Allergic contact dermatitis can show many different characteristics depending on many factors.
The following symptoms and complaints may indicate allergic contact dermatitis:
Leading symptoms of acute allergic contact dermatitis.
- Rapid onset of sharply defined erythema (extensive reddening of the skin) at the site of contact (e.g., hand eczema) with the substance
- If necessary, with abrinnspuren, itchy blisters with crust formation and desquamation.
Acute allergic contact dermatitis usually heals very quickly when the exposure is over.
Leading symptoms of chronic allergic contact eczema:
- Hyperkeratosis – excessive keratinization.
- Lichenification – thickening / coarsening of the skin fielding.
- Rhagades (fissures; narrow, cleft-shaped tear that cuts through all layers of the epidermis (cuticle)).
- Skin lesions are rather blurred boundary, the skin texture coarsens
Predilection sites (body regions where the disease occurs preferentially):
- Head
- Hands
Accompanying symptoms of contact dermatitis of the hands:
- Nail symptoms (frequency of nail involvement; about 80%): transverse grooves, brittle nails (brittle nails), paronychia (nail bed inflammation), hyperkeratosis (excessive keratinization) or loss of cuticle (cuticle) and eponychium (epithelium resting in the nail pocket dorsal to the nail plate).
Other notes
- Allergen contact is usually direct mechanical on the skin surface, it can also be aerogenic (mediated through the air),
- Aerogenic contact dermatitis can be easily differentiated from photoallergic contact dermatitis by the fact that it occurs preferentially in areas exposed to light. Inspection of the retroauricular and submental region (behind the ear and under the chin), which tends to remain clear in light-dependent reactions, helps.
- Allergic contact dermatitis tends to be scattered, meaning it is not limited to the site of contact.
- Irritant-toxic contact dermatitis often precedes allergic contact dermatitis. Often affected are the hands, which are thereby directly damaged mechanically or by surfactants contained in soaps.
- A special form of allergic contact dermatitis is shiitake dermatitis. The skin shows thereby tree-like branched linear redness, which has led to the names “flagellant dermatitis”. The cause is lentinan (glucan), a substance that can directly cause inflammation.
- In protein contact dermatitis/contact urticaria, biological substances such as latex (latex contact urticaria) or food can be detected as triggers (e.g., wheat) by a prick test. Frequently, these patients also have atopic eczema. The diagnosis can be confirmed by a specific IgE reaction to suspicious material/allergen.
