rATIIOLoaiCAL OCCURRENCE OF CHOLESTEROL 419 



soaps are forinod as the fiist step in pathological calcification, accord- 

 ing to microchciuical evidence; but a chemical investigation of the 

 same question did not give the writer positive results.'-" In fatty 

 cells, especially in the liver, crystals are often found and interpreted 

 as fatty acids, which are really crystals of neutral fats."^ 



Pathological Occurrence of Cholesterol" 



Cholesterol in crj^stals is found under somewhat the same conditions 

 as the fatty acids, and although cholesterol is not a fat, but an alco- 

 hol, its ph3^sical properties are so similar that it may be considered 

 in this place. (See "Gall-stones," Chap, xvii, for further discussion.) 

 The characteristic large flat plates of cholesterol may be found in any 

 tissue in which cells are undergoing slow destruction, and where absorp- 

 tion is Y>oor. Therefore, they are found frequently in atheromatous 

 patches in the blood-vessels, encapsulated caseous areas, old infarcts 

 and hematomas, inspissated pus-collections, dermoid cysts, hydrocele 

 fluids, etc.; especially large amounts occur in the cholesteatomatous 

 tumors of the ear and cranial cavity. ^^ 



In degenerative conditions of the central nervous system^^ choles- 

 terol may be present in the spinal fluid (Pighini''^), and in an old 

 pleural effusion as much as 3 to 4 per cent, of cholesterol has been found^ 

 (See Pleural Effusions, Chap, xiv.) Windaus- found that normal aortas 

 contain about 0.15 per cent, cholesterol, while in two atheromatous 

 aortas he found 1.8 per cent, and 1.4 per cent., the increase being 

 more in the cholesterol esters than in the free cholesterol. Amyloid 

 kidneys, however, show an increase only in the cholesterol esters, and 

 not at all in the free cholesterol. (See Relation of Lipoids to Fatty 

 Metamorphosis, p. 406.) Ameseder^ found that 28.56 per cent, of 

 the ether extract of atheromatous aortas was cholesterol. Tlie claim 

 of Chauffard that arcus senilis, xanthelasma, and other ocular condi- 

 tions depend on cholesterol deposition is not substantiated by Mawas'* 

 but Verse^^ observed corneal opacity in rabbits fed cholesterol and oil. 

 In liquids the crystals form glistening scales; in fresh tissues they may 

 be recognized by their solubility in ether, cholorform, hot alcohol, 

 etc., and by their color reactions. In histological specimens prepared 

 by the usual methods the cholesterol is dissolved out, but the resulting 

 clear-cut clefts are quite characteristic. In fresh specimens in which 



9* Wells, Jour. Med. Research, 1906 (14), 491. 

 95 Smith and White, Jour. Path, and Bact., 1907 (12), 126. 

 9^ Concerning the chemistry of cholesterol see introductory chapter. 

 9^ See Bostroem, Cent. f. Path., 1897 (8j, 1. 



'^ Southard has described cholesterol concretions up to 2 cm. diameter in the 

 brain and cord. (Jour. Amer. Med. Assoc, 1905 (45), 1731.) 

 99 Riforma Med., 1909 (25), 67. 



1 Ruppert, Miinch. med. Woch., 1908 (55), 510; Zunz, Hedstrom, and others 

 (see Chap. XIV). 



2 Zeit. physiol. Chem., 1910 (67), 174. 

 ^Zeit. physiol. Chem., 1911 (70), 458. 



* Monatsbl. f. Augenheilk., 1912 (13), 604. 



