[Granulomatous allergic reaction of the delayed type to surfen].

In the last five years, a distinct increase of allergic reactions to surfen, a constituent of various insulin preparations, was observed. The allergic reactions were tuberculoid granulomas of the delayed type (type IV of Gell and Coombs). Intracutaneous tests with surfen or surfen-containing insulin preparations confirmed the diagnosis. Dermal infiltrates and mild erythema developed 24 to 96 hours after the injection of insulin. In some patients a post-inflammatory pigmentation was noted. Histological examination of the lesions and the intracutaneous test sites revealed a granulomatous inflammation without signs of foreign body reaction. At present, the cause of the increased incidence of allergic reactions to surfen remains hypothetical.