524 



EXCRETION 



Unorganized Sediments (continued} 



IN ACID URINE. 



solve and uric acid cystals appear 

 in their place. Acid urate of 

 sodium and of ammonium occa- 

 sionally found in the crystalline 

 form (rosettes of needles) . 



Calcium Oxalate. Octahedral, 

 ' envelope ' crystals, not coloured. 

 Insoluble in acetic acid. Soluble 

 in hydrochloric acid (Fig. 178, 

 p. 472). 



Cystin. Hexagonal plates. 

 Rire (Fig. i8o,p. 473). 



Leucin and Tyrosin (Figs. 186, 

 187, p. 483). Rare. Also found 

 in alkaline urine, but rarely. 



Triple Phosphate. Sometimes 

 found in weakly acid urine. 



IN ALKALINE URINE. 



Calcium Phosphate, Ca 3 (PO 4 ) 2 . 

 Amorphous. 



Magnesium Phosphate. Long 

 rhombic tablets, which are dis- 

 solved at the edges by ammonium 

 carbonate solution, unlike triple 

 phosphate. All the above are 

 soluble in acetic acid without 

 effervescence. 



Calcium Carbonate. Small 

 spherical or dumb - bell - shaped 

 bodies soluble in acetic acid with 

 effervescence. 



Ammonium Urate. Dark balls, 

 often covered with spines. Soluble 

 in acetic or hydrochloric acid, 

 with formation of uric acid crys- 

 tals (Fig. 182, p. 473). 



4. Specific gravity. 



5. Quantity of urine in twenty-four hours. If the quantity is 

 abnormally large and the specific gravity high, test for sugar. 



6. Inorganic constituents not generally of clinical importance, but 

 in special diseases they should be examined e.g., chlorides in pneu- 

 monia. 



7. Normal organic constituents. Sometimes quantitative estima- 

 tion of urea or total nitrogen in fever, and in diabetes and Bright's 

 disease. 



8. Chemical examination for abnormal organic constituents, especi- 

 ally albumin and sugar. 



Albumin. (i) Heat to boiling some of the urine in a test-tube. A 

 precipitate insoluble on addition of a f -w drops of acetic acid consists 

 of coagulable protein. A precipitate soluble in acetic acid consists of 

 earthy phosphates. 



(2) Heller's test. Put some strong nitric acid in a test-tube and 

 run on to it some urine. A white ring indicates protein. 



A quantitative estimation may be made by the method of Roberts 

 and Stolnikow or Esbach (p. 517). 



Sugar. (i) Trommer's test. (Fehling's solution may be used.) If 

 the result is indecisive 



(2) Phenyl-hydrazine test (p. 518). 



(3) In case of doubt confirm by yeast test. 



A quantitative estimation may be made with Fehling's solution or 

 the polarimeter. 



