Kawasaki disease is a leading cause of acquired heart disease in children in the developed world, characterised by acute systemic vasculitis, with a complex aetiology that remains poorly understood. Recent studies have highlighted the potential anti-inflammatory effects of Interleukin-35 in various proinflammatory and cardiovascular conditions. However, the relationship between Interleukin-35 gene polymorphisms and Kawasaki disease susceptibility, particularly in Chinese children, has not been well-explored.

In this study, we investigated the association between five Interleukin-35 single-nucleotide polymorphisms—rs2243115, rs2243123, rs583911, rs353698, and rs2302164—and Kawasaki disease in a cohort of Chinese children. A total of ninety-four Kawasaki disease patients and one hundred healthy controls were enrolled, with the Kawasaki disease patients further divided into subgroups based on the presence or absence of coronary artery lesions and incomplete or complete Kawasaki disease. Genotyping of Interleukin-35 polymorphisms was performed using the MassARRAY system.

The results showed the GT + GG genotypes and G allele of rs2243115 (T > G) were significantly more prevalent in Kawasaki disease patients with coronary artery lesions than in those without coronary artery lesions, suggesting a possible association with the development of coronary artery lesions. Additionally, the G allele of rs353698 (A > G) was more frequently observed in the incomplete Kawasaki disease group compared to the complete Kawasaki disease group, suggesting a possible association with the risk of incomplete Kawasaki disease.

Kawasaki disease is a leading cause of acquired heart disease in children with serious repercussions of coronary artery lesions. Recurrences of the disease are relatively rare in clinical practice. We present a case of recurrent Kawasaki disease, wherein the coronary artery lesions which were documented during the initial illness demonstrated complete regression over the following months, but reappeared with recurrence of the disease.

Recent studies have shown that elevated red blood cell distribution width is associated with poor outcome in cardiovascular diseases. In order to assess the predictive value of red blood cell distribution width, before treatment with intravenous immunoglobulins, for coronary artery lesions in patient with Kawasaki disease, we compared 83 patients with coronary artery lesions and 339 patients without coronary artery lesions before treatment with intravenous immunoglobulin. Clinical, echocardiographic, and biochemical values were evaluated along with red blood cell distribution width. A total of 422 consecutive patients with Kawasaki disease were enrolled into our study. According to receiver operating characteristic curve analysis, the optimal red blood cell distribution width cut-off value for predicting coronary artery lesions was 14.55% (area under the curve was 0.721; p=0.000); eighty-three patients (19.7%) had coronary artery lesions, and 70% of the patients with coronary artery lesions had red blood cell distribution width level >14.55%. Logistic regression analysis revealed that fever duration >14 days (odds ratio was 3.42, 95% confidence interval was 1.27–9.22; p=0.015), intravenous immunoglobulin resistance (odds ratio was 2.33, 95% confidence interval was 1.02–5.29; p=0.04), and red blood cell distribution width >14.55% (odds ratio was 3.49, 95% confidence interval was 2.01–6.05; p=0.000) were independent predictors of coronary artery lesions in patients with Kawasaki disease. In Conclusion, red blood cell distribution width may be helpful for predicting coronary artery lesions in patients with Kawasaki disease.