In order to understand eczema, you have to understand your skin. The skin is a protective covering over the entire body; it is the largest organ you have and the most exposed as well. This combination of expanse and exposure give your skin that chance to be affected by a multitude of things that can cause it irritation. Trauma (scrapes, cuts, etc), environmental allergens, and caustic substances are the main irritants of skin.

The skin is composed of three main layers: the epidermis (outside layer), the dermis (middle layer), and subcutaneous tissue (inner layer). These all have the ability to react to irritants by inflaming (swelling, often becoming fevered).

Your skin and how it works

In the Epidermis, you will find keratinocytes. These are cells harboring a variety of chemicals which are released when triggered by various irritants. Appropriate chemicals are released depending on the trigger, such as the cells that react when bacteria comes in contact with the skin or pigment being released from sunlight contact. Inflammation is often another result of the release of these chemicals (for example, too much sunlight and you have slight swelling, redness and fever).

Another cell you will find in the epidermis is the Langerhans cells. These cells send out antigens that come in contact with the skin to the immune system. If the immune system decrees the antigen harmful, the Langerhans cells are transported to the lymph nodes where inflammatory cells are sent into play. These inflammatory cells create the skin condition we know as eczema. Eczema is the most common type of inflammation in the skin, and under a microscope all forms of eczema (no matter what the visible symptoms look like) are identical.

Fibroblasts and mast cells are the only cells naturally found in the dermis. Fibroblasts produce collagen and mast cells control redness, swelling, and itchiness of inflammation. Mast cells also call other inflammatory cells to action; these cells include: basophils, eosinophils, and T cell lymphocytes. The last of these, lymphocytes, go directly to the area of skin that has been subjected to irritation and are the main reason behind the appearance of eczema.

The skin, rather than just being a barrier between you insides and the world, is actually the largest organ in your immune system. It is the first defense in protecting you from all of the harmful irritants in the world, attempting to fight them off before them can take root within your other vital systems. Correct functioning of this system is protection for you. Incorrect functioning often leads to chronic diseases, like eczema.

How does it go wrong?

When this immune process is not functioning correctly, it is referred to as dysregulation. One instance of dysregulation is the chapped lips you get from wind. The body recognizes a regular assault from the wind, which is not of the body, and begins to defend against it. You will also see this when your hands are in water very often. The epidermis is damaged by the outside element (or trigger) and inflammatory cells are called in to battle. The rub comes when too many inflammatory cells are on the battlefield, this is the actual process of eczema. It is important to remember that eczema covers all types of inflammation in the skin and in this case, the word is being used as just that.

Eczema as most people use the word is actually Atopic Dermatitis (AD). This is a severe reaction to an irritant. People with AD are naturally more allergic than others, usually exhibiting asthma and/or hay fever and have a family history of others with eczema, asthma, and/or hay fever. With over 20 genes responsible for your AD, it is no wonder that symptoms of AD vary from patient to patient.

Not only are there different symptoms in different people, but different organs are also affected, which is why some people have hay fever as opposed to asthma or eczema when exposed to the same allergen (allergy trigger) or irritant. Hay fever affects the nasal passages, while asthma and eczema affect the lungs and skin respectively. Patients may have any combination of these orgasm affected.

If you have eczema as most people use the word, you actually have AD. Your body over-produces inflammatory cells in reaction to allergens or irritants. This is the difference between the standard sneeze or two from most people while you may sneeze repeatedly (if your reaction is in the nasal passages). Other affected organs react the same way. Allergy shots may or may not help you for allergens, but not for caustic substances. Those must be avoided.