Repeated open application tests with methyldibromoglutaronitrile in dermatitis patients with and without hypersensitivity to methyldibromoglutaronitrile.
ABSTRACT Contact allergy to and allergic contact dermatitis from methyldibromoglutaronitrile (MDBGN) have been frequently reported since the 1990s.
This study was initiated to help determine the optimal test preparation for MDBGN and to help determine the clinical relevance of such a contact allergy.
In 38 patients with positive (32 patients) or doubtful (6 patients) patch-test reactions to at least one of four test preparations of MDBGN in petrolatum at 1.0%, 0.5%, 0.3%, and 0.1% (all weight per weight [w/w]), a repeated open application test (ROAT) with moisturizers with and without MDBGN at 0.03% w/w was conducted on patients' upper arms for a maximum of 4 weeks. Seven patients not hypersensitive to MDBGN served as controls and went through the same procedure.
Nineteen (59.4%) of the 32 MDBGN-allergic patients developed a positive ROAT result on the arm on which the moisturizer containing MDBGN was applied whereas no patients with doubtful or negative reactions to MDBGN reacted (p = .002). A statistically significant association was found between the patch-test reactivity and the outcome of the ROAT (p < .001).
Patch testing with MDBGN at 0.3% and 0.1% will miss clinically relevant patch-test reactions to MDBGN.
Chapter: Cosmetics and Skin Care Products[show abstract] [hide abstract]
ABSTRACT: Contact allergy to ingredients of cosmetics is one of the most frequent causes of contact allergy. While patients may report reactions to fragrance items, preservative allergy may not be suspected. The reaction typically resembles eczema on the face or hands, although any body site may be affected. Products left on the skin are much more likely to cause allergic reactions than rinse-off products. Common allergens include fragrances (e.g., hydroxyisohexyl-3-cyclohexene carboxaldehyde, isoeugenol, etc.), preservatives (e.g., formaldehyde and formaldehyde-releasers, MCI/MI, paraben esters, etc.); hair dye chemicals (e.g., p-phenylenediamine), and less frequent allergens such as lanolin and propylene glycol. Patch testing is mandatory where allergy is suspected or in localized/difficult-to-treat eczema. Sometimes a repeated open application test (ROAT) is required when the patch tests are surprisingly negative. Mandatory ingredient labeling of cosmetic items in the EU facilitates allergen avoidance and EU-set limits on the concentration of known allergens seem to be reducing the incidence of allergic contact dermatitis to certain preservatives.12/2010: pages 591-605;