For more information on COVID-19 in children, see our previous article written April 27, 2020.
From the beginning of the COVID-19 pandemic, one seemingly bright spot has been that children appeared to be largely unaffected. Unfortunately, however, the emergence of a new and mysterious condition, called Pediatric Multi-system Inflammatory Syndrome (also known as PIMS, PMIS, and/or MIS-C), is now thought to be linked to COVID-19 infection in children. Although this new syndrome is believed to be rare, its presence marks a critical turning point in our widely held understanding of COVID-19 and its impact on kids and teenagers.
As the coming weeks and months unfold, our knowledge of this condition will continue to develop but as of now, there are still many unknowns. As the resident pediatrician at Parsley Health, I’ll help guide you through the newest updates regarding SARS-CoV-2 and its effects on kids and what we currently do and do not know about this newly recognized, and potentially harmful complication.
What is Pediatric Multi-system Inflammatory Syndrome?
Pediatric Multi-system Inflammatory Syndrome (PIMS) seems to affect children who have been infected with the novel coronavirus, recovered from the infection, and later develop a significant immune response from their previous exposure. This response causes widespread systemic inflammation of many organs in the child’s body, including the heart. Children who have PIMS generally did not have hallmark symptoms when they were infected with COVID-19, such as dry cough or shortness of breath, and many were completely asymptomatic.
A child with PIMS commonly presents with an unrelenting fever, skin rash, conjunctivitis (pink eye), general pain and swelling in their extremities, and significant abdominal pain which may or may not accompany diarrhea or vomiting. They also appear to have symptoms consistent with toxic shock including very low blood pressure and an inability to effectively circulate oxygen and nutrients through the blood. A key theme is that children with PIMS look visibly very sick—with notable inflammation and redness on their skin, eyes, and limbs. Upon the onset of PIMS symptoms, a child may or may not test positive for an active infection of COVID-19, but antibody testing is likely to reveal they were previously infected. PIMS is more likely to occur 4-6 weeks following a COVID-19 exposure.
Some children with post-COVID PIMS present very similarly to another condition called Kawasaki disease, a post-viral pediatric phenomenon that involves inflammation in the walls of some blood vessels, commonly including the arteries that supply the heart with blood. Kawasaki is an extremely rare but well-known complication of viral illnesses that is treated successfully in most cases, but does require follow up with a cardiologist and frequent echocardiograms given its potential cardiac consequences.
While the current syndrome PIMS shares features of Kawasaki, it appears to be more invasive and also shares clinical similarities with another serious illness, Toxic Shock Syndrome—a rare, life-threatening complication of certain bacterial infections.
What are the symptoms of Pediatric Multi-system Inflammatory Syndrome?
While PIMS is currently believed to be rare, it’s important to look out for classic symptoms that might present in your child, especially if you suspect that they’ve previously had or were exposed to someone who was infected with SARS-CoV-2.
If you notice any of the following symptoms in your child, we recommend calling their pediatrician:
- Persistent fever greater than 100.4 degrees Fahrenheit
- Abdominal pain which can but may not involve diarrhea, or vomiting
- Visible rash or changes in skin color
- Trouble breathing
- Severe headache
- Swollen hands and feet, which might also be red
- Bright red eyes
- Red and cracked lips or tongue
- Racing heart or chest pain
- Joint pain or swelling
- Apparent lethargy, irritability, or confusion
- Decreased urination
How many children have been affected by Pediatric Multi-system Inflammatory Syndrome?
The first report was cited in London in April when during a 10-day period eight children between the ages of 4 and 14 years old presented with an inflammatory syndrome—most of whom had tested positive for or had antibodies to the novel coronavirus.
Since the original cases that popped up in Europe in April, the U.S. cases have mainly been in East Coast cities, particularly in the areas hardest hit by the pandemic, with some cases in the Midwest and South. In the first weeks of May 2020, the Department of Health reported over 100 cases of children exhibiting symptoms consistent with PIMS in New York state alone, the majority of which were in the country’s epicenter of New York City. Of the confirmed pediatric cases in the city, less than half of the children tested positive for COVID-19. However, most who tested negative were found to have antibodies to the virus—indicating previous exposure to the novel coronavirus.
Diagnosing and treating Pediatric Multi-system Inflammatory Syndrome
PIMS is diagnosed by assessing inflammation levels through laboratory analysis of elevated biomarkers in the blood such as C-reactive protein (CRP) and altered white blood cell counts. Doctors will also look for any organ dysfunction through cardiac, respiratory, renal, gastrointestinaI, or neurological distress, with at least two organs needing to be involved to meet the criteria for diagnosis.
To confirm a PIMS diagnosis, other potential causes of the symptoms such as a microbial condition or bacterial sepsis must be ruled out. The child will also be tested for current or recent SARS-CoV-2 infection via nasal swab, antigen, and/or antibody testing. Separately, a serious concern with this syndrome is inflammation of the heart so early imaging can help to detect any cardiac involvement and play an important role in preventing potentially fatal outcomes such as cardiac aneurysms.
The reassuring news is that PIMS can be successfully treated in most children. The current recommendations for treatment include use of immediate broad spectrum intravenous antibiotics such as ceftriaxone and clindamycin. That treatment will be followed by potential administration of aspirin, steroids, and immunoglobulin therapy if needed. Typical hospital stays for children with PIMS may last two to four days. For more serious cases, a child might need supportive care for shock if there are concerns regarding cardiac involvement as well as the administration of immunosuppressive drugs such as IL-1 and IL-6 antagonists and other immune modulators.
In terms of follow up, similar to Kawasaki disease, it’s recommended that a child receives an echocardiogram—an ultrasound of the heart—every 3 weeks regardless of if they had cardiac involvement at the beginning, as well as regular follow-up appointments with a cardiologist. Most children seem to do well and fully recover with supportive care.
What this means for parents of kids and teenagers
By no means is every child with COVID-19 likely to experience this inflammatory complication. Children continue to do incredibly well with SARS-CoV-2 as mentioned in our previous article on COVID-19 and pediatric outcomes.
However, given the increasing incidence of PIMS, it does change the paradigm of kids being totally protected, and will likely affect guidelines of children going back to school, camp, and other group recreational activities.
During this time, it is even more crucial for parents to stay in close contact with their personal healthcare providers and their child’s pediatrician should symptoms of COVID-19 or PIMS arise.
At Parsley Health, we are actively staying in touch with our members—both children and adults—while supporting them in navigating the onset of any symptoms. Our care team is here to support our members through messaging seven days per week and online visits as needed. We are committed to helping guide our members and broader community through our continued understanding of COVID-19 especially as this disease and its implications continue to evolve.