Allergic contact dermatitis Allergens

Irritant contact dermatitis results from first-time exposures to irritating substances such as soaps, plants, cleaning solutions, or solvents. Allergic contact dermatitis occurs after an initial sensitivity and further exposure to allergenic substances, including poison ivy, latex, and certain types of metals. 

The most frequent causes of allergic contact dermatitis in the United States include plants (poison ivy, poison oak, and poison sumac), metallic salts, organic dyes, plastic resins, rubber additives, and germicides.74 The most common skin patch test allergens found to be positive in patients along with potential sources of exposure are shown in Table 32.1.75 In patients with occupational contact dermatitis who were skin patch tested, the common allergens included carba mix, thiuram mix, formaldehyde, epoxy resin, and nickel.76... 

Kligman, A.M., The identification of contact allergens by human assay. II. Factors influencing the induction and measurement of allergic contact dermatitis. J. Invest. Dermatol., Al, 375, 1966. 

Liu YQ, Zhao B, Zhuang LH, et al. 1997. Path test reactions to the Chinese standard screening allergens in 1,135 patients investigated for allergic contact dermatitis. Am J Contact Dermat 8 141-143. 

Allergic contact dermatitis developed on the hands and face of two patients after exposure to latex examination gloves. Both patients were patch test negative to the usual rubber allergens, but both had a positive test reaction to TBBC. 

Isaksson M, Bruze M. Allergic contact dermatitis in response to budesonide reactivated by inhalation of the allergen. J Am Acad Dermatol 2002 46(6) 880-5. 

Xenobiotics can affect allergic disease in one of two ways. They can themselves act as antigens and elicit hypersensitivity responses, or they can enhance the development or expression of allergic responses to commonly encountered allergens, such as dust mite. Chemicals that act as allergens include certain proteins that can by themselves induce an immune response and low molecular weight chemicals (known as haptens) that are too small to induce a specific immune response but may react with a protein to induce an immune response that is then hapten specific. Haptens have been associated with both allergic contact dermatitis (ACD), sometimes called contact hypersensitivity... 

Lomholt, H., Rastogi, S.C., and Andersen, K.E., Allergic contact dermatitis from sodium dihydroxycetyl phosphate, a new cosmetic allergen Contact Dermatitis, 45, 143, 2001. 

PBMC-derived DC serve as a surrogate marker for Langerhans cells (LC) and the chemical allergen-induced changes in cell surface markers of DC produce a similar pattern to those that occur in LC which are the antigen-presenting cell in the skin that plays a key role in the development of allergic contact dermatitis (Ozawa et al. 1996). 

In 145 patients with eczema of the external ear canal, allergic contact dermatitis was diagnosed in one-third topical therapeutic agents, especially neomycin sulfate and probably polymyxin B, were the dominating allergens (22). 

A literature search could not reveal any publications about a possible allergenic activity of Stevia plants, dried leaves or stevioside itself Kinghom came to the same conclusions no published reports have appeared that would suggest that extracts of Stevia leaves are immunologically active when taken internally [36]. Similarly there is no evidence that any of the constituents of Stevia caused allergic contact dermatitis. 

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