Insulin hypersensitivity in type 1 diabetes: investigation and treatment with immunodepletion: Insulin hypersensitivity in type 1 diabetes: investigation and treatment with immunodepletion

A 12-year-old girl presented with type 1 diabetes which was well controlled for the first two years. Glycaemic control then markedly deteriorated with a very large increase in insulin requirement and the appearance of inflammatory nodules at injection sites. Immunoprecipitation studies showed this to be due to a type 3 hypersensitivity reaction with the generation of IgG autoantibodies binding to insulin itself. Trials of a wide range of different insulins and treatment with a hyposensitisation protocol provided no benefit. Following treatment with rituximab, antibody generation subsided. Since the clinical response was only partial she also received intravenous immunoglobulin. A reduced insulin requirement and better glycaemic control were achieved over time. These parameters have subsequently deteriorated again. Copyright (c) 2020 John Wiley & Sons.