The quantity of urine is invariably diminished. When the body of the stomach is the seat of disease, and pain is the principal symptom, the daily amount may exceed thirty fluid ounces ; but if the orifices are involved or vomiting is severe, only about fifteen fluid ounces may be voided in the twenty-four hours. Both the colour and the specific gravity are somewhat increased, and if numerous metastases are present in the liver an excess of urobilin may be observed (Tissier). An odour of acetone is often detected during an intercurrent attack of subacute gastritis, and the existence of diacetic acid may be demonstrated by the bloodred colouration which is produced by the addition of perchloride of iron (Jaksch). Oxybutyric acid is also occasionally found (Klemperer). Senator has shown that excessive putrefaction of the intestinal contents, with constipation, may be accompanied by the elimination of indican. A simple test for this substance consists in mixing equal parts of urine and strong hydrochloric acid in a stoppered bottle, and adding one drop of a solution of calcium hypochlorite and one cubic centimetre of chloroform. After shaking for a few minutes the indican is converted into indigo, which produces a deep blue colouration of the fluid.
1 Vide Samuel Fenwick, The Saliva as a Test for Functional Diseases of the Liver, 1887.
Although chronic interstitial nephritis existed in 15 per cent, of our cases, albuminuria was observed in only 3 per cent. A large quantity of albumin is usually indicative of parenchymatous nephritis, infarction, or of secondary growths in the kidney. Peptonuria has been observed by Maixner and Parganowski. By the former it was attributed to a loss of functional activity on the part of the gastric mucous membrane, and by the latter to the production of peptone by the disintegration of the cancerous growth.
The quantity of urea which is excreted varies considerably. During the early stages of the complaint, and in cases that pursue an acute course, the daily output may be increased owing to the rapid wasting of the tissues ; but with the progress of inanition the amount gradually diminishes, until it may average only twenty to twenty-five grammes in the twenty-four hours. The diminution is much greater when the pylorus or the cardiac orifice is obstructed, for in such cases the total may not exceed ten to fifteen grammes. Bommelaere believes that the elimination of less than twelve grammes of urea per diem by a patient who suffers from chronic indigestion is pathognomonic of gastric cancer ; but the researches of Bobin, Kirmisson, and Deschamps have shown that a similar diminution of the salt may accompany non-malignant affections of the stomach. It is permissible, however, to assume that carcinoma does not exist in a case where the daily quantity of urea exceeds thirty grammes.
As a rule the chlorides are greatly diminished, and this fact is regarded by Jaccoud as one of great clinical importance. It is probable, however, that the percentage amount of chlorides in the urine does not depend so much upon the existence of carcinoma as upon the degree of inanition with which it is attended. Thus, Bouveret has observed an excess of these salts when the body of the stomach was affected without obstruction of the orifices, while in cases which suffered from excessive vomiting or extreme dysphagia less than one gramme, was often voided in the course of the twenty-four hours. It may also be noted that in many cases of hypersecretion secondary to chronic ulcer the total quantity of chlorides is reduced to a still smaller figure. An excess of ethereal sulphates is occasionally present when cancer of the pylorus has given rise to great dilatation of the stomach.