URINE. 121 



PATHOLOGICAL URINARY CONSTITUENTS. 



PROTEINS. 



Representatives of nearly every class of proteins have 

 been detected in urine at various times. Normal urine un- 

 doubtedly contains traces of these substances; thus, for 

 example, in the "mucous cloud" which separates out from 

 many urines upon standing a phosphoprotein can be demon- 

 strated. Of the proteins which appear under well-defined 

 morbid conditions, the most important are the albumins, 

 the globulins, and the proteoses. So-called peptone has 

 also been noticed. Since, however, the conception of the 

 properties of the mixture which passes under this name is 

 so ill-defined and changeable, it is probably better in the 

 future to dismiss the term peptonuria. Haemoglobin and 

 related substances may also escape from the blood into the 

 urine. 



ALBUMIN AND GLOBULIN. 



Serum albumin and serum globulin usually appear to- 

 gether in the urine under the name of albuminuria; but 

 concerning the relative quantities of the two bodies under 

 the various conditions very little is known. The two 

 proteins allow of separation in the same manner as was 

 employed under Blood Proteins, p. 73. 



In testing urines suspected of containing protein, the 

 fluid should always be perfectly clear. This can be accom- 

 plished either by repeated filtration through paper or asbestos 

 or by shaking with magnesia. 



The following tests are best suited for ordinary conditions: 



(a) Heat Test. Heat 5 c.c. of clear urine to boiling and add 



