Chapter XLVIII: Front Matter (48)

The gravity of the so-called lotura carnea, the fleshy stools, was fully appreciated by Hippocrates, as is evidenced by the remark that "if in a person ill of dysentery substances resembling flesh be discharged from the bowels, it is a mortal symptom." Fleshy masses, [Greek: xysmata], scrapings of the guts (originally epidermic exfoliations from the bodies of gladiators, used in pills as a tonic), were frequently alluded to by the older writers, more especially by Aretæus, in description of the discharges of dysentery. Hippocrates was also aware of the fact that dysentery may be a secondary as well as a primary malady. "One may expect," he says in speaking of the victims of gangrene, "that such patients will be attacked with dysentery; for dysentery usually supervenes in cases of mortification and of hemorrhage from wounds." Finally, Hippocrates recognized the effects of emesis in relief of the disease with the remark in one of his aphorisms that a spontaneous vomiting cures dysentery.

Celsus (25 B.C.-45 A.D.), the great encyclopædist, whose works "constitute the greatest literary monument since the days of Hippocrates," compiles all the information obtained up to his time; but it is plain as regards dysentery, though he defines it in terms that might stand in a modern text-book, that he has nothing new to add to the knowledge of the Hippocratic school. He named the disease from one of its most prominent symptoms, tormina (tenesmus he considered a separate affection), speaks of the stools as being mixed with mucus and fleshy masses, and in its treatment especially enjoins rest, "as all motion proves injurious to the ulcer."

Aretæus (50 A.D.), of all the authors of antiquity, wrote the most perfect and at the same time the most picturesque account of the morbid anatomy and symptomatology of this disease. The gross appearance of the ulcers in the intestine and the common character of the discharges he {779} describes with the accuracy of the modern pathologist and the ardor of the true clinician. He speaks of the superficial, the deep-seated, the irritable, and the callous ulcer. There is, he says, "another larger species of ulcers, with thick edges, rough, unequal, callous, as we would call a knot of wood; these are difficult to cure, for they do not readily cicatrize, and the cicatrices are easily dissolved." Their tendency to arrest and renewal and their general and local effects he notices at length. "There may be a postponement of their spreading for a long time," he says, "various changes taking place in the ulcers, some subsiding and others swelling up like waves in the sea. Such is the course of the ulcers; but if nature stand out and the physician co-operate, the spreading may indeed be stopped, and a fatal termination is not apprehended, but the intestines remain hard and callous, and the recovery of such cases is protracted." Vivid descriptions he gives of the stools: "Sometimes they are like chopped tallow, sometimes merely mucus, prurient, small, round, pungent, causing frequent dejections and a desire not without a pleasurable sensation, but with very scanty evacuations." Again, they are "fetid like a mortification;" composed of "food now undigested, as if only masticated by voracious teeth, ... the dejection being discharged with much flatulence and noise; it has the appearance of being larger than its actual amount."

Galen (164 A.D.) attempted to correct the pathology of his contemporaries, who considered all bloody discharges dysenteric. There are four distinct varieties of bloody stools, he claims, only one of which, that due to ulceration of the intestine, deserves to be called dysentery. The bilious stool he derived from melancholy, and the fleshy stool from disease of the liver. But, though Galen regarded the presence of blood as a necessity, he was well aware of the fact that the stools contained ingredients other than blood. It was Galen who first used the word scybala ([Greek: schybala], feces) to express the small, solid masses of excrementitious matter often voided with the stools. In his treatment of the disease he made much use of the various drying earths, the Samian, Lemnian, Armenian, the sources of which he made long journeys to visit in order to become better acquainted with their properties, and which are better substituted in our day by bismuth, chalk, magnesia, and the carbonate of iron. It is the distinguished merit of Galen to have called special attention to the anatomical seat of the disease. Ulceration of the intestine he claimed as the very essence of the disease, and all the physicians of his day, he maintained, regarded as dysenteric only such cases as are attended with ulceration.

Galen was the exponent of the flower of Grecian, we might say of ancient, medicine. With very few exceptions, the later writers, if they do not obscure the original text with their speculations, are content to simply paraphrase the observations of their predecessors, and the subsequent contributions to the ancient history of dysentery may be briefly summed up in a few additional notes.

Coelius Aurelianus (400 A.D.) adopted the humoralistic doctrine of Hippocrates and regarded dysentery as an intestinal rheumatism (catarrh) with ulceration. He seems to have been the first author to recognize the cardinal fact that dysentery, notwithstanding the number of its stools, should be classed with the diseases which constipate the bowels, or, as it {780} was centuries later aptly put by Stoll, "ut hanc morbis adnumeres alvum potius occludentibus," and he blames Erasistratus for using nothing but astringents, whereas many cases of dysentery require laxatives. It is worthy of note that Coelius Aurelianus ascribes the first use of opium in the treatment of dysentery to Diocles of Carystus (300 B.C.), who administered the juice of poppies combined with galls. By the time of Galen opium was so freely used in the treatment of the fluxes as to call for protest against its abuse.

Alexander of Tralles (575 A.D.) is often credited as having been the first to locate the disease in the large intestine. The truth is, he suggested various rules by which the seat of the disease, whether in the small or large intestine, might be definitely determined. But none of these rules--the seat of the pain, for instance, whether above or below the umbilicus, and the interval of time between the pain and discharges, whether long or short--possess the least diagnostic value or add to the attempts in this direction of previous writers--Aretæus, Archigenes, and Galen. Like these, his predecessors, he recognized an hepatic dysentery with discharges of bloody serum, which he attributed with them to atony of the liver, but more boldly than they, and with characteristic independence, he ventured to treat his patients with fresh vegetables and fruits, damsons and grapes.

