Atopic eczema (atopic dermatitis)

1. Chronic inflammatory itchy skin condition
2. Usually develops in early childhood (2–6mo)
3. 80% will grow out of it in early childhood otherwise follows a remitting & relapsing course
4. Has genetic & environmental components
5. Leads to the breakdown of the skin barrier
6. The skin is susceptible to trigger factors, including irritants, infections, allergens, and food intolerances which can exacerbate the condition
7. It can have a significant impact on quality of life

Diagnosis

Eczematous eruptions

1. Inflamed papules and plaques
2. May be dry, often assoc with pruritus and serous discharge
3. Type of eczema is a clinical diagnosis (histological features similar)

Atopic eczema

1. Itchy dry skin condition with 3 from:
   1. Visible/History of flexural dermatitis involving skin creases (or face/neck/extensor areas if <18mo, nappy area spared)
   2. Dry skin in last 12 months
   3. Personal/First-degree relative childhood history of other atopic conditions
2. If >4ys old, then onset of signs/symptoms was under age of 2yr
3. In Asian/Afro-Caribbean groups, may affect extensor > flexures, and more likely to be discoid or follicular

Triggers / Risk Factors

1. Irritants
   1. Wool, soap, sweat, detergents, sand, chlorine, many chemicals, heat
   2. Latex, perfumes, metals, preservatives
   3. Food intolerance (Non-IgE) – perioral irritation (salicylates, colourings &/or preservatives) ± nappy rash.
2. Allergens
   1. Airborne: House dust mite (nocturnal itch , progressively periorbital-forehead-facial-neck-flexures-whole body), animal dander, pollen, etc.
   2. Food allergens (1–2y): eggs, nuts, cow’s milk, soya, fish, wheat, etc.
3. Infection – see later
4. Climate
   1. Extremes of temperature & low humidity, changes in weather
5. Environmental factors
   1. Hard water, pollution, smoking
6. Genetics
   1. 25% have a filaggrin mutation
7. Higher socioeconomic group
8. Stresses
   1. if run down, viral infection, immunization

Assessment

Scoring systems

1. E.g. SCORAD, based on:
   1. Age
      1. Below or above 20 months
   2. % Spread over front/back of:
      1. Face, Upper Limbs, Trunk, Lower Limbs
   3. Intensity:
      1. Erythema, oedema, oozing, excoriation lichenification, xerosis
   4. Subjective signs:
      1. Pruritus & insomnia

Management

1. ECEMA review:
   1. E: existing diagnosis correct?
   2. C: co-existent disease process?
   3. E: environmental factors accounted for?
   4. M: medication adequate?
   5. A: allergy and/or intolerance involved?
2. Stepped approach of increasing therapy to avoid precipitant & reduce inflammation.

Emollients

1. Use unperfumed & liberally >3 times a day (unless very humid – automoisturisation)
2. A number to choose from so depends somewhat on preference
3. Suggest: Dermeze or Eucerin or QV Intensive AND QV Bath Oil or Oilatum in bath
4. Moisturise in direction of hair follicle
5. Avoid sorbolene because of propylene glycol
6. Avoid zinc with castor oil – contains peanut oil (potential for sensitization)

Topical steroids

1. Use 2wk cycles: max 10d on steroids then 4d steroid free, then repeat if needed.
2. Ointments better but messier than creams
3. Flexures: Hydrozole bd-qid may be useful

Potency	Generic	Frequency	Brand
Mild (for face, ears, closed flexures)	Hydrocortisone acetate 0.5%	bd-qid	DermAid
	Hydrocortisone acetate 1%	bd-qid	Sigmacort
Moderately potent	Betamethasone valerate 0.02%	bd	Celestone
	Triamcinolone acetonide 0.02%	bd	Aristocort
Potent	Betamethasone dipropionate 0.05%	bd	Diprosone or Eleuphrat
	Methylprednisolone aceponate 0.1%	od	Advantan
	Mometasone furoate 0.1%	od	Elocon

Topical Calcineurin Inhibitors

1. Immunomodulators
2. Used if eczema not controlled by or unable to use topical steroids
3. Tacrolimus
   1. $70 to $90 for face for a few months
   2. Good for facial or eyelid dermatitis
   3. 0.01% ointment use bd
4. Pimecrolimus(Elidel)
   1. More expensive
   2. Not as effective
   3. Theoretical risk of skin cancer and lymphoma
   4. No blood levels required
   5. Safe for a few years on and off (a few weeks at a time)
   6. Generally not used in under 2 yr olds or under dressings

