atopic dermatitis

Question 1

AD is more common in ____ (high/low) income areas possibly due to____

Answer 1

• high income - urban environments (exposure to pollutants) and lack of exposure to infectious agents may trigger development of AD

Question 2

Prevalence of AD in children? Adults?

Answer 2

• 25% in children -3% adults

Question 3

Early onset AD arises by ___ age

Answer 3

1-2 years old

Question 4

___ % of AD resolves by 12 years of age

Answer 4

60% (remember the 60’s for AD)

Question 5

Senile onset arises at ____ age

Answer 5

after 60 y/o

Question 6

___% of AD occurs within the first year of life, and ___% by 5 y/o

Answer 6

• 60% within first year - 90-95% by 5 y/o

Question 7

What is the general pathogenesis of AD?

Answer 7

interplay between: - poor epidermal barrier - immune dysregulation - environment - genetics (if child has AD, high chance one or both of parents did)

Question 8

Gene mutation associated with development of AD and severe early onset AD:

Answer 8

• Filaggrin mutation, leads to barrier dysfunction, transepidermal water loss and xerosis, allowing penetration of allergens

Question 9

Immunologic proteins and cytokines increased in AD include:

Answer 9

• Th2>Th1 - IL-4, IL-5, IL-12, IL-13

Question 10

Acute AD is ____ predominant state w/ eosinophilia and increased ____ production

Answer 10

• Th2 - IgE - remember that pregnancy is Th2 state and this is why pregnant patients can get atopic eruption of pregnancy

Question 11

Chronic atopic derm is a ____ predominant state with increased ____.

Answer 11

• Th1 - IFN-gamma

Question 12

Mediators of itch in AD are:

Answer 12

• neuropeptides - proteases - kinins - histamines (less important)

Question 13

Clinical criteria for AD are:

Answer 13

• Essential: pruritis - plus >/= 3 of the following: - history of xerosis - personal history of allergic rhinitis or asthma - onset< 2 y/o - history of skin crease involvement (antecubital, popliteal, ankle, neck, periorbital) - visible flexural dermatitis

Question 14

What will you see clinically in acute AD lesions?

Answer 14

• erythema, edema, vesicles, oozing and crusting

Question 15

What will you see clinically in subacute/chronic AD lesions?

Answer 15

• lichenification, papules, nodules, and excoriations

Question 16

Pediatric/infantile AD occurs from ___ to ___ age

Answer 16

• birth to 6 months

Question 17

Pediatric/infantile AD favors which body parts?

Answer 17

• face, scalp, EXTENSOR surfaces

Question 18

Childhood AD occurs from ___ to ____ age

Answer 18

• 2 years to puberty

Question 19

Childhood AD favors ____ areas of body

Answer 19

• flexural (infantile favors extensors, face, scalp)

Question 20

Diffuse xerosis in AD patients tends to become more prominent in which age group?

Answer 20

• childhood (2 y/o to puberty)

Question 21

Adolescent/Adult AD starts at age ____

Answer 21

• 12

Question 22

clinical findings of adolescent/adult AD?

Answer 22

• lichenified plaques > weeping eczematous lesions

Question 23

Adolescent/adult AD favors which body parts?

Answer 23

• flexures, face, neck, upper arms, back and acral sites - adults tend to have more hand involvment

Question 24

AD beginning during childhood is associated with ___ (more/less) severe disease as adults

Answer 24

• more severe, treatment-resistant disease

Question 25

Senile AD presents as:

Answer 25

- marked xerosis rather than typical AD lesions

Question 26

Name the associated features of AD:

Answer 26

- xerosis - ichthyosis vulgaris - Keratosis Pilaris - palmoplantar hyperlinearity - Dennie-Morgan lines (underneath eyelid from medial canthus) - allergic shiners - white dermatographism - diminished lateral eyebrows - circumoral pallor - anterior neck folds

Question 27

Children, especially those with darker skin types, have increased incidence of \_\_\_\_\_, which is more visible after \_\_\_\_

