I'ATIlOLOalVAL OVCUh'KEXCE OF CHOLKSTEROL 415 



salt, while the neutral fats are stained red by the oxazone base (J. L. 

 Smith). Fischler and Gross"'' state that fatty acids are present in 

 atheromatous areas and about the margin of anemic infarcts, but 

 are not recognizable by this method in such fatty degenerations as 

 ])neuin()nic exudates, caseation, etc. Klotz "^ considers that calcium 

 soaps are formed as the first step in pathological calcitication, accord- 

 ing to microchemical evidence ; but a chemical investigation of the 

 same question did not give tlie writer positive results.^' In fatty 

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

 as fatt\- ac'ds, whirli hre really crystals of neutral fats."' 



PATHOLOGICAL OCCURRENCE OF CHOLESTEROL 's 



Cholesterol in crystals is found under somewhat the same conditions 

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

 hol, its phj'sical properties are so similar that it may be considered 

 in this place. (See "Gall-stones," Chap, xv, for further discvission.) 

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

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

 tion is poor. 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 1.25 per cent, of cholesterol has been found 

 (Ruppert "^). 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 kidne,ys, however, show an 

 increase only in the cholesterol esters, and not at all in the free choles- 

 terol. (See Relation of Lipoids to Fatty Metamorphosis, p. 404.) 

 Ameseder ^^ found that 28.56 per cent, of the ether extract of athero- 

 matous aortas was cholesterol. The claim of Chauffard that arcus 

 senilis, xanthelasma, and other ocular conditions depend on choles- 

 terol deposition is not substantiated by Mawas."* In liquids the crys- 



GiZiegler's Beitr., lOO.l (7th suppl.), 343. 

 G5 Jour. Exp. :\rocl., 100.5 (7), 033. 



66 Wells, Jour. Med. Research, 190G (14). 491. 



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



68 Concerning the chemistry of cholesterol see introductory chapter. 



69 See Bostrocm, Cent. f. Path., 1897 (8), 1. 



69a Southard has described cholesterol concretions up to 2 cm. diameter in the 

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

 ToRiforma Med.. 1909 (25), 67. 

 7iMiinch. med. Woch., 1908 (55), 510. 

 T2Zeit. physiol. Chem., 1910 (67), 174. 

 73Zeit. physiol. Chem., 1911 (70), 458. 

 T4Monatsbl. f. Augenheilk., 1912 (13), 604. 



