Dermatitis and Eczema

Question 1

are the terms dermatitis and eczema interchangeable

Answer 1

yes

Question 2

what is the cardinal feature of eczema/dermatitis

Answer 2

itch

Question 3

what is present in the acute phase

Answer 3

papulovesicular
erythematous lesions
oedema (spongiosis)
ooze or scaling and crusting

Question 4

what is present in the chronic phase

Answer 4

thickening (lichenification)
elevated plaques
increased scaling

Question 5

is contact allergic dermatitis common

Answer 5

yes very

Question 6

what is contact allergic dermatitis typically in response to

Answer 6

chemicals, topical therapies, nickel, plants

Question 7

why does weeping occur during eczema

Answer 7

blistering and exudate is linked due to leakage of fluid across capillaries due to inflammation then leaks out of breaks in the skin

Question 8

what is the immunopathology of contact allergic dermatitis

Answer 8

langerhan’s cells in epidermis process antigen which is presented to Th cells in dermis
-sensitised Th cells migrate into lymphatic and to regional nodes where antigen presentation is amplified

Question 9

what can identify the cause of contact allergic dermatitis

Answer 9

patch testing

Question 10

how long are the wells placed on the back during patch testing

Answer 10

48 hours

Question 11

when are the reactions checked during patch testing

Answer 11

96 hours

Question 12

how common is contact irritant dermatitis

Answer 12

very common

Question 13

what is different about contact irritant dermatitis compared to contact allergic dermatitis

Answer 13

it is a non-specific physical irritation rather than a specific allergic reaction

Question 14

what are some triggers for contact irritant dermatitis

Answer 14

soap, detergent, cleaning products, water, oil

Question 15

how do you manage contact irritant dermatitis

Answer 15

history, occupation, skin history, patch testing, soap substitute, topical steroid, emollients

Question 16

what are some clinical features of contact irritant dermatitis

Answer 16

erythema, scaling, fissuring, lichenification, nail dystrophy, crusting

Question 17

atopic eczema=etopic dermatitis yes or no

Answer 17

yes

Question 18

what percentage of school children are affected by atopic eczema

Answer 18

25%

Question 19

what are some features of atopic eczema

Answer 19

pruritus, ill defined erythema and scaling, generalised dry skin, flexural distribution, other atopic diseases

Question 20

what are chronic changed associated with atopic eczema

Answer 20

lichenification, excoriation, secondary infection

Question 21

what bacteria is common in secondary infections with crusting

Answer 21

staph aureus

Question 22

what is an important infection to recognise early with atopic eczema

Answer 22

herpes simplex virus

Question 23

what does herpes simplex virus cause

Answer 23

eczema herpeticum

Question 24

what is characteristic of eczema herpeticum

Answer 24

monomorphic punched-out lesions

Question 25

what is the UK diagnostic criteria for atopic eczema

Answer 25

itching plus 3 or more of; -visible flexural rash -history of flexural rash -personal history of atopy (or first degree relative if under 4) -geberally dry skin -onset before 2 (check cheeks and extensor surfaces in infants for rash)

Question 26

what are some treatments for eczema

Answer 26

- emollients - avoid irritants - topical steroids - treat infections - phototherapy (UVB) - systemic immunosuppressants - biologics

Question 27

what causes atopic eczema

Answer 27

multiple genetic and environmental factors

Question 28

what is an important gene in atopic eczema

Answer 28

filaggrin