What's the difference between all these skin conditions I've read about?

Most of my doctors referred to my skin issue as "dermatitis" and then as more time passed, they realized it was "allergic contact dermatitis" which is also the same thing as "eczema". Confused yet?

There are a lot of different skin conditions where itchy, dry, bumpy skin are the symptoms. It can get confusing  So, what are their actual definitions?

I searched for an online medical encyclopedia and found Medline Plus which is a service of the U.S. National Library of Medicine.

medline_plus

The following are skin conditions I've been wondering about:

Eczema

... is a term for several different types of skin swelling. Eczema is also called dermatitis. It is not dangerous, but most types cause red, swollen and itchy skin. Factors that can cause eczema include other diseases, irritating substances, allergies and your genetic makeup. Eczema is not contagious.

The most common type of eczema is atopic dermatitis. It is an allergic condition that makes your skin dry and itchy. It is most common in babies and children.

Eczema is a chronic disease. You can prevent some types of eczema by avoiding irritants, stress, and the things you are allergic to.

Atopic dermatitis

... is a chronic (long-lasting) disease that affects the skin. It is not contagious; it cannot be passed from one person to another. The word “dermatitis” means inflammation of the skin. “Atopic” refers to a group of diseases in which there is often an inherited tendency to develop other allergic conditions, such as asthma and hay fever. In atopic dermatitis, the skin becomes extremely itchy. Scratching leads to redness, swelling, cracking, “weeping” clear fluid, and finally, crusting and scaling. In most cases, there are periods of time when the disease is worse (called exacerbations or flares) followed by periods when the skin improves or clears up entirely (called remissions). As some children with atopic dermatitis grow older, their skin disease improves or disappears altogether, although their skin often remains dry and easily irritated. In others, atopic dermatitis continues to be a significant problem in adulthood.

Atopic dermatitis is often referred to as “eczema,” which is a general term for the several types of inflammation of the skin. Atopic dermatitis is the most common of the many types of eczema. Several have very similar symptoms.

Hives (Urticaria)

... are welts on the skin that often itch. These welts can appear on any part of the skin. Hives vary in size from as small as a pen tip to as large as a dinner plate. They may connect to form even larger welts.

A hive often goes away in 24 hours or less. New hives may appear as old ones fade, so hives may last for a few days or longer. A bout of hives usually lasts less than 6 weeks. These hives are called acute hives. If hives last more than 6 weeks, they are called chronic hives.

Acute hives often result from an allergy, but they can have many other causes.

The medical term for hives is urticaria (ur-tih-CAR-ee-uh). When large welts occur deeper under the skin, the medical term is angioedema (an-gee-oh-eh-dee-ma). This can occur with hives, and often causes the eyelids and lips to swell. In severe cases, the throat and airway can swell, making breathing or swallowing difficult.

Seborrheic Dermatitis

... is a common, inflammatory skin condition that causes flaky, white to yellowish scales to form on oily areas such as the scalp or inside the ear. It can occur with or without reddened skin.

Cradle cap is the term used when seborrheic dermatitis affects the scalp of infants.

Neurodermatitis

... intensely itchy skin that is usually itchiest when the person is resting or relaxing.

This common eczema develops when nerve endings in the skin become irritated, triggering a severe itch-scratch-itch cycle. Common causes of nerve irritation include an insect bite and emotional stress.

I also visited the National Eczema Association's website for all the different types of eczema.

They're listed as:

  • atopic dermatitis
  • contact dermatitis
  • dyshidrotic dermatitis
  • nummular dermatitis
  • seborrheic dermatitis

These are the definitions of the conditions I hadn't looked up yet:

Contact Dermatitis (allergic or irritant)

... is a reaction that can occur when the skin comes in contact with certain substances, which can cause skin inflammation. Irritants are substances that cause burning, itching or redness. Common irritants include solvents, industrial chemicals, detergents, fumes, tobacco smoke, paints, bleach, woolen fabrics, acidic foods, astringents and other alcohol (excluding cetyl alcohol) containing skin care products, and some soaps and fragrances. Allergens are usually animal or vegetable proteins from foods, pollens, or pets. Contact dermatitis is most often seen around the hands or parts of the body that touched the irritant/allergen.

Dyshidrotic Dermatitis (pompholyx)

... is a blistering type of eczema, which is twice as common in women. It is limited to the fingers, palms and soles of the feet. Your hands may have itchy, scaly patches of skin that flake constantly or become red cracked and painful.

Nummular Dermatitis (discoid)

Dry skin in the winter months can cause dry non-itchy round patches. It can affect any part of the body particularly the lower leg. One or many patches appear, and may persist for weeks or months. Discoid eczema does not run in families, and unlike atopic dermatitis, it is not associated with asthma. It does not result from food allergy. It is not infectious to other people, although bacteria sometimes secondarily infect it. Discoid eczema is more common in males.

Seborrheic Dermatitis

Red, scaly, itchy rash in various locations on the body. The scalp, sides of the nose, eyebrows, eyelids, and the skin behind the ears and middle of the chest are the most common areas affected. Dandruff (as seborrheic, is caused by a fungal infection) appears as scaling on the scalp without redness. Seborrhea is oiliness of the skin, especially of the scalp and face, without redness or scaling. Seborrheic Dermatitis has both redness and scaling.

 

Are you displaying any symptoms of the conditions listed above? What do you do to help your skin heal?

 

Sources:

http://www.nlm.nih.gov/medlineplus/

http://www.skincarephysicians.com/eczemanet/neurodermatitis.html

http://www.aad.org/skin-conditions/dermatology-a-to-z/hives#.UU9eYxwf58E

http://www.niams.nih.gov/Health_Info/Atopic_Dermatitis/default.asp

http://www.nationaleczema.org/living-with-eczema/eczema-quick-fact-sheet