Page:Encyclopædia Britannica, Ninth Edition, v. 18.djvu/427

PATHOLOGY 405 probably had its origin, namely, the reparative process in inveterate or neglected ulcers of common and every -day origin, but with a contagiousness of their own, and with a certain infectiveness of their own towards the adjoining tissues and the nearest packet of lymphatic glands. The most characteristic form of the generalized syphilitic infec tion, which may not manifest itself for several years after the reception of the virus, is a nodular or infiltrating new growth in various organs in the liver, in the testes, in or upon the brain, in the muscles (tongue and jaw -muscles especially), in the peri osteum, and in the lungs. These nodules are called gummata from the somewhat tenacious, firm, opaque brownish appearance of the fresh-cut surface. The structure, where its vascularity is perfect, consists of small round cells lying mostly in rows among thin fibres, and it closely resembles granulation - tissue, only that the cells are smaller and the intercellular substance (fibres) harder or denser. Molecular death, or ^necrosis, overtakes this new forma tion at various central points, owing to the inadequacy or suppres sion of the blood-supply. One of the most remarkable features of the process is the enormous overgrowth of cells in the inner coat of the arteries within the affected area, leading to an accumulation of elongated cells and intercellular substance, which may even obliterate the channel of the vessel altogether. Over the later products of syphilitic infection, both the nodular and the infiltrated, there are two drugs, mercury and iodide of potassium, which have a remarkable power, causing their absorp tion and conducting the infective process to a safe issue. Syphilis has been compared by Hutchinson to a very prolonged fever, with its stages separated by intervals of months ; like a fever, it burns itself out, so that a time comes in the course of years, if the patient have not succumbed to the effects, when the system is practically free of the virus, just as it is free of the virus of smallpox in three weeks. In a certain proportion of cases only the secondary symp toms occur, and not the tertiary, the virus having presumably exhausted itself in the earlier manifestations. In the syphilis of the offspring it is necessary to distinguish two classes of effects. On the one hand, there are the effects of general intra-uterine mal-nutrition, due to the placental syphilis of the mother ; and, on the other hand, there are the true specific effects acquired by inheritance from either parent and conveyed, along with all other inherited qualities and tendencies, in the sperm- elements or in the ovum. These two classes of effects are com mingled in such a way as not to be readily distinguished ; but it is probable that the erroneous growth of bone, at the epiphysial line in the long bones (sometimes amounting to suppuration), and on the surfaces of the membrane-bones of the skull, is a result of general placental mal-nutrition, like the corresponding errors of growth in rickets. The rashes and fissures of the skin, the snuffles, and such-like well-known symptoms in the offspring of syphilitic parents are to be counted among the true mimetic effects of the specific taint ; so also the peculiar nuclear overgrowth in the sup porting tissue of the liver, the interstitial pneumonia alba of the lungs, and the like. As in rickets, it is in many cases some months after birth before the congenital syphilitic effects show themselves, while other effects, such as interstitial keratitis, the mal-formations of the permanent teeth, and the rarer occurrence of laryngitis, come to light during childhood and youth. Injury to a syphilitic child is apt to have unusual consequences ; thus a blow on the arm may be followed by a gummatous growth in one of the muscles. nrcle Tubercle and Scrofula. Tubercle and scrofula are among the i ;cro- commonest and most fatal diseases of mankind. No chapter in il pathology has a more pressing interest ; none is surrounded by so much theoretical difficulty, or concluded by so much practical failure. It is not only in Europe, but in America and the British colonies, as well as throughout the whole inter-tropical zone, that this remarkable wasting disease is found. The most considerable degree of immunity is said to be in Iceland and on the Asiatic steppes. While the mortality from this disease is very great, in some European countries amounting to one-seventh of the death- rate, and that, too, among the youth and flower of the people, there is everywhere evidence that a very much larger proportion had incurred a slight degree of the malady and had survived it. Nothing is more common in the course of post-mortem examinations than to find traces of " obsolete tubercle " in the lungs and lymph atic glands. Cohnheim recalls with some approval a saying that used to be current at Greifswald, that almost every one proved to have been " a little bit tuberculous " ; and Rindfleisch bases his pathology of the disease on the assumption that a tuberculous dis position has become practically universal throughout the human stock, so that inflammations, under certain aggravated circum stances, may light up the disease in almost any one. It is peculiarly common in prisons, barracks, and workhouses ; and, in the last- mentioned, tubercle and scrofula are not rare among the aged. There are instances within the knowledge of most people where the marriage of first cousins, and still more certainly of double cousins, has been followed by a very pronounced consumptive tendency in the offspring, even if there