process of the skin is accompanied by coincident processes of the alimentary and urinary tracts, and interference or interruption of the process in the skin is accompanied by similar interruption of the internal process. For example: In the eruption and sequela of scarlet fever and measles. In interrupted elimination in exanthematous disease we have products of infection left in the tissues, and it is in such cases that renal and other visceral affections occur. These have been held to result from the additional elimination imposed on the kidneys, lungs and intestinal canal, through insufficient excretion of the skin. The immunity of the lower animals to syphilis prevents demonstration of the infectiousness of the products of desquamation and makes the argument necessarily a logical inference as to resemblance in behavior to the exanthemata in many respects.

While no accurate or general comparison can be drawn between syphilis and the exanthematous diseases, there are certain marked points of resemblance which cannot be overlooked. Each is infectious under certain differing conditions. A single attack of each as a rule confers immunity. Each has periods of incubation though varying in length. One is acute and the other may be and generally is chronic. Yet many cases of syphilis end with the secondary stage when untreated and most cases when properly treated show no lesions after that stage. The exanthematous nature of the eruption thus shown establishes a similarity, within limits, which HUTCHINSON assumes between syphilis and variola and scarlatina. But without further pursuing the questions of etiology and pathology of these diseases which have marked points of resemblance, as of difference, may not the analogic argument hold good as to treatment? In the true exanthemata we regard the eruption as eliminative and endeavor to promote it, and the laity, as well as the profession, understand that an incomplete or prematurely receding eruption is unfavorable, whether it be a cause or a coincidence. The products of desquamation in these cases are infectious, the crusts of variola especially so, and it seems a rational view that the efflorescence of the skin which marks the generalization of syphilis may be to a considerable extent an eliminative process. But whether the destruction of the syphilitic bacillus and the cure of the disease is accomplished by the process of phagocytosis and resistance, or antidotes by mercurial disinfection of the tissues; or the virus or its ptomains eliminated through all the channels of excretion, I believe it will be agreed by physicians having the largest experience in treating syphilis, that a free and pronounced eruption occurring at about the average period is regarded as a favorable symptom. Not alone because it makes clear the diagnosis and indications for treatment, but because clinical observations show these cases, other things being equal, to be more amenable to medication and to run a more uniform and uninterrupted course to recovery.

If this course, which clinical experience has shown to be most successful, is also in line of natural effort, and aids and is aided by elimination, particularly through the skin, the method should still further commend itself to general practice; and physicians, and patients intelligent enough to understand, may more readily see their way to defer active specific treatment, until a stage when the situation is clear; when no harm will result; and when there is an almost certain prospect of doing good.

The discovery of the syphilitic bacterium and antitoxin may change by demonstration much of what now is somewhat speculative.

PREDISPOSING CAUSES OF PULMONARY TUBERCULOSIS.*

BY DONALD S. CAMPBELL, M. D., DETROIT, MICHIGAN,

[PUBLISHED IN The Physician and Surgeon EXCLUSIVELY)

I FEEL almost like apologizing for presenting this paper tonight, as the subject matter of it has been so freely and so exhaustively discussed by various prominent pathologists throughout the civilized world, especially within the last few years, that apparently nothing new can be brought forward to enable us to better comprehend the chief underlying causes predisposing the development of acute pulmonary tuberculosis. Indeed it would appear in attempting to discuss any one of them, that it would be like threshing over old straw to garner a few grains of facts for future preservation. However, be that as it may, we have acquired as well as inherited causes which have in a great measure been ignored, chiefly by an overzealous profession, in trying to mitigate and combat by every known process, real and speculative, the proliferating qualities of the tubercule bacillus, without attempting to deal directly with the prime factors which lower the vitality of the very agents that grant us immunity to the disease. By saying this, I do not belittle the efforts put forward by state and local boards of health, as well as by the general profession, to stay the advance of tuberculosis; for great good has already been accomplished in combating it, and much more can be achieved in the same line by the aid of the state and the individual; for by these agencies we are better equipped to cope against its spread in those not blessed with immunity. But should we lose sight of the physical conditions which favor the development of the tubercule germ? Are not other etiologic factors at work by forming infective centers or foci for the development of phthisical disease? And if immunity is but feebly granted to such as are under the ban of specific infection, or any of its kindred diseases-whether inherited or acquired—what influence can be instituted to limit this condition? These are the burning questions which have been uppermost in my mind for several years—the very ones on which hinge the practicabilty of controlling pulmonary consumption.

Since it is the purpose of this paper to deal directly with the chief predisposing causes of pulmonary tuberculosis, and not with the invasion nor the virulency of the tubercule bacilli which we all respect, let us inquire into the principles which, tend to induce a low and unhealthy state of the constitution which, from any exciting agent, favor the development of tubercular disease, before an attempt is made to answer the above question.

