L3 Tinea Scabies

Question 1

Dermatophyte infections

Answer 1

Tinea Capitis
Tinea Corporis
Tinea Cruris
Tinea Pedis

Question 2

Tinea capitis

Answer 2

fungal infection
common in children, african-americans, decreased hygiene, etc
acquired via direct contact with individual or object
scaly patches w/ alopecia
black dots, widespread, kerion, favus

Question 3

Kerion

Answer 3

boggy edematous painful plaque

Question 4

favus

Answer 4

multiple cup-shaped yellow crusts (scutula) “honeycomb”

Question 5

assoc signs of tinea capitis

Answer 5

cervical adenopatchy
erthema nodosum
dermatophytid rxn: eczema like often after anti fungal therapy

Question 6

Dx of tinea capitis

Answer 6

physical exam
KOH prep
Dermoscope (see cork-screw hairs)
culture: slow
wood's lamp: meh

Question 7

tx of tinea capitis

Answer 7

Griseofulvin, systemic anti fungal for 6-12 weeks

topicals do not penetrate the hair follicle enough

Question 8

Tinea corporis

Answer 8

common in caregivers of children with t. capitis
athletes with skin to skin contact, t. corporis gladiatorum
immunocompromised
pruritic annular erythematous plaque
central clearing, raised border

Question 9

Dx of t. corporis

Answer 9

H&P
KOH prep
culture

Question 10

tx of t. corporis

Answer 10

topical antifungal
Clotrimazole at least 2 weeks
in special circumstances could use systemic anti fungal
itraconazole

Question 11

clomitrazole

Answer 11

topical antifungal

Question 12

itraconazole

Answer 12

systemic antifungal

Question 13

tinea incognito

Answer 13

tinea infection that is made worse b/c of topical steroid use. can cause local immune suppression allowing the fungus to proliferate

Question 14

majocchi’s granuloma

Answer 14

follicular and perifollicular dermatophyte infection of the deep dermis, and may be found in immunocompetent and immunocompromised people
aka using steroid cream

Question 15

tinea cruris

Answer 15

"jock itch"
begins in inguinal fold
contributing factors:
sweat/humidity
males
obesity
athlete's foot
occlusive clothes
well-marginated, scaly, annular plaque with raised border
scrotum is spared usually
pruritic and painful

Question 16

Dx of t. cruris

Answer 16

H&P
KOH prep
Culture

Question 17

tx of t. cruris

Answer 17

topical anti fungal
clotrimazole
resistant cases:
oral itraconazole

drying talcum powder
avoid tight clothes

Question 18

tinea pedis

Answer 18

most common dermatophytosis in the world
caused by occlusive footwear and communal showers
Acute and chronic forms

Question 19

acute t. pedis

Answer 19

itchy/painful vesicles/bulla following sweating
secondary staph infections can occur
usually self-limited, intermittent, and recurrent

Question 20

chronic t. pedis

Answer 20

slowly progressive infection that persists indefinitely
erosion/scales and fissures b/w toes
“moccasin ringworm”
tinea manuum

Question 21

moccasin ringworm

Answer 21

sharp demarcation with accumulated scale in skin creases

Question 22

tinea manuum

Answer 22

“vacuum for man”
jkjkjk
two feet & 1 hand infected

Question 23

dx of tinea pedis

Answer 23

H&P
KOH prep
Cuture
Gram stain if suspected bacterial infection

Question 24

tx of t. pedis

Answer 24

topical antifungal
clotrimazole x 4 weeks
oral anti fungal for chronic/extensive disease
itraconazole
burrow's wet dressings
treat secondary infections

Question 25

onychomycosis

Answer 25

infection of nail by fungus, yeast, or non-dermatophyte molds primarily cosmetic can be painful increases risk of concurrent infection distal, proximal, & white superficial subtypes,

Question 26

distal subungal onychomycosis

Answer 26

``` most common subtype usually toenails starts with big toe white/brown/yellow starting at distal corner and spreads toward cuticle nail breaks, exposing nail bed ```

Question 27

proximal subungual onychomycosis

Answer 27

starts near cuticle and progresses distally usually toenails uncommon immunocompromised (AIDS)

Question 28

white superficial onychomycosis

Answer 28

starts with dull white spots on nail plate usually toenails spreads centrifugally can be scraped for lab sample

Question 29

yeast onychomycosis

Answer 29

thickening of nail with yellow/brown discoloration usually fingernails may cause paronychia

Question 30

dx of onychomycosis

Answer 30

``` difficult to distinguish clinically KOH prep of nail scrapings culture histopathology (bx) most of the time fingernails carry yeast toenails carry dermatophytes ```

Question 31

tx of oncyhomycosis

Answer 31

not obligatory topical medications are usually ineffective oral terbinafine if dermophyte infection 6 weeks on fingernails 12 weeks on toenails oral itraconazole if non-dermatophyte infection 6 weeks for fingernails 12 weeks for toenails

Question 32

intertrigo

Answer 32

any infectious or non-infectious inflammatory condition of two closely opposed skin surfaces

Question 33

candidal intertrigo

Answer 33

risk factors: moisture, skin friction, immunocomp typically involves areas of the groin, mammary/abd folds, web spaces, and axilla erythematous, macerated (soggy) plaques and erosions satellite papules/putules fine peripheral scaling

Question 34

dx of c. intertrigo

Answer 34

H&P KOH prep Culture

Question 35

tx of c. intertrigo

Answer 35

topical medication nystatin cream systemic medication in severe cases itraconazole

Question 36

tinea versicolor

Answer 36

``` fungal infection of the normal skin flora that converts into mycelia form common in humid climates hyperhidrosis immunosuppressed NOT CONTAGIOUS macules, patches, plaques on trunk and upper extremity typically asymptomatic mildly pruritic variety of colors hypo/hyper/erythematous ```

Question 37

dx of t. versicolor

Answer 37

H&P KOH Wood's lamp

Question 38

tx of t. versicolor

Answer 38

``` topical anti fungal medications clotrimazole selenium sulfide (lotion/shampoo/foam) Zinc pyrithione (shampoo) systemic medications for extensive disease or failed topical treatment itraconazole pigment changes can last months after tx ```

Question 39

scabies

Answer 39

``` parasitic infection mite buries herself in the stratum corneum and lays 2-3 eggs/day x ~30days eggs hatch in 10 days can live without host for 3 days transmission through direct contact initial erythematous macule/papule burrow line is pathognomonic back and head are often spared of infestation severe pruritus, worse at night ```

Question 40

crusted scabies | norwegian scabies

Answer 40

presentation in immunocompromised pts fissures=avenue for bacteria, can lead to sepsis requires oral medications

Question 41

dx scabies

Answer 41

visualization of burrow microscopic identification of mites/eggs/feces dermatoscopy

Question 42

scabies tx

Answer 42

permethrin 5% cream initial dose followed by 2nd dose 10-14 days later oral ivermectin initial dose followed by 2nd dose 14 days later 2nd dose is necessary to kill any eggs that have hatched tx of pruritus with antihistamines and emoillants

Question 43

pubic lice

Answer 43

cause by crab louse can be seen with the naked eye most commonly affect teens and young adults via sexual contact pt presents with itching in the groin/axilla

Question 44

dx and tx of pubic lice

Answer 44

microscopy permethrin 1% cream, recheck/repeat in 10 days treat sexual partners 30% of pts will have a concurrent STI