Diabetes mellitus – um «continuum» fisiopatológico

Abstract

IntroductionDiabetes mellitus is mainly subdivided into type 1 diabetes (DM1) or type 2 (DM2). The existence of genetic, metabolic and immunological mechanisms involving these two entities, and clinical evidence of an autoimmune form of diabetes diagnosed in adults (LADA), suggests the possibility of a pathophysiological continuity. ObjectiveTo describe the main genetic, immunological and metabolic mechanisms common to the development of DM1 and DM2. To support the hypothesis of a pathophysiological continuum between the two main subtypes of diabetes. MethodsSystematic search in PubMed database of the original articles or systematic reviews published until April 2013. The search terms used were: «type 1 diabetes mellitus», «type 2 diabetes mellitus», «latent auto-immune diabetes in adults», «pathophysiology». ConclusionsLADA assumes, under the pathophysiological point of view, an intermediate position between DM1 and DM2, sharing genetic and immunological mechanisms. It was found that self-reactivity and apoptosis of the β cell are not exclusive processes of DM1, and that insulin resistance, being a key factor in the pathogenesis of DM2, determines a more rapid progression of DM1. Phenotypic expression of diabetes results from the imbalance created between these pathophysiological mechanisms, along the course of the disease. More than the classification of the patient in a subtype of diabetes it is the recognition of mechanisms leading to metabolic changes that allows an adequate therapy. The definition of LADA as an isolated entity could be withdrawn.