Dr. J. W. Anderson?The Study of Disease. 411

OBSERVATIONS ON THE STUDY OF DISEASE.

By J. WALLACE ANDERSON, M.D., Physician to the Royal Infirmary.

(Being the Retiring Address as Honorary President of the Royal Infirmary Medical Society, Session 1886-87.)

Gentlemen,?It has often occurred to me, lecturing in this very room to you on the Practice of Medicine, as controversial or obscure points presented themselves to our notice, that here was an interesting question for our Medical Society, or here again was a good subject for study, or field for argument and debate. Not that I would have you be mere wranglers, diligently discussing the different sfdes of a question, while the truth, unheeded, makes good its escape. I do not mean that. But we all know that discussion, properly conducted, means thorough searching, complete separation of part from part, that the whole be comprehended as well as it may. And I know that you can and will do this. But discussion, even for its own sake, must be a feature of such a Society as ours. You must take sides, Gentlemen. You must have it out with each other, for you cannot have it out with your teachers ; at least not till you have shaken the dust of these class-rooms and wards from off your feet, and then you will generously forget the past.

Last winter, Gentlemen, I heard that there were divisions among you. It was reported to me ominously, but I never knew exactly on what questions you divided. I may

presume, therefore, it was on some such points as these:? Is pneumonia a constitutional or a local affection ? Is it not a

different thing in the hospital to-day from the description you get in the class, drawn rightly enough in part from a past, and possibly a more robust age, than ours ? May it not be a name for a great many different maladies ? Is chronic rheumatoid arthritis after all a distinct disease from chronic rheumatism ? Is such a commonplace affection as lumbago of rheumatic character ? What about the identity of croup and diphtheria ? These are the kind of questions that, I suppose, you divided upon. At least, it is such questions as these that seem to me becoming to this Society, knowing as I do the energy, enterprise, and ability that are within its ranks. But it is not on any of these special questions that I mean

to address you to-night. I leave that for the class-room. I think it is my duty, as your Honorary President, rather to

412 Dr. J. W. Anderson?The Study of Disease,

suggest than to determine any particular line of inquiry. I would rather present to you, for your own further reflection, some views of disease that have been floating for a time

loosely in my mind, but which I have now brought together into some kind of shape ; some thoughts whose elucidation or controversion might be considered by you, amongst other things, suitable and acceptable work for the Society during the coming session. The first remark I would make is of an introductory

character. It is this. In all your study of disease endeavour to advance from mere details to general principles.

" Make

your acquisition of facts subordinate to the attainment of

general principles." * It is twenty years since I heard that from the lips of an old and respected teacher, who was long a manager of this hospital, the late Professor Allen Thomson.

I cannot remember if I even caught his meaning at the time, but I have often thought of his words since. Not that there is anything novel or original in the remark, but it is sound advice ; and there is such a show of details nowadays in our profession?I was going to say a shoal of details?there is such a show of details, chiefly in the way of case reporting, that we need to remind ourselves that there is something more than that to be done. Of course, we must have details

first, but we are not to rest content there. When we have tried our materials, then it is time to build. The whole is

greater than its part, not alone because it is greater but because it is complete. But I must illustrate my meaning. I suppose there is

hardly a disease, or at least a particular symptom of a disease, of which some one or other has not gravely remarked, that it is worse at night. Scarcely a week passes but one hears the observation ; usually it is one particular symptom, pain, that is meant. Once impressed with the weakness or the statement, I have observed it quoted of, I cannot say how many diseases. The last instance occurred not long ago when I was turning over the first leaves of a new surgical dictionary. Here I saw that a particular form of caries was carefully described as being worse at night, as if that were specially characteristic of the morbid process under consideration; and I believe in accordance with the spirit of the age, our medical age, this fact to which I have just referred has got its own special pathological hypothesis, by which its occurrence is explained in a highly satisfactory manner. And so a specific form of

* Introductory Address at the Public Opening of the Medical Session, 1867-68, in the University of Glasgow, by Allen Thomson, M.D., F.R.S.

