Part 80

CATARRHAL ICTERUS (JAUNDICE) OF SOLIPEDS.

Causes: infection from duodenum through biliary duct. Suppression of bile favors. Musty, heated, mow burnt fodder, over feeding, irregular feeding, or watering, over work, worms, fatigue, damp stables, duodenal congestion, gall-stones, concretions, pancreatic tumor, ascaris in bile ducts, distoma, infection through portal vein, toxins. Symptoms: of duodenal catarrh, icterus, yellow, viscous, odorous urine, dullness, weakness, somnolence, tardy pulse and breathing, costiveness, or diarrhœa, pale, fœtid stools. Duration: 2 to 3 weeks or longer. Lesions: duodenitis, distended biliary and pancreatic ducts, calculi, enlarged softened liver and kidneys. Diagnosis: icteric symptoms in absence of fever. Prognosis: usually favorable. Treatment: laxative diet, pasture, soiling, ensilage, roots, fruits, water freely, exercise, antisepsis, elimination, laxatives, cholagogues, diuretics, calomel, salines, nitro-muriatic acid, podophyllin, castor oil, aloes, tartar emetic, bitters, sodium bicarbonate.

Causes. This may be said to be an extension of infection from the duodenum through the bile ducts. The microbes of the intestinal canal become acclimatized by living in the bile-charged contents of the duodenum until they acquired the power of survival and multiplication in the biliary ducts themselves. The well known antiseptic qualities of the bile, constitute a powerful barrier to this, yet the power of adaptation on the part of certain germs is greater than the defensive action of the bile. The attack is however mostly in connection with indigestion or muco-enteritis, and a more or less perfect suspension of biliary secretion, so that this defensive action is reduced to its minimum and the germs can ascend the bile ducts in the mucous secretion as a culture medium, and by interference with the resumption of a free hepatic secretion, they succeed in safely colonizing themselves in the mucosa and hepatic parenchyma. Whatever, therefore, interferes with the integrity of the duodenal functions directly contributes to the extension of infection from bowel to liver. Old, heated, musty, cryptogamic, dusty fodder, grains that have been badly harvested in wet seasons, feed that has been damp and fermented, overloading of the stomach, irregular feeding and watering, giving drink after a feed of grain, underfeeding, overwork, worms, excessive fatigue, damp, dark stables, etc., tend to induce indigestions and to lay the bile ducts open to infection. Blocking of the bile duct and stasis of its contents may be a sufficient cause. The swollen mucosa around the orifice of the duct not only blocks the passage but favors the formation of a mucous plug as recorded by Benjamin of an equine patient. Wolff found obstruction of the duodenum in the horse by a mass of ingesta, and blocking of the gall duct, with jaundice.

Gall stones and concretions are very direct causes of biliary obstruction and jaundice. Though less common in horses than cattle, these are not unknown in idle, pampered animals when on dry winter feeding.

Tumors of the pancreas or adjacent organs pressing on the gall duct are recognized as causes of equine icterus, (Megnin, Nocard).

With any obstruction to the bile a disturbance of balance of pressure between the bile ducts and the hepatic veins is brought about by respiratory movements. On the one hand the aspiratory power of the chest empties the hepatic veins, lessening blood pressure, and in expiration the contraction of diaphragm and abdominal muscles compresses the gall ducts increasing their tension and favoring absorption of bile.

The entrance into the bile duct of the ascaris megalocephala is at once a cause of obstruction and of the transference of duodenal microbes, and the presence of trematodes (fasciola hepatica, or distoma lanceolatum) will also favor obstruction. Other parasites, like the echinococcus or actinomycosis, may press on the biliary ducts and determine jaundice.

Another mode of infection is by way of the portal vein, the microbes entering from the intestine and becoming arrested and colonized in the liver (Dieckerhoff).

Whether from the presence of the microbes or from the absorption of ptomaines and toxins from the intestines, the radical biliary ducts become inflamed, swollen, and even blocked, and the hepatic cells degenerated or even completely devitalized, so that they fail to take an aniline stain. In such cases the remaining sound hepatic cells go on producing bile, but as this cannot any longer escape through the partially obstructed interlobular biliary radicles, it is largely absorbed and produces icterus. Cadeac mentions a case of this kind in a mare in which the toxic matters had not only led to hepatic disease, but also to structural changes in the eliminating organ (the kidney).

