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.
Lesions. The mucosa of the pancreatic ducts is reddened, congested and thickened and their lumen blocked by a white, granular matter, containing pus globules, fibrine filaments, and granular, ciliated epithelium. The blocked ducts become dilated, and their walls thickened, the epithelium is desquamated to a greater or less extent, and the raw exposed surface may present ulcers or granulations. The pancreatic cells undergo fatty degeneration and the connective tissue becomes steadily indurated (sclerosis). These lesions were especially noted by Megnin and Nocard in a case of pancreatitis in the horse.
In the horse, sheep and goat, which have a common outlet for the bile and pancreatic juice, the blocking of the latter and the arrest of the bile almost of necessity causes hepatitis, and infection in the one gland is directly transferred to the other so that pancreatitis and hepatitis are mutually causative of each other. In the ox, pig, dog and cat, in which the bile and pancreatic juice are poured into the duodenum through separate ducts and orifices, this mutual pathogenic action is not so certain.
When the liver is implicated, there is catarrh and dilatation of the bile ducts, fatty degeneration commencing in the centre of the acini, pigmentation appearing at their periphery, and sclerosis of the organ follows.
Symptoms. In Nocard’s equine case there was progressive loss of spirit, energy, and endurance; appetite was poor and eating listless; after two weeks jaundice set in, the visible mucosæ and skin showing a yellow tinge, and the scanty urine becoming brownish yellow; the bowels became costive the fæces being formed of small hard discolored balls, but no excess of fatty matter is recorded. Emaciation advanced rapidly, the most marked wasting being in the muscles of the back, loins and croup. Death ensued at the end of two months from the commencement of the illness. In man sudden, violent colic, with nausea, tympany and collapse are prominent symptoms.