had been no very clear history of con sumption on either side before. No disease runs more in families than tubercle. While there arc all these evidences of a widespread constitutional liability to tubercle, it is at the same time clear that the victims of the hereditary taint are only here and there, perhaps one out of a large family, or one member of a family in childhood and another in the second half of life, according as they had been exposed to sufficient exciting causes. In the most extreme cases of heredity, which are not so rare but that one or more are familiar to every circle, the members of a family fall into consumption one after another as they grow up, as if by an inevitable fate. The relation of scrofula to tubercle is a subject of much intricacy. The familiar instances of scrofula are the enlarged clusters of lymph atic glands of the neck in boys and girls, who are either of the fair and delicate type or of the dark and coarse type. Another large class of scrofulous cases are subject to white swellings or other chronic diseases of joints, usually the knee, hip, or elbow. But many slighter conditions, such as eczema of the head and face in children, are set down to scrofula. Again, serious visceral disease leading to a fatal result, especially in the kidneys, testes, ovaries, and bladder, is for some reason reckoned scrofulous rather than tubercular. But this latter class of cases is certainly tubercular, as much as anything can be said to be tubercular. A great part of all that is reckoned scrofulous may be said to be inherited tubercle, affecting the lymphatic glands of the neck most conspicuously, running a very chronic course, often disappearing at puberty, and associated with a delicate skin, fair hair, large eyes, and other features of a well : known type. Of the cases of scrofulous disease in the genito-urinary system and in the joints there may be some in which the disease had been inherited, but there are others in which it had been acquired. The senile scrofula of workhouses and the like is almost certainly an acquired condition. Whether as an inherited disease or as an acquired, scrofula can be separated from tubercle by no very definite line. Tubercle, as the name implies, is a small tuber or round nodule; the nodules are often "miliary" or the size of millet-seed. For the variety of diffuse or " infiltrated " tubercle, which is often found in the lungs, it has been made a question whether it should be reckoned as tubercle at all, by reason of its wanting from first to last the character of distinct small nodules. Tubercles are some times large, especially the tubercles of the genito - urinary organs and of the brain ; and these are generally made up of a number of smaller nodules fused together, and surrounded by a common cap sule. The larger tubercular masses, or conglomerates of tubercles, are those that have been claimed as in a peculiar sense scrofulous. The fusion of numerous small tubercular centres into one large area can often be seen in lymphatic glands in all its stages under the microscope. The prevalent modern opinion is that all these vari ous manifestations are due to the infective action of a virus, just as in syphilis ; and, as the effects of the syphilitic virus include not only gummatous nodules but also " inflammations "of the skin, mucous membranes, periosteum, and other textures, so the effects of the tubercular virus include not only "tubercles," properly so called, but also a variety of diffuse " inflammatory " conditions. The most common seat of the tuberculous process is the lungs, so that tubercle and phthisis pulmonalis have almost come to be synonymous. In a certain proportion of cases the tubercles and tuberculous "infiltrations" are found in the lungs only; but in many cases the pulmonary tuberculosis is only a part of a general infection which includes the serous membranes and lymphatic glands, the intestine, the liver, the spleen, the kidneys, the brain- membranes, the choroid coat of the eye, the bones, and the joints. Cases have been described also of tuberculous ulcers of the tongue and stomach, and of tubercles in and around the thoracic duct. On the assumption that tubercle is due to an introduced virus, it has been attempted to classify the cases according to the probable way of ingress of the virus ; those with the pulmonary condition most prominent would have received the infection with the breath, while another class, including the numerous cases where miliary tubercles are found in the liver when carefully looked for with the microscope, would have absorbed the virus along with the food from one part or another of the digestive mucous membrane ; the tuberculous kidney (with ureters and bladder), again, would be explained on the hypothesis of that organ attempting to eliminate the virus from the system. But even among the pulmonary cases there are some in which the tubercles had arisen from infection brought by the venous blood, just as in the dissemination of sarco- matous tumours ; it has been shown by the very elaborate dissec tions of Weigert that tubercles may grow into the walls of veins, the tuberculous substance so getting carried into the blood-current, wherein the first resting-place would be the pulmonary capillaries, except when the vein was tributary to the portal system. It is difficult to say what is the most characteristic structure of a tubercle. In the class of small grey translucent tubercles, all the same (miliary) size, the cells are practically granulation-cells ; these are not uncommon in childhood and youth, where the attack is sudden and the progress ra nd. In another kind, which Kind-