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Dermatitis (Eczema)

»	What is dermatitis and why is it so important?
»	What is atopy?
»	Why is atopic dermatitis becoming more common?
»	What are the diagnostic criteria for atopic dermatitis?
»	What is the underlying defect in patients with atopic dermatitis?
»	In atopic dermatitis, which comes first - the itch or the rash?
»	Why does atopic dermatitis itch?
»	Why do people like to scratch an itch?
»	Does psychological stress worsen atopic dermatitis?
»	Did John Phillip Sousa write the “Atopic March?”
»	How does atopic dermatitis present at different ages?
»	What physical findings are associated with atopic dermatitis?
»	What factors provoke or exacerbate atopic dermatitis?
»	How can your atopic patients relieve their pruritic agony and discomfort?
»	What is the role of antihistamines in atopic dermatitis?
»	Describe the “two-pajamas treatment.”
»	Is “hand dermatitis” a specific entity?
»	What is pompholyx?
»	How can pompholyx be managed?
»	Describe the typical presentation of nummular eczema.
»	What causes nummular eczema?
»	Is there a cure for nummular eczema?
»	How does seborrheic dermatitis present in children?
»	How does seborrheic dermatitis present in adults?
»	What causes seborrheic dermatitis, and with what disease states is it commonly found?
»	Discuss the treatment approaches to seborrheic dermatitis.
»	What is an “id” reaction, and what does it have to do with Sigmund Freud?
»	What are the most common settings for an id reaction and how should you treat it?
»	What do you call dermatitis that covers virtually the whole cutaneous surface?
»	How can you determine the cause of a patient’s exfoliative dermatitis?
»	What general treatment measures are used to treat patients with exfoliative dermatitis?

Why do people like to scratch an itch?

Scratching suppresses areas of the brain associated with negative experiences of pruritus and activates pleasure centers of the brain. In other words, there is an emotional reward for scratching. Unfortunately, scratching damages the skin and worsens dermatitis so that it itches even more. Therefore, people scratch even more and get caught in an “itch-scratch cycle” that they cannot exit without medical help or supreme levels of self-restraint.

Yosipovitch G, Ishiuji Y, Patel TS, et al: The brain processing of scratching, J Invest Dermatol 128:1806–1811, 2008.