GLANDS. 473 



"Cystic degeneration of the kidneys, dilatation of the pelvis and ureters 

 (Hydronephrose, Rayer), &c., also give rise to great increase of size and 

 weight. 



''Diminution of Size and Weight: Atrophy. This condition sometimes 

 occurs to a certain extent, in emaciated subjects, without any disor- 

 ganisation, owing to the diminished activity of secretion. More fre- 

 quently, however, it is the result of separation of the epithelium, followed 

 by contraction and obliteration of the tubular structure. 



" Atrophy, from this cause, is liable to supervene in all other varieties 

 of renal lesion, except the waxy degeneration, which appears to lead to 

 a permanently hypertrophied condition of the organ. In kidneys en- 

 larged from exudation, the occurrence of desquamation and its conse- 

 quences is frequent ; and the diminution of size in such cases is often 

 not followed by a return to the natural condition, but by permanent 

 atrophy. 



" The course of all disorganising diseases of the kidney is to produce 

 first, enlargement, and then contraction of the organ. In the extreme 

 stages of the atrophy which results from exudation, exudation is often 

 nearly absent. When exudation, therefore, even in very sparing 

 quantity, accompanies a contracted condition of the kidney, there is a 

 probability that it has been abundant at some former period. 



" Irregularities of Surface : Tuberculated and Granulated Kidneys. 

 The smoothness of the surface in the kidney is destroyed either by un- 

 equal dilatation or unequal contraction of the tubuli of the cortical 

 substance. The former takes place in the waxy degeneration ; the latter, 

 in the desquamative processes. 



" The most frequent irregularities of surface are formed in connection 

 with the granulations of Bright. These are invariably formed when 

 exudation is deposited in kidneys tending to the desquamative lesion ; 

 and, as this runs its usual course, the granulations become prominent 

 from the destruction of the tubes around them. An extreme degree of 

 the irregularities thus produced constitutes the tuberculated kidney. 



" The puckering and partial atrophy occasionally seen in kidneys, other- 

 wise not morbid, or comparatively slightly diseased, are probably, in 

 many instances, the result of the obliteration of cysts. 



" The more remarkable changes in colour and consistence are described 

 very fully in many parts of the preceding memoir." 



On reviewing the whole of the preceding observations, Dr. Gairdner is 

 induced to regard the following conclusions as especially important in 

 relation to the pathology of renal diseases : 



" 1 . By far the greater part of the pathological lesions of the kidney 

 arise from, or are connected with, the exudation of oleo- albuminous 

 granules into the interior of the tubes and epithelial cells. 



" 2. The oleo-albuminous exudation is, probably, often preceded, and, 

 certainly, occasionally accompanied, by vascular congestion ; but when 

 the quantity of exudation is considerable, more or less complete depletion 



