Derm #1: Intro To Derm

Front 1

Primary vs. Secondary lesion

Back 1

Primary: physical changes caused directly by disease process (ex: macule, papule, tumor, plaque, vesicle, etc.)

Secondary: may evolve from primary or may be caused by external forces like trauma, itching, infection, or natural healing process. (ex: scale, crust, atrophy, ulceration)

Front 2

What type of lesion is this? Primary or Secondary?

Back 2

Macule (<0.5cm, flat, color change from skin, non-palpable)
Primary lesion

*macular hypopigmentation

Front 3

What type of lesion is this? Primary or Secondary?

Back 3

Macule, Primary

*vitiligo (macular depigmentation)

Front 4

What type of lesion is this? Primary or Secondary?

Back 4

Macule, Primary

*Cafe au lait

Front 5

What type of lesion is this? Primary or Secondary?

Back 5

Patch (flat with slight textural change, scaling/wrinkling).
Primary

*tinea versicolor

Front 6

What type of lesion is this? Primary or Secondary?

Back 6

Papule (elevated lesion, <0.5cm, palpable). Could be from hyperplasia of cells or cellular infiltrate. PRIMARY

*molluscum contagiosum (Pox virus)

Front 7

What type of lesion is this? Primary or Secondary?

Back 7

Papule, Primary

*seborrheic keratosis

Front 8

What type of lesion is this? Primary or Secondary?

Back 8

Papule, Primary

*acne, keloidalis nuchae

Front 9

What type of lesion is this? Primary or Secondary?

Back 9

Plaque (elevated lesion, >0.5 cm, palpable). Primary

This is PAPULOSQUAMOUS (plaques + papules + scales).

*psoriasis

Front 10

What type of lesion is this? Primary or Secondary?

Back 10

Plaque, Primary

*necrobiosis lipoidica

Front 11

What type of lesion is this? Primary or Secondary?

Back 11

Nodule: elevated, depth/diameter >0.5 cm, palpable (often round). Primary

*neurofibroma

Front 12

What type of lesion is this? Primary or Secondary?

Back 12

CRETERIFORM nodule (looks like crater), Primary

*keratoadenoma

Front 13

What type of lesion is this? Primary or Secondary?

Back 13

Nodule, Primary

*nodular melanoma

Front 14

What type of lesion is this? Primary or Secondary?

Back 14

Tumor: deeper, solid lesion, >2cm (can be benign or malignant). Primary

*leiomyosarcoma

Front 15

What type of lesion is this? Primary or Secondary?

Back 15

Wheal= Hive, edematous papule/plaque usually temporary. Results from dermal edema (no surface change).

Primary

*urticaria

Front 16

What type of lesion is this? Primary or Secondary?

Back 16

Annular wheal, Primary

Front 17

What type of lesion is this? Primary or Secondary?

Back 17

Vesicle (blister): small blister, fluid filled <0.5 cm. Can form from intracellular edema, lack of cohesion between cells or layers of skin. PRIMARY

*Herpes simplex

Front 18

What type of lesion is this? Primary or Secondary?

Back 18

Vesicle (blister): Primary

*herpes simplex (grouped vesicles)

Front 19

What type of lesion is this? Primary or Secondary?

Back 19

Vesicle, Primary

*Pemphigoid Gestationis (seen in pregnant people)

Front 20

What type of lesion is this? Primary or Secondary?

Back 20

Bulla: fluid filled blister that's >0.5 cm. Primary

Tense= does not easily rupture upon pressure vs. Flaccid (sagging)

*Tense bulla

Front 21

What type of lesion is this? Primary or Secondary?

Back 21

Flaccid Bulla, Primary

Front 22

What type of lesion is this? Primary or Secondary?

Back 22

Multiple tense and flaccid bullae, with surrounding urticarial plaques

*bullous pemphigoid

Front 23

What type of lesion is this? Primary or Secondary?

Back 23

Pustule: vesicle <0.5 cm, contains purulent (pus filled) material. Can be sterile or infectious. Primary

*pustular psoriasis

Front 24

What type of lesion is this? Primary or Secondary?

Back 24

Pustule, Primary

*pustules in acne vulgaris

Front 25

What type of lesion is this? Primary or Secondary?

