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

Abstract

This report presents 2 pediatric cases of multisystem inflammatory syndrome in children/adults (MIS-C/A) post-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 one had classic Kawasaki Disease (KD) features. Both responded well to intravenous immunoglobulins and/or systemic corticosteroids. Both children were positive only for SARS-2-CoV anti-spike (S) (and not for anti-nucleocapsid (NC)) antibodies consistent with a post-vaccine and not a post-infection event. Surveillance for rare adverse events (AE) following immunization should continue especially now that SARS-CoV-2 vaccination is approved in the 5-11 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).

COVID-19 mRNA Vaccines: From Inflammation to Hyperinflammation

“…Multisystem MIS following COVID-19 vaccination (MIS-V) remain rare event [186], but it is a serious adverse event. There have been identified 12 cases of hyper-inflammatory syndrome following COVID-19 mRNA vaccines (now MIS-V) in 12-17-year-old children in France, with multisystemic involvement [187], and two pediatric cases with neurological involvement in Italy [186]. Two other cases have recently been described…”

“…Multisystem Inflammatory Syndrome in children (MIS-C) and adult (MIS-A) are late complication of SARS-CoV-2 infection [181][182][183][184][185]. MIS following COVID-19 mRNA vaccines (MIS-V) it is a serious adverse event and there are many pediatric case reports that begin 4-6 weeks after the first vaccine dose [186][187][188].…”

A cursed goodbye kiss from severe acute respiratory syndrome-coronavirus-2 to its pediatric hosts: multisystem inflammatory syndrome in children

“…Considering that vaccination can increase only antispike antibodies, it has been confirmed that the boy developed MIS-C following the infection [109]. In addition, children who developed MIS-C because of vaccination were also reported, which has been confirmed by sub-antibody measurements [110,111]. Given the rarity of the disease and these paradoxical events, the harm-benefit balance of the vaccines against MIS-C remains somewhat unclear.…”

Two Pediatric Cases of Multisystem Inflammatory Syndrome with Overlapping Neurological Involvement Following SARS-CoV-2 Vaccination and Unknown SARS-CoV2 Infection: The Importance of Pre-Vaccination History

“…Recently, a multisystem inflammatory syndrome following SARS-CoV-2 vaccination (MIS-V) both in adults [ 7 ] and children [ 8 , 9 ] has been described, raising some concerns in the scientific community which, in conjunction with international regulatory agencies, is actively monitoring this condition [ 8 , 9 ]. MIS-V is a rare entity, and the exact incidence, prevalence and pathophysiology are still unknown.…”

“…In particular, neurological adverse events following vaccination are generally mild and transient, although rare major neurological complications, such as cerebral venous sinus thrombosis, Bell's palsy, acute transverse myelitis, acute disseminated encephalomyelitis, and acute demyelinating polyneuropathy, have been described [5,6] Recently, a multisystem inflammatory syndrome following SARS-CoV-2 vaccination (MIS-V) both in adults [7] and children [8,9] has been described, raising some concerns in the scientific community which, in conjunction with international regulatory agencies, is actively monitoring this condition [8,9]. MIS-V is a rare entity, and the exact incidence, prevalence and pathophysiology are still unknown.…”