Paul of Ægina (660 A.D.) locates the disease in the rectum, and gives a graphic account of its symptomatology. He made the mistake of many later practitioners in regarding as a separate disease a symptom, tenesmus, which he describes as an irresistible desire of evacuation, "discharging nothing but some bloody humor, which is the cause of the whole complaint, being an oedematous inflammation of the rectum which creates the impression of feces lodged in the intestine and a desire of evacuation." "Dysentery," he continues, "is an ulceration of the intestines, sometimes arising from the translation of tenesmus, and sometimes being of itself the primary affection; and is attended with evacuations at first bilious and of various colors, then accordingly bloody, and at last ichorous, like that which runs from dead bodies."

In curious contrast to these accurate observations is the absurd suggestion of an obsolete therapy (Galen), that the dried dung of dogs who had eaten bones, when drank in milk which has been curdled by having heated pebbles put into it, is of great service; but as an offset to this freak of fantasy is the renewed advocacy of warm milk, fallen somewhat into disuse since the days of Hippocrates and Galen: "And milk itself moderately boiled is an excellent thing"--a recommendation of the milk diet which now plays such an important rôle in the treatment of so many diseases of the alimentary canal.

Modern.--From this brief survey it is seen that the writers of antiquity left nothing in the symptomatology of dysentery for subsequent authors to describe. All further advance in our knowledge of this, as of all diseases, was now rendered impossible by the extinction of the light of science in the long night of the Middle Ages, whose gloom deepens with succeeding centuries and whose shadows fall close up to our own times.

The modern history of dysentery may be said to begin with Daniel Sennertus, whose first _Tractatus de Dysenteria_ was published at {781} Wittenberg in 1626. Sennert gave the deathblow to tenesmus as a distinct disease, or as even a pathognomonic sign of dysentery, showing that it is often present in purely local troubles, ulcers, fissures, hemorrhoids, etc., or is due to disease of other organs--stone in the bladder, tumors in the womb, etc. He recognized sporadic and epidemic attacks of the disease, and described under the terms fiens and facta forms which coarsely correspond to the catarrhal and diphtheritic varieties of modern pathologists. Improper food, unripe fruits, at least, cannot be the cause of dysentery, because, he shrewdly observes, the epidemic of 1624 began in May, before the fruits were ripe, and ceased in autumn, when they were ripe and in daily use. Moreover, sucklings at the breast suffered with the disease. Nor could moisture alone account for the disease, as this epidemic occurred after an unusually hot and dry spring and early summer. Some other cause must be invoked, and this other cause is perhaps the occult influence of the constellations and planets--an explanation which he afterward admits to be only an asylum of ignorance. In the treatment of the disease the indication should be to heal the abraded or ulcerated intestine; but since this cannot be done unless the cause is first removed, "the abrading, eroding humor should be evacuated and absterged, at the same time its acrimony mitigated and corrected; then the flux should be checked by astringents, and the pain, if vehement, lenified and removed." Purgatives should be repeated until all vicious humors are discharged.

Sydenham colored his descriptions of the epidemic which he witnessed in London in 1669-72 with the artistic touches of the master's hand. "The disease sets in," he says, "with chills and shivers. After these come the heat of the fever, then gripings of the belly, and lastly stools. Occasionally there is no fever; in which case the gripes lead the way, and the purging follows soon after. Great torment of the belly and sinking of the intestines whenever motions are passed are constant; and these motions are frequent as well as distressing, the bowels coming down as they take place. They are always more slimy than stercoraceous, feces being rarely present, and when present causing but little pain. With these slimy motions appear streaks of blood, though not always. Sometimes, indeed, there is no passage of any blood whatever from first to last. Notwithstanding, provided that the motions be frequent, slimy, and attended with griping, the disease is a true bloody flux or dysentery." The efficacy of opium in its treatment causes him to break out in praises of the great God who has vouchsafed us a remedy of so much power. But Sydenham was too good a practitioner not to know that all treatment must be prefaced with laxatives. For "after I had diligently and maturely weighed in my mind," he says, "the various symptoms which occur during this disease, I discovered that it was a fever--a fever, indeed, of a kind of its own--turned inwardly upon the bowels. By means of this fever the hot and acrid humors contained in the mass of the blood, and irritating it accordingly, are deposited in the aforesaid parts through the meseraic arteries." The indications then were plain--viz. "after revulsion by venesection to draw off the acrid humors by purging." It was the frequent and successful practice of Sydenham also to drench the patient with liquids, per os et per rectum--a mode of treatment which both he and the learned Butler, who accompanied the {782} English ambassador to Morocco, where dysentery was always epidemic, hit upon, "neither of us borrowing our practice of the other." Butler declared that the method of deluging the dysentery by liquids was the best. But many attacks are cured almost on the expectant plan alone. This was the case with the excellent and learned Daniel Coxe, Doctor of Physic, in whom "the gripes and bloody motions ceased after the fourth clyster. He was kept to his bed, limited to milk diet; and this was all that was necessary in order to restore him to perfect health."

