Tropical Diseases/Chapter 25
Section II.—GENERAL DISEASES OF UNDETERMINED NATURE
CHAPTER XXV
BERIBERI (KAKKE, BARBIERS)
Definition.— Beriberi is a form of multiple peripheral neuritis occurring endemically, or as an epidemic, in most tropical and sub-tropical climates, and also, under certain conditions, in more temperate latitudes. The mortality is considerable, death usually depending on heart paresis.
Historical.— The special nature of beriberi was recognized by the Dutch in the early years of their intercourse with the East. Later, it was studied by British physicians in India, particularly by Malcom sen, Carter, Waring, and Morehead. It was not until a more recent epidemic in Brazil that beriberi began to receive attention from the present generation of medical men ; and only when Anderson, Simmons, Scheube, and Baelz took up the subject in Japan was it studied by modern methods, accurately defined, and its true pathology apprehended. Scheube and Baelz were the first to show distinctly that beriberi is of the nature of a peripheral neuritis similar to that of diphtheria and alcohol a view which was subsequently confirmed and adopted by Pekelharing and Winkler, and by most subsequent observers. More recently, and mainly owing to the investigations of Eijkman, Braddon, Fraser, and Stanton, its principal it may not be the only etiological factor has been shown to be a dietary of which the staple ingredient is over-milled rice.
Geographical distribution.— The area of the endemic distribution of beriberi is coextensive, probably, with the tropical and sub-tropical belts; doubtless it exists in many places where its presence is not generally suspected. It is the scourge of many of the mines and plantations of the Malay and Eastern Archipelago. It is apt to break out among the coolie gangs engaged on extensive engineering works in the tropics, such as the Panama Canal or the Congo Railway. It haunts the Dutch army in Sumatra, and used to be common enough in the British armies in India. It is at home in many parts of Japan, particularly in her large, low-lying, damp, overcrowded cities. It occurs in China, the Philippines, the Eastern Peninsula, India, and Africa. It is prone to break out in gaols, in schools, in ships. Some- times, as an epidemic wave, it passes over a tropical country, as was the case in the early 'sixties in Brazil, where it still lingers. Sometimes sporadic cases crop up here and there. Generally, when it appears in a community, it attacks large numbers, picking out particular houses and districts. Lately we had an account of a small epidemic among a group of Western Australian natives, and also among Chinese on the eastern seaboard of Australia, a continent where beriberi was formerly supposed not to exist. Similarly it appeared, apparently for the first time, in Japanese immigrants in Fiji. Some time ago I saw a case having the history and clinical features of beriberi from Lake Nyasa, another from the Upper Congo, another from Hayti. We hear of it also from Havana, from New Caledonia, from the Sandwich Islands, from Uganda all of them places not before known to be liable to this disease so that the area of distribution is an extensive one. Indeed, within the last few years it would seem that it includes the temperate as well as the tropical zones. Not long ago beriberi showed itself in a lunatic asylum in Ireland Richmond Asylum, Dublin; and apparently the same disease has been seen lately in lunatic asylums in the United States and in France, and also among the fishermen on the North American coast.
Symptoms.— Medical visitors to the native hospitals in many parts of the tropical world are likely to have their attention arrested by the large proportion of cases of partial paraplegia, of cases of œdema of the legs, and of cases of general dropsy. These, for the most part, are cases of beriberi.
Fig. 74.—Paraplegic beriberi. (Bentley.)
Paraplegic cases.—On examining one of the paraplegic cases referred to (Fig. 74), it will be found that, besides paraplegia of greater or lesser degree, there is a certain amount of anæsthesia or of numbness of the skin; particularly of the skin over the front of the tibiæ, the dorsa of the feet, the sides of the thighs, perhaps also of the fingertips, and of one or two areas on the arms and trunk. The visitor may be struck with the thinness of the patient's calves, the flabby state of the gastrocnemii; and by the fact that if, whilst making the examination, he should handle these and the neighbouring muscles somewhat roughly, particularly if he should squeeze them against the underlying bones, the patient will call out in pain and try to drag the limb away. The thigh muscles may be found to be similarly affected, and so may the thenar, the hypothenar, and the arm muscles; like the calf muscles, these too may be wasted and flabby. Very probably there is a loss of fat as well, the panniculus adiposus being where very meagre. If tested electrically, the muscles exhibit to perfection the reaction of degeneration. If the knee reflex be tested in the usual way, after the first week of the disease there will be no response whatever; nor can any clonus be elicited. As a rule, all the deep reflexes are lost; but the superficial reflexes, unless in extreme conditions of paresis and muscular atrophy, are usually present and more or less active. If, in severe cases, the patient is set to button his jacket or to pick up a pin, possibly he has a difficulty about it, or perhaps he cannot; he may bungle and fumble like an advanced ataxic.
