Atopic dermatitis and the atopic march — clinical case

Case

A 9-month-old boy presents with a five-month history of an intensely itchy, weepy rash on his cheeks, scalp and the extensor surfaces of his arms. He scratches until the skin weeps and wakes repeatedly at night; his parents have tried over-the-counter moisturisers with little benefit. His mother has asthma and his father had childhood eczema. He is otherwise well, growing normally, and has no history of food reactions or wheeze. [1]

Findings

On examination the cheeks, scalp and extensor forearms show erythematous, excoriated, partly crusted plaques with overlying weeping in places, and the skin is generally dry (xerosis). The nappy area is conspicuously spared. There are no burrows, no annular scaly plaques, and no signs of systemic illness. He meets all five UK Working Party criteria for atopic dermatitis. The working diagnosis is moderate infantile atopic dermatitis within a strongly atopic family background. [1]

Investigations

The diagnosis is clinical, and no laboratory testing is needed to confirm it. Because there is no history of immediate food reactions, anaphylaxis or refractory disease, food-specific IgE or skin-prick testing is not indicated at this stage. A SCORAD or POEM score is recorded to grade severity and provide a baseline for treatment response. [1]

Management

He begins a generous, fragrance-free emollient applied at least twice daily and a soap-free wash as the foundation, together with a low-potency topical corticosteroid (hydrocortisone 1%) to the cheeks and scalp and a moderate-potency agent (triamcinolone) to the extensor forearms for a defined two-week course, stepped down as the flare settles. A written eczema action plan empowers the parents to step up at the first sign of a flare, and the fingertip-unit method of application is demonstrated. The parents' steroid phobia is addressed by explaining the safety of potency-matched, course-defined corticosteroid use as affirmed by the American Academy of Dermatology guidelines. [6]

Course

At two-week review the active eczema has settled substantially, the weeping has resolved, and his sleep is improved. He continues emollient maintenance with intermittent topical corticosteroid for flares. Because of his strong atopic background, the family is counselled about the atopic march — his elevated risk of food allergy, asthma and rhinitis — and advised on early introduction of allergenic solids rather than dietary restriction. A review is arranged for one month, with escalation to a topical calcineurin inhibitor or dermatology referral if control proves inadequate. [2]