344 RETROGRESSIVE PROCESSES 



inorganic part of the bones and the connective and elastic tis- 

 sues remain three to twelve months. (4) Migration of neutral 

 fat, crystallization and partial saponification of the higher fatty 

 acids in the panniculus ; transformation of the blood pigment 

 into crystalline form four to twelve or more months. 



LIPEMIA 



Normally the blood contains a considerable amount of fat, 

 varying somewhat, but not greatly, with the diet. Engelhardt L 

 found in eight healthy persons an average of 0.194 per cent., 

 with a maximum of 0.237 per cent., and a minimum of 0.101 

 per cent. ; in five cachectic patients the quantities were quite 

 the same. Rumpf, 2 in a large number of morbid conditions, how- 

 ever, found the solid substance of the blood to contain an aver- 

 age of 0.452 per cent, of fat, but with variations between 0.035 

 per cent, and 2.20 per cent. It is, therefore, extremely diffi- 

 cult to say just when the amount of fat in the blood is large 

 enough to be considered as a lipemia. B. Fischer 3 states that 

 we may speak of a pathological lipemia when we have a distinctly 

 cloudy blood or serum, which is clarified by shaking with ether, 

 through the dissolving out of fat which can then be separated 

 from the ether. Earlier writers described, incorrectly, lipemia 

 in many conditions, but recent writers mention it chiefly as 

 occurring in alcoholism and diabetes. By far the greatest amounts 

 of fat are observed in the latter condition. Neisser and Der- 

 lin 4 found 19.7 per cent, of fat in the blood of a patient with 

 diabetic coma (after death 24.4 per cent, was found) whose 

 urine contained 0.8 per cent, of fat, and through analysis of this 

 and other material came to the conclusion that the fat comes 

 directly from the chyle ; i. e., that it is food fat, not body fat. 

 Fischer found an average of 18.129 per cent, in his case, includ- 

 ing at least 0.478 per cent, of cholesterin, with no lipuria and 

 very small amounts of fatty acids ; of the fat, about 67.5 per 

 cent, was olein. 



It is an important question whether, with such high quanti- 

 ties of fat in the blood, fat embolism may result, for it is pos- 

 sible that at least some of the cases of diabetic coma are due to 

 such fat embolism in the cerebral vessels. Ebstein 5 considers 

 this a possible, but not a common, occurrence, because the drop- 

 lets are too small to cause occlusion of the vessels unless they 



1 Deut. Arch.klin. Med., 1901 (70), 182. 



2 Virchow's Arch., 1903 (174), 163. 



3 Virchow's Arch., 1903 (172), 30. Kesume' and complete literature. 

 4 Zeit. klin. Med., 1904 (51), 428. 



5 Virchow's Arch., 1899 (155), 571. 



