Summary

Atopic Eczema (Atopic Dermatitis) is a chronic, relapsing, inflammatory skin condition characterised by dry skin and intense pruritus ("The itch that rashes"). It affects 20% of children and 5-10% of adults. It is part of the "Atopic Triad" (Eczema, Asthma, Hayfever). The core defect is a breakdown of the skin barrier (Filaggrin mutation), allowing water loss and allergen/microbe entry. Management involves repairing the barrier with copious Emollients and suppressing inflammation with Topical Steroids during flares. The most dangerous complication is Eczema Herpeticum (HSV superinfection), which is an emergency requiring systemic Acyclovir.

Key Facts

• Prevalence: 1 in 5 children.
• Genetics: Loss of function mutation in Filaggrin gene.
• Distribution:
  • Infants: Face and Extensors.
  • Children/Adults: Flexures (Antecubital / Popliteal fossae).
• Emergency: Eczema Herpeticum (Punched out monomorphic erosions).
• Steroid Rule: Use the weakest effective dose for the shortest time, but do not undertreat. Use Finger Tip Units (FTU).

Clinical Pearls

"Grease is Good": Ointments (greasy) are far superior to creams (water-based) for barrier repair. They contain fewer preservatives (which can sting) and trap moisture better. Patients hate the grease, but the skin loves it.

"The Itch-Scratch Cycle": Reviewing a child with bloody fingernails? The scratching damages the barrier further, releasing cytokines, causing more itch. You must break the cycle with potent treatment (Steroids + Antihistamines for sedation at night).

"Infected?": If the eczema is weeping golden crusts, it is Staphylococcus aureus. If it is painful punched-out holes, it is Eczema Herpeticum.

"Soap is the Enemy": Normal soap strips the natural oils (sebum) from the skin. Patients must use a soap substitute (dermol, aqueous cream) to wash.

          PATIENT WITH ATOPIC ECZEMA
                     ↓
        ASSESS SEVERITY (Impact on Life)
                     ↓
      ┌──────────────┼───────────────┐
     MILD         MODERATE        SEVERE
  (Dry skin,      (Redness,      (Lichenified,
   Low itch)       Itch)          Weeping)
      ↓              ↓               ↓
  EMOLLIENTS      EMOLLIENTS      EMOLLIENTS
  (Liberally)     + STEROID       + POTENT STEROID
                  (Mild/Mod)      (Mod/Potent)
                                  + BANDAGING?

1. General Measures

• Avoid Irritants: Soap, wool, biological detergents.
• Deterrence: Keep nails short to minimize damage from scratching.

2. Emollients (The Base)

• Apply liberally and frequently (min 250g/week).
• Apply in direction of hair growth (to avoid folliculitis).
• Use as soap substitute.
• Ladder: Lotion (Light) -> Cream (Med) -> Gel -> Ointment (Heavy/Greasy). Ointments best (e.g. 50:50 WSP/Paraffin).

3. Topical Steroids (The Fire Engine)

• Use to extinguish the flare.
• Regimen: Once daily for 1-2 weeks until skin feels normal, then step down.
• Potency:
  • Mild: Hydrocortisone 1% (Face/Neck).
  • Moderate: Eumovate (Clobetasone).
  • Potent: Betnovate (Betamethasone).
  • Very Potent: Dermovate (Clobetasol) - Specialist only.

4. Second Line

• Calcineurin Inhibitors: Tacrolimus (Protopic) / Pimecrolimus (Elidel).
  • Use: Sparing effect (Face/Eyelids) where steroids cause thinning.
  • Side effect: Stinging.

5. Severe / Resistant

• Bandaging: Wet Wraps (Paste bandages) to cool skin and increase absorption.
• Phototherapy: UVB.
• Systemic: Methotrexate, Cyclosporine, Dupilumab (Biologic against IL-4/13).

How much steroid to apply? 1 FTU = Line of cream from DIP joint to tip of index finger (~0.5g).

Memorise one from each class.

Note: Use ointment formulations for dry eczema, cream for wet eczema.

NICE CG57 (Atopic Eczema in under 12s)

• Stepped approach dictated by severity.
• Offer choice of emollients (let child choose texture).
• Refer if: infected, severe sleep disturbance, psychosocial impact.

Cochrane Reviews

• Wet Wraps: Effective for severe eczema but labour intensive.
• Probiotics: No clear evidence for prevention.
• Diet: Elimination diets usually NOT recommended unless clear food allergy link (urticaria/vomiting immediately after eating).

What is Eczema?

It is a condition where your skin's "brick wall" is leaky. Most people have a strong wall that keeps water in and germs out. In eczema, the mortar between the bricks is missing (due to genetics). Water escapes (dryness) and soap/pollen gets in (irritation).

Will they grow out of it?

Most likely. About 60-70% of children improve significantly by their teenage years, although they may always have dry skin.

Are steroids safe?

Yes, if used correctly. Many parents are "steroid phobic" and undertreat, leaving the child in misery. Thinning of the skin only happens if you use very strong steroids for months without a break. Using them for 1-2 weeks to clear a flare is perfectly safe and necessary.

How often should I moisturise?

"Until the pot is empty, then buy another." You cannot overdose on moisturiser. Ideally 3-4 times a day.