causes of lymphadenoma are obscure. Diathetic ten dencies have been supposed to give rise to the disease, and there is no doubt that in some cases pulmonary consumption or syphilis has been noted in the parents. In other cases, however, the family history has been good. Acute disease in the child himself has sometimes appeared to be the starting-point for a slow deterioration of health which has event ually developed into undoubted lymphadenoma. So also the occurrence of the illness has been attributed to bad or insufficient food or insanitary conditions generally. In some cases, however, no sufficient cause has been discovered to account for the failure of health. The disease, like tuberculosis, with which it presents certain affinities, may develop without apparent reason in a child whose health had previously given no cause for anxiety.
In not a few cases some local derangement or injury has appeared to be the exciting cause of the enlargement of the lymphatic glands. Thus a decayed tooth, a patch of eczema, an otorrhcea—all these have been known to be quickly followed by a swelling of the glands in the neighbour hood of the irritant. In scrofulous subjects a persistent caseous enlarge ment of glands from this cause is not uncommon. In lymphadenoma, however, the morbid changes do not remain limited to the neighbourhood of the irritant. Others more distant from the seat of irritation take on the same unhealthy action, and thus the disease spreads widely so as to involve adenoid tissue in all parts of the body.
The age of the children affected is usually four or five years and upwards. I have, however, seen a well-marked case in an infant eight months old, who had begun to suffer at the age of three and a half months.
Morbid Anatomy.—After death in a case of lymphadenoma we usually find, great enlargement of the lymphatic glands, and often of the spleen, the liver, and the kidneys. In addition there is commonly overgrowth of the more minute collections of adenoid tissue in various parts of the body, as in the tonsils, the pharynx, the gullet, the stomach and intestines, etc. Of these the more considerable enlargements are often limited to a com paratively few organs and structures, but microscopical examination dis covers very wide-spread changes in parts which present little or no apparent alteration to the unassisted sight.
The lymphatic glands are greatly enlarged, and the enlargement may be in two forms—a hard and a soft swelling. This difference appears to depend less upon the nature of the growth than upon the rapidity of its progress, for the two varieties tpay be found combined in the same subject.
The size of the swollen glands commonly varies from a hazel-nut to a hen's egg, but in exceptional cases the growth may reach still more con siderable dimensions. The first glands to be affected are usually those in the neck. Then follow in order of frequency the axillary, inguinal, retro peritoneal, bronchial, mediastinal, and mesenteric. But besides enlarge ment of glands, circumscribed growths may be developed in spots where, although adenoid tissue exists normally in small quantity, it is not col lected into glandular masses. By this means the various groups of enlarged glands may be found connected together by chains of newly developed. lymphatic nodules.
When a group of glands takes on the morbid process, the individual bodies at first remain distinct and are movable. As the disease progresses they cease to be movable, and eventually become welded together into a solid mass. The process of union consists in a disappearance of the cap sule, which becomes pierced and ultimately almost destroyed as the new lymphatic tissue accumulates. On examining such a mass the outline of diseased glands can be recognized here and there by a thin fibrous capsule, but the confluence is for the most part complete, and no intervening infil tration can be discovered. On the surface the mass is often very irregular and nodulated, and may be mottled with white or yellow patches, but caseation is seldom seen. If the mass be superficial it may be adherent to the skin. In rare cases it suppurates. The greater or less hardness of the enlarged gland is determined, as has been already said, by its rapidity of development. If it grows very quickly the gland is soft. On section of such a gland the substance appears often to be almost diffluent. If firmer, it yields a creamy juice when scraped. If very firm the hardness is found to be due to hyperplasia of the fibrous stroma, dense bands of fibrous tis sue running in various directions through the mass.
Under the microscope the morbid change in the glands is seen to con sist in an enormous increase in the lymph corpuscles. These accumulate, and by their pressure may perforate the capsule and even split up the septa and cause them to disappear. In the softer growths the diseased process is chiefly of this kind. In the firmer glands there is an increase in the fibrous stroma, which becomes greatly thickened. The hypertrophy may even obliterate the meshes of the reticulum and convert the organ into a mass of fibrous tissue.