Introduction to dermatology

Question 1

What is the largest organ in the body?

Answer 1

skin

Question 2

List some accessory structures of the skin

Answer 2

hair, nails, sensory structures

Question 3

Name the 2 layers of the skin

Answer 3

epidermis and dermis

Question 4

3 cell types found in the epidermis

Answer 4

keratinocytes (most)
Langerhans
melanocytes

Question 5

What composes the dermis?

Answer 5

collagen and elastin matrix with mucopolysaccharide gel

fibroblasts, sebaceous and sweat glands, hair follicles, macrophages, dermal dendritic cells

Question 6

What is the sub cutis? function?

Answer 6

fat energy store

insulation and anchor skin to fascia

Question 7

Function of melanocytes

Answer 7

make melanosomes (melanin) which is excreted and phagocytosed into keratinocytes to protect from UV exposure

Question 8

Role of Langerhans cells

Answer 8

Process antigens and migrate to LN to induce an immune response

Question 9

Name the 5 layers of the epidermis

Answer 9

stratum corneum 
stratum lucidium 
stratum granulosum 
stratum spinosum 
stratum basale

Question 10

What layer of epidermis has stem cells and the effect of this?

Answer 10

stratum basale

regenerative properties of the skin

Question 11

What layer of epidermis do cells become dead?

Answer 11

granulosum

Question 12

Functions of nail

Answer 12

protection

fine sensory and motor tasks

Question 13

Nail matrix

Answer 13

tissue the nail protects

Question 14

What part of the nail prevents the matric from becoming infected?

Answer 14

cuticle

Question 15

3 phases of hair cycles

Answer 15

anagen
catagen
telogen

Question 16

What hair phase is active?

Answer 16

anagen

Question 17

What hair phase is the resting phase?

Answer 17

telogen

Question 18

6 functions of the skin

Answer 18

thermoregulation
barrier 
interpersonal communication 
skin immune system 
vitamin D synthesis 
sensation

Question 19

5 D’s of why skin disease is important

Answer 19

disfigurement 
discomfort 
disability 
depression 
death

Question 20

External causes of skin disease

Answer 20

temperature 
chemical 
infection 
trauma 
UV

Question 21

Internal causes of skin disease

Answer 21

drugs
genetics
infection
systemic disease

Question 22

What is the main cause of photosensitivity?

Answer 22

medication
reactive to UVA/B and visible light
exposed sites affected

Question 23

Main clue with photosensitivity

Answer 23

areas under chin and behind ear unaffected

Question 24

Cold urticaria

Answer 24

skin reaction to cold due to mast cell degranulation

Question 25

dermatitis artefacta

Answer 25

burn, aerosol can, suction blister | self inflicted

Question 26

bullous pemphigoid

Answer 26

blisters at dermal-epidermal junction due to anti hemidesmosome antibodies

Question 27

Morphology

Answer 27

appearance of skin lesions

Question 28

What size does small mean?

Answer 28

less than 5mm

Question 29

macule

Answer 29

small circumscribed area

Question 30

patch

Answer 30

large circumscribed area

Question 31

papule

Answer 31

small raised area

Question 32

Plaque

Answer 32

large raised area

Question 33

vesicle

Answer 33

small fluid filled

Question 34

bulla

Answer 34

large fluid filled

Question 35

pustule

Answer 35

small pus filled

Question 36

abscess

Answer 36

large pus filled

Question 37

erosion

Answer 37

affecting epidermis - loss

Question 38

ulcer

Answer 38

loss of epidermis and dermis

Question 39

What is the difference between a macule/patch and normal skin?

Answer 39

colour ONLY

Question 40

What is a small and large intradermal haemorrhage called?

Answer 40

petechiae | purpura

Question 41

What can distribution of skin lesions tell us?

Answer 41

help with diagnosis eg solitary, symmetrical, multiple, general

Question 42

What is eruptive xanthoma indicative of?

Answer 42

hyperlipidaemia

Question 43

What is acanthosis nigracans linked to?

Answer 43

type 2 DM, obesity, malignancy

Question 44

How are cutaneous signs helpful in diagnosing?

Answer 44

can tell us about systemic illnesses and many other conditions eg malignancy, auto-immune, sarcoidosis

Question 45

How do we investigate bacterial dermatology?

Answer 45

charcoal swab swab exudate, ulcers etc (do blood test if none) microscopy, culture and sensitivity

Question 46

Viral investigations in dermatology

Answer 46

viral swab for PCR | swab vesicle/bulla if vesicular eruption

Question 47

If a viral infection is systemic how do we investigate in dermatology?

Answer 47

throat swab

Question 48

Fungal investigations

Answer 48

nail clippings hair sample skin clipping

Question 49

Skin biopsy uses

Answer 49

punch biopsy - 5mm radius | eczema, psoriasis, malignancy etc