Successful patch testing of a patient receiving anti-interleukin-17 therapy with secukinumab: a case report.

Conflicts of interest: D. Hamann is a first-degree relative of the owner of SmartPractice (Phoenix, AZ, USA), a company that sells dermatological diagnostic products, including patch test supplies. M. Zirwas is a consultant for the following companies: Valeant, Medimetricks, Exeltis, SmartPractice, Genetech, fitbit, and Sun Pharmaceuticals. because of a 6-month history of progressive pruritic dermatitis on the hands, arms, legs, and trunk. The eruption transiently improved during two short courses of systemic prednisone. Two biopsies of the new lesions showed eosinophilic spongiosis consistent with contact dermatitis, without features of psoriasis. Patch testing showed 1+ reactions to fragrance mix I and cinnamic aldehyde, and a 2+ reaction to sorbitan sesquioleate (SSO). The reactions to fragrance mix I and cinnamic aldehyde were deemed to be attributable to the presence of SSO in the allergen preparation. SSO was found as an ingredient in the patient’s clobetasol cream, and with avoidance he dramatically improved.