In diagnosing conditions associated with enlargement of the spleen it is necessary to recognize a primitive spleno megaly with a practically normal blood count. Cases of chronic enlargement of the spleen extending over many years present, as a rule, amemia of a chlorotic type, with ]ow corpuscular and leu cocyte count. The more pronounced does the corpuscular anmmia become, the more striking are the changes in the red corpuscles, and in advanced cases the blood may be like that of a pernicious anemia. The most confusing and puz zling condition, however, is that in which, with enlargement of the spleen, the condition of leukaemia may be pres ent during one month, and in the follow ing that of a simple splenic anaemia. The question of diagnosis from Banti's dis ease, primitive splenomegaly, with an as sociated terminal cirrhosis of the liver and jaundice, must be considered. Osler (Edinburgh Med. Jour., May, '99).
ETIOLOGY.—Great enlargement of the spleen is met with in chronic malaria, splenic anmmia, leukfemia, and occasion ally in cases in which no apparent cause existed. In rickets it is also said to be enlarged; but probably this is rather ap parent than real, and due to displace. ments of the spleen downward by de formity of the chest. The enlargement may be due to general and fairly equable increase of the various constituents of the organ, but in chronic cases the con nective tissue is usually in excess. The increase in size may be so great as to ex tend to the pubes below and well across into the right side of the abdomen, and it may weigh fifteen or twenty pounds.
Analyses of 304 eases of rupture of the spleen collected from the reports of over 9000 post-mortem records in India. Of the 304 cases, 147 were males and 157 females. Nearly half the number were from 25 to 45 years old. The youngest child was a female of 1S months, killed by a kick. As to the cause of the in jury, 102 cases resulted from blows with a club; 62 from blows with the fist, kicks, or slaps; 22 resulted from falls; while in 77 cases the person was run over. In 133 instances the rupture was on the inner surface, in 55 on the outer surface, and in 24 both surfaces were in volved. In 225 cases the rupture was single, and in 79 multiple. In 107 in stances the spleen was "much enlarged," in 125 "enlarged," in S there was no en largement, while in 64 no information on this point was given. In out of the 304 cases oine other organ suffered rupture in addition to the spleen, of which the most common was the liver in 75 instances and then the left kidney 5 times. D. G. Crawford (Indian Med. Gazette, June, 1902).
That the enlargement is not due to congestion alone is proved by the fact that it is never materially enlarged in diseases of the liver, heart, or lungs, in all of which venous obstruction is a prominent symptom. Some toxin or irri
tant seems necessary to produce the changes present.
—In malaria, quinine is indicated and in splenic arsenic is the only remedy that seems of service. In a typical case under my care a few years ago the use of arsenic succeeded satisfactorily, while general treatment with iron, etc., was of no benefit.
A comparison of the operations on the spleen may be thus stated:— (a) Removal of the whole spleen ne cessitates the ligaturing of: 1. The splenic branches or, what is the same thing in effect, the splenie artery and nerves before they divide into their ter minal branches. 2. The vasa brevia arising from the terminal or splenic branches. 3. The branches from the left gastro-epiploie and phrenic when present.
(b) Removal of the upper half necessi tates the ligaturing of the same arteries except the lower two or three terminal branches, as many as from twelve to eighteen vessels and nerves being in cluded in the ligatures on the pediele.
(C) Removal of the lower half can be effected by ligaturing the lower two or three terminal branches only. In the two latter operations there is, in addi tion, the continuous ligature across the spleen.
From this it will be seen that excision of either the whole or the upper half of the spleen involves great damage to the splenie plexus with its intimate (three fold) connection with the solar plexus and right vague; entails direct inter ference with part of the nerve-supply of the stomach and omentum, and severe indirect interference with the vagi and all the sympathetic nerve-supply of the abdomen; the diaphragmatic plexus is often involved and considerable tension has to be applied to the pedicle, and therefore on the coeliac and solar plexus and the vagi, thus augmenting the in terference with these nerves. The ex cision of the lower half entails but slight damage to the splenic plexus, and therefore but slight indirect in terference with the solar plexus and vagi; the nerve-supply to the stom ach, the omentum, and the diaphrag matic plexus is never involved and but slight tension has to be applied to the pedicle. As shock is due to severe inhibition and exhaustion of nerve-func tion, and, the grosser the lesion, the greater is the shock that results, this great difference in the amount of inter ference with the nervous system in these operations is the explanation of the great difference in the amount of shock fol lowing them: and in the excision of the whole spleen or of the upper half the resultant shock is due to inhibition and exhaustion of the vasoconstrictor fibres of the abdominal sympathetic, and is probably intensified by great interference with the proper performance of the functions of the heart, lungs, stomach, etc., reflexly by means of the vagi.