358 



PHYSIOLOGICAL CHEMISTRY. 



fied as finely granular and coarsely granular casts. Granular casts, 

 and in particular the finely granular types, occur in the sediment in 

 practically every kidney disorder but are probably especially char- 

 acteristic of the sediment in inflammatory disorders. 



(c) Epithelial Casts. These are casts bearing upon their sur- 

 face epithelial cells from the lining of the uriniferous tubules (Fig. 

 no, p. 356). The basic material of this form of cast may be hya- 

 line or granular in nature. Epithelial casts are particularly abun- 

 dant in the urinary sediment in acute nephritis. 



( d) Blood Casts. Casts of this type may consist of erythrocytes 

 borne upon a hyaline or a fibrinous basis (Fig. in, p. 356). The 

 occurrence of such casts in the urinary sediment denotes renal 

 hemorrhage and they are considered to be especially characteristic 

 of acute diffuse nephritis and acute congestion of the kidney. 



(e) Fatty Casts. Fatty casts may be formed by the deposition 

 of fat globules or crystals of fatty acid upon the surface of a hya- 

 line or granular cast (Fig. 112, p. 357). In order to constitute a 

 true fatty cast the deposited material must cover the greater part of 

 the surface area of the cast. The presence of fatty casts in urinary 

 sediment indicates fatty degeneration of the kidney; such casts are 

 particularly characteristic of subacute and chronic inflammations 

 of the kidney. 



(/) Waxy Casts. These casts possess a basic substance similar 



FIG. 114. 



CYLINDROIDS. (After Peyer.) 