There is more than ataxia, however; for the hand grasp is so enfeebled that the patient may have a difficulty in holding his rice bowl as well as in feeding himself. There is no tremor of the hands; and never or very rarely is there any paresis of the ocular muscles, or of the muscles of the face, of mastication, of the tongue, or of the pharynx. The sphincters and bladder operate satisfactorily, and the functions of the alimentary canal are carried on fairly well, although there is often some dyspeptic distension and oppression after food. On the patient being got out of bed and started to walk, if he is able to progress at all, his gait will be markedly ataxic; but he is not ataxic merely, for, just as with the hands, it will "be seen that, in addition to want of co-ordinating power, there is great muscular weakness. If he is laid on the bed and asked to raise his legs, he is perhaps hardly able to get them off the mat, to cross them, or to place them one foot on top of the other. Very probably he is the subject of marked ankle-drop, so that he drags his toes when he attempts in walking to advance the foot; he has therefore to raise the foot very high, letting it fall on the ground with a flop when he brings it down again. His ataxia and his muscular weakness, as well as the partial anæsthesia from which he suffers, force him to adopt a variety of devices to assist him in progression (Fig. 75). Manifestly these patients are suffering from some form of peripheral neuritis.
The general health is good for the most part; the tongue is clean, the bowels are fairly regular, there is no fever, and there is nothing amiss with the urine. Digestion, assimilation, and excretion go on satisfactorily.
Fig. 75.—Paraplegic beriberi. (Bently.)
The heart and circulation.—When the heart is examined, if the case be at all recent or moderately severe, attention is at once arrested. On inspection it may be remarked that the impulse is diffuse, that there is epigastric pulsation; that the carotids throb too violently; that there is that peculiar wobbling, pulsating movement in the jugulars that denotes tricuspid insufficiency. On percussion the præcordial area is frequently found to be enlarged, perhaps very greatly enlarged, especially to the right; and on auscultation loud bruits, usually systolic in rhythm, may be heard. Marked reduplication of the sounds, particularly of the second sound, is to be noted. The auscultator may be struck, in a large proportion of cases, by the peculiar spacing of the intervals between the sounds. It may be hardly possible to tell by the ear alone which is the first pause and which is the second. They seem alike in point of duration; so that the sounds of the heart are, like the beats of a well-hung pendulum clock, evenly spaced, and not, as they are in health, separated by a long and a short interval like the beats of a badly hung clock. It will also be observed that the heart is very irritable, becoming easily quickened by exertion. It will be judged, therefore, that, in addition to peripheral neuritis, there is serious disease in the circulatory system, particularly in its innervation; that there is dilatation of the right side of the heart; and that there is a state of relaxed arterial tension.
All these signs and symptoms vary in degree from time to time in the same case, and differ in degree in different cases.
Dropsical cases.— In the next bed, perhaps, to the patient whose picture I have tried to draw may be seen another man suffering from apparently quite a different affection (Fig. 76). He is propped up in bed. Instead of being thin and wasted, as the last patient, his face is puffy and heavy; his lips possibly are slightly cyanosed; and his arms, hands, trunk, legs, and feet are distended with œdema. It may be thought from the œdema that it is a case of acute nephritis; but an examination of the scanty, dark-coloured urine shows that it is of high specific gravity, and contains no albumin, or only a mere trace; so that the case cannot be one of acute Bright's disease. Careful observation will discover that the œdema is somewhat firmer than that of nephritis, and, in not a few instances, that it does not involve the scrotum. Occasionally cases are met with in which the œdema is peculiarly localized and fugitive. If attention is directed to the heart, a bruit and other evidences of dilatation of the organ and of arterial relaxation, just as in the first case, are discovered. If the lungs be examined, one may or may not discover signs of single or double hydrothorax, although, probably, not to a very great extent. The lungs themselves are healthy. On getting him out of bed it is found that the patient can hardly walk; partly from breathlessness, partly on account of mechanical interference by the dropsy with the movements of the legs, partly, perhaps, from some degree of paresis. He has ankle-drop possibly; and, if firm pressure be brought to bear on the calf muscles through the œdema, signs of hyper-æsthesia of the muscles may or may not be elicited. Knee-jerk is probably absent, and there is numbness of the shins and fingertips. The tongue is clean, the appetite fair, and there is no fever. But there may be complaint of præcordial distress and even pain, and, as this is aggravated by a full meal
Fig. 76.—Dropsical beriberi. (Bentley.)
In this patient, therefore, there are the same signs of peripheral neuritis and of dilatation of the heart as in the other case. In addition, there is a some-what firm œdema, which is not altogether cardiac, but, as its character and the circumstances in which it is found suggest, is probably connected partly with lesion of the nerves regulating urinary excretion, and partly with the play of transudation and absorption in the connective tissues.
Mixed paraplegic and dropsical cases.— In the next bed to this patient there lies, perhaps, another case which looks like a mixture of the two preceding. There is œdema generally somewhat firm— particularly of the shins and feet, about the flanks, sacral region, and, very generally, over the sternum and root of the neck. There is numbness of the shins, there is some ataxia, there is muscular weakness and hyperæsthesia— particularly of leg and thigh muscles, there is absence of knee-jerks, there is probably a cardiac bruit and reduplication of sounds, and there are signs of dilatation of the heart and relaxed arterial tension. Just as in the other cases, the general health of the patient is unaffected, the tongue is clean, the urine though scanty is otherwise normal, and there is no fever.
