404 DISEASES OF THE URINARY ORGANS. 



There is nothing distinctive of inflammatory processes in 

 the kidneys. As in other organs, though inflammation affect- 

 ing either the parenchyma or interstitial connective tissue 

 alone does not occur, the changes may be so much more con- 

 spicuous in one or the other as to suggest the term parenchy- 

 matous or interstitial inflammation. 



In acute inflammation produced by intense irritants, the 

 glomeruli and epithelium of the secreting tubules are mainly 

 affected ; while in other instances in which the irritant is less 

 intense and acts over a prolonged period, the inflammatory 

 changes predominate in the interstitial connective tissue. 



Casts. 



Casts of the uriniferous tubules have been objects of very 

 considerable interest in connection with these pathological 



FIG. 186. 



a, epithelial casts ; 6, opaque granular casts (from a case of acute Bright's disease ; 



Roberts). 



changes since 1842, when attention was first directed to them 

 by Henle. They are found in the urine, and in the urinif- 



