
B) Coccidioides immitis
C) Histoplasma capsulatum
D) Paracoccidioides brasiliensis
E) Aspergillus fumigatus

Answer 1

B

Question 2

Which of the following is NOT a major contributor to opportunistic mycoses?

A) an invasive medical procedure
B) growth of fungus in food
C) immunosuppressive therapy
D) severe malnutrition
E) chronic diseases like diabetes

Answer 2

B

Question 3

All of the true pathogen fungi discussed in this chapter are

A) members of the Ascomycota.
B) members of the Zygomycota.
C) dimorphic.
D) members of the Ascomycota and are dimorphic.
E) members of the Zygomycota and are monomorphic.

Answer 3

D

Question 4

Which of the following is an opportunistic pathogenic fungus in humans?

A) Blastomyces dermatitidis
B) Coccidioides immitis
C) Candida albicans
D) Histoplasma capsulatum
E) Paracoccidioides brasiliensis

Question 5

Ringworm is caused by

A) worms infected with fungi invading the skin.
B) dermatophytes that have invaded deep into the living tissue.
C) dermatophytes growing in the outer dead tissue layers of the skin (epidermis).
D) a hypersensitivity caused by superficial contact with dermatophytes.
E) toxins produced by dermatophytes.

Question 6

Histoplasma capsulatum

A) is an opportunistic fungus.
B) produces arthrospores.
C) produces capsules.
D) produces yeast cells with a "steering wheel" formation.
E) is an intracellular parasite.

Question 7

Which of the following types of fungal disease is primarily the result of ingestion?

A) mycosis
B) dermatophytosis
C) hypersensitivity
D) toxicosis
E) both mycosis and dermatophytosis

Question 8

Which of the following media is preferred for the culture of fungi?

A) Sabouraud dextrose agar
B) sheep blood agar
C) MacConkey agar
D) chocolate agar
E) Thayer-Martin media

Question 9

Pneumocystis jiroveci is

A) easy to grow in the laboratory.
B) actually a protozoan and not a fungus.
C) an obligate parasite that cannot survive outside the lungs.
D) a common member of the human respiratory microbiota.
E) a member of the human microbiota that is an obligate parasite.

Question 10

Which of the following fungal infections was extremely rare prior to the AIDS epidemic?

A) pulmonary cryptococcosis
B) cutaneous candidiasis
C) hypersensitivity aspergillosis
D) mycetomas
E) Pneumocystis pneumonia

Question 11

Ocular histoplasmosis is a(n)

A) type I hypersensitivity immune reaction.
B) cytotoxic immune cell reaction.
C) delayed hypersensitivity reaction.
D) autoimmune disease.
E) example of contact dermatitis.

Question 12

An avid gardener in eastern North America begins to have a fever and cough.A sample from her lungs contains yeast cells and pus.She may be infected with

A) Amanita phalloides.
B) Blastomyces dermatitidis.
C) Claviceps purpurea.
D) Mucor.
E) Paracoccidioides brasiliensis.

Question 13

What is the diagnostic structure produced by Paracoccidioides brasiliensis?

A) spiny spores visible by brightfield microscopy
B) "steering wheel" or "captain's wheel" buds visible by brightfield microscopy
C) spherules observed in tissue samples
D) yeast buds that are not dissolved by KOH
E) dimorphism when grown in the lab

Question 14

An elderly woman is experiencing fever,chest pain,difficulty breathing,and a cough that occasionally brings up mucus containing blood.She reports having visited family in rural New Mexico over the Labor Day weekend.A GMS-stained sample from her lungs shows the presence of large spherules.Which of the following is the most likely infecting agent?

A) Coccidioides immitis
B) Blastomyces dermatitidis
C) Histoplasma capsulatum
D) Paracoccidioides brasiliensis
E) Trichophyton rubrum

Question 15

Which of the following statements about Candida is FALSE?

