On Indican in the Blood of Uremic Patients. 77 



cant since this would be suggestive of the nature of the abnormal 

 metabolism. Hence a recent report 1 to the effect that indican is 

 present in the blood in uremia invited confirmation, and especially 

 as the amounts present are stated to be sufficient to give the 

 ordinary blue color with chloroform when only 10 c.c. of serum 

 are used for the test. Considering the total volume of blood this 

 would mean an enormous concentration. 



The method for detecting indican employed by Obermayer, 

 was, in brief, to separate all of the proteins from the serum by 

 means of alcohol, which after filtration is evaporated on the steam 

 bath. The residue from the alcohol filtrate is taken up in water, 

 freed of salts with lead acetate and the latter in turn removed by 

 sodium phosphate. A water clear filtrate is the final result which 

 is tested by the usual method employed for urine with Obermayer's 

 reagent. 



In repeating Obermayer's experiments the method above 

 mentioned was used, also the separation of the proteins was con- 

 ducted by means of phosphotungstic and hydrochloric acids and 

 in a third series a method was used which is based on that of Rona 

 for the precipitation of colloids in blood, by means of kaolin. 

 The clinical material consisted of ten typical cases of uremia, all 

 of the convulsive type. It was noted that indican could not be 

 detected in fresh serum when 10 c.c. was used for tests; with 

 larger amounts, 25 c.c, a questionable coloration of the chloroform 

 resulted in one instance. If instead of using fresh serum or blood, 

 the material be allowed to stand twenty-four to thirty-six hours 

 many of the uremic bloods then gave a fairly definite reaction. 

 When the kaolin method of separation of proteins is employed, 

 however, no indican could be detected even though the equivalents 

 of as much as 50 c.c. of blood be used for the test. 



1 Obermayer and Popper, Zeitschr. f. Klin. Med., 1911, 72, pp. 333-72. 