Great variety in degree and combination of symptoms.— All through the wards of the hospital similar cases may be encountered. Some are so trifling that they are up and moving about with more or less freedom; and others are so severely smitten that they lie like logs in their beds, unable to move a limb or perhaps even a finger. Some are atrophied to skeletons; others are swollen out with dropsy; and some show just sufficient dropsy to conceal the atrophy the muscles have undergone. Although the cranial nerves above the seventh are very rarely involved, in some it will be noticed that the laryngeal muscles are paralysed, the patient being unable to speak above a whisper or to produce an explosive cough. In one or two cases the abdominal and the perineal muscles may be so profoundly paralysed that, when cough is attempted, at most a husky expiration is produced, whilst the belly is bulged forwards and the perineum shot downwards by the sudden contraction of the muscles of expiration. In practically all cases of over a fortnight's standing the knee-jerk and tendo-Achillis reflex are absent; at the very commencement of the disease these deep reflexes are exaggerated, gradually disappearing as symptoms develop, not to reappear for months, perhaps, after the patient is well in all other respects.
Erroneous diagnoses.— The novice in tropical medicine will be greatly puzzled for a time over these cases. I have seen them called cardiac disease, locomotor ataxia, muscular rheumatism, progressive muscular atrophy, ascending spinal paralysis, and have over and over again seen them relegated to that refuge for ignorance— malaria, and called " malarial rheumatism," or " malarial paralysis, "or, more pedantically, "malarial paraplegia," or "malarial neuritis. "*[1]
If the visitor has the curiosity to examine the blood of these patients, possibly in a proportion of them he will find microfilariæ; very likely he will then think that the cases are forms of filariasis, and he may construct theories to explain how the filaria produces the symptoms. Or, if he examine the fæces, very probably in over 50 per cent, of the cases, or, in some countries, in nearly all the cases, he will find ova of ankylostomes and, probably, those of the whipworm and the roundworm also. On this evidence he may conclude that these are cases of ankylostomiasis or other form of helminthiasis. He had better, however, not commit himself to such a diagnosis until he has ascertained how it fares with the rest of the population as regards these parasites; for he will find that the filaria, the ankylostomum, the trichiuris, and the ascaris are quite as prevalent outside as inside the hospital, and in the healthy as in the sick.
Past history of patients.— On inquiry he will learn that most of the cases come from two or three centres where similar disease is endemic from some particular institution, plantation, mine, or village. He will also remark that the same places supply both atrophic-paraly tic cases and dropsical-paralytic cases; and he will learn that many of the atrophic cases commenced with dropsical symptoms. From this he will make the important deduction that he is dealing, not with two diseases, but with two phases or clinical forms of the same disease; a disease which sometimes assumes atrophic features, sometimes dropsical features, and sometimes is of a mixed character. Some of the patients will give a history of fever at the outset of their troubles; in some there is a history of indigestion or diarrhœa; in some the paralytic or dropsical symptoms developed very slowly; in others, again, they came on rapidly. In some there is a history of a similar attack the previous year, or a yearly attack for three or four years in succession. Some will tell that they have been ill for several months, others that they have been ill for a week or two only.
Uncertain course.— The visitor will learn that this disease, which is beriberi, slowly or rapidly declares itself after an incubation period as yet undetermined but variously stated as of weeks or months, that it may be preceded by a period of intermitting languor, aching legs, palpitations, breathlessness, slowly advancing œdema of legs or face; or that the patient may wake up some morning and find that during the night he has become dropsical or paretic. Thus the disease may develop slowly or rapidly. Equally uncertain are its progress and danger; within a day or a week, or at any time during its course, it may assume fulminating, malignant characters. It may completely subside in a few days, or it may drag on for months. It may get well apparently and then relapse. It may, and generally does, clear up completely; or it may leave a dilated heart, or atrophied limb muscles with corresponding deformity. The variety in the severity, progress, and duration of beriberi is infinite; but in all cases the essential symptoms are the same— greater or less œdema, especially over the shins; muscular feebleness and hyperæsthesia, especially of the legs; numbness, especially over the front of the shins, of the fingertips, occasionally of the lips; liability to palpitation from cardiac dilatation, and to sudden death from the same cause.
Progress of the cases.— As the visitor watches the progress of the cases he will be astonished that those which he thought examples of locomotor ataxia, or of progressive muscular atrophy, or of ascending spinal paralysis, gradually improve, begin to walk about, and finally quit the hospital quite well. He will be astonished to see, after perhaps a profuse diuresis, the bloated carcass, that could hardly turn itself in bed, rapidly shrivel to little more than skin and bone, and assume all the appearances of the atrophic cases; and, later, perhaps after many months, to find the patient become rehabilitated, and, in due course, walk out of the hospital quite well. He will notice that the cardiac bruits come and go; that the degree of dilatation of the heart is subject to fluctuations; that what seemed confirmed organic disease completely disappears.
Cardiac attacks.— But he will also be astonished, as he goes his rounds, to see so often empty beds where the day before lay men whom he considered by no means seriously ill— certainly not dying. Some day he will come on a patient, whom the previous day he thought to be by no means seriously ill, actually in extremis. The poor fellow is propped up in bed, he is struggling for breath, his face is purple, his eyes are starting out of his head, his whole attitude is expressive of the utmost distress; he has a horrible, tearing, boring, crushing pain under his sternum and in the epigastrium; the vessels of his neck are throbbing violently, but his pulse is quick, small, intermittent, and his extremities are cold. In a short time the patient is dead. Some of the fatal cases, he Will note, die quite suddenly as if from syncope; but most die in the distressing way described, evidently from paresis and over-distension of the right heart, complicated and aggravated by œdema of the lungs, or by diaphragmatic paralysis, by hydrothorax, or by hydropericardium.
