ACUTE PARENCHYMA TO US NEPHRITIS. 



407 



Waxy casts have a peculiar glistening appearance, which 

 distinguishes them from the hyaline variety. The last two 

 varieties occur in both acute and 

 chronic nephritis (Figs. 186-190). FIG. 190. 



ACUTE PARENCHYMATOUS 

 NEPHRITIS. 



Acute parenchymatous nephritis 

 may be a primary affection, occur- 

 ring often without discoverable cause ; 

 or secondary, as a rather frequent 

 complication of scarlet fever, diph- 

 theria, and other acute infectious 

 diseases, and of pregnancy. 



Clinically, the condition is charac- 

 terized by acute onset, scanty, albu- 

 minous, and often bloody urine, 

 dropsy, and uremia ; the most 

 prominent features are headache, 

 coma, and possibly convulsions, due 

 to retention in the blood of noxious 

 substances, normally eliminated by 

 the kidneys. 



Anatomically, the appearance of 

 the kidney varies considerably, ac- 

 cording to the duration and intensity 

 of the affection. 



Macroscopically, in some instances of acute parenchymatous 

 nephritis, especially where the inflammatory process is limited 

 to the glvmeruli glomerulo-nephritis further than a slight 

 hyperaemia and swelling of the cortex, there may be but 

 little evidence of the changes which have taken place. Gen- 

 erally, however, the organ is enlarged, often to twice its natural 

 size, flabby and friable ; its capsule is tense, gaping widely on 

 being incised, and is easily detached, exposing a perfectly 

 smooth surface. In the early stages the organ may be deeply 

 congested ; but later it is often pale in proportion to the 

 swelling and degenerative changes in the tubular epithelium, 

 and the inflammatory cellular and serous exudations which 

 express the blood from the interlobular vessels. 



Different forms of waxy casts 

 (v. Jaksch). 



