When the coronavirus disease 2019 (COVID-19) outbreak began, the one silver lining was that the virus seemed to be less common in children, who mostly had mild or even no symptoms if infected. While this is still true, health experts now warn that children can contract a rare condition linked to COVID-19 called pediatric multisystem inflammatory syndrome, or PMIS.
We’ve answered some common questions parents may have about PMIS with the help of UNC Health pediatric rheumatologist and allergist/immunologist Eveline Wu, MD.
What is PMIS?
PMIS is a condition that causes inflammation of the blood vessels and multiple organs in the body, including the heart, kidneys, skin and gastrointestinal organs. Also called multisystem inflammatory syndrome in children (MIS-C), it is potentially life-threatening and requires immediate medical attention.
Doctors don’t yet understand the link between COVID-19 and PMIS. One theory is that PMIS results when a child’s immune system goes into overdrive trying to fight the COVID-19 virus. This aggressive immune response can threaten organ function.
What are the symptoms of PMIS?
Symptoms of PMIS include a prolonged fever, meaning a temperature of 100.4 degrees or greater that lasts several days, with other symptoms including:
- Stomach pain
- Swollen hands and feet that might also be red
“Parents need to be educated about these symptoms and should call their child’s doctor right away if their child has a persistent fever with any of these other symptoms,” Dr. Wu says.
Your child’s doctor will ask about your child’s symptoms and use that information to recommend next steps. If your child is severely ill with confusion, trouble breathing, chest pain or pressure, or bluish face or lips, go to the nearest emergency department or call 911 immediately.
What is the connection between PMIS and Kawasaki disease?
Children with PMIS can have symptoms similar to those of Kawasaki disease, a condition that usually affects children ages 2 to 4, causing inflammation in the blood vessels, Dr. Wu says. Doctors do not know how children develop Kawasaki disease, but it is not thought to be contagious.
“Children with Kawasaki disease typically present with persistent fever, red eyes, changes to the lips and mouth, swelling in the lymph nodes or glands of the neck, rash, and swelling in their hands and feet,” Dr. Wu says.
Like PMIS, one of the most serious complications of Kawasaki disease is inflammation of the coronary arteries of the heart.
While many children with PMIS have had symptoms very similar to those of Kawasaki disease, not all have. Other children with PMIS have had symptoms that are similar to those of another inflammatory condition called toxic shock syndrome, including headache, vomiting, confusion and diarrhea.
“Toxic shock syndrome is a condition that’s caused by certain bacteria and the toxins that they produce that cause rapid drops in blood pressure,” Dr. Wu says.
Toxic shock syndrome can lead to organ failure, including the heart, lungs and liver.
In addition, children with PMIS often have gastrointestinal symptoms, such as abdominal pain, vomiting and diarrhea, which are not usually symptoms of Kawasaki disease.
“Children with PMIS are presenting with any combination of these symptoms,” Dr. Wu says.
If my child has PMIS, does that mean he or she had COVID-19?
PMIS is thought to result from the body’s immune response to the virus and is not a direct effect of an acute, active COVID-19 infection. Most children with PMIS have tested positive for COVID-19, and there is a strong connection between PMIS and COVID-19 in terms of timing and geographical association.
Where there has been a higher burden of COVID-19 cases, such as in New York, “there’s been a higher cluster of PMIS,” Dr. Wu says.
But keep in mind, most pediatric patients who have had COVID-19 haven’t developed PMIS.
Can I prevent PMIS?
Who is most at risk for PMIS?
Health officials do not know yet who is most at risk for PMIS, Dr. Wu says. If your child has an underlying medical condition such as chronic lung disease, he or she may be at higher risk of complications from COVID-19, but it remains unclear whether this is true for PMIS.
“We’re still trying to understand why some children get PMIS and others don’t,” Dr. Wu says. “And we’re learning something new all the time.”