Derm

Question 1

Most common skin cancer in pts with chronic immunosuppresion?

Answer 1

Squamous cell carcinoma
Thick rough surface in sun exposed area
Can cause regional neuroligc syx (numbness)

Question 2

Teen being treated for acne has severe sun burn. What is in the med?

Answer 2

Doxycycline

Question 3

Pt has forearm lesion that has a smooth border but small eccentric nodule.
Next?

Answer 3

Excisional bx

“ugly duckling sign”

Question 4

Pathophys of vitiligo

Answer 4

Autoimmune destruction of melanocytes

Tx - steroids

Question 5

Pruritic rash on flexor surface of wrist, fingers

Itching worst at night

Answer 5

Scabies

Tx - TOP permethrin or po ivermectin

Question 6

Most common skin malignancy in US

Slow growing papule with pearly rolled border

Answer 6

Basal cell

Rarely metastasizes

Question 7

Condylomata acuminata

Answer 7

HPV of genitals/anus

Question 8

HPV 16/18

Answer 8

Squamous cell carcinoma of anus, genitalia, throat

Question 9

Guy bought a cheap watch and has a gnarly scaly rash on his wrist

Answer 9

Nickel allergy
Type IV hypersensitivity
Itching, scaling, lichenification
Tx - corticosteroids

Question 10

Acute infection of small papules with central umbilication

Answer 10

Malluscum contagiosum (poxvirus)
Self limited in healthy pts
Associated with HIV

Question 11

Ring shaped, scaly patches iwht central clearing and distinct borders x weeks

Answer 11

Tinea corpis (ringworm)
Dx -KOH prep
Tx - top antifungals, po if severe

Question 12

elderly woman with purpura and ecchymosa

NL studies

Answer 12

Senile purpura
d/t age related loss of elastic fibers in perivascular connective tissue
Benign

Question 13

Tx for basal cell carcinoma on the face?

Answer 13

Mohs surgery
thin lays are removed and inspected by path to ensure clear margns
Use in high risk lesions or delicate or cosmetically sensitive ares

Question 14

Dome shaped, firm, freely movable cyst/nodule with small central punctum

Answer 14

Epidermal inclusion cyst
Benign nodule containing squamous epitherlium that produces kerating
Can be stable or gradually increase in size +/- cheesy white discharge
Resolves spontaneously

Question 15

Pt has chronic diffuse dermal scaling

Skin appears dry and rough with horny plates

Answer 15

Icthyosis vulgaris
chronic, inherited
plates resemble fish or reptile scales
Mutation in filaggrin gene
Tx - emollient, keratolytics, topical retinoids

Question 16

Most common benign vascular tumor in adults

Answer 16

Cherry angiomas

Strawberry angiomas are only in kids

Question 17

Dandruff + greasy scaley face rash

Answer 17

Seborrheic dermatitis
1st year of life, and in middle aged
Associated with Parkinson and HIV
Tox - top antifungal

Question 18

etiology of plantar warts

Answer 18

HPV

Young adults, immunocompromised

Question 19

HCV pt develops vesicles, erosions of the dorsum of both hands after sun exposure

Answer 19

Porphyria cutanea tarda
Porphyrin accumulation d/t impaired metabolism (heme synthesis)
Deficiency of uroporphyrinogen decarboxylase

Question 20

Bullous dz

punch bx reveals linear IgG and C3 deposits and dermal-epidermal junction

Answer 20

Bullous pemphigoid
Associated with malignancy, neurologic disorders
IgG against hemidesmosome and basement membrane
Tx - TOP clobetasol

Question 21

Most common malignancy of lower lip

Answer 21

Squamous cell carcinoma

Bx - invasive cords of squamous cells with keratin pearls

Question 22

Pt with celiac develops skin rash over the butt. Dx?

Answer 22

Dermatitis herpetiformis
dermal rxn to dietary gluten
Clusters of pruritic papules and vesicles
tx - dapsone and GF diet

Question 23

Bullous dz

bx - immunofluoresence intracellular deposits of IgG

Answer 23

Pemphigus vulgaris

Antibody against desmosomes