URINE 471 



Reading of Urine : Reading of Standard :: 50 : X. 



The amount of the drug eliminated normally is 40-60 per cent during 

 the first hour and 20-25 P er cent during the second hour, or a total of 

 60-85 per cent for two hours. The amount of the drug excreted has 

 been found to be independent of the quantity of urine obtained. 

 In case of delayed excretion the collection of hourly samples may be 

 continued until practically all of the drug has been recovered in the 

 urine. 



If it is desired to test the function of each kidney separately, 

 ureteral catheterization must be resorted to, the experiment other- 

 wise being performed as above described. 



The phenolsulphonephthalein test may be used to indicate the 

 amount of derangement in quantitative functional disturbance of the 

 kidneys, as in chronic interstitial and chronic parenchymatous neph- 

 ritis or uremia. 



McLean 1 has very recently suggested a method for studying kidney 

 function which is based upon the relationship between the urea con- 

 tent of the blood and the rate at which the urea is excreted by the 

 kidney. It gives similar values to the phenolsulphonephthalein test. 

 It has an advantage in that it enables one to measure kidney function 

 by a study of an actual normal function of the organ, i.e., urea excre- 

 tion. The method, however, is more or less complex. 



Mosenthal Test for Kidney Function. 2 Principle. The patient 

 under examination is placed for a day on a more or less definite diet 

 which should contain a sufficient quantity of protein, salt, fluid, and 

 purine derivatives, i.e., diuretic materials such as are present in an 

 ordinary diet. The urine is collected in six two-hour periods during 

 the day and one twelve-hour night period. These urine specimens 

 are analyzed for volume, specific gravity, total nitrogen, and chlorides. 



Procedure. On the day of the test have the patient empty the bladder at 

 8 A.M. and start the diet for the day which is selected to contain approximately 

 13-14 grams of nitrogen, 8-9 grams of salt, 1700-1800 c.c. of fluid, and con- 

 siderable purine material in meat, soup, tea, and coffee. 8 No solid food nor 

 fluid of any kind must be taken between meals and especial care must be ob- 

 served that nothing is eaten nor drunk during the night. The meals should 

 start at 8 A.M., 12 Noon, and 5 P.M. respectively. 



1 McLean: Jour. Am. Med. Ass'n, 66, 415, 1916. 



2 Mosenthal: Boston Med. and Su~g. Jour., 170, 245, 1914. 



3 A diet suitable to ordinary hospital conditions is given by Kahn: "Functional Diag- 

 nosis," p. 260, New York, 1920. It is emphasized that the diet need not be exactly the 

 same as that given since the foods found in the ordinary household contain sufficient diuretic 

 materials for the proper carrying out of the test. In private practice it is only necessary 

 to ask the patient to eat three full meals a day and write down the approximate quantities, 

 as i cup of coffee, two slices of toast, two tablespoonfuls of oatmeal, etc. 



