Photomicrographs

Question 1

Answer 1

Tinea

Question 2

Answer 2

Pityriasis rosea

Question 3

Answer 3

INCONTINENTIA PIGMENTI

(IP), VESICULAR STAGE

Answer 4

Neutrophilic spongiosis

DDX:

• psoriasis
• subcorneal pustulosis
• AGEP
• dermatophytosis
• bacterial infections
• Reiter’s syndrome

Question 5

Answer 5

Chronic spongiotic dermatitis

Irregular or uneven hyperplasia, w/parakeratosis; spongiosis may be minimal

Question 6

Answer 6

Lichen simplex chronicus

Question 7

Answer 7

Lichen planus

Question 8

Answer 8

Toxic epidermal necrolysis

• EM minor: usually infections: HSV, mycoplasma
• EM major: usually drugs: sulfonamides, NSAIDs

Question 9

Answer 9

Acute GVHD

EM-like with

• vacuolar change
• dyskeratotic cells
• periadnexal infiltrates
• no/few eos (but presence does not rule out the dx)

Question 10

Answer 10

Lupus

Question 11

Answer 11

Dermatomyositis

Question 12

Answer 12

Lichen nitidus

Question 13

Answer 13

Lichen sclerosus et atrophicus

Question 14

Answer 14

Perniosis

Question 15

Answer 15

PLEVA

lymphocyte in every hole

vaculoar interface

compact stratum corneum +/- ulceration or crust

RBC extravasation

Transepidermal elimination of erythrocytes

Neutrophil margination within dermal vessels

Question 16

Answer 16

Pemphigus vulgaris

Question 17

Answer 17

Hailey-Hailey

Question 18

Answer 18

Pemphigus foliaceous

Question 19

Answer 19

Bullous pemphigoid

Question 20

Answer 20

Dermatitis herpetiformis

Question 21

Answer 21

Acantholytic dyskeratosis (Darier’s)

Question 22

Answer 22

Transient acantholytic dermatosis (Grover’s)

Question 23

Answer 23

Molluscum contagiosum

Question 24

Answer 24

Leishmaniasis

Question 25

Answer 25

Scabies

Question 26

Answer 26

GA

Question 27

Answer 27

NLD

Question 28

Answer 28

Rheumatoid nodule

Question 29

Answer 29

Pannciulitis

Question 30

Answer 30

Pancreatic fat necrosis

Question 31

Answer 31

LIPODERMATOSCLEROSIS

(SCLEROSING PANNICULITIS)

Question 32

Answer 32

DDX for needle shaped crystals in fat

• Sclerema neonatorum (lipocytes,min inflammation)
• Subcutaneous fat necrosis of the newborn (lipocytes and giant cells/inflammation)
• Post-steroid panniculitis (clinical hx)

Question 33

Answer 33

DDX for subcutaneous lymphoid follicles

• Lupus profundus
• Lymphoid hyperplasia B cell“pseudolymphoma”
• Chronic insect bite or drug reaction
• Marginal zone Bcell lymphoma

Question 34

Answer 34

Trichotillomania

Question 35

Answer 35

Alopecia areata

Question 36

Answer 36

Anagen, catagen, and telogen hairs

Question 37

Answer 37

Lichen planopilaris

Question 38

Answer 38

Scarring alopecia

Question 39

Vertical hair shaft

Answer 39

Question 40

Transverse hair shaft

Answer 40

Attach Images

Question 41

Answer 41

Telogen hair