Lymphoid tissue Diseases

In the human body there are several organs or masses composed of lym­phoid tissue. This tissue is largely formed from special cells of small size called lymphocytes. They are identical with certain cells which normally make up about a third of the total number of white blood cells; and it is evident that lymphoid tissue is the origin of this class of blood cells.

Some of the lymph­oid organs are the spleen, a large solid structure in the upper left side of the abdominal cavity; the thyyntis, in the chest cavity, just behind the upper part of the breastbone; and the lymph nodes, of which there are five or six hundred scattered in different parts of the body. These latter vary in size but are all small, most not larger than a small bean. There are many in the sides of the neck, the armpits, the groin, the central part of the chest cav­ity, and the abdominal cavity.

Other important collections of lymph­oid tissue are the Peyer's patches in the lower part of the small intestine; the tonsils, situated on the sidewalls of the throat near the back part of the tongue; the adenoids, also called the pharyn­geal tonsils, on the upper part of the rear wall of the throat; and the appen­dix, attached to the large intestine near the place where the small intestine joins it.

Any of these structures or collections of lymphoid tissue, except the Peyer's patches, can be removed with­out causing any apparent harm to the body, though while they are in it and in normal health they serve very im­portant purposes. Most of them act as obstructions to foreign particles, dis­ease germs, and even chemical poisons, in their passage toward the blood­stream. All the channels or vessels that carry the lymph from the various parts of the body toward the large veins in the chest pass through lymph nodes on the way. The nodes act as sieves to catch and sift out harmful objects or materials. The importance of this ac­tivity of lymphoid tissue should not be disregarded when removal of tonsils or adenoids is being considered.

Diseases associated with the thymus, also inflammations of the tonsils, ade­noids, and appendix, are discussed else­where in this volume. Inflammation of the Peyer's patches occurs almost solely as a feature of typhoid fever. The spleen is involved in several different diseases, but it is seldom if ever the seat of a disease by itself. Virtually every infection or infectious disease that attacks the human body involves the lymph nodes but usually only sec­ondarily. In this chapter we shall con­sider in detail only Hodgkin's disease, in which the lymph nodes are primar­ily affected, and swelling of the lymph nodes, which occurs almost every time they are involved in any other dis­ease. It is important to know that this involvement sooner or later always oc­curs with cancers as well as with in­fections by disease germs or viruses.

HODGKIN'S DISEASE.
Hodgkin's disease is a chronic, pro­gressive, usually fatal disease which has a higher incidence among men and boys than among women and girls. Typically it begins in young adulthood. Its cause is not yet surely known. Its onset is gradual. The lymph nodes en­large progressively. Those located where they can be felt are firm and elastic to the touch, but they remain freely movable and do not mat to­gether. Troublesome itching is likely to develop early, and there may be ex­cessive sweating. Later the victim has spells of moderate fever, is weak, loses weight, and becomes pale and anemic. The symptoms and signs of this dis­ease, however, are so nearly like those of some other diseases that about the only sure way to detect its presence is for a physician to arrange for the re­moval and microscopic examination of one of the enlarged lymph nodes.

There are many possible distressing developments in the course of Hodg­kin's disease. While the lymph nodes in the neck are usually the first to be af­fected, and while the swollen nodes are not painful, those in the interior of the body often press upon various organs and structures and interfere with their functions. The physician in charge of the case will usually be able to judge from the symptoms where the enlarged nodes are, how great the need of an­tineoplastic drugs and X-ray treat­ments is, and whether or not some other treatment should be tried. Suit­able dietary and nursing measures may help to maintain the victim's strength and add to his comfort. No matter how treated, however, Hodgkin's disease is usually fatal, its course typically run­ning not more than five years; but with the best treatment life is made more endurable or even comfortable, and sometimes prolonged for as much as twenty years. Mild cases in which the involvement is limited to a single area, when treated early, may remain symp­tom-free for many years, during which time life and its activities may be ap­parently normal.

