K13.79 vs L98.5
K13.79 (Other lesions of oral mucosa) compared with L98.5 (Mucinosis of the skin), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. L98.5 carries an Excludes1 note covering K13.79: “focal oral mucinosis (K13.79)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| K13.79Other lesions of oral mucosa | L98.5Mucinosis of the skin | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | K00-K95 — Diseases of the Digestive System (K00-K95) | L00-L99 — Diseases of the Skin and Subcutaneous Tissue (L00-L99) |
| Definition | Other lesions of oral mucosa is a billable ICD-10-CM diagnosis code (K13.79). | Mucinosis of the skin is a billable ICD-10-CM diagnosis code (L98.5). |
| Includes | epithelial disturbances of tongue Focal oral mucinosis | Focal mucinosis Lichen myxedematosus Reticular erythematous mucinosis |
| Use additional code | code to identify: alcohol abuse and dependence (F10.-) exposure to environmental tobacco smoke (Z77.22) | — |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources