26 Archiv für path. Anat., Band xiv. p. 333.
When any large quantity of bile is contained in the urine, its detection is not difficult. A strip of muslin dipped in the urine will be stained, and the underclothing of the patient will have the yellowish spots caused by bile. Gmelin's test is the most convenient. This is applied as follows: Some nitric acid containing nitrous—which is the case of the ordinary commercial article—is put into a test-tube, and some of the suspected urine is allowed to trickle down the side of the tube to come in contact, but not mix, with the acid. At the point of contact, when the urine contains bile-pigment, first a zone of green, then blue, violet, and finally red color, develops. As this play of colors takes place on the instant, the attention must be sharply fixed to see the changes. Rosenbach27 suggests this test be applied by filtering some urine containing bile through filtering-paper and touching the paper with a drop of nitric acid. The result is, a green circle forms at the point of contact. The usual mode of applying Gmelin's test is to place on the bottom of a common white plate or on a porcelain dish a thin film of the urine, and carefully bring in contact with it a thin film of nitric acid. The color reaction mentioned above takes place at the margin of contact.
27 Centralblatt für die medicin Wissenschaft, 1876, p. 5.
Besides the presence of bile and albumen, and some fatty epithelium from the tubules, there is no material change in the composition of the urine. At one time it was supposed that the amount of urea was greatly lessened, but later and more accurate investigations have shown that this excretion is in greater or less quantity according to the food taken, and bears no relation to the jaundice. On the other hand, Genevoix28 maintains that the quantity of urea is increased in spasmodic icterus, and in the same ratio the uric acid declines. As regards the chlorides and other salts, there seems to be a tolerably constant ratio in their variations with the changes of quantity of urea and uric acid—are therefore nearly related to the amount of food taken.
28 Essai sur les Variations de l'Urée et de l'Acide urique dans les Maladies du Foie, Paris, 1876, p. 59 et seq.
As regards the condition of the liver, there is no apparent change. In topography, in the area of hepatic dulness, and in the dimensions of the right hypochondrium the local condition does not deviate from the normal in simple jaundice. There may be more or less tenderness over the epigastrium and along the inferior margin of the liver, but there is rarely any actual pain.
The circulation of bile in the blood and the action of the bile acids on the red corpuscles must have an influence on the functions of various organs. In some cases of jaundice, but by no means in all, the pulse is slow, in a few instances descending as low as 40 per minute, and, according to Frerichs,29 as low as 21 per minute. Usually, the pulse-rate is not lower than 60. To observe the slowing of the heart the patient must be recumbent, for the pulse rises to the normal or above on assuming the erect posture and moving about. The occurrence of fever also prevents the depression of the circulation. The slowing of the heart is found to be due to the action of the bile acids on the cardiac ganglia. The other elements of the bile were ascertained to have no influence on the circulation. As the heart may be slowed by an increase of inhibition through stimulation of the vagi or by a paralyzing action on the cardiac muscle, it was necessary to eliminate these effects to establish the influence of the bile acids on the ganglia. By exclusion, and by ascertaining the effects of the bile acids on a properly prepared Stannius heart, Steiner and Legg have succeeded in demonstrating this important point.30
29 Diseases of the Liver, Syd. Soc. ed., supra.
30 Archiv f. Anat. u. Physiol., 1874, p. 474; Legg, On the Bile, etc., loc. cit.
The temperature of jaundice is normal usually, sometimes below. When a febrile affection occurs during the course of jaundice, the rise of temperature belonging to it is prevented in considerable part, sometimes entirely. The depression of temperature is referred by Legg to the lessened activity of the hepatic functions; but it seems to the writer more satisfactory to refer it to the action of the bile acids on the red corpuscles, the conveyors of oxygen. Röhrig31 has shown experimentally that the injection of bile acids has this effect on the temperature of animals.