Fungi

Question 1

Identify the major virulence/toxicity factors associated with Penicillium. (1)

Answer 1

fungal spores have mycotoxins

Question 2

Describe a typical Tinea lesion. (2)

Answer 2

pruritic lesion with central clearing resembling a ring.

Question 3

What is the presentation of Blastomyces dermatiditis infection? (3)

Answer 3

gilchrist’s disease (blastomycosis)-mild infection in the lungs followed by ucerative granulomas of the skin or bone if infection becomes disseminated.

Question 4

How are coccidioldomycosis and histoplasmosis transmitted?

Answer 4

inhalation of asexual spores

Question 5

What is the morphology of C. albicans in culture at 37 degrees C?

Answer 5

germ tubes

Question 6

What lab findings are useful to help diagnose Histoplasma capsulatum? (2)

Answer 6

chest x-ray shows ‘millet seed’ pattern; Hyphae visible if cultured on Sabouraud’s agar.

Question 7

What lab findings are useful to help diagnose Pneumoncystis carinii? (2)

Answer 7

organism seen in microscopic examination of lung tissue or lavage; sputum cultures negative

Question 8

What is the morphology of Aspergillus fumigatus?

Answer 8

mold with septate hyphae that branch at a V-shaped (45 degree) angle

Question 9

What is the morphology of Rhizopus?

Answer 9

white ‘cotton candy’ colonies that turn brown with age

Question 10

Is Cryptocuccus neoformans domorphic?

Answer 10

no

Question 11

How is Coccidiodes immitis transmitted?

Answer 11

inhaled as spores

Question 12

What predisposes to disease with Pneumocystis carinii?

Answer 12

most infections asymptomatic. Immunosupression (e.g., AIDS) predisposes to disease.

Question 13

What regions are associaed with Histoplasma capsulatum? (2)

Answer 13

endemic to Ohio and Mississippi river valleys

Question 14

How is Histoplasmosis capsulatum transmitted?

Answer 14

bird or bat droppings

Question 15

What are the clinical manifestations of Cladosporium? (2)

Answer 15

allergic reactions to spores. Opportunistic lung infections possible in immunocompromised patients.

Question 16

What are the clinical manifestations of Alternaria?

Answer 16

allergic reactions and hypersensitivity pneumonitis to spores

Question 17

What disease does Pneumocystis carinii cause?

Answer 17

causes pneumonia (PCP)

Question 18

What is ‘most common’ associated with Cladosporium?

Answer 18

maybe the most common source of indoor and outdoor spores.

Question 19

What is the morphology of C. albicans in culture at 20 deg C?

Answer 19

budding yeast with pseudohyphae

Question 20

Identify the major at risk population associated with Pneumoncystis carinii.

Answer 20

aIDS and other immunosupressed patients

Question 21

Identify relevant epidemiology and risk factors associated with Candida albicans. (2)

Answer 21

aIDS, diabetes mellitus

Question 22

What is the morphology of Stachybotris?

Answer 22

black slimy mold

Question 23

What is the morphology of Histoplasma capsulatum?

Answer 23

dimorphic fungus (yeast/mold)

Question 24

What are the clnical manifestations of Cryptococcus neoformans? (2)

Answer 24

only causes diseases in immunocompromised. Meningitis insidious presentation-occasional headache, irritability, difficult cognition, mild fever. Relapse common.

Question 25

Is Aspergilius fumiatus dimorphic?

Answer 25

no

Question 26

What are the clinical manifestations of Aspergillus? (5)

Answer 26

ottitis externa; fungal sinusitis; allergic bronchopulmonary aspergillosis; fungus ball; sepsis

Question 27

What type of budding patter is seen in Cryptococcus neoformans?

Answer 27

narrow-based unequal budding

Question 28

What are the clinical manifestations of Pullalaria?

Answer 28

allergic reaction to spores

Question 29

What are the clinical manifestations of Tinea?(3)

Answer 29

ringworm-pruritic papules, broken hair, thick broken nails

Question 30

Describe the morphology of Blastomyces dermatiditis as revealed by KOH prep.

Answer 30

kOH preparation shows round double refractive wall with single broad-based budding yeast.

Question 31

What special lab test does the capsule of Cryptocuccus neoformans permit?

Answer 31

latex agglutination test detects polysaccharide capsular antigen

Question 32

What disease does C. albicans cause in immunocompromised patients?

Answer 32

Oral thrush in throat (neonates, steroids, diabetes, AIDS)

Question 33

What is the morphology of Cryptococcus neoformans?

Answer 33

heavily encapsulated yeast

Question 34

What lab findings are useful to help diagnose Cryptococcus neoformans? (6)

Answer 34

urease positive; encapsulated; spinal tap reveals pleocyosis, increased lymphocytes, low glucose, and organism that can be cultured.

Question 35

Cryptococcus neoformans stains best with which substance?

Answer 35

india ink

Question 36

What disease does C. albicans cause in babies?

Answer 36

diaper rash

Question 37

What region is associated with Coccidioides immitis?

Answer 37

endemic in the southwest US

Question 38

Is C. albicans, infection local, systemic, or both?

Answer 38

both

Question 39

What class of organism is Pneumocystis carinii?

