A39.2
BillableAcute meningococcemia
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is A39.2 an HCC code?
Yes. A39.2 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 A39.2
For A39.2 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 A39.2 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
A39.2 is the ICD-10-CM diagnosis code for acute meningococcemia. A serious bloodstream infection caused by meningococcal bacteria that develops rapidly and can be life-threatening. This condition occurs when the bacteria multiply in the blood and can lead to sepsis, organ failure, or meningitis if not treated immediately. A39.2 sits in the ICD-10-CM chapter for certain infectious and parasitic diseases (a00-b99), within the section covering other bacterial diseases (a30-a49).
Under the CMS-HCC V28 risk adjustment model, A39.2 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 A39.2 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.
This code represents the acute phase of meningococcal infection; verify documentation specifies meningococcemia (blood infection) rather than meningitis (brain/spinal cord infection), which would use a different code. Because A39.2 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 A39.2 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This code represents the acute phase of meningococcal infection; verify documentation specifies meningococcemia (blood infection) rather than meningitis (brain/spinal cord infection), which would use a different code
- •Look for associated complications such as sepsis (R65.2x), acute respiratory distress syndrome, or disseminated intravascular coagulation, as these should be coded separately to capture disease severity
Clinical Significance
Acute meningococcemia is a rapidly progressive bloodstream infection with Neisseria meningitidis that can progress from initial symptoms to death within hours. It is characterized by petechial/purpuric rash, high fever, and potential for fulminant septic shock. Immediate empiric antibiotic therapy and close contacts' chemoprophylaxis are critical.
Documentation Requirements
- ✓Blood cultures or PCR positive for Neisseria meningitidis, or clinical diagnosis with characteristic presentation
- ✓Documentation of acuity — acute presentation with rapid onset
- ✓Rash description (petechiae, purpura, purpura fulminans)
- ✓Hemodynamic status and organ dysfunction assessment
- ✓Serogroup identification if available (A, B, C, W, X, Y) for epidemiologic purposes