K12.2Cellulitis and abscess of mouth

K12.2 is the ICD-10-CM diagnosis code for cellulitis and abscess of mouth. It belongs to category K12 (stomatitis and related lesions), block K00-K14 (diseases of oral cavity and salivary glands) and chapter 11 (diseases of the digestive system). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within K12 (stomatitis and related lesions), K12.2 is specifically for cellulitis and abscess of mouth. Related codes cover recurrent oral aphthae (K12.0), other forms of stomatitis (K12.1) and oral mucositis (ulcerative) (K12.3).

The conditions in its Excludes2 note aren't part of K12.2, but may be coded alongside it if the patient has both: abscess of salivary gland (K11.3), abscess of tongue (K14.0), periapical abscess (K04.6-K04.7), periodontal abscess (K05.21) and 1 more.

Use an additional code to identify: alcohol abuse and dependence (F10.-), exposure to environmental tobacco smoke (Z77.22), exposure to tobacco smoke in the perinatal period (P96.81), history of tobacco dependence (Z87.891), occupational exposure to environmental tobacco smoke (Z57.31) and 2 more.

As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 011 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with MCC, relative weight 5.6154), DRG 012 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with CC, relative weight 4.381), DRG 013 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy without CC/MCC, relative weight 2.7307), DRG 157 (Dental and Oral Diseases with MCC, relative weight 1.809), DRG 158 (Dental and Oral Diseases with CC, relative weight 0.9366) and DRG 159 (Dental and Oral Diseases without CC/MCC, relative weight 0.6893), in Pre-MDC and MDC 03 (Diseases and Disorders of the Ear, Nose, Mouth and Throat), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 528.00 (stomatitis and mucositis, unspecified), 528.3 (cellulitis and abscess of oral soft tissues) and 682.0 (cellulitis and abscess of face).