Cutaneous Clues in Kawasaki Disease: Clinical Implications and Differential Diagnosis with Multisystem Inflammatory Syndrome in Children

Kawasaki disease (KD) and multisystem inflammatory syndrome in children (MIS-C) are pediatric inflammatory conditions with overlapping mucocutaneous features that may complicate early diagnosis. We performed a narrative review of the literature to characterize and compare cutaneous manifestations reported in children with KD and MIS-C and to assess their diagnostic relevance. Published studies describing dermatologic findings in patients aged 0–18 years were reviewed. The analysis revealed a broad heterogeneity of skin manifestations in both conditions, ranging from classic polymorphous rash and acral erythema to atypical presentations, including annular, psoriasiform, vesiculobullous, urticarial, and erythema nodosum-like lesions. Reactivation at Bacillus Calmette–Guérin vaccination sites and associated mucocutaneous findings, such as conjunctivitis and oral changes, emerged as supportive diagnostic clues, particularly for incomplete KD. Considerable overlap in cutaneous phenotypes between KD and MIS-C was observed, especially in patients with persistent fever and systemic inflammation, highlighting the risk of diagnostic delay. These findings underscore the importance of recognizing atypical dermatologic patterns as part of an integrated diagnostic approach, as delayed identification may increase the risk of cardiovascular complications. Early recognition of cutaneous clues can support timely initiation of immunomodulatory therapy and improve clinical outcomes.