D57.459
BillableSickle-cell thalassemia beta plus with crisis, unspecified
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D57.459 an HCC code?
Yes. D57.459 maps to Sickle Cell Disorders and Thalassemia under the CMS-HCC V28 risk adjustment model (and Severe Hematological Disorders 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 D57.459
For D57.459 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 D57.459 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D57.459 is the ICD-10-CM diagnosis code for sickle-cell thalassemia beta plus with crisis, unspecified. A sickle-cell thalassemia condition experiencing a crisis episode, but the specific type of crisis is not documented or specified. D57.459 sits in the ICD-10-CM chapter for diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (d50-d89), within the section covering hemolytic anemias (d55-d59).
Under the CMS-HCC V28 risk adjustment model, D57.459 maps to Sickle Cell Disorders and Thalassemia (HCC 108) with a community, non-dual, aged base RAF weight of 0.607. Under the older CMS-HCC V24 model, D57.459 maps to Severe Hematological Disorders (HCC 46) with a community, non-dual, aged base RAF weight of 0.666. 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 is a default code when a crisis is present but the specific complication cannot be determined. Because D57.459 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 D57.459 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This is a default code when a crisis is present but the specific complication cannot be determined
- •Query the provider if possible to identify the specific crisis type for more accurate coding
Clinical Significance
Sickle-cell thalassemia beta plus with crisis represents a combined hemoglobinopathy where patients carry both sickle hemoglobin and beta-plus thalassemia trait, currently in an acute crisis state. The unspecified crisis designation means the documentation does not clarify whether the crisis involves vaso-occlusive pain, acute chest syndrome, splenic sequestration, or cerebral vascular events. These patients require urgent evaluation and management, and the lack of crisis specificity represents a documentation gap that should be addressed through provider query.
Documentation Requirements
- ✓Document the specific type of crisis (vaso-occlusive, acute chest syndrome, splenic sequestration, cerebral vascular involvement, or dactylitis).
- ✓Record hemoglobin electrophoresis results confirming beta-plus thalassemia variant.
- ✓Include current hemoglobin/hematocrit levels, reticulocyte count, and any end-organ damage.
- ✓Document pain severity, location, and duration if vaso-occlusive crisis is present.
Commonly Confused Codes
- •D57.419 (Sickle-cell thalassemia beta zero with crisis, unspecified) represents the more severe beta-zero variant where no normal beta-globin is produced.
- •D57.40 vs D57.459 distinguishes the beta-zero from beta-plus subtype.
- •D57.819 (Other sickle-cell disorders with crisis, unspecified) is used when the specific sickle-cell variant is different from thalassemia combinations.