990 Acute Nephritis. 



plague, and in septicemias in general. However, in the majority 

 of cases the bacterial toxins exert an immediate pathogenic 

 action upon the kidneys. In passing through the cellular ele- 

 ments of the kidneys they produce, in them and in the vessel 

 walls, degenerative processes and subsequently an inflammation 

 of the kidneys. The various toxins do not, apparently, exert 

 a like action in this respect, but this much may be maintained 

 in general that the development of nephritis is to be anticipated 

 the more surely, the more intense the infection has been. This 

 is the explanation of the development of nephritis in those 

 cases in which no bacteria circulate in the blood and in which 

 they cannot later be shown in the renal tissue, but where other 

 symptoms of intoxication, especially fever, permit the suspicion 

 that toxins are present in the blood; this is especially the 

 case in influenza of horses, purpura, distemper, tetanus, foot- 

 and-mouth disease. 



In similar manner every extensive inflammation of the 

 gastro-intestinal canal and of the peritoneum may give rise 

 to a nephritis. As a matter of fact every extensive organic 

 inflammation may, under certain conditions, also supply the 

 impetus for the development of nephritis. Finally infectious 

 substances and their toxins are of etiological importance also 

 in that form of nephritis which sometimes develops after the 

 ingestion of spoiled food-stuffs. 



The kidneys are likewise irritated by hemoglobin which 

 happens to be in solution in the blood plasma, a fact which 

 explains why in severe cases of hemoglobinemia also a de- 

 generation or an extensive necrosis of the epithelial cells 

 (Johne) develops, or even a true nephritis. In such cases, 

 in addition to the blood coloring matter, the agencies upon 

 which the hemoglobinemia is based or certain products of dis- 

 integration are probably of essential importance. It is evi- 

 dently in the same manner that nephritis occurs after extensive 

 burns of the skin. 



The nephritis which occurs not infrequently accom- 

 panying certain skin diseases (eczema, mange) probably owes 

 its origin to the injurious action of toxic substances which 

 are formed in the inflamed skin, but which are not known 

 exactly. 



Anatomical Changes. The anatomical changes are either 

 easily recognizable to the naked eye or can only be demon- 

 strated by microscopical examination. According to Kitt, who 

 was the first to attempt a systematic classification of inflam- 

 mations of the kidneys on a histological basis, the following 

 clinical pictures belong to the group of acute nephritis. 



Nephritis Parenchymatosa Acuta (cloudy swelling, edematous, 

 albuminous degeneration of the kidneys). The disease is essentially 

 an affection of the epithelia of glomeruli and tubuli uriniferi, it is 



