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2. Regarding Cryptococcus neoformans, which one of the following is most
accurate?
(A) It is a dimorphic fungus, growing as a mold in the soil and a yeast in the
body.
(B) It is acquired primarily by ingestion of food contaminated with pigeon guano.
(C) Dark field microscopy is typically used to visualize the organism in spinal
fluid.
(D) Pathogenesis involves an exotoxin that acts as a superantigen recruiting
lymphocytes into the spinal fluid.
(E) Laboratory diagnosis of cryptococcal meningitis can be achieved by detecting
the capsular polysaccharide of the organism in the spinal fluid.
accurate?
(A) It is a dimorphic fungus, growing as a mold in the soil and a yeast in the
body.
(B) It is acquired primarily by ingestion of food contaminated with pigeon guano.
(C) Dark field microscopy is typically used to visualize the organism in spinal
fluid.
(D) Pathogenesis involves an exotoxin that acts as a superantigen recruiting
lymphocytes into the spinal fluid.
(E) Laboratory diagnosis of cryptococcal meningitis can be achieved by detecting
the capsular polysaccharide of the organism in the spinal fluid.
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3. Regarding Aspergillus fumigatus and aspergillosis, which one of the following is
most accurate?
(A) The natural habitat of A. fumigatus is the hair follicles of the human skin.
(B) In the clinical laboratory, cultures of A. fumigatus incubated at 37°C form
yeast colonies.
(C) The India ink stain is typically used to visualize A. fumigatus in the clinical
laboratory.
(D) A. fumigatus causes “fungus balls” in patients with lung cavities caused by
tuberculosis.
(E) The main predisposing factor to allergic bronchopulmonary aspergillosis is
neutropenia
most accurate?
(A) The natural habitat of A. fumigatus is the hair follicles of the human skin.
(B) In the clinical laboratory, cultures of A. fumigatus incubated at 37°C form
yeast colonies.
(C) The India ink stain is typically used to visualize A. fumigatus in the clinical
laboratory.
(D) A. fumigatus causes “fungus balls” in patients with lung cavities caused by
tuberculosis.
(E) The main predisposing factor to allergic bronchopulmonary aspergillosis is
neutropenia
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4. Regarding Mucor species, which one of the following is most accurate?
(A) Infection is acquired by the ingestion of food contaminated by spores of the
organism.
(B) Diabetic ketoacidosis is a major predisposing factor for invasive
mucormycosis.
(C) Mucor species have septate hyphae in contrast to Aspergillus species, which
have nonseptate hyphae.
(D) In biopsy specimens obtained from patients with invasive disease, Mucor
species appear as pseudohyphae.
(E) Skin tests using mucoroidin as the immunogen are used to determine whether
the patient has been infected with Mucor species.
(A) Infection is acquired by the ingestion of food contaminated by spores of the
organism.
(B) Diabetic ketoacidosis is a major predisposing factor for invasive
mucormycosis.
(C) Mucor species have septate hyphae in contrast to Aspergillus species, which
have nonseptate hyphae.
(D) In biopsy specimens obtained from patients with invasive disease, Mucor
species appear as pseudohyphae.
(E) Skin tests using mucoroidin as the immunogen are used to determine whether
the patient has been infected with Mucor species.
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5. Your patient is a 20-year-old woman who is human immunodeficiency virus
(HIV) antibody positive with a CD4 count of 50. She has recovered from
cryptococcal meningitis. Which one of the following is the best choice of drug to
use as long-term prophylaxis to prevent another episode of cryptococcal
meningitis?
(A) Amphotericin B
(B) Caspofungin
(C) Fluconazole
(D) Flucytosine
(E)Terbinafine
(HIV) antibody positive with a CD4 count of 50. She has recovered from
cryptococcal meningitis. Which one of the following is the best choice of drug to
use as long-term prophylaxis to prevent another episode of cryptococcal
meningitis?
(A) Amphotericin B
(B) Caspofungin
(C) Fluconazole
(D) Flucytosine
(E)Terbinafine
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6. Your patient is a 1-month-old infant with whitish lesions in the mouth that are
diagnosed as oropharyngeal candidiasis (thrush). Which one of the following is
the best choice of drug to treat this infection?
(A) Amphotericin B
(B) Caspofungin
C) Fluconazole
(D) Flucytosine
(E) Terbinafine
diagnosed as oropharyngeal candidiasis (thrush). Which one of the following is
the best choice of drug to treat this infection?
(A) Amphotericin B
(B) Caspofungin
C) Fluconazole
(D) Flucytosine
(E) Terbinafine
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7. Your patient is a 50-year-old woman with leukemia who is neutropenic from her
cancer chemotherapy. She now has disseminated aspergillosis that does not
respond to amphotericin B. Which one of the following is the best choice of drug
to treat this infection?
(A) Amphotericin B
(B) Caspofungin
(C) Fluconazole
(D) Flucytosine
(E) Terbinafine
cancer chemotherapy. She now has disseminated aspergillosis that does not
respond to amphotericin B. Which one of the following is the best choice of drug
to treat this infection?
