802 URINE. 



Sugar in Urine. 



The occurrence of traces of glucose in the urine of perfectly healthy 

 persons has been, as above stated (page 749), quite positively proven. If 

 sugar appears in the urine in constant and especially in large quantities, 

 it must be considered as an abnormal constituent. In a previous chapter 

 several of the principal causes of glycosuria in man and animals were men- 

 tioned, and the reader is referred to Chapters VII and VIII for the essen- 

 tial facts in regard to the appearance of sugar in the urine. 



In man the appearance of glucose in the urine has been observed 

 under various pathological conditions, such as lesions of the brain and 

 especially of the medulla oblongata, abnormal circulation in the abdomen, 

 diseases of the heart, lungs and liver, cholera, and many other diseases. 

 The continued presence of sugar in human urine, sometimes in very con- 

 siderable quantities, occurs in DIABETES MELLITUS. In this disease there 

 may be elimination of 1 kilogram or even more of glucose per day. 

 In the beginning of the disease, when the quantity of sugar is still very 

 small, the urine often does not appear abnormal. In the more developed, 

 typical cases the quantity of urine voided increases considerably, to 

 3-6-10 liters per day. The percentage of the physiological constituents 

 is as a rule very low, while their absolute daily quantity is increased. 

 The urine is pale, but of a high specific gravity, 1.030-1.040 or even higher. 

 The high specific gravity depends upon the quantity of sugar present, 

 which varies in different cases, but may reach 10 per cent. The urine is 

 therefore characterized in typical cases of diabetes by the very large 

 quantity voided, by the pale color and high specific gravity, and by its 

 containing sugar. 



That the urine after the introduction into the system of certain medici- 

 nal agents or poisonous bodies contains reducing substances, conjugated 

 glucuronic acids, which may be mistaken for sugar, has already been men- 

 tioned. 



Glucose in urine. The properties and reactions of this sugar have been 

 considered in a previous chapter, and it remains but to mention the methods 

 for the detection and quantitative determination of glucose in the urine. 



The detection of sugar in the urine is ordinarily, in the presence of not 

 too small quantities, a very simple task. The presence of only very small 

 quantities may make its detection sometimes very difficult and laborious. 

 A urine containing proteid must first have the proteid removed by coagu- 

 lation with acetic acid and heat before it can be tested for sugar. 



The tests which are most frequently employed and are especially 

 recommended are as follows: 



TROMMER'S Test. In a typical diabetic urine or one rich in sugar this 

 test succeeds well, and it may be performed in the manner suggested on 