Nomenclature and classification of beriberi.— For purposes of description, the paralytic-atrophic cases are designated " dry beriberi " or beriberia atrophica; the dropsical cases, " wet beriberi " or beriberia hydrops; and those in which there is a combination of both conditions, "mixed beriberi." Sometimes the cases are classified according to the rapidity of development and gravity of symptoms into acute or pernicious, subacute, and chronic. None of these classifications is good, seeing that they all refer to what is clinically the same disease, and that one form may suddenly or more slowly merge into the other.
Etiology.— Sex, age, occupation, etc.— Beriberi attacks both sexes. Not uncommon in the breast-fed infants of beriberic mothers, it is rare in childhood and extreme old age, but occurs at all ages,*[2] its favourite age being from about 15 to 30. It affects rich as well as poor. It is confined to no particular trade or occupation. If anything, it has a predilection for those who lead a sedentary life and are much indoors, as students, prisoners, and the inmates of hospitals and asylums. It is apt to attack pregnant or parturient females. It is quite as common in the strong and full-blooded as in the weak and anæaemic.
Climatic conditions.— In countries in which there are a hot and a cold season the epidemic outbreaks occur during the former, old cases improving and new cases ceasing to crop up during the winter. In countries which are hot all the year round, beriberi may appear at any time; most frequently, however, in such climates it appears during the rains. Thus it resembles malaria in being fostered by damp, by high temperature, and, it has been said, by its most often attacking those who sleep on or near the ground. As with malaria, though its explosion in any given individual residing in the endemic area may be solicited by fatigue, chill, privation, and other causes of physiological depression, it is not actually caused by such circumstances. Unlike malaria, it is common enough in the midst of large cities, as well as in villages and jungle lands.
Influence of overcrowding.— Overcrowding and unhygienic conditions generally seem to favour the outbreak, or, possibly, the spread, of beriberi. This has, perhaps, a good deal to do with its frequency and virulence in oriental gaols, schools, mining camps, plantation lines, armies, ships.
Ship beriberi.— Unlike malaria, beriberi is common in the native crews, more rarely, though occasionally, among the European officers and sailors, of ships on the high seas and far away from any recent telluric influence. The crowding in the damp forecastle and the exposure incident to a sailor's life seem to be among the reasons, though not the only ones, for ship beriberi. Thus, this form of the disease is often seen at the Seamen's Hospitals at the Albert Docks and Greenwich among the lascars and sidi-boys of steamers trading to India, the disease appearing perhaps months after the ships have left the East, sometimes even months after they have been lying in the London Docks. Some years ago a number of these cases were admitted to the Seamen's Hospital at the Albert Docks. I had the curiosity to visit one of the ships from which several of the patients had been brought. I went into the forecastle. Although the weather was mild for Englishmen, it was evidently very cold for the half-clothed lascars. They had a tire blazing in their quarters, every door, scuttle, window, and ventilator of which they had carefully closed. The place was suffocatingly hot, damp, and redolent of steaming humanity. I do not know how many men had stowed themselves away with their dirty rags in this place, but there was a crowd of them. Several had symptoms of beriberi, and were in their bunks. After seeing the forecastle I was taken to a little dark cell, an oblong den with a couple of bunks one on top of the other, located somewhere in the neighbourhood of the keel. There was no light or obvious means of ventilation, and barely standing room. There I found three men sitting on the lowermost bunk, all of them suffering from severe beriberi. One of them, I afterwards heard, died before morning; the others were sent to hospital just in time, I believe, to save their lives. The fact is that some of these epidemics of ship beriberi occurring in cold climates are fostered, though they may be not caused, by the artificial conditions which the ignorant lascars are allowed to bring about. They feel the cold of the English climate so much that, on entering British seas, they try to keep their quarters warm by lighting fires and stopping up ventilators. By these means they create a hot, steamy atmosphere and a sodden state of the place they live and sleep in, which is a very good imitation of the tropical conditions in which beriberi is prone to develop. Although such unhygienic conditions favour the occurrence of beriberi, they do not suffice to produce it; as is proved by the well-authenticated circumstance that the disease is very common in the European crews of Swedish and Norwegian ships, which, as compared to British ships, are in far better sanitary condition, and yet beriberi is comparatively rare in the latter.
Asylum beriberi.— Not very long ago, exactly similar conditions to those above described, and with similar results, were conduced to by similar circumstances in the Dublin lunatic asylum already alluded to. This asylum, built for 1,000 inmates, had 1,500 crowded into it. Anyone who knows what the atmosphere of even a well-regulated and not over-crowded dormitory in a lunatic asylum is like can imagine what it becomes in warm weather, when three patients are lodged in a place barely sufficient for two. The heat, the breath vapour condensed and streaming down the walls, the effluvia from the patients, the closed doors, the barred windows, the want of air, and the damp conspire to reproduce the conditions found in the tropics; and it may be that when such conditions are reproduced elsewhere, even in temperate climates, the result will be just the same.