Dr. J. W. Anderson?The Study of Disease. 413

rheumatism is commonly said to be more severe at night, as if that were characteristic of it alone. I am convinced it is not so. It would be much more significant, Gentlemen, much more interesting, if some one could point out to us a disease that is worse during the day. I except of course periodic diseases, which may be most severe at any time in the twenty-four hours. And we need spend no time over the explanation. It is

apparent enough that it depends, inter alia, on the general law that the vital energy is lowest between midnight and morning.

i3ut now, gentlemen, having your minds directed to that general law or principle, namely, that the symptoms of disease are apt to be most pronounced at night, it becomes an inter- esting and profitable study for you to search for its illustra- tions in detail. I shall give you one. It is a feature of such widely different diseases as idiopathic asthma and gout, that their early attacks, or still more a first attack, come on about the same hour, indeed with wonderful uniformity about the second or third hour of the morning. So does spasmodic largyngitis in children, or perhaps a little earlier, nearer

midnight. It is needless to multiply examples. There are

many that I could easily quote which are less common, but it is common things and common laws that I am speaking about. Obviously the main factor in the case is, as I have said, that from midnight onwards for a few hours the system is at its lowest ebb, and therefore most susceptible to morbid impressions.

Another illustration of a general law is the uniformity of our body temperature in health, and the uniformity in our surroundings which it requires. Or we might formulate it

thus:? Uniformity of body temperature a feature of health; variations in the external temperature a cause of disease. You observe I purposely take illustrations, that if you have not thought them out and expressed them in so many words, are yet so apparent that they are at once accepted by you. For you all know how wide is the range of temperature in the natural world, and how still greater extremes can be produced and measured artificially. Yet within what a narrow limit is the temperature of the healthy human body contained. Life is measured by a brief enough span as regards the thermometer; not much more than one degree. That is to say healthy life. We almost feel as if the thermometer had reduced the con- dition of health to a mathematical point. And the range in disease is not great between that of a death-like collapse and of a fever that, if continuous, will soon be fatal.

414 Dr. J. W. Anderson?The Study of Disease.

So, on the other hand, are variations of the surrounding atmosphere a cause of disease. We can withstand great extremes of heat and cold, one or other, if it is continuous and uniform. We cease to a great extent to feel that it is an extreme. We become familiar with it. But vary the one

with the other, change them suddenly, and we suffer. "Heats and colds," as our hospital reports have it, they are the fruitful sources of disease. Here again we see but a part of a still wider law, namely, that habit is an essential factor in our whole economy. That we are creatures of habit is a more thorough truism than is commonlv supposed.

There is a law which is worthy of our notice, one of limited action, however, and hardly entitled to be called a ' ' 1/

general law, and that is, the power of resistance in the human body to a lesser evil ivhen a greater assails. I think

my attention was first directed to this when, as a student of medicine, the picture of the asthmatic sitting at an open window, with his chest exposed to the cold winter air, perhaps for the greater part of a night, was sketched for us by our lecturer. The asthmatic does not take inflammation of his

lungs from such a procedure ; he does not even take a common cold. So, again, the amount of exposure to direct cold, and even to wet, that is safely borne in a case of severe haemor- rhage, where these agents are employed for its arrest, is very striking. I cannot bring to my recollection many very convincing examples of this law; but the immunity with which fever patients, as we see particularly in Continental

practice, may be immersed in cold water, is probably explained in the same way. There, it must be admitted, the explanation seems to be more obvious. The fever and the cold are simply antagonistic. .But in cases like the two first mentioned the

explanation, I think, lies too deep for us. Sir Thomas Watson accounts for these and similar phenomena by saying that " impressions which are unheeded are unfelt and inoper- ative but this, I think quite clearly, will only apply to the conditions of our animal life?i. e., the actions and sensations in which our intellect is or can be concerned. It will not hold true with regard to what I can only call our organic life. A

man will catch a fever quite as readily though he is unconscious of being exposed to the infecting particles, or get a lumbago though he was unaware of the draught at his back.

Leaving, now, illustrations of general laws or principles, I shall pass on to the consideration of some features of disease that you may think suitable for further study. The first I will put in the form of an antithesis, thus:?The weak point

Dr. J. W. Anderson?The Study of Disease. 415

in the organism; the special "point of attack in the disease. The more I reflect on our relation to disease, the more am I struck with its resemblance to a contest. Some of you have heard my opinion on the subject already, but not on this aspect of it. In all of us?however strong our bodies, however vigorous our constitutions as a whole?there is the weakest

point. It is not in nature to construct an organism of equal resisting power throughout, for nature is never perfect in detail. And we are, after all, only as strong as our weakest point; or, as the proverb has it,

" The chain is only as strong as its weakest link." You must have asked yourself the

question, Why does one man take a pneumonia, another a pleurisy, and another acute rheumatism, each brought about, we shall suppose, by the same cause?a thorough wetting ? The thorough wetting has struck at the weakest point. The

flaw, the taint, the idiosyncrasy is somewhere, and that is the weakest point. So much for the defence.

