Atopic dermatitis

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1. BY ROBERT IGBEDE ATOPIC DERMATITIS

2. Atopic dermatitis (AD) is a pruritic disease of unknown origin that usually starts in early infancy; it is characterized by pruritus, eczematous lesions, xerosis, and lichenification. AD may be associated with other atopic (immunoglobulin E [ IgE ]– associated) diseases ( eg , acute allergic reaction to foods, asthma, urticaria, and allergic rhinitis INTRODUCTION

3. The prevalence rate for atopic dermatitis (AD) is 10-12% in children and 0.9% in adults (US) The prevalence rate of AD is rising, and AD affects 15-30% of children and 2-10 % of adults (international ). The frequency is increased in patients who immigrate to developed countries from underdeveloped countries. The male-to-female ratio for AD is 1:1.4. In 85% of cases, AD occurs in the first year of life; in 95% of cases, it occurs before age 5 years. The incidence of AD is highest in early infancy and childhood . EPIDEMIOLOGY

4. AD is basically the inflammation of the skin due to allergic reaction, when the immune system attacks the skin causing dry skin rashes ,which are common among small children The skin rashes are found on the flexor surfaces of the body such as –creases of the wrists, insides of the elbows, backs of knees It is due to TYPE 4 HYPERSENSITIVITY REACTION 1. Sensitization 2. Re- exposure ATOPIC DERMATITIS

5. Genetic A family history of atopic dermatitis (AD) is common. The strongest known genetic risk factor for developing AD is the presence of a loss-of-function mutation in filaggrin ( helps in water retention) . These genes encodes proteins involved in epidermal proliferation and differentiation or inflammatory cytokines. ETIOLOGY

6. The skin of patients with AD is colonized by S. aureus . Clinical infection with S aureus often causes a flare of AD, and S aureus has been proposed as a cause of AD by acting as a super antigen . Similarly, super infection with herpes simplex virus can also lead to a flare of disease and a condition referred to as eczema herpeticum . An aeroallergen is any airborne substance, such as pollen or spores, which triggers an allergic reaction. INFECTION AND AERO ALLERGENS

7. Two main hypotheses have been proposed regarding the development of inflammation that leads to AD : The first suggests a primary immune dysfunction resulting in IgE sensitization, allergic inflammation , and a secondary epithelial barrier disturbance . The second proposes a primary defect in the epithelial barrier leading to secondary immunologic dysregulation and resulting in inflammation PATHOLOGY

8. Erythema Crusted lesions on the face neck Erythematous macules that lichenifies with scratching Swelling Pruritis Weeping clear fluid Dry and itchy skin SIGNS AND SYMPTOMS

9. There is no cure for AD Lifestyle changes –avoid soaps ,avoid allergy triggers Skin care –use oil based moisturizers Medications -such as oral corticosteroids or antihistamines, are taken as pills , use of anti-inflammatory drugs TREATMENT

10. THANKS!!!