Possible relationship between streptococcal pyrogenic exotoxin A and Kawasaki syndrome in patients older than six months of age.
BACKGROUND
We previously investigated antibody titers against four kinds of superantigens [streptococcal pyrogenic exotoxin A (SPEA), streptococcal pyrogenic exotoxin C, toxic shock syndrome toxin-1 and staphylococcal enterotoxin B] in patients with Kawasaki syndrome (KS) younger than 6 months of age and reported a relationship between toxic shock syndrome toxin-1 and KS patients. In this study we have investigated antibody titers in KS patients older than 6 months of age.


METHODS
Serum of 81 patients with KS older than 6 months of age, before intravenous gamma-globulin therapy, and 88 normal age-matched children were used in this study. The IgG antibody titers against four kinds of superantigens were measured with an enzyme-linked immunosorbent assay.


RESULTS
The KS patients showed significantly elevated mean SPEA titer (P = 0.006) and significantly higher incidence of high SPEA (P = 0.0024) compared with the controls. The SPEA titer in KS patients showed a significant positive correlation with the number of days from onset of illness (P = 0.0002).


CONCLUSIONS
The elevated antibody titer against superantigens of KS patients older than 6 months of age was different from that of KS patients younger than 6 months of age. Our results suggest that KS patients' exposure to SPEA occurred a few weeks before the onset of KS. SPEA may be one of the possible etiologic agents of KS among patients older than 6 months of age in Kagoshima, Japan.
D000367:Age Factors; D000907:Antibodies, Bacterial / Q000032:analysis*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005098:Exotoxins / Q000032:analysis / Q000378:metabolism*; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D009080:Mucocutaneous Lymph Node Syndrome / Q000453:epidemiology / Q000276:immunology*; D011336:Probability; D011379:Prognosis; D011446:Prospective Studies; D011749:Pyrogens / Q000276:immunology* / Q000378:metabolism; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013210:Staphylococcus / Q000276:immunology* / Q000378:metabolism; D018709:Statistics, Nonparametric; D018089:Superantigens / Q000032:analysis*
D000907:Antibodies, Bacterial; D005098:Exotoxins; D011749:Pyrogens; D018089:Superantigens