What are the key diagnostic criteria for atopic dermatitis in children, and how can I differentiate it from other skin conditions?

Key diagnostic criteria for atopic dermatitis (atopic eczema) in children:

• Presence of an itchy skin condition plus at least 3 of the following features:
• Visible flexural dermatitis involving skin creases such as bends of elbows or behind knees, or visible dermatitis on cheeks and/or extensor areas in children aged 18 months or under.
• Previous flexural dermatitis or dermatitis on cheeks/extensor areas in children aged 18 months or under.
• Dry skin in the last 12 months.
• Asthma or allergic rhinitis, or a history of atopic disease in a first-degree relative (for children under 4 years).
• Onset of signs and symptoms under the age of 2 years (not used as a criterion in children under 4 years).
• Note that in Asian, Black Caribbean, and Black African children, atopic eczema may affect extensor surfaces rather than flexures, and discoid or follicular patterns may be more common.

Differentiation from other skin conditions:

• Diagnosis is clinical, based on history and examination including the pattern and distribution of dermatitis and associated atopic features.
• Consider referral for specialist dermatological advice if diagnosis is uncertain or if there is poor response to treatment, suspicion of contact allergic dermatitis, or if the eczema is causing significant social or psychological problems.
• Other skin conditions may lack the characteristic flexural/extensor distribution, associated dry skin, personal or family history of atopy, or typical age of onset.

These criteria and considerations are based on NICE guideline CG57 for atopic eczema in children under 12 years ¹.