Causes and Diagnoses

Causes and Diagnoses of Eczema

Scientists have found that eczema is mostly caused by a genetic mutation that prevents your skin from protecting itself from allergens and irritants in the environment.

The gene filaggrin (filament aggregating protein) plays an important role in maintaining the skin barrier, preventing moisture from getting out of the skin and preventing outside substances from getting into the skin. People who have the genetic mutation don’t have a strong protective layer, which leads to:

  • Skin that is dry, itchy and painful
  • Skin that is sensitive and reacts to many skin care products
  • Higher risk of developing allergies to allergens that come in contact with the skin
  • Higher risk for getting a variety of skin and other infections

Eczema and allergies

Eczema is not an allergy, but some studies suggest that eczema may allow allergies to develop because allergens can cross the impaired skin barrier. Some patients with eczema may also develop allergic contact dermatitis, where exposure to certain chemicals, including those in consumer products, may cause a persistent rash that looks just like eczema.

Diagnosing eczema

Your physician can diagnose eczema during a physical exam and discussion of your symptoms. If you think you have an allergy, please mention it. Your physician may perform some allergy testing. Patch testing is often necessary to determine if you have allergic contact dermatitis. Skin prick testing is often necessary to determine the cause of respiratory allergies (hay fever) and food allergies.

Diagnostic Tests

  • Skin Prick Test

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