Kawasaki syndrome: issues in etiology and treatment.

To date several infectious agents have been proposed to cause KS, but none of these agents have been consistently demonstrated in KS. Epidemiologic studies suggest that host factors, including age, race, and sex, play an important role in KS. One hypothesis is that primary infection or activation of a latently infecting agent may play a role in KS; the other factors may be related to KS by activating such an agent. The 13 to 30 days between rug or carpet cleaning and onset of KS may represent an incubation or induction period for an infectious agent. The presence of certain epidemiologic risk factors and infectious agents in some outbreaks and not in others is puzzling (Table 4). Nevertheless, there are precedents for intermittently occurring epidemiologic risk factors, as with hepatitis, in which enteral and parenteral transmission can occur with the associated risk factors for each mode of transmission. The mechanisms by which the intermittently associated epidemiologic risk factors of antecedent illness and exposure to recently shampooed or spot-cleaned rugs or carpets relate to KS remain unknown. Similarly, how living near a body of water relates to KS awaits further clarification. The cause of KS remains a fascinating and controversial question, and the answer continues to grow in importance with the increasing health impact of this disease. As more data accumulate, high-dose IVIG therapy appears to brighten the outlook for KS patients as we await identification of the cause of this disease and more definitive treatment. Because we have just begun to use this therapy in KS, it is most important that any adverse effects that may occur be brought to the attention of the medical community. One question regarding KS will remain unanswered for years, that is, long-term sequelae of the disease in both treated and untreated patients. There have been a few anecdotal reports of onset of exertional angina in children several years after onset of KS. Histopathologic studies of coronary vessels of five KS patients who died of causes unrelated to KS and who apparently had completely recovered from the illness revealed abnormalities of the coronary vessels, primarily changes in the intima and internal elastic lamina. This has led to speculation that patients with a history of KS may have some coronary artery lesions not serious enough to be clinically detectable or to become an immediate cause of death but which may lead to juvenile arteriosclerosis.(ABSTRACT TRUNCATED AT 400 WORDS)