Positive Nitrogen Balance in Nephritis. 9 



6 (1070) 



The interpretation of a positive nitrogen balance in nephritis. 

 By Herman O. Mosenthal, M.D. 



[From the Medical Clinic of the Johns Hopkins Hospital, Baltimore.] 



In studying nitrogen metabolism in certain cases of nephritis, 

 a retention of this substance was observed. The conception of 

 the retention of nitrogen in nephritis, as understood by the 

 clinician, generally implies two facts: Firstly, that a positive 

 nitrogen balance is usually due to kidney insufficiency; secondly, 

 that the retained nitrogen is present in the body as waste-nitrogen 

 and circulates in the blood, in part, at least, as non-protein nitro- 

 gen. It is known from the work of Marshall and Davis 1 that urea 

 is evenly distributed throughout the body, except in certain 

 tissues, as the fat, bone, cartilage, etc., which do not take up urea. 

 In calculating the theoretical amounts of non-protein nitrogen to 

 be expected in the blood, it has been assumed that all the nitro- 

 gen which the body has metabolized and is about to excrete, in 



TABLE 1. 



Theoretical and Actual Values of Non-protein Nitrogen 

 of the Blood Resulting from Nitrogen Retention 

 in Certain Cases of Nephritis. 





N. of Blood 



— Mg. per. 100 c.c. 





N. Grams Retained 













At Beginning of 



At End of 



Theoretical Value at 



During Observation. 





Observation. 



Observation. 



End of Observation.' 



Case 1 



30 



37 



152 



93.0 



" a 



30 



38 



Il6 



65.0 



" 3 



35 



34 



93 



51.0 



" 4 



30 



37 



165 



101.4 



" 5 



39 



37 



119 



69.1 



" 6 



71 



74 



117 



35-3 



contradistinction to the nitrogen which the tissues are storing is 

 evenly distributed throughout the body as is the case with urea. 



1 Marshall and Davis: Jour. Biol. Chem.. 1914, XVIII. 53. 



* These figures represent the values obtained for non-protein nitrogen of the 

 blood at the beginning of the observation plus the theoretical value due to retained 

 nitrogen. 



