DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Subcategory · FY2027

K21.0 Gastro-esophageal reflux disease with esophagitis

  • Header · not billable

K21.0 is not billable. The subcategory heads 2 billable codes in FY2027: the 2 codes directly below it.

Index → code

  • Esophagitis (acute) (alkaline) (chemical) (chronic) (infectional) (necrotic) (peptic) (postoperative) (without bleeding)reflux → K21.00
  • Esophagitis (acute) (alkaline) (chemical) (chronic) (infectional) (necrotic) (peptic) (postoperative) (without bleeding)due to gastrointestinal reflux disease (without bleeding) → K21.00
  • Refluxesophagealwith esophagitis (without bleeding) → K21.00

Where it sits

  1. Chapter 11 Diseases of the digestive system (K00-K95)
  2. K20-K31 Diseases of esophagus, stomach and duodenum (K20-K31)
  3. K21 Gastro-esophageal reflux disease
  4. K21.0 Gastro-esophageal reflux disease with esophagitis
Billable codes
2
Subdivisions
2
CC / MCC codes
0 / 1
HCC V28 codes
0
New FY2027
0
Index entries
7

Codes in K21.0

  1. K21.00
    Gastro-esophageal reflux disease with esophagitis, without bleeding 1 billable code
    Billable
  2. K21.01
    Gastro-esophageal reflux disease with esophagitis, with bleeding
    BillableMCC

CC/MCC: as a secondary diagnosis, unless the principal diagnosis is on the code’s PDX exclusion list (MS-DRG v44 Appendix C; list on the code card).

Sources of each column.

Instructions

Notes that also apply

Excludes1 from K21

  • newborn esophageal reflux (P78.83) P78.83

Block K20-K31 instructions (Excludes2 1): printed on the block page.

Chapter 11 instructions (Excludes2 8): printed on the chapter 11 page.

Index entries

  • Esophagitis (acute) (alkaline) (chemical) (chronic) (infectional) (necrotic) (peptic) (postoperative) (without bleeding)due to gastrointestinal reflux disease (without bleeding)with bleeding → K21.01
  • Esophagitis (acute) (alkaline) (chemical) (chronic) (infectional) (necrotic) (peptic) (postoperative) (without bleeding)refluxwith bleeding → K21.01
  • Disease, diseasedgastroesophageal reflux (GERD)with esophagitis (without bleeding)with bleeding → K21.01
  • Refluxesophagealwith esophagitis (without bleeding)with bleeding → K21.01
  • Refluxgastroesophagealwith esophagitis (without bleeding)with bleeding → K21.01
  • Allergy, allergic (reaction) (to)milk proteingastroesophageal refluxwith esophagitis (without bleeding)with bleeding → K21.01
  • Ulcer, ulcerated, ulcerating, ulceration, ulcerativeesophagus (peptic)due togastrointestinal reflux disease (without bleeding)with bleeding → K21.01

NCHS Alphabetic Index. Index first, then the Tabular List.

Hierarchy