Zimmermann (1767) did not believe that improper food could be a cause of dysentery, as in the epidemic of 1765 fresh grapes were plentifully supplied to patients and proved an excellent remedy. He also noticed the muscular pains (rheumatism) which had been mentioned by Sydenham before him, and the paralyses first noticed by Fabricius in 1720, as occurring in the course of, or as sequelæ to, the disease. It was only contagious, he thought, in bad cases, when the stools have a cadaveric odor. But his main and most useful contributions were in the field of therapy. He discarded venesection entirely, was among the first to recognize the value of ipecacuanha, and objected strenuously to opium until the cause of the evil was expelled. Hence he was vehemently opposed to all astringents, to the use of which he ascribes the rheumatisms and dropsies which sometimes occur. Wines and spices were likewise put under ban; whey he permitted, but not milk, and water freely, but always warm. Barley-water and cream of tartar were sufficient food and medicine for ordinary cases, while camphor and cinchona best sustain the strength in bad cases.

Pringle (1772) observed the frequent occurrence of dysentery coincidently with malarial fever, and was a firm believer in the contagion of the disease. He claimed that the foul straw upon which the soldiers slept became infectious, but maintained that the chief source of infection were the privies "after they had received the dysenteric excrements of those who first sicken." It is spread in tents and in hospitals, and may be carried by bedding and clothing, as in the plague, small-pox, and measles. Neither food nor drink propagates the disease, he thinks, for, so far as the fruits are concerned, he too had seen it prevail before the fruits were ripe. The first cause of the disease is "a stoppage of the pores, checking the perspiration and turning inward of the humors upon the bowels." Antimony was his specific in its treatment. He was also fond of Dover's powder in its relief, and preferred fomentations to opium, which "only palliates and augments the cause." The best drink for patients with dysentery was lime-water (one-third) and milk.

This period of time is made memorable in the history of dysentery, as of nearly all internal diseases, by the contributions from direct observation upon the dead body by the father of pathological anatomy, John Baptist Morgagni (1779). From the days of Hippocrates down, the seat of the disease had been, as has been shown, pretty accurately determined, and the same acumen which enabled the clinicians to localize the affection had inspired them, as we have seen, to define and describe its nature. But any descriptions from actual post-mortem examinations were not put upon record until the beginning of the sixteenth century, when were published the posthumous contributions of Benivieni (1506-07). In his description of the lesions of the disease he says that "the viscera displayed {783} internal erosion from which sanies was continually discharged." Nearly three centuries elapsed before Morgagni made his anatomical studies--an interval of time void of any contributions from pathological anatomy; and so little attention was paid to this branch of medical science that the descriptions of Morgagni and of his more immediate successors failed to excite any general interest or make any permanent impression. Morgagni himself, while he fully recognized their significance, did not consider the ulcerations of dysentery as absolutely essential to the disease, as many cases, even fatal ones, did not exhibit them at all. They were not liable to be mistaken for the lesions of typhoid fever, the ulceration of Peyer's glands, because, though they may, they only rarely, coexist in the same subject. As to the membranous fragments sometimes evacuated with the discharges of dysentery, Morgagni showed that they are occasionally true fragments or shreds of the intestinal coats, as has been maintained by the older writers, Tulpius and Laucisius, but are far more frequently nothing else than inspissated mucus--conceptions which subsequent studies with the microscope have fully confirmed.

In view of the general disregard of direct observations, it is therefore not surprising to learn that the nature of the intestinal lesions gradually fell into oblivion or at least became underrated in its import. But it is a matter of surprise that Stoll (1780) was able to declare as the result of autopsies made by himself that, although the colon is thickened and inflamed, ulcerations in dysenteries are very rare. This distinguished author did not at all believe in the contagion of the disease, as he had never seen it attack physicians or nurses. It developed, he thought with the older writers, as the result of exposure to cold during a perspiration. He emphatically insisted upon the frequency of rheumatism as complicating the disease, and describes in proof a number of cases of painful swollen joints during and subsequent to the attack. It was his especial merit to have succeeded in dispensing with the acrid bile as a cause of the disease, maintaining that hepatic derangements were only accidental complications, and thus disposed, but only for a time, of bilious dysentery in so far as it was supposed to depend upon defective or abnormal action of the liver.

But Annesley (1828) soon reinstated the liver in the pathology of dysentery, with the exhibition of colored plates displaying abscess of the liver in connection with the disease, as well as illustrating the displacements and constrictions of the colon which sometimes occur in its course.

The fourth decade of our century now brought in the anatomical contributions of Cruveilhier and Rokitansky, to be followed later by those of Virchow, upon which the modern morbid anatomy of the disease is based; while the labors of the Indian physicians and of Copeland, Parkes, and Vaidy put us in possession of the facts pertaining to its general pathology. Fayrer has quite recently published the results of his vast experience with dysentery in India, an important contribution to the practical study of the disease, and Hirsch has treated exhaustively of its medical geography. But the merit of publication of the most complete chapter or work upon dysentery that has ever been written anywhere belongs to, and is the especial pride of, our own country. It constitutes the bulk of the second volume of the _Medical and Surgical History of the War of the Rebellion_. It is a veritable encyclopædia of knowledge, not {784} only upon the subject of which it treats, but upon all subjects immediately or even remotely collateral to it, and is a lasting monument to the labor and the learning of its author, Joseph J. Woodward, Surgeon of the United States Army.

GENERAL REMARKS.--Dysentery may be a primary or a secondary disease. As a primary disease it occurs in sporadic, endemic (often closely, sometimes curiously, circumscribed), or epidemic form, and is either acute or chronic, according to the nature of its symptoms and lesions. The ancient types of sthenic and asthenic or adynamic, typhoid, bilious, and malarial dysenteries belong rather to history than to modern medicine. The classification of cases in general use at present--viz. the catarrhal and croupous or diphtheritic forms--has reference rather exclusively to the nature of the lesion, and is hence extremely defective. Nor are the divisions (as in cholera) into sporadic and epidemic forms much more satisfactory, in that they indicate simply the range or extent of the disease, and by no means define a separate array of symptoms or lesions; precisely the same symptoms or lesions being encountered in individual cases of either form. None of these divisions clearly indicate differences in etiology, upon which factor alone can any acceptable division of cases be based. Perhaps less objection may be urged against the assumption of catarrhal and specific forms, including under the provisional term catarrhal all the cases which cannot as yet be accounted for by the action of a special or specific cause.

