Objective:

To evaluate temporal changes in clinical phenotype and coronary involvement among children with Kawasaki disease across the COVID-19 pandemic.

Approach:

• Study Design: Retrospective single-center study analyzing children diagnosed with Kawasaki disease from January 2015 to February 2024, categorized into pre-pandemic, pandemic, and post-pandemic periods.
• Data Collection: Demographic characteristics, clinical features, laboratory findings, treatment response, and echocardiographic outcomes were compared among the three periods.

Key Findings:

• During the pandemic, C-reactive protein and erythrocyte sedimentation rate were significantly higher (exact values not provided).
• Thrombocytosis was more frequent during the pandemic, while cervical lymphadenopathy was less common.
• In the post-pandemic period, time to diagnosis was shorter, and the number of clinical findings at presentation was higher.
• Elevations in liver transaminases were more frequent in the post-pandemic period.
• Rates of intravenous immunoglobulin resistance, length of hospital stay, coronary artery involvement, and valvular regurgitation were similar across periods.

Interpretation:

The COVID-19 pandemic was associated with changes in the inflammatory and clinical expression of Kawasaki disease without clear differences in cardiac outcomes.

Limitations:

• Retrospective design may limit the ability to draw definitive conclusions.
• Limited sample size may affect the generalizability of the findings.

Conclusion:

The findings indicate a greater effect on disease phenotype than on overall disease course.