A02.1
BillableSalmonella sepsis
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is A02.1 an HCC code?
Yes. A02.1 maps to Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock under the CMS-HCC V28 risk adjustment model (and Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock 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 A02.1
For A02.1 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 A02.1 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
A02.1 is the ICD-10-CM diagnosis code for salmonella sepsis. A serious bloodstream infection caused by Salmonella bacteria that has spread throughout the body, causing a life-threatening systemic response. This condition requires immediate medical treatment and can lead to organ failure if not properly managed. A02.1 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, A02.1 maps to Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock (HCC 2) with a community, non-dual, aged base RAF weight of 0.455. The V24 model used during the PY2024–PY2025 transition mapped A02.1 the same way and at the same RAF weight. 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.
Salmonella sepsis is a combination code that includes both the organism identification and the sepsis condition, so do not code sepsis separately with a different code. Because A02.1 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 A02.1 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Salmonella sepsis is a combination code that includes both the organism identification and the sepsis condition, so do not code sepsis separately with a different code
- •Verify documentation clearly states 'sepsis' or 'septicemia' related to Salmonella infection; if only gastroenteritis is documented, use A02.0 instead
Clinical Significance
Salmonella sepsis is a life-threatening bloodstream infection caused by Salmonella species, most commonly affecting immunocompromised patients, the elderly, and those with sickle cell disease. It carries high mortality risk and requires emergent treatment with appropriate antibiotics and hemodynamic support.
Documentation Requirements
- ✓Blood cultures positive for Salmonella species or clinical documentation of Salmonella sepsis
- ✓Documentation of systemic inflammatory response (fever, tachycardia, hypotension, altered mental status)
- ✓Organ dysfunction assessment if present (acute kidney injury, respiratory failure, coagulopathy)
- ✓Underlying conditions predisposing to Salmonella sepsis (HIV/AIDS, sickle cell disease, immunosuppression)
- ✓If severe sepsis or septic shock is present, document the specific organ dysfunction and use additional codes (R65.20 or R65.21)
Commonly Confused Codes
- •A41.9 (Sepsis, unspecified organism) — Use A02.1 when Salmonella is the identified causative organism, not the unspecified sepsis code
- •A01.00 (Typhoid fever) — Use A02.1 for non-typhi Salmonella sepsis; typhoid sepsis would be coded under A01 series
- •A02.0 (Salmonella enteritis) — A02.0 is for GI infection only; use A02.1 when the infection has progressed to sepsis