78 DIABETES MELLITUS 



mally high; i. e., over 0.1 per cent., and only when this quantity of sugar is 

 present can it be quantitatively estimated. If on boiling urine in an alkaline 

 solution of copper sulphate (Trommer's test) we immediately, not subse- 

 quently, obtain a red or reddish-yellow precipitate, or if on warming the 

 urine with phenylhydrazin and acetic acid on a water-bath for half an hour, 

 a distinct crystalline sediment is deposited, we may be sure that the glycosuria 

 is not physiologic. As possible sources of, error there may be mentioned the 

 presence in the urine of lactose, pentose, and combinations of glycuronie 

 acid (after the administration of chloral, chloralamid, etc.). Lactose and 

 pentose as well as combinations of glycuronie acid have a considerable power 

 of reduction, but we may readily distinguish them from dextrose by the 

 fermentation test and by polarization. 



In diabetes, then, we are concerned only with hyperglycosuria, or, in 

 other words, with cases in which the sugar exists in such quantities as to 

 react readily to the above mentioned tests. But hyperglycosuria may exist 

 independently of diabetes. The so-called alimentary glycosuria is a case in 

 point : a person whose urine does not contain sugar partakes of sugar or 

 sugar forming substances (starchy material, dextrin) in sweetened foods and 

 liquids, beer, bread or potatoes, etc. ; if sugar then appears in the urine so 

 that it may be detected by means of any of the ordinary quantitative tests, 

 this condition is designated alimentary glycosuria. 



In diabetics whose urine is temporarily free from sugar, this is of quite 

 regular occurrence. It also takes place in non-diabetics, but with this differ- 

 ence, that in the diabetic the sugar producers in the food — the flour in bread, 

 etc. — if consumed in large amounts give rise to glycosuria almost as surely 

 as the sugar itself, while this condition only occurs in the non-diabetic from 

 sugar and not from starchy substances. 



Therefore, glycosuria after the ingestion of sugar need not be diabetic, 

 but may be produced in normal persons even up to several per cent., provided 

 the sugar (grape-sugar, milk-sugar, or cane-sugar) is given upon an empty 

 stomach in amounts of 100 grams and over. If such a glycosuria occur after 

 the consumption of 100 grams of sugar (usually grape-sugar is used) when 

 the stomach is no longer empty, we are dealing with abnormal glycosuria, 

 i. e., alimentary glycosuria e saccharo. This may indicate diabetes or be the 

 first sign of the development of the disease; in other words, the person in 

 question may develop diabetes sooner or later, but not necessarily; the indi- 

 vidual need not be a diabetic, nor even become one. 



Taking as a criterion the nature of the processes concerned, let us now 

 attempt to differentiate between diabetic and non-diabetic glycosuria. 



In the diabetic, the organs which are concerned in the consumption of 

 sugar have suffered damage and are incapacitated for work ; they fail to extract 

 the sugar from the blood which is brought to them, or they return it to the 

 circulation, as they are incapable of utilizing it. Thus a hyperglycemia and 

 consequent glycosuria arises, provided the amount of sugar in the blood is 

 more than 0.2 per cent.-0.3 per cent., and this is a diabetic hyperglycemia 

 and glycosuria. The condition depends upon obstruction to the normal drain- 

 age of sugar from the blood by the organs of sugar metabolism, and it is for 



