Allergic Reactions to Insulin

Abstract

Two of five patients with acute systemic allergic reactions to insulin injection required desensitization. Immunologic studies consisted of direct skin testing with a variety of insulins which included human and synthetic insulins. Passive cutaneous transfer, leukocyte histamine release, and radioimmunodiffusion studies were also performed. Fifty diabetic patients without symptoms of insulin allergy were also selected for skin testing with a variety of insulin preparations. Results indicated that insulin allergy may be directed against the insulin molecule itself or against protein contaminants in the commercially available preparation, and that it can be mediated by IgE. Desensitization resulted in precipitous drops in reaginic antibody titers and cutaneous sensitivity, with the simultaneous induction of tolerance to insulin.