404 PHYSIOLOGICAL CHEMISTRY. 



coloring matter nearly related to Ticematoporphyrin has been found by NEUSSER 

 in two pathological urines. MACMUNN has found a coloring matter, uroTicema- 

 tin, in rheumatism and ADDISON'S disease ; he also prepared it artificially from 

 haematin. This coloring matter seems also to stand in close relationship to 

 hsematoporphyrin. 



Pus occurs in the urine in different inflammatory affections, 

 especially in catarrh of the bladder and in inflammation of the mem- 

 brane of the kidneys or the urethra. 



Pus is best detected by means of the microscope. The pus-cells 

 are rather easily destroyed in alkaline urines. In detecting pus we 

 make use of DONNE'S pus-test, which is performed in the following 

 way: Pour off the urine from the sediment as carefully as possible, 

 place a small piece of caustic alkali on the sediment, and stir. If 

 the pus-cells have not been previously changed, the sediment is 

 converted by this means into a slimy tough mass. 



The pus-corpuscles swell up in alkaline urines, dissolve, or at 

 least are so changed that they cannot be recognized under the mi- 

 croscope. The urine in these cases is more or less slimy or fibrous, 

 and it is precipitated in large flakes by acetic acid, so that it may 

 possibly be mistaken for mucin. The closer investigation of the 

 precipitate produced by acetic acid, and especially the appearance 

 or non-appearance of a reducible substance after boiling it with a 

 mineral acid, demonstrates the nature of the precipitated substance. 

 Urine containing pus always contains albumin. 



Bile-acids. The statements in regard to the occurrence of bile- 

 acids in the urine under physiological conditions do not agree. 

 According to VOGEL and DRAGENDORFF and HONE, traces of bile- 

 acids occur in the urine; according to HOPPE-SEYLER and v. 

 UDRANSZKY, they do not. Pathologically they are present in the 

 urine in hepatogenic icterus, although not always. 



Detection of Bile-acids in the urine. PETTENKOFER'S test gives 

 always the most decisive reaction ; but as it gives similar color re- 

 actions with other bodies, it must be supplemented by the spectro- 

 scopic investigation. The direct test for bile-acids is easy after the 

 addition of traces of bile to a normal urine. But the direct detec- 

 tion in a colored icteric urine is more difficult and gives very mis- 

 leading results; the bile-acid must therefore always be isolated from 

 the urine. This may be done by the following method of HOPPE- 

 SEYLER, which is slightly modified in non-essential points. 



HOPPE-SEYLER'S METHOD. Strongly concentrate the urine, and 

 extract the residue with strong alcohol. The filtrate is freed from 

 alcohol by evaporation and then precipitated by basic lead acetate 

 and ammonia. The washed precipitate is treated with boiling al- 

 cohol, filtered hot, the filtrate treated with a few drops of soda solu- 



