490 PATHOLOGICAL PIGMENTATION 



ous icterus there occur occlusions or lesions of some sort in the bile 

 capillaries, which can account for the reabsorption of the bile into the 

 general circulation. ^^^ Therefore, it was beheved that the pigments 

 that produce the general discoloration of icterus are, at least for the 

 most part, manufactured by the liver, whatever the cause of the re- 

 absorption of the bile from the Hver into the blood may be. That 

 hemolytic agents cause icterus was explained by the fact that on 

 account of the large amounts of free hemoglobin brought to the liver, 

 excessive amounts of bile-pigments are formed, which render the bile 

 so viscid that it blocks up the fine bile capillaries; on account of the low 

 pressure at which bile is secreted, a slight obstruction of this kind is 

 sufficient to stop entirely the outflow of bile, which then enters the 

 capillaries of the liver and also, to a less extent, the lymphatics.-^ It 

 is also possible that the hemolytic poisons injure the liver-cells so 

 much that the minute intra- and intercellular bile capillaries become 

 disorganized, and permit of escape of bile into the lymph-spaces and 

 its absorption into the blood-vessels. ^^ Swelling of the degenerated 

 liver-cells may also be an important factor in the occlusion of the bile 

 capillaries; swelHng of the lining cells of the bile capillaries may also 

 coexist, and fibrin may occlude them in toxic or infectious icterus. 



However, Whipple and Hooper-^ have obtained experimental evi- 

 dence that after intravenous injection of hemoglobin into dogs with 

 the liver excluded from the circulation, bile pigments appear in the 

 urine and icterus is manifested in the fat tissues, from which observa- 

 tions it is concluded that the Hver may not be the only place in which 

 bile pigment can be formed from hemoglobin.''" Several authors have 

 found bilirubin produced in hemorrhagic effusions located where the 

 liver could have had no influence. ^^ We also recognize tj'pes of hemo- 

 lytic icterus in which the liver does not seem to be concerned, and 

 with bile pigments present in the blood and urine unaccompanied by 

 bile salts (dissociated icterus), so that the old dictum of the essential 

 implication of the liver in icterus seems to be incorrect.-'-' Joanno- 

 vics^'' gives, as a result of a comparative study of icterus from bile 

 obstruction and icterus from hemolysis, the following chief differ- 



2« See Eppingcr, Ziegler's Beitr., 1903 (33), 123; Gerhardt, Miiuch. incd. Woch., 

 1905 (52), 889. Lang (Zeit. exp. Path. ii. Ther., July, 190G (3), 473) has demon- 

 strated the presence of fibrinogen in the bile in i)hosph()rus-poisoning, which 

 perhaps accounts for the "bile thrombi" ol)servod l)y Kppinger in toxic icterus. 



" See Mendel and Underbill, Amer. Jour. Phj^sioL, 1905 (14), 252; Whipple 

 and King, Jour. Exp. Med., 1911 (13), 115. 



28 Sterling, Arch. exp. Path., 1911 ((U), 468; Fiessinger, Jour. Physiol, et 

 Pathol., 1910 (12), 958. Oertel (Arch. Int. Med., 191S (21), 73) suggests (hat 

 intracellular preciintation of bile pigment within liver cells altered by poisons may 

 prevent its excretion into the bile canaliculi. 



-'■Mour. Exi)er. Med., 1913 (17), 593 and 012. 



'" Attempts to i)roduce bile pigments from hemoglobin by bacterial action 

 have been unsuccessful. (()uadri, Fol. Clin. Chim., 1914, No. 10.) 



=" Hooper and \Vhipi)le, Jour. Kx]). Med., 191() (23), 137. 



'■>- See Leiu'liiic, Ikntr. i)atli. Anat., 1917 ((14), 55. 



'•■' Zeit. f. llcilk.. Path. Abt., 1904 (25), 25. 



