M35.81 — Multisystem inflammatory syndrome
M35.81 is a billable, specific ICD-10-CM code for multisystem inflammatory syndrome. It is valid for submission on a claim.
Code first
The underlying condition must be sequenced before this code.
- , if applicable, COVID-19 (U07.1)
Use additional code
Add a secondary code to capture the detail described below.
Code also
Both codes may be needed to describe the encounter fully. Sequencing depends on the reason for the visit.
- any associated complications such as:
- acute hepatic failure (K72.0-)
- acute kidney failure (N17.-)
- acute myocarditis (I40.-)
- acute respiratory distress syndrome (J80)
- cardiac arrhythmia (I47-I49.-)
- pneumonia due to COVID-19 (J12.82)
- severe sepsis (R65.2-)
- viral cardiomyopathy (B33.24)
- viral pericarditis (B33.23)
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- MIS-A
- MIS-C
- Multisystem inflammatory syndrome in adults
- Multisystem inflammatory syndrome in children
- Pediatric inflammatory multisystem syndrome
- PIMS
Risk adjustment
M35.81 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:
- HCC 2 Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock0.500 RAF
Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.
Medicare coverage
M35.81 is named in 15 Medicare coverage policies — 9 listing it as supporting medical necessity, and 6 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A58865Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
- A58893Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
- A59374Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
- A59434Billing and Coding: Amniotic and Placental-Derived Product Injections and/or Applications for Musculoskeletal Indications, Non-Woundnot covered
How M35.81 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to M35.81.
- MIS-A
- MIS-C
- Multisystem inflammatory syndrome(in adult) (in children)
- Pediatric inflammatory multisystem syndrome
- PIMS
- Syndrome›multisystem inflammatory(in adults) (in children)
- Syndrome›pediatric inflammatory multisystem
Related codes at this level
Codes that share M35.8. If M35.81 is not quite right, the correct code is usually one of these.
Questions about M35.81
- Is M35.81 a billable ICD-10-CM code?
- Yes. M35.81 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does M35.81 sit in the tabular list?
- Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Systemic connective tissue disorders (M30-M36).