The natural history of rheumatic fever and rheumatic heart disease in the Orient.

Studies published in the past 10 years suggest that group A streptococcal infections are frequent in the Orient and lead to a high incidence of rheumatic fever (RF) and rheumatic heart disease (RHD). In the present study, streptococcal infections were found to be more prevalent in Japan and Taiwan, whereas RF and RHD were more common and severe in the Philippines, Thailand, and Indonesia, particularly among the socioeconomically less privileged populations. The pattern of childhood RF varied: Carditis was the most common manifestation, occurring in 57% to 94% of the patients; polyarthritis was generally atypical and less common in the tropics; chorea minor and erythema marginatum were much more common in Japan, less common in Taiwan and rare in the tropics. RF recurrences were quite common and led to the development of new carditis, and deterioration or persistence of the pre-existing heart disease. The 5 year mortality rates differed greatly, ranging from zero to 42%. There was disappearance of the heart murmur in 16.5% to 37.5% of patients. Such apparent recovery was related to adherence to chemoprophylaxis. The major risk factors adversely affecting survival were the severity of carditis, inadequacy of medical service, non-compliance to chemoprophylaxis, RF recurrence, poor socioeconomic status, and high prevalence of group A streptococci. It is concluded that there is no uniform "Oriental-type" of natural history of RF and RHD. The natural history varies greatly among countries as is true in other parts of the world.