K13.0 vs L59
K13.0 and L59 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 K13.0
cheilitis due to radiation-related disorders (L55-L59)
K13.0
Diseases of lips
Billable
- Chapter 11
- Diseases of the digestive system
- Section
- K00-K14
Use when the record says
- Abscess of lips
- Angular cheilitis
- Cellulitis of lips
- Cheilitis NOS
- Cheilodynia
- Cheilosis
- Exfoliative cheilitis
- Fistula of lips
Indexed under
- Angulus infectiosus (lips)
- Baelz's disease (cheilitis glandularis apostematosa)
- Cheilitis (acute) (angular) (catarrhal) (chronic) (exfoliative) (gangrenous) (glandular) (infectional) (suppurative) (ulcerative) (vesicular)
- Cheilodynia
- Cheilosis (angular)
L59
Other disorders of skin and subcutaneous tissue related to radiation
Not billable
- Chapter 12
- Diseases of the skin and subcutaneous tissue
- Section
- L55-L59
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