Sorbitan sesquioleate (SSO), sorbitan monooleate (SMO), and related compounds are increasingly recognized contact allergens. Sorbitan sesquioleate and SMO are nonionic emulsifying agents derived from sorbitol.1
Sorbitan sesquioleate, SMO, and other sorbitol derivatives are used as emulsifiers and dispersing agents in cosmetics, topical medications, topical emollients, produce, and other commercial products. Related compounds also are found in foods such as apples, berries, cherries, and sucrose-free cakes and cookies.1 We present a case of allergic contact dermatitis (ACD) with positive patch testing to sorbitans and clinical correlation with beer and bread exposure.
A 62-year-old man presented with a persistent pruritic rash of 6 months’ duration. Erythematous eczematous papules and plaques were observed on the face, neck, chest, abdomen, back, and upper and lower extremities, affecting approximately 60% of the body surface area. His current list of medications was reviewed and included a multivitamin, fish oil, and vitamin C. A punch biopsy revealed spongiotic dermatitis with eosinophils. Patch testing using the North American Contact Dermatitis Group Standard Series with supplemental allergens found in toiletries revealed a positive reaction to SSO and SMO that was persistent at 48 and 96 hours. Notably, patch testing for sodium benzoate, nickel, potassium dichromate, and balsam of Peru were negative. Investigation into the personal care products the patient used identified the presence of sorbitol solution in Vanicream bar soap and Vanicream moisturizing cream (Pharmaceutical Specialties Inc). These products were started after the development of the rash and were discontinued after positive patch testing, but the patient continued to experience the eruption with no improvement.
Retrospectively, the patient was able to correlate exacerbations with drinking beer and eating sandwiches. He habitually ate a sandwich on the same type of bread every single day and enjoyed the same brand of beer 2 to 4 times per week without much variation. To limit allergens, the patient gave up the daily sandwich and avoided bread altogether, noting remarkable clinical improvement over a few weeks. Later, he described even more improvement while on a trip where he did not have access to his usual beer. The eruption recurred when he returned home and excessively indulged in his favorite beer. He also noted recurrence with exposure to certain breads. No new lesions developed with avoidance of beer and bread, and he had less than 1% body surface area involvement at 2-month follow-up and 0% involvement at 1 year. For educational purposes, follow-up patch testing was performed using Vanicream sorbitol solution and the specific beer and bread the patient consumed. The Vanicream solution was obtained from the manufacturer. The beer was placed directly onto a test disc. The bread was moistened with a drop of saline and then placed directly onto a test disc. All were negative at 48 and 96 hours.
We report a case of systemic ACD with a positive patch test to sorbitans that was exacerbated with consumption of beer and bread and resolved with avoidance of these products. Although it was determined that the patient used personal care products containing a sorbitol solution, discontinuation did not result in clinical improvement. Sorbitol, sorbitans, and sorbitol derivatives are not commonly reported in the ingredient lists of foods such as beer and bread. Both beer and bread are created with the addition of yeast cultures, for fermentation in beer and for leavening in bread. Sorbitol is used as an osmotic stabilizer in the preparation of yeast strains2 and also is a by-product of fermentation by certain bacteria3 found in beer. Additionally, review of commercially available preparations of baker’s and brewer’s yeasts, such as Fleischmann’s and Red Star, list sorbitan monostearate in the ingredients.4-7 We propose that trace amounts are present in the yeast preparations for brewing and baking.
In this case, the offending beer and bread were locally made products (Abita Beer, Covington, Louisiana; Leidenheimer Bread, New Orleans, Louisiana). Both companies were unable to share their yeast sources, limiting our ability to confirm the use of sorbitol in their preparation. We hypothesize that if sorbitol is commonly used in yeast culture preparation and can be a by-product of fermentation, then it is present in trace amounts in many beers and breads and is not specific to these two products.