Skin

Question 1

Macule

Answer 1

Flat lesion with well circumscribed change in skin color.

Freckle

Question 2

Patch

Answer 2

Big macule

Question 3

Papule

Answer 3

Elevated raised solid skin lesion (mole)

Question 4

Plaque

Answer 4

Big papule (like psoriasis)

Question 5

Vesicle

Answer 5

Fluid containing blister (chickenpox)

Question 6

Bulla

Answer 6

Large fluid containing blister

Question 7

Wheal

Answer 7

Transient smooth papule or plaque. (Hives)

Question 8

Scale

Answer 8

Flaking off stratum corneum

Question 9

Crust

Answer 9

Dry exudate (impetigo)

Question 10

Spongiosis

Answer 10

Epidermal accumulation of edematous fluid in intercellular spaces (eczema/hives)

Question 11

Acanthosis

Answer 11

Epidermal hyperplasia (acanthosis nigricans)

Question 12

Acantholysis

Answer 12

Separation of epidermal cells (pemphigus vulgaris)

Question 13

Albinism

Answer 13

Normal melanocyte number with a decrease in melanin production due to decreased tyrosinase or defective tyrosine transport. Can also be caused by failure of neural crest cells during development. Increased risk of skin cancer

Question 14

Melasma

Answer 14

Hyperpigmentation associated with pregnancy or OCP use.

Question 15

Vitiligo

Answer 15

Irregular areas of compllete depigmentation due to autoimmune destruction of melanocytes.

Question 16

Verrucae

Answer 16

Warts caused by HPV. Soft, tan-colored, cauliflower-like papules.

Question 17

Melanocytic nevus

Answer 17

Common mole. Benign, but melanoma can arise in congenital or atypical moles. Intradermal nevi in adults are papular. Junctional nevi are flat and in kids

Question 18

Urticaria

Answer 18

Hives. Pruritis wheals that form after mast cell degranulation. Characterized by superficial dermal edema and lymphatic channel dilation.

Question 19

Ephelis

Answer 19

Freckle. Normal number of melanocytes, increased melanin

Question 20

Atopic dermatitis

Answer 20

Pruritic eruption normally on flexor surfaces. Ossociated with asthma, allergic rhinitis. Usually starts of face in infacny and can appear in the anticubital fossa after.

Question 21

Allergic contact dermatitis

Answer 21

Type IV hypersensitivity reaction to nickle or poison ivy.

Question 22

Psoriasis

Answer 22

Associated with HLA-c. Papules and plaques with silver scale especially on knees and elbows. Acanthosis with retained nuclei in keratin (parakeratosis). Increased spinosum and decreased granulosum. Auspitz sign – pinpoint bleeding spots where dermal papillae are exposed.

Treat with corticosteroids or uva light

Question 23

Seborrheic keratosis

Answer 23

Flat greasy stick on proliferation of epithelium with keratin filled cysts. Looks like a stuck on lesion. Common in older people.

However, if many appear suddenly, that’s the leser trelat sign indicating a gi malignancy

Question 24

Impetigo

Answer 24

Very superficial skin infection usually from staph aureus or strep pyogenes. Very contagious. Honey colored crusting. Bullous impetigo is usually caused by staph aureus

Question 25

Cellulitis

Answer 25

Acute painful spresding infection of dermis from strep or staph. Can occur due to a break in skin.

Question 26

Scalded skin syndrome

Answer 26

From staph, usually a sloughing of the upper layers of the epidermis that heals completely.

Question 27

Pemphigus vulgaris

Answer 27

Autoimmune reaction to desmoglein (IgG) in spinosum. Causes intraepidermal bullae caused by acantholysis. INVOLVES ORAL MUCOSA. Antibodies around epidermal cells in a net-like pattern. Nicolsky sign is where the blusters will pop and separate easily. Basal layer still attached

Question 28

Bullous pemphigoid

Answer 28

Less severe than pemphigus vulgaris. Does not separate. Due to autoimmune antibody against hemidesmosomes. Spares oral mucosa. Linear anti basement membrane staning.

Question 29

Dermatitis herpetiformis

Answer 29

IgA depositing at dermal papillae. Pruritic. Associated with celiac and will disappear with gluten free diet.

Question 30

Erythema multiforme

Answer 30

Associated with mycoplasma, HSV, SLE, beta lactams. Causes macules, papules, vescles and target lesions with a dusky center with necrosis.

Question 31

Steven johnson's syndrome

Answer 31

Characterized by fever and erythema multiforme. Generally 2 mucous membranes are involved. Usually due to drug reaction

Question 32

TEN

Answer 32

Toxic epidermal necrolysis. More severe than SJS, seen when >30 percent of body surface in involved.

Question 33

Acanthosis nigricans

Answer 33

Thickening and darkening of skin associated with insulin resistance and gastric adenocarcinoma.

Question 34

Actinic keratosis

Answer 34

Premalignant lesions caused by sun exposure. Precursor to squamous cell carcinoma.

Question 35

Erythema nodosum

Answer 35

Painful inflammatory lesions in shins. Can be associated with sarcoidosis, fungal infections, crohn's disease

Question 36

Lichen planus

Answer 36

Pruritis, purple, polygonal, planar papules. Sawtooth infiltrate of lymphocytes at dermal-epidermal junction associated with HEP C!

Question 37

Pityriasis rosea

Answer 37

Herald patch followed by christmas tree rash. Self resolving

Question 38

Basal cell carcinoma

Answer 38

Frequently on upper lip. Most common. Caused by UVB induced sun damage so albanism and XP are at risk. Almost never metastasizes, but locally invasive. Has palisading nuclei

Question 39

Squamous cell carcinoma

Answer 39

On lower lip. Second most common. Associated with immunosuppression, arsenic exposure. Locally invasive, rarely metastasizes. Has keratin pearls. And associated with chronic draining sinuses.

Question 40

Keratoacanthoma

Answer 40

Variant of squamous cell carinoma. Cup shaped lesion filled with keratin. Grows rapidly

Question 41

Melanoma

Answer 41

S100 tumor marker because derived from neural crest. Asymmetric with irregular borders, irregular color, diameter >6mm, evolution oer time. Often activating mutations in BRAF kinase.