[Pathogenesis of diabetes mellitus].

Following the discovery of von Mering and Minkowski (1889) that diabetes followed pancreatectomy, and the later discovery that a pancreatic hormone, insulin, would reverse all the changes characteristic of diabetes, it became natural to regard diabetes mainly as an insulin-deficiency syndrome. Certainly many cases of human diabetes are due to deficiency of insulin, as evidenced by the low blood insulin levels, an observation first made over 15 years ago (Bornstein and Lawrence, 1951). This type of diabetes is typically seen in the young. Figure 1 shows serum insulin levels in such patients. The onset is often sudden. Hyperglycaemia may be intense and ketonuria marked. There is in addition a considerable loss of urinary nitrogen due to excessive gluconeogenesis. Diabetes of this type does not differ radically from that seen, for