Characteristics of pediatric multi-system inflammatory syndrome (PMIS) associated with COVID-19: a meta-analysis and insights into pathogenesis

OBJECTIVES: There was an outbreak of pediatric multisystem inflammation syndrome (PMIS) was observed in multiple countries recently, and this syndrome was suspected to be associated with SARS-CoV-2 infection. At present, there is still no standardized diagnostic criteria and treatment regimen for PMIS, while the etiology and pathogenesis still remain unclear. METHODS: We performed a systematic review on PubMed and Embase from the time of inception to June 24th 2020 in order to find relevant cases. RESULTS: There are seven studies included, and 80% of patients suffered persistent fever and 90% appeared gastrointestinal symptoms. IgG antibody against SARS-CoV-2 was positive on 81% of patients, while 37% of the patients were nucleic acid positive. C-reactive protein, IL-6 and PCT were elevated and intravenous immunoglobulin was a routine treatment for PMIS. There were more than half of patients required inotropic supports and mechanical ventilation were applied to 33% of patients. The median length of hospital stay was 10.66 days and 74% had admitted to accept intensive care. CONCLUSIONS: Our study documented three common types of PMIS clinical presentation: persistent fever and gastrointestinal symptoms, shocked with heart dysfunction and Kawasaki disease-like syndrome. PMIS patients proved with a marked inflammatory state were possibly associated with SARS-CoV-2 infection.