Acute Nephritis. Acute BrighVs Disease. 225 



acid, and normal in herbivora and carnivora, are increased if the 

 urine is acid as in severe nephritis, but also in rheumatism, te- 

 tanus, septicaemia, angina, heaves, and other affections with de- 

 fective aeration of the blood. 



Ammonio-magnesian phosphate crystals, rhomboid but 

 insoluble in acetic acid, are found in alkaline (ammoniacal) or neu- 

 tral urine, and appear to be often due to intestinal fermentations. 



Cystine crystals, flat hexagonal plates, precipitated in healthy 

 urine, but dissolved by ammonia are absent in retained and fer- 

 mented specimens. 



Uric acid crystals, rhomboids and plaques, brick red, and 

 normal in the urine of carnivora and flesh-fed omnivora, may be 

 present in herbivora not only in acute nephritis, but in other ex- 

 tensive inflammations attended with anorexia and the consump- 

 tion of the animal tissues. 



Hippuric acid crystals, right rhombic prisms and their de- 

 rivatives, and insoluble in hydrochloric acid or ether, are greatly 

 increased in all febrile diseases in herbivora, nephritis included. 



Haematoidin crystals, fine needles or bundles of the same, 

 yellowish red, are found in nephritis, hsematuria, heaves, etc. 



Epithelium, if columnar, points to disease of the kidney 

 tubes, though very similar cells are derived from the urethra in 

 both male and female. Squamous epithelium points to the cystic 

 mucosa and is not increased in nephritis. 



Mucus in cylindroid form may point to nephritic congestion or 

 inflammation, but this may be present in health, and may show 

 in irregular masses derived from the renal pelvis or the bladder. 

 Mucous casts are always extremely elastic and mobile, and lack 

 the even clear cut margins of the casts of nephritis. They are 

 much more common in horse's urine than in that of other animals. 



Tube casts are especially indicative of nephritis and exuda- 

 tion into the uriniferous tubes. They are much firmer than the 

 mucous cylinders and have smoother and more even margins. 

 If relatively thick and straight they probably 'come from the 

 straight tubes ; if sinuous or twisted, from the convoluted tubes. 

 With, a similar basis substance they often enclose different solid 

 bodies and have been named accordingly : — epithelial casts 

 when containing cylindroid, or polyhedral cells may be unhesi- 

 tatingly referred to the uriniferous tubules : — granular casts in 

 15 



