【正文】 324:1376–9 0 5 10 15 年齡 (歲 ) 特應(yīng)性皮炎 AD(濕疹 ) 食物過敏 哮喘 鼻炎 Key Features ? Chronic, relapsing dermatitis associated with intense pruritus ? Three stages: infantile, childhood and adulthood ? Often associated with – xerosis – a personal or family history of atopy ? asthma and allergic rhinitis – A geic basis that is influenced by environmental factors ? Immunoaberration – Serum IgE elevation and eosinophilia – Th2 predominance in acute lesions evolves into a predominance of IFN? producing T cells in chronic lesions Epidemiology ? 7095% of cases arise before the age of 5 years ? Prevalence – 1020% of schoolchildren。 usually tiny papules Chronic Illdefined Illdefined, spreads Evolution Acute Rapid (few hours after exposure) Not so rapid (12 to 72 h after exposure) Chronic Months to years of repeated exposure Months or longer。 car maintenance。 printing。 agriculture。 hairdressing。Eczema and Dermatitis 濕疹與皮炎 中山一院皮膚性病學教研室 章星琪 Xingqi Zhang. , . ? Contact Dermatitis ? Atopic Dermatitis ? Eczema ? Clinical features* ? Management* Eczema/dermatitis ? The terms are interchangeable – Denoting a polymorphic inflammatory reaction pattern involving the epidermis and dermis. – There are many etiologies and a wide range of clinical findings. ? Polymorphic inflammatory reaction – Acute: pruritus, erythema, and vesiculation。 medical, dental, and veterinary services。 horticulture。 painting。 construction。 exacerbation after reexpos. Causative agents occurs only above threshold level Relatively independent of amount applied Incidence May occur in everyone Occurs only in the sensitized Management of ICD ? Prevention – Avoid irritant or caustic chemical(s) by wearing protective clothing (., goggles). – If contact does occur, wash with water or weak neutralizing solution. – Barrier creams. – In occupational ICD that persists, change of job may be necessary. ? Treatment ? Acute – Identify and remove the etiologic agent. – Wet dressings with gauze soaked in Burow39。 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 relaps