2027 ICD-10-CM Diagnosis Code A02.21Salmonella meningitis

ICD-10-CM Codes›A00–B99›A00-A09›A02

ICD-10-CM A02.21
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A02.21 is a billable ICD-10-CM diagnosis code for Salmonella meningitis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 23 through 24, 94 through 96, 974 through 976. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 54 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections and Meningitis.

Code Identity

ICD-10-CM Code
A02.21
Billable Status
Yes — Valid for Submission
Code Describes
Salmonella meningitis
Short Description
Salmonella meningitis
Same as the full description in the CMS dataset.
Parent Code
A02.2
Localized salmonella infections

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA00-A09Intestinal infectious diseases
CategoryA02Other salmonella infections
This CodeA02.21Salmonella meningitis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Salmonella meningitis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A02.21: its own notes plus those printed at A02 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 A02 Other salmonella infections applies to 11 codes
  • infection or foodborne intoxication due to any Salmonella species other than S. typhi and S. paratyphi
From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

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 A02.21, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming A02.21: they are not reported together with it, unless the two conditions are unrelated.

  • A05 Other bacterial foodborne intoxications, not elsewhere classified
    salmonella foodborne intoxication and infection (A02.-) names A02.-, which includes this code

Excludes2 2

These codes carry an Excludes2 note naming A02.21: 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 A02.21 is one of the conditions named.

  • M49 Spondylopathies in diseases classified elsewhere
    enterobacterial infections (A01-A04) names A01-A04, 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 INF003
Bacterial infections
Default principal diagnosis: inpatient No · outpatient No
CCSR NVS001
Meningitis
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Meningitis

Meningitis is inflammation of the thin tissue that surrounds the brain and spinal cord, called the meninges. There are several types of meningitis. The most common is viral meningitis. You get it when a virus enters the body through the nose or mouth and travels to the brain. Bacterial meningitis is rare but can be deadly.

Read the full article at MedlinePlus

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

Convert A02.21 to ICD-9-CMHistory

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

ICD-9-CM
003.21 Salmonella meningitis
Exact Match The mapping is direct, with no qualifiers.

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 A02.21Overview

What is the ICD-10 code for Salmonella meningitis?

The ICD-10-CM code for Salmonella meningitis is A02.21 (sometimes written as A0221). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is A02.21 (Localized salmonella infections) a billable code?

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

What MS-DRG does A02.21 group to?

When Salmonella meningitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 24, 974, 976, 975, 23, 96, 95, 94, with relative weights from 0.7879 to 5.7422 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A02.21 a CC or MCC?

CMS lists A02.21 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 54 closely related codes in its exclusion list.

What is the ICD-9 equivalent of A02.21?

Under the General Equivalence Mappings, Salmonella meningitis converts to ICD-9-CM 003.21 (Salmonella meningitis). The mapping is a direct match.