The occurrence of coronary artery lesions in Kawasaki disease based on C-reactive protein levels: a retrospective cohort study

BACKGROUND: This study aimed to assess the occurrence of coronary artery lesions (CAL) in patients with Kawasaki disease (KD) according to serum C-reactive protein (CRP) levels. METHODS: This retrospective analysis was based on the nationwide survey of KD conducted in the Republic of Korea between 2015 and 2017. We enrolled 9131 patients and defined low (< 3 mg/dL) and high (≥3 mg/dL) CRP groups. Demographic data, clinical characteristics, z-scores, and scores based on the Japanese criteria for CAL were compared between the two groups. Logistic regression analysis was used to identify CAL risk factors. RESULTS: The low CRP group accounted for 23% of patients. The mean age at diagnosis was higher in high CRP group compared to the low CRP group (34.4 ± 24.9 vs 31.7 ± 24.8 months, p < 0.001). Fever duration before treatment was not significantly different between the two groups (5.1 ± 1.7 days vs. 5.2 ± 2.1 days; p = 0.206). A non-response to intravenous immunoglobulin treatment was found in 1377 patients (20.1%) and 225 patients (11.7%) in the high and low CRP groups, respectively (p < 0.001). CAL were found in 12.9 and 18.3% of the high and low CRP patients, respectively (p < 0.001), based on z-scores; and in 9.9 and 12.5%, respectively (p = 0.001), based on the Japanese criteria in the acute phase. The giant coronary artery aneurysm occurrence ratio was similar between groups (p = 1.0). CONCLUSIONS: CAL occurred in patients with both high and low CRP. Therefore, patients with KD should be carefully monitored regardless of their CRP levels. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12969-021-00566-6.