2027 ICD-10-CM Diagnosis Code A05.4Foodborne Bacillus cereus intoxication

ICD-10-CM Codes›A00–B99›A00-A09›A05

ICD-10-CM A05.4
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A05.4 is a billable ICD-10-CM diagnosis code for foodborne Bacillus cereus intoxication. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 371 through 373. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 81 closely related codes. Coders also document this condition as food poisoning caused by Bacillus cereus. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Foodborne intoxications.

Code Identity

ICD-10-CM Code
A05.4
Billable Status
Yes — Valid for Submission
Code Describes
Foodborne Bacillus cereus intoxication
Short Description
Foodborne Bacillus cereus intoxication
Same as the full description in the CMS dataset.
Parent Code
Other bacterial foodborne intoxications, not elsewhere classified

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA00-A09Intestinal infectious diseases
CategoryA05Other bacterial foodborne intoxications, not elsewhere classified
This CodeA05.4Foodborne Bacillus cereus intoxication

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Food poisoning caused by Bacillus cereus

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A05.4: its own notes plus those printed at A05 and 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.

From A05 Other bacterial foodborne intoxications, not elsewhere classified applies to 8 codes
  • Clostridium difficile foodborne intoxication and infection (A04.7-)
  • Escherichia coli infection (A04.0-A04.4)
  • listeriosis (A32.-)
  • salmonella foodborne intoxication and infection (A02.-)
  • toxic effect of noxious foodstuffs (T61-T62)

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 A05.4, its category, or a range that includes it.

Excludes1 4

These codes carry an Excludes1 note naming A05.4: they are not reported together with it, unless the two conditions are unrelated.

  • A04 Other bacterial intestinal infections
    bacterial foodborne intoxications, NEC (A05.-) names A05.-, which includes this code
  • T61 Toxic effect of noxious substances eaten as seafood
    bacterial foodborne intoxications (A05.-) names A05.-, which includes this code
  • T62 Toxic effect of other noxious substances eaten as food
    bacterial food borne intoxications (A05.-) names A05.-, which includes this code
  • T78.1 Other adverse food reactions, not elsewhere classified
    bacterial food borne intoxications (A05.-) names A05.-, which includes this code

Excludes2 2

These codes carry an Excludes2 note naming A05.4: 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

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INF005
Foodborne intoxications
Default principal diagnosis: inpatient Yes · outpatient Yes

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.

Convert A05.4 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
005.89 Bact food poisoning NEC
Approximate The match is approximate rather than exact.

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 A05.4Overview

What is the ICD-10 code for foodborne Bacillus cereus intoxication?

The ICD-10-CM code for foodborne Bacillus cereus intoxication is A05.4 (sometimes written as A054). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is A05.4 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report foodborne Bacillus cereus intoxication on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does A05.4 group to?

When foodborne Bacillus cereus intoxication is the principal diagnosis on an inpatient stay, it groups to MS-DRG 372, 371, 373, with relative weights from 0.6945 to 1.7087 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A05.4 a CC or MCC?

CMS lists A05.4 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 81 closely related codes in its exclusion list.

Can A05.4 be reported with a code from A04.7?

Not as a rule. The Excludes1 note at A05, which applies to A05.4, lists "Clostridium difficile foodborne intoxication and infection (A04.7-)". 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).