ICD-10-CM 2027
ICD-10 code for Multisystem inflammatory syndrome
From the official ICD-10-CM alphabetic index entry “Multisystem inflammatory syndrome (in adult) (in children)”. Page updated September 29, 2026.
About coding Multisystem inflammatory syndrome
The ICD-10-CM code for Multisystem inflammatory syndrome is M35.81 (Multisystem inflammatory syndrome).
Within M35.8 (other specified systemic involvement of connective tissue), M35.81 is specifically for Multisystem inflammatory syndrome. Related codes cover other specified systemic involvement of connective tissue (M35.89).
Code first: , if applicable, COVID-19 (U07.1).
Use an additional code, if applicable, for: exposure to COVID-19 or SARS-CoV-2 infection (Z20.822), personal history of COVID-19 (Z86.16) and post COVID-19 condition (U09.9).
Common questions about Multisystem inflammatory syndrome ICD-10 codes
What is the ICD-10 code for Multisystem inflammatory syndrome?
- M35.81 — Multisystem inflammatory syndrome.
Is M35.81 billable?
- Yes. M35.81 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can M35.81 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict M35.81 as a principal diagnosis.
Is M35.81 a CC or MCC?
- M35.81 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.