Diabetes related autoimmunity in gestational diabetes mellitus: Is it important?

Some GDM women show autoantibody positivity during and after pregnancy and pancreatic autoantibodies can appear for the first time in some patients after delivery. Autoantibody positivity is often accompanied by a high frequency of DR3 and DR4 alleles, which are classically related to the development of type 1 diabetes and, although not all studies agree on this point, by an immunological imbalance expressed by the behaviour of the lymphocyte subpopulation, which can be seen as diabetic anomalies overlapping with the immunological changes that occur during pregnancy. It is worth emphasizing that such patients may develop classical type 1 diabetes during and/or after their pregnancy or they may evolve, often some years after their pregnancy, into cases of latent autoimmune diabetes of adulthood (LADA). Autoimmune GDM accounts for a relatively small number of cases (about 10% of all GDM) but the risk of these women developing type 1 diabetes or LADA is very high, so these patients must be identified in order to prevent the severe maternal and fetal complications of type 1 diabetes developing in pregnancy, or its acute onset afterwards. Since women with autoimmune GDM must be considered at high risk of developing type 1 diabetes in any of its clinical forms, these women should be regarded as future candidates for the immunomodulatory strategies used in type 1 diabetes. (C) 2009 Elsevier B.V. All rights reserved.