Deck 22: The Fungi of Medical Importance

Question 1

All of the following are dimorphic, true fungal pathogens except

A)Candida.
B)Histoplasma.
C)Blastomyces.
D)Coccidioides.
E)Paracoccidioides.

Answer 1

A

Question 2

Mycetoma is

A)a subcutaneous infection that looks like a tumor.
B)also called athlete's foot.
C)caused by dermatophytes.
D)only seen in the Midwest.
E)All of these choices are correct.

Answer 2

A

Question 3

Chromoblastomycosis

A)is caused by saprobes with dark-pigmented mycelia and spores.
B)is caused by dimorphic fungi.
C)is a systemic infection.
D)is a serious respiratory tract infection.
E)has a peak incidence in Alaska.

Answer 3

A

Question 4

The routes of entry for most fungi into the body are

A)urinary and reproductive.
B)digestive and respiratory.
C)blood and wounds.
D)respiratory and cutaneous.

Question 5

Amphotericin B, nystatin, and the imidazoles are all

A)mycotoxins.
B)fungal enzymes.
C)antifungal drugs.
D)culture media supplements for fungi.

Question 6

Dermatophytoses are

A)fungal infections of the skin, hair, and nails.
B)also called ringworm.
C)also called tineas.
D)often time-consuming to eradicate completely.
E)All of these choices are correct.

Question 7

The highest incidence of histoplasmosis in the United States occurs in the

A)Southeast.
B)Southwest.
C)East and Midwest.
D)Northeast.
E)Rocky Mountains.

Question 8

Microsporum, Trichophyton, and Epidermophyton

A)produce tissue-damaging mycotoxins.
B)all cause athlete's foot.
C)have reservoirs that include humans, animals, and soils.
D)frequently cause septicemia.
E)are dimorphic fungi.

Question 9

All of the following pertain to Candida albicans, except

A)it is an opportunistic yeast.
B)small numbers found in the mouth, intestines, genitalia, and skin.
C)it has a large capsule.
D)infections often arise from an endogenous source.
E)persistent moist skin influences infection.

Question 10

Characteristics of Histoplasma capsulatum include

A)it grows in moist soil, rich in nitrogen from bird and bat guano.
B)it is a yeast with a capsule.
C)it is a dermatophyte.
D)it grows in dry, arid soil.

Question 11

Which is mismatched?

A)Tinea capitis - ringworm of the beard
B)Tinea pedis - ringworm of the foot
C)Tinea cruis - ringworm of the groin
D)Tinea corporis - ringworm of the body
E)Tinea unguium - ringworm of the nails

Question 12

Which is incorrect about tinea versicolor?

A)It is a superficial mycosis.
B)It is often transmitted by fomites.
C)It is caused by the yeast Malassezia furfur.
D)It causes disruption of skin pigmentation resulting in a mottled appearance.
E)It occasionally causes systemic infections in compromised patients.

Question 13

Paracoccidioides is

A)a superficial mycosis.
B)endemic to regions of Central and South America.
C)only seen in immunocompromised patients.
D)also known as valley fever.
E)All of these choices are correct.

Question 14

Which is incorrect about Sporothrix schenckii?

A)It is dimorphic.
B)It lives in the soil.
C)It is often transmitted by soil-contaminated thorns.
D)It causes a superficial cutaneous infection.
E)It causes nodules along regional lymphatic channels.

Question 15

Transmission of tineas include

A)human to human.
B)animal to human.
C)soil to human.
D)fomites to human.
E)All of these choices are correct.

Question 16

The ability of a fungus to grow as a yeast or a mold depending on its environmental temperature is called

A)fungal virulence.
B)parasitism.
C)dimorphism.
D)dermatophytes.
E)opportunistic fungi.

Question 17

The terms used for the four general types of fungal infection include the following, except

A)cutaneous.
B)blood-borne.
C)systemic.
D)subcutaneous.
E)superficial.

Question 18

Which is incorrect about histoplasmosis?

A)The pathogen grows inside macrophages.
B)It is transmitted by inhalation of spores.
C)Respiratory infections range from mild to severe.
D)Chronic cases have symptoms similar to tuberculosis.
E)Histoplasmosis never spreads to sites outside the respiratory tract.

Question 19

Blastomyces dermatitidis

A)causes Gilchrist's disease and Chicago's disease.
B)is transmitted by skin contact with fomites.
C)is a dermatophyte.
D)usually enters through the gastrointestinal tract
E)All of these choices are correct.

Question 20

All of the following pertain to coccidioidomycosis, except

A)the pathogen grows best in soil with bird and bat guano.
B)fungomas occur in the lungs of those infected.
C)it is transmitted by inhalation of arthrospores.
D)it often has symptoms of fever, chest pain, cough, headache, malaise.
E)it is also called valley fever.

