Read next
Researchers identify attributes that may differentiate MIS-C from COVID-19
Click Here to Manage Email Alerts
A study involving more than 1,000 patients identified cardiac involvement, age and race as attributes that could differentiate multisystem inflammatory syndrome in children from severe COVID-19, researchers reported in JAMA.
CDC epidemiologist Leora R. Feldstein, PhD, and colleagues conducted a case series that included 1,116 patients aged younger than 21 years from the Overcoming COVID-19 network who were hospitalized in 31 states from March 15 through Oct. 31 — 539 (48%) with MIS-C and 577 (52%) with acute COVID-19.
Of those with MIS-C, 52% had a positive reverse transcriptase PCR test for SARS-CoV-2, 45% were positive only for antibodies, 31% were positive for both and 19% did not have an antibody test performed, Feldstein and colleagues reported.
Among presenting symptoms and signs, they found that only mucocutaneous findings differed in its prevalence, appearing in 66.8% (95% CI, 63%-71%) of patients with MIS-C vs. 10.2% (95% CI, 8%-13%) of patients with COVID-19.
Cardiac involvement was more common among participants with MIS-C (66.7%; 95% CI, 63%-71%) vs. COVID-19 (11.8%; 95% CI, 9%-15%). In both cohorts, 80% of patients had severe respiratory involvement.
Additionally, patients diagnosed with MIS-C were more likely to be aged 6 to 12 years (40.8% vs 19.4%; risk difference [RD] = 21.4% [95% CI, 16.1%-26.7%]); be Black (32.3% vs. 21.5%; RD = 10.8% [95% CI, 5.6%-16%]) and have no underlying conditions (69% vs 37.9%; RD = 31.1% [95% CI, 25.5%-36.6%]).
Following an adjustment for covariates, the authors reported that the risk for MIS-C was higher for those aged 6 to 12 years compared with those aged 0 to 5 years (aRR, 1.51; 95% CI, 1.33-1.72), as well as patients who were Black compared with those who were white (adjusted RR, 1.43; 95% CI, 1.17-1.76).
Additionally, patients with MIS-C were more likely to have cardiorespiratory involvement compared with those with COVID-19 (56% vs 8.8%; RD = 47.2; 95% CI, 42.4%-52%), cardiovascular without respiratory involvement (10.6% vs 2.9%; RD = 7.7%; 95% CI, 4.7%-10.6%), and mucocutaneous without cardiorespiratory involvement (7.1% vs 2.3%; RD = 4.8%; 95% CI, 2.3%-7.3%).
An MIS-C diagnosis also was more likely in patients with cardiorespiratory involvement compared with patients with respiratory involvement alone (aRR = 2.99; 95% CI, 2.55-3.5) and mucocutaneous without cardiorespiratory involvement (aRR = 2.29; 95% CI, 1.84-2.85).
Perspective
Back to TopDavid Cennimo, MD
This report is very interesting and timely and helps the treating clinician who is grappling with the diagnostic uncertainty of if the child has severe COVID-19 or MIS-C.
The authors looked at data from March to October 2020 from a study network representing 31 states; so, this study is well represented. The children were considered to have MIS-C if they met the CDC criteria — fever, laboratory evidence of inflammation, severe illness involving at least two organ systems, current or recent exposure or positive SARS-CoV-2 testing. Patients were considered to have severe COVID-19 if they had evidence of current infection and severe organ involvement of at least one organ system.
The network reported 1,314 children (aged younger than 21 years) hospitalized with COVID-19 during the time period. A total of 198 were excluded because they did not meet criteria for severe illness. In the final analysis, of the 1,116 remaining cases, 48% were classified as MIS-C and 52% as severe COVID-19.
This fits with many of our "real-world" experiences of seeing both manifestations of the infection. The presenting signs and symptoms were similar, with the exception of significantly more mucocutaneous findings in MIS-C. This is unsurprising because MIS-C was initially felt to strongly resemble Kawasaki disease for the same reasons. Both groups had significant respiratory involvement, but cardiac involvement was much more common (66.7% vs. 11.8%) in patients with MIS-C.
Most children with decreased ejection fraction did normalize within 1 to 2 weeks after their MIS-C diagnosis. Children suffering from MIS-C also demonstrated labs consistent with a higher level of inflammation. The risk for MIS-C diagnosis was highest in children 6 to 12 years old and in non-Hispanic Blacks.
All told, I think this study helps delineate the clinical patterns distinguishing severe COVID-19 from MIS-C and gives us some comfort that most patients suffering from MIS-C do well in the long run.
Read more about
Click Here to Manage Email Alerts
