As many states move toward reopening and parents begin to hope that summer camp may be a possibility, news of a rare, but serious, inflammatory syndrome in kids is raising alarm.
This past week, Yale New Haven Children’s Hospital (YNHCH) diagnosed Connecticut’s first cases of a condition called pediatric multisystem inflammatory syndrome (PMIS), and more have since been reported at Connecticut Children’s Medical Center in Hartford. It can affect infants through teenagers, with the initial patients at YNHCH ranging from ages 13 to 18.
Medical experts believe that the syndrome, which can cause dangerous levels of inflammation throughout the entire body, is related to COVID-19, but they don’t know for sure. Most patients with PMIS (which is also known as multisystem inflammatory syndrome in children or MIS-C), have tested positive for the new coronavirus or have antibodies to it, which means they were infected by it—even if they didn’t show symptoms.
“This seems to be a new manifestation associated with COVID-19. There is much we still don’t know, but it appears to occur in children after they have gotten better from COVID, and it has a lot of similarities to other diseases we see in pediatrics, including Kawasaki disease and toxic shock syndrome,” says Marietta Vázquez, MD, a Yale Medicine pediatric infectious disease specialist. “Overall, our patients are doing well, and this is not a cause for panic—but a message to be vigilant. If you have a child with a high fever for no other apparent reason, and other symptoms such as red eyes, belly pain, a prickly heat rash all over the body, muscle aches, vomiting, or diarrhea, call your pediatrician.”
Clifford Bogue, MD, chair of Yale Medicine Pediatrics and chief medical officer of YNHCH, adds that early treatment is important.
“Based on our experience with this and other conditions in which there is a severe inflammatory response that could lead to organ injury or failure, we want to identify and treat patients as soon as we can,” Dr. Bogue says. “Parents should be aware of symptoms of this syndrome, even if there is no history of COVID—because many kids have COVID with no symptoms. This can also appear weeks after a COVID infection.”
The Centers for Disease Control and Prevention (CDC), Dr. Bogue adds, is working on developing a case definition of the syndrome for tracking and reporting purposes.
To treat PMIS, Dr. Bogue says Yale doctors have been using antibiotics, high-dose steroids, intravenous immunoglobin (blood plasma that contains antibodies), and a biologic medication commonly used for rheumatoid arthritis and other inflammatory diseases. “The therapies are all geared toward tamping down the body’s inflammatory response,” Dr. Bogue explains.
Controlling the inflammatory reaction is vital, Dr. Vázquez says, because as patients get sicker, their hearts begin to race and blood pressure decreases, which can lead the body to go into shock—a potentially fatal condition if not treated quickly.
“But the prognosis for our patients is good. Their illnesses were severe and quick, but they have responded well to treatment,” she says.
Initial U.S. cases of PMIS appeared in New York
The first U.S. cases of PMIS emerged in New York in early May, about a month after a surge of COVID-19 infections in the region. Three children have died in New York, where the majority of the 100-plus cases detected so far have been located. A handful of other states have also reported cases. There have been cases of PMIS in Europe, including England, where a 15-year-old died from it.
Given how Connecticut’s coronavirus trajectory has followed that of New York, though on a smaller scale, Dr. Bogue says he expects the state will have more PMIS cases. “Based on the experience of New York, it seems those cases popped up two to four weeks after they hit their peak of infections, and if we apply the same logic, our experience may be similar,” he says.
Fortunately, Dr. Bogue says, physicians now have a heightened suspicion to look for the syndrome. “We have put together a team of infectious disease specialists, rheumatologists, cardiologists, and critical care doctors who are aggressive about treating this and will be following up with patients,” he adds.
COVID-19 remains uncommon in children
Not only is PMIS extremely rare, COVID-19 remains uncommon in children. In the U.S., only 2% of confirmed coronavirus cases have been in children under age 18. According to Dr. Bogue, YNHCH has hospitalized 20 children with COVID-19, none of whom died. A few of the children were admitted to the hospital for unrelated surgeries and, though asymptomatic, were confirmed to have the virus when they were tested—as is routine for all patients.
For the most part, the common presentation of COVID-19 as a respiratory disease has been less severe in children, Dr. Vázquez says.
“We don’t know why children get less severe disease with COVID, but it probably is because they are younger and healthier. With other respiratory infections, like pneumonia and influenza, it is mostly the elderly who get very sick,” she says. “And now when we look at this new syndrome, it is thought to occur as a child’s body is making protective antibodies against COVID. Children’s immune systems are very robust and they respond and make a lot of antibodies, so maybe that is why we see this antibody-linked manifestation.”
PMIS resembles other inflammatory diseases
PMIS has certain characteristics in common with Kawasaki disease, which is rare and typically affects children age 5 and younger, though it can occur in older kids. Symptoms include fever, rash, swelling of the hands and feet, redness of the eyes, swollen lymph nodes in the neck, and irritation of the mouth, lips, and throat.
“We don’t know what causes Kawasaki, but it can particularly affect the heart muscle and lead to swelling and problems with the arteries that feed the muscle of the heart,” Dr. Vázquez says.
Kawasaki disease is the leading cause of acquired heart disease in the U.S. and carries the risk of complications including coronary artery aneurysms. Proper treatment greatly reduces the risk of these problems.
“With Kawasaki, the biggest complication over time is the development of aneurysms, which can show up in the acute phase or much later,” Dr. Bogue says. “We don’t know yet if that will be the case with this syndrome, but we are making plans to do repeat echocardiograms and continue to evaluate their hearts.”
Don’t fear seeking medical help
Dr. Vázquez stresses that parents should not be afraid to bring their children in for medical care if they suspect PIMS, any other problem, and also routine preventive care.
“Our pediatric offices have never closed. And for this new syndrome, the message to parents is to be aware that this exists and to not fear coming into the hospital if their child needs it,” she says. “We have treatments that work well, and everyone is taking great care to prevent spreading contagions.”
Beth Emerson, MD, medical director of YNHCH Emergency Department, echoes that sentiment.
“The main thing for parents to know is that this inflammatory syndrome is different from a COVID respiratory infection, and it has been seen mostly after a known or suspected infection,” she says. “Families with concerns should contact their pediatrician. If they are worried that the child is having trouble breathing, is sleepier than usual, is having severe pain, or there are other concerns that the family does not think should wait, our emergency departments are ready to provide care.”