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Fig 1.10 Diagnostic Criteria for Atopic Eczema Must have: Plus three of the following:

An itchy skin condition 1. History of itchy rash Infants: on cheeks Others: skin creases (elbows, knees, front of ankles or under neck) 2. History of asthma or hay fever (under 4: family history in first degree relative) 3. Generalised dry skin in the past year 4. Visible eczema Under 4: over convexities (cheeks, forehead, outer arms) Over 4: in creases (as in 1 above) 5. Onset in first two years of life

The diagnostic criteria for atopic eczema as agreed by a working party of the Royal College of Physicians, London in 1995 are given in Fig 1.10.

Laboratory investigations While there is no exclusive test to corroborate the diagnosis, 90% of patients will have a raised IgE level. This is the immunoglobulin that is associated with allergies. Total IgE level, and RAST tests for IgE to specific allergens can be helpful in planning management. These levels correlate well with reactions to skin-prick tests with the same substance (read at 20 minutes).

Histology Fig 1.11 Non-specific Histological Processes of Eczema

Spongiosis Inflammatory infiltrate Acanthosis Parakeratosis Hyperkeratosis

The histology of atopic skin disease is similar to that of all forms of eczema (Fig 1.11) (see also p. 14, Plates 2.1-2.3). In the acute stage there are characteristic large epidermal vesicles, but all stages of the disease show similar epidermal spongiosis, and infiltration with lymphocytes. The inflammatory process in the dermis includes vasodilation and extravasation of blood cells into the upper dermis. The presence of eosinophils amongst the infiltrate can be seen in all types of eczema. The basal layer of the epidermis is overactive and the even dermal pegs of a normal dermo-epidermal junction are replaced by great variations in thickness of the epidermis. Lichenification in chronic eczema shows histologically as a gross thickening (acanthosis) of the

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Profile for Christopher Bridgett

Atopic Skin Disease - A Manual For Practitioners  

An account of a new behavioural approach to the treatment of atopic eczema, written for practitioners, but also for patients

Atopic Skin Disease - A Manual For Practitioners  

An account of a new behavioural approach to the treatment of atopic eczema, written for practitioners, but also for patients