Abstract
BACKGROUND: This study aims to inform the enhancement of prevention and control strategies for Kawasaki disease (KD) by conducting a retrospective analysis of its clinical features in the context of the Omicron pandemic. METHODS: KD cases from the three years preceding the Omicron pandemic were categorized as the control group, while cases occurring during the Omicron pandemic were designated as the observation group. Comparative analyses were performed between these groups, focusing on demographic characteristics such as the proportion of hospitalizations for KD, age, gender, and place of residence, as well as clinical data encompassing symptoms, laboratory findings, imaging results, diagnosis and treatment, and prognosis. RESULTS: A total of 407 children participated in the study, with 180 allocated to the observation group and 227 to the control group. During the Omicron outbreak, the proportion of KD among hospitalized children gradually declined, with a more pronounced decrease observed in rural areas compared to urban areas. No significant differences were noted in age, sex, or season between the two groups. Compared to the control group, the observation group demonstrated a lower incidence of conjunctival congestion, extremity changes, mucosal alterations, and joint and urinary system damage (P < 0.05). Furthermore, our study identified significantly elevated levels of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), increased rates of valve regurgitation and pericardial effusion, and prolonged recovery time for inflammatory markers in the observation group (P < 0.05). Additionally, no statistically significant differences were observed in coronary lesions during the one-year follow-up period. CONCLUSION: Because of the Omicron pandemic, the proportion of children hospitalized for KD decreased. Meanwhile, the incidence of clinical symptoms was low, and the inflammatory reaction was heavy. Moreover, there was a trend towards increased IKD and IVIGR and no difference in coronary lesions at 1 year of follow-up. This might indicate that we should pay attention to early diagnosis of IKD and treatment of IVIGR to prevent and treat KD. TRIAL REGISTRATION: Retrospectively registered.