• Diagnosis is based on patient's history and physical exam
• Investigate exacerbating factors
  • Eg Aeroallergens, foods, irritating chemicals, emotional stress, extreme temperature
  • Not very useful clinically
• Identify and eliminate trigger factors
  • Identify potential allergens by careful history and selective allergy tests
    • Skin prick tests and serum tests for allergen-specific IgE are only useful if there is a suspected allergen
    • Negative results are useful for ruling out suspected allergens
    • In vitro allergy tests or positive skin prick tests do not always correlate with clinical symptoms (especially foods) and controlled food challenges, atopy patch tests or elimination diets may be needed
    • Limited food allergy testing may be considered in children <5 years with moderate-severe or refractory disease and/or a history of an allergic reaction after a particular food exposure 
      • Most children will outgrow food hypersensitivity within the first few years of life
  • Avoid foods identified as allergens in controlled food challenges

Criteria for Diagnosis (Based on criteria developed by Hanifin 1991)

Major Features (must have ≥3)

• Pruritus
• Typical morphology and distribution
• Facial and extensor involvement in infants and children
• Flexural lichenification and linearity in adults
• Dermatitis - chronic or chronically relapsing
• Personal or family history of atopy - asthma, allergic rhinitis, atopic dermatitis

Minor/Less Specific Features

• Cheilitis
• Hand/foot dermatitis
• Scalp (cradle cap) dermatitis
• Ichthyosis, hyperlinearity, keratosis pilaris
• IgE reactivity (increased serum IgE, radioallergosorbent, or prick test reactivity)
• Periauricular fissures
• Eczema - perifollicular accentuation
• Cutaneous infections (Staphylococcus aureus, Herpes simplex)
• Xerosis
• Recurrent conjunctivitis
• Keratoconus
• Anterior subcapsular cataract
• Ptyriasis alba
• White dermographism

Disease Severity

• A holistic approach may be applied when assessing severity of disease

Severity	Skin	Quality of Life and Social Wellbeing
Mild	With areas of dry skin, infrequent pruritus with or without areas of redness	Minimal impact on quality of life (some disturbance during the day and during sleep, mild changes in psychosocial wellbeing)
Moderate	With areas of dry skin, frequent pruritus, redness with or without excoriation and skin thickening	Moderately affects quality of life including everyday activities and psychosocial wellbeing, sleep frequently disrupted
Severe	Extensive areas (>20%) of dry skin, intensely pruritic, erythema with or without excoriation and skin thickening; often complicated by persistent infections	Significant disruption of quality of life; sleepless nights; lost school days

• Ocular or infectious complications may also be present in severe atopic dermatitis
• May require hospitalization for severe eczema or skin infections
• Severity may also be assessed using different scoring methods [eg SCORing Atopic Dermatitis (SCORAD), Eczema Area and Severity Index (EASI), Patient Oriented Eczema Measure (POEM), Three Items Severity Score (TISS)]