It will become apparent in the study of the etiology of dysentery that while any of the factors invoked may suffice to produce the catarrhal (sporadic) form, none will explain the specific (epidemic) form of the disease; both forms may be alike in their lesion and signs, but they differ widely in their cause. In other words, dysentery is only a clinical, and is in no way an etiological, expression of a disease. In this respect dysentery finds its analogue in a much grosser lesion of the bowels--namely, occlusion, acute or chronic, which, while it presents pretty much the same train of symptoms, may depend upon a great variety of causes, as impaction, strangulation, intussusception, etc. While any of the causes cited may be sufficient to excite the catarrhal form of the disease, the same causes may stand to the specific form only in the relation of predisposing agents. Or, as Maclean has better put it, "It appears that many of the so-called causes of dysentery must be regarded more as acute agents of propagation than of causation."

As a secondary disease dysentery occurs in the course of, or as a sequel to (not infrequently as the terminal affection of), pyæmia and septicæmia (puerperal fever), typhus and typhoid fevers, pneumonia, Bright's disease, variola, scarlatina, abscess of the liver (though the order of sequence is here oftener reversed), scorbutus, marasmus from any cause, tuberculosis, and cancer. It must not be forgotten, however, of these latter affections that each produces its own lesions in the large intestine, which are not to be confounded with those of genuine dysentery.

The view that dysentery shows a periodicity of recurrence at certain distinct intervals or cycles--three, five, or ten years--is entirely without foundation in fact; but there is strong ground for believing that the disease is gradually abating both in frequency and virulence with improvements in sanitation and hygiene. Thus, Heberden shows that the {785} number of deaths set down in the seventeenth century under the titles of bloody flux and gripings of the guts was never less than 1000 annually, and in some years exceeded 4000, whereas during the last century the number gradually dwindled down to 20 (Watson)--a number which is certainly a misprint for 200; and Aitken states that as a cause of death it has been decreasing since 1852. Geissler also remarks[1] that the variation in epidemics is nowhere so well illustrated as in the case of dysentery. A noticeable reduction in the number of cases in England began about 1850, and has continued almost without interruption to the present time, so that now (1880) six to eight times less cases occur than in the forties. The same diminution has been noticed in Bavaria and Sweden. In Sweden the cases treated by physicians in 1857 numbered no less than 37,000, with over 10,000 deaths; whereas now the number is reduced to 400-500 a year, and the mortality has experienced a corresponding reduction from 20-30 to 6-8 per cent.

[Footnote 1: _Periodische Schwanderungen der wichtigsten Krankheiten_.]

At the same time, it is known of dysentery that it sometimes shows an almost freakish recurrence after long intervals of time, appearing in a place for many decades free from the disease, to establish itself there for years as a regular endemic malady, not to disappear again for a long series of years; in which respect, Hirsch remarks, it much resembles malaria.

Allusion has been already made to the occasional curious circumscription of the disease in definite localities. In fact, dysentery, even when late to assume the proportions of a widespread epidemic, begins, as a rule, and is confined for a time, in individual enclosed regions--prisons, barracks, hospitals, etc.; and in the process of dissemination it is rather characteristic of the disease to leap over or to spare intervening territory and appear in new foci at some distance from its original seat. A direct irradiation or linear transmission of the disease is the exception, and not the rule. The significance of this fact will become evident in the study of the etiology of the disease.

Dysentery is pre-eminently a disease of army life, its victims among soldiers numbering more than all other diseases together. Sir James MacGrigor, Medical Superintendent of the British army, called it the scourge of armies and the most fatal of all their diseases. Aitken says that "it has followed the tracks of all the great armies which have traversed Europe during the continental wars of the past two hundred years." It decimated the French, Prussian, and Austrian armies in 1792. In Cape Colony in 1804 every fourth man among the soldiers was attacked with the disease, and of those attacked every fifth man died. In Napoleon's campaign in Egypt dysentery numbered one-half more victims than the plague; Kinglake says that 5000 men died of dysentery alone in the war of the Crimea; and in our own country during our Civil War from 1861-65 chronic camp dysentery was the cause of more than one-fourth of all the diseases reported, the mortality being at the rate of 12.36 per 1000.

Woodward relates that the dysenteries, acute and chronic, with diarrhoeas, made their appearance in the new regiments at the beginning of the war, and, though mild at first, quickly assumed a formidable character. "Soon no army could move without leaving behind it a host of the victims. They crowded the ambulance-trains, the railroad-cars, the {786} steamboats. In the general hospitals they were often more numerous than the sick from all other diseases, and rivalled the wounded in multitude. They abounded in the convalescent camps, and formed a large proportion of those discharged for disability." Most of the prisoners died of this disease, and great numbers succumbed to it on retirement to their homes after the cessation of the war. It is the story of many a campaign, Eichhorst says, that dysentery kills more men than the enemy's guns.