A) It is present in the digestive tract of 40-80% of all healthy individuals.
B) It can be transmitted to adults during sexual contact.
C) It is easily treated with topical antifungals in immunocompromised patients.
D) It causes thrush.
E) It can be passed to babies during childbirth.

Question 16

Which of the following techniques reveal(s)the presence of fungal cells in tissues?

A) Gram staining
B) KOH treatment
C) Gomori methenamine silver (GMS) staining
D) Gram staining combined with KOH treatment
E) both KOH treatment and Gomori methenamine silver (GMS) staining

Question 17

The most common disease diagnosed in humans that is caused by Cryptococcus is

A) primary pulmonary cryptococcosis.
B) cryptococcal meningitis.
C) secondary pulmonary cryptococcosis.
D) cryptococcoma.
E) cutaneous cryptococcosis.

Question 18

Opportunistic fungi

A) always have two physiological and structural forms.
B) are normal microbiota for many individuals.
C) have special proteins for colonizing the body.
D) are tracked by epidemiologists.
E) have the same geographical distribution as pathogenic fungi.

Question 19

A patient has had a cough,fever,and night sweats for many weeks.Now,sores on the mucous membranes of his mouth are appearing.His history states he spent time in the jungles of Central America.He may be suffering from

A) paracoccidioidimycosis.
B) histoplasmosis.
C) blastomycosis.
D) aspergillosis.
E) coccidioidomycoses.

Question 20

Most mycoses are difficult to treat because

A) many fungi have developed resistance antifungal agents.
B) fungicides are rapidly metabolized by the liver.
C) fungal cells provide few targets for selective toxicity.
D) treatment causes major disruption of the microbiota.
E) fungicides are extremely expensive.

Question 21

The opportunistic pathogen ________ is metabolically and morphologically distinctive from other fungi and is not effectively treated with antifungal medications.

A) Candida albicans
B) Blastomyces dermatitidis
C) Aspergillus
D) Microsporum
E) Pneumocystis jirovecii

Question 22

White patches on the surface of the tongue and the oral mucosa accompanied by inflammation and swelling are signs consistent with

A) zygomycosis.
B) cryptococcosis.
C) paracoccidioidomycosis.
D) sporotrichosis.
E) candidiasis.

Question 23

Psilocybin is a

A) toxin that causes bloody diarrhea.
B) toxin that causes kidney failure.
C) toxin that acts as a hallucinogen.
D) virulence factor produced by invasive fungi.
E) growth factor produced by mycoplasmas.

Question 24

Which of the following fungal infections can be contracted through thorn pricks or wood splinters?

A) Sporothrix schenckii
B) Cladophialophora
C) Malassezia furfur
D) Gyromitra esculenta
E) Aspergillus

Question 25

Why are subcutaneous mycoses uncommon?

A) The human body is not a suitable habitat.
B) T cells are highly effective against fungus cells.
C) Injury is necessary to introduce the fungus into the tissue.
D) Only immunocompromised persons are susceptible to subcutaneous mycoses.
E) Saprobes do not grow well at body temperature.

Question 26

Which of the following can establish a subcutaneous infection known as a mycetoma?

A) Microsporum
B) Candida albicans
C) Pneumocystis jirovecii
D) Mucor
E) Pseudoallescheria

Question 27

Chronic inhalation of particular fungal allergens would lead to a(n)

A) type I hypersensitivity reaction.
B) type II hypersensitivity reaction.
C) type III hypersensitivity reaction.
D) type IV hypersensitivity reaction.
E) autoimmune disease.

Question 28

A sample of the tissue from an inflamed,pus-filled area on the lower leg is treated with KOH and stained with GMS.Under the microscope golden brown spheres are visible.With what disease are these observations consistent?

A) pityriasis
B) fungemia
C) chromoblastomycosis
D) mycetoma
E) sporotrichosis

Question 29

Which of the following is referred to as the "death cap" mushroom?

