Multisystem Inflammatory Syndrome Following SARS-CoV-2 Vaccination in Two Children

Pediatrics. 2022 Aug 1;150(2):e2021055956. doi: 10.1542/peds.2021-055956.


This report presents 2 pediatric cases of multisystem inflammatory syndrome in children and adults (MIS-C/A) post severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination (MIS-V). Both children presented with MIS-V within 6 weeks of receiving their first and only dose of Pfizer-BioNTech's SARS-CoV-2 vaccine. The first patient had symptoms of MIS-C/A with peri-myocarditis and shock, and the second 1 had classic Kawasaki disease features. Both responded well to intravenous immunoglobulins and/or systemic corticosteroids. Both children were positive only for SARS-2-CoV antispike (S) (and not for antinucleocapsid [NC]) antibodies consistent with a postvaccine, and not a postinfection, event. Surveillance for rare adverse events following immunization should continue, especially now that SARS-CoV-2 vaccination is approved in the 5 to 11 year age group that has had the highest risk of developing MIS-C post SARS-CoV-2 infection. Our patients did not receive any further SARS-CoV-2 vaccines. Our report highlights the importance of measuring differentiating antibodies (anti-S and anti-NC) that can be used within a specific timeframe to help determine if a patient has MIS-V post vaccine (only anti-S present), or MIS-C/A post SARS-CoV-2 infection (both anti-S and anti-NC present).

Publication types

  • Case Reports

MeSH terms

  • COVID-19 Vaccines* / adverse effects
  • COVID-19* / complications
  • COVID-19* / prevention & control
  • Child
  • Humans
  • SARS-CoV-2
  • Systemic Inflammatory Response Syndrome
  • Vaccination / adverse effects


  • COVID-19 Vaccines

Supplementary concepts

  • pediatric multisystem inflammatory disease, COVID-19 related