34 2 THE URINE 



III. Calcium oxalate. Octahedral crystals or dumb-bell shapes which are 

 highly refractile. Often due to diet (asparagus, tomatoes, spinach, rhubarb, etc.). 



IV. Cystin occurs in six-sided crystals which are soluble in ammonia. 

 In a urine of alkaline reaction we may expect: 



I. Triple phosphates (NH 4 MgPO 4 ). Usually in coffin-lid or fern-like form. 

 Easily soluble in acetic acid. 



II. Calcium phosphate and calcium carbonate which effervesce on the addition 

 of acid. 



III. Ammonium urate. These show as the thorn-apple structures. 



The presence of ammonium urate, particularly if with triple phosphates, denotes 

 bacterial decomposition within the genito-urinary tract provided the urine is just 



i 



FIG. 103. Fatty and waxy casts, a, Fatty casts; b, waxy casts. 



(Greene.) 



passed. Pus cells derived from the site of inflammation should be present also. 

 While certain bacteria might possibly bring on chemical changes without giving rise 

 to inflammation yet such a possibility is so rare as to be negligible. In the presence 

 of amorphous phosphates one should always think of exogenous sources as vegetable 

 diet or withdrawal of proteid food before thinking of disordered metabolism. 



Organized Sediment. An occasional leukocyte may be found in the urine of 

 healthy people. Any abundance of leukocytes indicates inflammation of genito- 

 urinary tract. Some workers count the pus cells in urine by the same technic used 

 for the leukocyte count of the blood. A urine having 100,000 pus cells per c.mm. 

 will give as a result about 0.1% albumin. 



Leukocytes are found in abundance at times in the urine of women without 