Back 25

Cyst: sac with a wall (mainly epithelial) and lumen (filled with fluid/semisolid material). Typically malodorous. Primary

*epidermal cyst

Front 26

What type of lesion is this? Open vs Closed? Primary or Secondary?

Back 26

Comedo- primary lesion of acne. Follicule opening that is impacted by a plug of sebum/keratin. Open= blackheads (from oxidation), closed= whiteheads/fleshcolored

Front 27

What type of lesion is this? Primary or Secondary?

Back 27

Burrows: line like configurations produced by the scabies mite (lives in stratum corneum). Can be linear or serpiginous.

Front 28

What type of lesion is this? Primary or Secondary?

Back 28

Scale: abnormal accumulation/shedding of cornified cells. Visible flakes.

Desquamation= scales shedding in sheets.

*scalp psoriasis. SECONDARY

Front 29

What type of lesion is this? Primary or Secondary?

Back 29

Fish-like scale, Secondary

*ichthyosis vulgaris

Front 30

What type of lesion is this? Primary or Secondary?

Back 30

Desquamation (scales around the edge of bullae), Secondary

*bullous impetigo

Front 31

What type of lesion is this? What would you think if it was honey-colored, reddish-black, yellowish-green, or pure black?

Primary or Secondary?

Back 31

Crust: aka scab. Dried serum, blood, pus on skin admixed with cell debris. Secondary.

Honey colored= impetigo
Reddish black= hemorrhagic
yellowish-green= pus
Black= necrotic

*hemorrhagic crust from contact dermatitis

Front 32

What type of lesion is this? Primary or Secondary?

Back 32

Crust, Secondary

*impetigo (honey colored crusting)

Front 33

What type of lesion is this? Primary or Secondary?

Back 33

Necrotic crust (black) on grouped superficial ulcers, Secondary

Front 34

What type of lesion is this? Primary or Secondary?

Back 34

Erosion: depression that is moist or crusted. Results from PARTIAL loss of epidermis. Superficial and DOES NOT SCAR. (can also occur from scratching/ruptured blister).

SECONDARY

*vulvar erosion from herpes simplex

Front 35

Erosion vs. Ulcer

Back 35

Erosion: partial loss of epidermis, does not scar

Ulcer: complete loss of epidermis (may or may not involve dermal and subQ tissue). Heals with scarring.

Front 36

What type of lesion is this? Primary or Secondary?

Back 36

Ulcer, Secondary

- cause can be deduced from location (stasis ulcer, border ulcer), etc.

*Pressure ulcer from diabetic neuropathy

Front 37

What type of lesion is this? Primary or Secondary?

Back 37

Stasis/venous ulcer, Secondary

*from inflammation due to poor lymphatic return

Front 38

What type of lesion is this? Primary or Secondary?

Back 38

Ulcer with undermined border, Secondary

*pyoderma gangrenosum, has a classic violaceous border that is overhanging

Front 39

What type of lesion is this? Primary or Secondary?

Back 39

Excoriation- erosion caused by digging/ scratching (from fingernail). Secondary

*neurotic excoriation

Front 40

What type of lesion is this? Primary or Secondary?

Back 40

Acne excoriation, Secondary

*from picking at acne

Front 41

What type of lesion is this? Primary or Secondary?

Back 41

Fissure: linear depressed crack in the epidermis/ superficial dermis. ex: chapping hands. Secondary

*fissured eczema

Front 42

What type of lesion is this? Primary or Secondary?

Back 42

Fissure, Secondary

*fissure, angular stomatitis or chelitis

Front 43

What type of lesion is this? Primary or Secondary?

Back 43

Lichenification: area of thickened skin with accentuated lines, from rubbing/ scratching. Often seen in atopy (allergic rhinits, asthma, eczema).

Secondary

Front 44

What type of lesion is this? Primary or Secondary?

Back 44

Lichenification, Secondary

*lichen simplex chronicus

Front 45

Epidermal vs. Dermal and subcutaneous atrophy

Back 45

Epidermal atrophy: fine wrinkling associated with increased visibility of dermal vessels & striae (ex: from steroid use)

Dermal/subcutaneous atrophy: presents as significant depression or even dimpling of skin (ex: from injection site injury)

Front 46

What type of lesion is this? Primary or Secondary?

