NEW YORK — MIS-C, or multisystem inflammatory syndrome, is an inflammatory condition in children which doctors believe may be a symptom of COVID-19. In some cases, MIS-C can lead to life-threatening problems in the heart. On a positive note, however, researchers from Columbia University report that children with MIS-C-related heart problems see these issues clear up within a matter of months.
Encompassing 45 hospitalized MIS-C patients with an average of nine years-old, this project is the first to assess cardiac and immune system-related outcomes in children with the condition.
“We’ve learned that COVID causes a spectrum of illness in children. Some are asymptomatic or mildly symptomatic and a small number of kids who develop MIS-C become critically ill, requiring admission to the ICU,” says first study author Kanwal M. Farooqi, MD, assistant professor of pediatrics at Columbia University Vagelos College of Physicians and Surgeons, in a university release. “It is a relief that this study shows that most of the severe heart and immunologic manifestations we saw in kids with MIS-C resolved rapidly.”
To be clear, MIS-C is quite rare. However, when it does occur it sparks widespread bodily inflammation. In most cases, kids who develop MIS-C don’t experience any COVID symptoms, but they do develop numerous symptoms in connection with MIS-C. Such symptoms include heart abnormalities, abdominal pain, skin rashes, and in some cases, extremely low blood pressure.
‘Scary’ complications for children with COVID
This subject hits particularly close to home for Columbia researchers. Pediatricians at New York-Presbyterian Morgan Stanley Children’s Hospital documented some of the first cases of MIS-C in spring 2020.
“It was both challenging and scary, because we didn’t know how these patients would do long term, especially in terms of cardiac and immunologic abnormalities, which were the most prominent issues at the time,” adds Dr. Farooqi, who is also a pediatric cardiologist at New York-Presbyterian Morgan Stanley Children’s Hospital.
The study finds most patients were in critical condition and required intensive care after entering the hospital. Moreover, close to 80 percent displayed some form of cardiac dysfunction, and nearly half showed moderate to severe cardiac abnormalities. Examples of such abnormalities include hampered ability of the heart to pump properly, coronary artery dilation, and leaking heart valves.
Meanwhile, two-thirds dealt with a temporary decrease in their white blood cell count. The vast majority had a big increase in inflammatory markers and over half showed elevated cardiac-specific markers consistent with heart injury.
To treat the excess inflammation, doctors gave these children steroids, with most receiving intravenous immunoglobulin and immunomodulators. One in three needed respirator support, although no one needed an external life-support machine. Finally, over half the group received treatment to help with low blood pressure.
“These kids were quite sick, but at our hospital, where we began using steroids and other treatments routinely for MIS-C, most of the patients responded rapidly and were discharged by about five days,” Dr. Farooqi explains.
Returning to normal after leaving the hospital
Immunologic abnormalities and markers for heart injury among these patients returned to normal within a few weeks time after the children left the hospital. By the time four months had passed, all of the coronary artery abnormalities and nearly all heart abnormalities had disappeared.
“It’s reassuring that our cardiac and immunologic outcomes were similar to those reported in a recent retrospective study of children hospitalized in the United Kingdom with MIS-C,” Dr. Farooqi says. “Nevertheless, given the absence of long-term data, we are recommending that children who had more than mild dysfunction on cardiac ultrasound should get a cardiac MRI at six months and see a pediatrician before being cleared for competitive sports.”
There aren’t as many new cases of MIS-C nowadays in comparison to last year’s coronavirus peak, but researchers say some new patients continue to require treatment.
“For parents, it’s reasonable to have children evaluated by a pediatrician or a cardiologist if they complain of nonspecific cardiac symptoms like chest pain or palpitations,” Dr. Farooqi concludes. “They can then be screened so that the need for further testing can be better assessed. Our team remains focused on the longer-term outcomes of these children with MIS-C and other potential long-term manifestations of SARS-CoV-2 infection.”
The findings appear in the journal Pediatrics.