ACID AND AMMOXIACAL URINARY FERMENTATION. 



493 



One liter of urine contains 24.4 cu. cm. of gases; TOO volumes of 

 urinary gases obtained by exhaustion contain 65.40 volumes of carbon 

 dioxid, 2.74 volumes of oxygen, and 31.86 volumes of nitrogen. After 

 vigorous muscular activity the amount of carbon dioxid may be doubled. 

 The act of digestion also causes an increase, while drinking in large 

 amount causes a reduction. 



SPONTANEOUS ALTERATIONS IN THE URINE ON STANDING; 

 ACID AND AMMONIACAL URINARY FERMENTATION. 



When kept in a cool place, normal urine often exhibits a forma- 

 tion of newly developed acid acid urinary fermentation. This results 

 in consequence of the development of peculiar fermentative microor- 

 ganisms, both budding-fungi, as well as fission-fungi, and is ac- 

 companied by excretion of uric acid (Fig. 153, c), acid sodium urate 

 (b), and calcium oxalate 

 (d). The nature of the 

 fermentative process is not 

 as yet entirely known. Ac- 

 cording to Briicke, lactic 

 acid is formed from the / v g*& ^/l -*/'$ ' yj.?; \^~ 



S-ftA* '* < X-*l f ^ 



d - 



... b 



FIG. 153. Sediment due to Acid Urinary Fermentation: a, fer- 

 mentative budding-fungi; b, amorphous acid sodium urate: 

 c, uric acid; d calcium oxalate. 



sugar of the urine ; accord- 

 ing to Scherer, the germs 

 decompose the vesical mu- 

 cus and some urinary pig- 

 ment into lactic and acetic 

 acids. According to Roh- 

 mann, who observed acid 

 fermentation develop only 

 exceptionally, this is due to 

 acids that result from the 

 decomposition of sugar 

 and of alcohol accidentally 

 present. Also the occur- 

 rence of butyric and formic 



acids as products of the decomposition of other constituents of the urine 

 has been observed. These newly formed acids expel the uric acid from 

 the simple sodium urate, so that free uric acid and neutral sodium biurate 

 (acid sodium urate) must be formed. With the commencement of acid 

 fermentation, the urine appears to absorb oxygen. Even while the urine 

 has an acid reaction, it becomes turbid and exhibits the presence of nitrous 

 acid, whose source is as yet undetermined. The presence of nitrites is dis- 

 closed by the development of an intensely yellow color on addition of 

 potassium ferrocyanid and acetic acid. According to v. Voit and Hoff- 

 mann, phosphoric acid is detached from acid sodium phosphate, with the 

 formation of the basic salt, and partly displaces uric acid from sodium 

 urate and partly causes its transformation into biurate. 



On standing for some time, and more readily when exposed to heat, 

 the urine eventually undergoes ammoniacal fermentation (Fig. 154), 

 the urea being decomposed, with addition of water, into carbon 

 dioxid and ammonia, as a result of the development of the micrococcus 

 and the bacterium urese (Fig. 155), at times arranged like a string of 



