Mycology

Question 1

List the 6 diseases associated with dermatophytes

Answer 1

1- tinea corporis 
2- tinea cruris 
3- tinea pedis 
4- tinea capits 
5- tinea ungunium
6- tinea manus

Question 2

what are the signs and diagnostic for tinea corporis

Answer 2

ringworm (trunk, arms, legs)

micro/macroconidia in scraping

Question 3

what are the signs of tinea cruris

Answer 3

jock itch (groin)

Question 4

what are the signs of tinea pedis

Answer 4

atheletes foot

Question 5

what are the signs of tinea capitis

Answer 5

ringworm of scalp

Question 6

what are the signs of tinea unguium

Answer 6

nail fungus

Question 7

what are the signs of tinea manus

Answer 7

ringworm of the hand

Question 8

list the 3 main groups of superficial fungal infections

Answer 8

1- piedras
2- dermatophytes
3- malassezia furfur

Question 9

_____ is caused by tinea blanca or trichosporon beigelii and is characterized by nodules on the hair- nodules are softer and pale in colors- only found on hair in groin and axillae

Answer 9

white piedra - superficial mycosis of hair

Question 10

______ is caused by piedra hortae

characterized by dark small nodules composed of spores and sacs seen on the hair shaft- mostly found in south america

Answer 10

black piedra- superficial mycosis of hair

Question 11

________ is a superficial mycosis that thrives on oily skin and has a characteristic spaghetti and meatballs appearance on microscopy.

Answer 11

Malassezia furfur

Question 12

_____ is a superficial mycosis that has distinct branch hyphae and causes pityriasis versicolor

Answer 12

malassezia furfur

Question 13

_____ grows as a mold (hyphae) in soil but switches to yeast in humans. it may be the only subcutaneous fungal infection in the US

Answer 13

sporothrix schenckii

Question 14

______ is one of the only subcutaneous fungi that can spread person to person or through sexual contact. this is a dimorphic fungi and is a common nosocomial infx

Answer 14

candida albicans

Question 15

list the 4 major systemic mycoses

Answer 15

1- histoplasma capsulatum
2- blastomyces dermatitidis
3- coccidiodes immitis
4- paracoccidiodes brasiliensis

Question 16

list the 5 major opportunistic infections (mycoses)

Answer 16

1- candida albicans 
2- cryptococcus neoformans 
3- aspergillus fumigatus 
4- mucor/rhizopus sp 
5- pneumocystis jirovecci

Question 17

a 44 y/o man w/ a h/o immunocomp illness presents c/o cough and general malaise. He states he recently was traveling in Mississippi and visiting various caves. You diagnose him with a mycosis that is noted to have a budding yeast appearance with a narrow base inside of the macrophages with a KOH stain. You also detect H antigen in his blood. What is the dx? How is this infection transmitted?

Answer 17

histoplasma capsulatum 
inhale spores (grows on bat guano/bird droppings)

Question 18

A patient is transferred to your infectious disease clinic c/o fever, night sweats and weight loss. You note a granulomatous ulcer across the skin. The patient states she was recently hiking in Virginia. Upon further diagnostics her bloodwork revealed Exo-A-Ag. What would a bronchial lavage show? Whats the dx?

Answer 18

bronchial lavage- large round double refractive wall with single broad base
Blastomyces dermatitidis

Question 19

what is the common geographical region and specific growth environment for blastomyces dermatitidis

Answer 19

east of MS river valley/ central america

organic debris- soil/rotten wood/ humid areas

Question 20

what is considered to be the most virulent systemic mycoses

Answer 20

coccidiodes immitis

Question 21

a landscaper from AZ c/o desert bumps, fever, productive cough, chest pain and extreme fatigue. you diagnose him with coccidiodes immitis- what is the method of transmission

Answer 21

inhalation of spherules

Question 22

a refugee patient from latin america presents c/o a facial rash. skin scrapes reveal multiple narrow based budding yeast cells that resemble steering wheels - what is the dx?

Answer 22

paracoccidiodes brasiliensis

Question 23

an HIV pt presents c/o nuchal rigidity and HA x 3 days - the culture reveals an encapsulated yeast - dx? what is the method of transmission?

Answer 23

crytococcus neoformans

inhalation (lives in pidgeon droppings)

Question 24

an HIV and Hep C + pt with a known history of IV drug abuse c/o dysphagia and substernal pain. Oral exam reveals oral thrush but you suspect esophageal thrush is present. what type of environment does this organism require for growth? what are the 3 forms it can appear in ?

Answer 24

pH alkaline 7.3

yeast/ pseudohyphae/ true hyphae

Question 25

this fungi is highly infectious in low doses- it only exists in body as a hyphal form (NO YEAST) and has tolerance to high temps
appearance is a flowering sporangium with finger like projections- V shaped branching septate hyphae

Answer 25

aspergillus fumigatus