382 



PHYSIOLOGICAL CHEMISTRY 



states that the muscular efficiency of the individual depends upon the 

 intensity of this process. Under normal conditions about i-ij^ gram 

 of creatinine is excreted by an adult man in 24 hours, 1 the exact amount 

 depending in great part upon the nature of the food and decreasing 

 markedly in starvation. Very little that is important is known regard- 

 ing the excretion of creatinine under pathological conditions. The 

 creatinine content of the urine is said to be increased in typhoid fever, 

 typhus, tetanus, and pneumonia, and to be decreased in anaemia, chloro- 

 sis, paralysis, muscular atrophy, advanced degeneration of the kidneys, 

 and in leukemia (myelogeneous, lymphatic and pseudo). An increase 



FIG. 123. CREATININE. 



of creatinine was also noted in diabetes, an increase probably due to the 

 creatinine content of the meat eaten. The greater part of the data, 

 however, relating to the variation of the creatinine excretion under 

 pathological conditions are not of much value since in nearly every 

 instance the diet was not sufficiently controlled to permit the collection 

 of reliable data. And further, until the advent of the Folin method 

 (see page 506) there was no accurate method for the quantitative 

 determination of creatinine. Shaffer has called attention to the fact 

 that a low excretion of creatinine is found in the urine of a remarkably 

 large number of pathological subjects, representing a variety of con- 

 ditions, and that it is therefore evident that the excretion of an ab- 

 normally small amount of this substance is by no means peculiar to any 

 one disease. A considerable increase in the creatinine content of the 

 blood has been observed in uremia. 2 



1 According to Shaffer the amount excreted by strictly normal individuals is between 7 

 and ii mg. of creatinine-nitrogen per kilogram of body weight. 



2 Folin and Denis: Jour. BioL Chem., 17, 487, 1914. 

 Myers and Fine: Jour. BioL Chem., 20, 391, 1914. 



