[Kawasaki disease versus Multisystem Inflammatory Syndrome COVID-19 with Kawasaki disease phenotype. Single-center experience].

In pediatrics, a process called Pediatric Inflammatory Multisystem Syndrome (PIMS) associated with recent infection by SARS-CoV-2 virus has been observed. One of its variants presents similarities with Kawasaki disease (KD).
Objective: to compare the clinical presentation, laboratory testing, and evolution of KD with PIMS Kawasaki phenotype (PIMS-KD) in patients hospitalized before the pandemic, compared with the pandemic period.
Patients and Method: Cross-sectional study in two groups of patients at the Hospital Exequiel González Cortés: typical KD (group 1) and PIMS-KD (group 2). Data on demographic, clinical, and biochemical details were collected, as well as echocardiogram, treatment, and evolution records. IgG and IgM serology for SARS-CoV-2 was performed in both groups.
Results: In the KD group and the PIMS-KD group, 20 and 33 patients were analyzed, respectively. There were differences in age, days of fever, count of leukocytes, lymphocytes, and platelets, erythrocyte sedimentation rate (ESR), and hospital stay. In 25% of the KD group, there were alterations in the echocardiogram and, in the PIMS-K group, all patients received corticosteroids and 25 patients received intravenous immunoglobulin (IVIG). In both groups, a favorable clinical evolution was observed, characterized by the absence of complications and mortality.
Conclusions: Based on the data obtained in our study, the importance of the epidemiological link is emphasized as an essential factor in differentiating between both pathologies, highlighting the need to consider factors such as age, duration of fever, count of leukocytes, lymphocytes, and platelets, and degree of cardiac involvement, for a differential evaluation between patients with PIMS-KD versus KD.