Eczema

Question 1

What are the features of atopic dermatitis?

Answer 1

• Chronic, relapsing skin disorder (chronic disease with recurrent flares)
• Dry skin
• Red, inflamed scaly rash
• Intense pruritus (itch)

Question 2

What is atopic dermatitis usually associated with?

Answer 2

Personal or family history of atopic disease e.g. asthma, allergic rhinitis, atopic dermatitis

Question 3

What is the atopic march?

Answer 3

The progression of allergic conditions that occur incl. atopic dermatitis, food allergy, asthma and allergic rhinitis (atopic dermatitis is usually one of the first things to manifest in patients with atopy)

Question 4

What are the diagnostic criteria for atopic eczema?

Answer 4

Must have an itchy skin condition in the last 12 months and 3 or more of:

1) Onset below age 2
2) History of flexural involvement
3) History of generally dry skin
4) Personal history of other atopic disease (or in first degree relative if < 4)
5) Visible flexural dermatitis

Question 5

When does atopic dermatitis present?

Answer 5

• Mostly first year of life and between 1-5
• Rarely first time in adulthood
• 20% of children, 2-3% of adults (most people grow out of it)

Question 6

What % of patients with atopic dermatitis eventually develop allergic rhinitis or asthma?

Answer 6

50%

Question 7

What are environmental factors that cause atopic dermatitis?

Answer 7

1) Allergens
2) Irritants
3) Dietary factors
4) Infections
5) Pollutants
6) Stress
7) Weather change

Question 8

What are the immunological causes of atopic dermatitis?

Answer 8

1) Abnormal Th2 immune response

2) IgE

Question 9

What are genetic causes of atopic dermatitis?

Answer 9

1) Family history
2) Gene predisposition
3) Defective skin barrier

Question 10

What does filaggrin do?

Answer 10

Filaggrin is a protein within skin that helps bind together the top layer of skin (keratinocytes), keeping moisture inside skin and preventing antigens getting inside the skin

Question 11

Describe barrier dysfunction in eczema

Answer 11

• 40% of people who carry the filaggrin mutation develop eczema
• Filaggrin gene mutation causes barrier dysfunction which allows antigen to enter the skin, causing an inflammatory Th2 immune response
• These patients are also more likely to have other atopy
• More likely to have mutation if have significant increased hyperlinearity of palms

Question 12

How does eczema present in infants?

Answer 12

Classically head and neck affected (and other areas esp. flexural areas)

Question 13

What is eczema often confused with in infants and how is it different?

Answer 13

• Seborrheic dermatitis = overgrowth of malassezia yeasts on skin, which is also v common in babies
• Eczema is often a lot more itchy

Question 14

How does eczema present in children?

Answer 14

• Flexural sites of skin - antecubital and popliteal fossae

- Around neck and skin creases

Question 15

How does eczema present in adults?

Answer 15

• Hand dermatitis
• Antecubital and popliteal fossae
• Back of neck

Question 16

How is the rash in eczema different from the one in psoriasis?

Answer 16

It is not as clearly demarcated

Question 17

What are clinical features of eczema present in certain patients?

Answer 17

1) Lichenification
2) Periorbital eczema Dennie Morgan fold
3) Xerosis
4) Excoriations
5) Prurigo

Question 18

Describe lichenification

Answer 18

• Increase skin marking (thickening)
• Brought about by chronic eczema (not acute)
• Develops over a period of time and is made worse by rubbing the skin persistently

Question 19

Describe periorbital eczema

Answer 19

Eczema can occur around the eyes and can be made worse by allergic conjunctivitis

Question 20

What are Dennie Morgan folds?

Answer 20

Pronounced infraorbital folds around the eye that are a classical feature of eczema

Question 21

Describe xerosis

Answer 21

• Very dry skin all over without active eczema

- Need to moisturise skin to correct the epidermal dysfunction

Question 22

What are excoriations?

Answer 22

• Marks from scratching due to itchy skin

- Many patients will scratch until they bleed - gives relief but not good

Question 23

What is (nodular) prurigo?

Answer 23

• Marks from scratching skin

- Thickened areas on the skin with eroded tops

Question 24

What happens with infections in eczema?

Answer 24

• May present with yellowy, honeycomb-like, serous dried crust over eczema
• Can be weepy and increasingly score
• Can be difficult to see if it is infected

Question 25

Why are infections more common in eczema than psoriasis?

Answer 25

In part due to increase barrier dysfunction

Question 26

What types of infections can happen in eczema?

Answer 26

- Skin infections - Higher rate of colonisation with S.aureus - HSV

Question 27

What happens to eczema in adulthood?

Answer 27

- Most children outgrow the disease | - But as adults they may continue to have localised problems with dermatitis esp. hand dermatitis

Question 28

What complications can HSV lead to in eczema?

Answer 28

- Eczema herpeticum (red dots on face) - Patient has lots of small cuts on the skin which means that infections like HSV can easily get in - Sometimes can also see vesicles on the skin - Can be serious bc can cause corneal ulceration if the cornea is affected which needs to be treated quickly with IV aciclovir

Question 29

Why and how is the amount of S.aureus tried to be reduced on the skin of eczema patients?

Answer 29

- Bc S.aureus on the skin can lead to repeated episodes of infection and worsening of their eczema - Antimicrobial washes or bleach baths

Question 30

What are co-morbidities that occur with eczema?

Answer 30

- Atopic co-morbidities - Allergic contact dermatitis - Infection - Autoimmune disease - Skin pain - Sleep disturbance - Neuropsychiatric problems - Cardio-metabolic issues

Question 31

What are key problems about living with eczema?

Answer 31

- Itch - Sleep - Social interactions - Control

Question 32

What topical treatments are used to treat eczema?

Answer 32

1) Moisturisers/emollients 2) Topical steroids - no rebound problem, but still want to be cautious so instruct patients how much and how to use 3) Calcineurin inhibitors - young children, face, around eyes, safe alternative or to wean steroids, can burn at first but wears off 4) Antiseptic washes 5) Wet dressings - wet wraps to alleviate symptoms

Question 33

What medications are used to treat eczema?

Answer 33

1) Intermittent courses of oral steroids (v effective) 2) Phototherapy - some can be photo-aggravated so only use in patients whose eczema gets better in sun (difficult to tell bc often heat makes it worse so don't know if it is sun or heat and sweat) 3) Methotrexate 4) Cyclosporin - brings immune system down to normal, not immune suppression 5) Dupilumab (v effective for some patients)

Question 34

What type of biologic is used in eczema?

Answer 34

Dupilumab (IL-4 and IL-13 inhibitor)

Question 35

What do IL-4 and IL-13 do?

Answer 35

1) IL-4 recruits Th2 cells in the skin | 2) IL-13 recruits eosinophils and IgE within the skin

Question 36

How is use of biologics different in eczema from psoriasis?

Answer 36

Can be used much more freely in eczema - only had to try one systemic therapy and no specifics about disease severity just severe

Question 37

What score is used to measure severity of eczema?

Answer 37

EASI

Question 38

What are potential side effects of dupilumab?

Answer 38

- Conjunctivitis - Enthesitis - Arthritis