It is evident that it will often be extremely difficult, and sometimes even impossible, to determine the extent to which symptoms are occasioned by the splenic congestion or by the general affection to which it owes its origin. Mosler declares that he is nearly always able to detect during the cold stage of intermittent fever a peculiar murmur over the splenic region and upward and downward in the abdominal region, which he attributes to the contraction of the splenic artery. This murmur he has not been able to perceive in chronic splenic tumors.2
2 Ziemssen's Cyclop., vol. viii. p. 468.
The normal splenic area can only be defined by percussion, and congestion to a not insignificant extent may occur without revealing itself by other symptoms than increase of the extent of percussion dulness. When the organ projects beyond the margin of the ribs and can be felt by the fingers of the examiner, it is enlarged, unless the patient is the subject of displaced or of wandering spleen. But whether the enlargement be due to hyperæmia simply or to hypertrophy can only be determined by a consideration of all the concomitant circumstances. Unless under the influence of chronic irritation or as a result of mechanical hyperæmia, congestions of the spleen are commonly of sudden development and of transitory duration. In ordinary inflammations, such as pleurisy, etc., the degree of congestion is so slight as to be unnoticeable; but as an epiphenomenon of the various specific fevers the enlargement occurs rapidly and acquires a prominent interest in many cases. Acute splenic tumor, for example, is almost of constant occurrence during the course of typhoid fever, and, according to Friedreich, its presence may be ascertained some days before the specific symptoms of the disease have declared themselves. A similar early development has been claimed for it in diphtheria and other affections. The congested spleen of typhoid fever and of relapsing fever, however, differs from that of most other acute disorders in returning to its normal dimensions much more slowly; and it is important to remember that until the splenic tumor has disappeared there is reason to believe the danger of relapse still imminent. In most cases the enlargement disappears pari passu with the disorder that occasioned it. In malarial fevers and in septic diseases the splenic tumor may acquire excessive dimensions. Acute splenic tumor, however, never attains the dimensions often encountered in chronic congestion and hypertrophy.
PATHOLOGY AND PATHOLOGICAL ANATOMY.—Simple splenic congestion presents at first no anatomical features differing from purely physiological hyperæmia. There is simply more blood in the dilated vessels and vascular spaces, and consequently in the viscus, than is usual. Very soon, however, there is hyperplasia of the cells of the pulp. Enlargement, tension of the capsule, and diminished consistency of the spleen appear. The color will depend upon the condition of the capsule, being most dark and blue when this is thinnest. In high grades of congestion the parenchyma upon section will be found distended and semi-diffluent, and after acute malarial fever (pernicious remittent fever), the organ may resemble a bag of half-liquid pulp. Softening in varying degree may be found after acute congestion from whatever cause. In the congestions due to some infective processes at least additional factors are introduced, although as yet definite knowledge of their exact pathogenetic influence has not been attained. The observations connecting minute organisms with the origin of these affections have been so elaborate, so carefully and conscientiously reported, extend over such wide and varied fields, that it is difficult to refuse to place reliance in them. It seems that in a number of affections the presence of these microscopic organisms is constant and essential, and that the splenic congestion that accompanies them is a direct result of their presence in the spleen itself. The micro-organisms will be found infesting the cells of the pulp, and, so far as we have definite knowledge, they show peculiar characteristics according to the particular infectious disease to which the patient succumbed. While the conditions in acute splenic tumor are identical with those of inflammation, and in the affections properly designated as septic, should the life of the patient have been sufficiently prolonged, may be found to have led to the formation of embolic centres with hemorrhagic infarctions and abscess, in infectious diseases not septic they do not prove equal to the production of suppuration. Where the action is acute, resolution will speedily follow the subsidence of the febrile process. But in prolonged hyperæmia new formation will be developed, and the enormous collection of leucocytes will give a reddish-gray color to the organ. This change will also be sometimes observed in the spleens of those in whom the infectious diseases have run a more protracted course.
DIAGNOSIS.—Acute splenic tumor, if at all pronounced, may usually be diagnosticated without much difficulty. The development of an enlargement in the splenic region, with pain and tenderness to pressure, during the course of any acute febrile disease will nearly always indicate splenic hyperæmia. It may sometimes be difficult to determine whether the tumor may not have existed prior to the invasion of the present malady. In such cases one must have recourse to the previous history of the patient, or, failing in this, must observe the behavior of the tumor upon the subsidence of the general affection.
