INAUGURAL DISSERTATION.

THOUGHTS ON MALARIAL POISON FROM A PHYSIOLOGICAL STANDPOINT.

W. T. SMITH, M.D, ROAN, LA.

Prefatory to the following the writer wishes to state that he is fully aware of the disposition on the part of the medical profession to sit down on theory, and hopes that what is not admissible in teachers may be allowed in the student. The province of human knowledge is merely to observe facts and trace out their relations and sequences. This is to be accomplished by a careful and extensive observation of facts as they go before us, and by carefully distinguishing their true relations from connections which are only incidental and temporary. There is a fondness for generalizing in medical science which may lead to error of a practical nature. This error consists in assuming a fact as general, which is not true of all individual cases.

All medical teachers agree that the various types of our endemic fevers have a cause in common; that they are produced by the same identical poison. For practical purposes this view is as near the truth as necessary, but from a physiological and scientific standpoint it cannot be true. The The very basis of our therapeutics is the fact that all medicines have their own peculiar effect in all individuals. There are a few exceptions to this law which we call peculiar idiosyncrasy of temperament or constitution. "That the same cause will produce the same effect" is a law which I think holds equally good in toxicological investigations. Malarial poison should be no exception to this law, nor is it when properly studied and understood. How, then, are we to harmonize this law with the accepted opinion that a certain poison when introduced into the system of one man will produce an intermittent, in a second a remittent, and in a third a pernicious or continued type of fever? It cannot be admitted that alteration of quantity of the poison exercises the sole influence in determining the type of fever.

Most probably it depends on the character of poison imbibed. The late loved Prof. Bemiss saw the impossibility of one poison

producing effects so dissimilar, and used the following language: "That in the present state of medical knowledge it is not at all possible to explain why different epidemics of malarial diseases should give rise to such a diversity of phenomena, so that one epidemic will be characterized by a peculiar train of symptoms which will be absent in another." It can only be explained by the hypothesis that there exist as many different forms of malarial germs as there are different forms of malarial fevers. In the present state of our medical knowledge it is impossible to demonstrate the chemical or microscopical differences in malarial germs; so the only way to judge as to the truth of this hypothesis is to study closely the effect of malarial poison in man.

By their botanical affinities plants of the same genus yield medical products which have very similar effects. So marsh emanations yield vegetable organisms which belong to the same species, and when introduced into the system produce diseases which belong to the same class, but yet are not identical, one form of spores or bacilli producing the intermittents, another form producing the remittents, still another the continued fevers. Dropping now this theory, let us investigate for the present the physiological action of malarial poison.

The first perceptible effect of the poison when introduced into the system is a stimulating effect on the sympathetic and vaso-motor system, particularly the fibers which are distributed to the liver, spleen, and the cutaneous periphery. Consequently we have loss of temperature and contraction of arterioles and venules, with accumulation of blood in the great vascular organs, the liver, spleen and kidneys. At the same time there is stimulation of the function of these organs. Bile is secreted and poured out in large quantities, while in the spleen red blood corpuscles are destroyed in large quantities. The poison up to this point has only produced an increase of normal action, a pure hyperemia. The poison continuing to act, the sensibility of the vaso-motor fibers is destroyed, with paralysis of their motor terminal filaments. This brings forward the second stage in the malarial disease— influx of blood to the periphery and rise in temperature; the liver ceases to perform its function, and we have the hot stage.

It is very evident that if the paralysis remains for days or weeks we would have a continued form of fever. Fortunately this is rare, and there is a strong disposition on the part of the nervous system to regain its lost equilibrium.

The influence of the poison, having spent its force, also passes away in a few hours, but will reassert its influence in the usual cycle if not prevented by proper treatment. Should the poison be peculiarly virulent, not only the vaso-motor system, but the reflex activity of the cord, is partly paralyzed, which is evinced by the loss of muscular power. The respiratory centers are depressed and finally paralyzed; in fatal cases there is stupor, coma and dilated pupils. By those who live in malarious districts the poison is imbibed almost constantly, and produces a peculiar cachexia which is well known to Southern practitioners.

This pathological condition is brought about by the constant stimulation of the liver and spleen; this constant hyperæmia results in hypertrophy of these organs. Their blood vessels will be found enormously enlarged. With this condition should the cumulative action of the poison exert itself by a sudden outbreak of the disease, it would be easy to understand the remarkable and dangerous condition which would follow. During the chill, the blood having accumulated in these enlarged vessels and being in a state of stasis, the most dangerous and serious blood lesions occur.