Answer 27

- pityriasis alba - more visible after sun exposure

Question 28

Bacterial impetiginization is most often with ____ \> \_\_\_\_\_

Answer 28

- S. aureus \> S. pyogenes

Question 29

Viral complications that can occur secondary to disrupted barrier in AD include:

Answer 29

- eczema herpeticum (usually HSV1 or 2) - molluscum dermatitis - eczema vaccinatum (Seen with smallpox vaccination)

Question 30

Ocular complications of AD are:

Answer 30

- atopic keratoconjunctivitis - vernal keratoconjunctivitis (children in warmer climates) - posterior subcapsular cataracts - keratoconus (elongation of cornea) - retinal detachment

Question 31

\_\_\_\_\_ occurs in spring/summer in boys on elbows/knees and appears as clusters of small 1-2mm lichenoid papules

Answer 31

- frictional lichenoid eruption (regional variant of AD)

Question 32

Dyshidrotic eczema occurs on _____ parts of body and is described clinically as\_\_\_\_

Answer 32

- lateral fingers and palms - "tapioca-like" firm and deep-seated pruritic vesicles

Question 33

Histopath of acute AD:

Answer 33

- prominent spongiosis!! - intraepidermal vesicles/bullae - perivascular lymphohistiocytic inflammation with eosinophils

Question 34

Histopath of subacute AD

Answer 34

- milder spongiosis vs acute. - increased acanthosis!! - lacks vesicles/bullae of acute AD

Question 35

Histopath of chronic AD

Answer 35

- marked irregular to psoriasiform acanthosis!! (Key feature - minimal to no spongiosis - +/- dermal fibrosis and hyperkeratosis

Question 36

In some patients, identifications of allergens using which tests can be of use?

Answer 36

- Fluorescence enzyme immunoassays - RAST testing - Skin prick testing - atopy patch testing

Question 37

When can you consider testing for food allergies for AD?

Answer 37

- severe/refractory AD, or if worsening dermatitis after an ingestion

Question 38

What percent of AD patients have coexisting food allergy?

Answer 38

- 10-15%

Question 39

Common exacerbating factors of AD:

Answer 39

FADS - fragrances, fabrics, food allergies -other Allergens (pet dander, dust mites) - Dry environments, Detergents - Smoking, Sweating, Showers to hot, too long, too often, stress

Question 40

60% rule for AD:

Answer 40

- 60% have onset within first year of life, 60% resolve by age 12.

Question 41

3 clinical features critical for diagnosis of AD:

Answer 41

1. Pruritis 2. chronic relapsing and remitting course 3. eczematous rash

Question 42

RAST testing detects:

Answer 42

- antigen specific IgE in blood

Question 43

Skin prick/patch testing works by:

Answer 43

- detecting allergen specific IgE that activates mast cells and leaves pt with contact dermatitis or wheal.

Question 44

What is general trend on histopathology as you move from acute to chronic AD?

Answer 44

- acute has more spongiosis, less acanthosis - the more chronic, the less spongiosis and more acanthosis you will get.

Question 45

How to educate for AD patients?

Answer 45

- use emollients - short lukewarm baths with minimal soap - can do bleach baths (especially if history of infections) - wet dressings +/- topical steroids - avoid irritants (And common FADS triggers)

Question 46

Mainstay of tx for AD is:

Answer 46

- topical corticosteroids

Question 47

Child is having itch and it is keeping him up at night, what medication can you add

Answer 47

- sedative antihistamine

Question 48

treatment ladder for AD

Answer 48

topicals (steroids, calcineruin inhibitors), light therapy , systemic meds (systemic corticosteroids, cyclosporine, azathioprine, MMF, MTX)

Question 49

Primary prevention of AD is via ____ after birth

Answer 49

Breast feeding or formulas w/ hydrolyzed milk products for first 4-6 months

Question 50

What other supplementation can be used prenatally and postnatally to reduce risk of atopic dermatitis?

Answer 50

- probiotics

Question 51

Prognosis of AD:

Answer 51

Tends to clear by puberty in most children - 60% cleared by age 12