Association of platelet level and white blood cell level with coronary artery lesions persistence among patients with Kawasaki disease

OBJECTIVES: Kawasaki disease (KD) is an acute febrile multisystem vasculitis with the most serious complication being coronary artery lesions (CALs). However, factors related to CALs persistence remain unclear. This study investigated the association between platelet (PLT) level and CALs persistence at one month in KD patients who had CALs before intravenous immunoglobulin (IVIG) treatment, and explored potential interaction factors. METHODS: We conducted a study of 170 KD patients with CALs prior to IVIG treatment. CALs persistence was defined as an increase or no decrease in coronary artery Z-scores at one-month follow-up. Using logistic regression, we assessed the independent association of PLT level (categorized as < 300 × 10^9/L, 300-450 × 10^9/L and ≥450 × 10^9/L) and their interaction with WBC level on CALs persistence. RESULTS: Among the patients, 74 (43.5%) had CAL persistence at one month. A dose-response relationship was observed between higher PLT level and CALs persistence at one month. Patients with PLT ≥450 × 10^9/L had increased odds of CAL persistence at one month (adjusted OR = 4.860, 95% CI: 1.278, 18.487). We observed a nominally significant interaction between PLT and WBC level (P = 0.049). Exploratory analysis suggested higher odds in patients with both PLT ≥450 × 10^9/L and WBC >15 × 10^9/L (adjusted OR = 6.101, 95% CI: 0.620, 60.012). CONCLUSION: A high PLT level (≥450 × 10^9/L) is independently associated with CAL persistence at one month in KD patients with pre-IVIG CALs. The coexistence of high PLT and high WBC level may be associated with increased odds of CALs persistence at one month, requiring confirmation in larger prospective studies.