Strictly speaking, everything which induces poverty of the blood, or impairs the nourishment of the body has been considered a cause of consumption. This includes, without defining them here, the deficiencies of all the essentials which go to maintain a healthy being. Indeed, we cannot but deny that anything which depresses the nervous system and causes great drain upon the vital organism tends to greatly encourage phthisical disease. But we can deny that this statement includes the whole truth; for there are usually other etiologic factors or precedent conditions which appear to be necessary to produce this result. Now, what is this dyscrasia-very marked in delicate constitutions but latent in others-which limits the powers of immunized action toward checking the growth of tuberculosis? It is sufficient to say that it is of inherited origin. Though its real nature is beyond our present knowledge, and

*Read before the DETROIT MEDICAL SOCIETY.

though it may never disclose itself by outward signs, it frequently makes its appearance in early childhood and in adult life, especially at the time of puberal development, in the guise of scrofula. This condition of undoubted inherited influence is a distinct affection of unknown origin. Though I believe after careful observation, and from the concurrent testimony of all times, that not only is it more closely associated in all its pathologic aspects to inherited syphilis than to the results of any of the other ascribed influences, such as impure air, poor food, damp dark dwellings, cold damp climate, or through the sequelæ of severe diseases, as typhoid fever, measles, pertussis, scarlet fever, or any other disease which might terminate in a scrofulous habit, but that it is the chief cause of the condition known as scrofula or the disease itself only modified through one or more generations by nature's grand process of gradual elimination, or attenuation in raising the curse. Therefore, I consider this inherited diathesis chiefly of syphilitic origin, which has been transmitted in families through generations until it has lost its specific infectious nature, and assumed another form under the nom de plume of scrofula or king's evil. I believe, then, that syphilis blended into this unknown quantity is the chief predisposing cause of both pulmonary and general tuberculosis; and though it might pass from one generation to another unnoticed, it usually unmasks itself before then, generally just prior to or immediately after puberty, in the role of a cachexia, or a condition in which the system of nutrition is depraved. This is marked in those of delicate constitutions who are prone to chronic diseases, especially bronchitis, pleuritis, tonsilitis and enteritis, on the slightest exciting influence.

As an example of this hereditary specific influence, which bears upon the point at issue, let me briefly mention a family of my personal acquaintance which has suffered very severely thus far into the second generation. The male grandparent, strong and healthy, and of a healthy pure family, without a blemish or taint of any disease, contracted syphilis about six months before his marriage to a lady of refinement and purity, whose parents also were physically and mentally pure and healthy. He relied, as he told me a few years ago, on his physician's judgment that he was cured, and could not possibly inoculate his wife, nor even transmit it to his offsping (should he have any). This apparently was true in his case, for he never has shown a blemish of it from that day to this, a period covering more than four score years. About six weeks after marriage his wife showed evidence of the secondary form, but it speedily succumbed to radical treatment, before she was aware of its true nature. They had five children. The first died at seven months from pustular syphilodermatitis, but under the cloak of scrofula; the third and fifth lived to about the puberal period in good health, when they died from galloping consumption, or what we would call acute miliary tuberculosis. The second and the fourth passed through puberty unscathed from pulmonary or any other disease, but both are of rather delicate constitution. The fourth is unmarried, very delicate and prone to nasal, laryngeal and bronchial catarrh, and shows evidence of this cachexia in the premature destruction of her teeth. The second married into a strong healthy family, and had two beautiful but delicate children. One died at the age of five from tubercular enteritis; the other at eleven from cerebrospinal meningitis, but from the history of the case then given it was undoubtedly of tubercular origin.

I cite this family not merely to show the depravity, nor the insidious nature of syphilis, nor the ignominy of its curse, however innocent the person may be who contracts it, but to afford conclusive proof from clinical evidence, that it is inheritable, and that it is more than likely to be the chief predisposing cause of tuberculosis, by a gradual process of evolution or transformation into the scrofulous condition. I could cite a number of other similar cases that prove the law of this heredity, but this would be superfluous.

