The development of the disease is generally subacute, occupying from one to several weeks. Fortunately the severe forms which we have just described are by no means frequent. In most of the cases the dis ease does not progress beyond a mild grade of muscular unrest, and then remains stationary for weeks or even months.
When the course is afebrile, the general health of the ehild is often remarkably little affected, particularly if the child is able to take suffi cient food, sleeps soundly at night, and sleep is not disturbed by muscular unrest. In children who are naturally delicate or markedly neuropathic. anorexia often develops early, along with the psychic depression, and may render the condition alarming. Severe cases are complicated by insomnia because the movements prevent the ehild from failing into a deep sleep.
The duration of the entire disease, up to the complete disappear anee of muscular unrest, may be said to be from one and a half to two months as a minimum, and from six to eight months as a maximum. A longer duration, say from one to two years, while possible, should awaken a suspicion that the illness is not a true chorea minor, but a symptomatic f orm.
Relapses are quite frequent in chorea. One or two may be ob served in the same individual, and it appears to make no difference whether the first attack is mild. or severe. As a rule relapses are milder and of shorter duration than the primary attack, but with each relapse there is increasing danger of the development of an endocarditis. It is to lye noted, however, that some at least of the eases of apparently secondary attacks axe not genuine chorea, and represent hysterical autoimitation. Even the most careful study of the clinical picture may not. enable the observer to distinguish between the two conditions, a positive decision being arrived at only by noting the prompt effect of suggestive treatment.
The relations of chorea to rheumatism and diseases of the heart are exceedingly important. Since the middle of the nineteenth century this subject has aroused the interest of numerous investigators, but their labors have failed to bring about any unity of opinion or to clear up the question entirely. It may be stated that it is now generally recognized that, in a large pereentage of cases of chorea the heart becomes involved in the course of the disease. The cardiac complication may be confined to the prcsenee of a slight blowing or breathing systolic mut. lanir, heard specially at the apex; quite frequently-, however, the accen tuation of the second pulmonary- sound and the persistence of the cardiac murmur after the chorea has run its course point to the existence of organic endocarditic disease. In harmony with these findings in the
moderately severe eases, we find almost without exception in the autop sies of sey-ere cases small excrescences of a granular nature, barely large enough to be visible and affecting especially the mitral valve, which prove that there was organic disease of the endoearilium. The vegetations are so small, howitA-er, that they produce no disturbances in the mechanism of the circulation and as a rule do not give rise to auscultatory- phenomena, or at. the most. to very slight physical signs in the heart. When we remember also that occasionally' the endocardium is found at. the autopsy to be perfectly normal even in cases in which there was a heart murmur during life, we shall be forced, with Wollen berg, to adopt the stand that statistics in regard to the frequency of heart murmurs and eardiae lesions in ehorea are of very lit.tle value, unless the patients are followed up, as has been done Lty Osier, Heinrich Meyer and others. When this is done, it, is found that about half of all choreic patients ultimately present positive clinical signs of chronic valvular disease.
Tn view of this close relation between chorea and organic disease of the heart, whieh is by no means clear to our understanding, the rela t.ion existing between chorea and rheumatism lyas for a long time been made the subject of investigation. Since we know that chorea ehiefly occurs during childhood and rheumatism preferably affects individuals who hay-e passed the age of puberty, it seems desirable to investigate, on the onc hand, how many choreic patients present symptoms of rheumatism either before or during their attack of chorea; and, on the other hand, to determine how many choreic patients are attacked by rheumatism when they attain adolescence. When this is done, it is found that the percentage of these cases is also very high, much too high to be explained by mere coincidence. In view of this fact one is forced to adopt the ViCW which H. Meyer, Heubner and others have taken, that the vague "rheumatic" joint pains, accompanied by depres sion and a general feeling of malaise, which not infrequently make their appearance before or during the choreic attack must be regarded as manifestations of the rheuniatie infection.