Is there an association between Kawasaki disease and Chlamydia pneumoniae?

The clinical and epidemiological features of Kawasaki disease (KD) are consistent with an infectious cause. Because chronic infection with Chlamydia pneumoniae has been implicated in the pathogenesis of atherosclerosis, it has been suggested that it may also be involved in the pathogenesis of KD. Paired sera (baseline pretreatment and 1 year after treatment with intravenous immunoglobulin [IVIG]) from 26 children with KD and 29 age-matched controls were examined by microimmunofluorescence (MIF) serology and immunoblotting. There were no significant differences in the prevalence of anti-C. pneumoniae IgG, IgA, or IgM between cases and controls; however, 73%-85% of sera from cases and controls reacted with C. pneumoniae proteins by immunoblotting. There was significantly more reactivity in the pre-IVIG, but not post-IVIG, KD sera compared with sera from controls to proteins at 72-74 kDa and 74-76 kDa. They may be heat shock proteins. The results of this study do not support an association between KD and C. pneumoniae on the basis of MIF and immunoblot analysis.