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

Related Resources

  • Medical Outcomes Research in Eczema (MORE): MORE is a study of patient-centered outcomes in adults and children with eczema. Researchers in the Northwestern University Department of Dermatology are conducting this study. We want to hear what patients have to say about their eczema and what bothers them the most from having eczema. To participate in the survey you must be at least 18 years of age and have chronic eczema, or be the parent of a minor child with chronic eczema.
  • National Eczema Association: Improving the health and quality of life for individuals with eczema through research, support and education.
  • Society for Investigative Dermatology (SID): The SID mission is to advance and promote the sciences relevant to skin health and disease through education, advocacy and scholarly exchange of scientific information.
  • American Academy of Dermatology: Our mission is to promote leadership in dermatology and excellence in patient care through education, research and advocacy.
  • Severe Eczema in Children Linked to Multiple Comorbid Conditions: Researchers set out to determine the impact of eczema severity on the development of these disorders and other non-atopic comorbidities in atopic dermatitis. (The Dermatologist, September 2013)
  • Childhood Eczema May Last Into Adulthood: Study: Despite a widespread belief that childhood eczema clears up by adolescence, a new study suggests the condition often lasts until adulthood. (Reuters, April 2014)