THE NATURE OF RHEUMATISM.
The nature of the change which takes place as the result of the action of the rheumatic poison has been the matter of some difference of opinion. The one point on which all are agreed is that it is inflam matory. The point on which opinions differ is as to the nature of the inflammation.
Rheumatic inflammation has been regarded by some as differing from ordinary inflammation, not essentially, but only in the pecu liarity of its seat. By others it is looked upon as specific in nature, as resulting from the action of a special poison which does not operate in the production of other than rheumatic inflammation. The former is the view taken by those who regard the disease as the direct result of exposure to cold and damp; the latter that held by those who look upon it as clue to the action of a special materies morbi circulating in the blood. That exposure to cold and clamp suffices to produce acute rheumatism is an old view which finds its chief support in the fact that the disease often occurs after such exposure. But so frequent is such exposure that it would be difficult to point out any disease which might not be attributed to this agency, if we are not careful to dis tinguish between the post and iwopter hoc.
If acute rheumatism owned such a causation, it ought to be most common iu the coldest climates, and during the coldest weather. But it is a disease of tempeinte climates, not of the arctic regions; aud, in temperate climates, is not always most common in winter.
It ought, too, if caused by cold, to be most common in children and in old people, who have little power of resisting cold; but the reverse is the fact; for the disease is most common at the age at which the power of resisting cold is greatest—from fifteen to fifty. If caused by exposure to cold, the joints which suffer most from such exposure, those of the fingers and toes, should also suffer most from rheumatism; but they are very rarely involved in the disease. Then again, if this be the cause of the disease, how is it that pericarditis so frequently occurs, and pleuritis and peritonitis so rarely? The pleura and peritoneum are just as much exposed to cold as the peri cardium, probably more so. And how, on this view, are we to ex
plain the occurrence of endocarditis, and the almost entire limitation of this to the left side of the heart? Again, it is an established fact in the history of acute rheumatism that fresh joints may be attacked after the sufferer has been confined to bed in a warm room for days and even weeks. These later joint attacks are identical in nature with the earlier ones which ushered in the seizure, and it would be unreasonable not to regard them as pro duced in the same way, and as due to the operation of the same cause. But it is quite impossible that they can be caused by expo sure to cold. The exclusion of cold as a possible cause in the case of these later joint seizures is a sufficient reason for calling in question its claims to be the cause of the earlier ones.
Other peculiarities of acute rheumatism there are which it is im possible to explain on this view of its etiology. The mere enumera tion of these will suffice to show that no amount of exposure is ade quate to their explanation.
The special characteristics of acute rheumatic inflammation are: 1. The tendency to its occurrence is hereditary—transmitted from father to son.
2. It is specially liable to occur at a particular age—being rare before fifteen or after fifty.
3. It is apt to attack the same individual again and again.
4. It does not confine itself to one joint, but affects several simul taneously or in succession.
5. It attacks also the membranes of the heart.
6. It very rarely terminates in suppuration.
7. It is not much benefited by measures calculated to relieve sim ple local inflammatory action, but is speedily subdued by proper con stitutional treatment.
There is no possibility of explaining these peculiarities by any view which does not recognize the existence and operation of a gen erally acting internal cause. No external agency can be regarded as adequate to the explanation of any one of them.