Unraveling the complexity in diagnosis and management of multisystem inflammatory syndrome in children with Kawasaki disease mimicry: a case report.

Introduction and importance: COVID-19 can lead to a severe complication in children known as multisystem inflammatory syndrome (MISC), often mimicking Kawasaki disease (KD). This study addresses the diagnostic challenges and management of MISC. Case presentation: A 6-year-old female presented with fever, vomiting and rash. Clinical examination revealed cervical lymphadenopathy, periungual desquamation, lip fissures and abdominal tenderness. Echocardiography showed RCA dilatation. These findings suggested multisystem involvement and fulfilled the criteria of typical KD. The treatment was started accordingly with IVIG and empirical antibiotics. However, the confirmation of presence of SARS-CoV-2 antibody led to substantial shift of diagnosis to MISC Despite initial treatment, fever persisted, thus, Intravenous steroid was started which led to significant clinical improvement, rendering her almost asymptomatic in 2 weeks. Clinical discussion: Distinguishing MISC from KD is critical. Diagnostic criteria, epidemiology, and lab markers play a vital role. The case underscores the importance of recognizing subtle differences for accurate diagnosis and effective management. Conclusion: MISC, resembling KD, poses diagnostic complexities. This case emphasizes the need for clinicians to consider MISC in children with persistent fever and multisystem involvement post-COVID-19 exposure. Timely diagnosis and intervention are paramount for favorable outcomes in this emerging pediatric condition, urging increased awareness and reporting among healthcare professionals.