The Clinical and Molecular Findings of Patients with Multisystem Inflammatory Syndrome in Children (MIS-C)

Abstract

Background: several children with COVID-19 disease present with fever, gastrointestinal symptoms, rash, conjunctivitis, mucosal changes, shock, and myocardial dysfunction, called multisystem inflammatory syndrome in children (MIS-C), similar to incomplete Kawasaki disease or toxic shock syndrome. The unclear pathophysiology of MIS-C prompts clinical and genetic evaluation of the patients. Method: In the present study, patients with MIS-C disease who were referred by medical specialists of Imam Ali Hospital of Alborz in 2020-2021 were included. The clinical manifestations and laboratory findings of enrolled patients were evaluated, and the genetic analysis was performed by whole exome sequencing (WES), further confirmed by Sanger sequencing. Results: Among 11 patients diagnosed with MISC, six patients (54.5%) were male, and the mean (SD) age of participants was 6.55 (±2.81) years. The most prevalent clinical presentations included fever (100%), rash (82%), bilateral non-purulent conjunctivitis (73%), and mucous membrane changes (64%). The only patient with genetic alterations was an 8-year-old boy with a homozygous missense variant of the ATP6AP1 gene and a heterozygous likely pathogenic canonical splice site variant of the M1B1 gene. Conclusion: Although the young age of patients with MIS-C and their autoinflammatory presentations are similar to patients with inborn errors of immunity, the results indicate that most patients with MIS-C do not have genetic mutations.