276 THE URINE. 



and possibly also pentoses, may be found at all times. Their 

 amount, however, is normally so small that their presence cannot be 

 recognized by the common tests. Larger amounts of carbohydrates 

 are found in health only during the puerperal state, and in the 

 course of lactation, when lactose is commonly present. Otherwise 

 the elimination of sugar in amounts which can be demonstrated by 

 the ordinary tests must be regarded as abnormal. 



Glucose. As I have indicated, glucose appears in the urine 

 whenever its amount in the blood exceeds 3 pro mille. This, 

 however, occurs only under abnormal conditions, and in the pres- 

 ence of small amounts the kidneys are manifestly capable of 

 preventing its passage into the urine. Under certain conditions, 

 however, this power is apparently lost, and we find, as a matter 

 of fact, that following the administration of phlorhizin glucosuria 

 occurs, although the percentage of sugar is not increased in the 

 blood. Whether or not such an insufficiency on the part of the 

 kidneys may also occur spontaneously we do not know. As a gen- 

 eral rule, however, glucosuria is associated with a hypergluchsemia. 

 This may result if unduly large amounts of sugar reach the liver, 

 so that the organ is incapable of transforming the entire quantity 

 into glycogen, and I have pointed out that the functional capacity 

 of the liver in this respect is of a much lower order than the 

 ability of the intestinal epithelium to transform polysaccharides 

 and disaccharides into glucose. The extent to which the liver 

 can normally transform glucose into glycogen seems to vary 

 with different individuals. Generally, glucosuria occurs when 

 the amount of sugar exceeds 200 grammes. There are many 

 individuals, however, in which this occurs following the admin- 

 istration 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 of the 

 type of 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 glu- 

 cosuria and the common 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 of whatever origin. Quite differ- 

 ent 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 