Question 21

Serious mycoses treated with amphotericin B include all the following, except

A)zygomycosis.
B)invasive aspergillosis.
C)Pneumocystis pneumonia.
D)coccidioidomycosis.
E)histoplasmosis.

Question 22

Oral thrush is caused by

A)Cryptococcus neoformans.
B)Candida albicans.
C)Malassezia furfur.
D)Pneumocystis (carinii) jiroveci.

Question 23

Which of the following is a rare mycosis caused by a mold commonly found in soil, in dairy products, and on the human body?

A)bark stripper's disease
B)valley fever
C)sporotrichosis
D)geotrichosis
E)pneumocystis pneumonia

Question 24

Pneumocystis jirovecii

A)has protozoan and fungal characteristics.
B)lacks ergosterol in its plasma membrane.
C)is an obligate parasite.
D)causes serious infection in elderly, premature infants, and AIDS patients.
E)All of these choices are correct.

Question 25

Candidiasis includes

A)intertriginous infection of skin sites.
B)vulvovaginal infection.
C)oral cavity and esophageal infections.
D)skin and nail infections.
E)All of these choices are correct.

Question 26

The primary portal of entry for fungal infections is

A)the urinary tract.
B)through skin.
C)the respiratory tract.
D)the nervous system.
E)the digestive system.

Question 27

Which antifungal drug inhibits cell division of the fungus?

A)ketoconazole (Nizoral)
B)fluconazole
C)terbinafine (Lamisil)
D)amphotericin B
E)griseofulvin

Question 28

Sabouraud's dextrose agar is a lab medium for supporting growth of fungi.

Question 29

All of the following areas are subject to intertriginous infections, except

A)between folds of the groin.
B)under breasts.
C)in the armpit.
D)behind the knees.
E)chest.

Question 30

This organism commonly contaminates grains, corn, and peanuts and produces a potent mycotoxin called aflatoxin?

A)Pneumocystis (carinii) jiroveci
B)Fusarium species
C)Rhizopus species
D)Geotrichum candidum
E)Aspergillus flavus

Question 31

Cryptococcosis can include

A)pulmonary infection.
B)septicemia.
C)meningitis.
D)bone infection.
E)All of these choices are correct.

Question 32

Which is incorrect about chromoblastomycosis?

A)It is characterized by highly visible verrucous lesions.
B)Treatment is with pentamidine.
C)Its etiological agent are soil saprobes with dark-pigmented mycelia and spores.
D)Sclerotic cells are produced.
E)It is frequently confused with yaws, cancer, and syphilis.

Question 33

Alternative names for Blastomyces dermatitidis include

A)Gilchrist's disease.
B)valley fever.
C)rose Gardener's disease.
D)teapicker's lung.
E)farmer's lung.

Question 34

Cryptococcus neoformans has the following characteristics, except

A)it is commonly found in the human mouth, intestines, and genitalia.
B)it is an encapsulated yeast.
C)it can be found in high numbers in soil containing pigeon droppings.
D)it usually enters body by inhalation.
E)it primarily infects patients with AIDS, cancer, and diabetes.

Question 35

All of the following are fungal allergies, except

A)bark stripper's disease.
B)farmer's lung.
C)teapicker's lung.
D)thrush.
E)All of these choices are correct.

Question 36

This opportunist is the most frequent cause of life-threatening pneumonia in AIDS patients.

A)Cryptococcus neoformans
B)Candida albicans
C)Malassezia furfur
D)Pneumocystis jirovecii.

Question 37

Which of the following is incorrect about sporotrichosis?

A)It is also known as valley fever.
B)Humans and other mammals are susceptible.
C)Heat packs applied to skin lesions can resolve some infections.
D)A prick of a thorn is the classic mode of infection.
E)The sporotrichin skin test can be used to determine prior infection.

Question 38

Which of the following are likely to predispose patients to fungal infections?

A)cancer
B)AIDS
C)tuberculosis
D)malnutrition
E)All of these choices are correct.

Question 39

Aspergillosis includes all the following, except

A)there are no effective drugs to treat the infection.
B)noninvasive infections of the eyelids, sinuses, conjunctiva, and ear canals.
C)a pneumonia that disseminates to the brain.
D)most cases are due to A.fumigatus.
E)life-threatening infections in AIDS, leukemia, and transplant patients.

Question 40

Decaying vegetation, such as piles of leaves and compost matter, allows growth and transmission of

A)Cryptococcus.
B)Aspergillus.
C)Candida.
D)Dermatophytes.
E)Pneumocystis.

Question 41

Adding salt and sugar can control the growth of certain bacteria but not fungi.

Question 42

Trichophyton species infect hair, skin, and nails, whereas Microsporum species infect hair and skin but not nails.

Question 43

Fungi that exhibit thermal dimorphism grow as _____ at 30°C and as _____ at 37°C.

Question 44

Diseases caused by fungi are termed _____.

Question 45

Dermatophyte spores can survive for years on fomites.

