Anatomical Changes. Syniijtonis. 507 



of acute infectious diseases, severe inflammation of the lungs, 

 and liemoglobinemia arising from unknown causes, was at one 

 time termed hematogenous jaundice. Recent investigations 

 have shown that the bile pigments in these cases also are pro- 

 duced by the liver. 



It is not definitely settled whether in individual cases of hepatitis accompanied 

 hj jaundice the diseased liver cells do not pass a proportion of the bile direct into 

 the blood capillaries (paracholia, parapedesis). 



Anatomical Changes. With the exception of the nerve tissue 

 all the organs are stained yellow as a result of the absorption of 

 bile pigments. This is most marked in tissues that contain fat, 

 such as the mesentery, the fat capsule of the kidneys, subepi- 

 cardial fat and subcutaneous connective tissue. It may, how- 

 ever, also be observed in blood clots, in any fluid exudates that 

 may be present, and in the muscular tissue. (Riither states that 

 in birds affected with jaundice there may be a greenish pigmen- 

 tation of the peritoneum.) 



In the horse the fat is always yellow. In other animals it is also more or 

 less yellow under certain conditions of diet and even when the animals are fed 

 on certain pastures. In emaciated animals the subcutaneous connective tissue is 

 sometimes saturated at places with yellow serum. The sinuiltaneous yellow dis- 

 coloration of all the tissues renders the diagnosis of jaundice easy. 



Symptoms. A characteristic feature of jaundice is the yel- 

 low coloration of the mucous meml)ranes and of the unpigmented 

 parts of the skin. This is recognizable in the earliest stages in 

 the scleral and palpebral portions of the conjunctivae. It is less 

 distinct in the nnicous memliranes of the mouth and nose, unless 

 one causes a temporary anemia of the membrane by exerting 

 pressure upon it. The color varies with the severity and dura- 

 tion of the disease from a lemon- to an orange-, or even a green- 

 ish yellow tint. Unpigmented parts of the skin appear, as a 

 rule, rather more intensely stained. 



The condition may be recognized still earlier by an examina- 

 tion of the urine which is either orange-, brownish-, or greenish- 

 yellow in color, and if agitated gives a yellow froth. White fil- 

 ter paper, linen or silk are stained by the urine. Chemical tests 

 show the presence of bile pigments and often also of bile acids, 

 while microscopic examination of the sediment reveals the pres- 

 ence of masses of pigment which give the bilirubin reaction. 



Gmelin's test is one of the best for the chemical demonstration of the presence 

 of bile pigments. In this test the suspected urine is added to some nitric acid con- 

 taining a few drops of nitrous acid so that it forms a layer al)ove it. A positive result 

 is indicated by a play of colors where the liquids meet, green being the most character- 

 istic. Eosenbach's modification of this test appears to be a practical one. A piece of 

 filter paper moistened with the urine, or better still the paper through which the 

 urine has been filtered, is placed upon a white porcelain slab and is touched with a 

 glass rod that has been dipped in fuming nitric acid. If Idle pigments are present 

 a ring of colors appears around the spot where the acid has been placed. These 

 colors from within outwards are yellow, violet, lirown, green. In some cases only 

 the gi-een color is obtained. 



