Pathogenesis of Type 1 Diabetes Mellitus: A Brief Overview

Before the discovery of insulin, type 1 diabetes mellitus (DM) was a disease with acute evolution, leading to death shortly after diagnosis. During the first years of insulin therapy, the medical world was optimistic, even enthusiastic, considering that the therapeutic solution for the malady was found. Unfortunately this was only an illusion, because the patients started to develop chronic complications that shortened their lifespan and impaired their quality of life. In other words, insulin therapy transformed type 1 DM into a chronic disease. The prevention or the delay of the onset of hyperglycemia emerged as a new solution for the patients and, consequently, the understanding of the pathogenesis of the disease (a prerequisite for developing efficient preventive methods) became a priority for all the diabetologists involved in research. Almost 40 years have passed since the autoimmune theory regarding the pathogenesis of type 1 DM was imagined but, despite the tremendous research performed in this field since then, the prevention could not be obtained. The aim of this paper is to present the most important theoretic notions regarding the mechanisms that underlie the development of type 1 DM, in the way they are understood today.