2027 ICD-10-CM Diagnosis Code A04Other bacterial intestinal infections

ICD-10-CM Codes›A00–B99›A00-A09›A04

ICD-10-CM A04
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A04 is a non-billable ICD-10-CM category code for other bacterial intestinal infections, so it cannot be submitted on claims. Use a more specific code from this category instead, such as A04.0, A04.1, A04.2, and A04.3.

Code Identity

ICD-10-CM Code
A04
Billable Status
No — Non-Billable Category
Code Describes
Other bacterial intestinal infections
Short Description
Other bacterial intestinal infections
Same as the full description in the CMS dataset.
Chapter
A00-A09
Intestinal infectious diseases

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA00-A09Intestinal infectious diseases
CategoryA04Other bacterial intestinal infections
This CodeA04Other bacterial intestinal infections

Specific Coding for Other bacterial intestinal infectionsOverview

Non-specific codes like A04 require more characters. Use one of these billable codes instead:

  • Use A04.0 for Enteropathogenic Escherichia coli infection

  • Use A04.1 for Enterotoxigenic Escherichia coli infection

  • Use A04.2 for Enteroinvasive Escherichia coli infection

  • Use A04.3 for Enterohemorrhagic Escherichia coli infection

  • Use A04.4 for Other intestinal Escherichia coli infections

  • Use A04.5 for Campylobacter enteritis

  • Use A04.6 for Enteritis due to Yersinia enterocolitica

  • A04.7 for Enterocolitis due to Clostridium difficile

  • Use A04.71 for Enterocolitis due to Clostridium difficile, recurrent

  • Use A04.72 for Enterocolitis due to Clostridium difficile, not specified as recurrent

  • Use A04.8 for Other specified bacterial intestinal infections

  • Use A04.9 for Bacterial intestinal infection, unspecified

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A04: its own notes plus those printed at Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

  • bacterial foodborne intoxications, NEC (A05.-)
  • tuberculous enteritis (A18.32)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name A04, its category, or a range that includes it.

Excludes2 2

These codes carry an Excludes2 note naming A04: its condition is not part of those codes, and both may be reported when the patient has both.

  • Block P35-P39 Infections specific to the perinatal period
    intestinal infectious disease (A00-A09) names A00-A09, which includes this code
  • P37 Other congenital infectious and parasitic diseases
    infectious neonatal diarrhea (A00-A09) names A00-A09, which includes this code

Code First 1

These codes say to code first a condition named in the note, and A04 is one of the conditions named.

  • M49 Spondylopathies in diseases classified elsewhere
    enterobacterial infections (A01-A04) names A01-A04, which includes this code

Patient EducationClinical

Bacterial Infections

Bacteria are tiny organisms (living things) that have only one cell. Under a microscope, they look like balls, rods, or spirals. They can be found almost everywhere on Earth. There are lots of bacteria in and on your body. In fact, your body has about 10 times more bacteria cells than human cells.

The full article covers:

  • What are bacteria?
  • How do bacterial infections spread?
  • What are the treatments for bacterial infections?
  • Can bacterial infections be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About A04Overview

What is the ICD-10 code for other bacterial intestinal infections?

A04 is the ICD-10-CM category for other bacterial intestinal infections, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is A04 (Other bacterial intestinal infections) a billable code?

No. This is a category header that groups the codes for other bacterial intestinal infections, and headers cannot be submitted on claims. Claims for other bacterial intestinal infections need a more specific code from this category, such as A04.0, A04.1, and A04.2.

Can A04 be reported with a code from A05?

Not as a rule. The Excludes1 note on A04 lists "bacterial foodborne intoxications, NEC (A05.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).