A) Amanita phalloides
B) Gyromitra esculenta
C) Psilocybe cubensis
D) Amanita muscaria
E) Cortinarius gentilis

Question 30

Which of the following fungal infections may progress to infection of the brain?

A) Coccidioides immitis
B) Cryptococcus neoformans
C) Mucor
D) both Coccidioides immitis and Cryptococcus neoformans
E) Coccidioides immitis, Cryptococcus neoformans, and Mucor

Question 31

Mycetismus is caused by

A) ingestion of food contaminated with fungus.
B) ingestion of toxic mushrooms.
C) ingestion of milk from a cow that has ingested feed contaminated with fungal toxins.
D) inhalation of fungal allergens.
E) contamination of a wound with pathogenic fungi present in the skin.

Question 32

The monomorphic fungus Rhizopus is a(n)

A) common bread mold.
B) toxic mushroom.
C) opportunistic pathogen.
D) true pathogen.
E) common bread mold and an opportunistic pathogen.

Question 33

Chronic low-level ingestion of ________ may cause liver cancer.

A) aflatoxin
B) aspergillin
C) ergotamine
D) phalloidin
E) psilocybin

Question 34

Candida albicans can establish opportunistic infections of the

A) mouth.
B) skin.
C) eye.
D) liver.
E) eyes, liver, mouth, skin, and other organs.

Question 35

Ergometrine,which is used to stimulate labor contractions,is a product of

A) Claviceps purpurea.
B) Aspergillus
C) Amanita phalloides.
D) Exophiala.
E) Piedraia hortae.

Question 36

Which of the following is known as "false morel" and causes bloody diarrhea,convulsions,and death within two days?

A) Amanita phalloides
B) Aspergillus
C) Gyromitra esculenta
D) Sporothrix schenckii
E) Mucor

Question 37

The subcutaneous infection known as ________ can produce a series of lesions spreading from the initial infection point resulting from the fungus' ability to invade the lymphatic vessels.

A) aspergillosis
B) candidiasis
C) mycetoma
D) sporotrichosis
E) zygomycosis

Question 38

Which of the following dermatophytes infects hair as well as skin?

A) Microsporum canis
B) Malassezia furfur
C) Fonsecaea pedrosoi
D) Epidermophyton floccosum
E) Trichophyton rubrum

Question 39

Which of the following contributes to the pathogenesis of Cryptococcus neoformans?

A) the ability to produce hyphae which penetrate tissues
B) the production of leukocidins
C) the production of mucinase
D) the ability to resist killing after phagocytosis
E) the production of melanin and the presence of a phagocyte-resistant capsule

Question 40

Which of the following statements about Malassezia is FALSE?

A) It is part of the microbiota of the skin.
B) It causes phaeohyphomycosis.
C) It is a basidomycete.
D) It causes pityriasis.
E) It tends to develop into a chronic infection.

Question 41

Dermatophytes,which live on the surface of the skin,are always pathogenic.

Question 42

Aspergillus causes both mycoses and mycotoxicosis.

Question 43

Which of the following produces a hallucinogenic toxin?

A) Amanita phalloides
B) Claviceps purpurea
C) Psilocybe cubensis
D) Pseudallescheria
E) Paracoccidioides brasiliensis

Question 44

Infection of the skin by Trichophyton rubrum results in raised red scaly patches of skin,a condition known as

A) dermatophytosis.
B) candidiasis.
C) mucormycosis.
D) pityriasis.
E) sporothrichosis.

Question 45

Systemic infections with fungus are difficult to treat because fungi are metabolically similar to humans,so antifungal therapies are sometimes complicated by side effects.

Question 46

Factors that contribute to difficulty in eliminating fungal infections via the body's defenses include

A) the capsules of some fungi resist phagocytosis.
B) many fungi are resistant to cell mediated immune responses.
C) many pathogenic fungi produce leukocidins.
D) both resistance to phagocytosis and cell mediated immunity.
E) many pathogenic fungi are resistant to the action of complement.