Although for a long time something had been known about the conditions predisposing to beriberi, it is only lately that anything like approximately accurate knowledge as to the causa causans of the disease has been attained. Many hypotheses had been advanced on the subject, some plausible enough if judged of in the light of the times, others manifestly absurd. It is unnecessary to refer at length to these exploded theories. Suffice it to say that their authors appear for the most part to have been dominated by the idea that for the production of a disease something in the nature of a germ or of a poison has to be introduced into the body; they overlooked the possibility of disease being brought about, not by the introduction of something foreign or abnormal to the body, but by the deprivation of something essential for its healthy nutrition. We now know that it is to the latter circumstance we have to look for the cause, or at least a principal part of the cause, of beriberi. Beriberi is a disease of "deficiency," to use the expression of Funk.
It is desirable, in view of the possibility of further discovery, somewhat to qualify this statement. It is just possible that the condition brought about by this deficiency merely predisposes to, or is necessary for the operation of, something else, perhaps an unknown germ which in the absence of this deficiency would remain inoperative even if introduced. Further, it may be that there are two or more diseases included under the term " beriberi," each of them acknowledging a different specific cause. Indeed there are not a few facts suggestive of such a possibility.
However this may be, thanks to the pioneer work of Eijkman, Braddon, Fraser and Stanton,*[3] we now know that the beriberi of the Eastern Peninsula, of the Eastern Archipelago, of the Philippines, of China and Japan is a sequel of a diet into which overmilled rice enters as the principal element, that is rice from which the entire pericarp and germ have been removed; and that in this pericarp and germ there is a substance essential for the proper nutrition of the nervous system of man and of many other warm-blooded vertebrates.
If a fowl be fed on paddi exclusively, that is rice from which the husk has not been removed, the fowl will thrive and very likely gain weight; but if it be fed on a diet exclusively of white rice, that is rice from which the pericarp has been completely removed, it will after a short time show signs of peripheral neuritis, lose weight, and, if the exclusive diet be persisted in, die with all the signs of a multiple peripheral neuritis. If a fowl which, in consequence of such a diet, has begun to show signs of peripheral neuritis be given regularly some of the polishings of the rice, that is the dust or remains of the pericarp, which had been removed in the process of milling,
fixing his attention on the remarkable and admitted fact that of the various races inhabiting the Malay Peninsula the Chinese are infinitely the most subject, the Klings (an immigrant Indian race) infinitely the least subject to beriberi, came to the conclusion that the excessive liability of the one race and immunity of the other are attributable to the difference in the way in which their staple food— rice— is prepared for the market. The Klings live on what Braddon calls "cured rice," that is rice which when garnered, and before husking, is boiled and dried. The Chinese use " uncured rice," that is rice that is husked without preliminary boiling. Braddon held that rice (paddi) is liable in certain localities to be attacked by a germ which in its multiplication produces a toxin, and that this toxin, which is not destroyed by cooking, is the cause of beriberi. The germ is destroyed by the boiling to which " cured rice " is subjected before husking; hence the freedom of the Klings from beriberi and the excessive liability of the Chinese. That there is no racial insusceptibility in the Klings is proved by their being attacked by beriberi when they chance to get imprisoned and are placed on the same food as their Chinese fellow-prisoners. These views received support from a carefully conducted experiment by Fraser and Stanton, who fed a gang of coolies on "cured rice" and another gang on " uncured rice," both sets of coolies being in other respects under apparently identical conditions, with the result that many of those 011 uncured rice sickened with beriberi, whilst those on cured rice escaped the disease. it will gradually lose the signs of neuritis, gain in weight, and recover. The neuritis— polyneuritis gallinarum, as it is called— is evidently the result of the deprivation of some element of food essential for the proper nutrition of the nervous system of the bird, and this element is located in the pericarp and germ of the rice grain.
The polyneuritis of the fowl is identical clinically and etiologically with the polyneuritis, called beriberi, occurring in man. For, as has been both accidentally and intentionally done, if the same experiment with rice-feeding is tried on man the result is identical —beriberi is induced. Thus, Strong and Crowell conducted a series of experiments on twenty-four life- sentenced prisoners, and were able to prove (a) the non-communicability of the disease and (b) its production in man solely by means of diet. Fraser and Stanton showed, and their observations have been abundantly confirmed, that the antineuritic element is located in the pericarp of the rice grain, that it is soluble in alcohol, is stable in acid but unstable in alkaline solutions, is thermolabile —being destroyed by a temperature of 130° C.— and that it is dialysable; that it is not a phytin nor a fat, and that, although itself not containing phosphorus, the amount of phosphorus in any given rice is a reliable indication of the safety, or otherwise, of that rice as a staple article of food. Rice containing less than 0.4 per cent, of P 2 O 5 they consider unsafe, and believe that its persistent use may lead to beriberi.
Acting on these findings, the Governments of Singapore and the Federated Malay States interdicted the use of white or polished rice in their gaols, lunatic asylums, schools, and hospitals, with the result that beriberi, which hitherto had been the cause of an enormous mortality and morbidity, has been practically banished from these institutions.Corresponding results have accrued from the same practice in Dutch Malaya, in the Philippines, and elsewhere.
It has been proved by Funk and others that the same or a similar antineuritic body is present in other cereals and in a variety of foodstuffs. It seems probable that the destruction by heat in the process of canning, or otherwise, of this body, called by Funk " vitamine " *[4]— which exercises a curative as well as a protective action may account for the prevalence of ship beriberi in Scandinavian ships, especially in long voyages during which such foods are an unavoidable necessity. In this respect there is a parallelism between beriberi and scurvy.
