A system of practical medicine. By American authors. Vol. 2

by Unknown

The diarrhoea pancreatica is the least constant of all the objective symptoms; in fact, constipation is present in many pancreatic affections, notably carcinoma. The fecal evacuations in this condition are frequent, thin, viscid, and contain an abundance of leucin. Under the microscope the leucin appears either in the form of concentrically sheathed globules, or as small crystalline rods and scales collected together in the form of wheels or aggregated in clusters. This form of diarrhoea may be attributed to a hypersecretion from the pancreas.

That the presence of fat in the stools is an important diagnostic symptom of pancreatic disease is proved both by clinical and experimental observations. The characters of these stools vary considerably. The fat may appear mixed with the feces in small lumps, ranging in size from a pea to a hazelnut, yellowish-white in color, soluble in æther, and easily melted and burned. Again, after the evacuation has become cool fat may be seen covering the fecal masses, collected into a thick cake around the edges of the containing vessel, or, when the feces are liquid, floating as free oil on the surface. Finally, the fat may be in a crystalline form, the crystals being needle-shaped and aggregated into sheaves and tufts. The quantity of fat also varies. It may be present only in small quantities, or may even be entirely absent from the evacuations in those cases in which the secretion from the pancreas is simply diminished, and the amount is greatest in those instances where there is a simultaneous arrest of the pancreatic and hepatic secretions. It must be remembered, too, that even in health the stools may contain fat; this occurs when an excess of oleaginous food is consumed and after the administration of castor oil or cod-liver oil. These conditions must be eliminated, therefore, in estimating the value of fatty stools as a diagnostic symptom; if, then, at the same time, coincident disease of the liver can be excluded, the symptom becomes almost pathognomonic. The appearance of fat in the stools may be due not only to an arrest of the pancreatic secretion, but also to pressure upon the large lymphatic trunks, interfering with the circulation of the chyle and checking the absorption of fat from the intestine.

Usually, the amount of fat expelled is in direct proportion to the quantity consumed, but occasionally the former greatly exceeds the latter. In such cases there must be some other source for the evacuated fat than the food; and it is probable that fat from the adipose tissue passes into the blood, and thence through the mesenteric vessels into the intestine. This theory would likewise account in part for the rapid and extreme wasting, and for another less frequently observed symptom—namely, lipuria. A case is recorded by Clark of medullary cancer of the pancreas with nutmeg liver, and another by Bowditch of cancer of the pancreas and liver in which lipuria was noted. The fat was observed, after the urine had cooled, floating about on the surface in masses or globules; differing, therefore, from chyluria, for in this condition the fat is present in the form of an emulsion, and gives the urine either a uniform milk-like appearance, or, after it has been allowed to stand, rests upon the surface in a creamy layer.

When the pancreatic secretion is arrested, most of the animal food which has escaped gastric digestion will pass unchanged through the intestine and give rise to another characteristic condition of the evacuations—namely, the presence in the feces of undigested striped muscular fibres. The amount of these fibres, and indeed their appearance at all in any given case, will depend directly upon the nature of the food consumed.

SUBJECTIVE SYMPTOMS.—The subjective symptoms of disease of the pancreas are abnormal sensations in the epigastrium, and pain.

The abnormal sensations in the epigastrium are weight and pressure, attended at times by præcordial oppression and discomfort. The feeling of weight is usually deep-seated, may be intermittent or constant, and is generally increased or developed by pressure. It is often influenced by position, the assumption of the erect posture or turning from side to side giving rise to a stretching or dragging sensation, as if a heavy body were falling downward or moving about in the upper abdomen.

The pain may be due either to an inflammation of the peritoneum covering the gland or to pressure upon the solar plexus, and consequently varies in character. When it depends upon localized peritonitis, it is constant, circumscribed, and deeply seated in the epigastrium at a point midway between the tip of the ensiform cartilage and the umbilicus; it is rather acute, and is greatly augmented by pressure. The second variety occurs in paroxysms, and is neuralgic in character, the sharp, excessively severe lancinating pains extending from the epigastrium through to the back, upward into the thorax, and downward into the abdomen. These paroxysms—in reality attacks of coeliac neuralgia—are attended by great anxiety, restlessness, and oppression and a tendency to syncope. That calculi in the duct of Wirsung, tightly grasped at the position of arrest, may give rise to paroxysms of pain analogous to biliary colic, cannot be doubted, though there are no positive facts in support of this view.

PRESSURE SYMPTOMS.—When the pancreas becomes enlarged it encroaches upon the neighboring blood-vessels and viscera, interferes with their functions, and thus produces prominent symptoms.

The ductus choledochus from its close relation to the head of the gland is especially liable to become obstructed, with the consequent production of chronic jaundice and the general effects of the absence of bile from the intestinal canal. Pressure upon the portal vein gives rise to enlargement of the spleen; on the inferior cava, to oedema of the feet and legs; and on the aorta, occasionally, to aneurismal dilatation of the vessel above the point of obstruction and to subsequent alteration in the size of the heart. By encroaching on the stomach an enlarged pancreas may cause either displacement of the viscus or stenosis at its pyloric extremity, attended with occasional vomiting of large quantities of grumous, fermenting liquid, pain, constipation, general failure of health, and the distinctive physical signs of dilatation of the stomach. The duodenum may also be pressed upon and more or less occluded, and pain and vomiting occur several hours after food is taken. Occasionally hydronephrosis is produced, the accumulation being usually in the right kidney and due to obstruction of the corresponding ureter.

A sufficient number of cases have been collected to show that there is an intimate connection between disease of the pancreas and diabetes mellitus. One or other condition may take the precedence, melituria occurring during the progress of pancreatic disease, demonstrating the onset of diabetes, and the appearance of fatty stools in diabetes a secondary involvement of the pancreas. Various theories have been advanced to account for this association, but the true explanation seems to be based upon the experiments of Munk and Klebs. By experimenting upon dogs these observers found that extirpation of the solar plexus produced either permanent or temporary diabetes, whereas section of the hepatic and splanchnic nerves, removal of the pancreas, or ligature of the duct of Wirsung was without effect. From the intimate anatomical relation of the pancreas to the solar plexus it is easy to understand how disease of the gland may give rise to alterations in the nerve-structure, either by direct pressure or by the extension of inflammation along the nerve-fibres connecting the gland with the ganglia; and these alterations in time produce diabetes. In the instances in which diabetes is the primary affection the condition of the pancreas, as proved by post-mortem section, is usually one of simple or fatty atrophy; and it may be assumed that a lesion of the solar plexus is the cause of both diseases, the changes in the pancreas being produced in a similar way to the atrophy of the submaxillary gland after section of the vaso-motor nerves in Bernard's experiments.