Back 46

Atrophy (depression of skin from thinning of one or more layers). Secondary

*striae from patient using steroids to treat tinea versicolor (ring worm)

Front 47

What type of lesion is this? Primary or Secondary?

Back 47

Atrophy, Secondary

*subcutaneous atrophy (from insulin injection)

Front 48

What type of lesion is this? Primary or Secondary?

Back 48

Atrophy (skin layers are thinning but still intact, unlike ulcer). Secondary

*radiation dermatitis with some telangiectasia (dilated vessels).

Front 49

What type of lesion is this? Primary or Secondary?

Back 49

Scar: healing response to injury, initially red/pink --> later white, atrophic, Secondary.

*hypertrophic/ keloid scar

Front 50

What type of lesion is this? Primary or Secondary?

Back 50

Ice-pick scars and depressed acne scars, Secondary

Front 51

What type of lesion is this? Primary or Secondary?

Back 51

Sclerosis (hardening or induration of skin) . Localized = morphea, generalized = scleroderma. Secondary.

*scleroderma

Front 52

What type of lesion is this? Primary or Secondary?

Back 52

Top= morpheus (localized hardening), Bottom= linear scleroderma. Secondary.

Front 53

What type of lesion is this? Primary or Secondary?

Back 53

Purpura: non-blanching erythema or redness or skin. From extravasated RBCs that have left vessels (so doesn't blanch with pressure).

*solar purpura (seen in elderly with lots of sun exposure)

Front 54

Petechiae vs. ecchymoses

What is palpable vs. non-palpable purpura?

Back 54

Non-palpable (macular)=
Purpura <3 mm= petechiae
purpura >3 mm are ecchymoses

Palpable purpura = vasculitis

Front 55

Describe the following distributions:

1. Acral
2. Intertriginous

Back 55

Acral= distal aspects of head, extremities (hands/feet)

Intertriginous= skin creases/ folds (axilla, gluteal, etc.)

Front 56

Describe the following distributions:

1. Lymphangitic
2. Photodistributed

Back 56

Lypmhangitic (Sporotrichoid)= along path of lymph channels of arms/legs

Photodistributed= found on sun-exposed skin (forehead, ears, nose, cheek, etc.

Front 57

What is the koebner phenomenon aka. isomorphic response?

Back 57

Development of skin lesions appearing along lines of trauma (ex: areas that are scratched)

*ex: koebnerized psoriasis caused by skin burn

Front 58

What does it mean for a lesion to have a "Zosteriform" distribution?

What about a "Herpetiform" distribution?

Back 58

Zosteriform: following linear/ dermatomas distribution (ex: herpes zoster/ shingles)

Herpetiform: grouped/clusters (ex: herpes simplex grouped vesicles)

Front 59

What is an "annular" distribution referring to?

What about "targetoid"?

Back 59

Annular= raised border with central clearing (ex: tinea corporis, or granuloma annulare)

Targetoid: target like with dusky center (can be seen in erythema multiforme).

Front 60

What type of distribution do you see? What is this condition (p-ANCA positive, damages heart and kidneys)?

Back 60

Reticulate or livedoid pattern (fixed vascular pattern).

This is polyarteritis nodosa

Front 61

What is the fixed format for describing a lesion?

What 2 things should you NEVER say?

Back 61

Distributed over/located on ______ (location), are __ (single, multiple) ___ (distribution) ___ (color) ____morphology _____ (primary lesion) _____ with (secondary changes)

Never say "erythematous" (say red, pink, violaceous). Never say "maculopapular".

Front 62

How would you describe this?

Back 62

Distributed on the axilla and trunk are multiple 0.3 to 2 cm tense vesicles and bullae, some on normal skin, and some on urticarial plaques.

= bullous pemphigoid

Front 63

How would you describe this?

Back 63

Located on the left medial cheek is a 1.5 by 1.3 cm translucent salmon-colored plaque with telangiectasia and central depression.

*basal cell

Front 64

How would you describe this?

Back 64

Located on the lateral trunk is a 4.5 cm by 5 cm, variagated black-brown plaque with a pink peripheral ulcerated nodule and a greyish hue.

*melanoma

Front 65

What are the layers of the epidermis (most superficial to deep)?

What are the layers of the dermis?

