Excellent supportive care is essential in all cases; antiinflammatory and immunomodulatory therapies have been used in severely ill patients (particularly those who fulfill criteria for Kawasaki disease) r4r5r6r7r25r26
- Specific guidance for treatment of shock and hypoxemia in MIS-C is lacking but includes oxygen administration (including mechanical ventilation, if necessary), cautious fluid resuscitation (preferably guided by assessment of likely responsiveness), and vasopressor support, using appropriate protocols for shock (ie, cardiogenicr30 versus vasodilatory/distributiver31) d6
- Extracorporeal membrane oxygenation has been used in some patients
For patients who meet Kawasaki disease criteria, consider treating with IV immunoglobulin and aspirin; Kawasaki disease guidelinesr11 encourage treatment as early as the diagnosis is established and preferably within 10 days of illness onset r4r28d1
- Most patients respond promptly to a single dose of IV immunoglobulin, but as in Kawasaki disease, resistance occurs in some patients. A second dose of IV immunoglobulin, with or without methylprednisolone, is often effective r14
- Patients with aneurysms and z scores of 10 or higher, documented thrombosis, or ejection fraction less than 35% are given therapeutic anticoagulation in addition to aspirin r25
For patients who meet criteria for toxic shock, consider using IV immunoglobulin r4d3
IV immunoglobulin has also been used successfully in children who do not meet criteria for Kawasaki disease or toxic shock but who do have severe manifestations of MIS-C, including myocarditis, shock, persistent fever, and elevated inflammatory markers or other clinical indicators of severe illness. Consider such therapy for critically ill patients even before the evaluation is completer25r7r9r21r32d7
Glucocorticoids are commonly used in conjunction with IV immunoglobulin or as follow-up to it if response is less than desired r25
Other treatments that have been associated with apparently successful outcomes include infliximab, anakinra, and tocilizumab, but data are scant and noncomparative r2r7r8r9r10
For patients in whom sepsis caused by other pathogens has not been ruled out, begin empiric antibiotics, which can be de-escalated if indicated based on results of microbiologic studies r5d4
As MIS-C appears to be a postinfectious inflammatory response, antiviral therapy has not generally been initiated; nevertheless, use of infection control precautions appropriate for COVID-19 is recommended by some authorities r4
- IV immunoglobulin
- Immune Globulin (Human) Solution for injection; Infants, Children, and Adolescents: Available data are limited, and efficacy has not been established. 1,000 to 2,000 mg/kg IV as a single dose in combination with aspirin and/or methylprednisolone has been reported and is being used in some institutional protocols. Depending on the severity of illness, additional doses have been administered.
- Aspirin Oral tablet; Infants, Children, and Adolescents: Available data are limited, and efficacy has not been established. Doses varying from 3 to 5 mg/kg/day PO (low dose) to 30 to 100 mg/kg/day PO (moderate to high dose) have been reported and are being used in combination with IVIG with or without methylprednisolone.
- Methylprednisolone Sodium Succinate Solution for injection; Infants, Children, and Adolescents: Available data are limited, and efficacy has not been established. 2 to 30 mg/kg/day IV has been reported, depending on the severity of illness, and is being used in combination with IVIG with or without aspirin. A 3-week at-home taper has been recommended.