Dermatitis/ Eczema

Question 1

What is hyperkeratosis

Answer 1

Increased thickness of keratin layer

Question 2

What is parakeratosis

Answer 2

Persistence of nuclei in the keratin layer

Question 3

What is acanthosis

Answer 3

Increased thickness of epidermis

Question 4

What is papillomatosis

Answer 4

Irregular epithelial thickening

Question 5

What is spongiosis

Answer 5

Oedema between keratinocytes

Question 6

What is inflammatory cell infiltrate

Answer 6

Acute or chronic lymphocytes and/ or neutrophils

Question 7

What is the main symptom/ sign of eczema

Answer 7

ITCH

Question 8

What happens in the acute phase of eczema

Answer 8

Papulovesicular
erythematous lesions
eodema / spongiosis
Ooze or scaling and crusting

Question 9

What happens in the chronic phase of eczema

Answer 9

Thickening (lichenification)
Elevated plaques
Increased scaling

Question 10

Drug related dermatitis shows what histologically

Answer 10

spongiotic dermatitis and eosinophils

Question 11

What is the pathogenesis of atopic dermatitis

Answer 11

Genetic and environmental factors resulting in inflammation

Question 12

What is the pathogenesis of contact allergic

Answer 12

Delayed type hypersensitivity reaction (type 4)

Question 13

What is one of the most common types of dermatitis

Answer 13

Contact allergic - response to chemicals, topical therapies, nickel, plants etc.

Question 14

What are 2 common causes of facial contact dermatitis

Answer 14

Make up or air-borne

Question 15

Why does weeping eczema occur

Answer 15

Caused by oedema between the keratinocytes

Question 16

What do Langerhans cells in the epidermis do?

Answer 16

They process the antigen

Question 17

What happens when the langerhans cell has processed the antigen

Answer 17

It is presented to the Th cells in the dermis

Question 18

What happens when the Th cells become sensitised

Answer 18

They migrate into the lymphatics and then to regional nodes where the antigen presentation is amplified

Question 19

How can specific substances causing contact dermatitis be identified?

Answer 19

Patch Testing

Question 20

What is it called when sensitised T-cells proliferate and migrate to and infiltrate the skin

Answer 20

Dermatitis

Question 21

How long after the patch testing has started are the reactions checked

Answer 21

96 hours later

Question 22

How long are the allergens left on the skin for

Answer 22

48 hours

Question 23

What type of reaction is irritant dematitis

Answer 23

Non-specific physical irritation rather than a specific allergic reaction

Question 24

What types of things can cause Irritant dermatitis

Answer 24

Soap 
Detergent
cleaning products
water
oil

Question 25

What clinical features can occur with hand dermatitis

Answer 25

``` swelling scaling erythematous increased skin markings fissuring ```

Question 26

What causes nappy rash

Answer 26

irritant contact dematitis to urine

Question 27

What percentage of school aged children are affected by atopic eczema

Answer 27

25%

Question 28

What other diseases is atopic eczema associated with

Answer 28

asthma allergic rhinitis food allergy

Question 29

What flexure is typically affected in atopic eczema

Answer 29

Flexure underneath the ear lobe

Question 30

What are the 3 chronic changes in atopic eczema

Answer 30

lichenification excoriation secondary infection

Question 31

What organism usually causes the secondary infection

Answer 31

Staph aureus

Question 32

What causes eczema herpeticum

Answer 32

Herpes simplex virus

Question 33

What can be seen in eczema herpeticum

Answer 33

monomorphic punched out lesions

Question 34

What is the treatment of eczema

Answer 34

``` plenty of emollients avoid irritants including shower gels and soaps topical steroids treat infection phototherapy - mainly UVB systemic immunosuppressants ```

Question 35

What causes atopic eczema

Answer 35

Multiple genetic and environmental factors

Question 36

What gene is most important in atopic eczema

Answer 36

filaggrin

Question 37

What can be seen in photosensitive eczema

Answer 37

Cut off at collar

Question 38

Where is a common place to see pompholyx eczema

Answer 38

Down the side of the digits

Question 39

What causes lichen simplex

Answer 39

When the patient scratches their skin often enough. Often seen on the back of the neck