Probably most practitioners who are in the habit of making post-mortem examinations have seen the flakes of lymph in the ascitic fluid, etc., but the German physicians have been the first, I believe, to regard such cases as belonging to separate forms of disease.
William Pepper has published9 a case observed by himself and G. A. Rex which shows non-malignant chronic peritonitis better than any I can recall to mind. The report forms the sequel to the case of the young woman on whom he successfully performed paracentesis of the pericardium.
9 Am. Journ. of Med. Sci., April, 1874.
This young woman began to have double pleuritic effusion, and this was soon followed by ascites three and a half months after the operation. From that time the ascites was better or worse, but did not wholly leave her, and became considerable before her death. This was sudden, she having some convulsive movements in extremis. Lesions were found in the thoracic cavity like those discovered in the abdominal, showing, it was believed, a special tendency in this person to plastic exudation on the serous membranes. "The lower part of the abdomen was found occupied by an extensive effusion. The intestines were floated upward. There were few if any signs of inflammation of the intestinal peritoneum, but marked changes were observed in the parietal peritoneum and in the capsules of the liver and spleen. The peritonitis was most marked in the upper segment of the abdomen, while the parietal membrane presented large patches of irregular thickening. No tubercles were found on any part of the peritoneum. The capsules of the liver and spleen were greatly thickened, whitish, opaque, and densely fibrous. The liver was enlarged and heavy, and so tightly bound by its thickened capsule that its shape was somewhat altered.
"The diaphragm, especially that part of it underlying the pericardial sacs, had undergone marked fibroid degeneration. The muscular tissue was much atrophied; many fasciculi had evidently disappeared, while many others were markedly narrowed, some of them shading off to a width of less than 1/3000 of an inch, and finally disappearing altogether. They retained, however, even in their narrowest dimensions, their transverse striæ."
(It may be remarked, in passing, that this substitution of fibrous for muscular tissue follows the same law that it does in the heart when that organ is the seat of fibrosis or fibrous degeneration. Here it was supposed to be the consequence of a low grade of inflammatory action. Is it when it occurs in the heart?)
In the abdomen these observers found nothing which suggested the possibility of tubercles or any obscure form of cancer. In the pericardium, on the heart side, were found numerous small nodular roughnesses. Irregularities of the pericardial false membrane are so common that nothing but the close and universal adhesions would raise any question of these relations. But tubercles would hardly be here and nowhere else.
Delafield says that one form of the chronic disease is the continuance of his cellular peritonitis. In this, he says, the surface of the omentum is covered with cells which look as if they were derived from the endothelium and connective-tissue cells, although they differ from the normal shape of these. The new cells are for the most part polygonal, of different size, with one or several nuclei, and giant-cells—large granular masses filled with nuclei. Although these new cells are produced over the entire surface of the peritoneum, yet, as a rule, they are more numerous in little patches here and there. These little patches may be heaped together in such numbers as to form nodules visible to the naked eye. There is never any stroma between these cells.
This form of peritonitis occurs most frequently with organic heart disease, with cirrhosis of the liver, with chronic pulmonary phthisis, and with acute general tuberculosis. In the two latter diseases he thinks they have been improperly called tubercles.
He describes a form of chronic adhesion of peritoneal surfaces that occurs without the intervention of fibrin, but, as he supposes, by coalescence of the branching cells and a production from them of a fibrillated basement substance, the fibrils crossing in all directions. In the midst of these fibrils he finds the nuclei of these cells. He finds also in the immediate neighborhood of these adhesions thousands of branching cells that are attached one to another and float free in the water, the fixed end being attached to the peritoneum. He regards such a peritonitis with adhesions as a more advanced stage of the forms of cellular peritonitis already described, and the new cells are changed into membrane.