Derm Review!!

Question 1

How long does it take for a stem cell to go from stratum basal is to stratum corneum?

Answer 1

28 days, ~1 month

Question 2

Desmosomes are located in the …?

Answer 2

Stratum spinosum, interlock keratinocytes

Question 3

Hemidesmosomes do what?

Answer 3

Lock epidermis to dermis

Made of Type 17 collagen!

Question 4

Dermal Layers

Answer 4

Top = Papillary dermis, interlocks with epidermal rete ridges
Bottom = Reticular dermis, has thicker collagen bundles

Question 5

Major constituents of the dermis

Answer 5

Collagen - TENSILE strength
Elastic fibers - resilience, SNAP BACK
Ground substance - facilitates diffusion

Question 6

Disorder of elastin?

Answer 6

Acquired = Solar elastosis!! duh
Congenital = PXE

Question 7

Blistering disorder of DEJ?

Answer 7

Acquired = Bullous pemphigoid (Ab at hemidesmosome)
COngenital = Junctional EB

Bullous (we said blistering). Remember congenital is EB (the kid in deem clinic)

Question 8

Describe adnexal structures

Answer 8

Sebaceous gland for gliding the hair follicle through
Smooth muscle = erector pili
follicle in subcut fat

Question 9

Hair cycle

Answer 9

Anagen = Grow, 3 yrs
Catagen = Transition, 3 weeks
Telogen = Resting, 3 months

THINK CELL CYCLE!! Ana = moves apart, Telo = chill in at either side. Cat is just weird, it’s in-between. But it’s transition, so its shortest

Question 10

Anagen effluvium vs. Telogen effluvium

Answer 10

Loss of GROWING hairs (chemo)

Loss of RESTING hairs (postpartum, meds)

Question 11

Acne vs RosaceaA

Answer 11

Acne: Hits oily areas, get comedones and blocked pores

Rosacea: FACE ONLY, erythematous disorder of central face, eyes in 1/4 pts, triggered by heat, cold, red wine, spicy foods, dilated vessels & flushing

Question 12

Types of Dermatitis

Answer 12

Nummular = round, coin shaped

Atopic = “the itch that rashes,” flexural areas, dx in childhood

Seborrheic = dandruff, cradle cap

Intertrigo = Irritant Dermatitis in skin folds

Question 13

Rash in flexoral area is a defect in…

Answer 13

Filaggrin, FILament, AGGregating protein in keratohyaline granules, important for barrier function of skin. As it breaks down, subcomponents are moisturizing factors for skin. These pts are more susceptible to atopic dermatitis and icthyosis

Question 14

What does Psoriasis look like vs. Atopic Dermatitis?

Answer 14

Psoriasis: Thick, scaly, silver plaques on EXTENSOR surfaces

Atopic: thinner, scaly, exematous patches on FLEXORAL surfaces (and face)

Question 15

What is Stasis Dermatitis?

Answer 15

Often seen with varicose vein and lower extremity edema, prior stasis ulcers

Question 16

What is Seborrheic Dermatitis?

Answer 16

Cradle Cap:

• Flaky, white to yellowish oily scale on scalp
• Can become confluent with a thick scale covering most of the scalp
• Begins 1 week after birth and may persist for several months

Facial involvement is usually symmetric over the medial eyebrows, nasolabial folds and ears
Occurs in areas rich in sebaceous glands (scalp, face, ears, chest).
Characterized by flaky,

Question 17

Types of HSR

Answer 17

I: IgE mediated, it binds Ag, cause degranulation of histamine from mast cells (hives, anaphylaxis)
II: IgG binds cell, lyses it via complement
III: IC Rxns, activate complement, inflamm cascade
IV: Allergic contact dermatitis, DELAYED HSR. Langerhans are APC and make memory T sensitized

Question 18

Atopic dermatitis leans toward what type of T cell rxn?

Answer 18

Environment & genetics makes immune system lean one way or another

Th2: makes eosinophils and IgE. DIFFERENT than allergic rxn

Question 19

Describe Impetigo

Answer 19

HONEY COLORED CRUST!!!

Question 20

Tinea Versicolor

Answer 20

Subtle, discolored, slightly scaly patch

Due to malazecia purpura, heterosporum (yeast)

Question 21

Scabies mite

Answer 21

–

Question 22

Keloid

Answer 22

Common in ear if you’re prone

Question 23

Erysipelas

Answer 23

Caused by STREP (treat w/ doxy)
Bright red, cliff-like drop off
Usually on face (also leg?)

Question 24

Sunburn from what UV band?

Answer 24

Mostly UVB.
Erythema action from C to B
Solar from B to A
UVA from tanning bed

Question 25

UV has what effects on skin?

Answer 25

Damage to DNA, RNA, lipids, protein
Pro inflammatory
Immunosuppressive
Induction of innate defenses
Induction of apoptosis
Vit D synthesis

Question 26

What are skin defenses to UVR?

Answer 26

DNA Repair machinery
Apoptosis of cells with DNA damage
Defenses against ROS
Melanin

Question 27

Rough gritty papule on field of sun damage?

Answer 27

Actinic Keratosis

Question 28

BCC has what defining feature?

Answer 28

Pearly rolled border, tumor of keratinocyte

Question 29

Biggest risk factor for melanoma?

Answer 29

FAMMM syndrome

Question 30

Sebaceous hyperplasia

Answer 30

From Sebocyte. More skin colored & yellow. Rolled border like BCC. Put into context w/ adjacent moles.

Question 31

What does squamous cell carcinoma look like?

Answer 31

Ulcerated lesion with hard, raised edges, derived from keratinocyte
Kerato-acanthoma: raised, dry, defined borders, pinkish

Question 32

Seborrheic Keratosis

Answer 32

Rough texture, stuck on, more brown, benign

Question 33

What is a flat <1cm color change? Larger?

Answer 33

Macule

Patch if larger

Question 34

What is a raiised, <1cm body?
Bigger?
More like plateau?

Answer 34

Papule = raised
Nodule = bigger
Plaque = plateau

Question 35

Cell types for hyperplasia?

Answer 35

Vascular tissue- cherry angiomas, hemangiomas, port wine stains

Keratinocyte- basal/squamous cell carcinomas, actinic keratosis, seborrheic keratosis

Fibroblast- dermatafibroma

Sebaceous gland- nevus sebaceous, sebaceous hyperplasia

Question 36

Common mutations leading to skin cancer and chemotherapeutic interventions

Answer 36

• BCC = patch1 mutation, vismodegib

* Melanoma = BRAF mutation, vemurafinib