While there appears to be some relationship between dust mite allergens and atopic dermatitis (the clinical name for eczema), it does not seem to be a cause and effect phenomenon, at least not in the sense that dust mites cause eczema. The reverse might be true, as eczema does appear to predispose a person to allergies.

Expression of Atopic Dermatitis

Eczema is a skin condition often expressed in infants and children as a red, intensely itchy facial rash (scratching the itch provokes the rash). A family history of eczema, asthma, or even allergic rhinitis can be an indication of a possible predisposition for eczema in a child. Children can outgrow eczema, or it may continue or even reappear when they become adults.

Adults with eczema often suffer periodic bouts of extreme itchiness, which when scratched or rubbed results in rashes, frequently at joints such as the elbow or knee, but a rash can appear nearly anywhere on the body. Chronic eczema results in thickened, scaly, leathery patches of skin from constant scratching of itches.

Two fairly universal characteristics seem to be at the foundation of eczema: the skin of eczema patients is much drier than normal, unable to retain water as easily as the skin of most people. Also, the skin is easily inflamed. Just what sets off that inflammation is the major point of controversy.

Allergies and Eczema

Skin tests for sensitivity to allergens in eczema patients usually yield allergic-type responses, but these are often, if not always, interpreted as “false positives,” indicative only that the skin is sensitive to irritants in general, not necessarily specific allergens. However, having eczema is often a strong indicator that a child may develop allergies and/or asthma as they mature.

Dust Mites and Eczema

There appears to be little debate that even if eczema patients are not outright allergic to dust mites, the mites and their allergens are certainly an irritant that can trigger a flare-up of atopic dermatitis. It simply becomes difficult to qualify that relationship because so many other substances and circumstances can result in a flare-up:

• Dry air
• Temperature extremes
• Cigarette smoke
• Chemicals
• Coarse fabrics such as wool
• Certain foods, either by consuming them or contacting them