Mycology Ii

Front 1

a. What agent causes pityriasis versicolor?

Back 1

i. Malassezia

(On a 10% KOH mount)

Hint 1

Front 2

b. What are the symptoms of pityriasis versicolor?

Back 2

i. Hypo- or hyperpigmented macules due to acid in melanocytes

Hint 2

Front 3

c. How can you ID pityriasis versicolor?

Back 3

i. Spaghetti and meatballs appearance of organisms in skin scrapings

Hint 3

Front 4

a. What agent causes tinea negra?

Back 4

i. Exophiala werneckii

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Front 5

a. What are the symptoms of tinea negra?

Back 5

i. Black macules on the skin

Hint 5

Front 6

c. How can you ID tinea negra?

Back 6

i. 2-celled oval yeast in skin scrapings

Hint 6

Front 7

a. What agent causes black piedra?

Back 7

i. PIedraia hortai

Hint 7

Front 8

b. What are the symptoms of black piedra?

Back 8

i. Black nodules on hair shaft

Hint 8

Front 9

a. What agent causes white piedra?

Back 9

i. Trichosporum beigelli

Front 10

b. What are the symptoms of white piedra?

Back 10

i. Crème-colored nodules on hair shaft

Front 11

a. What is the characteristic presentation of tinea?

Back 11

i. Ringworm lesion

Hint 11

Front 12

b. How can you ID tinea?

Back 12

i. Micro- and macroconidia scrapings from lesion

Hint 12

Front 13

2. What is the most common subcutaneous mycotic disease?

Back 13

a. Sporotrichosis

Hint 13

Front 14

a. What agent causes sporotrichosis/Rose-grower’s disease?

Back 14

i. Sporothrix schenckii

Hint 14

Front 15

b. What are the symptoms of sporotrichosis?

Back 15

i. Nodules and ulcers along lymphatics at site of inoculation

Hint 15

Front 16

c. How can you ID sporotrichosis?

Back 16

i. Cigar-shaped yeast in tissue exudate
ii. Converts to rosette pattern of conidiation on culture at 25 C

Hint 16

Front 17

a. What agent causes chromoblastomycosis?

Back 17

i. Fonsecaea

Hint 17

Front 18

b. What are the symptoms of chromoblastomycosis?

Back 18

i. Warty nodules that progress to cauliflower-like

Hint 18

Front 19

c. How can you ID chromoblastomycosis?

Back 19

i. Copper-colored spherical yeast called Medlar bodies

Hint 19

Front 20

d. Where is chromoblastomycosis usually found?

Back 20

i. Lower limbs

Front 21

a. What agents usually cause mycetoma?

Back 21

i. Pseudallescheria
ii. Madurella

Hint 21

Front 22

b. What are the symptoms of mycetoma?

Back 22

i. Draining sinus tracts at site of inoculation

Hint 22

Front 23

c. How can you ID mycetoma?

Back 23

i. White, brown, yellow, or black granules in exudate that are fungal colonies

Hint 23

Front 24

d. What is the name for a mycetoma infection in the foot?

Back 24

i. Madurella foot

Front 25

a. What agents cause mycotic keratitis?

Back 25

i. Fusarium
ii. Candida albicans

Hint 25

Front 26

b. How can you differentiate between fusarium and candida albicans?

Back 26

i. Fusarium→ cresecent-shaped macroconidia
ii. C. albicans→ pseudohyphae

Hint 26

Front 27

c. What are the symptoms of mycotic keratitis?

Back 27

i. Corneal ulcer
ii. Hypopyon→ pus in anterior chamber

Hint 27

Front 28

a. How can you contract histoplasmosis?

Back 28

i. Inhalation of macroconidia from soil at bird and bat roosts
ii. Causes a lung infection

Front 29

b. Where do you find macroconidia for histoplasma?

Back 29

i. Major Midwest river valleys

Front 30

c. What is the clinical presentation for histoplasmosis?

Back 30

i. Cough, chest pain, dyspnea, hoarseness
ii. Results in acute or chronic progress lug disease with calcifications

Hint 30

Front 31

d. How can you ID histoplasmosis?

Back 31

i. “Buckshot picture”
ii. 25 C→ tuberculate macroconidia
iii. 37 C→ Small yeast

Hint 31

Front 32

a. What agent causes North American blastomycosis?

Back 32

i. Blastomtyces dermatitidis

Hint 32

Front 33

b. What are the symptoms of North American blastomycosis?

Back 33

i. Granulomatous and suppurative lesions of lung with eventual skin lesions
ii. Resembles TB

Hint 33

Front 34

c. How can you ID North American blastomycosis?

Back 34

i. Thick-walled yeast with a broad base at 37 C

Hint 34

Front 35

d. Where are you most likely to contract North American blastomycosis?

