IgE-mediated allergy to recombinant human insulin in a diabetic

A 63-year-old nonatopic female suffering from type II diabetes with severe local and systemic immediate-type allergic reactions to injections of different recombinant human insulin products has been reported. Skin testing as well as IgE measurements not only proved immediate-type sensitization to human insulin but also to porcine and bovine insulin which had never been administered and indicated immunological cross-reactivity. Cross-reactivity was proved by an IgE inhibition test. Independent of this reaction, the patient showed IgE-mediated sensitization to protamine.