A large nationwide study found significant differences in the two main ways children became seriously ill with the coronavirus, findings that could help doctors and parents better recognize the conditions and understand more about the children at risk for each.
The study, published Wednesday in the journal JAMA, analyzed 1116 cases of young people treated in 66 hospitals in 31 states. Slightly more than half of the patients had acute Covid-19, the predominantly lung-related disease that afflicts most adults who become ill with the virus, while 539 patients had the inflammatory syndrome that broke out in some children weeks after they usually ‘ a mild initial infection.
The researchers found some similarities, but also significant differences in the symptoms and characteristics of the patients, ranging from infants to 20-year-olds and were admitted to hospital between March 15 and October 31 last year.
Young people with the syndrome, called Multisystem Inflammatory Syndrome in Children of MIS-C, were more likely to be between 6 and 12 years old, while more than 80 percent of patients with acute Covid-19 were younger than 6 or older. as 12.
More than two-thirds of the patients with one of the two conditions were black or Hispanic, which experts say probably reflects the socio-economic and other factors that have exposed some communities out of proportion to the virus.
“It is still shocking that the vast majority of patients are non-white and this applies to MIS-C and to acute Covid,” said Dr. Jean A. Ballweg, medical director of pediatric heart transplantation and advanced heart failure at Children’s Hospital & Medical said. Center in Omaha, which was not involved in the study. “There is clearly racial diversity there.”
Due to ambiguities, although Spanish young people are equally likely to be at risk for both conditions, it seems that black children are at greater risk of developing the inflammatory syndrome than the acute illness, Drs. Adrienne Randolph, the senior author of the study and a specialist in pediatric critical care at Boston Children’s Hospital.
One possible clue cited by the authors is that black children appear to have a higher frequency of heart disorders, and that they respond less to one of the standard treatments: with Kawasaki disease, a rare inflammatory syndrome in children, which has similarities with some aspects of MIS-C. intravenous immunoglobulin.
The researchers found that young people with the inflammatory syndrome were significantly more likely to have no underlying medical conditions than those with acute Covid. Yet, more than a third of patients with acute Covid had no medical condition. “It’s not as if healthy children here have been completely free before,” said Dr. Randolph said.
The study evaluated obesity separately from other underlying health conditions, and only in patients 2 years of age or older, and found that a slightly higher percentage of young people with acute Covid were obese.
Dr Srinivas Murthy, an associate professor of pediatrics at the University of British Columbia who was not involved in the study, said he was not convinced that the findings confirmed that healthy children were at higher risk for MIS-C. It could ‘mostly be a numbers game, with the proportion of children being infected and the proportion of healthy children out there, rather than saying that there is something immune in healthy children that puts them at an excessively higher risk,’ he said.
In general, the study’s documentation on the differences between the two conditions was useful, especially as it reflects a ‘fairly representative set of hospitals in the US’.
Young people with the inflammatory syndrome would probably need to be treated in intensive care units. Their symptoms were much more likely to involve gastrointestinal problems, inflammation and the skin and mucous membranes. It was also much more likely to have heart-related problems, although many of the acute Covid patients did not receive detailed heart assessments, the study noted.
About the same large percentage of patients with each condition – more than half – need respiratory support, with slightly less than a third of those requiring mechanical ventilation. Approximately the same small number of patients in each group died: 10 with MIS-C and eight with acute Covid-19.
The data do not reflect a recent increase in cases of inflammatory syndrome that followed an increase in overall Covid-19 infections during the winter holidays. Some hospitals reported that there were a greater number of seriously ill MIS-C patients in the current wave compared to previous waves.
“I would be fascinated to see a comparison from November 1 against this group, because I think we all felt that the children with MIS-C were even more ill recently,” said Dr. Ballweg said.
An optimistic sign from the study was that most severe heart problems in young people with the inflammatory syndrome improved to normal within thirty days. Dr. Randolph said the rest of the effects are still unknown. This is why one of her co-authors, dr. Jane Newburger, co-head of academic affairs in the cardiology department of Boston Children’s Hospital, is conducting a nationwide study leading children with the inflammatory syndrome for up to five years.
“We can not say for sure 100 percent that everything will be normal in the long run,” said Dr. Randolph said.