Public schools are reopening in New York, although COVID-19 continues to spread, with new cases stabilizing at around 3,500 a day across the city and more contagious variants beginning to take hold.
Children are much less likely to catch the virus, but some who do can face serious consequences in the form of Multisystemic Inflammatory Syndrome in Children, or MIS-C. It is a condition in which different organs of the body can become inflamed, including the heart, lungs, brain and skin.
Now, a study by Northwell Health, the state’s largest health care system, points to a worrying outcome for positive COVID children and their kidneys. The researchers examined the medical records of 152 pediatric patients with COVID-19, admitted from March to August to four hospitals in the New York area. About one in 10 children with COVID-19 had acute kidney damage. The proportion doubled for those who also developed MIS-C. Severe renal dysfunction in children is typically very rare – on the order of one to two dozen cases per 100,000 children in developed countries.
Dr. Christine Sethna is an associate professor at the Feinstein Institutes for Medical Research at Northwell and one of the study’s co-authors. She spoke with David Furst of WNYC about her findings, how parents can detect MIS-C and when children can be eligible for the COVID-19 vaccines. The interview was slightly edited for clarity.
Can you briefly describe how MIS-C works? How long does it take to appear after a child contracts COVID? And how does it affect the body?
We don’t know the exact reason or mechanism, exactly how it happens. But we know that it is a post-viral syndrome, which means that we believe it is associated with a previous COVID infection. It usually appears six to eight weeks after infection.
What did your study find in terms of MIS-C and kidney injury? How often do you see this?
Thus, we studied the incidence of acute kidney injury, which is defined as the abrupt interruption of kidney function. And we examined 152 children admitted to our four Northwell health system hospitals, with acute infection by COVID-19 and MIS-C. And we found in the total cohort that we had that 11.2% had this acute kidney injury. Specifically, of the 55 children with MIS-C, the incidence was slightly higher; it was about 18.2%.
In general, children hospitalized with COVID and MIS-C are very rare and, in addition, it is still rare to have a kidney injury. But we want the public and the medical profession to know that this is a complication of COVID.
Fortunately, most children with acute kidney injury have been resolved. We had a couple who needed dialysis to help the kidney cleanse body waste. But the majority decided. Only two children left the hospital with some residual kidney problems.
The CDC says that New York City and New York State reported between 150 to 250 cases of MIS-C in childrenn. Should parents be concerned?
Still, in general, COVID-19 infection is occurring at much lower rates in children than in adults. And as for the proportion of COVID infection, the rate of MIS-C is even rarer. Therefore, there are more than 2,000 cases across the country. Therefore, it is extremely rare, but parents should still be aware.
Daily cases of MIS-C and COVID-19 in children in the USA (seven-day moving average), February 19, 2020 and February 21, 2021.
Age of reported cases of MIS-C in the United States, as of March 1, 2021
CDC
Race / ethnicity of reported cases of MIS-C in the United States, as of March 1, 2021
CDC
What should parents be aware of?
About six to eight weeks after an infection known as COVID, if you experience signs of vomiting, diarrhea, high fever, skin symptoms or lethargy, you should seek medical attention.
What is new about the trials of the COVID-19 vaccine in children? How long before they can get the vaccine and before they are vaccinated in large numbers?
Right. Therefore, the Pfizer vaccine is already approved for people over 16, but are not yet available in the state to be vaccinated, unless you currently have a health problem. But when that happens, the Pfizer vaccine will be eligible for 16 years or more.
Both Pfizer and Moderna have completed enrollment in their clinical trials for children aged 12 to 15 and up to 18 for Moderna. And therefore, we expect these results probably in late spring, early summer.
So, at best, I would say it’s summer for the 12-15 year olds until autumn for them. The next stage is for children under the age of 12. They have not yet started to enroll in this group. This will be much later, probably at the end of the year or even in the beginning of 2022.