DD-Dermatology and the Epidermis Flashcards Preview

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Flashcards in DD-Dermatology and the Epidermis Deck (59):
1

the structure and functions of the skin

Skin is the largest organ

2

Fitzpatrick Skin Types

1- Never tans, always burns
2- Tans with difficulty, usually burns
3- Average tanning, sometimes burns
4- Easily tans, rarely burns
5- Very easy to tan, very rarely burns
6- Never burns

3

Top 5 Skin Diseases

Eczema
Acne
Bacterial skin diseases
Viral
Urticaria

4

melanocyte pigment cells which produce melanin packaged in granules called_________to protect from UV light

melanosomes

5

black to brown pigment

Eumelanin

6

yellow to red-brown pigment

Pheomelanin

7

melanosomes smaller and distributed in clusters above the nucleus in the keratinocyte

Light Skin

8

melanosomes larger and distributed individually throughout the cytoplasm of the keratinocyte

Dark Skin

9

1- Never tans, always burns
2- Tans with difficulty, usually burns
3- Average tanning, sometimes burns
4- Easily tans, rarely burns
5- Very easy to tan, very rarely burns
6- Never burns

Fitzpatrick Skin Types

10

DUE TO TYPE OF MELANIN PRODUCED, AS WELL AS SIZE AND DISTRIBUTION OF MELANOSOMES

Skin Pigmentation

11

ABSENCE OF MELANOCYTES

Vitiligo

12

-Decoration/Beauty
-Barrier
-Vitamin D synthesis
-Water Homeostasis
-Thermoregulation
-Insulation/Calorie Reservoir
-Touch/Sensation

Functions of the Skin

13

Dark Skin

melanosomes larger and distributed individually throughout the cytoplasm of the keratinocyte

14

Light Skin

melanosomes smaller and distributed in clusters above the nucleus in the keratinocyte

15

Autoimmune destruction of melanocytes

Acquired depigmentation

Commonly seen in periorificial and acral locations

Microscopic finding is a complete absence of melanocytes

Vitiligo
ABSENCE OF MELANOCYTES

16

-Water Homeostasis
-Thermoregulation
example?

Sweat

17

Vitamine D can come from?

Diet
UVB/skin

18

Epidermis

the outer layer of cells covering an organism

19

Base of Epidermis

Melanocytes

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Langerhans Cell

APC of Epidermis

21

Innermost layer of the epidermis
Contains small round cells called basal cells
Location of Stem Cells

BASAL CELL LAYER

22

Attachment point of basal cells to the basal lamina of the dermal epidermal junction

Hemidesmosomes

23

predominant cell type in the epidermis, the outermost layer of the skin, constituting 90% of the cells found there.

KERATINOCYTES

24

acute or chronic autoimmune skin disease, involving the formation of blisters

Bullous Pemphigoid

AB to Hemidesmosomes

25

Appears spiny due to the fact that the cells are held together with spiny projections.

The thickest layer of the epidermis, just above the basal layer

Stratum Spinosum SPINY CELL LAYER

26

______ produce keratin, a tough protective protein that makes up the majority of the structure of skin, hair and nails.

Keratinocytes

FORM SKIN BARRIER

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Desmosomes

attachment between Keratinocytes

28

Pathology: INTRAepidermal blisters

Pemphigus Vulgaris

29

Cells in this layer start to loose their nuclei

Prominent keratohyalin granules contain filaggrin which cross links keratin in the formation of the cornified cell envelop

Stratum Granulosum
GRANULAR CELL LAYER

30

Made up of dead and desquamating keratinocytes

Breakdown of filaggrin forms Natural moisturizing factor which binds H2O to keep skin moist

Stratum Corneum
CORNEOCYTE CELL LAYER

31

__________ is a filament-associated protein that binds to keratin fibers in epithelial cells

Filaggrin

w/o this, weak barrier. dry skin

32

Small cells associated with nerve endings in epidermis.  

seem to be involved in neural development and tactile sensation. 

Merkel cells

33

is only present in thick skin where it helps reduce friction and shear forces between the stratum corneum and stratum granulosum.

Stratum Lucidum
CLEAR CELL LAYER

34

Flat lesion

macule- small
patch- large

35

Raised Smooth lesion

papule
plaque
cyst
nodule

36

Raised Scaly lesion

papule with scale/plaque with scale

37

Fluid Filled lesion

vesicle/bulla/pustule

38

Redness lesion

erythema
erythroderma
telangiectasia

39

Purpura lesion

ecchymoses
petechiae
palpable purpura

40

Discrete, solid, elevated body
Less than 1.0 cm in diameter
May be further classified by surface change
Scale, Crust

Papule

41

Solid, flat-topped, elevated area of skin
Greater than 1.0 cm and broader than thick
May be further classified by surface change

Plaque

42

Firm and well-defined lesion
May be dermal or subcutaneous
Greater than 1.0 cm

Nodule

43

Surface Changes

Crust
Scale

44

Fluid filled cavity or elevation
Form within or just below epidermis
Less than 1.0 cm in diameter

Vesicle

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Fluid filled “blister”
Greater than 1.0 cm in diameter

Bulla

46

Circumscribed elevation that contains pus
Less than 1.0 cm in diameter
Color usually whitish-yellow

Pustule

47

Localized, blanchable redness
Caused by increased blood flow

Erythema

48

Generalized, blanchable redness

Caused by increased blood flow

May be associated with desquamation or extensive scaling

Erythroderma

49

Visible, persistent, dilation of small, superficial cutaneous blood vessels

Telangiectasias

50

Flat discoloration of skin or mucous membranes
Due to extravasation of blood
Color transitions over time and ranges from blue-black, brown-yellow, or green

Ecchymoses (Bruise)

51

Tiny 1-2mm (pinpoint spots)
Resulting from tiny hemorrhages
Color is red or violaceous

Petechiae

52

Raised and palpable discoloration

Due to vascular inflammation and extravasation of red blood cells (vasculitis)

Color is red or violaceous

Palpable Purpura

53

A thinning of epidermal, dermal or subcutaneous tissue

Atrophy

superficial or dermal

54

Localized loss of epidermal or mucosal epithelium
Causes can include injury or denuding of vesicle or bulla roof (removal)

Erosion

55

Circumscribed loss of epidermis and at least upper dermis

Ulcer

56

A deep linear crack or cleavage
Found in areas of thickened skin

Fissure

57

“Scab”
Adherent, thick, dry crust
Causes can include trauma, infection or excoriating skin disease
Color is black

Eschar (Crust)

58

Regions where opposing skin surfaces come in contact that may cause friction- Skin Folds

Extensive Distribution: Intertriginous

59

Pertaining to the skin surface overlaying muscles that flex joints, such as biceps

Flexural