INFLAMMATION OF THE KIDNEYS— NEPHRITIS 389 



tis), or an involvement of both the renal epithelium and the 

 interstitial tissue without the formation of a purulent exudate 

 (nephritis acuta diffusa). 



Etiology.— This disease is quite common in small animals 

 and birds in which it frequently develops from infectious 

 diseases and poisons. 



Acute nephritis occurs secondary to infectious diseases. 

 The organisms circulate via the blood stream, become lodged 

 in the glomeruli and in the intertubular bloodvessels, and 

 at the point of lodgment injure the tissues. In this way the 

 disease occurs during the course of distemper, chicken cholera, 

 septicemia, etc. Bacterial toxins in passing through the 

 cellular elements of the kidneys, produce in them and the 

 bloodvessel walls certain degenerative processes, which 

 eventually lead to an acute inflammation. The bacterial 

 toxins probably produce the disease in the majority of cases, 

 as the absorption of toxins takes place in a number of condi- 

 tions, such as in diseases of the alimentary tract, diseases 

 of the peritoneum, etc., and in this manner we may account 

 for the development of acute nephritis during or following 

 such diseases. In like manner acute nephritis may occur 

 following any organic disease. In small animals it frequently 

 follows the ingestion of decayed foods, the preformed toxins 

 are absorbed and eliminated through the kidneys, producing 

 a severe form of acute nephritis. The same condition may 

 result from absorption of products from wounds, from mange, 

 eczema, etc., especially when extensive. 



Acute nephritis also develops from vegetable and mineral 

 poisons, especially when introduced in rather large quantities. 

 Such substances, as cantharides, carbolic acid, arsenic, oil 

 of turpentine, extract of male fern, mercury preparations, 

 etc., are eliminated via the kidneys and excite an acute inflam- 

 mation. Birds (turkeys) often eat various insects, such as 

 grasshoppers, caterpillars, the acrid substances of which are 

 absorbed from the intestinal tract and induce the inflamma- 

 tion. This same condition has been observed in cats from 

 eating large numbers of insects (grasshoppers). 



Injuries in small animals are very common, such as blows 

 across the back in the region of the kidneys, being run over 