Morbid anatomy and pathology.— There is very little to be said about the post-mortem appearances in beriberi which is not covered by the accepted descriptions of the lesions of peripheral neuritis. There is a degeneration of the peripheral nerves more especially of their distal ends, and there is secondary atrophic degeneration of muscle, including that of the heart, which may be the subject of an acute fatty degeneration like that of diphtheria. Hamilton Wright has shown that degenerative nerve changes (formerly denied) may be detected in the nerve centres and throughout the implicated neurons, as in other forms of peripheral neuritis. This observer seeks to correlate the early or " acute " phase of the disease with the primary poisoning of the nerve-endings, the latter or " residual " phase with the stage of nerve degeneration. If there is anything peculiar about the post-mortem appearances in beriberi, it arises from the somewhat special implication of the central and peripheral organs of the circulation namely, dilatation of the heart, especially of the right side, and great accumulation of blood in the right heart and in the veins. In addition, there is a marked liability in many cases to serous effusion into the pericardium, pleural cavities, peritoneum, and cellular tissue. This very marked liability to serous effusion, and the tendency to cardiac dilatation, may be said to be more or less distinctive of beriberic as compared with other forms of multiple neuritis. The type of œdema indicates thai it depends especially on vaso-motor disturbances, although cardiac weakness and partial suppression of urine may be contributory elements. (Edema of the lungs also is not uncommon, and has, probably, a pathology similar to that of the connective-tissue œdema. There is no nephritis, The only lesion that might be considered specific in beriberi is the duodenitis, which, according to Hamilton Wright, is invariably present in acute cases during the first three weeks of the disease. The invariableness of this lesion is denied by other observers Daniels, Koch, and Hunter.
Mode of death.— The most practically important point in the pathology of beriberi is that which relates to the modes of death. The paresis and the atrophy of the voluntary muscles, the œdema of the connective tissue, and the serous effusions are, as a rule, not very serious matters at all events as affecting life. But it is very different when paresis and degeneration seriously implicate the heart and the muscles of respiration. In nearly all beriberics there is heart trouble, arising, doubtless, from implication of the pneumogastric nerve and the cardiac plexus. In some patients the degree of implication is slight; but in others it is sufficient so to weaken the heart that death is inevitable. We cannot be quite sure in which cases the implication of the pneumogastric nerve or cardiac plexus is likely to be serious, or in which cases it is likely to be slight. Often the mildest cases of beriberi, as judged by the degree of voluntary muscle paresis or by the amount of œdema, are in reality the most dangerous. There appears to be an element of chance determining the nerves which the poison picks out. Sometimes one may see a patient who is completely paralysed so far as legs and arms are concerned, and perhaps wasted to a skeleton; and yet this same patient may never have a serious symptom referable to his heart, or in any way threatening life. On the other hand, one may see a patient with very little paresis, very little œdema, and yet in a short time the heart may become involved, and he will die in a few minutes or hours.
I presume the dilatation of the heart, the usual cause of death, is favoured or brought about by a concatenation of several conditions: by degeneration of muscle fibre following nerve destruction, by imperfect systole in consequence of an interrupted nerve supply, by obstruction to capillary circulation in consequence of vaso-motor paresis in the pulmonary and general circulation. Once commenced, the cardiac dilatation tends to increase automatically; for the more the organ dilates the more difficult does it become for it to contract, the greater is the incompetency of the valves, and the more the blood stagnates in and over-distends it. The organ enters on a vicious pathological circle. Finally it becomes so distended that, like an overstretched bladder, it loses the power to contract altogether. The blood then rapidly accumulates in the great veins, the right auricle and ventricle are distended almost to bursting, and death is inevitable. The result is often contributed to by the coexistence of pleural effusion, hydropericardium, paresis of the diaphragm, over-distension of the stomach by food or gas, "and, above all, by oedema of the lungs. It can readily be understood how the establishment of any additional obstruction of this description would still further tax the dilated, enfeebled heart and determine the fatal issue.
When we come to make a post-mortem in these cases we may find a heart slightly hypertrophied and enormously dilated, the right cavities distended with blood, the lungs and liver full of dark blood, and all the great veins engorged.
Prognosis.— This tendency to dilatation of the heart is the dangerous element in beriberi; it should always be before our eyes, and dominate our plans of treatment. It is wonderful how rapidly it may come on, and how rapidly it may prove fatal. These sudden deaths, occurring sometimes from syncope—from instantaneous failure, as well as from the somewhat slower process of increasing over-distension— are constantly sprung on one in this disease. An absolutely favourable prognosis, therefore, ought never to be ventured on in even the mildest-looking case of beriberi, or so long as the patient is exposed to the conditions causing the disease, or so long as the neuritis appears to be active. That is a lesson which is often, and sometimes painfully, borne in on the practitioner in beriberi districts.
