Reported cases of multisystem inflammatory syndrome in children aged 12–20 years in the USA who received a COVID-19 vaccine, December, 2020, through August, 2021: a surveillance investigation

Cardiac Complications After SARS-CoV-2 Infection and mRNA COVID-19 Vaccination — PCORnet, United States, January 2021–January 2022

“…Incidence of three cardiac outcomes (myocarditis; myocarditis or pericarditis; and myocarditis, pericarditis, or MIS) were defined using International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) diagnostic codes § within 7-day or 21-day risk windows after the index date; persons who had received any of these diagnoses during the year preceding the index date were excluded. The outcome including MIS was only assessed for the infection cohort because the rare reports of MIS after mRNA COVID-19 vaccination typically had evidence of previous SARS-CoV-2 infection ( 8 ); a 42-day risk window also was used for this outcome to allow for a possible long latency between infection and diagnosis of MIS ( 6 ). ¶ Because persons with MIS who have cardiac involvement might only receive an ICD-10-CM code for MIS, rather than myocarditis or pericarditis, this combined outcome allowed for a comprehensive capture of potential cardiac complications after infection.…”

Liposome encapsulated clodronate mediated elimination of pathogenic macrophages and microglia: A promising pharmacological regime to defuse cytokine storm in COVID-19

“…Ample reports indicate that COVID-19 vaccinated individuals have considerably increased risk of reinfection to SARS-CoV-2 [123] , [124] . Notably in some individuals COVID-19 vaccinated developed destructive macrophage activation and multisystem inflammatory disease similar to the pathogenesis seen in COVID-19 [125] , [126] . In some cases, the immoral immune responses of COVID-19 vaccinations appear to be associated with chronic activation of various immune cells including macrophages resulting in cytokine storm and unforeseen adverse effects including MAS and ARDS [127] .…”

Reversible Autoimmune Cardiomyopathy Secondary to a Vaccine-Induced Multisystem Inflammatory Syndrome

“…Multisystem inflammatory syndrome (MIS) is an uncommon condition that could worsen the outcome in COVID-19 patients. However, there is a post-COVID-19-MIS established in the literature; it usually manifests four to six weeks after the acute phase of the infection, but there is literature exposing the risk period up to sixteen weeks [ 3 , 4 ]. In April 2020, this syndrome was recognized in the United Kingdom (UK) and named Pediatric Inflammatory Multisystem Syndrome ( i.e., Multisystem Inflammatory Syndrome in Children - MIS-C) [ 5 , 6 ].…”