K12.2 Cellulitis and abscess of mouth

The ICD-10-CM code for Cellulitis and abscess of mouth is K12.2 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

11: Diseases of the digestive system (K00-K95)

Section

K00-K14: Diseases of oral cavity and salivary glands (K00-K14)

Category K12

10 codes (8 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to K12.2:

• Uvulitis (acute) (catarrhal) (chronic) (membranous) (suppurative) (ulcerative)
• Ludwig's angina or disease
• Staphylitis (acute) (catarrhal) (chronic) (gangrenous) (membranous) (suppurative) (ulcerative)
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › sublingual
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › buccal cavity
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › submandibular (region) (space) (triangle)
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › mouth (floor)
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › palate (soft)

Inclusion Terms

• Cellulitis of mouth (floor)
• Submandibular abscess

U.S. Hospital Utilization

• An estimated 25,350 U.S. inpatient stays in 2023 included K12.2 among the documented diagnoses.
• 10,075 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Chapter 11 reserved for future expansion

11. Chapter 11: Diseases of the Digestive System (K00-K95) Reserved for future guideline expansion

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)