2026 ICD-10-CM Diagnosis Code A02.23Salmonella arthritis

ICD-10-CM Codes›A00–B99›A00-A09›A02

ICD-10-CM A02.23
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A02.23 is a billable ICD-10-CM diagnosis code for Salmonella arthritis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 548 through 550, 974 through 976. 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 934 closely related codes. Coders also document this condition as localized Salmonella infection. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections and Infective arthritis.

For Medicare Advantage risk adjustment, A02.23 maps to CMS-HCC Category 92 (Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis) under the V28 model, adding a risk factor of about 0.479 for a community, non-dual, aged beneficiary in payment year 2026.

Code Identity

ICD-10-CM Code
A02.23
Billable Status
Yes — Valid for Submission
Code Describes
Salmonella arthritis
Short Description
Salmonella arthritis
Same as the full description in the CMS dataset.
Parent Code
Localized salmonella infections

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA00-A09Intestinal infectious diseases
CategoryA02Other salmonella infections
This CodeA02.23Salmonella arthritis

Medicare Risk Adjustment (HCC)Billing

A02.23 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2026.

CMS-HCC V28 Category (Payment Model)
HCC 92— Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis
Payment HCC · PY 2026 one of 609 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.479
community, non-dual, aged · ranges 0.471–0.632 across segments
Hierarchy
Top of its hierarchy
HCC 92 is not superseded by any other condition category
Prior Model (CMS-HCC V24)
HCC 39
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 39 · ESRD (V21): HCC 39 · ESRD (V24): HCC 39
ESRD V21 weights: 0.061 dialysis, 0.375–0.468 functioning graft · ESRD V24 weights: 0.092 dialysis, 0.431–0.578 functioning graft
Part D (RxHCC)
Not mapped
A02.23 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Localized Salmonella infection
  • Salmonella arthritis

Index to Diseases and InjuriesGuidance

Clinical ClassificationClinical

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

CCSR INF003
Bacterial infections
Default principal diagnosis: inpatient No · outpatient No
CCSR MUS001
Infective arthritis
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Infectious Arthritis

Most kinds of arthritis cause pain and swelling in your joints. Joints are places where two bones meet, such as your elbow or knee. Infectious arthritis is an infection in the joint. The infection comes from a bacterial, viral, or fungal infection that spreads from another part of the body. Symptoms of infectious arthritis include:

Read the full article at MedlinePlus

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

Convert A02.23 to ICD-9-CMHistory

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

ICD-9-CM
003.23 Salmonella arthritis
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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About A02.23Overview

What is the ICD-10 code for Salmonella arthritis?

The ICD-10-CM code for Salmonella arthritis is A02.23 (sometimes written as A0223). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is A02.23 (Localized salmonella infections) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report Salmonella arthritis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does A02.23 group to?

When Salmonella arthritis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 548, 549, 550, 974, 975, 976, with relative weights from 0.8741 to 2.8860 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A02.23 a CC or MCC?

CMS lists A02.23 as a CC (complication or comorbidity) for FY 2026. 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 934 closely related codes in its exclusion list.

What is the ICD-9 equivalent of A02.23?

Under the General Equivalence Mappings, Salmonella arthritis converts to ICD-9-CM 003.23 (Salmonella arthritis). The mapping is a direct match.

What HCC is A02.23?

A02.23 (Salmonella arthritis) maps to CMS-HCC Category 92 (Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis), commonly written as HCC 92, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 39 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.

Does A02.23 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, A02.23 adds a risk adjustment factor of about 0.479 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.471 to 0.632 depending on the payment segment). HCC 92 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 92 category page.