I89.1 vs L03
I89.1 and L03 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 I89.1
acute lymphangitis (L03.-)
I89.1
Lymphangitis
Billable
- Chapter 9
- Diseases of the circulatory system
- Section
- I80-I89
Use when the record says
- Chronic lymphangitis
- Lymphangitis NOS
- Subacute lymphangitis
Indexed under
- Lymphangitis
- Gangrene, gangrenous › lymphangitis (connective tissue) (dropsical) (dry) (moist) (skin) (ulcer)
- Lymphangitis › chronic
- Lymphangitis › subacute
L03
Cellulitis and acute lymphangitis
Not billable
- Chapter 12
- Diseases of the skin and subcutaneous tissue
- Section
- L00-L08
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