J^002 Chronic Indurative Nei^hritis. 



latter affection not infrequently becomes manifest without tlie 

 severe symptoms of the non-inclurative inflammation having 

 been observed; moreover, atrophic kidne}^ is sometimes discov- 

 ered accidentally in animals which had always been healthy. 



In regard to the primary atrophic kidney there is nnich to 

 indicate that causes primarily similar to those in the chronic non- 

 indurative inflammation are active (see page 99(3), but with 

 this difference that they manifest their injurious influence less 

 intensely Init for a longer time. There is also a possibility that 

 after an acute nephritis has run its course, a slowly progressive 

 increase of the renal connective tissue commences. This would 

 explain those cases in animals where the sjmiptoms of indur- 

 ative nephritis become manifest a certain time after recovery 

 from some infectious disease. Frohner observed a case of 

 chronic nephritis which formed a sequel of paralytic hemoglo- 

 binemia. Haase found a sequel of swine erysipelas in the kid- 

 neys of hogs to have taken the form of isolated connective tissue 

 foci containing few erysipelas bacilli. 



In carnivorous animals the action of toxins must be consid- 

 ered which develop from the food-stuffs rich in albumins, during 

 digestive disturbances or in chronic skin diseases (ecy.ema, 

 mange) ; and in such cases confinement in dark yards is said to 

 exert a predisposing influence. In birds the fact that the uric 

 acid is formed in great quantities might have an unfavor- 

 able action, as is made strikingly evident in gout. Joest found 

 chronic nephritis in a cow with urinary calculi of xantliin and 

 with deposits of xanthin in the kidneys. 



The influence of chemical poisons may be concluded from 

 the occurrence of the disease in animals which have eaten sour 

 plants on wet pastures, and in such cases chronic liepatitis 

 usually develops at the same time (Vol. II). Such an action of 

 chemical poisons is proved also by the ex])eriments in Avhicii it 

 was possible to produce a chronic nephritis by tlie systematic 

 administration of small amounts of lead- and copper-salts (El- 

 lenberger & Hofmeister, Heubel & Meyer, Trasbot). 



A primary affection of the arteries only rarely is respon- 

 sible for the production of chronic nephritis. In isolated in- 

 stances the disease w^as observed in aortic aneurism (Gadeac, 

 Marek) or in degeneration of the renal artery (Lustig), and in 

 such cases the arrestment of small blood clots may contribute in 

 producing the chronic inflammatory process. In dogs an indu- 

 rative nephritis is sometimes found simultaneously witli valvu- 

 lar troubles, though probably not as a conse(|uence of the heart 

 lesion itself, but owing to the same cause which has given rise 

 to the chronic endocarditis. On the other hand, repeated em))o- 

 lisms in the kidneys may also cause a process of atropliy (em- 

 bolic atrophic kidney). 



Mechanical irritation may produce chronic interstitial 

 nepliritis in the presence of urinary calculi or of worms in the 

 renal pelvis. The same etfect may probably be produced also 