Evidences of grave heart implication, such as pulsating cervical vessels, equal spacing of the intervals audible on auscultation, enlargement of cardiac dullness especially to the right, epigastric pulsation, a rapid feeble pulse, a distended stomach, cold extremities, cyanosis, dyspnœa, and a disproportion in the strength of the heart- and wrist-beats, are significant of danger. Paralysis of the diaphragm, of the intercostal muscles, extensive serous effusions, very scanty urine are also unfavourable signs. Vomiting.— No one can say when or how soon fatal implication of the pneumogastric and other cardiac nerves may take place, but vomiting is always an ugly and threatening symptom in beriberi; it probably indicates that the former important nerve is being attacked. The Japanese regard the occurrence of vomiting as of fatal import. Marked dilatation of the stomach has a similar significance.
Prognosis is improved if the patient is placed on a non-beriberic diet and is removed (that is before the heart muscle, or the cardiac or respiratory nerves, are gravely degenerated) from the place in which the disease was contracted, to a healthy, non-beriberic, high-lying locality.
Mortality.— The mortality in beriberi varies in different epidemics and in different localities. On the whole, it is greater in low than in high latitudes, in the dropsical than in the atrophic forms, in the acute than in the chronic. In some epidemics it is as high as 30 per cent, of those attacked; in others as low as 5 per cent. , or even lower.
Diagnosis.— Usually the diagnosis of beriberi is not difficult. Multiple peripheral neuritis occurring as an epidemic, or in a place or ship in which the disease has occurred on some previous occasion, may as a rule be set down as beriberi. Sporadic cases may be difficult to diagnose, more especially if there is a history of alcoholism, of malaria, or of drugging with arsenic. The presence, actual or past, of œdema especially of œdema over the shins and palpitations and other evidences of cardiac implication, are significant of beriberi. It must be borne in mind that slighter degrees of beriberic poisoning, evidenced only by slight anæsthesia of the pretibial skin area, by slight œdema of the same region, by slight hyperæsthesia of the calf muscles, and, perhaps, by impairment or absence of knee-jerk, may be the only symptoms present. True rheumatism is rare in the tropics. Among natives, especially if their language is not understood, complaints of what may seem to be rheumatic pains in the legs should always be carefully investigated, the knee-jerks tested, and signs of hyperæsthesia of the calf muscles sought for. The significance of these signs of what may be described as larval beriberi is too frequently overlooked until some sudden death, which, with earlier recognition of the disease, might have been avoided, puts the practitioner on his guard. All paretic affections, all cases of œdema, all cases of palpitation, and all cases of rheumatic-like pains occurring among the natives of warm climates, therefore, should suggest the possibility of their being beriberic, and also the necessity for a detailed examination with this in view.
Treatment.— The first and most important thing to be attended to in the treatment of a case of beriberi is the diet. From this, rice, especially white rice, should be eliminated, and some article rich in vitamine— such as beans, peas, peanuts, barley, wheaten flour (not over-milled), or oatmeal substituted, and, in view of the fact that we as yet cannot be certain that beriberi is not in some way dependent on an unknown germ, the patient should be removed, if practicable, to some place away from the endemic spot, to some dry locality, if such is available. He should sleep well off the ground in a thoroughly ventilated, sunny room situated in an upper storey. He ought to clothe sufficiently and feed well, taking care that the food is of a varied and not of a bulky character, and that it contains a sufficiency of nitrogenous and fatty elements. Apart from other considerations, rice is found to be a bad food for beriberics; it is too bulky. Animal food, including fat, must enter into the dietary in reasonable amount. Milk and eggs are beneficial. Yeast is credited with curative properties, and extracts of rice-polishings, prepared in various ways, have undoubtedly a beneficial effect and, when procurable, ought to be given.*[5] The worst cases, particularly if there is any sign of serious cardiac implication, should remain in bed; but the mild cases had better spend the greater part of the day in the open air. If the disease break out on shipboard the dietary should be changed and the crew should be kept out of the forecastle, and, so far as possible, made to sleep on deck, properly protected from the weather by an awning.
With a view to diminishing to some extent the bulk of blood in the vessels and heart, the seriously affected patients should take little fluid, and keep the bowels very free by means of full and repeated doses of some saline aperient. In cardiac cases small doses of digitalis or of strophanthus seem to do good. Should signs of acute cardiac distress appear, full doses— three, four, or five drops of the 1 -per-cent, solution— of nitro-glycerine are indicated. The dose must be repeated every quarter- or half-hour, and kept up until the threatening symptoms pass away. In suddenly developed cardiac attacks inhalations of nitrite of amyl, pending the operation of the nitro-glycerine, may be given. It is well for these two drugs to be in the hands of properly instructed ward attendants, so as to meet cardiac complication on its earliest appearance. There is often no time to send for the doctor. Should signs of cardiac distension and failure persist and increase in spite of these means, there must be no hesitation in bleeding the patient, taking, if it will flow, eight or ten ounces from the arm, or, this failing for any reason, from the external jugular. Often, as the blood flows, rapid amelioration of the alarming condition sets in, and the patient is, for the time being, tided over an acute danger and given another chance. The bleeding should be repeated if the alarming symptoms recur, as they are almost sure to do. Oxygen inhalations, if available, are worth trying in cardiac attacks. Pleural and pericardial effusions
with good results. Under daily injections of cholesterin, polyneuritis avium rapidly subsided. If further experience confirm these results, we have in cholesterin a valuable remedy in our hands; further, the vitamine theory of beriberi will have to be revised. should be sought for, and, if deemed to be interfering in the slightest degree with the circulation or respiration, drawn off with the aspirator.