(A) Amphotericin B
(B) Caspofungin
(C) Fluconazole
(D) Flucytosine
(E) Terbinafine
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ANSWERS
1. (B)
2. (E)
3. (D)
4. (B)
5. (C)
6. (C)
7. (B)
1. (B)
2. (E)
3. (D)
4. (B)
5. (C)
6. (C)
7. (B)
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A fungus that is found as a com-mensal in the mouth, gastrointestinai tract, and genitourinary tract but can cause opportunistic mycosis
Anonymous Quiz
3%
Trichophyton rubrum.
79%
Candida albicans.
5%
Epidermophyton floccosum.
14%
Aspergillus.
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28) Dimorphism in fungi refers to:
a-the ability of fungi to produce two types of spores
b-the ability of fungi to undergo mitosis as well as meiosis
c-the property of fungi to develop spherical and elongated forms of nuclei
d-the characteristic of certain fungi to develop male and female hyphae in one colony
E-the ability of fungi to grow in two different forms, yeast and mycelial, depending on environmental conditions
a-the ability of fungi to produce two types of spores
b-the ability of fungi to undergo mitosis as well as meiosis
c-the property of fungi to develop spherical and elongated forms of nuclei
d-the characteristic of certain fungi to develop male and female hyphae in one colony
E-the ability of fungi to grow in two different forms, yeast and mycelial, depending on environmental conditions
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All of the following diseases are caused by yeast Except one:
Anonymous Quiz
12%
Candidiasis
20%
tinea versicolor
13%
cryptococcosis
55%
fungal ball
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You have made a clinical diagnosis of meningitis in a 50-year-old immunocompromised woman. A latex agglutination test on the spinal fluid for capsular polysaccharide antigen is positive. Of the following organisms, which one is the MOST likely cause?
Anonymous Quiz
13%
Histoplasma capsulatum
69%
Cryptococcus neoformans
6%
Aspergillus fumigatus
10%
Candida albicans
2%
None of the above
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Each of the following statements concerning Cryptococcus neoformans is correct
EXCEPT:
EXCEPT:
Anonymous Quiz
13%
a. Its natural habitat is the soil, especially associated with pigeon feces.
53%
Pathogenesis is related primarily to the production of exotoxin A.
15%
Budding yeasts are found in the lesions.
11%
The initial site of infection is usually the lung.
9%
Subcutancous nodules are often seen in disseminated disease.
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Fungal cells that reproduce by budding are seen in the infected tissues of patients with:
Anonymous Quiz
69%
Candidiasis, cryptococcosis
8%
Mycetoma, candidiasis.
8%
Tinea corporis, tinea versicolor
12%
Sporotrichosis, mycetoma.
4%
Mycetoma, cryptococcosis
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Aspergillosis is recognized in tissue by the presence of:
Anonymous Quiz
4%
Budding cells
71%
Septate hyphae
9%
Metachromatic granules
5%
Pseudohyphae
11%
Non-Septate hyphac
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Each of the following statements concerning fungi is correct EXCEPT:
Anonymous Quiz
8%
Yeasts are fungi that reproduce by budding.
4%
Molds are fungi that have clongated filaments called hyphae.
8%
Thermally dimorphic fungi exist as yeasts at 37°C and as molds at 25°C.
63%
Both yeasts and molds have a cell wall made of peptidoglycan
16%
None of the above
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Dimorphic fungi are most likely to be in which of the following fungal forms obtained sample from a patient?
Anonymous Quiz
59%
Yeasts
9%
Pseudohyphac
9%
Mycelium
18%
Hyphae
5%
Endospores
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Which one of the following represents the mechanism of action of amphotericin B
Anonymous Quiz
6%
Inhibition of the activity of the enzyme, 14-a-demethylase
4%
Inhibition of GTP hydrolysis carried out by elongation factor-2 (EF-2).
17%
Inhibition of the activity of the enzyme, chitin synthase
69%
Interaction with fungal ergosterol to form pores in the fungal cell
4%
Inhibition of the activity of the enzyme, B-glucan synthase
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Régarding the structure and reproduction of fungi, which one of the following in most accurate?
Anonymous Quiz
10%
Peptidoglycan is an important component of the cell wall of fungi.
12%
Molds are fungi that grow as single cells and reproduce by budding
12%
Some fungi are dimorphic (ic, they are yeasts at room temperature and molds at body temperature)
66%
The fungal cell membrane centains ergosterol, whereas the human cell membranc contains cholesterol
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Regarding fungal pathogenesis, which one of the following is most accurate?
A-Ingestion of Amanita mushrooms typically causes kidney failure.
B-The Host response to infection by the systemic fungi, such as
Histoplasma and Coccidioides, consists of granulomas formation
C-ingestiom of aflatoxin produced by aspergillus flavus can cause adenocarcinome in colon
A-Ingestion of Amanita mushrooms typically causes kidney failure.
B-The Host response to infection by the systemic fungi, such as
Histoplasma and Coccidioides, consists of granulomas formation
C-ingestiom of aflatoxin produced by aspergillus flavus can cause adenocarcinome in colon
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Pityriasis versicolor, all true except;
Anonymous Quiz
29%
Caused by Malassezia furfur
54%
It is chronic mild infection of the dermis
8%
Characterized by hyper and hypopigmented maculae
8%
Lesions usually oceur in the chest. upper back, arms and abdomen
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Piedra, all the following are true, except;
Anonymous Quiz
57%
It is nail fungal infection
9%
Characterized by firm irregular nodule formation
16%
Black piedra caused by piedra hortae
19%
White piedra caused by trichosporon beigelli