Question 47

The best strategy for preventing fungal disease is (avoidance/prophylatic treatment/vaccination).

Question 48

Histoplasma and Coccidioides produce tuberculosis-like damage to the lungs that can be seen on X-ray images.

Question 49

Fungi that cause systemic mycoses are uniformly acquired by ingesting contaminated food.

Question 50

Ringworm is a type I hypersensitivity response to fungus spores.

Question 51

A large number of antifungal agents are available for treating fungal infections.

Question 52

Vaccines to prevent fungal infection are widely available because attenuated strains are safe.

Question 53

Most fungi exist as (parasites/saprobes/autotrophs)and function as the major decomposers of organic material.

Question 54

The true pathogenic fungi responsible for systemic mycoses have (dimorphic/monomorphic/polymorphic)growth characteristics.

Question 55

Very few cases of cryptococcal infections are caused by the variant Cryptococcus neoformans neoformans.

Question 56

A solution of (GMS/KOH/DIF)is used to dissolve keratin and cellular material in skin scrapings,leaving only the fungal cells for examination.

Question 57

Infections with (dermatophytes/pathogens/opportunists)are commonly acquired by person-to-person direct contact.

Question 58

Early treatment for mushroom poisoning includes

A) antitoxin therapy.
B) antifungal therapy.
C) ingestion of activated charcoal.
D) kidney dialysis.
E) rehydration therapy.

Question 59

The seriousness of Coccidioides infection can be attributed to the formation and rupture of spherules.

Question 60

Pityriasis,characterized by patches of hyperpigmented and depigmented skin on the trunk and arms,is due to cutaneous infection with

A) Epidermophyton floccosum.
B) Cryptococcus neoformans.
C) Malassezia furfur.
D) Microsporum canis.
E) Trichophyton rubrum.

Question 61

A man has difficulty breathing,a cough,and is running a fever.He is an avid bird-watcher who recently visited a rookery where thousands of birds build their nests and raise their young.What fungal infection(s)might he have contracted? What diagnostic tests would confirm the diagnosis? What treatment might be prescribed?

Question 62

The opportunistic obligate parasite (Microsporum/Pneumocystis/Rhizopus)is considered a member of the normal microbiota.

Question 63

Exposure to (Aspergillus/Candida/Microsporum)species most commonly causes allergies.

Question 64

Blastomyces dermatitidis occurs in the (eastern/central/southwestern/western)part of North America.

Question 65

Clusters of budding yeast and branching pseudohyphae are consistent with (candidiasis/dermatophytosis/histoplasmosis).

Question 66

A fungus in the genus (Candida/Penicillium/Trichophyton)has recently been recognized as an opportunistic pathogen of AIDS patients.

Question 67

Distinguish mycotoxicosis from mycetismus.

Question 68

The cell membranes of fungi contain (cholesterol/ergosterol/fatty acid)which is a target of some antifungal treatments.

Question 69

Compare and contrast dermatophytosis and pityriasis.

Question 70

The opportunistic infection known as (aspergillosis/cryptococcosis/sporotrichosis)may develop into a series of nodular,pus-filled lesions on a limb.

Question 71

The presence of (hyphae/spores/spherules)in a sample from the lungs is diagnostic for coccidioidomycosis.

Question 72

Why are mycoses among the most difficult diseases to treat?

Question 73

More fungal diseases are recognized than were known just a decade ago.For example,in 2012,hundreds of patients developed a meningitis caused by a fungus never before known to cause disease.What contributes to these emerging diseases?

Question 74

The production of distinctively (smooth/bumpy/spiny)spores is diagnostic for Histoplasma capsulatum.

Question 75

Peanut butter was prepared using peanut on which Aspergillus had grown.Several people who ate it suffered from (mycetismus/mycetoma/mycotoxicosis).