On May 14, 2020, the CDC issued an official Heath Advisory dealing with COVID-19-associated Multisystem Inflammatory Syndrome in Children (MIS-C). This advisory was based on the rapid emergence of pediatric cases of severe inflammatory syndrome with Kawasaki disease-like manifestations. The first U.S. cases were reported in early May from our “epicenter” in New York City. Over the ensuring days, 102 cases were reported to the New York State Department of Health.
A cohort comparison study, from hard-hit ltaly, evaluated Kawasaki-like disease cases diagnosed at one center over two time periods: January 1, 2015—February 17, 2020 and February 18, 2020—April 20, 2020. Compared to the first, the monthly incidence was 30-fold greater in the second cohort. In addition, the average age of cases was greater (7.5 years vs. 3.0 years), and more children had Kawasaki disease shock syndrome, cardiac involvement, and macrophage activation syndrome. Most of the children in the second cohort (80%) were positive for SARS-CoV-2 IgG or IgM.
The CDC has established the following case definition for MIS-C.
Case Definition for Multisystem Inflammatory Syndrome in Children (MIS-C)
- An individual aged <21 years presenting with fever, laboratory evidence of inflammation, and evidence of clinically severe illness requiring hospitalization, with multisystem (>2) organ involvement (cardiac, renal, respiratory, hematologic, gastrointestinal, dermatologic or neurological); AND
- No alternative plausible diagnoses; AND
- Positive for current or recent SARS-CoV-2 infection by RT-PCR, serology, or antigen test; or COVID-19 exposure within the 4 weeks prior to the onset of symptoms.
Currently MIS has been noted in children. It is unknown if adults will also present with these or similar findings. Recognition of cases meeting this definition needs to be coupled with rapid reporting to the appropriate public health agency.