This deadly complication of COVID-19, pediatric multisystem inflammatory syndrome (MIS-C), which has symptoms similar to Kawasaki disease, has reportedly affected several hundred children, adolescents and young adults since the start of the pandemic. pandemic. The study led by the Murdoch Children’s Research Institute (MCRI) and the University of Melbourne deciphers the mechanisms of disease in children with COVID-19 who develop MIS-C.
The main author, Dr. Conor McCafferty, a researcher at MCRI, specifies that the main triggers of severe COVID-19 in children are blood clotting and the reaction of proteins of the immune system to the virus: “if children are in general less susceptible to COVID-19 and have milder symptoms, some develop a very severe form, the specific pathways of which we have just discovered”.
A blood signature from MIS-C
Certain characteristics of blood clotting and immune proteins thus form a signature of MIS-C, according to this analysis of blood samples from 20 healthy children and 33 SARS-CoV-2 infected children with MIS-C (monitored at the Necker-Enfants Malades Hospital, Paris). The analysis, conducted using proteomics, an experimental approach that allowed researchers to simultaneously study nearly 500 proteins circulating in the blood, reveals:
- 85 and 52 proteins, respectively specific to MIS-C and acute respiratory distress syndrome;
The identification of these hallmark proteins also provides new understanding of the processes underlying severe forms of COVID-19 in children. Finally, in practice, it might allow the development of diagnostic tests for the early identification of children at high risk of serious forms.
“Knowing the mechanisms associated with severe COVID-19 in children and how children’s blood clotting and immune systems respond to the virus will not only help us diagnose and detect acute cases of COVID-19 but will also allow us to develop more targeted treatments”.
