Risk of coronary abnormalities due to Kawasaki disease in urban area with small Asian population
S. T. Shulman, J. B. McAuley, L. M. Pachman, M. L. Miller and D. G. Ruschhaupt
The epidemiology of Kawasaki disease in the six-county Chicago metropolitan
area (total population, greater than 7,100,000 inhabitants) was
characterized by identifying cases, with onset occurring from 1979 to 1983,
inclusively, that had been studied by echocardiography. A retrospective
survey of the records from pediatric echocardiographic laboratories and
pediatric cardiologists at teaching hospitals, as well as a random sample
survey of nonteaching hospitals with pediatric beds in the metropolitan
area, was carried out. A total of 190 cases were identified, yielding an
annual mean minimum incidence of 5.95 per 100,000 children less than 5
years old. Cases occurred endemically with superimposed spring clusters in
1980 and 1983. As seen in other studies, the male-female ratio was 1.58:1,
and the peak incidence occurred in children between 1 and 2 years old, with
85% of cases occurring in children under 5 years of age. The racial
distribution of cases was as follows: whites, including Hispanics, 62%;
blacks, 32%; Asians, 5%; and half-white/half-Asian, 1%. Asians were
slightly overrepresented in that they made up only 1.7% of the study area
population. The annual minimum incidence for Asian Americans was 24.4 per
100,000 children less than 5 years old; this rate was significantly greater
than those for the other racial groups. Although few cases were observed in
Japanese-American children, the calculated annual minimum incidence in this
small group was approximately 44 per 100,000 children less than 5 years
old. The highest incidence was observed in several suburban Chicago zip
code areas, where annual rates as high as 84.7 per 100,000 children less
than 5 years old were documented. Coronary artery abnormalities were
diagnosed by echocardiography in 30 (16%) of 190 cases; the male-female
ratio of patients with such abnormalities was 2.75:1. Whites and children
under 1 year of age demonstrated the highest incidence of coronary artery
abnormalities. White children under 1 year of age appeared to be at
particularly high risk for development of coronary abnormalities, with 11
(41%) of 27 white infants manifesting such findings by echocardiography.
These infants may represent a subgroup of patients who would benefit
particularly from therapy with intravenous gamma globulin for prevention of
coronary abnormalities and who require particularly close follow-up care.
