Part 92

Epithelioma. This has been described by Kitt, Martin, Blanc, Leblanc, Morot, Cadeac, and Besnoit. It appears in masses varying in size from a millet seed up, bulging from the surface of the organ or deeply hidden in its substance, and stained yellow or green with bile. The liver is usually enlarged, amounting to even 34 pounds (Cadeac). The formation commencing in the acini invades all surrounding parts causing compression and atrophy of the liver cells, and the formation of nests of epithelioid cells often with multiple nuclei and nucleoli. Cirrhosis is not uncommon, and fatty and other degenerations. Microbic invasion and necrobiosis are also common.

NEOPLASMS IN THE SHEEP’S LIVER.

Adenoma has been met with by McFadyean, Johne, Kitt and Bollinger. They hung as pediculated tumors from the surface of the liver, and were in part wedged into its substance displacing the hepatic tissue and vessels. In general they consisted of a dense fibrous stroma with cylindroid and biliary cells in great abundance, sometimes arranged in tubular form. Specimens described by Kitt and Bollinger attained to the size of a man’s head and were stained of a deep green color.

Carcinoma. Casper reports a case of hepatic cancer in the sheep secondary to cancer of the mesentery.

NEOPLASMS IN THE DOG’S LIVER.

Lipoma. Trasbot describes two fatty tumors in the liver of a bitch, one of them as large as an infant’s head. It had a yellowish white color, and had taken the place of the proper hepatic tissue.

Malignant Tumors. These are rather common. Sarcomatous masses with round and fusiform cells in a fibrous stroma; encephaloid with a delicate stroma and large alveoli filled with cells, and having a soft brainlike consistency; carcinoma with dense and thick fibrous stroma and nests of cells in comparatively small numbers; and epithelioma with flattened, cylindroid or other epithelial cells in masses often affecting a tubular aggregation, are seen in different cases. Sometimes apparently primary, they can more commonly be traced to pre-existing centres of the same formation on the course of the portal vein or elsewhere.

Symptoms. A gradual wasting and emaciation with a yellowish pallor of the mucous membranes are characteristic. Trasbot gives the excessive atrophy of the temporal and masseter muscles as pathognomonic. Ascites is a usual complication. Enlargement of the liver, as shown by percussion of the right hypochondrium, and, in case of flaccid abdomen, by manipulation, and attendant signs of tenderness are corroborative. Variability or loss of appetite, and vomiting is not uncommon, and in case of primary or secondary deposits in other organs in the abdomen, thorax or elsewhere, the symptoms resulting from functional derangement of such organ may be found. Treatment is hopeless.

CALCAREOUS NODULES AND DEGENERATIONS OF THE LIVER.

Calcified roundish nodules, in groups, under capsule. Mostly in solipeds. Theories of origin: parasites, microbes, emboli, omphalitis, intestinal disease, biliary obstructions. Calcification of liver with large abdominal aneurisms. Cszoker’s case, Diagnosis and specific treatment impossible.

In the domestic animals in general the liver may become the seat of imperfectly spherical nodules of a white, yellow or brownish white color, varying in size from a millet seed to a pea or hazel nut, and of a gritty consistency and feeling, from the deposition of earthy salts. These may be seen in groups under the proper capsule, the adjacent hepatic tissue being healthy, or atrophied, sclerosed or pigmented. These lesions have been found most abundantly in solipeds.

