ICD-10-CM 2027 diagnosis code
A04Other bacterial intestinal infections
A04 is a header code, so it can't be reported by itself. Choose one of the 10 more specific codes beneath it.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About A04
A04 is the ICD-10-CM diagnosis code for other bacterial intestinal infections. It belongs to block A00-A09 (intestinal infectious diseases) and chapter 1 (certain infectious and parasitic diseases). It is a header code, so it can't be reported by itself; one of its 10 subcodes must be used instead.
To report this condition, pick the subcode that matches the documentation: A04.0 (infection), A04.1 (infection), A04.2 (infection), A04.3 (infection), A04.4 (infections), A04.5 (enteritis), A04.6 (enterocolitica), A04.7 (difficile) and 2 more.
Don't report A04 together with the conditions in its Excludes1 note: bacterial foodborne intoxications, NEC (A05.-) and tuberculous enteritis (A18.32).
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Specific codes under A04
- A04.0Enteropathogenic Escherichia coli infectionBillable
- A04.1Enterotoxigenic Escherichia coli infectionBillable
- A04.2Enteroinvasive Escherichia coli infectionBillable
- A04.3Enterohemorrhagic Escherichia coli infectionBillable
- A04.4Other intestinal Escherichia coli infectionsBillable
- A04.5Campylobacter enteritisBillable
- A04.6Enteritis due to Yersinia enterocoliticaBillable
- A04.7Enterocolitis due to Clostridium difficile
- A04.8Other specified bacterial intestinal infectionsBillable
- A04.9Bacterial intestinal infection, unspecifiedBillable
Coding notes
Notes that apply from higher levels
Instructions written at a parent level also apply to A04.
Broader instructions also apply from Chapter 1: Certain infectious and parasitic diseases.
Codes whose notes reference A04
- M49Code first
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about A04
Is A04 billable?
- No. A04 is a header code. Report one of its more specific subcodes instead.