The presence of bacteria in the spleen causes hyperaemia and swelling of the organ, especially marked in early life, when the lymphoid tissue is most abun dant and the capsule most distensible. The swollen spleen is usually soft, may be even diffluent; but it may be firm, especially in more chronic cases, or in repeated attacks. The substance is usu ally dark, but it may present a grayish color from the great number of leuco Bytes present. The Malpighian bodies are generally affected, being swollen on account of great proliferation of their cellular elements, which may show ne crotic changes caused by the toxins.
The pulp also shows much prolifera tion of its cellular constituents, and may present areas of necrosis, and many small hemorrhages. Similar changes may be caused by toxemia without the presence of bacteria in the spleen, but they are less marked, as the poison is much less concentrated than it is when produced in the spleen by active bacteria present.
Malformations. — The shape of the spleen may deviate greatly from the nor mal. It may be rounded or elongated. Its anterior margin may present several notches, or a single deep one almost di viding the spleen into two parts. The notch may be near the lower end or even on the posterior border. Long processes may be given off from the main body; such a process has been met with extend ing down into the serotina, doubtless carried there in the descent of the tes ticle. Accessory spleens—splenculi or lienculi—are quite often met with, usu ally in peritoneal folds near the hilum. Occasionally the spleen is represented by a number of small masses scattered about the peritoneum or clustered into masses like bunches of grapes. They may be come imbedded in the spleen itself. They arc supposed to be more common in early life. Congenital absence of the spleen is very rare in otherwise normal bodies.
Atrophy.—In children the spleen is large; after middle life it undergoes atrophy, as is the ease with other lym phatic structures, such as the tonsils, Peyer's patches, thymus gland, etc. In old age atrophy may be of extreme de gree, only a remnant being left. The capsule is shriveled and thrown into folds; it is somewhat opaque and thick ened. From atrophy of the pulp the ves sels and trabecule stand out promi nently. In some eases there is great in
crease of the interstitial connective tis sue as in cirrhosis of the liver or kidney, and the organ may not be reduced in bulk.
Hypertrophy.— SYMPTOMS.— There is usually marked anemia and often inter nal hemorrhages, especially intestinal; but these symptoms are probably due to the associated conditions rather than to the spleen itself, and to these the treat ment should be directed.
Cases of so-called primary enlargement of the spleen are divided into: (1) those in which the spleen is enlarged without causing any symptoms other than those clue to mechanical pressure: (2) cases of enlargement accompanying anaemia. The former condition is more common than is ordinarily suspected. Usually in this class the spleen is only moderately large. In the past few years there have been personally seen 4 patients, all women, apparently in perfect health, complaining only of a feeling of pressure in the abdomen, in all of whom the spleen was much enlarged. The term anaemia spleniea, which describes the second class, should be restricted to those cases in which progressive anae mia develops in connection with primi tive splenomegaly. The relation of the enlarged spleen to the anaemia is still in doubt. Four eases of this class have come to personal notice during the pres ent year. The peculiarities manifested in these cases were the remarkably chronic course, extending from 3 to 12 years, the chlorotic features of the blood, the hmmoglobin value often not more than 50 per cent.; the peculiar bronzing of the skin; and, lastly, haemorrhages, which may be toxic, as in leukaemia, and wide spread or mechanical, resulting directly from the condition of the enlarged spleen. Particular attention is called to the con dition of bleeding, in which for many years haemorrhages occur from the stom ach and bowels; the bleedings are pro fuse, and in the above cases they occurred during a period of from nine to twelve years, while in the intervals the patients have regained their flesh and strength and have been able to carry on their oc cupations. The special feature of Inemor rhages in these cases are considered en tirely due to mechanical causes. In no case have there been associated cutaneous or retinal haemorrhages.