By chemical action, which physiological chemistry has as yet failed to explain, red blood corpuscles are destroyed in immense numbers, with deposition of pigment. These pigmentary bodies are carried on by the general circulation and deposited in various organs, or produce embolism. Should the kidneys be the seat of hyperæmia, and the uriniferous: tubes denuded of their epithelial lining, with the increased blood pressure, we have that condition known as malarial hematuria. In this connection it will be found that these blood lesions are the principal factors in those desperate cases which are the "bete noire" of the Southern practitioner"swamp fever."

In the treatment of these cases their pathology should be kept constantly in view. We should remember we are deal

ing with a blood lesion which amounts to traumatism. Of course we cannot cure this condition with quinine, as in ordinary malarial fevers, but by the use of quinine we can prevent the recurrence of the paroxysm, which in these cases is everything.

DIARRHEA OF CHILDREN.

J. H. SHOAF, M.D., BURLISON, TENN.

Of this disease we have several varieties, with modifications of symptoms and appearance in the character of the evacuations. In mild cases the stools look very much like those the result of the action of a purgative. Sometimes the actions have a putty-like appearance; in some instances the discharges consist mostly of viseid mucus, occasionally streaked with a little blood; in others the evacuations have a whitish or milky appearance, and contain more or less casein, accompanied with rapid retrograde metamorphosis of tissue and prostration. This modification of the disease is called cholera infantum by some physicians. The latter is a disease of sudden onset, characterized by the so-called rice-water evacuations, which leave but a mere stain on the napkin and is of but a few days' duration, and mostly confined to towns and large cities. We have still another form of gastro-intestinal catarrh, in which there is a mixture of feculent matter, mucus and undigested articles of diet-lienteric. In this modification of the disease the abdomen is generally tumid and tense, and the body and extremities greatly emaciated. This form, however, is really but little more than a severe form of indigestion, symptomatic of great irritation and sensibility of the intestinal mucous tissue.

Nausea and vomiting are common in all forms or modifications of the disease, except mild cases. Each of the modifications in the character and appearance of the evacuations. essentially depends on a peculiar pathological condition of the gastro-intestinal tract, which it is of great importance to recognize before adopting treatment.

The causes of the disease in question are very various: crude and indigestible articles of diet, dentition, and bad sanitary surroundings; but high atmospheric heat I believe

to be the greatest factor in the production of bowel complaints. in children. Its tendency to derange the functions of the liver is well known. The occurrence of bowel diseases in children is unquestionably more frequent during the hot summer months than in the colder seasons of the year. It is probable, however, that the agency of solar heat in the production of diarrhoeal diseases depends more on the miasmatic exhalations which it generates than on its direct operation on the animal functions, for it is beyond question that bowel diseases are much more frequent and pertinacious in low and malarious districts than in more elevated portions of country. That high atmospheric heat by its own direct influence on the animal system is capable of producing bowel diseases can hardly be doubted.

In the treatment of this disease attention to the diet is of primary importance. Crude and indigestible articles of food must be rigidly avoided. If the child is still at the breast no change of course is necessary, unless the milk is depraved. Cow's milk, diluted one-half with water, forms a very good article of diet; rice, if well boiled, is also a very good food. All articles of diet, let them be ever so bland, should be given in small quantities. If more food is given than the stomach is able to digest, the remainder will pass down the alimentary tract in an undigested state, and act as an irritant on the already too sensitive mucous membrane, and keep up the inordinate discharges. If the skin be dry and inactive the tepid bath will do good.

As to medicinal treatment in mild cases probably brought on by errors in diet, where an aperient is indicated, a mixture of equal parts of castor oil and aromatic syrup of rhubarb forms a very good remedy for this purpose. When the liver is engorged and not acting well I generally give hyd. chl. mite with pulv. ipecacuanha every three or four hours, until that organ is restored to healthy action. When there is a good deal of gastro-intestinal irritation, with profuse and exhausting discharges, astringents are called for. For this purpose aromatic sulphuric acid, combined with deodorized tincture of opium, acts very well. But when these sort of things obtain, oxide of zinc and sub. nit. bismuth are my favorite remedies. They act by allaying the irritability of the terminal filaments.