On opening the abdominal cavity of persons who have died in the collapse of cholera one is struck by the general pink or rose tint of the peritoneal coat of the intestines. It is produced by a repletion of the minute branches of the portal venous system. Sometimes the color is rendered very dark by the pitchy blood contained in the veins. The surface of the peritoneum, like all the tissues, is singularly dry, and often has a soapy or sticky feel, caused by a layer of albuminous matter, which forms a lather when rubbed between the fingers, and causes the intestinal folds to adhere to one another. If death takes place during the stage of reaction, these appearances are less distinct, and the intestines, which in collapse are usually retracted, are then somewhat distended.
The stomach generally contains a thin, partially transparent liquid of a greenish or grayish color, and occasionally reddish, holding in suspension portions of coagulated mucus and an unctuous substance of an albuminous nature, which adheres to the walls of the cavity. Fatty globules may be observed floating in the liquid, which under the microscope reveals epithelial débris, granular corpuscles, and fragments of gastric glands. Under heat and nitric acid coagulation of the liquid occurs, and on chemical examination it is found to contain urea. The gastric mucous membrane is of a dark violet or pale pink color, according to the stage of the disease; its follicles are enlarged, and patches of superficial abrasion may be observed on it.
The intestinal canal of those who die during the collapse of cholera is, in the majority of cases, partially filled with liquid which has the aspect of turbid serum, more or less mixed with the previous contents of the bowel if death has taken place very rapidly, but otherwise it is almost colorless. On the whole, however, it is less pale and watery than the stools. It contains, like these discharges, more or less epithelial flocculi, and generally more than were observed during life in the dejections. The mucus scraped from the lining membrane of the intestine and mixed with water renders it turbid with epithelial débris. The same mucus examined microscopically contains fragments, larger or smaller, of epithelium. These conditions are said to predominate in the large intestine. Indeed, the proportion of liquid increases from above downward. Hence in the more prolonged cases the contents of the bowel at its upper part are less liquid and are darker in color. There is, indeed, a striking contrast between the appearance of the intestine in cases which have terminated in collapse and its aspect in persons who have died during the stage of reaction. It has been clearly presented by Dr. Sutton.43 When death took place in "the cold stage the mucous membrane was unusually pale in three cases; in two it was healthy-looking; in other two it was pale throughout, excepting that one or two of Peyer's patches were congested; and in the remaining three there was more or less congestion of the mucous membrane. When the mucous membrane was pale throughout the entire intestine, the valvulæ conniventes looked swollen and oedematous, and the color of the membrane was dead white. The solitary glands were very distinct and prominent. Those of the duodenum were remarkably so. In cases of imperfect reaction the mucous membrane of the intestine was usually found very much congested and ecchymosed. The congested portions were sometimes granular, and apparently denuded of epithelium. The mucous surface had often a dark port-wine color, due to the extravasated blood and the hyperæmia, and here and there the surface was covered with a dirty gray membranous substance, likened to a diphtheritic deposit. I have, however, seen no decided false membrane, such as could be peeled off, as in diphtheria. The surface was also occasionally bile-stained, and the greenish-yellow color of the bile and the deep red color of the congested surface presented a very striking appearance. The solitary glands were very prominent, and in some cases apparently enlarged." The general paleness of the intestinal mucous membrane in the stage of collapse, and its congestive redness whenever the signs of reaction have existed before death, have a very important bearing upon the pathology of this disease, for they demonstrate conclusively that the gastro-intestinal evacuations in cholera have no relation whatever to inflammation. On the other hand, they render it altogether probable that the serous flux is in the nature of a sweat, an intestinal ephidrosis.