The fact that it sometimes shows itself in periodic form or with periodic exacerbation, that it is sometimes successfully treated with quinia, and that, as has been noticed from the days of Hippocrates down, it prevails in greatest intensity in malarial regions, has given rise to the view that dysentery is a malarial disease. This view, which was strongly advocated by many of the older writers, Senac, Fournier, Annesley, met with renewed support at the hands of many of the surgeons in our Civil War. But wider observation has shown the fallacy of such a view; for not only may the diseases prevail entirely independently of each other in malarial regions, but there are regions where one does and the other does not exist. Thus Huebner quotes from Rollo concerning St. Lucie (West Indies), a town situated on a mountain in the midst of a swampy country in which both dysentery and malaria abound, while the town itself is almost free from dysentery; and Dutrolan cites Réunion as a place where marsh fevers do not occur, while dysentery is very common. Bérenger-Féraud[2] scouts the idea of any such connection. "Let us mention only St. Pierre de la Martinique," he says, "where there is not a piece of marsh as big as a hand, but where dysentery has made great ravage more than once. We might cite also Mauritius, Gibraltar, Malta, New Caledonia--places exempt, or almost exempt, from malaria, but often visited by dysentery."

[Footnote 2: _Traité théorique et clinique de la Dysenterie, etc._, Paris, 1883.]

The view that dysentery is a form of typhus or typhoid fever (Eisenmann) or scurvy needs no refutation in the light of existing knowledge regarding the pathogenesis and pathology of these affections. These diseases may often complicate, but can never cause, dysentery.

Dysentery is a disease which spares no age, sex, or social condition, the seeming greater suffering of the poorer classes being due to the filth, food, darkness, dampness--in short, to the bad sanitation--of poverty.

Though the disease is often confined exclusively to soldiers in the midst of a civil population, examples are not wanting of an exclusive selection of civilians or of an indiscriminate attack in every direction. Lastly, dysentery is a disease which may recur repeatedly in the same individual, one attack rather predisposing to than preventing another.

ETIOLOGY.--Dysentery is an omnipresent disease. "Wherever man is," Ayres observed of it nearly a quarter of a century ago, "there will some of its forms appear." But the character of the form, and more especially the extent and severity of the disease, vary in extreme degree with the conditions surrounding the abode of man. No one of these conditions affects the disease so markedly as the climate. It is the testimony of Hirsch, based upon the study of seven hundred epidemics of the disease, that no other disease is so dependent upon the influence of the climate. The home of dysentery is the tropical zone. It prevails in greatest frequency {787} and virulence in the tropics, and in those regions of the tropics where the characteristics of this zone are more pronounced, diminishes in intensity in the temperate regions, and occurs only in sporadic form farther north. At 40° latitude the line may be pretty sharply drawn; beyond it dysentery as an epidemic is almost unknown.[3]

[Footnote 3: Shakespeare (_Troilus and Cressida_) cites "griping of the guts" among the "rotten diseases of the south."]

India has been from time immemorial the hotbed of this disease. Henderson says it is perhaps more fatal to natives than all other diseases put together, and Hutchinson, Hunter, and Tytler observe that it causes three-fourths of the deaths among the natives of Hindostan. In Egypt the disease is indigenous, and is, according to Frank, post pestem maxime timendus. Greisinger reports that one-half of all the autopsies made by him in Egypt showed dysentery as a primary or secondary affection. It is epidemic here at all times, Roser says, and all fatal cases of acute or chronic disease finally perish with it.

Similar testimony might be adduced from a large part of Africa, much of Asia, the Indian Archipelago, and the West Indies. It rages "murderously" in Peru, causing a mortality in some epidemics of 60 to 80 per cent., and occurs in this country not only in the valleys, but in cities and provinces at the lofty elevation of 8000 to 13,000 feet.

Heat, moisture, vegetable decomposition, and sudden atmospheric change are the distinguishing characteristics of southern climes, and the study of the etiology of a disease incident or indigenous to these conditions calls for an investigation of these various factors.

It is well established of dysentery that it occurs for the most part in the hottest season of the year. Of 546 epidemics tabulated by Hirsch, 404 prevailed in summer and fall, 113 in fall and winter, 16 in spring and summer, and only 13 in winter. Fourteen-fifteenths of the whole number of epidemics occurred in the months of June to September. And it is corroborative of these conclusions that of 1500 deaths from dysentery in the cities of Boston, New York, Philadelphia, and Baltimore from 1816 to 1827, 1100 occurred in the months of July, August, and September. In fact, the Census Reports (1860-70) of our country show the maximum mortality in August and September, and the minimum in January and February.

The prevalence of unusual heat may also call out an epidemic in places where the disease usually shows itself only in endemic or sporadic form. Thus, the severe epidemic of 1540 in England was preceded by a heat so intense as to dry up the wells and small streams, in consequence of which many cattle died of thirst; and the epidemics of 1583 in Germany, of 1758 in France, and of 1847 in our own country, were characterized in the same way. Interesting in this connection is the statement of Frick concerning the epidemic in Baltimore in 1849, who found the cases to increase and decrease almost in proportion to the elevation and depression of temperature. The epidemic of Weimar in 1868, where 12,000 people fell ill with the disease, illustrated the rule when it ceased suddenly on the approach of cool weather at the end of August.

But that heat alone is not sufficient to account for the genesis of the disease is apparent from the occasional occurrence of it in the tropics in the colder seasons of the year; in the colder climates, Russia, Sweden, {788} and Canada; and in temperate regions during exceptionally cool seasons, as in Plymouth in 1769, London in 1808, Massachusetts in 1817. Moreover, the temperate zone is often characterized by seasons of unusual heat, during the prevalence of which dysentery may be almost unknown. Thus, during the summer of 1881, in Cincinnati, the thermometer scarcely fell below 95° F. for weeks at a time, and was often nearly 100° during the entire night, but the records at the Health Office show that while cases of heatstroke were alarmingly frequent, dysentery was unusually rare during the entire season.