Answer 39

yeast (originally classified as protozoan)

Question 40

What are the clinical manifestations of Candida albicans? (3)

Answer 40

thrush-white patches on red base can be scraped off. Candidal vaginitis-erythema, white discharge, itching and burning. Red patches with satellite pustules. Chronic mucocutaneous candidiasis-multiple red, pustular or thick lesions, esp on face.

Question 41

What are the clinical manifestations of Penicillium?

Answer 41

allergy (spores); penicilliosis (in AIDS)

Question 42

What do you culture Cryptococcus neoformans on?

Answer 42

culture on Sabouraud's agar

Question 43

What lab findings are useful to help diagnose Coccidioides immitis? (3)

Answer 43

tissue and sputum samples show spherules; XCR shows coin-shaped lesions; Serum will show specific antibodies

Question 44

Why is the disease caused by Coccidioidomycosis called valley fever?

Answer 44

common in the San Joaquin Valley

Question 45

What are the clinical manifestations of Mucor species? (2)

Answer 45

allergic reaction (spores); opportunistic infections of skin, sinuses in immunocompromised patients.

Question 46

Is H. capsulatum found intracellularly or extracellularly?

Answer 46

intracellular (frequently seen inside macrophages)

Question 47

Identify the major virulence/toxicity factors associated with Stachybotris. (1)

Answer 47

produces a toxin that can cause pulmonary hemorrhage if inhaled.

Question 48

What is the morphology of Mucor sp/? (2)

Answer 48

mold with irregular non-septate hyphae branching at wide angles (>90 deg). Large fluffy white colonies that turn gray or brown age.

Question 49

Other than thrush and vulvovaginitis, what other diseases can Candida albicans cause? (2)

Answer 49

disseminated candidiasis (to any organ) and chronic mucocutaneous candidiasis.

Question 50

Describe the symptoms of Coccidioides immitis infection. (7)

Answer 50

coccidioidomycosis (San Joaquin valley fever)-fever, cough, chest pain, sore throat, hemoptysis. In some patients, conjunctivitis, arthritis, erythema nodosum.

Question 51

What immune modifying diseases are most commonly associated wit infection with Mucor sp? (2)

Answer 51

ketoacidotic diabetics, leukemic patients

Question 52

Identify the major virulence/toxicity factors associated with Histoplasma capsulaturm. (1)

Answer 52

Macrophages eat spores which then bud into yeast intracellularly are transported all over the body.

Question 53

How is a stain of Pneumocystis carinii prepared?

Answer 53

silver stain of lung tissue

Question 54

What is the morphology of Alternaria?

Answer 54

dark green to brown 'velvet' colonies

Question 55

How does Candida albicans gram stain?

Answer 55

positive

Question 56

How is Histoplasma capsulatum transmitted?

Answer 56

spores inhaled with dust

Question 57

What is the major reservoir for Pneumoncystis carinii?

Answer 57

ubiquitous in the environment

Question 58

What is the major reservoir for Cryptococcus neoformans?

Answer 58

soil

Question 59

How is superficial fungal infections transmitted?

Answer 59

direct contact with other infected individuals

Question 60

What are the clinical manifestations of Stachybotris? (4)

Answer 60

nosebleeds, cough, chest congestion, may lead to infection and pulmonary hemorrhage.

Question 61

How is Pneumocystis carinii transmitted?

Answer 61

inhaled

Question 62

What is the morphology of Pullalaria?

Answer 62

white-pink colonies turn black as they age

Question 63

Which pulmonary disease is caused by Aspergillus fumigatus?

Answer 63

lung cavity aspergilloma (fungus ball)

Question 64

How is Cryptococcus neoformans transmitted?

Answer 64

inhalation of bird droppings (especially pigeon)

Question 65

Which peptide-containing media is useful for culturing fungi?

Answer 65

sabouraud's agar

Question 66

Identify the main risk factor associated with Cryptococcus neoformans.

Answer 66

immunosupressed individual

Question 67

What are the morphologies of Coccidoides immitis? (2)

Answer 67

mold in soil and spherule in tissues

Question 68

What is the morphology of Cladosporium?

Answer 68

colonies are powdery, black, brown or dark green.

Question 69

What are the major reservoirs for Histoplasma capsulatum? (2)

Answer 69

soil (mold form), animal tissues (yeast form).

Question 70

Are most fungal spores sexual or asexual?

Answer 70

asexual

Question 71

What lab findings are useful to help diagnose Tinea? (2)

Answer 71

hypae can be seen in skin scraping treated with 10% KOH; will fluoresce under UV light (wood's lamp)

Question 72

What disease does C. albicans cause in IV drug users?

Answer 72

endocarditis

Question 73

What are the clinical manifestations of Histoplasma capsulatum? (5)

Answer 73

histoplasmosis-upper respiratory tract infection may progress to pneumonia with progressive cough, night sweats, weight loss (compare TB). Also painless oral ulcers, hepatosplenomegaly and lymphadenopathy.

Question 74

What are the clinical manifesations of Rhizopus?

Answer 74

allergy (spores)

Question 75

What regions are associated with Blastomyces dermatiditis? (2)

Answer 75

found in the Mississippi river valley and parts of Africa

Question 76

What is the major risk factor associated with cladospourium?

Answer 76

old, wet buildings

Question 77

Identify relevant epidemiology and risk factors associated with Stachybotris. (2)

Answer 77

infants. cigarette smoke