SPLEEN, DISEASES OF.—The spleen shows little tendency to primary disease, but is easily affected secondarily in in fectious states of the blood and in dis eases of the blood-forming organs.
Excluding enlargements of the spleen due to malaria, syphilis, leukmmia, rachitis, etc., the primary enlargements of the spleen are divided into two classes: 1. Those that give rise to no symptoms except of a mechanical nature. These are more common than is gener ally supposed. 2. Those that are asso ciated with amemia, for which the term splenic anminia is to be preferred. The special features of these are their chronic course: the bronzed skin, the chlorotie type of blood, and the limmorrhages. William Osler (Phila. Med. Jour., Dec. 17, '95).
The splenic substance consists essen tially of an aggregation of lymphoid tissue with a very rich vascular supply. Its function is uncertain, but that it is not essential to life or development is shown by the effects of its removal in lower animals as well as in man. If it has become materially altered by chronic disease its removal is not followed by any definite disturbances other than those incident to the operation, as compensa tion has often previously been estab lished.
After the removal of a healthy spleen, however, there are marked constitutional disturbances. The following symptoms have been noted: Extreme amemia, emaciation, daily rise of temperature and increased frequency of pulse, attacks of fainting, headache, drowsiness, great thirst, severe griping pains in the ab domen and pains in the arms and legs; marked enlargement of the lymphatic glands, which may be permanent and compensate for the loss of the spleen; great diminution of the red blood-cor puscles, and considerable increase of the leucocytes.
The spleen personally extirpated in some 200 guinea-pigs. and subsequently virulent diphtheria bacilli or the toxins obtained from them have been injected. With the toxins there was no distinct difference between the animals with or without their spleens. In the case of the bacilli, animals deprived of their spleen lived longer than the others. With the injection of virulent anthrax the animals died in about the same time, whether the spleen had been previously extirpated or not; ony one animal, and that with out its spleen, survived. Different re
sults were obtained with a virulent pyo cyaneus toxin and an active cholera culture. In the case of the bacteria the animals without their spleen lived much longer than the others. Thus, both with diphtheria, cholera, and proeyaneus ba cilli the animals deprived of their spleen showed increased resistance, and espe cially with the two last-named bacilli.
A considerable leucocytosis followed upon the splenectomy. Thus it is con cluded that the splenectomy produced the hyperleucocytosis, and this latter led to an increased bactericidal action of the blood and to an increased re sistance against infection. Blumreich and Jacoby (Berl. klin. Woch., May 24, '97).
After splenectomy the red blood-cells and hseznoglobin are greatly diminished, and the leucocytes increased, and shortly after operation (ten to twenty-three days) the red blood-cells and leucocytes are again normal in ratio. There is, however, a deficiency in the amount of haemoglobin which persists, in slight de gree, for some months. Frank Hartley (Med. News, Apr. 2, 'M.
The symptoms gradually abate; con valescence is slow, but recovery becomes complete. In children these symptoms are much less marked and may be absent, probably on account of the great abun dance of lymphatic tissue and of red bone-marrow in early life. In some cases the existence of accessory spleens doubt less accounts for the absence of symptoms after removal.
Hyperaemia of the Spleen. — Acute hyperaemia of the spleen occurs fairly constantly in acute infectious diseases, such as typhoid fever, septimmia, and ulcerative endocarditis. It is also met with, but less frequently and in less marked degree. in toxaemia. In all in fectious diseases there is great tendency to the accumulation of bacteria in the spleen. The free blood-supply sweeps them into the spleen and on account of the slower current through its dilated vessels they are left behind in its sub stance where they may be found, in many instances, weeks after they have disappeared from other organs.