【正文】 F:M=:1 – On the rise, ? 210 fold over last 30 yrs – Significant higher chance with familiar atopic history ? Interaction of environmental and geic factors – Degree of urbanization – Hygiene theory: infection and atopy Pathogenesis ? Geics – Skin barrier – Dysregulation of immune responses ? Barrierdisrupted skin: – Impaired barrier function* *Target for treatment ? Ceramidewater holding, ceramidase ↓ ? Sphingomyelin deacylase ↓ ? Filaggrin – Clinical features ?the itch that rashes? ? Severe dryness, irritated, itchy, secondary infection Immunological Reactions ? Th2 dominance in acute phase – Cytokine ? IL4 and IL5 ? IL10 – IgE, eosinophil ? Th1 dominance in chronic phase – IFN? producing T cells ? Langerhans cell Infantile AD ? 60% of AD present in the first year of life, 2m2yr ? Sites most affected – Cheeks, then spread to neck, forehead, wrists, and extensor extremities ? Eruption: acute and moist in feature – Erythematous patches, vesicles, exudate, crust, pustules ?奶癬 , fungal infection due to milk? ? Causes – Food allergy ? egg, milk, chicken, fish ? peanut, wheat, soy ? Maternal ingest of allergen – Inherited skin barrier dysfunction Adolescent and Adult AD ? Eruption – Adolescents ? Similar to childhood AD – Older adults ? Localized plagues, erythematous, scaly or papular, lichenified, and scaly ? Sites less characteristic ? Dry skin, itchy ? Emotional stress, depression, anxiety, and exercise can be the trigger ? Improvement occurs, and AD resolves before middle life Diagnosis Criteria for Diagnosis 1. Williams: Pruitus plus 3/5 items 2. AAD 3. UK working Party?s Diagnostic Criteria for AD ? Major criteria: three of these – Pruritus – Typical morphology and distribution – lichenification in adults – Facial and extensor involvement in infancy – Chronic or chronically relapsing dermatitis – Personal or family history of atopic disease UK working Party?s Diagnostic Criteria for AD ? Minor criteria: three of these ? Xerosis ? Ichthyosis ? IgE reactivity ? Elevated serum IgE ? Early age of onset ? Tendency for cutaneous infections ? Tendency to nonspecific hand/food dermatitis ? Nipple eczema ? Cheilitis ? Recurrent conjunctivitis ? DennieMan infraorbital fold ? Keratoconus ? Anterior subcapsular cataracts ? Orbital darkening ? Facial pallor/facial erythema ? Pityriasis alba ? Itch when sweating ? Intolerance to wool and lipid solvents ? Perifollicular accentuation ? Food hypersensitivity ? Course influenced by environmental and/or emotional factors ? White dermographism or delayed blanch to cholinergic agents Differential Diagnosis ? Dermatoses – Seborrheic dermatitis – Allergic contact dermatitis – Nummular dermatitis – Scabies – Psoriasis ? Immunodeficiency syndrome in infants Management of AD: General ? Infancy and Childhood – Avoid external irritation, scratching, soap, hot shower, food allergens – Antihistamine with sedative effect ? Adults – Avoid cold and heat, overbathing, hot shower, soap, wearing wool, emotional stress – Use moisturizers to get skin hydrated – Tackle the itch: ice cubes Management of AD: specific therapies 1 ? Topical – Hydration: 10%urea cream, Cod liver ointment – Stages of lesion ? Oozing: 3% boric acid solution, potassium permanganate solution ? Subacute: Zinc Oxide oil, Calamine lotion – Corticosteroid cream – Calcineurin inhibitors cream ? Systemic – Antihistamines, ? Immune modulator – Cyclosporine, IVIg Management of AD: specific therapies 2 ? Phototherapy – PUVA, UVB, UVA ? Immune suppressive ? Langerhans cells ? ? IL10??NK? and T cells? ? Apoptosis of T cells? ? HeNe Laser ? Freezing Eczema ? Greek word, ekzein, meaning “boil out” or “effervesce” ? A morphologic category ? Loosely defined as a group of diseases with epidermal changes of scale, parakeratosis and spon