Sorbitan sesquioleate: a rare contact allergen that is also an important indicator of allergic contact dermatitis from crossreacting compounds as well as for false‐positive fragrance allergy

Abstract

Summary Background Controversy exists about the addition of sorbitan sesquioleate (SSO) to the European baseline series for concomitant patch testing, particularly with fragrance mix (FM) I and Myroxylone pereirae (MP), which both contain SSO as an emulsifier. Aim To investigate SSO contact sensitization and concomitant positive patch test reactions to FM I or MP in Turkey. Methods This was a retrospective analysis of 840 patients consecutively patch tested with SSO 20% petrolatum between 1996 and 2020. Results The prevalence of SSO sensitization was 0.6% (5 of 840). In four of the five patients, clinical relevance could be established from SSO crossreactants, mainly in moisturizers and topical pharmaceuticals other than corticosteroids. Positive patch test reactions with unknown clinical relevance were observed to FM I or MP (both containing 5% SSO) in 71.4% of patients with a positive/questionable positive reaction to SSO (P < 0.001) and to other patch test allergens containing 1–5% SSO. Conclusions SSO was a very good indicator for positive patch test reaction with unknown clinical relevance to fragrances and other allergens containing 1–5% SSO. We suggest that SSO should be tested as a negative control with any commercially available patch test allergen containing SSO at any concentration. Moreover, clinicians should be alert for SSO synonyms and for other sorbitan derivatives in product labels, as SSO itself might not be the culprit but an indicator for crossreacting allergens.

Use of sorbitan sesquioleate in patch test preparations and patch testing with the substance—What do our results mean?

“…The SSO contact allergy prevalence from this study (0.48%) remained similar to previous studies 10,18,19 . The prevalence of contact allergy to SSO in Europe was from 0.2% to 1.5% and seemed to be higher in other continents 5 .…”

“…The SSO contact allergy prevalence from this study (0.48%) remained similar to previous studies. 10,18,19 The prevalence of contact allergy to SSO in Europe was from 0.2% to 1.5% and seemed to be higher in other continents. 5 Our study found irritant reactions in only two patients suggesting that SSO could rarely cause skin irritation by patch testing.…”

Results of patch testing with five fragrance materials hitherto not tested: A dose‐finding study in the clinical population

“…This pattern of reactions was also found in this study, strengthening the assumption that the concentrations of the mixes and the individual fragrance preparations should be further investigated and reconsidered. SSO contact allergy prevalence in this study was 0.8%, which could affect the interpretation of patch test readings when some test preparations, as demonstrated in the results, that is, FM I and BOP, contain it as an emulsifier 44–47 …”

“…SSO contact allergy prevalence in this study was 0.8%, which could affect the interpretation of patch test readings when some test preparations, as demonstrated in the results, that is, FM I and BOP, contain it as an emulsifier. [44][45][46][47] Oakmoss and treemoss, with atranol and chloroatranol content at trace levels, were expected to elicit significantly fewer reactions in patients. 36 Interestingly, some patients reacted positively only to the test substances with trace levels of atranol and chloroatranol, in similar numbers to those who reacted positively to the test substances with the standard levels.…”