A02.24
BillableSalmonella osteomyelitis
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is A02.24 an HCC code?
Yes. A02.24 maps to Bone/Joint/Muscle Infections/Necrosis under the CMS-HCC V28 risk adjustment model (and Bone/Joint/Muscle Infections/Necrosis under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for A02.24
For A02.24 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed A02.24 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
A02.24 is the ICD-10-CM diagnosis code for salmonella osteomyelitis. A bone infection caused by Salmonella bacteria, which is a type of food-borne pathogen that can spread through the bloodstream and infect the bone tissue. This condition causes inflammation, pain, and potential bone damage if left untreated. A02.24 sits in the ICD-10-CM chapter for certain infectious and parasitic diseases (a00-b99), within the section covering intestinal infectious diseases (a00-a09).
Under the CMS-HCC V28 risk adjustment model, A02.24 maps to Bone/Joint/Muscle Infections/Necrosis (HCC 92) with a community, non-dual, aged base RAF weight of 0.209. Under the older V24 model, A02.24 mapped to the same category but with a base RAF weight of 0.482 — V28 recalibrated weights across the entire model. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Verify the specific bone site affected and use an additional code from category M86 if needed to specify the anatomical location (e.g., femur, tibia, humerus). Because A02.24 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for A02.24 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify the specific bone site affected and use an additional code from category M86 if needed to specify the anatomical location (e.g., femur, tibia, humerus)
- •Confirm the diagnosis is documented as Salmonella osteomyelitis and not another type of bacterial osteomyelitis, as this distinction is important for treatment and epidemiological tracking
Clinical Significance
Salmonella osteomyelitis is a bone infection caused by non-typhi Salmonella species, classically associated with sickle cell disease where it is the most common cause of osteomyelitis. It requires prolonged antibiotic therapy and may need surgical intervention, representing substantial healthcare resource utilization.
Documentation Requirements
- ✓Bone culture or blood culture identifying Salmonella species with radiographic evidence of bone involvement
- ✓MRI, bone scan, or CT imaging confirming osteomyelitis
- ✓Specific bone(s) and anatomic location(s) affected
- ✓Acuity — acute vs. chronic osteomyelitis
- ✓Underlying risk factors documented (sickle cell disease, immunosuppression, prosthetic hardware)
Commonly Confused Codes
- •A01.05 (Typhoid osteomyelitis) — Use A01.05 for S. typhi bone infections; A02.24 is for non-typhi Salmonella species
- •M86.9 (Osteomyelitis, unspecified) — Use A02.24 when Salmonella is the documented organism, not the generic osteomyelitis code
- •M86.60 (Other chronic osteomyelitis, unspecified site) — A02.24 is the correct code when the organism is identified as Salmonella