Diagnosis and therapy of Kawasaki disease in children.

awasaki disease, a generalized vasculitis of unknown etiology, is a leading cause of acquired heart disease in children in the United States.It occurs more often in boys than in girls, with a ratio of about 1.5:1.Eighty percent of cases occur in children less than 5 years of age, and most are in children under 2. The onset of the disease is rare after 8 years of age.Less than 2% of patients have recurrences.'Within the United States, children of all racial backgrounds are affected, although the highest incidence is in children of Asian ancestry.Kawasaki disease has been reported worldwide.Kawasaki disease was initially described by Dr. Tomisaku Kawasaki2 in 1967 in Japan and was found to be an important cause of cardiac disease in children shortly thereafter.More than 115,000 cases were reported in Japan from that time through 1991 (T.Ka- wasaki, written communication, 1992).Annual attack rates in Japan have been as high as 67 per 100,000 children under 5 years of age.3In the United States annual attack rates vary between 6-9 per 100,000 children less than 5 years of age.4-6This is reflected in an estimate of at least 2,000 cases per year in the United States.6In the United States Kawasaki disease occurs year- round, with a greater number of cases observed in winter and spring.Reports from Japan, where the most complete epidemiological surveillance data have been collected, show that epidemics occurred in 1979, 1982, and 1985.Epidemics have also been reported in the United States and other countries.The epidemiology of Kawasaki disease suggests that a microbial agent is the cause of this disease.The clinical presentation is also highly suggestive of an infectious etiology; rickettsiae, viruses (primarily Epstein-Barr vi- rus and retroviruses), several bacteria (e.g., group A streptococci, other streptococci, and propionibacteria), and candidae have been suggested as etiologic agents.To date, however, an etiologic agent has not been documented.Epidemiological observations suggest that Kawasaki disease may be associated with living near bodies of water or exposure to house dust mites or recently shampooed carpets.Critical data to substanti- ate these possible associations are lacking.Although an infectious etiology has been suggested, person-to-per- son transmission has not been documented, even in day-care centers, a common source for outbreaks has not been defined, and cases among siblings are very rare.This statement discusses the diagnosis of Kawasaki disease and its treatment during the acute phase.Long- term follow-up of patients with cardiac involvement will be addressed in a subsequent publication by this committee. Diagnosis of Kawasaki DiseaseIn the absence of a specific diagnostic test for Ka- wasaki disease, clinical criteria have been established to assist the physician in making the diagnosis.7Other clinical and laboratory findings observed in patients with this disease are frequently helpful.Table 1 de- scribes the clinical and laboratory features of Kawasaki disease. Principal Clinical FindingsFever and at leastfour ofthefiveprincipal clinicalfeatures should be present to establish the diagnosis of Kawasaki disease.Patients with fever and fewer than four principal features can be diagnosed as having Kawasaki disease when coronary artery disease is detected by two-dimen- sional echocardiography or coronary angiography.The fever is generally high and spiking, and persists in the untreated patient for 1-2 weeks or longer.With appropriate treatment the fever usually resolves in a short period of time.Kawasaki disease should be con- sidered in the differential diagnosis of a young child with unexplained fever.Changes in the extremities are distinctive.