Immediate-type allergy against insulin itself: clinical and immunologic studies on a diabetic patient with insulin intolerance.

In this report clinical and immunologic data of a female diabetic patient with immediate-type allergy against insulin preparations of different species, including pancreatic human insulin, biosynthetic human insulin and semisynthetic human insulin are described. The determination of insulin-specific antibodies showed relatively high IgE-antibody titers in contrast to low IgG-antibody concentrations, which is in accordance with the assumption that the ratio of IgE- to IgG-insulin antibodies is important in the outcome of clinically manifest allergic reactions. Negative results for cutaneous delayed-type insulin hypersensitivity and for stimulation of lymphocyte blastogenesis exclude type IV immunopathogenic reaction in this insulin-allergic patient. Preliminary data suggest that inherited individual factors--such as DR2, DR3 positivity in this diabetic individual--might predispose diabetic patients to insulin allergy.