That moisture cannot act more, at most, than as an occasional predisposing cause of dysentery is sufficiently clear from the statement of Hirsch, that of 119 epidemics, 62 commenced or were preceded by wet and 57 by dry weather. In truth, dryness long continued and excessive heat have already been invoked as remote causes of the disease. But moisture, as contributing to, or being a necessary element of, vegetable decomposition, the third characteristic of tropical regions, is entitled to further consideration. Annesley observed that among troops stationed in the vicinity of rivers, canals, and places abounding with emanations from the decay of animal and vegetable matters dysentery became extremely prevalent and assumed a more or less malignant nature; and Baly, who studied the disease in its famous outbreak in the Milbank Penitentiary, remarks that "it is greatest at those seasons and in those states of the atmosphere which most favor decomposition of organic matter in the soil."

In Africa it has been noticed that dysentery appears with the rainy season, to disappear only at its close; and the same observation has been made of Bengal, while in Lower Egypt the disease follows the inundations of the Nile. Burkhardt says of 10,000 cases that one-half occur in wet hot seasons, two-fifths in dry hot seasons, and but one-tenth in cold seasons. Moreover, the removal of camping-grounds to dry localities has often arrested the disease or checked its further dissemination. Thus, Mursinna states that the removal of the army of Prince Henry of Hesse from Nîmes, where the disease raged fearfully, to Leitmeritz was attended by its immediate cessation, notwithstanding the fact that the soldiers ate large quantities of fruit. A statement of Dillenius, quoted by Heubner, is in this connection exceedingly instructive: "Dillenius had to march with a dysentery hospital of more than 500 patients from July 26 to August 3, 1812, and it required four whole days to accomplish an ordinary nine or ten hours' march. The patients, extremely exhausted, were finally put into a sheep-shed. Here, in the fresh air and lying on hay, they all improved very quickly. By advice of the physician they ate for medicine the fresh whortleberries which they themselves had picked." Werneck attributes the exemption of the city of Halle since the end of the last century to the draining and drying of the neighboring marshes.

On the other hand, numerous observations go to prove that dysentery is likewise prevalent in dry sandy soils where the factors so necessary to the production of malaria are entirely unknown. Thus, Hirsch quotes from Harthill to the effect that dysentery never occurred among the English troops in Afghanistan until they entered upon its thoroughly dry and sandy plains; and from Lidell, who declared that the disease prevailed most in Panama in March, the dry season at this place. Again, a striking confirmation of exemption from dysentery in a marshy region {789} is offered in the Antilles at Grande-Terre, "a wet, marshy plain severely visited by malaria, but used by patients attacked with chronic dysentery at Basse-Terre as the safest place of refuge and recovery."

The rôle of moisture and vegetable decomposition may be, then, summed up in the words of Annesley, that "all situations which furnish exhalations from the decay of animal or vegetable productions under the operation of a moist and hot state of the atmosphere will always occasion dysentery in the predisposed subject--_circumstances which, with other causes_ [italics ours], combine to generate the disease."

Atmospheric vicissitudes, checking of perspiration, catching cold, are synonyms in the present popular as in the ancient professional conception of the genesis of dysentery. "Of the remote causes of dysentery," Johnson says, "I need say little; they are the same in all parts of the world--atmospheric vicissitudes." And in making this statement the author expresses the almost universal testimony of the Indian physicians. "Sudden change of temperature," observes Kaputschinsky of the Trans-Caucasus, where dysentery is rife, "is in this region no rarity. The sultry heat of noon often alternates with a cutting cold wind, and vice versâ. In the same place is now a warm, now a cold, now a glowing hot breeze, and such changes most predispose to dysentery." And McMullin says of the Barbadoes that "it is a curious fact that this disease is most prevalent where from the immediate contiguity of mountains sudden vicissitudes of temperature are experienced." Didelot says also of South France, "It is not the fruits, as people still believe to-day, which act as causes of dysentery, but the sudden variations of the air." Ruthay remarks of the dysentery of China that the most common cause is a chill caught by sleeping in a draught uncovered or in the open air. Metzler attributes the exemption of Stuttgart (since 1811) from any great epidemic to the fact that the city lies in a valley open only to the east, which permits no contrast of hot days and cold nights; and Seeger, in speaking of the epidemic which occurred in Ludwigsberg in 1872 (a city of twelve thousand population, where no epidemic of any kind had appeared since 1834, and where 870 were suddenly attacked with dysentery) that it first broke out in Kaffeeburg in two streets exposed to the wind, and thence spread to different parts of the city. Exposure of the body, especially the abdomen, during sleep or when perspiring, the sudden laying aside of flannel body-clothes, are proceedings, Fayrer says, pregnant with danger in dysenteric regions. A lamentable dysentery appeared, according to Trotter, on board H.M.S. Berwick Oct., 1780, "in consequence of the hurricane on the fifth of the month, by which the clothes and bedding of the seamen, and indeed all parts of the ship, were soaked in water, and many of the men slept for nights together on the wet decks overcome with fatigue and debilitated from want of food." Fayrer also quotes from Moseley the observation that "it often happens that hundreds of men in a camp have been seized with the dysentery almost at the same time after one shower of rain or from lying one night in the wet and cold."