Wet Dressings

1. Advantages:
   1. Cools skin, keeps hydrated, prevents scratching, improves penetration of ointments
2. At home: two hour application:
   1. After two hours dries out and benefit lost
   2. Many won’t tolerate overnight
   3. Try after dinner for an hour
3. In hospital:
   1. Leave on continuously, change tds, rewet if dry out
4. Instructions:
   1. Cotton PJ’s one size too small
   2. Damp with warm water
   3. Steroid then emollient
   4. PJ’s on, with dry pair over top or tubifast or gauze or dressing gown (wash daily!)
   5. In babies use soft cotton bonds suits with long legs (with feet cut off)

Adjuncts: Antihistamines

1. Not routinely prescribed
2. Usually not licenced for under 2yrs
3. Trial non-sedating antihistamine for 1mo if severe pruritus, e.g. cetirizine, loratidine
4. Short course of sedating antihistamine in age>6mo if sleep disturbance
5. Use phenothiazines and titrate to effect, e.g. Phenergan, Vallergan, Vallergan forte

Phototherapy & Systemic Therapy

1. Consider for severe symptoms when
   1. Other management options fail
   2. Significant impact on quality of life
2. Needs specialist paediatric dermatological supervision

Phototherapy

1. Consider for age > 9yrs
2. Ultraviolet light (UVA or UVB) under controlled conditions.
3. PUVA = Psoralen, a photoactive drug, with UVA
4. Mechanism incompletely understood
   1. ?Immunosuppression
5. Adverse effects reported include
   1. Erythema, burning, blistering, dryness, freckling
6. Skin cancer risk negligible with 1 course of phototherapy

Systemic therapy

1. Try elimination diet before considering systemics
2. Some evidence for the effectiveness of:
   1. Cyclosporin: start at 3 – 5 mg/kg/day and wean quickly
   2. Systemic corticosteroids: betameclasone, methylprednisone & prednisolone used
   3. Azathioprine: start at 1mg/kg/day
   4. Interferon gamma
   5. IV Ig monthly for 3 months
3. Other: methotrexate, mycophenolate mofetil or tacrolimus in children

Secondary Skin Infections

Staphylococcus aureus

1. Superficial infection – most common
2. Pustules, purulent exudation, erythema
3. Occasionally toxic shock/scalded skin syndromes
4. If eczema improves after course of antibiotics, consider giving for 3 months
5. Antibiotics: cephalexin, flucloxacillin or Bactrim
6. For Staph colonisation:
   1. Regular QV Flare up bath oil (young infants) or bleach baths
   2. Daily prophylactic Bactrim
   3. Nasal ?Bactroban for carriage by patient/family

Streptococcus pyogenes

1. Deeper infection
2. Glazed erythema in flexures
3. Less common
4. ABx similar to S. Aureus

Herpes simplex

1. Eczema herpeticum
2. Punched out haemorrhagic appearance, scalloped edge, persistent
3. Swab and send for PCR
4. Acyclovir

Varicella zoster

Molluscum contagiosum

1. Typically get surrounding eczema
2. Spread via warm water e.g. 34°C (typically swimming lessons)
3. Stop swimming
4. Shower standing up i.e. no pool forms around buttocks
5. Avoid rough towelling
6. Best treatment is to express hard core from centre after EMLA (only if over 6yrs)
7. Imiquimod 5% – 3x / week, or mixed with aq cream daily

Verrucae vulgaris (viral warts)

Role of food allergy

1. If eczema severe:
   1. Do skin prick testing early
   2. If breastfeeding Mum needs to avoid allergens as well
2. Unclear if true increase in allergy or if just increased recognition
3. Commonest culprits: dairy, seafood, nuts esp. peanuts
4. Can do yearly skin prick test to see if reducing reaction (better than RAST)
5. Beware false positives – go with clinical
6. Size of reaction not correlated with risk of anaphylaxis

When to refer to dermatologist

1. Severe eczema not controlled with strong topical steroids
2. Requires non-steroid topical treatment e.g. tacrolimus
3. Long term repeated infections
4. Admission for wet dressings required
5. Systemic immunosuppressives required