Question 46

Skin testing with antigen is used to diagnose ringworm.

Question 47

All fungi are heterotrophic and can break their substrates down by secreting enzymes.

Question 48

Amphotericin B is an over-the-counter drug to treat athlete's foot.

Question 49

_____ are superficial mycoses that cause white masses or dark masses to develop on the hair shaft.

Question 50

Tough, warty verrucous lesions are seen in patients with tinea versicolor.

Question 51

Sporotrichosis is associated with soil high in pigeon droppings that is introduced into subcutaneous tissue.

Question 52

Patient's with madura foot develop swollen, ulcerative, tumor-like skin lesions called mycetomas.

Question 53

The typical transmission of dimorphic fungi is inhalation of _____.

Question 54

Blastomycosis begins as a respiratory infection that can spread to the skin.

Question 55

Fungi cannot be found growing in nutritionally poor and adverse conditions.

Question 56

The most common route of transmission for true pathogenic fungi is ingestion of spores.

Question 57

Thermal dimorphism is associated with opportunistic fungi and never seen in true fungal pathogens.

Question 58

Fungal spores are common allergens that cause hypersensitivities.

Question 59

Most mycoses are not communicable.

Question 60

Dermatophytes digest the protein _____, found in the skin, hair, and nails.

Question 61

A 42-year-old male construction worker in southern Arizona developed a cold-like illness, experiencing a chronic cough, chest pain, headaches, and general fatigue.When the symptoms did not abate after several weeks, he visited his physician who ordered microscopic examination and culture of his sputum specimen.Direct microscopic exam demonstrated the presence of large spherule structures full of endsospores.The specimen was cultured at both 25°C and 37°C.The plate incubated at 25°C grew tan colonies with a fluffy white center.Examination of these colonies microscopically showed branching septate hyphae.As the culture matured, the hyphae fragmented into arthrospores.What is the most likely diagnosis?

A)candidiasis
B)coccidioidomycosis
C)blastomycosis
D)histoplasmosis
E)sporotrichosis

Question 62

Rhizopus, Absidia, and Mucor are mold genera that cause the disease called _____.

Question 63

Ben, a 17-year-old wrestler, developed a lesion on his upper back.The lesion was relatively round and consisted of a pink scaly rough center and raised edge.While it wasn't painful, the itching was bothersome to the young man.His coach advised him to see his doctor about the lesion.Upon visiting his physician, a scraping of the affected area was collected and placed in a drop of KOH, then examined under the microscope, revealing slender fungal hyphae.A culture was inoculated, which grew a spreading flat fuzzy colony after 10 days of incubation at 30°C.Microscopic examination of the culture demonstrated the presence of both macroconidia and microconidia.
What is the most likely diagnosis?

A)candidiasis
B)sporotrichosis
C)tinea versicolor
D)dermatophytosis
E)cutaneous blastomycosis

Question 64

Which of the following is/are true of cryptococcal meningitis?

A)It is most often caused by Cryptococcus gattii.
B)The pathogen usually enters the body via the respiratory route.
C)It is usually a mild form of meningitis that is self-limiting.
D)It is most often seen in patients with AIDS.
E)The pathogen can be detected in CSF specimens by negative staining.

Question 65

Compare and contrast Histoplasmosis, Coccidioidomycosis, and Blastomycosis with regard to: a) causative agent, b) reservoir, c) transmission, and d) disease, including complications.

Question 66

Discuss why the use of broad-spectrum oral antimicrobics often lead to oral thrush and vulvovaginal candidiasis superinfections.

Question 67

Discuss at least 5 factors that predispose certain individuals to opportunistic fungal infections.

Question 68

During a visit to her doctor, a woman pointed out a red rash that occurred just under her breasts.The doctor collected a scraping of the affected area, suspended the scrapings in potassium hydroxide, and then examined it microscopically.Upon viewing, she detected budding yeast cells and pseudohyphae.What is the most likely diagnosis?

A)yeast infection - candidiasis
B)dermatophyte infection
C)subcutaneous mycosis
D)yeast infection - cryptococcosis

Question 69

The cell-mediated immune response appears to play a more significant role in antifungal defenses than does the antibody-mediated immune response.

Question 70

Which of the following appears to play the least significant role in antifungal defenses in humans?

A)phagocytosis
B)IgG antibodies
C)cell-mediated immunity
D)inflammatory response

Question 71

The nodular, tumor-like fungal growths seen in certain chronic lung infections are called _____.

Question 72

Which of the following provides information about the nature and potential cause of a fungal infection the most quickly?

A)culture on Sabouraud's dextrose agar
B)testing for temperature dimorphism
C)direct examination of fresh specimens (wet mounts, KOH preps, brighteners)
D)culture on selective and differential media

Question 73

Explain why Pneumocystis jirovecii has been difficult to classify, and why traditional antifungal drugs are not effective against this microbe.