Contact Allergy to Alkyl Glucosides: A Review. Part 2.

This is the second part of a two-part narrative review of contact allergy and allergic contact dermatitis to alkyl glucosides (AGs), presenting patient demographics, products causing allergic contact dermatitis, patch test considerations, co-/cross-reactions, and the presence of AGs in cosmetics and other products. There are strong indications that atopic patients, or at least those with a history of atopic dermatitis, have an increased risk of becoming sensitized to AGs. This results in higher prevalences of sensitization to AGs in pediatric populations. Female sex does not appear to be a risk factor. The sites most commonly affected by allergic contact dermatitis are the face (+/- neck and scalp), hands, and "generalized." Occupational allergic contact dermatitis from AGs does not occur frequently and usually manifests as hand dermatitis from shampoos (in hairdressers) and hand cleansers. Cosmetics are by far (>80%) the most common products responsible for allergic reactions to AGs. Other culprit products include household and industrial cleansers, topical medications, wound foam dressings, and antiseptic products. Patch testing with commercial decyl glucoside (5% pet.) and lauryl glucoside (3% pet.) results not infrequently in dubious (?+) and irritant reactions. There are concerns that some weak "allergic" reactions may actually be false-positive. Frequent coreactivity between AGs may be caused by cross-reactions, concomitant sensitization due to mixed alkyl chain compositions, common allergenic impurities, and overlapping composition of patch test materials. Cosmetics with the highest prevalences of one or more AGs are cleansing products for babies and children.