Eczema, which is also known medically as dermatitis [meaning inflammation of the skin], is not one single skin condition. There are several distinct kinds of eczema and it is not unusual for a person to have problems with more than one type of eczema.

Two of the more common forms of eczema are:

(a) atopic dermatitis is the most common form of eczema with intense itching which can be very debilitating, particularly for children who are those most likely to develop it.

The extremely itchy patches of skin, which may develop more frequently on the face and scalp in very young children and on hands and feet in older children.

These itchy patches, characterized by redness, swelling and cracking may bubble and ooze fluid or, in some cases, be dry, red and scaly.

If the condition is not treated properly, the skin often tends to thicken as a protection to avoid damage from scratching

(b) contact dermatitis can result from the skin coming into contact any one of a number of objects in everyday life. If the contact leads only to mildly irritated skin, the eczema is called irritant contact dermatitis, and this occurs frequently. Irritant contact dermatitis results from frequent exposure to mild irritants, such as detergent and shampoo. The affected skin becomes so sensitive that often other mild substances, even water can make the condition worse.

- if however, the contact produces an allergic reaction in the skin, the eczema is known as allergic contact dermatitis.

Allergic contact dermatitis occurs when the skin develops an allergic reaction to the contact with a substance, rather than being merely irritated by it. The most common substances which can cause allergy include some antibiotic ointments and the leather, glues and rubber in shoes and clothes.

Other major contributors listed among the causes of this allergy related eczema have been identified as:

- fragrances in perfumes, makeup and shampoos;
- some metals, such as nickel, which are commonly used in manufacturing jewelry;
- and some common plants like poison ivy, poison oak, or poison sumac.

In addition to these two relatively widespread types of eczema, there are a number of less common types including:

- dyshidrotic dermatitis is an eczema which occurs only on the sides of the fingers, the palms of the hands and on the soles of the feet. It often produces small blisters.

- neurodermatitis occurs when nerve endings in the skin become irritated and this sets off a severe itch-scratch-itch cycle.

- nummular dermatitis often appears following an injury to the skin like an insect bite, an abrasion or a burn. Circular or oval patches appear and may last for months.

- seborrheic dermatitis, called cradle cap in infants and dandruff in older children and adults, is a form of eczema which usually appears on the scalp as waxy, oily patches but can spread to the face;

- stasis dermatitis, also known as venous eczema, can occur when circulation problems in the legs allow fluids to build up and swell the legs. This eventually affects the skin, causing an itchy rash and leaving the skin discolored.

It is often difficult to identify the specific cause, or causes, of some of these less widespread forms of eczema. If the causes can be identified, such as in contact dermatitis, it is often possible to eliminate the offending substance and so reduce the incidence of the eczema.

Our next article in this series will discuss some of the treatments available to alleviate eczema symptoms and, with some of the forms, to the eradicate the problem.