Provided the patient is placed on a suitable diet and has been removed from the spot where he fell ill, and provided he can be tided over the first fortnight, he will probably recover; but, on the other hand, should he persist in a diet of white rice and remain in the place where his disease was acquired, though he may get over one or two cardiac attacks, he will almost surely die.
In the case of breast-fed beriberic infants, they should be removed front the mother and handed over to a healthy wet nurse, or placed on the bottle. Sometimes this is impracticable; in such cases in the Philippines a preparation of extract of rice polishings, called " tiqui-tiqui," has the reputation of being wonderfully efficacious. It is given to the extent of 5 c.c. a day in 20-drop doses every two hours. At the end of 24 hours the most alarming symptoms disappear and the child is well in three days. If the case is a very severe one double doses should be given, and the tiqui-tiqui continued so long as there is any aphonia.
For the atrophy of the muscles and anæsthesia of the skin, faradization and massage are of service, and should be employed so soon as the muscular hyperæsthesia has begun to subside. Strychnine, arsenic, and nitrate of silver are in repute as tonics in these circumstances. Care should be taken that permanent deformity does not occur from contraction of muscles. Foot-drop should be counteracted by Phelps's talipes splint with an elastic accumulator, and any other threatened deformity appropriately met. Relapses must not be risked by a return to the original diet or source of infection. 'The seaside or a sea- voyage has often a marvellously restorative effect.
When beriberi breaks out in a school, jail, or similar institution the place should be emptied of its inmates as soon as possible; at all events, those parts of the building in which the disease has appeared ought to be cleared out, and not reoccupied until they have been thoroughly cleansed, disinfected, ventilated, and dried. Overcrowding must be strictly avoided. Ventilation must be effective. The dietary should be revised and, if necessary, rice should be eliminated; it may be replaced by meat, flour, or beans. All the inmates should be obliged to pass the larger part of every day in the open air; their knee-jerks should be tested, and their legs examined for numbness, œdema, and muscular hyperæsthesia from time to time. Any suspicious case should be removed at once.
Should beriberi appear on board ship, besides the precautions already indicated, on the assumption that there may be an infective as well as a dietetic element at the bottom of the disease, special means of disinfection must be employed. Rotten planking and bilge- water must be removed from the neighbourhood of the quarters of the crew; the sound woodwork should be scraped and painted; disinfectants should be freely and frequently employed, clothes and sea-chests washed and disinfected, and every means necessary to destroy lurking germs vigorously adopted.
In beriberi countries low-lying, damp situations should be avoided as building sites. The sleeping quarters, especially, should be raised well off the ground, and located, if possible, in an upper storey; all rooms should be so arranged as to be easily flushed with fresh air and flooded with sunlight.
As yet we know little of the virus of beriberi, if such there be, nor is our knowledge of the way in which it is acquired by any means complete. It may be communicable, and until we have more precise knowledge it is unjustifiable not to recognize the subjects of the disease as being possible sources of danger to others. Therefore, in the endemic zone, beriberics should be treated as infective and isolated. In gaols and similar institutions new-comers, whether manifestly suffering from beriberi or not, should be isolated and kept under special observation for a time, their clothes disinfected and body vermin scrupulously destroyed. Prison clothes and prison blankets especially should always be disinfected before being passed into store and before being served out. The utmost care should be exercised to keep prisoners free from vermin and the premises from flies, cockroaches, fleas, bugs,, and all insects that might possibly serve as transmitters of the hypothetical virus.
In institutions under Government control, or in conditions in which it can be successfully enforced, there should be a stringent rule against the use of over-milled rice. To legislate against the use of white rice in countries in which rice is the staple food would not be politic, and could only lead to opposition and defeat the object in view; but the authorities, by educative methods and in other ways, could do much gradually to eradicate any prejudice there may be amongst the natives against under-milled rice.
- ↑ * Dr. Strachan has described (Practitioner, 1897, p. 477) a form of multiple peripheral neuritis which he calls "malarial." The disease is endemic, and very common in Jamaica. It differs from beriberi inasmuch as it is not attended with œdema, is frequently attended with implication of the cranial nerves and is rarely fatal. We have no accounts of any similar disease from other tropical countries. Probably, therefore, Dr. Strachan's neuritis is not malarial, but depends on some cause peculiar, so far as known, to Jamaica. The subject requires further study.
- ↑ * The breast-fed child of a beriberic mother is apt to develop the disease. Hirota states that of 52 infants who suffered from beriberi while being wet-nursed by beriberic mothers 42 recovered, 5 died, 5 were not accounted for. In the cases which recovered the improvement set in at once on the children being weaned,
- ↑ * Eijkman was among the first to show scientifically that beriberi was connected with a rice dietary. He showed that prisoners fed on red rice escaped beriberi, and that those fed on white rice were exceedingly prone to the disease. Braddon,
- ↑ * " Vitamine " is a body allied to allantoin.
- ↑ * Chrisostem, acting on the hypothesis that beriberi is not a vitamine-deficiency disease but due to deficiency of cholesterin or similar compound in the blood, treated a number of cases with injections of cerebrin— six to ten on alternate days to the extent of 3 c.c. He claims remarkable results. Afterwards he injected 5 per cent, cholesterin in olive oil with even better results. Then he tried phytosterin (the vegetable equivalent of cholesterin), also