There are certain pathological and even physiological conditions during or after which an inflammatory affection of one or several joints closely resembling acute articular rheumatism more or less frequently arises. Thus, during the early desquamating stage of scarlatina a mild inflammation of the joints of the hands and feet, and frequently of the large articulations as well, is very often seen, and it is attended with profuse perspiration, with a condition of urine like that of ordinary acute rheumatism, and occasionally with inflammation of the heart or pleura. During convalescence from dysentery an affection of a single or of several articulations resembling rheumatism has been noticed, and the two affections have even alternated in the same patient. That singular epidemic disease dengue is attended with a polyarticular affection closely resembling acute articular rheumatism, occasionally pursuing a protracted course, and not seldom leaving after it a cardiac lesion. In hæmophilia polyarticular and muscular disorders frequently arise which closely resemble, and appear to be sometimes identical with, ordinary acute articular and muscular rheumatism. Gonorrhoea too is often associated with a febrile polyarthritis, and rarely with an endocarditis at the same time. In the puerperal state an inflammation of one or several articulations is not unfrequently observed (puerperal rheumatism). Respecting the real nature of these polyarticular inflammations very much has to be made out; and it must suffice at present to say that while many of them are of a pyæmic nature, as some examples of puerperal and scarlatinal arthritis, in which pus forms in or about the joints and in the serous cavities and viscera, some of them are no doubt examples of genuine rheumatism occurring in persons of rheumatic predisposition, which have either been induced by the lowering influence of the disease upon which they have supervened, or by the accidental coincidence of some of the other causes of acute rheumatism. There remains, however, the ordinary form of scarlatinal arthritis, which so closely resembles true acute articular rheumatism in its symptoms, course, visceral complications, and morbid anatomy that it cannot be said that the two affections are distinct and different. And much the same appears to be true of the articular affection of dengue. Yet so frequently does the articular affection accompany scarlatina and dengue respectively that it cannot logically be referred to a coexisting rheumatic predisposition, and must be a consequence of the disturbing influences of the specific poison of those zymotic affections per se. PATHOLOGY.--The pathology of acute articular rheumatism is a very much debated question, and is not at all satisfactorily known. Hence a mere statement of the most prominent theories now held by different pathologists will be given.[12]