ATROPHY OF THE KIDNEY. 



Result of hyperplasia of connective tissues and compression and absorp- 

 tion of parenchyma. Unilateral or partial. Causes : chronic productive in- 

 flammation, calculus in tubes, ureter, or pelvis, tumor, retention cyst, em- 

 bolism. Lesions : sclerosis of kidney, firmness, pallor, anaemia, lack of 

 glomeruli and tubules, cysts, congenital, urinous retention, colloid. Symp- 

 toms : reduced secretion, palpation of kidney. Treatment : Prevention : 

 arrest conditions, abundance of water, succulent food, parasiticides, opera- 

 tion on cysts, counteract nephritis. 



Unlike hypertrophy, this is constantly the result of a patho- ; 

 logical process. So long as a normal functional activity of the 

 secreting elements is carried on, such parts must maintain their 

 size and healthy characters. But with the compression of such 

 secreting elements (glomeruli and convoluted tubes) by a hyper- 

 plasia of connective tissue, by pressure from without or from the 

 damming back of the urine in the pelvis and tubes, the secretory 

 elements are absorbed and removed, and the final result is a 

 general atrophy. If such atrophy appears in both kidneys at 

 once it can only be very partial in extent, as extreme atrophy of 

 both, with loss of their secretory function, would entail poisoning 

 and death from the retained urinary products. The comparative 

 frequency of the disease may be inferred from the reports of the 

 numbers of specimens found by Barrier and Moussu in old horses 

 in the dissecting rooms. The latter observed a dozen cases in a 

 single winter, other examples are recorded by Cadeac (horse), 

 Soula (swine) and Trasbot (in various animals). 



Causes. The most common source of the condition is the 

 occurrence of chronic productive inflammation. The new 

 product in such cases, if not pus, or a growth that rapidly passes 

 into fatty or granular degeneration, or into gangrene, tends to 

 form tissue of a low organization, especially fibrous. The re- 

 sulting increase of the fibrous trabeculse, in undergoing subse- 

 quent contraction necessarilyjcompresses the secretory tissue and 

 the final result is a visible and, it may be, extreme wasting. 

 Hence any slowly advancing productive inflammation is liable 

 to result in absorption and removal of the kidney parenchyma, 

 and distinct atrophy of the gland. 

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