474 PATHOLOGICAL PIGMENTATION 



Poulsen " states that of the 32 known eases of oehronosis (in 1911) 

 in 17 there was alkaptonuria, in 8 carbolic acid dressings had been 

 used for long periods, and in the remaining- 7 cases the cause was not 

 determined. These facts are conclusive evidence of the origin of 

 ochronotic pigment from aromatic radicals, whether these radicals 

 are converted into true melanin or not. The localization of the pig- 

 ment is explained by the demonstration by Gross and Allard,^- that 

 cartilage has a greater affinity than other tissues for homogentisic 

 acid. There are, however, numerous cases of alkaptonuria without 

 ochronosis. The ochronosis described in lower animals is not the 

 same as human ochronosis, affecting the bones rather than the carti- 

 lages (Poulsen), 2^ and being more properly designated by the name 

 osteohemachromatosis (Schmey).^* 



Malarial pigmentation, according to Ewing,^^ may have any one 

 of the following origins : 



(1) Pigment elaborated by the intracellular parasite. (2) Hem- 

 atoidin derived from the remnants of infected red cells. (3) Hem- 

 atoidin or altered hemoglobin deposited in granular or crystalline 

 form from red cells dissolved in the plasma. (4) Bilirubin or uro- 

 bilin granules or crystals. 



Of these, the pigment formed by the parasites has been considered 

 by many as a true melanin, but this cannot be considered as estab- 

 lished, especially as Ewing finds it to have the same relation to 

 solvents as do the blood-pigments. Carbone and Brown ^^ consider 

 the malarial pigment to originate from hematin, with which it agrees 

 in solubility, spectroscopic properties, and in containing iron. 



LIPOCHROME 



In normal plant and animal tissues occur pigments that are either 

 fats or compounds of fat, or substances highly soluble in fats. In 

 animals they occur normally in the corpus luteum, in the epithelium 

 of the seminal vesicles, testicles, and epididymis ; in ganglion-cells, 

 especially in the sympathetic nervous tissue ; in the Kupffer cells of 

 the liver; and in fat tissue. Pathologically, such pigments are found 

 particularly in the muscle-cells in brown atro])hy of the heart, and 

 less abundantly in the epithelium of atrophied livers and kidneys 

 (Lubarsch ^^ and Sehrt ^^). All are characterized by staining by such 

 fat stains as Sudan III and scarlet R, and usually, but not constantly, 



3iMuneh. mod. Wodi.. 1012 (50). .'304. 



32 Arch. e\p. Path. u. Pliarm., 1008 (.^O), .'3S4. 



33 See Tn<rior, Ziofjlor's Boitr.. 1011 (r>l). 100. 



34 Frankfurtor Zoit. Patliol., lOl.S (12), 21S; also Toutsclilaoiuler. Virdiow's 

 Arch., 1014 (217). .-^O.^. 



35 .Tour. Exp. l\To(l.. 1002 (fi), 110. 



30 Jour. Exppr. Med., 1011 (1.3). 200. 

 37 Cent. f. Pathol., 1002 (13). SSI. 



3SVirchow's Ardi., 1004 (177), 24S. S(>o also Afavor et ah. Jmir. plnsiol. ct 

 path. ji<-"n., 1014 (16), 581. 



