Excludes1 pair
M35.6 vs M79.3
M35.6 and M79.3 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.
The official note, declared on M79.3
relapsing [Weber-Christian] panniculitis (M35.6)
M35.6
Relapsing panniculitis [Weber-Christian]
Billable
- Chapter 13
- Diseases of the musculoskeletal system and connective tissue
- Section
- M30-M36
Indexed under
- Christian-Weber disease
- Weber-Christian disease
- Panniculitis › relapsing
M79.3
Panniculitis, unspecified
BillableUnspecified
- Chapter 13
- Diseases of the musculoskeletal system and connective tissue
- Section
- M70-M79
Indexed under
- Lipodermatosclerosis
- Panniculitis (nodular) (nonsuppurative)
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