As illustrating the conjoined operation of all these various causes, together with filth and foul effluvia, more especially exposure to cold, the story of dysentery was never better told than by Sir James MacGrigor, who, in speaking of the Peninsular campaign, remarks that "the army during June as well as July was traversing Castile, where it was {790} exposed to the direct influence of a burning sun darting its rays through a sky without a single cloud, the troops marching and fighting during the day, and bivouacking during the night on arid, unsheltered plains. They felt at times every vicissitude of heat and cold. In the rapid advance they could not be regularly supplied with food or had not time to cook it, and not unfrequently indulged in bad wine and unripe fruit." ... The thousands of sick (chiefly from diarrhoea, dysentery, and remittent fever) were hurried off to Ciudad Rodrigo, the nearest hospital-station to the frontier of Portugal, a town "composed chiefly of ruins with very narrow streets," ... and from having been "so much the object of contest, and alternately the site of the hospitals of all the contending armies, nearly twenty thousand bodies were calculated to have been put into the earth either in the town or under its walls in the course of a few months." ... "It may easily be conceived," the author adds, "in what state cases of dysentery must have arrived after having sustained a journey in extent from four to twenty days, conveyed chiefly in bullock-carts or on the backs of mules, sometimes under incessant rain for several days together."

It is really quite superfluous to cite further opinions or examples in illustration of a fact which is so universally conceded as to be exaggerated in its general significance. Taking cold is the common idea of the cause of dysentery, and is always a satisfactory explanation in a case of obscure origin in this or any disease, even though the patient may be able to recall no possible exposure. The physician himself contents himself only too easily with resort to this refuge, and with further appeal to the locus minoris resistentiæ, as the explanation of the seat of the disease, which he hopes to cure with the aid of the vis medicatrix naturæ. But taking cold is only a popular paraphrase for contracting a disease, and will bear no scientific analysis of its meaning. Mere reduction of temperature will certainly not produce a disease whose habitat is the hottest zone, nor will a sudden chill of the surface be accepted as a sufficient cause so long as men daily remain exempt after a sudden plunge into cold water. Some other factor must be invoked to account for the outbreak of specific (epidemic) dysentery.

The influence of the nervous system, the mechanical and chemical or specific action of the ingesta and dejecta, remain to be especially considered in the etiology of the disease.

The influence of the nervous system is more directly seen in the production of diarrhoeas than dysenteries, but that sustained disturbances of the emotions play an important part in the production of dysentery is shown by the greater frequency of the disease among prisoners of war. In the Franco-Prussian war the French prisoners suffered more than the Germans, and the records of prison-life in our own war, at Andersonville, Libby, and Salisbury, furnish ghastly chapters in the history of this disease. Many other factors contribute to the development of the disease under such circumstances--in fact, all the cruelties of man's inhumanity to man--but the influence of the nervous system is too plain to be mistaken. The communication between the cervical ganglia and the sympathetic nerve-fibres which preside over the cerebral circulation and regulate intestinal peristalsis has been invoked (Glax) in explanation of the direct action of the brain upon the intestinal canal. Curious in this {791} connection is the claim of Savignac, who considered dysentery a disease of the nervous system because in two cases he found spots of softening in the spinal cord.

The noxious action of irritating articles of diet has been recognized in the production of dysentery from the earliest times. Aretæus mentions acrid foods, and Aëtius crudities, as directly causing the disease; and unripe fruits have been especially stigmatized from the days of Galen down. Decomposing, fermenting food and drink cause diarrhoea much more frequently than dysentery, but if the irritation be severe or prolonged, or be superimposed upon a catarrhal state, a diarrhoea, it is claimed, may pass over into dysentery. Impurities in drinking-water were charged with causing dysentery by Hippocrates himself, with whom Avicenna fully coincided; and the view that epidemics of the disease are caused in this way has been abundantly advocated ever since. So far as running water is concerned, the researches of Pettenkofer have shown that all impurities are speedily destroyed, for even at the distance of a few rods from the reception of sewage the water is perfectly safe. Nor does standing water lack the means of purification, provided it be sufficiently exposed to the air. The observations of Roth and Lex have shown that the water of the wells of fifteen churchyards in Berlin contained nitrates in less quantity than the average wells in the city; and Fleck made a similar statement with regard to the wells of Dresden. But no one in our day would rely upon a mere chemical analysis in the detection of the organic poisons or particles of disease. It is the physiological test which remains the most conclusive, and the evidence in favor of the production of dysentery by the ingestion of drinking-water poisoned by the reception of excrementitious matter, especially the dejecta of disease, is as positive as in the case of typhoid fever. Thus, De Renzy found that the number of cases of dysentery "immediately decreased at Sibsagor (India) so soon as better drinking-water was obtained from wells deeply sunk and lined with earthenware glazed pipes;" and Payne found that the cases of dysentery (as well as diarrhoea and lumbrici) almost disappeared from the asylum at Calcutta as soon as the habit of drinking water from the latrines was stopped. In face of such facts, which might be infinitely multiplied, one would hesitate to subscribe to the statement of Fergusson that "true dysentery is the offspring of heat and moisture, of moist cold in any shape after excessive heat; but nothing that a man could put into him would ever give him a true dysentery."

The relation of the action of the dejecta must be studied from the double standpoint of the development and the dissemination of the disease, as originating the catarrhal form by mechanical or chemical irritation of the intestinal mucosa, and as spreading the specific form by direct or indirect infection.

By the time the contents of the alimentary canal have reached the colon they have become, through absorption of their fluids, more or less inspissated, and hence as hard, globular masses fill the sacculi of the large intestine. Mechanical irritations by crude, indigestible residue of any kind of food, more especially of vegetable food, or chemical irritations, as by fermenting food, accumulate in this region, fret the mucous membrane into a state of inflammation, even ulceration, and produce the anatomical picture and the clinical signs of dysentery. If there be a superadded or {792} pre-existent catarrhal condition of the mucosa or a defective peristalsis of the muscular coat, which is sluggish enough at best, the development of a pathological state is much facilitated. And there is no doubt that the dysentery of the tropics is increased by the bulky, indigestible, feces-producing character of the food.

