STEP 1 Mycology 1

Question 1

All mycotic infections can cause _______ and have the ability to _______.

Answer 1

They all can cause pneumonia and can all disseminate

Question 2

Mycotic infections are all caused by what type of fungi?

Answer 2

Dimorphic fungi

Question 3

If the fungi exist/thrive at 20 degrees C they are called what? 37 degrees C?

Answer 3

at 20 they’re called Mold

at 37 they’re called yeast

Question 4

What fungi exists as a spherule in tissue and not a yeast?

Answer 4

Coccidioidmycosis

Question 5

Treatment for localized mycotic infections? (2 possibles)

Treatment for systemic mycotic infections? (1)

Answer 5

Fluconazole or itraconazole for local.

Amphotericin B for systemic

Question 6

Systemic mycoses can mimic ____ because mycoses cause _____.

Answer 6

Systemic mycoses can mimic TB because mycoses cause granuloma formation

Question 7

Even if systemic mycoses mimics TB, what does NOT happen in mycotic infections that does occur in TB?

Answer 7

There is no person to person transmission with mycotic infections

Question 8

Histoplasmosis:
Location
Causes what disease state
What do you see on microscopy
What are the sources of histo? (2)
Associated with?

Answer 8

Mississippi and Ohio River Valleys
Causes pneumonia
See macrophages laden with histoplasma (smaller than RBCs)
Bird or bat guano
Nickname is “Cave Disease” so spelunking probably

Question 9

Blastomycosis:
Locations (2)
Causes what exactly? What can form as a result?
What is seen on microscopy

Answer 9

States east of the Mississippi and Central America
Causes inflammatory lung disease and can disseminate to skin and bone. Forms granulomatous nodules (everywhere)
Broad-base budding on microscopy (same size as RBCs)

Question 10

What is the main difference between Histoplasmosis and blastomycosis?

Answer 10

Histoplasmosis mostly affects the lungs.

Blastomycosis starts in the lungs and disseminates everywhere (mostly skin, bone, lungs, and brain)

Question 11

Coccidioidmycosis:
Location
Causes (2)? Disseminates to (2)?
Cases increase after what?
A coccidioidmycosis spherule is filled with what?

Answer 11

SW U.S. and California
Causes pneumonia and meningitis is bad enough. Can disseminate to bone and skin.
Cases increase after earthquakes–> spores are thrown up in the air, inhaled, and become SPHERULES in the lungs.
Spherules (much larger than RBCs) are filled with endospores

Question 12

Paracoccidioidmycosis:
Location
What does it look like on microscopy?

Answer 12

Latin America

Budding yeast with “captain’s wheel” formation. Also much larger than RBCs

Question 13

Mneumonic for paracoccidioidmycosis

Answer 13

PARAcoccidio PARAsails with the CAPTAIN’S WHEEL all the way to LATIN AMERICA…boom

Question 14

Name 4 systemic mycotic infections

Answer 14

Histo, blasto, coccidioid, and paracoccidioid

Question 15

Name the only cutaneous mycotic infection STEP 1 cares about

Answer 15

Tinea versicolor

Question 16

Tinea versicolor:
Causative agent
Pathogenesis of the characteristic red patches

Answer 16

Malassezia furfur
The degradation of lipids produces acids that damage melanocytes and causes hypopigmentation and/or hyperpigmentation patches

Question 17

Tinea versicolor occurs in what type of climate?
Treatment (2)
What does it look like on microscopy?

Answer 17

1. Hot, humid, moist environments/weather
2. Topical miconazole or selenium sulfide
3. Looks like “spaghetti and meatballs” on microscopy

Question 18

Name three dermatophytes that can cause other tinea?

What do these dermatophytes cause?

Answer 18

Microsporium, Trichophyton, Epidermophyton.

They cause pruritic lesions with central clearing resembling a ring.

Question 19

If a KOH prep is done on dermatophytes, what is seen? What is NOT seen?

Answer 19

Mold hypahe is seen. They are not dimorphic

Question 20

Candida, aspergillus, cryptococcus, mucor, rhizopus, pneumocystis, and sprothrix are all examples of what?

Answer 20

Opportunistic fungal infections

Question 21

Candida causes which types of infections

Answer 21

Superficial or systemic fungal infections

Question 22

In terms of candida, what is seen in immunocompromised patients?

Answer 22

Oral and esophageal thrush

Question 23

Candida: what is seen in diabetics and recent antibiotic use?

Answer 23

Vulvovaginitis

Question 24

Candida: patients wearing diapers?

Answer 24

Diaper rash

Question 25

Candida: IV drug users?

Answer 25

Endocarditis

Question 26

Candida: worst possibilities (2)

Answer 26

Disseminated candidiasis

Chronic mucocutaneous candidiasis

Question 27

Candida treatment:
Vaginal (1)
Oral/esophageal (2 possible)
Systemic (3)

Answer 27

Vaginal: topical azole
Thrush: Fluconazole or caspofungin
Systemic: amphotericin B, fluconazole, or caspofungin

Question 28

Microscopy findings in candida

Answer 28

1. Dimorphic yeast
2. Pseudohyphae
3. Budding yeast

Question 29

Patient population to look for invasive aspergillosis:

Answer 29

Immunocompromised and those with chronic granulomatous disease

Question 30

You see bronchiectasis and eosinophilia in a patient with asthma (or CF). You notice “septate hyphae” that branch at 45 degrees…what do they have

Answer 30

Allergic bronchopulmonary aspergillosis

Question 31

A patient was just treated for TB infection and the infection cleared. The granulomas remain…what may be keeping the granulomas thriving?

Answer 31

Aspergillomas in the lung cavities

Question 32

Aflatoxins are detected in your patient’s urine. He has a history of hepatitis…what should you look for?

Answer 32

Some species of aspergillus produce aflatoxins which are associated with hepatocellular carcinoma
*The hepatitis bit isn’t in First Aid…I was just getting at a predisposition to HCC

Question 33

Microscopy findings for aspergillus?

Answer 33

***Septate hyphae that branch at 45 degrees

Not dimorphic

Question 34

What can cryptococcus neoformans cause: 2

Answer 34

1. Cryptococcal meningitis

2. Cryptococcosis

Question 35

What kind of yeast is cryptococcus? Dimorphic?

Answer 35

A heavily encapsulated yeast

Not dimorphic

Question 36

Where is cryptococcus found? How is it acquired and how does it disseminate?

Answer 36

Found in soil and pigeon droppings.

Acquired through inhalation with hematogenous spread to the meninges

Question 37

Best stain for cryptococcus neoformans?

Answer 37

India Ink stain dammit

Question 38

Microscopy findings in cryptococcus?

Answer 38

“Soap bubble lesions” in the brain

Wide capsular halos and unequal budding