201 - KAWASAKI DISEASE, MULTISYSTEM INFLAMMATORY SYNDROME IN CHILDREN AND COVID-19 IN A TERTIARY PEDIATRIC HOSPITAL IN MONTREAL, CANADA

Background: During the SARS-CoV-2 (COVID-19) pandemic speculation arose on possible association between Kawasaki Disease (KD), Multisystem Inflammatory Syndrome in Children (MIS-C) and COVID-19. This retrospective study describes the demographics and clinical course of children diagnosed with KD or MIS-C during COVID-19 pandemic.

Methods: Retrospective chart reviews on children hospitalized at CHU Sainte Justine in Montreal, Canada, for KD (n=74) or MIS-C (n=81) between 01/2020 and 12/2022.

Results: Only 24.3% KD patients tested rt-PCR positive for COVID-19 or were exposed to a positive contact before symptom onset vs. 38.27% MIS-C patients (of note, 23.0% KD and 41.20% MIS-C were unknown. KD patients were 3.61±3.56 years old vs. MIS-C 8.49±4.21 years (p < 0.0001); 58.11% KD vs. 61.73% MIS-C were male. 1 KD case required a 1-day pediatric intensive care unit (PICU) admission vs. 53.1% MIS-C (p < 0.0001) with an average PICU duration of 3.05±2.03 days. Most common KD clinical criteria (Table-1) observed with MIS-C were conjunctivitis and skin rash with a Median of 4 [1-5] criteria in KD vs. 2 [0-5] criteria in MIS-C. Fever duration was 8.10±3.28 days for KD vs. 7.84±3.69 for MIS-C (p=0.64) and hospital duration 4.45±4.11 days in KD vs. 6.70±3.40 in MIS-C (p < 0.001). Coronary dilatations with a Z-score of greater than or equal to 3.0 occurred in 22.97% of KD patients vs. 11.11% of MIS-C patients (p=0.05). Cardiac severity, defined as coronary artery aneurysms with a Z-score greater than or equal to 3.0 and/or cardiogenic shock, was observed most often in French-Canadians, Asians, and mixed ethnicity children who had KD (Figure-1); all mixed ethnicity cases had 1 French Canadian parent and 50% of the mixed-ethnicity cases had 1 European parent (Table-2). In contrast, in children with MIS-C, the incidence of cardiac severity was highest in African, Haitian and Arab ethnic groups compared with Asian, European, French Canadian, Latin children and children of mixed ethnic origin.
Conclusion: Clinical course of patients with KD and MIS-C during the SARS-CoV-2 pandemic suggest that MIS-C patients were older and tested COVID-19 positive or were exposed to a COVID positive contact in a higher proportion compared to KD as well as required more PICU admissions. A trend towards less coronary complications associated with MIS-C did not reach statistical significance. Cardiac severity was more prevalent in French Canadian, Asian and mixed ethnic children with KD and in African/Haitian and Arab children with MIS-C.