ATROPHY, DEGENERATION, PIGMENTATION, AND NECROSIS. 81 



To the naked eye, organs in a condition of marked fatty degeneration 

 are usually larger, and softer than normal, have a grayish-yellow color or 

 are mottled with yellowish streaks or patches, and the normal markings 

 of cut surfaces are more or less obscured. 



Fatty degeneration may be associated with or may follow albuminous 

 degeneration and may occur under similar general conditions. It may 





FIG. 16. FATTY DEGENERATION KIDNEY. 

 The fat droplets are stained black by osmic acid. 



be due to local or general disturbances of nutrition, from a great variety 

 of causes ^disturbances~which eitheiFdirectly affect the life processes of 

 the qells themselves, or which produce alterations in their nutritive sup- 

 ply. In addition to its local occurrence, as a result of local disturbances 

 of circulation in the vicinity of inflammations or in tumors, etc., it is 

 apt to occur in the liver, heart muscle, and kidney in chronic exhausting 

 diseases and in conditions ana diseases to which profound^ ansemia is in- 

 cident, or as the result of the action of certain poisons, suclTas phos- 

 phorus and arsenic. 



FATTY INFILTRATION. 



This is of common occurrence under normal as well as pathological 

 conditions. The fat is believed to originate outside of the cells, accumu- 

 lating in them, and inducing a pass- 

 ive atrophy of the cytoplasm. Cells 

 in a condition of abnormal fatty 

 infiltration are scarcely to be distin- 

 guished morphologically from those 

 involved in fatty degeneration. The 

 l>i vscnce in the cells of large or small 

 droplets of fat without marks of de- 

 generation in the remaining proto- 

 plasm has been regarded as distinct- 

 ive of infiltration (Fig. 17). 



In some phases of fatty infiltra- 

 tion, as in the heart (Fig. i>'W)or the 

 pancreas, for example, the fat accu, **' 17 - FATTY * T '* ' 



, . . ,, . r- . . . , In two of the cells the nucleus is crowded to one 



Qiulates 111 the Cells Of the interstitial slde by the accumulated fat 



6 



