In the first months after Covid emerged, doctors were baffled by rare and severe responses to the virus in some children, whose symptoms included lung disease, blood clotting and heart damage.
Two years later and researchers led by the Murdoch Children’s Research Institute [MCRI] in Melbourne have uncovered the proteins involved in these acute inflammatory responses in children.
MCRI haematology researcher Conor McCafferty said blood samples were taken from 33 children affected by either multi-system inflammatory syndrome or acute respiratory distress syndrome after they contracted Covid-19.
Children with Covid-19 who develop multisystem inflammatory syndrome often suffer from fever, abdominal pain, vomiting, skin rash, heart disease or conjunctivitis. Children who develop acute respiratory distress syndrome may suffer organ damage due to a lack of oxygen in the blood.
These blood samples were compared with samples from 20 healthy children.
“What we were doing was trying to look at all of the proteins in their blood,” McCafferty said. “So a lot of people hear about genomics, which is looking at all of the genes in the body. We were doing proteomics, which involved looking at all of the proteins in the blood so we could try and map out what was happening.”
They found the children affected by the syndromes contained specific proteins in their blood not seen in the healthy children.
“Our research was the first to uncover the specific blood clotting and immune protein pathways impacted in children with Covid-19 who developed these serious symptoms,” McCafferty said. The findings were published in the journal, Nature Communications, on Monday, with researchers discovering 85 proteins specific to multisystem inflammatory syndrome and 52 linked to acute respiratory distress syndrome.
Knowing the specific proteins involved could improve diagnosis and lead to the development of targeted treatments for children suffering from severe Covid-19 cases. Currently, children affected are treated with intravenous immunoglobulin from donated blood, which reduces their chance of developing heart issues from one-in-four, to one-in-20. Children who do experience changes to their heart often see the issue resolve as they get older.
About 1.7% of children hospitalised with Covid-19 are admitted to intensive care. Most children who contract Covid-19 have mild or no symptoms.
The syndromes are so rare in Australia that researchers were sent blood samples taken from Covid-19 infected children with the syndromes receiving treatment at the Necker university hospital in France.
“France had the blood samples, while we had the proteomic testing capacity here in Melbourne,” McCafferty said. “This kind of collaboration is one of the silver linings to emerge from Covid-19.”