Against us we have not only special diseases, each with its own particular mode of action, but general diseases with their own special points of attack?the throat in diphtheria, the bowel in enteric fever, the kidney in scarlet fever, and so on. And special tissues too : in one disease the fibrous, in another the muscular, in a third the nervous textures. With such flaws in the armour, and exposed to attack on every side, the contest with disease is carried on.

I would now, Gentlemen, direct your attention to a point worthy of consideration in the investigation of disease, which we may best formulate in a way that possibly at first looks more like a catch than anything of real moment. It is this.

Different cases of the same disease may present very different symptoms; and very different diseases, necessarily in different cases, may present the same symptoms.

This proposition, whose truth a moment's reflection renders very obvious, is often forced upon our attention in the endeavour to identify or diagnose strictly a particular disease. We see the same disease taking, as it were, many an alias in the attempt to avoid detection, and a very different, and perhaps a very dangerous disease concealing itself under the cloak of one which, for the sake of the illustration, we shall suppose to be a comparatively trifling offender. Perhaps you will understand this better if I once more illustrate what I mean.

Take such a complaint as epilepsy. How greatly it varies in character and in degree. The attack may be severe and

prolonged, or it may be so slight as to amount to no more

416 Dk. J. W. Anderson?The Study of Disease.

than a momentary break in the line of thought. In its minor forms certainly, it appears under such a host of aliases that authorities have sought in vain for a satisfactory test of its genuineness. Loss of consciousness, as laid down by Reynolds and others, is probably as good as any, but we know that such a criterion will by no means include all its forms. As merely a momentary confusion of thought, or a slight tetanic spasm of a set of muscles, it may altogether defy detection till we get a hold of its associates ; till we find that it comes out of a bad

nest, to wit, insanity, or other forms of nervous disorder. So with regard to enteric fever. What a variety of types

it presents to our observation, and how utterly hidden it sometimes lies under a cloak of vague and conflicting symptoms. You look at the case and you know that it must be enteric fever or not that at all. If not that, it cannot turn into it, it cannot be half it, it must be something quite different, and yet you know it may be genuine enteric. You must be aware by this time that such forms are common in children, and might be absolutely beyond reasonable proof of identity, were it not that the fever is epidemic in your district; the undoubted cases in the adult proving the interpreter to the obscure forms in the child. Some, indeed, still believe in, and older writers have described, a distinct gastric fever; a fever which is not a mild enteric, but a different malady altogether. But I need not multiply examples. I feel sure that in your study of disease, you will find ample illustration of the first part of our proposition, that different cases of the same disease present many different symptoms, even to the extent of defying diagnosis.

.But the proposition loses whatever torce it has without its

second part, which we have yet to notice, namely, that

very different diseases may in different cases present the same

symptoms. Scurvy and purpura are a striking example of this. No two diseases could be more distinct than these: one clearly dependent on a certain dietic privation, the other in many cases, if not in all, defying any explanation. And

yet they may present almost identical symptoms. The history of medicine furnishes us with many examples of different diseases presenting similar symptoms, and being for ages con- sidered identical. Gout and rheumatism were thought to be the same disease till Sydenham proved the contrary: and

strange as it seems to us now, measles, small-pox, and scarlet fever, must have been at one time very imperfectly, if at all separated. So, as you are aware, have typhus and enteric fever been quite recently distinguished. All this has been

Dr. J. W. Anderson?The Study of Disease. 417

effected by remembering, consciously or unconsciously, this second part of our proposition.

I have long believed that pneumonia is but a term for

several diseases of like symptoms. We have the old classical

form, essentially non-catarrhal, sometimes epidemic, some-

times, it has been thought, infectious. Without being too

speculative, we may suppose it possible, or even probable that two distinct diseases have been included under the one name, one infectious, the other not. In more recent times the catarrhal form has been well recognised, while unquestionably there is a traumatic inflammation of the lungs, so closely resembling the idiopathic form that its distinctive features afford us still an interesting field for further study.* In fine, I think pneumonia is a term that includes several different

diseases, which have in common, certain well defined symptoms and signs.

