ICD-10 Code for Polymyositis
The default ICD-10-CM 2027 code for polymyositis (acute) (chronic) (hemorrhagic) is M33.20 – Polymyositis, organ involvement unspecified. More specific codes depend on the details documented, as listed in the official index (4 codes, 4 billable).
- Main code
M33.20– Polymyositis, organ involvement unspecified- Billable
- Yes
Index entries for Polymyositis
- with
- myopathy –
M33.22 - respiratory involvement –
M33.21 - skin involvement – see Dermatopolymyositis
- specified organ involvement NEC –
M33.29
- myopathy –
- ossificans (generalisata) (progressiva) – see Myositis, ossificans, progressiva
How to choose the right code
Start with the main term, then pick the indented subterm that matches the documentation (type, cause, site, laterality, episode of care). Always confirm the code in the tabular list: follow its Excludes1/Excludes2, “code first” and “use additional code” notes, and add a 7th character where required.
Source: CDC/NCHS ICD-10-CM FY2027 alphabetic index.