2024 ICD-10-CM Diagnosis Code A09

Infectious gastroenteritis and colitis, unspecified

  • A09 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2024 edition of ICD-10-CM A09 became effective on October 1, 2023.
  • This is the American ICD-10-CM version of A09 – other international versions of ICD-10 A09 may differ.

Applicable To

  • Infectious colitis NOS
  • Infectious enteritis NOS
  • Infectious gastroenteritis NOS

Type 1 Excludes

  • colitis NOS (K52.9)
  • diarrhea NOS (R19.7)
  • enteritis NOS (K52.9)
  • gastroenteritis NOS (K52.9)
  • noninfective gastroenteritis and colitis, unspecified (K52.9)

The following code(s) above A09 contain annotation back-references

 that may be applicable to A09:

  • A00-B99  Certain infectious and parasitic diseases

Approximate Synonyms

  • Infectious colitis
  • Infectious diarrhea
  • Infectious diarrheal disease
  • Infectious gastroenteritis
  • Post-dysenteric arthropathy
  • Post-dysenteric arthropathy of left ankle and/or foot
  • Post-dysenteric arthropathy of left elbow
  • Post-dysenteric arthropathy of left hand
  • Post-dysenteric arthropathy of left hip
  • Post-dysenteric arthropathy of left knee
  • Post-dysenteric arthropathy of left shoulder
  • Post-dysenteric arthropathy of left wrist
  • Post-dysenteric arthropathy of vertebrae
  • Post-dysenteric reactive arthropathy of multiple sites
  • Postdysenteric arthritis of left ankle
  • Postdysenteric arthritis of left elbow
  • Postdysenteric arthritis of left hand
  • Postdysenteric arthritis of left hip
  • Postdysenteric arthritis of left knee
  • Postdysenteric arthritis of left shoulder
  • Postdysenteric arthritis of left wrist
  • Postdysenteric arthritis of multiple sites
  • Postdysenteric arthritis of vertebra
  • Postdysenteric arthropathy
  • Traveler’s diarrhea
  • Travelers diarrhea

Clinical Information

  • A viral or bacterial infectious process affecting the large intestine.

ICD-10-CM A09 is grouped within Diagnostic Related Group(s) (MS-DRG v41.0):

  • 391 Esophagitis, gastroenteritis and miscellaneous digestive disorders with mcc
  • 392 Esophagitis, gastroenteritis and miscellaneous digestive disorders without mcc

Convert A09 to ICD-9-CMCode 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
  • 2021 (effective 10/1/2020): No change
  • 2022 (effective 10/1/2021): No change
  • 2023 (effective 10/1/2022): No change
  • 2024 (effective 10/1/2023): No change

Code annotations containing back-references to A09:

  • Type 1 Excludes: K52.9

Diagnosis Index entries containing back-references to A09: