Fungi

Question 1

Mycoses is what

Answer 1

fungal infections

Question 2

Cutaneous mycoses

Answer 2

infections of skin, nails, and hair

generally limited to keratinized layers, epidermis, and dermis (generally outer layers)

Question 3

Cutaneous mycoses - caused by

Answer 3

a group of organisms collectively referred to as dermatophytes (involve the skin)

Question 4

Cutaneous mycoses - causes by more than 2 dozen species of

Answer 4

More than 2 dozen species of microsporum, trichophyton, and epidermophyton
Capable of degrading and utilizing Keratin as a nutrient source

Question 5

Dermatophytes - 3 types

Answer 5

geophilic - found in soil
zoophilic - associated with animal contact
anthropophilic - person to person contact

Question 6

Dermatophytes - worldwide distribution

Answer 6

20% of US infected at any given time
more prevalent in warm moist areas
predisposing factors = closed shoes, community shower

Question 7

Dermatophytes - clinical syndromes typically evoke what

Answer 7

an inflammatory reaction involving underlying and surrounding tissue - circular lesions like ringworm are common

Question 8

Dermatophytes - clinical syndromes - infections are characterized by what

Answer 8

itching and scaling of the skin

secondary bacterial infections are common

Question 9

Dermatophytes - clinical syndromes - clinical manifestations of infection are often referred to as

Answer 9

Tinea (latin for worm)

Followed by a modifying word to describe the clinical manifestation or anatomical location

Question 10

Tinea pedis

Answer 10

Feet - “athletes foot”
Generally a chronic infection
Classic presentation is between tow webs (can also be on heel or side of foot and can spread to nails)
Secondary bacterial infection is common

Question 11

Tinea corporis

Answer 11

Torso, arms, and legs - “ring worm”
Classic presentation is a red, round, scaly patch with a raised border
Inflamed periphery with pustules
Can occur anywhere, but typically on trunk

Question 12

Tinea capitis

Answer 12

scalp, eyebrows, lashes
Scalp infection
Distinct scaly lesion
Patches of hair loss
Involvement of entire scalp 
Fungal elements can surround the hair shaft or be present within the hair shaft

Question 13

Tinea capitis - FAVUS

Answer 13

mass of hyphal elements surrounding the base of the hair shaft
caused by a certain species of trichophyton

Question 14

Tinea cruris

Answer 14

Groin
lesions present in the groin
90% occur in men
secondary infection is common

Question 15

Tinea unguium-onychomycosis

Answer 15

nails
infection of the nail plate and nail bed
hyperkeratosis and discoloration
dry, crackled, brittle, and disfigured nails
Common in pts with diabetes and AIDS
TX difficult because much deeper when in nail

Question 16

Diagnosis of dermatophytic infections

Answer 16

mostly on presentation

need to determine the why - determine source, confirm differential, and anticipate response to therapy

Question 17

Diagnosis of dermatophytic infections - hOW

Answer 17

direct observation of fungal elements in skin scrapings, nail or hair samples
Identification through culvitation

Question 18

Diagnosis of dermatophytic infections - Woods lamp

Answer 18

some species of microsporum will cause infected hairs to grow when held under UV light

Question 19

Tx of dermatophytic infections

Answer 19

may involve application of exfoliating agents as well as topical azoles
Azoles interfere with the synthesis of components of the fungal cell membrane

Question 20

Tx of dermatophytic infections - specifically capitis

Answer 20

griseofulvin is frequently used with capitis

Is thought to interfere with fungal cell division

Question 21

Tx of dermatophytic infections - specifcally unguium

Answer 21

difficult and may require long term administration of oral antifungals (which can lead to damage to internal organs)

Question 22

Candidiasis caused by

Answer 22

several yeast of the genus candida

Question 23

Most candidiasis infections are caused by

Answer 23

C albicans
Considered normal flora in skin, mucus membranes, GI tract
Also present in environment (doorknobs, carpet)

Question 24

Candida can exist in

Answer 24

yeast, pseudohyphal, and hyphal forms
Yeast = normal flora
Hyphal forms = tissue

Question 25

Cutaneous candidiasis are what? where do they occur?

Answer 25

skin and nail infections

body folds or areas that are moist or frequently become wet (diaper rash, dishwasher hands)

Question 26

Cataneous candidiasis - may present as

Answer 26

papules or confluent plaques

redness, tenderness, and cracking

Question 27

Chronic mucocutaneous candidiasis are what

Answer 27

superficial infections at several anatomical sites - mouth, face, finger nails

Question 28

Chronic mucocutaneous candidiasis - disease associated with

Answer 28

particular T cell deficits and endocrine disorders

Question 29

Chronic mucocutaneous candidiasis - response to infection

Answer 29

Granulomatous response to infection

disfigurement and discomfort

Question 30

Disseminated Candidiasis - Factors

Answer 30

Increase in colonization (due to disruption of normal flora)
Breakdown of normal physical barriers (burns, traums, catheterization)
Immune suppression

Question 31

Disseminated Candidiasis - At risk

Answer 31

Newborns
Surgery and burn patients
Transplant recipients
Patients receiving chemotherapy

Question 32

Disseminated Candidiasis - spread

Answer 32

hematogenous spread of organisms to liver, spleen, lungs, brain, eyes, bones, joints…

Question 33

Disseminated Candidiasis - tx

Answer 33

intravenous amphotericin B tx with or without fluconazole is current recommendation
Tx is challenging because can be toxic to patient