Eczema

Question 1

what is the basic pathophysiology of eczema?

Answer 1

barrier dysfunction + inflammation

Question 2

where is eczema more common in?

Answer 2

cooler climates
more pollution
more so in developed regions - perhalps due to aseptic environments or household cleaning products ?

Question 3

what gene plays a key role in eczema?

Answer 3

fliggarin gene

Question 4

what is the pathology of eczema?

Answer 4

spongiosis (oedema iwhtin epidermis)
acanthuses (thickening of epidermis)
inflammation with superficial perivascular lymphohistiocytic infiltrate

Question 5

what is the distribution of eczema?

Answer 5

flexural
neck, eyelids, face, hands, feet
tends to spare the nappy area due to the area being humid (eczema favours cooler climates)

Question 6

what are features of chronic changes of eczema?

Answer 6

lichenification
plaques
fissuring

Question 7

what type of reaction is allergic contact dermatitis? and how long does it take to occur?

Answer 7

type 4 hypersensitivity

24-72 hours to develop a rash/reaction

Question 8

what cell type is allergic contact dermatitis triggered by?

Answer 8

T cell mediated type 4 hypersensitivity reaction

Question 9

what causes irritant contact dermatitis?

Answer 9

injury to the skin due to friction i.e. micro trauma or cumulative
environmental factors i.e.;
- cold
- over exposure to water
- chemicals i.e. acids, alkalis, solvents, detergents

occupation
nappy rash
webs of finger due to not drying hands properly

Question 10

how would you investigate irritant or allergic contact dermatitis?

Answer 10

patch test to identify allergen / trigger

Question 11

what is the distribution of seborrheic dermatitis?

Answer 11

scalp and proximal flexures

scaling particularly around scalp, eyebrows and ears

Question 12

what is the cause of seborrheic dermatitis?

Answer 12

malassezia yeast (mites)

Question 13

what is the treatment for seborrheic dermatitis?

Answer 13

anti - yeast

ketoconazole

Question 14

what is the presentation of seborrheic dermatitis in adults?

Answer 14

red, sharply marinated lesions covered with greasy looking scales
occur in areas rich in sebaceous glands i.e. scalp, face and upper trunk

Question 15

what is the presentation of discoid eczema?

Answer 15

circular plaques of eczema
sometimes large patches / plaques
may develop at site of trauma / irritation

Question 16

what age do you normally find discoed eczema?

Answer 16

adults

often occurs in people who had eczema as a child then went away and has re occurred as discoid after stress etc

Question 17

what is the presentation of pompholyx / vesicular eczema?

Answer 17

itchy vesicles, very swollen and inflamed
these vesicles often burst 
very painful 
intensely itchy 
occurs in the palms and soles

Question 18

in what age if pompholyx / vesicular eczema most common ?

Answer 18

40s

Question 19

what type of eczema is characterised by sudden onset of crops of vesicles which are very painful / itchy ?

Answer 19

pompholyx / vesicular eczema

Question 20

what type of eczema would typically present due to an old lady sitting at the fire place ?

Answer 20

asteatotic eczema

• occurs in ageing population as their skin starts to dry out
• heat triggers it
• most commonly affects shins , lower legs

Question 21

what is the presentation of venous eczema ?

Answer 21

there is increased venous pressure
oedema
occurs in ankles, lower legs
brown staining of skin

Question 22

what organism is responsible for eczema herpeticum?

Answer 22

herpes simplex 1 and 2

Question 23

what is the presentation of eczema herpeticum?

Answer 23

monomorphic pattern of lesions which burst and crust
fever and often unwell
itchy cluster of blisters and erosions
swollen lymph nodes

Question 24

what is the treatment for eczema herpeticum?

Answer 24

anti virals

Question 25

what are the treatments for eczema?

Answer 25

treating barrier:
topical emollients; ointments, creams & lotions
treating inflammation:
topical steroids
severe eczema:
ultraviolet light (UVB)
immunosuppression i.e. azathioprine, methotrexate , cyclosporin etc

Question 26

What test would you carry out for a type 1 hypersensitivity reaction?

Answer 26

Skin prick test

Question 27

What test would you carry out to determine cause of a type 4 hypersensitivity reaction?

Answer 27

Patch test

Question 28

What cell types are involved in a type 1 and type 4 hypersensitivity reaction?

Answer 28

Type 1 = mast cells

Type 4 = T cells

Question 29

If someone presents with hand dermatitis, what signs would you suspect to find on her nails?

Answer 29

Onycholysis
Acute paronchyia
Ridging of the nails