SUGAR IN THE URINE. 501 



Landois observed them, also, in association with the passage of biliary matters 

 in consequence of marked destruction of erythrocytes. Their properties and 

 reaction have already been described (p. 315), a solution of cane-sugar 0.5 gram 

 to one liter of water being employed for the latter. Urine of low specific gravity 

 should be concentrated upon the water-bath. To insure absolute certainty, a 

 portion of urine is evaporated over the water-bath almost to dryness, and the 

 residue extracted with alcohol. The alcoholic extract is again carefully evaporated 

 in a porcelain dish, and the residue dissolved in a few drops of water and sub- 

 jected to Pettenkofer's test. If the test is applied directly to the urine, one 

 must previously have convinced himself that the urine is free from albumin, as 

 this substance yields a similar reaction. In such an event the albumin should 

 be removed by boiling and filtration. If filter-paper is dipped into urine to 

 which cane-sugar has been added, and the paper is dried and brought in contact 

 with sulphuric acid, a violet-red color results, which is particularly pretty in 

 transmitted light. 



SUGAR IN THE URINE: GLYCOSURIA. 



Normal urine contains traces of dextrose. Small amounts of sugar are present 

 after ingestion of sugar in large amounts (alimentary glycosuria) , and also in the 

 presence of fever, after the drinking of beer supplemente'd by alcohol, occasionally 

 in the exceedingly obese, in neurasthenics, in association with cerebral disease, 

 and in advanced age. Glycosuria occurs also as a result of failure in intestinal 

 activity in ill-nourished individuals; and, artificially, after ligation of the mesen- 

 teric arteries. Dextrosuria of considerable degree is a sign of diabetes mellitus. 

 In this connection, the large amount of urine, up to 10,000 cu. cm., as well as 

 the high specific gravity, from 1030 to 1040, are striking. The diabetic patient 

 excretes a relatively larger amount of water through the kidneys; and, on the 

 other hand, a relatively smaller amount through the skin (and the lungs?) than 

 a healthy person. Also the elimination of the water ingested takes place later 

 and more uniformly than in health. The urine is pale yellow in color, although 

 the amount of coloring-matter is, in the aggregate, by no means diminished; and 

 the nitrogenous matters are increased. A diet of carbohydrates generally in- 

 creases the excretion of sugar; while a proteid diet may reduce it. Uric acid 

 and calcium oxalate are often found increased at the commencement of the disease. 

 On standing for a considerable time yeast-cells constantly develop in the urine. 



For quantitative estimation the tests for sugar already described (p. 268) 

 are appropriate, although the urine must be free from albumin or be rendered 

 so. The following tests are most to be recommended: 



(a) The fermentation-test is the most reliable. A test-tube inverted over 

 mercury is filled with the saccharine urine and a piece of yeast, living and free 

 from sugar, as large as a pea, and also one drop of tartaric acid, are added, and 

 the mixture is kept in a warm place. Carbon dioxid collects at the bottom of 

 the inverted tube, and disappears after the introduction of potassium hydrate. 



(b) A 2.5 per cent, solution of copper sulphate and a solution containing 10 

 parts of sodiopotassic tartrate in 100 parts of a 4 per cent, solution of sodium 

 hydrate are employed. Five cubic centimeters of urine are boiled in a test-tube, 

 and from i to 3 cu. cm. of the copper-solution and 2.5 cu. cm. of the tartaric- 

 acid solution in a second test-tube. The boiling of both fluids is interrupted 

 simultaneously, and after the lapse of from 20 to 25 seconds, the contents of the 

 one tube are poured without agitation into the other; reduction then takes place 

 spontaneously . 



(c) Bottger's test with Nylander's modification (p. 267). 



(d) In the application of the phenylhydrazin-test, 5 cu. cm. of urine are 

 diluted with 5 cu. cm. of water, and 0.5 of phenylhydrazin hydrochlorate and i 

 gram of sodium acetate are added. The mixture is boiled for two minutes over 

 the water-bath, is permitted to cool slowly and to stand for four hours in the 

 cold. Combinations of glycuronic acid form similar, though plumper, crystals, 

 more like thorn-apples. 



(e) In applying Molisch's test, -naphthol dissolved in chloroform, instead of 

 in alcohol, is employed. The test discloses the presence of all of the carbohy- 

 drates in the urine, under normal circumstances 0.96 per cent, altogether, of which 

 o. i is grape-sugar. Urine containing sugar should be diluted 100 times. 



(/) If to 10 cu. cm. of diabetic urine in a test-tube 0.5 mg. of powdered gentian- 

 violet are added, the urine is colored, while normal urine is not. 



