It`s characterized by the presence of a great quanity of glucose on blood ,causing excessive elimination of it through the urine.It happens mostly because of disturbance of the saccharide`s metabolism which makes the diabetic organism be unable to use these substances.It`s because of the pancreas, which doesn`t produce enough insulin.If the hyperglicemy gets extended, it will occur discompensation of the pancreas, which is reversible at the very beggining, but if the extension of the phenomenom is enough, it becomes definitve.