URINARY DEXTRINE 267 



istic color reaction of the blood in diabetes is supposed to 

 be due to the hyperglycaemia. It has been noted that diabetic 

 blood has the property of changing the color of methylene- 

 blue to a yellowish red, apparently by some reduction 

 process. Naturally it was supposed that the phenomenon 

 is referable to the reducing power of the sugar in the blood. 

 However, it was found that the red corpuscles of a diabetic, 

 after they have been entirely freed from the sugar-contain- 

 ing plasma by repeated centrif ugation with isotonic salt solu- 

 tion, fail to give the normal appearance of erythrocytes 

 (when stained with methylene-blue) . It is said, too, that this 

 blood test may be met in cases long after the sugar has dis- 

 appeared from the urine from withdrawal of carbohydrates. 

 It may be, of course, that even in such cases the proportion 

 of sugar in the erythrocytes is abnormally high. C. v. Noor- 

 den properly calls attention to the need of making quantita- 

 tive comparisons between the proportion of sugar in the 

 blood and staining qualities in order to gain an explanation 

 of this reaction. 62 



Another question which is connected with the hyper- 

 glycsemia is whether the increased proportion of sugar in 

 the blood in diabetes is necessarily due to an increased 

 * l impermeability of the kidneys for sugar. ' ' 



Urinary Dextrine. Very little attention has been given 

 to the question whether besides the sugar it is possible that 

 polymeric carbohydrates may also pass from the blood into 

 the urine in diabetes. Alf tan's 63 estimations of an aver- 

 age excretion of 0.15 gram of "urinary dextrine" for a 

 normal man and in severe diabetes of perhaps from 5 to 24 

 grams per diem apply here. The exact meaning of this 

 "urinary dextrine," chemical study of which is as yet 

 lacking, is another problem. 



451 C. v. Noorden, Handb. d. Pathol. d. Stoffw., 2d ed., 2, 104-105, 1907; 

 cf. therein Literature. 



83 K. v. Alftan, Ueber dextrinartige Substanzen im diabetischen Harne, 

 Helsingfors, 1904. 