Back 35

i. Major Midwest river valleys

Front 36

e. What will a CXR look like for North American blastomycosis?

Back 36

i. Mycoplasmic pneumonia

Hint 36

Front 37

a. What agent causes South American blastomycosis?

Back 37

i. Paracoccidioides brasiliensis

Hint 37

Front 38

b. What are the symptoms of South American blastomycosis?

Back 38

i. Initial lung disease with metastasis to skin and many organs

Hint 38

Front 39

c. How can you ID South American blastomycosis?

Back 39

i. 37 C→ yeast with multiple buds (can look like adenovirus or coronavirus)

Hint 39

Front 40

d. Where are you most likely to contract South American blastomycosis?

Back 40

i. Central and South America

Front 41

i. What are the symptoms of cutaneous blastomycosis?

Back 41

1. Dry, crusted, sharply circumscribed

Hint 41

Front 42

ii. What deficiency puts you most at risk for cutaneous blastomycosis?

Back 42

1. CMI deficiency

Front 43

a. What agent causes coccidioidmycosis?

Back 43

i. Coccidioides immitis

Hint 43

Front 44

b. What are the symptoms of coccidioidmyocis?

Back 44

i. Flu-like
ii. Initial pneumonia followed by erythematous skin rash
iii. Eventual skin ulcers and abscesses

Hint 44

Front 45

c. How can you ID coccidioidmycosis?

Back 45

i. Multinucleate spherule at 37 C→ fungus ball cavity in lung
ii. Septate hypae with arthropsores at 25 C

Hint 45

Front 46

d. Where are you most likely to contract coccidioidmycosis?

Back 46

i. SW US, Mexico

Front 47

e. To what areas of the body can coccidioidmycosis? How will it present there?

Back 47

i. Skin and bone
ii. Erythema nodosum
iii. Skin lesions
iv. Loss of L1-L2 disk space

Hint 47

Front 48

a. What agent causes cryptococcosis?

Back 48

i. Cryptococcus neoformans

Hint 48

Front 49

b. What are the symptoms of cryptococcosis?

Back 49

i. Mild lung infection
ii. Skin lesion
iii. Meningitis

Hint 49

Front 50

c. How can you ID cryptococcosis?

Back 50

i. Yeast with a large capsule

Hint 50

Front 51

d. What deficiency is associated with cryptococcosis?

Back 51

i. CMI deficiency

Front 52

e. Where are you most likely to contract cryptococcosis?

Back 52

i. Worldwide
ii. Pigeon roosts

Front 53

What agent causes pneumocystis pneumonia?

Back 53

Pneumocystis jiroveci

(An atypical fungus, which used to be classified as a protozoan)

Front 54

What are the symptoms of pneumocystis pneumonia?

Back 54

asymptomatic, (sub-clinical, latent, 75-90% incidence in kids); AIDS-associated interstitial pneumonia--> 85% of AID patients; malnourished or IC kids

Front 55

How do you ID pneumocystis pneumonia?

Back 55

Microscopy of silver or giemsa-stained samples of sputum, bronchial lavage, or lung tissue should show many cysts

Front 56

What are the symptoms of thrush (Candidiasis)?

Back 56

Creamy or cheesy growth at vagina, mouth, moist skin areas; also see endocardidits and GI disease

Hint 56

Front 57

What is the etiological agent of thrush (Candidiasis)?

Back 57

Candida albicans, candida glabrata

Front 58

How can you ID thrush (Candidiasis)?

Back 58

Germ tube formation in serum; chlamydospores on corn meal agar

(Also--> Dimorphic budding yeast, invasive septate hyphae, pseudohyphae in tissues

Front 59

Who is most susceptible to contracting thrush (Candidiasis)?

Back 59

Stressed, IC, or those missing normal flora

Front 60

What is the etiological agent of Aspergillosis (allergic bronchopneumonia)?

Back 60

Aspergillus fumigatus

Hint 60

Front 61

What are the symptoms of Aspergillosis (allergic bronchopneumonia)?

Back 61

"Fungus Ball" in tissue (paranasal sinus, lung, or brain)

Hint 61

Front 62

How can you ID Aspergillosis (allergic bronchopneumonia)?

Back 62

Morphology of asexual fruiting structures

Front 63

How is Aspergillosis (allergic bronchopneumonia) transmission?

Back 63

by inhalation

Front 64

What is the etiological agent of Zygomycosis?

Back 64

Rhizopus, Absidia, and mucor sp.

Front 65

What are the symptoms Zygomycosis?

Back 65

various, associated with diabetes; fungus ball in the eyes, sinuses, lungs, skin, or brain

Hint 65

Front 66

How can you ID Zygomycosis?

Back 66

Morphology of asexual fruiting structure and mycelium