BACKGROUND AND OBJECTIVES: Kawasaki disease (KD) is a febrile acute multi-systemic vasculitis, which develops into carditis and coronary aneurysm. This study was performed to investigate cardiac troponin T (cTnT), troponin I (cTnI) and creatinine kinase-MB fraction (CK-MB) for diagnostic and prognostic value in acute KD before IVGG (intravenous gamma globulin). SUBJECTS AND METHODS: The KD group comprised of 45 patients hospitalized between Jan. 2000 and Jul. 2003, with 25 non KD febrile illness subjects as controls. The KD group was subdivided into groups A (persistent normal coronary artery, n=20), B (abnormal coronary artery, n=19) and C (carditis, n=6) according to the initial echocardiography. The cTnT, cTnI and CK-MB levels were measured and compared. RESULTS: Comparing the KD and control subjects, the cTnT (0.0101+/-0.0030 vs. 0.0090+/-0.0000 ng/mL, p=0.025) and cTnI (0.0662+/-0.0581 vs. 0.0143+/-0.0112 ng/mL, p=0.000) were significantly elevated in the KD patients. However, all the data were within normal reference ranges. In a comparison among the KD groups, the number of infants, total fever duration and IVGG re-treatment were significantly higher in group B (p=0.021, 0.046 and 0.007, respectively). There were no significant differences in the cTnT, cTnI and CK-MB levels between the 3 groups. The CK-MB and cTnI levels were slightly elevated in group B compare to groups A+C, but these were not statistically significant. The CK-MB, cTnT and cTnI levels were slightly elevated in those with cardiac abnormalities (groups B+C) compare to group A, but these were not significant. The cTnT and cTnI levels were significantly decreased in the subacute phase (p=0.034 and 0.000, respectively). CONCLUSION: The levels of cTnT, cTnI, CK-MB were not very useful tools for detecting and predicting subsequent cardiac damage in KD patients. However, the cTnI level appears to be a more sensitive marker than the cTnT or CK-MB levels in KD patients.