Multisystem Inflammatory Syndrome in Adults (MIS-A) Case Definition Information for Healthcare Providers
Case Definition for MIS-A
A patient aged ≥21 years hospitalized for ≥24 hours, or with an illness resulting in death, who meets the following clinical and laboratory criteria. The patient should not have a more likely alternative diagnosis for the illness (e.g., bacterial sepsis, exacerbation of a chronic medical condition).
- Clinical Criteria
Subjective fever or documented fever (≥38.0 C) for ≥24 hours prior to hospitalization or within the first THREE days of hospitalization* and at least THREE of the following clinical criteria occurring prior to hospitalization or within the first THREE days of hospitalization*. At least ONE must be a primary clinical criterion.
- Primary clinical criteria
- Severe cardiac illness Includes myocarditis, pericarditis, coronary artery dilatation/aneurysm, or new-onset right or left ventricular dysfunction (LVEF<50%), 2nd/3rd degree A-V block, or ventricular tachycardia. (Note: cardiac arrest alone does not meet this criterion)
- Rash AND non-purulent conjunctivitis
- Secondary clinical criteria
- New-onset neurologic signs and symptoms Includes encephalopathy in a patient without prior cognitive impairment, seizures, meningeal signs, or peripheral neuropathy (including Guillain-Barré syndrome)
- Shock or hypotension not attributable to medical therapy (e.g., sedation, renal replacement therapy)
- Abdominal pain, vomiting, or diarrhea
- Thrombocytopenia (platelet count <150,000/ microliter)
- Primary clinical criteria
- Laboratory evidence
The presence of laboratory evidence of inflammation AND SARS-CoV-2 infection.
- Elevated levels of at least TWO of the following: C-reactive protein, ferritin, IL-6, erythrocyte sedimentation rate, procalcitonin
- A positive SARS-CoV-2 test for current or recent infection by RT-PCR, serology, or antigen detection
NOTE: *These criteria must be met by the end of hospital day 3, where the date of hospital admission is hospital day 0.
New ICD-10-CM Diagnosis Code for MIS: M35.81external icon
- Applicable to:
- Multisystem inflammatory syndrome in adults
- Multisystem inflammatory syndrome in children
- Pediatric inflammatory multisystem syndrome
- Use additional code, if applicable, for:
- Code first, if applicable, COVID-19 (U07.1external icon)
- Code also any associated complications
Related Research and More Information
- Case Series of Multisystem Inflammatory Syndrome in Adults Associated with SARS-CoV-2 Infection — United Kingdom and United States, March–August 2020
- Clinical Characteristics of Multisystem Inflammatory Syndrome in Adults: A Systematic Review | Global Health | JAMA Network Open | JAMA Networkexternal icon