Four years ago (1858), Dr. Eiselt of Prague called attention to the fact that in cases of melanotic cancer of the liver, melanine appears in the renal secretion.20 When the urine is passed it is usually quite clear; but after standing it becomes of a dark colour, even as dark as porter, without, however, losing its transparency. This deepening of the colour is no doubt due to the oxidation of the melanotic pigment, as the employment of an oxidizing agent, such as nitric or chromic acid, causes the same change to occur instantly.
20 Dr. Eiselt states that he also found melanine in the urine in a case of melanotic cancer of the eyeball.
In addition to the cases related by Dr. Eiselt, I am able to add one of considerable importance, as it not only offers a striking illustration of the correctness of his views, but has the double advantage of being an unbiassed record of facts, in consequence of its having been observed, and recorded long before Dr. Eiselt's views were published, and therefore at a time when the author had no idea of its significance. The case occurred about thirteen years ago, in the wards of the Royal Infirmary of Edinburgh. The history of the case I extract from my private note-book. It is briefly as follows:—In the month of May a sailor was admitted into the clinical wards of the Royal Infirmary with symptoms of jaundice from enlarged liver. He stated that he had been a great deal abroad, in hot climates, and admitted that he had been a hard drinker. On admission his skin was of a dusky yellow colour, and had been so since the month of February. The liver was considerably enlarged, and he complained of sudden violent pains in the neighbourhood of the umbilicus. The pain was usually most severe during the night. The urine was of a dark colour, and on the addition of nitric acid, became nearly quite black. It contained no albumen. The patient died ten days after admission. On post-mortem examination, the hepatic duct was found blocked up with malignant deposit, and the liver of a dark green colour. There was also a considerable amount of malignant deposit in the mesentery. This patient, as frequently happens in such cases, became delirious before death.
In jaundice arising from melanotic cancer of the liver, the recognition of the presence of melanine in the urine would be an important aid to the diagnosis. Care must be taken not to confound the dark olive-green urine occasionally met with in other forms of jaundice, with the melanotic urine just described, or both patient and doctor may become unnecessarily alarmed.21
21 While I was Resident Physician in the Royal Infirmary of Edinburgh, in 1850, a woman, aged 28, was admitted with a universal and bright jaundice of three weeks' standing. Her urine was high coloured, and of a specific gravity of 1022. It contained a small quantity of albumen, and became perfectly black on being boiled with nitric acid. In this case there was no reason to suspect malignant disease of the liver; the colour of the urine was, therefore, most probably due to the bile pigment being more than usually oxidized. After a six weeks' stay in the hospital, I dismissed the patient as cured.
Urea, Uric Acid, and Sugar.
The presence, and quantity of certain other substances met with in the urine of jaundice, although not peculiar to that condition, nevertheless afford us important information, not only as to its cause, but also as to its probable mode of termination.
Firstly, a correct knowledge of the quantity of urea, and of uric acid passed in the twenty-four hours is of great value; and, secondly, the presence, or absence of sugar is a fact which ought never to be lost sight of. The value of this statement, as well as of several of the preceding, will, I think, be better appreciated by giving a short account of a case of obscure disease (where a correct diagnosis, and prognosis could not have been arrived at without the application of the chemical knowledge referred to), than by any mere abstract treatment of the question. I shall, therefore, at once proceed to relate the brief history of the case.
A gentleman, aged fifty, who had been a remarkably healthy man, observed, within eighteen months of his death, that his skin gradually assumed a more and more jaundiced tint without any assignable cause. The stools were clay-coloured, the urine loaded with bile pigment. Soon afterwards, the patient began to lose flesh. The liver became enlarged, and somewhat tender to the touch; the gall-bladder being at the same time so distended that it could be seen, as well as felt, projecting from under the false ribs. As the case resisted the usual remedies, the patient was recommended to try change of air. During his absence from town, he suddenly passed a large quantity of yellow matter by stool (supposed to be bile), and immediately afterwards the fulness in the abdomen disappeared. On the patient's return to town, the gall-bladder could no longer be seen or felt, and it was naturally supposed that it had emptied itself on the occasion referred to. As, notwithstanding this, the jaundice continued, and the health and strength gradually declined, Dr. Prance, under whose care the patient was, sought the assistance of a physician of distinguished reputation in these affections. At this period, however, the entire absence of physical signs beyond the clay-coloured stools, and those directly referrable to the jaundice, rendered it impossible for any decided opinion to be arrived at. The liver had now resumed its natural size, and the only thing detectable was slight tenderness on pressure, with a doubtful fulness in the pancreatic region. These signs, associated as they were with gradually increasing emaciation and debility, led to the suspicion of malignant disease, either in the course of the bile-ducts, or at the head of the pancreas. About this time it was discovered that the patient occasionally passed a considerable amount of a fatty-looking matter by stool—not mixed with the motion, but separate, though upon it. After the passage of this matter, there in general appeared to be a slight improvement in the patient's condition. The substance in question, on cooling, solidified into a firm pale-brown matter, resembling Windsor soap, and not at all unlike some of the biliary products. This led to the idea that it might be composed of the fatty acids of the bile. On one occasion a portion of it was forwarded to me for analysis, and on subjecting it to chemical examination it proved to be, strangely modified fish-oil, the oleine of which had entirely disappeared. In fact, it was nothing but the sparingly soluble fatty acids of cod-liver oil, which had been transformed in the stomach, and from which all the liquid principles had been absorbed. This was considered an important discovery, as it not only negatived the idea of the bile still reaching the intestines, but also proved that the pancreas, as well as the liver, was affected. Having thus learned that the pancreatic juice, as well as the bile, failed to reach the intestines, an effort was made to counteract the pernicious effect on the system caused by the absence of the former secretion, by giving 1½ grains of pancreatine in the form of pill three times a day. During the period that the patient was taking this medicine, the quantity of fat passed by stool was supposed to diminish. No decided improvement in the patient's condition took place, however, and on the 2nd of November the gentleman was brought to me by his medical attendant. At this time the patient was much in the state already described,22 and after a careful physical examination, I failed to elicit any new fact of importance. The hepatic dulness was perfectly natural; there was no tenderness to speak of, no history of gall-stones, and no evidence of any tumour beyond the doubtful fulness in the pancreatic region. The digestive, and other functions of the body, except those already mentioned, seemed unimpaired, and yet the patient's strength daily declined. As physical as well as symptomatical diagnosis proved inadequate to unravel the mystery of this obscure case, and as chemical means had already, in as far as it had been tried, been of advantage, it was resolved to subject the excretions to a rigid chemical examination. The patient was accordingly desired to collect all the urine he passed during twenty-four hours, and while I analysed it, Dr. Prance examined the stools, in order to ascertain their composition—especially as regarded the amount of fatty and albuminous matters contained in them. The urine yielded on analysis the following result:—