Random Tidbits Flashcards
How do you diagnose allergic contact dermatitis?
Patch test
How do you treat allergic contact dermatitis?
Wash with water or Burow’s soln
Topical steroids
Where do infants get atopic dermatitis?
on cheeks, diaper area, extensors
Where do adults get atopic dermatitis?
flexor surfaces, hands, face, neck
How do you treat seborrheic dermatitis?
selenium sulfide/zinc/ketoconazole/cold tar shampoos
How do you remove crusts in seborrheic dermatitis?
warm oil and sulfur shampoos
What does stasis dermatitis look like?
edema, scaling, brown pigment, petechiae, ache in legs while standing
What is the mainstay of tx with stasis dermatitis?
compression socks
What does nummular eczema look like?
coin shaped plaques w/ papules on erythematous base c crusting
Where do people get dishydrotic eczema?
palms and soles
What does dishydrotic eczema classically look like?
tapioca pudding
deep clustered vesicles, papules, scaling, lichenification
How do you treat dishydrotic eczema?
wet dressings with burow’s, antihistamines
Does lichen simplex chronicus have:
a) papules?
b) plaques?
c) scaling?
a) no
b) yes
c) no!
What is the mainstay of tx for lichen simplex chronicus?
occlusive dressings to stop scratching
When do people get asteatotic dermatitis?
after hot baths, especially in the winter!
What is the pathophys of psoriasis?
keratin hyperplasia
inflamed cells
dilated blood vessels
Type 4 hypersensitivity
Where do people get plaque psoriasis?
trunk, scalp, extensors
What is pathognomonic of plaque psoriasis?
yellow-brown “oil spot” discoloration of nail beds
What sign will be + for plaque psoriasis and what is it?
Auspitz’s Sign
When you peel off a scale and it shows pinpoint bleeding
“50 y.o. man with no history of psoriasis has sudden bright red, scaling papules covering his entire torso and upper extremities. He reports having a cold a while ago that he just can’t seem to get over. What does this most sound like?”
this hx matches with guttate psoriasis
(buzz word = raindrop or splatterpaint)
Where do people get palmoplantar pustular psoriasis?
palms and soles
What is the mainstay of treatment for psoriasis?
Topical steroids
(Plaque = also Vitamin A/D)
(Guttate = also oral abx)
(PPP = also cover in plastic wrap)
Christmas tree pattern on torso
Herald Patch
Disease?
Pityriasis rosea
What is the tx for pityriasis rosea?
It’s self-limiting! 3-8weeks
Lotions, antipruritics
What infection is associated with lichen planus?
HCV
What are the 5 P’s of lichen planus?
purple
polygonal
planar
pruritic
papules
How do you dx fungal infections?
KOH prep will be +
beefy red with satellite lesions. what is it?
some sort of yeast infection
What is the tx for almost all mucocutaneous fungal inf? (thrush, vaginal, balanitis, candidal intertrigo)
topical nystatin
“Young pt returns from tropic area after tanning a lot and using lots of tanning oils with hypopigmented lesions”
tinea versicolor
(caused by malassezia furfur)
What does tinea versicolor look like on KOH prep?
spaghetti and meatballs
how do you tx tinea versicolor?
rx strength shampoo
What is the most common type of dermatophytes?
Trichophyton rubrum
How are dermatophytes transmitted?
fomites, animals, soil
Where is tinea pedis and what is the common term for it?
feet - Athlete’s foot
Where is tinea corporis and what is the common term for it?
trunk, arms, legs, neck
ringworm
How long should you continue topical antifungal tx for ringworm?
1-2 weeks after it has cleared
Where is tinea cruris and what is the common term for it?
upper thigh and groin
jock itch
How long do you continue tx for tinea cruris?
months to years
What disease is alopecia areata associated with?
alzheimer’s disease
What is pathognomonic for alopecia areata?
exclamation point hair
(the disease consists of round patches of hair loss)
How do you treat alopecia areata?
intralesional triamcinolone
systemic steroids but only a temporary fix
What is tinea unguium?
onychomycosis
fungus (trichophyton rubrum) of fingernails or toenails
Which type of onychomycosis is associated with immunocompromised?