What to Do
1. If Hodgkin's disease is sus­pected, place the victim under a physician's supervision immediately. He will first do what is necessary to determine whether or not the disease is actually present; and, if so, he can begin at once to give the most effec­tive treatment.
2. The victim should be encour­aged to follow a program that will build up his general health. He should never be made to feel that all he can do is to lie down and wait for death.

SWELLING OF THE LYMPH NODES.
Nearly all the disease conditions af­fecting the lymph nodes produce an enlargement which can easily be seen and felt if the affected nodes are situ­ated near the body surface. These swellings are more likely to be painful and tender if they are caused by in­flammation or if they develop rapidly.

A sore throat, a sore mouth, a bad cold, infected tonsils, or disease of the middle ear is usually accompanied by swollen and tender lymph nodes on the sides of the neck and underneath the jaws. An infected hand or a sore on a hand or an arm is likely to be accom­panied by swelling of the nodes in the corresponding armpit. Sores on the scalp often lead to swollen nodes be­hind the ears and on the back of the neck. Infections of the feet or legs fre­quently cause swelling of the nodes in the groin. These swellings usually sub­side with the disappearance of the con­ditions which occasioned them, but meanwhile some of them may require medical or surgical treatment on their own account.

In various acute infectious diseases, including scarlet fever, smallpox, and typhoid fever, many of the lymph nodes throughout the body are in­flamed and swollen. Bubonic plague gets its common name from the fact that, in most cases, the lymph nodes throughout the body, but often most noticeably those in the groin, are in­flamed, and pus forms in them. Such inflamed lymph nodes are called bu­boes. Uninformed or ignorant people sometimes call them "blue balls."

There is a peculiar disease known as glandular fever or infectious mononu­cleosis, in which many of the lymph nodes throughout the body, but espe­cially those in the neck, may be swol­len and tender. This disease may last from a few days to three or four weeks, but is seldom a menace to life. It is probably caused by a virus. It is char­acterized by fever, sore throat, and general weakness in addition to the swollen lymph nodes; and the spleen is often enlarged and the liver often in­flamed.

Occasionally there is a skin rash. The most distinctive sign, how­ever, is the presence in the blood of a special form of white blood cell, called a mononuclear, which, of course, can­not be detected without an examina­tion of the blood. In the most severe cases, weakness may persist for two or three months after all other symptoms have subsided.

Tuberculosis frequently involves the lymph nodes of the body. In most cases of tuberculosis in which the nodes seem to be affected more than any other tissues, children are the victims; and the nodes eventually heal, but with calcium deposits in many of them, es­pecially those in the chest. Tubercu­lous nodes may break down and form pus, however. Lancing such a node is not likely to do much good, but some­times it is advisable to remove the en­tire node. In many such cases, the cat­tle tubercle bacillus is the cause of the infection, the child having been in­fected by drinking raw milk or eating raw milk products coming from tuber­culous cows.

Syphilis always involves the lymph nodes. Accompanying the primary sore on the genitals, there is painless swell­ing of the nodes in the groin. Later, in the second stage of the disease, the nodes throughout the body become hard and feel as if they were enlarged; but they neither become painful nor have pus in them.

As mentioned earlier in this chapter, there is an important connection be­tween cancer and the lymph nodes. Enlargement of the nodes because of cancer is different from that from many other causes. It comes from the trans­ference of cancer cells to the nodes from the original sites and the devel­opment of cancer in the nodes them­selves.

An outstanding example of this process occurs in the armpits, cells be­ing carried there from cancer in the breast. Other nodes frequently in­volved are those under the jaws and on the neck, to which cells are carried from cancer of the lips, mouth, or tongue. In the treatment of cancer anywhere it is as important to detect any lymph nodes that may be involved and to remove them as it is to detect and remove the original tumor. Other­wise no real cure is possible, and im­provement is only temporary.

What to Do
1. Try to learn the cause of the swelling, securing the aid of a physi­cian if needed.
2. If the swollen lymph nodes are painful and tender, and if they are located in an accessible place near the body surface, apply hot fomenta­tions over them three times a day.
3. Keep the patient under a physi­cian's care, if possible, so that any pus formation may be promptly de­tected, and the node or nodes may be lanced and drained without delay if such treatment should be needed.