9. Acquired Scrofula.—Although in perhaps a majority of all scrofulous cases the diathesis has been inherited from the parents, the fact cannot be too strongly emphasized that in a large number of cases the disease may be developed de novo, independent of such heredity. To scrofula developed from the influence of bad ventilation and overcrowding, absence of sunlight, insufficient, bad, or unsuitable food, cold and damp, imperfect clothing—in short, all those conditions associated with poverty, squalor, and ignorance—Grancher has well applied the term la scrofula a miseria. And it is only by a clear comprehension that scrofula may be, and often is, developed under these conditions that the medical profession in general, and municipal health authorities in particular, may be induced to teach and enforce upon the poor both the knowledge and the practice which may prevent it. Even in the open country, where there is at least no lack of pure air and light, the lesson can be enforced with equal profit; for the children of the farm-laborer are likely to be imperfectly and improperly fed, and lodged in apartments at night that in the matter of foul air and filth could not be well surpassed in the purlieus of the dirtiest and most overcrowded city.
EXCITING CAUSES.—The actual exciting causes of scrofula when the diathesis already exists are too numerous to be mentioned in detail. Indeed, almost any trivial injury or inflammation, any disease which has produced a temporary cachexia, may rouse into activity the perhaps hitherto latent tendency. How often do we see a slight blow upon the knee-joint produce a white swelling which lames for life the heretofore healthy and active boy or girl! A fall upon the hip which was almost unnoticed at the time excites a coxalgia which either destroys life or renders the child for life a cripple; or a slight jar of the spine induces a disease of the vertebræ which, if recovered from at all, produces a terrible deformity. A slight eczema of the face or scalp or a catarrh of the mouth or throat will excite that slow and generally painless enlargement and induration of a neighboring lymphatic gland which always ends in its caseation and final destruction by suppuration. A slight injury to the periosteum may excite a destructive caries or necrosis of the underlying bone, and a temporary catarrh of the intestines a tabes mesenterica with all its fatal consequences.
Speaking generally, it may be said that anything that produces a local disorder of nutrition or impairs the health generally of a person predisposed to scrofula is sufficient to bring about some manifestations of the disease. They are especially apt to follow the eruptive fevers. Measles and scarlatina are very commonly arousers of the scrofulous process, not only by the temporary impairment of health which follows them, but also through the catarrhs which are usually present in both diseases. Vaccination has often been accused of imparting scrofula; and, although this is untrue, since scrofula cannot be imparted in the sense of transference from one person to another, there can be no doubt that the predisposition may be roused into activity by the slight impairment of health associated with vaccination or by the slight injury inflicted at the point of introduction of the vaccinal virus. In some cases the disease has manifested itself for the first time during pregnancy or lactation, and there is no doubt that in cases where the disease has existed in childhood these conditions often cause it to reappear. In conclusion, it must be said that many cases apparently occur spontaneously—"the disease came on of itself"—or if there are any exciting causes they were so trivial as to have escaped notice altogether.
Finally, it must be remembered that the eczemas, catarrhs, ophthalmias, otitis, chilblains, erysipelas, and numerous other local disorders of nutrition which are often the causes of graver manifestations of the disease, are themselves very prone to run a peculiar course characterized by chronicity and intractableness; and many regard these disorders as themselves manifestations of scrofula. Indeed, Virchow, basing his argument upon the fact "that scrofulous enlargement of the lymphatic glands of the neck often follows upon certain diseases affecting the throat, such as mumps, diphtheria, and scarlet fever, maintains that scrofulous proliferation of these glands, like ordinary inflammatory hyperplasia of the same organs, is always secondary to some peculiar process going on at the mucous surface or other part which is in direct relation with them by means of the lymphatic vessels; that scrofulous disease of the glands of the neck is traceable to some inflammatory condition of the throat, fauces, or contiguous parts; of the bronchial and mediastinal glands, to pulmonary or bronchial inflammation; and of the mesenteric and retro-peritoneal glands, to similar conditions of the alimentary canal. But he considers that there may be some special element or quality in the primary inflammation, and a tendency in its products to undergo rapid decay similar to that which characterizes the morbid products of the diseased lymphatic glands, but that generally they are not recognizable, from the fact that in this case the cells are mostly developed at a free surface, and are speedily shed from it." He admits, however, "that there may be some special aptitude or weakness, congenital or acquired, in the lymphatic glands of certain persons, or of certain parts of them, which makes their inflammations, induced by indifferent causes, assume the scrofulous character."6 From the last of these propositions no one will be likely to dissent, but that there is "some specific quality or element in the primary inflammation," etc. few will be inclined to agree. There is nothing peculiar in the eczemas, ophthalmias, catarrhs, etc. spoken of, except that they occur in persons possessing the scrofulous diathesis; and it is this alone that gives them their special characters, if there are any. In other words, we cannot say that these disorders occur in certain children because they are scrofulous, but that they are specially intractable on account of the scrofulous diathesis upon which they are engrafted. Millions of children have catarrh and ophthalmia (indeed, few escape these disorders throughout the first ten or twelve years of life) who never show any other evidence of the scrofulous taint; and nearly all have measles and scarlatina, but it is only the scrofulous who usually suffer severely from the secondary effects of these diseases. But they do not have measles or scarlatina because they are scrofulous, and we can with no more justice say that they have catarrhs or other inflammations because they are so. We do not believe, therefore, that strumous children have cutaneous and catarrhal inflammations simply because they are strumous; and if we speak of scrofulous catarrh or ophthalmia or eczema, we use the terms in the same sense as when we would speak of a scrofulous measle, scarlatina, or whooping cough.
6 The Theory and Practice of Medicine, by Jno. Syer Bristowe, M.D., 1879, pp. 80, 81.
Although we have few reliable statistics bearing upon the question, it can scarcely be doubted, judged by the results of casual observation, that scrofula is much less frequent in America than in Europe, and that in the latter there is less of it than formerly. The cheapness of land in America has prevented that excessive overcrowding that exists in the older and more densely populated countries, and the abundance and cheapness of animal food has prevented that excessive feeding on bread and potatoes which constitutes such an important factor in the production of the scrofulous diathesis in some other countries.
PATHOLOGY AND MORBID ANATOMY.—The most important and central anatomical and pathological facts both in the causation and progressive development of struma, according to the writer's views, are—
1st. That faulty anatomical—or rather histological—construction of the tissues of the scrofulous individual already alluded to as having been first brought to the notice of the profession by Formad of Philadelphia, which consist of an unusually large number of lymph-spaces (which are also unusually large), and consequently an excessive number of lymph-vessels and lymph-glands.
2d. Excessive production of rudimentary lymphoid cells, and probably also of lymphatic tissue.
3d. Diminished and insufficient number of the capillary blood-vessels; and, as a necessary consequence of these,