43 London Hosp. Clin. Lect. and Reports, iv. 497.
The nature of the exfoliation found in the intestinal canal has been the subject of much discussion. As long ago as the first American epidemic of cholera (1832-35) Dr. W. E. Horner, Professor of Anatomy in the University of Pennsylvania, described an exfoliation of the epithelial lining of the alimentary canal, whereby the extremities of the venous system of the part are denuded, as being characteristic of cholera alone. In 1849, Dr. Samuel Jackson, Professor of the Institutes of Medicine, and Dr. John Neill, Demonstrator of Anatomy in the University, in conjunction with Dr. William Pepper and Dr. Paul B. Goddard, presented a report to the College of Physicians of Philadelphia, in which they, too, showed that the "epithelial layer of the intestinal mucous membrane was either entirely removed or was detached, adhering loosely." This important fact—the most important, perhaps, in the mechanism of cholera—was confirmed seventeen years later by the eminent pathologist Dr. Lionel S. Beale,44 who, when referring to "the remarkable characters of the matter discharged from the intestinal tube, and to the fact that the small intestines almost always contain a considerable quantity of pale almost colorless gruel-, rice-, or cream-like matter," added: "This has been proved to consist almost entirely of columnar epithelium, and in very many cases large flakes can be found, consisting of several uninjured epithelial sheaths of the villi.... In bad cases it is probable that almost every villus, from the pylorus to the ilio-cæcal valve, has been stripped of its epithelial coating during life.... These important organs, the villi, are, in a very bad case, all or nearly all left bare, and a very essential part of what constitutes the absorbing apparatus is completely destroyed.... It is probable that the extent of this process of denudation determines the severity or mildness of the attack.... It seems probable also that the epithelium may become detached in consequence of the almost complete cessation of the circulation in the capillaries beneath, but the death of the cells may occur in consequence of their being exposed to the influence of certain matters in the intestine or in the blood, in which case they would simply fall off."
44 Med. Times and Gazette, Aug., 1866, p. 109.
In this connection, and as complementary of the statements now made, should be considered the further description by the same author—viz.: "Remarkable changes have occurred in the smaller vessels, especially in the capillaries and small veins of the villi and submucous tissue. The blood-corpuscles appear to have in a great measure been destroyed in the smaller vessels, and in their place are seen clots containing blood-coloring matter, minute granules, and small masses of germinal matter evidently undergoing active multiplication. Some of the arteries are contracted, but here and there small clots destitute of blood-corpuscles may be seen at intervals." Hence, the gastro-intestinal lesions in cholera, according to their extent and degree, they remove the natural obstacles to exhalation in the mucous membrane, and also, and in the same degree, prevent the absorption of the contents of the alimentary canal. It must not, however, be forgotten that this lesion is not altogether peculiar to the intestinal mucous membrane. Dr. Beale long ago called attention to the fact that in this disease there seems to be a tendency to the removal of epithelium from the surface of all soft, moist mucous membranes, but not from the follicles of the glands. The first statement appears to be explicable by the shrinkage of all the mucous membranes during cholera collapse, for by this merely mechanical agency the inelastic epithelium must necessarily become detached. As to the second statement, the remark may be made that the whole follicular structure furnished with columnar epithelium is an absorbing and not an eliminating apparatus, and that, since its functional activity is from the beginning of the disease diminished by an inadequate blood-supply, it can have but a small and indirect share in generating the phenomena of the disease.
In 1884, Dr. Koch, during his investigations of cholera in India, found bacilli in the bowel which he believed to be peculiar to the disease, and which presented the following characters: they were not straight, like other bacilli, but curved or comma-shaped; they proliferated rapidly and displayed very active movements. Bodies of persons who died of various other diseases did not present them, although abounding in different bacteria. The bacilli were not found, or only exceptionally, in the stomach, but abundantly in the intestine, and most so in the diarrhoeal discharges that occurred at the height of the disease. As soon as the stools began to be fecal the specific bacilli disappeared from them. After death at the height of the disease they were most abundant in the intestinal contents, and especially in the lower part of the small intestine. When death took place at a later period none of them might be detected in the liquids in the bowel, but they would still be present, in considerable numbers, in the tubular glands. They were not found at all in cases fatal from some sequela of the disease.45
45 Times and Gaz., Mar., 1884, p. 398.
Other abdominal lesions in cholera possess a very subordinate importance. The isolated and the agminated glands are both prominent, chiefly because they are swollen by the liquid imbibed from the bowel. A whitish substance which they sometimes contain may perhaps be the albumen or fat which they have taken from the intestinal liquid. A very similar condition of the mesenteric glands is probably due to a like cause. The liver is pale and flaccid when death takes place in collapse, and it is also described as presenting a "dirty grayish-red, homogeneous appearance, and indistinctness of the lobular structure, as if some glutinous matter had been poured throughout the tissues of the organ" (Sutton). This appearance would seem to be due to the total suspension of the blood-supply through the portal vein.