Symptoms. In the horse the disease is mostly attendant on subacute duodenitis, and even when this is associated with infective catarrh of the biliary passages the kidneys remain mostly sound and active, and eliminate alike the bile pigments and the more toxic matters so that the disease is not often grave. Beside the essential feature of yellow mucosæ, and urine, the latter viscous and smelling strongly, there is profound depression, sluggishness, weakness and somnolence. Imperfect muscular control and even slight paresis may be present. Tardy pulse and breathing are at times noticeable. At others these, like the temperature, are normal. The mouth is hot and dry. The urine may be slightly albuminous. The bowels incline to costiveness from lack of their customary stimulus, yet this in turn may give rise to diarrhœa. In either case, as the disease advances, the defecations lose the healthy yellowish brown color, becoming pale and fœtid.

Duration. The attack may last one, two or three weeks, and generally ends in recovery. With irremediable structural lesions, it is of course permanent and even fatal.

Lesions. The most common feature is duodenitis with thickening around the orifice of the common bile and pancreatic duct. The biliary ducts may be distended and their contents more than usually viscid and glairy from the presence of pus. Their mucosa may show ramified redness, or concretions as casts or calculi. The liver is enlarged, soft and friable giving way readily under the pressure of the finger. Enlargement of the kidneys is usually present, the cortical substance having a brownish red and the medullary portion a yellowish pink hue.

Diagnosis. The absence of hyperthermia in jaundice, serves to distinguish it from the acute febrile affections (pneumonia, influenza, contagious pneumonia, petechial fever, etc.,) which are marked by yellowness of the mucosæ and skin.

Prognosis. The merely functional forms of icterus in solipeds usually end in recovery.

Treatment. The first consideration is a laxative diet. A run at pasture will usually meet every indication. Fresh cut grass, ensilage, turnips, carrots, potatoes, beet, apples, or other succulent diet may be given as substitute. Bran mashes and hay cut and moistened may be allowed in the absence of the above. Abundance of water and especially cool water will stimulate bowels, liver and kidneys, favor the elimination of the bile by contraction of the biliary ducts, and hasten the expulsion of the poisons through the kidneys. Regular exercise an hour after meals stimulates both bowels and liver to action.

Medicinal treatment is largely directed to antisepsis of the bowels and the arrest of the production of injurious toxins; elimination from the bowels and incidental depletion from the portal vein and liver; antisepsis and stimulation of the liver; and stimulation of the urinary secretion.

The preparations of mercury fill several of these indications. Calomel 2 drs., or blue mass 1½ dr., is not only a soothing laxative and antiseptic, but seems to operate as a calmative and antiseptic to the liver as well. It may be continued in 5 to 10 grain doses two or three times a day, according to the size of the animal and the condition of the bowels, and associated with ½ dr. belladonna extract to each dose together with a bitter (quassia, gentian, nux vomica). Or 4 or 5 ozs. sulphate of soda may be given three times a day, with 2 drs. salicylate of soda as an antiseptic. Or, to increase the hepatic action, nitro-muriatic acid largely diluted may be given in sixty drop doses thrice a day in the drinking water. These are especially valuable for their antiseptic action, cutting off at once the source of nervous irritation from the attendant indigestions, and duodenal congestion, and arresting the flow of the irritant toxins and other products through the portal system. Podophyllin, castor oil, aloes, rhubarb, often act well by depletion from the portal vein, and expulsion of indigestible and irritant matters from the intestines, but there is more danger of resulting swelling of the duodenal mucosa than with the mercurials or aqua regia. Goubaux recommends 2½ drs. of tartar emetic.

Siedamgrotzky has had good results from an electric current sent through the region of the liver, but in the horse this is rarely demanded.

A course of bitters, with bicarbonate of soda in small doses, may be demanded to re-establish the healthy tone of the stomach and intestines, and a run at pasture, or at least an open air life, exercise, and a laxative diet with abundance of good water should be secured. Any undue costiveness should be counteracted at once by a saline laxative.

CATARRHAL ICTERUS (JAUNDICE) IN DOGS.

