GENUINE DIABETES MELLITUS 529 



stood when we consider, that, as v. Noorden emphasizes, that fat is transmitted 

 to the blood and the tissues especially by the lymphatic paths, and from there 

 is transported to the liver only in accordance with needs, while carbohydrates 

 and protein directly flow to the liver through the portal vein and increase 

 the condition of irritability of the liver. The facts that, apart from theoret- 

 ical considerations, speak for the formation of sugar from fat: In severe cases 

 of diabetes mellitus we sometimes observe a not inappreciable increase of 

 sugar elimination when we administer large quantities of fat during a hunger 

 period. In such cases the dextrose to nitrogen quotient sometimes raises to 

 10. Further cases are known in which on abundant ingestion of fat the dex- 

 trose to nitrogen quotient is found higher than in the period of less fat in- 

 gestion. Finally, we have the results of exact metabolism investigations in 

 cases of very severe diabetes, which show that for long protracted periods 

 so great quantities of sugar eliminated that these cannot be explained by 

 the changes in protein and carbohydrates, v. Noorden has therefore men- 

 tioned that the conclusions drawn from the dextrose to nitrogen quotient as 

 to the extent of the formation of sugar out of protein in human diabetes, are 

 faulty, as we do not know the source of the sugar. 



In one group of diabetics this regularity, as just described, between the 

 sugar-value of the food and sugar eliminations exists in much less well ex- 

 pressed manner; indeed it may even happen that this law may be broken 

 down by other factors. I shall describe in detail later the nervous glycosurias 

 dependent on organic foundations. I shall cite here only the psychical fac- 

 tor. Any psychical agitation, a fright, a great excitation on account of a 

 case of death in the family, or business cares, can suddenly lead to an out- 

 break of the diabetes. The glycosuria may attain a high grade; lassitude, 

 great thirst, polyuria, induce the patient to consult the physician, who then 

 finds sugar. 



Often a slight limitation of the diet suffices to bring about a disappearance 

 of the sugar, or the sugar disappears spontaneously. In a short time, normal 

 tolerance is reestablished. At all events such cases as just mentioned are 

 exceptional. Ordinarily, also in this group of cases is the alimentary factor 

 plainly to be recognized; but this is small in comparison with the psychical 

 factors. In such cases we see not rarely that painful affections of any sort 

 at all may serve to increase the excretion of sugar. I naturally will not say, 

 concerning the category of cases in which the alimentary factor dominated 

 the scene, that also psychical excitements may not temporarily lower the 

 tolerance. In the nervous cases, however, the nervous factor predominates. 



The Protein Metabolism. The question of protein need in diabetes has 

 been studied in numerous metabolism investigations. In light and mod- 

 erately severe diabetics the protein need is certainly not increased; and even 

 in severe diabetics, as long as they are nourished rationally, we cannot speak 

 of an increased need for protein. This has long been shown by the protracted 



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