292 THE URINE. 



with different individuals. Generally, ghicosuria occurs when 

 the amount of sugar ingested at one time exceeds 200 grammes. 

 There are many individuals, however, in which this occurs follow- 

 ing the administration of only 150 grammes, and there are others in 

 which the ingestion of 250 grammes does not cause glucose to 

 appear in the urine. Glucosuria following the ingestion of 100 

 grammes of grape-sugar is now regarded as abnormal, and there is 

 reason to believe that the hepatic insufficiency thus manifested may 

 be referable to a mild form of diabetes. The amount of sugar 

 which then appears in the urine rarely exceeds 3 per cent. The 

 glucosuria, moreover, is only temporary, and disappears as soon as 

 the ingestion of sugar (viz., starches) is diminished. Between this 

 form of glucosuria and the comman form of diabetes, in which 

 practically no sugar can be utilized by the body, but in which the 

 elimination ceases as soon as carbohydrates are withdrawn from the 

 diet, all gradations may occur. These forms are now generally 

 regarded as referable to a hepatic insufficiency. Quite different 

 from diabetes of this character, on the other hand, is the type 

 in which the glucosuria continues although no sugars are ingested. 

 In such cases a hepatic insufficiency need not necessarily exist, 

 and there is evidence to show that in these forms the formation 

 of glycogen may still occur. We must therefore assume that 

 other organs are primarily involved, and there is every reason to 

 suppose that the metabolism of muscle-tissue is here principally 

 at fault, and that the tissue has lost the power of decomposing 

 the sugar which reaches it from the liver. As a consequence, 

 increased destruction of muscle-tissue occurs, as the inability on 

 the part of these structures to decompose sugar amounts to the 

 same as though no sugar were present at all. The body therefore 

 furnishes glucose from its albumins to supply the apparent deficit, 

 and thus further increases the hypergluca)mia and the resulting 

 glucosuria. We accordingly find that even though the carbohy- 

 drates have been withdrawn from the food sugar still appears in 

 the urine. The increased destruction of the tissue-albumins is in 

 such cases sufficiently apparent from the progressive loss of flesh 

 which is so constantly observed. That certain nervous influences 

 may here be at work is probable, and we know, as a matter of fact, 

 that injury to a certain region in the floor of the fourth ventricle 

 is invariably followed by the appearance of glucose in the urine. 

 But, on the other hand, we may also imagine that the normal 

 decomposition of the sugar is prevented owing to the absence of 

 a glucolytic ferment or its corresponding kinase. In support of 

 this view is the fact that after extirpation of the pancreas death 

 invariably results with symptoms which are practically identical 

 with those seen in the gravest types of diabetes. Ligation of the 

 duct does not produce this effect ; and it is noteworthy, moreover, 

 that the glucosuria disappears when pieces of the pancreas are 

 transplanted under the skin or when fresh raw pancreas is given 