PROGNOSIS.—The prognosis of acute congestion and acute splenic tumor will depend rather upon the exciting cause. When of simple origin it is of but insignificant importance. Even in specific fevers the spleen will in most instances return to its normal volume upon the establishment of convalescence. Rupture of the spleen has been known to occur in congestion from severe malarial fever, but this is a most rare accident in the absence of traumatic influences. The congestion may become chronic, and frequently does become so, in cases where the stimulus continues to exert an influence upon the spleen, as is done in chronic malarial poisoning.
TREATMENT.—The transitory hyperæmia of a brief malarial attack or of any ordinary febrile seizure will disappear with its exciting cause, and will require no special treatment. For the acute congestions of most specific fevers but little is to be done except through attention to the general condition: it is only when pain and discomfort in the splenic region are sufficient to attract the attention of the patient that measures for the relief of the congestion will be necessary. In that most common exciting cause of it, malarial fever, patients will often complain bitterly of the pain in the left hypochondrium for some time after the febrile attack has been overcome. In such cases it may be pretty safely concluded that the poisonous influence of the malaria has not been entirely overcome, and the proper employment of quinine and other derivatives of Peruvian bark, and bitter tonics, will undoubtedly prove most serviceable. In very many cases benefit may be derived from local applications. Experiment has clearly shown that the stimulation of the splenic nerves is capable of effecting a notable reduction in the bulk of the organ. Clinical experience gives similar proofs, and cold effusions, evaporating lotions, etc. will sometimes secure prompt unloading of the spleen; indeed, Mosler considers that there is danger in treating the acute splenic tumor of typhus fever of inducing unfavorable changes by the too sudden reduction of its bulk by local applications. The use of stimulating applications to the splenic region will also prove beneficial in many cases. Among the most valuable of these will be found the tincture of iodine.
Chronic Congestion and Enlargement of the Spleen.
Within narrow limits there may be simple increase in the size of the spleen from hyperæmia, without alteration of the relations between its structural parts. The common results, however, of hyperæmia of long standing are overgrowth of the elements of the reticulum, with new formation of connective tissue and hyperplasia of the pulp-tissue. This condition of chronic enlargement or hypertrophy of the spleen may develop as a result of chronic active hyperæmia or through passive or mechanical engorgement of the portal system. Chronic active hyperæmia of the spleen is in much the greater number of instances caused by chronic malarial poisoning. It also occurs as a cause or a result of leucocythæmia and of pseudo-leucocythæmia or Hodgkin's disease, and is always associated with more or less true hypertrophy of the structural elements of the organ. Enlargement from the above-mentioned causes constitutes the vast majority of those abnormalities generally designated as chronic splenic tumor. In persons living in malarious countries, and subjected for prolonged periods to the intoxicating influence, the peculiar splenic enlargement tends to become chronic. After the earlier attacks the spleen returns more or less promptly to its normal dimensions. Usually it is only after repeated attacks of intermittent or remittent fevers, and often only after exposure to the malarious influence for years, that the splenic tumor becomes established as a permanent disorder and assumes the characteristics that have secured for it the popular denomination ague-cake. Persons living in the localities referred to may develop this enlargement without ever having had unequivocal attacks of malarial fever. They will betray, however, the effects of the poisoning by malarial neuralgias and neuroses or by a well-marked periodicity in the course of simple maladies, or they will exhibit its effects by the peculiar facies and by general paludal cachexia. Under these conditions the splenic enlargement sometimes attains enormous proportions.
Splenic enlargement of considerable extent may result from mechanical hyperæmia of the portal circulation from cirrhosis of the liver. It is, however, certainly not a necessary consequence of cirrhosis, since this may exist to a pronounced degree and yet the spleen remain normal—a condition that is probably favored by extensive distribution of muscular and elastic fibres to the viscus, that enable it to a great extent to regulate its own circulation. On the other hand, the spleen may be atrophied by a fibrotic contraction of its trabeculæ, the result of long-standing hyperplasia. Chronic engorgement and enlargement of the spleen may also result from mechanical obstruction to the systemic venous circulation, especially that due to insufficiency of the mitral valve, whereby obstruction to the portal circulation arises secondarily. (The ulcerative endocarditis of septic origin is associated with splenic congestion, which is, however, always of the acute active variety, and complicated for the most part with embolic abscess and hemorrhagic infarction.)