Derm

Question 0

unique adverse drug reaction:

amoxicillin & concurrent EBV infection

Answer 0

=> “morbiliform”/maculopapular rash on torso,
w/ pruritis & eosinophils on histo
*ONE time rxn! bc of mono infection.
(other cutaneous drug reactions will occur every time take that med)

Question 1

Defn of urticaria

Answer 1

Well-defined dermal swelling, individual lesions last <24 hrs!

• acute = viral or allergy
• chronic = autoimmune or secondary to underlying disease

Question 2

Auspitz’s sign and Koebner phenomenon

Answer 2

BOTH = sign of Psoriasis (epidermal growth rate = too fast)

Auspitz: pinpoint bleed w/ removal of scaly plaque
Koebner: site of minor trauma = most commonly affected (ie: where hat rests on forehead)

Question 3

Psoriasis variants (3)

Answer 3

all = autoimmune rxn;

1. psoriatic arthritis (*HLA B27, = complication in 25% of psoriasis pts)
2. Impetigo Herpetiformis = pustular psoriasis of pregnancy
3. Guttate psoriasis = “splatter” on back, w/ strep infection

Question 4

Lichen Planus

appearance, assoc., risks

Answer 4

flat, dark papules on wrists & ankles; lymphocytes @ derm-epiderm j(x)
“P disease” bc Polygonal, Planar, Pruritic, Papular
* assoc. w/ HepC
** increased risk oral malignancy if EtOH or smoke exposure during active oral lesions!

Question 5

Lesler-Trelat Sign

Answer 5

sudden appearance of many sebhorrheic keratoses (waxy/greasy, “stuck on”); = sign of underlying malignancy!
*common in elderly/parkinson’s pts

** different from pre-malignant “actinic keratosis”

Question 6

Junctional vs. Intradermal nevus

Answer 6

= benign, “melanocytic”
Junctional = flat.
Intradermal = papular
* risk for malignancy if giant or atypical

Question 7

Dermatitis Herpetiformis

Answer 7

IgA deposition in tips of dermal papillae
=> pruritic papules/vesicles @ elbows.
Assoc. w/ Celiac disease!

Question 9

viruses that cause unique skin diseases (3)

Answer 9

1. parvo B19 - fifth’s disease/erythema infectuosum. (red cheeks, hydrops fetalis if pregnant)
2. Coxsackie A16 - Hand, Foot, Mouth disease
3. HHV-8 –> Kaposi’s sarcoma (purple lesions, look like chronic bruises)