2020 ICD-10-CM Diagnosis Code K21.0

Gastro-esophageal reflux disease with esophagitis

    2016 2017 2018 2019 2020 Billable/Specific Code
  • K21.0 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2020 edition of ICD-10-CM K21.0 became effective on October 1, 2019.
  • This is the American ICD-10-CM version of K21.0 - other international versions of ICD-10 K21.0 may differ.
Applicable To
  • Reflux esophagitis
The following code(s) above K21.0 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to K21.0:
  • K00-K95
    2020 ICD-10-CM Range K00-K95

    Diseases of the digestive system

    Type 2 Excludes
    • certain conditions originating in the perinatal period (P04-P96)
    • certain infectious and parasitic diseases (A00-B99)
    • complications of pregnancy, childbirth and the puerperium (O00-O9A)
    • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
    • endocrine, nutritional and metabolic diseases (E00-E88)
    • injury, poisoning and certain other consequences of external causes (S00-T88)
    • neoplasms (C00-D49)
    • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
    Diseases of the digestive system
  • K20-K31
    2020 ICD-10-CM Range K20-K31

    Diseases of esophagus, stomach and duodenum

    Type 2 Excludes
    Diseases of esophagus, stomach and duodenum
  • K21
    ICD-10-CM Diagnosis Code K21

    Gastro-esophageal reflux disease

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • newborn esophageal reflux (P78.83)
    Gastro-esophageal reflux disease
Approximate Synonyms
  • Reflux esophagitis
ICD-10-CM K21.0 is grouped within Diagnostic Related Group(s) (MS-DRG v37.0):
  • 391 Esophagitis, gastroenteritis and miscellaneous digestive disorders with mcc
  • 392 Esophagitis, gastroenteritis and miscellaneous digestive disorders without mcc

Convert K21.0 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
Code annotations containing back-references to K21.0:
  • Type 1 Excludes: K20
    , K20
    ICD-10-CM Diagnosis Code K20

    Esophagitis

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • erosion of esophagus (K22.1-)
    • esophagitis with gastro-esophageal reflux disease (K21.0)
    • reflux esophagitis (K21.0)
    • ulcerative esophagitis (K22.1-)
    Type 2 Excludes
    • eosinophilic gastritis or gastroenteritis (K52.81)
    Use Additional
    • code to identify:
    • alcohol abuse and dependence (F10.-)
    ICD-10-CM Diagnosis Code K20

    Esophagitis

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • erosion of esophagus (K22.1-)
    • esophagitis with gastro-esophageal reflux disease (K21.0)
    • reflux esophagitis (K21.0)
    • ulcerative esophagitis (K22.1-)
    Type 2 Excludes
    • eosinophilic gastritis or gastroenteritis (K52.81)
    Use Additional
    • code to identify:
    • alcohol abuse and dependence (F10.-)

Diagnosis Index entries containing back-references to K21.0:
  • Allergy, allergic (reaction) (to) T78.40
    ICD-10-CM Diagnosis Code T78.40

    Allergy, unspecified

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Applicable To
    • Allergic reaction NOS
    • Hypersensitivity NOS
    • milk protein Z91.011
      - see also Allergy, food
      ICD-10-CM Diagnosis Code Z91.011

      Allergy to milk products

        2016 2017 2018 2019 2020 Billable/Specific Code POA Exempt
      Type 1 Excludes
      • lactose intolerance (E73.-)
  • Disease, diseased - see also Syndrome
    • gastroesophageal reflux (GERD) K21.9
      ICD-10-CM Diagnosis Code K21.9

      Gastro-esophageal reflux disease without esophagitis

        2016 2017 2018 2019 2020 Billable/Specific Code
      Applicable To
      • Esophageal reflux NOS
      • with esophagitis K21.0
  • Esophagitis (acute) (alkaline) (chemical) (chronic) (infectional) (necrotic) (peptic) (postoperative) K20.9
    ICD-10-CM Diagnosis Code K20.9

    Esophagitis, unspecified

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Esophagitis NOS
    • due to gastrointestinal reflux disease K21.0
    • reflux K21.0
  • Reflux K21.9
    ICD-10-CM Diagnosis Code K21.9

    Gastro-esophageal reflux disease without esophagitis

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Esophageal reflux NOS
    • esophageal K21.9
      ICD-10-CM Diagnosis Code K21.9

      Gastro-esophageal reflux disease without esophagitis

        2016 2017 2018 2019 2020 Billable/Specific Code
      Applicable To
      • Esophageal reflux NOS
      • with esophagitis K21.0
    • gastroesophageal K21.9
      ICD-10-CM Diagnosis Code K21.9

      Gastro-esophageal reflux disease without esophagitis

        2016 2017 2018 2019 2020 Billable/Specific Code
      Applicable To
      • Esophageal reflux NOS
      • with esophagitis K21.0
  • Ulcer, ulcerated, ulcerating, ulceration, ulcerative
    • esophagus (peptic) K22.10
      ICD-10-CM Diagnosis Code K22.10

      Ulcer of esophagus without bleeding

        2016 2017 2018 2019 2020 Billable/Specific Code
      Applicable To
      • Ulcer of esophagus NOS
      • due to
        • gastrointestinal reflux disease K21.0

ICD-10-CM Codes Adjacent To K21.0
K14.4 Atrophy of tongue papillae
K14.5 Plicated tongue
K14.6 Glossodynia
K14.8 Other diseases of tongue
K14.9 Disease of tongue, unspecified
K20 Esophagitis
K20.0 Eosinophilic esophagitis
K20.8 Other esophagitis
K20.9 Esophagitis, unspecified
K21 Gastro-esophageal reflux disease
K21.0 Gastro-esophageal reflux disease with esophagitis
K21.9 Gastro-esophageal reflux disease without esophagitis
K22 Other diseases of esophagus
K22.0 Achalasia of cardia
K22.1 Ulcer of esophagus
K22.10 …… without bleeding
K22.11 …… with bleeding
K22.2 Esophageal obstruction
K22.3 Perforation of esophagus
K22.4 Dyskinesia of esophagus
K22.5 Diverticulum of esophagus, acquired

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.