Now, how far this constitutional influence extends before disclosing its symptoms, cannot be accurately determined; for usually after passing through the first generation, it has lost its pathologic significance. But any observant physician who has had abundant experience knows that though its specific nature may be removed its inherited influence passes intact through generations; and that its final disposition is to attack the lymphatic glands and to depress the power of resistance to external influences previous to any tubercular deposit, thereby producing the condition known as strumous disease. This inherited product is one of the chief predisposing causes of pulmonary tuberculosis. It is the superstructure on which the tubercle develops when the tissues become weakened by the slightest inflammatory action, whether it is the offspring of syphilis or not. In other words, the scrofulous condition is a constitutional disease of a specific hereditary origin, though in some cases it may be acquired; while tuberculosis is a germ productive agent of a contagious or infectious nature, depending greatly upon the supply of the infective matter of scrofula for its development. We are aware, without relating here, that this diathesis, is exceedingly prone to certain diseases, especially to inflammation of the mucous membrane of the air-passages, on the slightest exciting influence, and that their products, being abundant in proliferating cells and abnormal in character and readily absorbed by the lymphatics, are apt to produce secondary inflammation and enlargement of the bronchial, pulmonary and mediastinal glands, and that if their secondary inflammatory products are not reabsorbed in time they become caseous, and thus form the infecting foci for the development of pulmonary tuberculosis. This is true also of the various glandular structures of the body, especially of the lymphatic glands of the mesentery. No doubt this constitutional debility is produced by other causes also, especially when syphilitic history is absent. We are compelled, then, to trace its origin to other sources, though I look upon them only as accessory acts of the original virus. Intermarriages, very early marriages, advanced age of a parent, close confinement, imperfect ventilation, lack of fresh air, constant residence in a humid atmosphere, insufficient or indigestible food, intemperance, any interference with the development of the chest or body, the sequelæ of previous diseases, long continued dyspepsia, prolonged lactation, excessive sexual indulgence, undue mental labor, and depressing passions, are all classed as predisposing causes of tuberculosis, through their depressing influence on the general system. But I have grave doubts whether any one of them is capable of transmitting its acquired dyscrasia, for it does not contain any of the specific elements, which are so essential to produce the scrofulous cachexia; but both are prone to the development of the tubercle; they both destroy the immunizing function of the healthy organism. The former is never under the ban of the specific virus and I believe cannot be transmitted, whereas the latter is

purely constitutional, and depends upon the syphilitic virus entirely, for its transmission.

The contagiousness of tuberculosis must, then, depend on one or the other of these conditions. I do not think it is possible for a healthy person, born of healthy parents, to contract tubercular disease, unless he acquires a dyscrasia through prolonged sickness or personal abuse. If this were not so, we would all be in an alarming plight, for practically speaking, we are surrounded on every side by these pathogenic microorganisms; the air we breathe, the food and drink we partake, and the clothing we wear, may be loaded with them. Every person in a large community like this, is at all times more or less exposed to the tubercular contagion. We cannot escape its influence, try as we may, for every reputable physician knows that tuberculosis is a very prevalent disease among us. We hear of it on every side. In its advanced stages we find it confined in the home; in its incipient form we find it in the church, the school, the theatre, in fact in every place of public ineeting, even in the store and the workshop, so that really no one can dodge its contagious influence, try as he may; and unless shielded and protected as we are by the inherited principle of immunity, which is constantly offering resistance to the encroachments or invasions of this disease, we would all be under its ban and sooner or later perish. It is to the integrity of these inherited principles, coming down to us through generations unimpaired by any specific virus, that we owe our safety. To protect and strengthen those constitutional safeguards by every legitimate means possible, against the ravages of tuberculosis, is the only hope, the only solution for staying its advance in future generations. In my mind this is the only rational plan by which it can be controlled.

Now, what about this parent of scrofula? Let me quote the col-' lected opinions from a few of the eminent physicians of the immediate. past and the present, based chiefly on their clinical observations, though authors in general barely allude to them. NEYMIER considered syphilis as the basic principle of all scrofulous lesions. ROBERTS believed syphilis tended to influence its development, which in turn produced the soil favorable to the growth of the tubercle. HUTCHINSON, one of the keenest observers living, having had vast experience at London Hospital, traced many chronic skin troubles of scrofulous origin directly to it. SIR MORELL MACKENZIE, although he never connected syphilis with the development of scrofula in his work, spoke frequently about it at his nose and throat clinics. He fully believed that this dyscrasia had its origin in transmitted syphilis, and that it was closely related to laryngeal tuberculosis. While I was a student under him, he told me, on inquiry, that he could very frequently trace the scrofulous tendency to the syphilitic; but the great difficulty of proving this relationship was that pathologists could not connect the one with the other, although they firmly believed from the abundance of clinical evidence furnished, that it did exist. GRAINGER STEWART, of Edinburgh, contended that the scrofulous condition is in a great measure closely related to inherited syphilis. FLINT, PEPPER and LOOMIS construed the true origin of scrofula, but evaded its significance in their respective text-books. The last, I know, was a firm believer in the capabilities of its transmission; for during 1884 and 1885, while receiving instruction at his private clinics, I frequently heard him discourse on its hereditary nature. He contended that scrofula is one of the chief predisposing causes of pulmonary tuberculosis; and that the