LYMPHADENOMA. HODGKIN’S DISEASE.
Definition. Relation to leukæmia. Causes. Mainly accessory. State of lymph glands, spleen, liver, bone marrow, intestine, tonsils, thymus, kidneys, liver, lungs, bronchial mucosa, pleura, pericardium, nervous system. Symptoms, as in leukæmia, with adenoid hyperplasia, but little leucocythemia. Relation to glanders. Uric acid, low density, no hippuric acid. Tuberculin and mallein tests. Treatment, as in leukæmia. Excision in cases not constitutional. Phosphorus, phosphide of zinc.
Definition. Hypertrophy of the lymphatic glands with little or no leucocytosis. There may further be lymphoid growths in the liver, spleen, bone marrow and other organs.
The visceral lesions in lymphadenoma do not differ in character from those of leukæmia, and as it does often apparently merge into that disease by the characteristic changes in the blood, it is denied by many that it constitutes a separate pathological entity. In his admirable monograph on leucæmia in the lower animals Nocard affirms their identity. The main excuse for keeping up an alleged distinction, is the frequent absence of leucocytosis, and this often supervenes after the lymphadenoma has existed for some time.
Causes. As in leucæmia, no definite cause can be found in the majority of cases. An accessory cause can sometimes be observed where a local irritation gives rise to swelling of the adjacent lymphatic glands and this goes on to distinct lymphadenoma.
Lesions in the Lymph Glands. The hyperplasia may affect but a single group of glands, more commonly a number of groups, and often nearly all. In one case only of leukæmia in the lower animals, a dog, has Nocard failed to find the lymph glands affected. In the horse he has found the sublumbar glands alone weighing 14.5 kilogrammes, 11 k. and 8 k. They compressed the posterior aorta and vena cava and had caused extensive ascites.
The enlarged glands are white, gray or in case of rapid growth veined or pointed with red; they may be soft or firm according as the hyperplasia has operated most on the trabeculæ or the cells; they are homogeneous throughout. The scraping of the cut surface gives a more or less thick milky juice containing a great number of nucleated or double nucleated lymphocytes, free nuclei and granules which stain strongly.
Hardened sections show an enormous development of the follicles at the expense of the medullary walls, and double nucleated white globules packed in a rich reticulum of adenoid tissue, whilst the bloodvessels in the connective tissue are crowded with white cells, and there are slight ruptures, old or recent.
Lesions of the Spleen. These are nearly always present. Leisering found a horse’s spleen over three feet long and 28 lbs. weight, and Nocard one of 13 lbs. Bollinger found a pig’s spleen 3½ lbs. Siedamgrotzky found dog’s spleens over 2 lbs. The consistency is usually firm (sometimes soft in dog). Capsule thickened and white, cut surface dry, reddish brown, granular, Malpighian bodies enlarged like a pea, hazel nut or walnut, with contents as in the lymph follicles. The capillaries are enlarged and crowded with white cells.
Lesions in the Liver. The liver is enlarged in one-half of the cases of leukæmia in the lower animals. It has been found to weigh 20 lbs. in the horse, and 4 lbs. in the dog. It is of a grayish brown, or yellowish brown hue, or light red spotted with yellow, or mapped out by anastomosing grayish white lines. There may be enlargement of the acini, or the formation of little nodes of adenoid tissue, or most commonly in the lower animals, there is an adenoid thickening of the bands of connective tissue extending in from the capsule. These are filled with white cells which stain deeply with carmine. There may also be slight extravasations of blood and infarcts.
Lesions in the Bone Marrow. These noticed in the pig by Fürstenberg, and in dogs by Siedamgrotzky, consist in increased vascularity, great cell hyperplasia, and formation of adenoid tissue as described under leukæmia.
Lesions of the Intestine. These commence in the agminated or solitary glands, which become enlarged, causing thickening of the mucous membrane, and later grow out into more or less rounded masses of lymph—adenoid tissue up to an inch in thickness. They are quite subject to ulcerations.
Lesions of the Tonsils. Bollinger, Nocard and Siedamgrotzky found these enlarged in dogs in connection with adenoma of the spleen. They were soft, friable, grayish, and consisted of a very delicate and fragile adenoid tissue.
In one case Siedamgrotzky found adenoid hypertrophy of the thymus in a cow, and adenoma of the kidneys similar to that of the liver has been noticed.
Similar adenoid hyperplasia has been found in the lungs, the bronchial mucous membrane, the pleura, the mediastinal and bronchial glands, and the pericardium. In man this has invaded the nerve centres, and it seems that at any point where there is a lymph gland or a lymph plexus this adenoid hyperplasia may localize itself.
Symptoms. The general symptoms of failing health are as described in leukæmia. The particular symptoms of this disease consist in the recognition of the adenoid hyperplasia in the absence of a marked leucocytosis. The submaxillary glands are usually the first attacked, and the disease may, in the horse, be confounded with glanders. There is, however, no pituitary discharge nor ulcer, the glands are enlarged symmetrically on the two sides, and a careful search will usually discover other groups with similar symmetrical enlargement. The parotidean, the pharyngeal, the prepectoral, the prescapular, the axillary, the popliteal, the prefemoral, the post and premammary, and the inguinal should be critically examined. The enlarged mesenteric glands may be reached and detected by the hand engaged in the rectum, or in the small animals by external palpation, as may also the enlarged spleen or liver.
The adenoid hyperplasia in the chest offers very obscure and uncertain symptoms. The enlarged bronchial and mediastinal glands may seriously interfere with the functions of the vagus nerve, causing, in cattle, disturbed digestion and rumination and tympanies, in horses stertorous breathing, and in the carnivora and omnivora a tendency to vomiting. In animals generally the pressure on the cardiac nerves leads to great irritability of the heart, and violent action under any exertion. The prominent dyspnœa in the advanced stages may be explained by these thoracic hyperplasiæ.
Nocard claims that the urine furnishes most important indications in its low specific gravity (horse 1010), its constant acidity, and in the almost entire absence in that of the horse of hippuric acid. When there is any suspicion of tuberculosis or glanders, the tuberculin or mallein test will decide.
Treatment is essentially the same as in leukæmia, and equally unsatisfactory. Arsenic has in the main given the best results. In the very earliest stages when the granular hyperplasia is confined to one group, excision is advisable. This should be avoided in all cases in which the constitutional symptoms have developed. Phosphorus and phosphide of zinc have seemed beneficial in certain hands. Injections into the glands have so far proved useless.