Pampered artificial life of dogs as predisposition. Eating carrion. Chills especially when heated and exhausted. Infection from bowels. Obstruction of gall duct by inflammation, calculi, neoplasms. Catarrhal exudate as a protector of microbes. Toxins from intestines, food or water. Youth, lack of acclimation, mental shock, blocking of bowel, blood effusion in gall bladder, incubation. Symptoms: signs of gastro-enteritis, prostration with invasion of the liver and especially of the kidney. Icteric urine without jaundiced mucosa. Gravity of icterus with suppression of urine. Hypochondriac tenderness, arched back, dullness, irregular bowels, excited circulation and breathing, preliminary fever tends to subside, tympany, colic, trembling. Death in one or two days or more. Lesions: congestion, degeneration, ecchymosis, ulceration of gastro-duodenal mucosa, extending into liver ducts and acini, bile inspissated, liver enlarged, yellowish brown, softened, fatty, shrunken, distorted hepatic cells. Kidneys congested, ecchymosed, cortical part with necrotic foci; lymph glands congested. Diagnosis: by icterus of tissues and urine tests. Prognosis: grave in acute cases, more hopeful in tardy ones. Treatment: antiseptics, cholagogues, salol, salicylates, alkalies, carbonates, tartrates, iodides, laxatives, cold enemata, aloes, electricity, water freely, pilocarpin, strychnia, aqua regia, digitalis, bitters, muriatic acid, convalescent diet.

Causes. The dog is much more subject to jaundice than the horse, and the affection is liable to be much more severe, than in solipeds. He leads a more artificial life, especially in cities, where the lack of open air exercise, and of the facility for attending to nature’s wants, together with an excessive, varied, stimulating diet predisposes him to constipation, indigestion, and disorders of the stomach, bowels and liver. In other cases the devouring of decomposing food and foul water proves a cause of direct microbian infection, and of poisoning by ptomaines and toxins generated out of the body. Exposure manifestly has something to do with the prevalence of canine icterus, which is more common in spring and especially in autumn than at other seasons. In hunting dogs, out of condition, the suddenly induced over-exertion and fatigue, and the succeeding chill in cold air or water, become accessory factors.

It appears to be most commonly the result of the transference of germs from the intestine, either by way of the bile ducts, or with the blood through the portal vein. The first form is usually the sequel of muco-enteritis affecting the duodenum, with swelling of the walls of the common bile and pancreatic duct at its orifice, or from obstruction by gall-stones, concretions, impacted bowels or neoplasms. With the arrest of the biliary flow the intestinal ferments gain an entrance into the common duct and the sac of Vater, finding protection from the antiseptic bile in the resulting catarrhal exudate, and in this way they reach the gall-bladder, the biliary radicles and the acini. With the entrance of bacteria or toxins by the portal vein on the other hand, there is first a troubled condition of the acini and hepatic cells, an over-secretion of thick bile, and blocking of the passages so that little is passed into the intestine, the greater part being absorbed into the hepatic veins. Fermentation microbes in the stomach and intestines, the germs of suppuration and septicæmia, and saprophytic germs from outside the body are held to be causative of icterus. Cadeac lays much stress on the putrefactive germs in water, and traces different attacks to marshes and foul ponds.

As in other infecting diseases, early age has a predisposing influence. The older subject has presumably been already exposed to the microbe and acquired some measure of immunity. Animals coming new to the locality and poison, are equally susceptible with the young. Trasbot found that 14 out of 17 dogs thus attacked were between three and eighteen months.

Leblanc and Trasbot claim mental shock as a cause of icterus in the dog. The disappointment and weariness caused by the master’s absence, the excitement of a fiercely contested fight, and brutal punishment are adduced as cases in point. Abuse of emetics and purgatives, in connection with a pre-existing hepatic or duodenal disorder or as a supposed prophylactic of canine distemper has induced jaundice.

Obstruction of the small intestine has proved a factor, partly by the reflex irritation through the splanchnic nerves, and partly through obstruction to the common bile and pancreatic duct.

Walley records a case of obstruction of the cystic duct by extravasation of blood in the gall bladder.

Icterus not infrequently supervenes during canine distemper in which the early gastric and duodenal irritation becomes an occasion of the extension of the catarrhal infection to the common bile duct. Even apart from this Trasbot has seen the majority of cases ushered in by a gastro-duodenitis. In this connection it is interesting to quote the remark of Pfuhl that 26 out of 27 persons using the foul baths of a given establishment contracted icterus, while the soldiers bathing in another branch of the Elbe entirely escaped.