Contact Dermatitis

Question 1

def

Answer 1

allergic or irritant skin reaction due to an external agent

Question 2

epi

Answer 2

very common

Question 3

who is more likely to be sensitive to nickel

Answer 3

women (jewellery)

Question 4

who is more likely to be sensitive to chromate

Answer 4

men (occupational exposure)

Question 5

what are 3 common causes of allergic contact dermatitis

Answer 5

1 nickel sulfate
2 neomycin
3 myroxylon pereirae

Question 6

what is neomycin

Answer 6

a topical aminoglycoside antibiotic

Question 7

what is myroxylon pereirae

Answer 7

AKA as balsam of peru

used in food, drink, perfumes, toiletries for flavouring and fragrance

Question 8

what are 2 common causes of allergic contact dermatitis in children

Answer 8

1 nickel sulfate

2 gold sodium thiosulfate

Question 9

what is gold sodium thiosulfate found in

Answer 9

gold jewellery

Question 10

what are the two forms of contact dermatitis

Answer 10

allergic contact dermatitis

irritant contact dermatitis

Question 11

what causes irritant contact dermatitis

Answer 11

chronic cumulative ICD by water, soaps, solvents

Question 12

aetiology of irritant contact dermatitis

Answer 12

direct toxicity without prior sensitization

Question 13

aetiology of allergic contact dermatitis

Answer 13

delayed hypersensitivity reaction with prior sensitization

Question 14

risk factors

Answer 14

occupation with frequent exposure to water or irritants

atopic dermatitis

Question 15

how does frequent water cause ICD

Answer 15

a compromised epidermal barrier allows easier penetration of irritants and allergens

Question 16

what is phototoxic dermatitis

Answer 16

allergen or irritant is activated by sunlight

Question 17

history

Answer 17

common to present with occupational Hx of frequent water exposure +/ history of atopic dermatitis
acute onset of (ICD is minutes, ACD is hours) of itchy, red skin which affects hands and face

Question 18

what symptoms is someone with ICD more likely to present with

Answer 18

burning and stinging skin

Question 19

what symptoms is someone with ACD more likely to present with

Answer 19

vesicles and bullae (fluid filled sacs on skin)

Question 20

which hand may be more affected in ICD

Answer 20

the dominant hand

Question 21

investigations

Answer 21

1 patch testing is gold standard (specific and sensitive)
2 skin biopsy (patch testing)
ICD - variable
ACD - spongiosis, vesiculation, epidermal hyperplasia in chronic ACD

Question 22

what is spongiosis

Answer 22

intracellular oedema