L93.2 vs M54.0
L93.2 and M54.0 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on M54.0
lupus panniculitis (L93.2)
L93.2
Other local lupus erythematosus
Billable
- Chapter 12
- Diseases of the skin and subcutaneous tissue
- Section
- L80-L99
Use when the record says
- Lupus erythematosus profundus
- Lupus panniculitis
Indexed under
- Lupus › panniculitis
- Panniculitis › lupus (nodular) (nonsuppurative)
- Lupus › erythematosus › profundus
- Lupus › erythematosus › specified NEC
M54.0
Panniculitis affecting regions of neck and back
Not billable
- Chapter 13
- Diseases of the musculoskeletal system and connective tissue
- Section
- M50-M54
These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027