Proximal Subungual Onychomycosis
Begins proximally on nail fold
What is the diagnostic testing for onychomycosis?
ALWAYS do lab testing to confirm!
*Histology of nail clipping
KOH, wet mount, or fungal culture
How do you tx onychomycosis?
only treat those with discomfort or immunocomp
oral terbinafine daily for 12 weeks
remission common
What is paronychia?
infection/abcess of lateral nail fold
How do you treat paronychia?
I+D with nerve block
local wound care, topical abx (bacitracin)
How do you tx lice?
topical insecticides (permethrin 1% cream rinse) once, then a week later
do head lice transmit ID?
do body lice?
no
yes
what do pubic lice look like?
brown grey specks
What do bedbug (cimex lectularius) bites look like?
papular utricaria
What will you see if you suspect scabies?
widespread skin-colored lesions
*burrows found at places without hair follicles (webs of hands, belt line, edge of socks)
*red papules/nodules on scrotum and shaft
How do you tx scabies?
permethrin 5% cream to all skin sites
also, oral ivermectin
treat partner
What causes generalized muscle pain, spasms, rigidity, and a target lesions?
black widow bites
How do you treat black widow bites?
pain: IV opioids or muscle relaxants
rigidity: IV calcium gluconate 10%
What causes progressive local necrosis, as well as fever, HA, malaise, arthralgias, nausea, and vomiting?
brown recluse bite
How do you treat a brown recluse bite?
local wound care, abx, oral steroids, excision
what is the patho of acne vulgaris?
plugged follicles lead to keratinization and retained sebum
leads to bacterial growth and release of fatty acid
What are the 4 grades of acne?
1: comedones
2: papulopustular
3: pustularnodular
4: nodulocystic
How do you tx acne?
benzoyl peroxide topical
topical abx
azeleic acid, glycolic acid, salycylic acid
topical retinoids (trenitoin)
etc
What are the 3 stages of rosacea?
- persistent red c telangectasia
- that + papules and pustules
- that + nodules, edema, and more severe sx
How do you tx rosacea?
topical metronidazole***
What is a brown to black plaque that is velvety and appears stuck on?
seborrheic keratosis
is SK benign or malignant?
benign
What appears as dry skin with a rough, erythematous border, caused by repeated exposure to the sun?
actinic (solar) keratosis
Is AK benign or malignant?
pre-malignant
How do you tx AK?
topical 5-fluorouracil 2x daily for 2-4 weeks
cryo or laser surg
What is an epidermal inclusion cyst?
cyst filled with cream-cheese like keratin
Looks like a nodule with a pearly border, telangectasia, and a central ulceration?
basal cell carcinoma
Where are you most likely to get BCC?
ear, face, neck
How do you dx BCC?
punch or shave bx
What is the tx of choice for BCC?
electric curettage
Does BCC spread fast or slow?
Does it metastasize?
slow
no
Appears as red, firm nodules, scaly with crusting.
Looks like unhealing sore, sometimes bleeds
squamous cell carcinoma
Does SCC spread fast or slow?
Does it metastasize?
slow
yes
How do you dx SCC? What will you see?
bx
large, pleomorphic, hyperchromic nuclei
What is a variant of SCC that is a dome-shaped nodule with a crater at the center?
keratocantoma
Does melanoma spread fast or slow?
Does it metastasize?
fast
yes
What is the most common type of skin CA?
BCC
How do you dx a melamona?
Full thickness bx
NOT a shave or punch bx!
Who gets Kaposi sarcoma?
HIV/immunocomp
What does erythema multiforme look like?
macules that become papules, with vesicles and bullae at center
target lesions
What manifestation of erythema multiforme is practically diagnostic?
mucosal lesions with pain, erosion
Pt. presents with sx of a URI, with cutaneous lesions on the trunk that are painful, sting, and burn. It started about 4 days ago as a rash, and now he has loose skin and blisters. There are also lesions on his mucosal surfaces. What sign will be +?
