Contact allergy to sorbitans: a follow-up study

Area of Science:

• Dermatology
• Allergology
• Contact Dermatitis

Background:

• Sorbitan sesquioleate (SSO) is a common emulsifier in corticosteroid formulations.
• Previous studies indicated a positive patch test reaction rate of 8.9% for SSO in dermatitis patients.

Purpose of the Study:

• To evaluate the prevalence of contact allergy to sorbitan sesquioleate (SSO) and sorbitan monooleate (SMO) in dermatitis patients.
• To analyze patch test results for patients exposed to cosmetic products containing sorbitans.

Main Methods:

• A retrospective chart review of 591 dermatitis patients patch tested between November 2008 and May 2010.
• Patients were tested with a modified North American Contact Dermatitis Group standard series and a cosmetic series.

Main Results:

• Overall, 4.1% (24/591) of patients showed positive reactions to SSO and/or SMO.
• Specific reactions included 3.2% to SSO alone, 0.17% to SMO alone, and 0.68% to both.
• Among the 24 patients allergic to sorbitans, 8.3% (2/24) reacted to tested corticosteroid screening chemicals.

Conclusions:

• Contact allergy to SSO and/or SMO affects 4.1% of dermatitis patients.
• The frequent use of SSO in topical corticosteroids suggests a potential cause for treatment non-response.
• Dermatologists should consider sorbitan allergy in the differential diagnosis for patients with persistent dermatitis despite topical corticosteroid treatment.