Whether you consider this comes within the scope of

practical medicine or not, Gentlemen, I venture to think that while you employ an odd leisure hour in puzzling yourselves about the nature of some obscure medical disorders, the pro- position to which I have been directing your attention will

recur with some advantage to your memory. For it will not do to say that a disease is recognised by its symptoms alone. They may be equivocal, but the disease cannot be. And while, after all, the best may be baffled, he who can take the widest view of all the past history, and of the whole present condi- tions bearing upon the disease, will be the one who will arrive nearest to the truth.

I have said all the past history and the whole present conditions. Do we sufficiently consider what these words mean ? I am going to bring my observations to a close by indicating what they mean. You will often find yourselves sorely exercised over the

exceptional course or the unexpected turn that an apparently simple disease takes. You are called to see a man who, though he is only forty-five years of age, is evidently past his best. There is some pulmonary mischief. He has not a very high temperature, little pain, and a non-characteristic spit. There is little or nothing in the account he gives of himself to

explain why he is ill at all. On examination you find slight dulness of the chest wall over by no means a wide area and unilateral, and a not very characteristic pulmonary rale. But

he dies when many a patient with more pronounced acute * I have considered this question from another standpoint in a paper

on "The Specific Origin of General Disease."?Lancet, 2nd May, 1885. No. 6. 2 E Vol. XXVIII.

418 Dr. J. W. Anderson?The Study of Disease.

disease recovers. Or, again, your patient, who has been

getting gradually worse, has at length extreme dyspnoea, precordial oppression, general dropsy, cyanosis, and by and bye delirium. You know that both heart and lungs are

grievously affected; but he does not die, at least not yet. It is impossible he can recover; but he rallies again and again before he falls in the unequal contest. Why do these cases run a course so unlooked for ? Not so

different a course ; that is simple enough. But why did the first die when we think he should have recovered, and the second return again and again to the encounter, as if he mocked at death ? Where is our science, where the resources of our art, that we cannot explain this '{ Such thoughts, 11 doubt not, will often cross your minds. Gentlemen, if we | knew all the past history of each case, it would be simple enough. We may not need to go back very far. In the first

case, it may have been a constitution weakened by excess. No; he was a temperate man. You try again, and you find his work was not of a specially injurious kind. At last you discover that the excess was overwork. Or it may have been no work, and the natural consequence, privation. The man has been starved. But after we have exhausted our inquiries and failed, are

we to reproach ourselves ? Have we, can we have, the whole

past history ? Can he tell us every event of his life; and if he could, could we appreciate the significance of each ? And the other man. Why did he not die when you

thought he would ; when all your experience led you to think he would ? Why was he able to contest inch by inch and even gain an advantage, though, alas, only temporary, against such overwhelming odds ? Here, again, we would need his whole history. We enquire into every detail, and find his life was well ordered. But, perhaps, even it was not all it might have been. We go farther back and we find that his parents bequeathed to him the best of all inheritances, a faultless constitution. The malady had been repulsed by the inherent vigour of the constitution.

I hope, Gentlemen, I am giving a sufficiently practical conclusion to my remarks by impressing these things upon you. You will find many examples of such puzzling, contra- dictory cases, as it were. Remember there must be an

explanation somewhere, and I have been showing you one way along which you should seek for it. I have long thought, and some of you have often heard me teach it, that the most practical question, a vital question, for us in a case

Mr. Maylard?Swprci-Pubic Cystotomy. 419

of pulmonary consumption, is?Has it been induced or is it inherent ? Has it been induced by adverse extrinsic con-

ditions, or is it from an inherent depravity of constitution ? In nine cases out of ten that will be the main element in the

prognosis, and in the exceptional instance will only be second in importance to the particular stage at which the disease has arrived. In hospital practice you more usually find that the mischief has been forced upon our patients by their unhappy lot. Give them rest and food. Give them a chance of life, or let them give themselves a chance where the fault has been greatly their own, and they will do well. They will recover, when the rich, on whom the disease has fallen in spite of their wealth, will not be rescued by all the resources their wealth can command.

Gentlemen, I have made my observations as your Honorary President. I trust there will be one still left to me to

make as your friend, and that is, that I may observe you in

days to come pursuing an honourable and successful career, with ever a warm corner in your heart for the old Society, the old teachers, and the old school.