The anatomical construction of the colon may also favor these processes by its mere abnormal length or size or by duplicatures in its course. The protracted constipation of the insane, in whom the transverse colon is often found elongated or displaced--to assume the well-known M-form, for instance--may partially account for the frequency of dysentery in these cases (Virchow), though the neglect which comes of preoccupation of the mind, with the general inhibition of peristalsis, is a more frequent cause of the constipation.

Wernich (1879) sums up the action of the feces, independently of a specific cause, in attributing the dysentery of the tropics, aside from the great changes of temperature, to (1) bad aborts, the dejecta being deposited in all parts of the towns or into an opening made in the floor of the hut, with which is associated total lack of personal cleanliness; (2) to the diet, which causes a large amount of feces; and (3) to the relaxation of the intestine in general, permitting accumulations of infecting matter.

Upon the question of the propagation of the disease by the dejecta rest in great measure the all-important problems of a specific virus and of the contagiousness of the disease.

It is the almost universal opinion of those who have had the opportunity of widest observation that epidemic dysentery arises from, or is due to, a specific cause, a miasm, a malaria (in its wide etymologic sense, bad air), which emanates from the soil. The simultaneous sudden attack of great numbers under the most diverse surroundings admits of explanation in no other way. But the precise nature of the morbific agent is still unknown. The similarity of epidemic dysentery to malaria would indicate the existence of a low form of vegetable life, a schizomycete, as the direct cause of the disease. But the proof of the presence of a specific parasite or germ is still lacking, and though its speedy disclosure by means of the solid-culture soils may be confidently predicted, it cannot, in the light of existing knowledge, be declared as yet.

Especial difficulty is encountered in the study of micro-organisms in diseases of the alimentary canal because of the myriad variety in enormous numbers found in healthy stools. Decomposition and fermentation both begin in the large intestine, so that the feces swarm with the bacteria and torulæ productive of these processes. Woodward declares that his own observations have satisfied him that "a large part of the substance of the normal human feces is made up of these low forms in numbers which must be estimated by hundreds of millions in the feces of each day," bacteria, micrococci, and torulæ being found "floating in countless multitudes along with fragments of partly-digested muscular fibres and other débris from the food;" but while the torulæ are increased, the other micro-organisms, bacteria, etc., do not appear to be more numerous in the stools of dysentery than in healthy feces.

The doctrine that dysentery depends upon parasites is very old in medicine, and included animal as well as vegetable growths. Langius (1659) declared that swarms of worms could be found in dysenteric stools, and {793} Nyander (1760) went so far as to call dysentery a scabies intestinorum interna; which extravagant conception would have speedily met with merited oblivion had not his preceptor, the great Linnæus, incorporated the Acarus dysenteriæ into his _Systema Naturæ_. Sydenham about this time (1670) expressed a much clearer conviction of the cause of the disease when he spoke of "particles mixed with the atmosphere which war against health and which determine epidemic constitutions."

Baly (1849) first proclaimed the idea of a vegetable fungus, similar to that described by Brittan and Swayne in cholera, as the parasite of the disease; and Salisbury (1865) described algoid cells and species of confervæ as occurring abundantly in all well-marked cases. Klebs (1867) found spore-heaps and rod-like bacteria in the stools of dysentery as in cholera, but maintained that those of dysentery were larger and thinner than those of cholera. Hallier (1869) maintained that although there was no morphological difference in the micro-organisms of the stools of dysentery, typhoid fever, and cholera, he was able by culture-experiments to develop the micrococcus of dysentery into a special fungus, which he called Leïosporium dysentericum. Busch (1868) demonstrated nests and colonies of micrococci, as well as mycelium, in the villi and among the glands of the mucous and submucous tissues in the cases of dysentery from Mexico which he examined, but Heubner (1870) was able to disclose them in equal numbers in preserved preparations or fresh contents of healthy intestines. Dyer[4] (1870) believes that the parasites constituting the mildew or sweat which forms a viscous pellicle upon fruit is the agent which directly produces and propagates the disease. Mere immaturity of fruit gives rise only to diarrhoea. This parasite occurs in some years more than others, which accounts for the irregularity of occurrence of the disease. He avers that it is only necessary to clean fruit, more especially plums, to prevent the disease. This suggestion merits place only as a curiosity in the history of the mycology of dysentery.

[Footnote 4: _Journal f. Kinderkrankheiten_, No. 317.]

More important are the results of the experiments of Rajewski (1875), who found the lymph-spaces filled with bacteria, and who was able to produce a diphtheritic exudation upon the surface and in the substance of the mucous membrane of the colon by the injection of fluids impregnated with bacteria into the bowels or blood of rabbits; but this result was only obtained when the mucous membrane had been previously irritated or brought into a catarrhal state by the introduction of dilute solutions of ammonia. It remains for subsequent investigation to confirm these highly significant conclusions, which, when properly interpreted, may explain the action of the predisposing and exciting causes of the disease. Rajewski's bacteria, it is needless to state, were simply the bacteria of common putrefaction. Lastly, Prior (1883) describes a micrococcus as the special micro-organism of dysentery, and Koch (1883), in prosecuting his studies of cholera in Egypt, remarks incidentally upon a special bacillus which he encountered in the intestinal canal in dysentery, though he is as yet by no means prepared to ascribe to it pathogenetic properties.