Dermatology

Question 1

How many layers of skin are there and what are they?

Answer 1

3 layers: epidermis, dermis, hypodermis (subcutaneous fat, subcutis)

Question 2

How many sub-layers are there in the epidermis?

Answer 2

5 sublayers: (Come Let's Get Sun Burned)
Stratum Corneum
Stratum Lucidum
Stratum Granulosum
Stratum Spinosum
Stratum Basalis

Question 3

Which layer of the epidermis contains stem cells?

Answer 3

stratum basalis

Question 4

What layer of the skin contains blood vessels, connective tissues, hair shaft?

Answer 4

Dermis

Question 5

This prevents paracellular movement of solutes between epithelial cells of the skin

Answer 5

tight junctions

Question 6

What proteins make up tight junctions?

Answer 6

cadherins and occludins

Question 7

This connects actin cytoskeletons of adjacent epithelial cells via cadherins

Answer 7

Adherens junction

Question 8

Loss of E-cadherin promotes what?

Answer 8

metastasis

Question 9

This provides structural support via intermediate filament interactions.

Answer 9

Desmosome (macula adherens)

Question 10

Desmosomes contain what kind of protein?

Answer 10

desmoglein

Question 11

Autoantibodies to desmogelin 1 gives rise to what dermatologic condition?

Answer 11

pemphigus vulgaris

Question 12

These provides electrochemical communication between cells and are made of connexons

Answer 12

Gap junctions

Question 13

These connect keratin in basal cells to underlying basement membrane

Answer 13

Hemidesmosome

Question 14

Autoantibodies to hemidesmosomes gives rise to which dermatologic condition?

Answer 14

Bullous pemphigoid

Question 15

These membrane proteins maintain the integrity of basolateral membrane by binding to collagen, laminin, and fibronectin

Answer 15

Integrin

Question 16

Increased thickness of stratum corneum

Answer 16

Hyperkeratosis

Question 17

Retention of nuclei in stratum corneum

Answer 17

Parakeratosis

Question 18

Separation of epidermal cells

Answer 18

acantholysis

Question 19

Epidermal hyperplasia (increase spinousum)

Answer 19

Acanthosis

Question 20

Decreased melanin production d/t decreased tyrosinase activity or defective tyrosine transport

Answer 20

Albinism

Question 21

Acquired hyperpigmentation associated with pregnancy

Answer 21

Melasma

Question 22

Irregular patches of complete depigmentation d/t destruction of melanocytes

Answer 22

Vitiligo

Question 23

What is the difference between albinism and vitiligo in terms of melanocytes?

Answer 23

Normal melanocyte number in albinism. Melanocytes are destroyed in vitiligo

Question 24

Erythematous, well0demarcated plaques with greasy yellow scales in areas rich in sebaceous glands (salt, face, periocular region)

Answer 24

Seborrheic dermatitis

Question 25

Colonization of pilosebaceous unit (comedones) and inflammation

Answer 25

acne

Question 26

What type of hypersensitivity is atopic dermatitis (eczema)

Answer 26

Type I hypersensitivity

Question 27

Allergic contact dermatitis is what type of hypersensitivity?

Answer 27

Type IV

Question 28

These are papules and plaques with silvery scaling

Answer 28

Psoriasis

Question 29

This refers to pinpoint bleeding when from exposure of dermal papillae and scales are scraped off

Answer 29

Auspitz sign

Question 30

Psoriasis is associated with what HLA?

Answer 30

HLA-C

Question 31

Inflammation of the skin characterized by erythematous plaques and pustules but no comedones

Answer 31

Rosacea

Question 32

Proliferation of squamous cells with pseudocysts

Answer 32

Seborrheic keratosis

Question 33

This is the rapid onset of multiple seborrheic keratosis

Answer 33

Leser-Trelat sign

Question 34

Leser-Trelat sign is indicative of what malignancy?

Answer 34

GI adenocarcinoma

Question 35

These are benign capillary skin papules found in AIDS patients caused by Bartonella infections. Frequently mistaken for Kaposi sarcoma, but has neutrophilic infiltrates

Answer 35

Bacillary angiomatosis

Question 36

Endothelial malignancy mostly affecting the skin, mouth, GIT, respiratory tract. Seen in patients with AIDS and organ transplant patients. Associated with HHV-8 and HIV

Answer 36

Kaposi Sarcoma

Question 37

Benign capillary hemangioma usually seen in middle-age adults and does not regress

Answer 37

cherry hemangioma

Question 38

Bening capillary hemangioma of infancy

Answer 38

Cherry hemangioma

Question 39

Very superficial skin infection with honey-colored crusts

Answer 39

Impetigo

Question 40

What are the usual causative agents for impetigo?

Answer 40

S aureus, S pyogenes

Question 41

This is an infection involving upper dermis and superficial lymphatics presenting with well defined and raised lesion between infected skin and normal skin

Answer 41

Erysipelas

Question 42

This is an acute, painful, spreading infection of the deeper dermis and subcutaneous tissues. Like impetigo but dermal and may progress to necrotizing fasciitis

Answer 42

Cellulitis

Question 43

How does staphylococcal scalded skin syndrome differ from toxic epidermal necrolysis?

Answer 43

S aureus A & B exfoliative toxins destroy keratinocyte attachments in stratum garnulosum only. In toxic epidermal necrolysis, epidermal-dermal junction is destroyed

Question 44

How do you differentiate pemphigus vulgarisms from bullous pemphigoid?

Answer 44

Immunoflourescence will show reticular pattern in pemphigus vulgarisms and linear pattern in bullous pemphigoid

Question 45

These are pruritic papules, vesicles, and bullae with deposits of IgA at tips of dermal papillae. Associated with celiac disease

Answer 45

Dermatitis herpetiformis

Question 46

This is characterized by bullae formation, necrosis, and sloughing of skin at dermal-epidermal junction and usually associated with adverse drug reaction

Answer 46

Stevens-Johnson Syndrome

Question 47

This is epidermal hyperplasia causing symmetric, hyperpigmented thickening of the skin, especially in the axilla and neck. Associated with insulin resistance and visceral malignancy (gastric adenoCA)

Answer 47

Acanthosis nigricans

Question 48

``` 6Ps: Pruritic Purple Polygonal Planar Papules Plaques ``` Associated with Hep C

Answer 48

Lichen Planus

Question 49

"herald patch" with a "Christmas tree" distribution

Answer 49

Pityriasis rosea

Question 50

This is the most common skin cancer commonly with telangiectasia and rolled borders. More common in the upper lip

Answer 50

Basal cell CA

Question 51

Which skin malignancy has a histopathologic feature nuclei arranged as "palisading"

Answer 51

Basal cell CA

Question 52

This is a rapidly growing dermatologic lesion that resembles SCCA and presents as dome-shaped nodule with keratin-filled center and spontaneously regress.

Answer 52

Keratoacanthoma

Question 53

What is the associated mutation in melanoma?

Answer 53

BRAF kinase

Question 54

This is an ulcerated nodular mass usually seen on face and lower lip with histopatholig feature of keratin perals

Answer 54

SCCA