Pathogenesis. The most varied doctrines have been advanced as to the origin of these lesions. They have been attributed to the previous presence in the liver of linguatula, echinococcus, cœnurus, oxyurus, distoma, and other parasites (Cadeac, Mazanti, Olt, Ostertag, Gripp, Leuckart, Ratz), to glanders, to microbian attacks (Dieckerhoff), to minute embolic infarcts in omphalitis in the foal, or intestinal disease in the adult (Kitt), and to obstructions by the eggs of distomata in the biliary ducts (Galli-Vallerio). It is not improbable that the lesion may be due to any one of these in a specific case, and this may be ascertained by the existence of certain definite features and conditions. Linguatula, echinococcus and cœnurus can only be suspected in districts where these prevail, and a careful examination of the central mass of the nodule should reveal the presence of the indestructible hooklets, as certified for given cases by Olt, Ostertag and Gripp. In case of nematoid worms or distomata, the eggs may possibly be found as in the cases of Villach and Ratz, or the embryos (Mazanti). Or there may be traces of channels formerly hollowed out by the worms in the vicinity of the nodules, as seen by Leuckart. Coincident tumors of the intestinal mucosa from larval nematodes, or aneurism or emboli in the anterior mesenteric artery would corroborate this conclusion. If distomata had started the lesions, the distension of the gall ducts and the thickening of their walls would be likely to indicate their former presence. Glander nodules might be suspected from the absence of a distinct rounded or oval outline, from the lack of a distinct, clear line of demarcation between the nodule and the adjacent liver tissue, and by the manifestation in the periphery of the nodule and around it of free cell proliferation, showing the mode of progression by the invasion of new tissue. If still active, the bacilli should be discoverable in stained scrapings or sections. There should also be distinct indications of the lesions of glanders in the lymph glands of the portal fissure, of the mediastinum, of the submaxillary region and of other parts.

Heiss records an interesting case of general calcification of the horse’s liver, with large aneurism of the abdominal aorta, mesenteric and renal arteries. The liver was thirty-two pounds, puckered on the surface and showed calcic degeneration of the walls of the vessels and hepatic tissue, to such an extent that when the organ was dried it did not add materially to its hardness. Microscopically the diseased centres indicated minute blood clots (thrombi), with fibrinous development and cretifaction. The lesions in this case were attributed to multiple emboli in connection with the aneurism. It might suggest further, microbian infection of both the aneurismal and hepatic vessels. In another case of extensive cretifaction of the horse’s liver reported by Cszoker, the calcified masses tended to assume rounded forms like tubercle, and had a clear glistening surface.

These lesions are mainly interesting in a pathological sense, and unless they are very extensive do not give rise to appreciable symptoms.

Treatment could only be prophylactic and directed to the removal of the special conditions, in which the calcification originated in a given locality.

ACTINOMYCOSIS OF THE LIVER.

On damp infested soil, in cattle and swine. Round tumors, hard surface, soft centre, fibrous sac, club-shaped cells in tufts. Symptoms of liver disorder. Coincident external actinomycosis. Treatment: potassium iodide.

In damp soils where actinomyces are present in the soil and vegetation, it is not uncommon to find the characteristic growths in the liver of cattle and swine. Rasmussen saw twenty-two cases of hepatic actinomycosis in one year (1890) and in a number of cases he has found the liver, spleen, peritoneum and intestine simultaneously affected. Jensen who has also recorded hepatic cases, found tumors extending from the liver to the diaphragm. He describes them as rounded masses, of different sizes, enclosed in a fibrous envelope of variable thickness, hard and resistant at the surface and somewhat softened toward the centre. Microscopic examination detects the club-shaped cells arranged in tufts and radiating from a common centre.

Symptoms are only the general indications of hepatic disease differing according to the size, and position of the morbid product and its interference with normal functions. When, however, superficial actinomycosis is found these symptoms may be fairly attributed to the existence of similar products in the liver.

Treatment consists in the administration of potassium iodide in full doses, daily for a week, followed by a laxative, and then, after an interval of two days, repeat the treatment for a second week, and so for a third, fourth and fifth until the microbe has been destroyed.

PARASITES OF THE LIVER.

