Eczema: Atopic dermatitis

Question 1

Define eczema?

Answer 1

Chronic condition that causes skin itchiness, inflammation, irritation

Question 2

Why is eczema used interchangeably with the term dermatitis?

Answer 2

Eczema is a form of chronic dermatitis

Dermatitis: Conditions that cause skin inflammation

Question 3

What are the 9 main types of eczema?

Answer 3

Pompholyx
Contact dermatitis
Atopic dermatitis
Venous eczema
Lichen simplex
Gravitational eczema
Irritant dermatitis
Discoid eczema
Seborrheic dermatitis

Question 4

What is pompholyx?

Answer 4

Eczema that affects hands and feet

Question 5

What is allergic contact dermatitis?

Answer 5

Eczema caused by contact with allergen

Question 6

What is irritant contact dermatitis?

Answer 6

Eczema caused by non-specific response contact with physical or chemical irritant

Question 7

What is the most common form of eczema?

Answer 7

Atopic dermatitis

Question 8

What is the typical onset age of atopic dermatitis?

Answer 8

Childhood (before 5 yrs old) but can occur at any age

Question 9

What kind of conditions are usually associated with atopic dermatitis?

Answer 9

Other atopic conditions eg. asthma, hay fever

Question 10

What kind of history does a patient with atopic dermatitis usually present with?

Answer 10

Family history of atopy

Question 11

How does presentation of atopic dermatitis typically change with age?

Answer 11

Affects more flexural surfaces, less extensor surfaces

As age increases

Question 12

What 3 types of skin abnormalities does atopic dermatitis commonly present as?

Answer 12

Plaques

Patches

Papules

Question 13

Describe how plaques, patches or papules caused by atopic dermatitis typically present?

Answer 13

Pruritic (incessant and causes poor sleep)

Erythematous

Flaky, crusty, dry (xerosis)

Question 14

What is the typical distribution of atopic dermatitis in infants?

Answer 14

Face, scalp, neck, trunk and extensor surfaces

Question 15

What is the typical distribution of atopic dermatitis in children?

Answer 15

Flexor surfaces with residue on face, neck

Question 16

What is the typical distribution of atopic dermatitis in adults?

Answer 16

Flexor surfaces

Question 17

How is the diagnosis of atopic dermatitis confirmed?

Answer 17

Clinical diagnosis confirmed by patient history (particularly family history)

Question 18

What FBC finding can indicate atopic dermatitis?

Answer 18

Elevated eosinophil count

Question 19

What is xerosis?

Answer 19

Dry, flaky skin

Question 20

How can you investigate if eczema is causing infection?

Answer 20

Skin swab to confirm if a viral or bacterial infection has caused it, can also guide treatment

Question 21

Why can a patch test be useful in diagnosing eczema?

Answer 21

Patch test to confirm if a particular substance/allergen is causing it

Question 22

Give 2 examples of scoring tools used to measure the severity of eczema?

Answer 22

Eczema Area and Severity Index (EASI)

Dermatology Life Quality Index (DLQI)

Question 23

What types of emollients are used to treat atopic dermatitis?

Answer 23

Lotion, cream, ointments

Question 24

Which 4 topical steroids are used to treat atopic dermatitis?

Answer 24

1% hydrocortisone cream: Mildly potent so is used for infants with face, mild eczema and eyelids

Eumovate cream: Mild-moderately potent so is used for infants with body eczema, face

Elocon 0.1% cream: Moderately potent so is used for body

Dermovate cream: Very potent so is used for severe body eczema

Question 25

How does a patient measure how much topical steroid to used for eczema?

Answer 25

Finger Tip Unit (FTU): (about 500mg) is the amount needed to squeeze a line from the tip of an adult finger to the first crease of the finger Various estimates for body surface area and the number of FTUs required

Question 26

How often should a patient use topical steroid to treat eczema?

Answer 26

Daily use for 2-4 weeks then reduce to alternate days, then to 1/2 times weekly

Question 27

When are topical calcineurin inhibitors indicated for treatment of eczema?

Answer 27

Alternative to topical steroids

Question 28

How old must patients be for licensed use of topical calcineurin inhibitors, to treat eczema?

Answer 28

2 yrs old and older

Question 29

What is the most important side effect of oral calcineurin inhibitors for treatment of eczema?

Answer 29

Increase risk of lymphoma/skin malignancy

Question 30

When is phototherapy indicated for treatment of eczema?

Answer 30

Moderate-severe eczema that won’t respond to topical treatments alone

Question 31

What kind of phototherapy is used for body eczema?

Answer 31

UVB

Question 32

What kind of phototherapy is used for hands and feet eczema?

Answer 32

PUVA (psoralen and ultraviolet A)

Question 33

How often does a patient receive phototherapy to treat eczema?

Answer 33

Several appointments at hospital per week, for a few weeks

Question 34

Give 2 examples of biologics that can be used to treat eczema?

Answer 34

Monoclonal antibodies JAK inhibitors

Question 35

Can DMARDs be used to treat eczema?

Answer 35

Yes

Question 36

What are the 3 main factors that make up the pathophysiology of eczema?

Answer 36

Genetic Environmental Immunological

Question 37

What is the correlation between individuals with atopic dermatitis and infections?

Answer 37

Individuals with AD more likely to develop viral, bacterial, fungal infections

Question 38

What is the genetic factor that causes epidermal dysfunction and leads to eczema?

Answer 38

Mutation causing filaggrin deficiency (faulty epithelial differentiation genes on chromosome 1), which bind keratin in the epidermis

Question 39

Which 2 epidermal layers are most affected by eczema?

Answer 39

Stratum granulosum: Comprises keratinocytes that have matured to the point where they are beginning to produce the large amounts of keratin Stratum corneum: Contains keratinocytes that are shedding keratin

Question 40

What do epithelial differentiation genes code for, and how can mutations cause eczema?

Answer 40

Code for lipids, enzymes, proteins (eg. filaggrin) to provide stability to epidermis Unstable structure which allows penetration of allergens and microbes

Question 41

What causes dry skin in eczema?

Answer 41

Less natural moisture in skin due to reduced lipids

Question 42

What mechanical stress can contribute to eczema?

Answer 42

Itching skin

Question 43

What is the combined result of mechanical stress, unstable epidermal structure and penetration of irritants on eczema?

Answer 43

Weakens epidermal barrier more, exacerbates eczema

Question 44

What is excoriation?

Answer 44

Uncontrollable skin-picking which can cause irritation and scarring

Question 45

What is lichenification?

Answer 45

Thick leathery skin with exaggerated skin markings caused by sudden itching