Protein contact dermatitis is a cutaneous condition, and was a term originally used to describe an eczematous reaction to protein-containing material in food handlers. Usually affecting the hands or forearms, it manifests clinically as a subacute or chronic

dermatitis Dermatitis is inflammation of the skin, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can v ...

that recurs frequently over time. Niels Hjorth and Jytte Roed-Petersen coined the phrase "protein contact dermatitis" in 1976.

Signs and symptoms

Protein contact dermatitis appears as urticarial or vesicular skin reaction within minutes of contact with the causative protein on previously afflicted skin; nonetheless, chronic or recurring

eczema Dermatitis is inflammation of the Human skin, skin, typically characterized by itchiness, erythema, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become lichenification, thick ...

is the most frequently reported clinical picture. The most common affected areas are the hands (fingers, wrists, and forearms), although

can also occur on the face and neck (caused by airborne particles) in certain cases. Certain foods have been linked to a few occurrences of chronic paronychia, which is accompanied by erythema and

edema Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's Tissue (biology), tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels t ...

of the proximal nail folds.

Causes

Protein contact dermatitis is typically caused by food-related, proteinaceous etiologic agents, such as cereal grains, flours, enzymes, and proteins from vegetables and animals.

Mechanism

Similar to immunologic contact urticaria, the pathophysiology is a

type I hypersensitivity Type I hypersensitivity (or immediate hypersensitivity), in the Gell and Coombs classification of allergic reactions, is an allergic reaction provoked by re-exposure to a specific type of antigen referred to as an allergen. Type I is distinct fro ...

reaction mediated by allergen-specific

IgE Immunoglobulin E (IgE) is a type of antibody (or immunoglobulin (Ig) " isotype") that has been found only in mammals. IgE is synthesised by plasma cells. Monomers of IgE consist of two heavy chains (ε chain) and two light chains, with the ε c ...

within a previously sensitized individual. Although the precise mechanism underlying protein contact dermatitis is yet unknown, it may resemble that of

atopic dermatitis Atopic dermatitis (AD), also known as atopic eczema, is a long-term type of inflammation of the skin (dermatitis). It results in puritis, itchy, red, swollen, and cracked skin. Clear fluid may come from the affected areas, which often thickens o ...

, especially given that a delayed

-mediated reaction may be caused by

receptors on epidermal Langerhans cells.

Diagnosis

Patch tests are typically negative, so the diagnosis is made using the results of a

prick test Skin allergy testing comprises a range of methods for medical diagnosis of allergies that attempts to provoke a small, controlled, allergic response. Methods A microscopic amount of an allergen is introduced to a patient's skin by various means ...

with the allergen, which is thought to be the gold standard. Certain

antibodies An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the ...

may occasionally be found in the patient's serum.

Treatment

Usually, the eruption heals quickly when the causative material is avoided.

Corticosteroid Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involv ...

ointments or lotions expedite the healing process in extreme situations.

References

External links

{{Dermatitis and eczema Contact dermatitis