Pathology - derm

Question 1

Layers of the epidermis

Answer 1

Corneum
Lucidum
Granulosum
Spinosum
Basale

Question 2

Claudins and occludins

Answer 2

Tight junctions

Question 3

Cadherins and action cytoskeleton

Answer 3

Adherens junction

Question 4

Keratin and desmoplakin

Answer 4

Desmosome

Question 5

Connexons

Answer 5

Gap junction

Question 6

Keratin and basement membrane

Answer 6

Hemidesmosome

Question 7

Integrins

Answer 7

Membrane proteins that attach to basement membrane

Question 8

Hyperkeratosis

Answer 8

incr. thickness of stratum corneum

Question 9

Acanthosis

Answer 9

Epidermal hyperplasia (incr. spinosum)

Question 10

Normal melanocyte number with decr. melanin production

Answer 10

Albinism

Decreased tyrosinase activity, or defective tyrosine transport

Also caused by failure of neural crest migration during development

Question 11

Autoimmune destruction of melanocytes

Answer 11

Vitiligo

Irregular areas of complete depigmentation

Question 12

Inflammation of pilsebaceous unit

Answer 12

Acne

Question 13

Pruritic eruption on flexor areas

Answer 13

Atopic dermatitis (eczema)

Face in infancy, then elbow fossa

Question 14

Acanthosis with hyperkeratosis

Answer 14

Psoriasis

incr. spinosum, decr. granulosum (SSSS: soriasis, spinosum)

Pinpoint bleeding when scales are scraped off - Auspitz sign

Question 15

Squamous epithelial proliferation with keratin-filled cysts

Answer 15

Seborrheic keratosis

If sudden appearance of multiple, then indication of underlying GI/lymphoid cancer

Question 16

Location of edema in urticaria

Answer 16

Dermis

look for lymphatic dilation as well. Mediated by mast cell degranulation

Question 17

Staph scalded skin syndrome

Answer 17

Exotoxin destroys keratinocyte attachments in granulosum only

heals completely

Question 18

Toxis epidermal necrolysis

Answer 18

Destruction of epidermal-dermal junction

Question 19

IgG antibody against desmoglein (desmosome component)

Answer 19

Pemphigus vulgaris

Acantholysis, flaccid intraepidermal bullae

Question 20

IgG antibody against hemidesmosome

Answer 20

Bullous pemphigoid

linear immunofluorescence at epidermal-dermal junction (Abs are “bullow” the epidermis)

Question 21

IgA at tips of dermal papillae

Answer 21

Dermatitis herpetiformis

Assoc. with celiac disease

Question 22

Associations with acanthosis nigricans

Answer 22

hyperinsulinism

gastric adenocarcinoma

Question 23

Sawtooth infiltrate of lymphocytes at dermal-epidermal junction

Answer 23

Lichen planus

assoc. with hep C

pruritic, purple, polygonal planar papules and plaques

Question 24

UVA vs. UVB rays

Answer 24

UVA - tanning, photoaging

UVB - sunburn

Question 25

Pink pearly nodules with telangiectasias, rolled borders, central crusting

Answer 25

Basal cell carcinoma Palisading nuclei

Question 26

Ulcerative red lesions with frequent scale, may spread to lymph nodes

Answer 26

Squamous cell carcinoma Keratin pearls

Question 27

Activating mutation in BRAF kinase, V600E

Answer 27

Melanoma Tx: vemurafenib