By now, most of us have heard of MIS-C, the multisystem inflammatory syndrome that affects children who either have an active COVID-19 infection or had a COVID-19 infection a few weeks prior to developing MIS-C. The condition is rare—as of October 15, just over 1,000 cases were reported in 44 states, according to the CDC. In certain cases, MIS-C can be fatal.
But in early October, the CDC released a report warning physicians and medical personnel about a similar condition that can strike adults—Multisystem Inflammatory Syndrome in Adults, also known as MIS-A. One expert warned, “This needs to be in the forefront of every intensive care unit physician’s mind.”
MIS-A shares many symptoms of the dangerous syndrome found in kids. Here’s what we know so far.
Like in children, this inflammatory syndrome is a severe illness that targets multiple organ systems in the body and can increase inflammation.
The CDC reported on 27 cases and found “cardiovascular, gastrointestinal, dermatologic, and neurologic symptoms without severe respiratory illness” and elevated levels of markers of inflammation in each of the cases.
The symptoms included fever, gastrointestinal symptoms, cardiac symptoms, and rash. NBC reported on a patient who arrived in NYU Langone Health in New York City with “dusky-red circular patches on the palms of his hands and the soles of his feet,” chapped lips, and pink eyes.
The underlying cause of MIS-A is unknown, but health officials see a link with COVID-19.
As in the case of MIS-C, the underlying cause of MIS-A is not yet known. What is clear, so far, is that many of the patients in the CDC report tested negative for COVID-19, but positive for COVID-19 antibodies, suggesting a previous infection.
According to the report, 30% of the adults studied and 45% of 440 children with MIS-C reported to the CDC through the end of July had a negative COVID-19 test and a positive COVID-19 antibody result, which, taken together, suggests that “MIS-A and MIS-C might represent postinfectious processes.”
Shortness of breath or respiratory symptoms do not have to be present.
One of the hallmarks of a COVID-19 infection is shortness of breath or respiratory symptoms. In the case of MIS-A, respiratory symptoms are not a hallmark of the illness. Only eight of 16 patients had any reported respiratory symptoms before the onset of MIS-A, and those were largely mild.
In an interview with NBC News, Dr. Sapna Bamrah Morris, clinical lead for the Health Care Systems and Worker Safety Task Force, part of the CDC’s Covid-19 response, warned healthcare workers that, “Just because someone doesn’t present with respiratory symptoms as their primary manifestation does not mean that what they’re experiencing isn’t as a result of Covid-19.”
Age isn’t necessarily a factor in developing this syndrome.
Most patients who get severely ill with COVID-19 tend to be 65 or older, but that’s not the case when it comes to MIS-A. In the CDC report, 16 of the 27 patients studied were discussed in detail, and all of those were between the ages of 21 and 50.
The authors of the CDC report that “adult patients of all ages with current or previous SARS-CoV-2 infection can develop a hyperinflammatory syndrome resembling MIS-C.”
Racial and ethnic disparities exist.
According to the CDC, 75% of reported MIS-C cases have occurred in children who are Hispanic or Latino or Black.
A similar disparity exists in the case of MIS-A. The authors of the study noted that, “Long-standing health and social inequities have resulted in increased risk for infection and severe outcomes from COVID-19 in communities of color.” Of the 27 patients reported on by the CDC, all but one “belonged to racial or ethnic minority groups.”
There’s no proven treatment for MIS-A.
As of now, there is no proven treatment for MIS-A. Dr. Lilian Abbo, chief of infection prevention for Jackson Health System in Miami, told NBC News that “[w]e’re all just shooting blind.” A variety of treatments including steroids and drugs that impact the immune system are being tested.
In children, MIS-C is treated with intravenous immunoglobulin in some cases. That may be effective for adults, but the outcomes are as yet unknown. According to the CDC report, seven patients did receive this treatment.
In total, ten patients required intensive care, three required intubation or mechanical ventilation, and two tragically died.
MIS-A has probably been around since the beginning of the pandemic.
Even though we’re just hearing about it now, officials believe MIS-A has been around since the earliest days.
Dr. Hugh Cassiere, director of critical care services for Sandra Atlas Bass Heart Hospital at North Shore University Hospital, part of Northwell Health told NBC News that he’s convinced the syndrome has existed for a while and recalls that he was seeing patients that were coming in with organ failure, and yet testing negative for COVID-19. He suggests that they probably had this inflammatory syndrome, and “We didn’t have all the pieces to put together.”
When it comes to COVID-19, there’s still so much we don’t know. MIS-A is yet another mystery—from understanding why it affects some patients and not others to learning how to treat patients and discovering what the long term effects may be.
The good news is that this syndrome appears to be as rare in adults as it is in children. However, even though rare, MIS-A is yet another reason why it’s important for all of us to follow public health guidelines: social distance, wash hands, and wear a mask. Because we’re seven months into this pandemic, and though the pieces of this puzzle are coming together, the picture isn’t quite complete.
Information about COVID-19 is rapidly changing, and Scary Mommy is committed to providing the most recent data in our coverage. With news being updated so frequently, some of the information in this story may have changed after publication. For this reason, we are encouraging readers to use online resources from local public health departments, the Centers for Disease Control, and the World Health Organization to remain as informed as possible.