This is SJS or TEN
Nikolsky sign is +
Pt has had a rapid progression of local erythema and severe tenderness, and there appears to be ruptured bullae at the site that have turned black. Pt has a fever, tachycardia, hypotension, and an altered mental status. What will the labs look like?
This is necrotizing fasciitis
Triad: inc WBC, inc BUN, dec Na
Also get histopathologic, radiologic, and gram stain
what causes necrotizing fasciitis?
group A strep
How do you treat necrotizing fasciitis?
aggressive debridement
abx
Who gets necrotizing fasciitis?
It’s rare.
Immunocomp, DM, malignancy, C4 deficiency, some meds
Pt has systemic sx with a local warm, red and tender spot that has swelled up. It’s hard to distinguish where the lesion ends. Pt remembers having a cut in that spot last week. How will you treat?
This is cellulitis
Tx with abx (dicloxacilin, cephalosporin, macrolide)
Where do people get erysipelas?
face and lower extremities
What causes erysipelas?
group a strep
How do you treat erysipelas?
penicillin, macrolides
“honey colored crust” on child’s face
impetigo
How do you treat impetigo?
topical mupirocin [bactroban]
“gray to white tan, flat papules with rough, pebble-like surfaces”
verrucae
How will you dx verrucae?
Microscope: hyperplasia, hyperkeratosis, koilocytic squamous cells
immunofluorescence: HPV cells
How do you treat common verrucae?
salycylic acid, cryo, electrodecussation, imiquimod
or you could excise surgically
What strains of HPV cause
a) cervical ca?
b) common warts?
a) 16/18
b) 6/11
Pt. has a fever and sore throat. on PE, you notice vesicles on the posterior pharynx that have ruptured, leaving a gray exudate. Rapid strep test is negative. What do you suspect?
HSV1
How will the initial infection of HSV2 present?
pt has been very sick for a week
developed vesicles on genitalia with crusted, ruptured ulcers
What will you see on Tzank smear for HSV?
multinucleated giant cells
Pt has skin colored papules on his genitals, with a dome shape and a central umbilication that has white underneath the depression. He is sexually active. How will you treat this?
This is molluscum contagiosum.
It’s self-limiting, so you don’t need to treat.
If requiring tx, use imiquimod, cryo, curettage, retin-a
rash over 1 dermatome
varicella zoster
Pt. with DM has velvety hyperpigmentation. Where would you most likely find this hyperpigmentation?
Acanthosis nigricans
in the body folds
What is the #1 risk for melasma?
OCP! and pregnancy
how do you tx melasma?
skin-lightening creams like hydroquinone, azelaic acid
Pt. reports pain at the base of their spine, and on PE you notice swelling, redness, and draining pus at the PSIS. What causes this?
This is pilonidal disease
Cause by multiple ingrown hairs (probably)
Pt has pruritic wheals after eating shellfish that are worsened when scratching. What will diascopy show?
Utricaria
Diascopy shows it’s blanchable
How do you treat utricaria?
What type of hypersensitivity is it?
antihistamines, prednisone
type 1
How do you dx vitiligo?
Wood’s lamp
Pt has a tender abcess at the site of an apocrine gland (e.g. in her armpit). She is wondering what you can do for her.
It’s usually self-limited, so probably watchful waiting.
Look for S aureus and consider abx
How do you tx a stage 2-4 decubitus ulcer?
moise sterile gauze (Gelfoam)
hydrocolloid
debridement
Which degrees of burns have capillary refill?
1 and 2 (superficial)
Which degrees of burns have blistering?
2 (deep) and 3
Which degrees of burns have no pain
2 deep (no pain unless pressure)
3 and 4
Which degree of burn extends down through the dermis?
2nd (deep) and on
Which type of burn is moist?
2nd superficial
How do you care for burns?
clean with soap and water
debride
remove blisters only if they’ve ruptured
pain: acet, NSAIDs, +/- opioids
Abx (superficial = topical; silver sulfadiazine = 2nd/3rd)
press if not superficial
IVF
(ABCD PP fluids - abx, blisters, clean, debride, pain and press, IV fluids)
What looks like utricaria, but has large, tense bullae, and appears mostly in the elderly?
bullous pemphigoid
