Assessment of Platelet Thrombus Formation under Flow Conditions in Patients with Acute Kawasaki Disease

To assess platelet thrombus formation (PTF) under flow conditions in patients with Kawasaki disease. Previously available platelet activation data were limited for nonphysiological shear stress condition. The total thrombus-formation analysis system (T-TAS) was developed for quantitative PTF analysis.

In total, 33 patients with acute Kawasaki disease were assessed. Whole blood samples, obtained immediately before treatment and 1 week and 1 month after treatment, were assessed using the T-TAS with a collagen-coated platelet chip under high shear values (1000 s^-1 [PL₁₂] and 2000 s^-1 [PL₂₄]). Measures, such as time to reach 5 kPa above the base pressure (T_5+α) and area under the curve for flow pressure curve for 10 minutes (AUC₁₀) were analyzed to quantify PTF.

Immediately before treatment, the median PL₁₂-T_5+α and PL₂₄-T_5+α were 3.3 minutes (IQR 2.0-4.5) and 1.3 minutes (0.9-1.9), respectively, and both values were significantly lower in adult controls (3.5 minutes [2.9-6.4] and 2.8 minutes [1.8-4.8]; P = .015 and P < .001, respectively). In addition, the PL₁₂-AUC₁₀ (151.7 U [94.5-279.9]) significantly decreased in adult controls (234.1 U [110.5-306.5], P = .007). By contrast, at 1 week and 1 month after the start of treatment, the T_5+α was longer, and the PL₁₂-AUC₁₀ and PL₂₄-AUC₁₀ decreased.

In patients with acute Kawasaki disease, the PTF had an early onset and weak stability.