Insulin administration may trigger type 1 diabetes in Japanese type 2 diabetes patients with type 1 diabetes high-risk HLA class II and the insulin gene VNTR genotype

http://press.endocrine.org/doi/abs/10.1210/jc.2014-1759

Abstract

Context:

Insulin administration causes various types of immune responses to insulin. We previously reported 3 cases of type 1 diabetes (T1DM) triggered by insulin administration in Japanese type 2 diabetes (T2DM) patients.

Objective:

The objective of this study was to collect information and characterize insulin-triggered T1DM immunologically and genetically.

Methods:

Data for 6 patients (4 men and 2 women) with insulin-triggered T1DM aged 59.5 ± 12.8 years were collected. Serum or urinary C-peptides, islet-related autoantibodies, insulin antibody, HLA or the insulin gene VNTR genotype were analyzed. Th1- or Th2-associated responses were evaluated using an ELISPOT assay.

Results:

None of the subjects had received insulin therapy nor had an autoantibody to GAD65 before insulin administration. After insulin administration blood glucose control deteriorated acutely without any apparent cause, while C-peptide levels rapidly decreased to insulin-deficient levels. The mean duration of insulin administration to the development of T1DM was 7.7 ± 6.1 months. Islet-related autoantibodies became positive, while insulin allergy or a high titer of insulin antibody was observed in several cases. All had T1DM high-risk HLA class II (IDDM1) and the insulin gene VNTR genotype (IDDM2). GAD-reactive and insulin-peptides-reactive Th1 cells, but not Th2 cells were identified in 2 of 4 cases.

Conclusions:

The findings suggest that insulin administration may have triggered TIDM in patients with T2DM. IDDM1 and IDDM 2 as well as autoreactive T cells may contribute to the development of T1DM. Developing insulin-triggered T1DM if a patient’s blood glucose control acutely deteriorates after insulin administration should be carefully considered.

freaky.

It would seem obvious that anybody with the genetic risk for T1 may come down with T1. The real question is why in the world we somehow thought that T2 immunized you against getting T1.