Lying as it does in the channel of the blood charged with the products of absorption from the intestine, the liver is especially liable to parasites. Among protozoa are: Monocercomonas hepatica (pigeon), saccharomyces guttulatus (rabbit), eimeria falciformis (rabbit), coccidium oviforme (rabbit, pig, dog). Among the lower cryptogams are actinomyces (ox, pig). Of the tapeworm family are: Cysticercus tenuicollis (ruminants, pig), c. pisiformis (rabbit), c. cellulosa (dog, pig), echinococcus veterinorum (animals, man), tænia fimbriata (sheep, deer), and an undetermined cœnurus (cat). Of trematodes are: Distoma hepatica (herbivora, man), distoma lanceolatum (herbivora, man), distoma giganteum, or Americanum (cattle), d. truncatum, d. conjunctum, d. campanulatum (dog), amphistoma explanatum (ox). Of nematodes are: Stephanurus dentatus, ascaris suis, oesophagostoma dentatum (pig), sclerostoma equinum, ascaris megalocephala (horse), ascaris bovis (ox), oesophagostoma columbiana (in ruminants), filaria hepatica, enstrongylus gigas, ascaris marginata (dog), ollulanus tricuspis, ascaris mystax (cat). (See Parasites).

DISEASES OF THE PANCREAS.

Obscure. Shown only by digestion or hepatic disorder. Excess of fat in stools suggests suppression of secretion. Intestinal fermentations. Suspension of glycogenesis and consequent emaciation, stunting or poisoning. Pancreatic calculus and icterus.

Diseases of the pancreas are even more obscure than those of the liver. Situated on the course of the duodenum, beneath the lumbar vertebræ and their right transverse processes, and separated from the lateral walls and floor of the abdomen by the great mass of the intestines, it is not open to manipulation or satisfactory percussion, and its secretions being used up in the function of digestion, so that they cannot be perceived and tested externally like the secretions of the kidneys. Beside the general constitutional disorder therefore, we must look rather to the derangements of the digestive functions, to the abnormal condition of the fæces, and to the alterations in subordinate functions like the glycogenic action of the liver, for indications of an unhealthy state of the pancreas. The suppression of the pancreatic secretion has long been associated with the occurrence of fat in the stools, yet this may result from the lack of bile which has important functions to fulfill in emulsionizing fat, and in securing its endosmosis. On the other hand the lack of pancreatic juice may hinder the complete digestion of the albuminoids, and favor their fermentation and the occurrence of tympanies, congestions, abnormal secretions, etc., which may be easily attributed to another origin. Then again the dependence of the liver on the pancreas for its stimulus to glycogenesis, would suggest a series of disturbances from the abundance of the unused food principles, from the hindrance to nutrition and growth, and perhaps from the toxic action of the hepatic products. Once more, through the common excretory duct, infection of the pancreas may extend to and involve the liver, and blocking of the common duct by pancreatic parasites, or calculi, may stop the flow of bile and cause jaundice or other icteric disorder. And yet, it is rarely the case that pancreatic disorder is successfully diagnosed, and it is too often only at the post mortem examination that the actual lesions are revealed.

CATARRHAL PANCREATITIS.

Probable causation by parasites, calculi, irritants, microbes. Lesions: mucosa reddened, thickened, ducts dilated, epithelium fatty, granular, desquamating, pus, connective tissue indurated. Interdependence of pancreatitis and hepatitis in horse, sheep and goat. Liver lesions. Symptoms: loss of vigor, endurance, appetite, and condition. Icterus, costiveness, fœtid, fatty stools, percussion tenderness—right side. Treatment: antithermics, eliminants, antiseptics, derivatives, alkalies, salicylates, ether.

Causes. We know little of the causes of this affection, but it may be inferred that parasites, calculi and other irritants, will produce in this as in other mucosæ a mucopurulent inflammation. Then again the presence of pus suggests the coöperation of pus microbes as in the infective catarrhal icterus. The blocking of the common gall and pancreatic duct, by gall stones or biliary products, will entail arrest of the discharge of pancreatic juice, and a consequent pancreatitis, just as blocking with pancreatic products will cause hepatitis and icterus.