Eczema (Atopic Dermatitis)

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Medical Author:

Gary W. Cole, MD

Gary W. Cole, MD

Dr. Cole is board certified in dermatology. He obtained his BA degree in bacteriology, his MA degree in microbiology, and his MD at the University of California, Los Angeles. He trained in dermatology at the University of Oregon, where he completed his residency.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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• Eczema Overview
• Eczema Causes
• Eczema Symptoms and Signs
• When to Seek Medical Care
• Exams and Tests
• Eczema Treatment
• Self-Care at Home
• Medical Treatment
• Next Steps
• Follow-up
• Prevention
• Outlook
• Support Groups and Counseling
• For More Information
• Web Links
• Synonyms and Keywords
• Authors and Editors
• Viewer Comments: Eczema - Symptoms and Signs
• Viewer Comments: Eczema - Effective Treatments

Eczema Overview

The term eczema is derived from the Greek, meaning "to boil out." The name is particularly apt since to ancient medical practitioners it may have appeared that the skin was "boiling." Today the usage is rather imprecise since it is frequently used to describe any sort of dermatitis (inflammatory skin conditions). Not all dermatitis is eczematous. All eczematous dermatitis has a similar appearance. Acute lesions are composed of many small fluid-filled structures called vesicles that usually reside on red, swollen skin. When these structures break, the fluid leaks out, causing characteristic weeping and oozing. When the fluid dries, it produces a thin crust. In older lesions, these vesicles may be harder to appreciate, but an examination of the tissue under the microscope will reveal their presence. Eczematous dermatitis has many causes. One of the most common is a condition called atopic dermatitis. Often those using the term eczema are referring to atopic dermatitis. Although atopy refers to a lifelong. inherited (genetic) predisposition to inhalant allergies such as asthma and allergic rhinitis (hay fever), atopic dermatitis is not an allergic disease. Atopic patients are likely to have asthma, hay fever, and dermatitis. Atopy is a very common condition, and it affects all races and ages, including young infants. About 1%-2% of adults have the skin rash, and it is even more common in children. Most affected individuals have their first episode before 5 years of age. For most, the disease will improve with time. For an unlucky few, atopic dermatitis is a chronic, recurrent disorder.

Other eczematous dermatoses include, but are not limited to, allergic contact dermatitis (cell-mediated allergy to a common substance such as poison oak or nickel), irritant dermatitis (from excessive contact with a chemical substance), fungal infections, scabies infestations, stasis dermatitis, asteatosis, pompholyx (dyshidrosis), nummular dermatitis, and seborrheic dermatitis. The differentiation among these conditions is often difficult and time-consuming. In addition, it is not uncommon for atopic dermatitis to coexist with another eczematous dermatitis.