Back 65

Californians Love Girls in String Bikinis

Corneum --> Lucidum --> Granulosum --> Spongiosum --> Basale

Dermal-Epidermal Junction --> papillary dermis --> reticular dermis

Front 66

What layer of the epidermis has cells containing keratohyaline granules?

What layer has cells that contain tonofilaments?

Back 66

Stratum Granulosum- flat cells filled with keratinocytes and keratohyaline

Stratum Spinosum- tonofilaments (special intermediate filaments that are made into keratin)

Front 67

What layer of the skin is seen on H&E stain located at the area that the basement membrane of the epidermis would be (if seen on EM)?

Back 67

Dermal-Epidermal Junction (DEJ)

Front 68

What are the two layers of the dermis (which is superficial which is deep and how do they differ)?

Back 68

Superficial = Papillary layer (contains collagen fibrils that help anchor epidermis to dermis

Deep= Reticular layer= dense, irregular collagen and elastin.

Front 69

Dermal papilla vs. Rete pegs?

Back 69

Dermal papilla= papillary dermis that pushes up into stratum basales.

Rete pegs= stratum basalis that pushes down into papillary dermis.

Front 70

In what layer of the skin would you expect to find loose CT and mostly adipose tissue?

Back 70

Hypodermis (below dermis)

Front 71

Which cell is the sine qua non of the skin? How does it vary between the skin vs the hair/nails?

Back 71

Keratinocytes

The ones in the skin desquamate vs. the ones in the hair/nails which need to be cut

Front 72

T or F

People with darker skin have more melanocytes than people with light skin.

Back 72

False! They both have same number of melanocytes, it's just that darker people produce more melanin (pigment)

Front 73

What are merkel cells? What are langerhan cells?

Back 73

Langerhan= kidney bean shape, APC of the cell
Merkel= Neuroendocrine cell (not seen on H&E)

*both found in the Epidermis

Front 74

Where are apocrine and eccrine cells found? What else do you find in this layer?

Back 74

Dermis (also find fibro-elastic connective tissue and hair and vascular tissue- endothelium, nerves, sweat glands, sebaceous glands)

Subcutaneous tissue: adipocytes, loose CT

Front 75

What is acanthosis?

What is acantholysis and name a condition in which this is seen?

Back 75

Acanthosis: thickening of skin (epidermal hyperplasia)- seen in lichenified skin, psoriasis

Acantholysis: loss of intracellular bridges between cells resulting in epidermis falling apart (basal cells stay stuck). Seen in pemphigus vulgaris

Front 76

Where are hemidesmosomes located?

What disease results from auto-antibodies that target the hemidesmosomes?

Back 76

Located between epidermis basal layer and dermis (lamina lucida).

Bullous pemphigoid antigen is located in hemidesmosomes. Patients develop Bullous pemphigoid (tense vesiclesand bullae). Basal layer and epidermis ripped away from dermis.

Front 77

What important protein is targeted in Pemphigus vulgaris and what is its role?

Back 77

Desmoglein (glues adjacent cells together). Is attacked by auto-antibodies in pemphigus vulgaris.

Front 78

What condition is seen here and how can you distinguish this from other similar conditions?

Back 78

Pemphigus vulgaris

Note that the basal cells are still intact (because the hemidesmosomes are fine), bu the epidermal cells are separated from EACH OTHER (because desmosomes are affected).

Front 79

What condition is seen here and how can you distinguish this from other similar conditions?

Back 79

Bullous pemphigoid, you can make out that here, the entire epidermis is detached from the dermis but individual epidermal cells are intact with each other (i.e. hemidesmosomes are affected, not desmosomes)

Front 80

What is the difference between Bullous pemphigoid and Pemphigus vulgaris in terms of immunostain?

Back 80

Both have IgG and C3 deposits however-
1) Bullous pemphigoid is at basement membrane and linear
2) Pemphigus vulgaris is more mesh like

Front 81

Immunostain on an individual suffering from tense bullae and vesicles. What condition is it?

Back 81

Bullous pemphigoid (IgG and C3 deposits are linear and on basement membrane)

Front 82

Immunostain on an individual suffering from flaccid bullae. What condition is it?

Back 82

Pemphigus vulgaris (IgG and C3 and arranged in mesh like form)