D57.418
BillableSickle-cell thalassemia, unspecified, with crisis with other specified complication
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D57.418 an HCC code?
Yes. D57.418 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 D57.418
For D57.418 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 D57.418 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D57.418 is the ICD-10-CM diagnosis code for sickle-cell thalassemia, unspecified, with crisis with other specified complication. A combination blood disorder mixing sickle-cell disease and thalassemia that causes a crisis with additional complications beyond the typical sickle-cell crisis symptoms. D57.418 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, D57.418 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, D57.418 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.
Ensure documentation specifies the exact complication beyond standard crisis (e.g., infection, organ damage) to justify the 'other specified' designation. Because D57.418 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 D57.418 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Ensure documentation specifies the exact complication beyond standard crisis (e.g., infection, organ damage) to justify the 'other specified' designation
- •Verify the thalassemia type is unspecified before assigning this code; if beta-zero or beta-plus is documented, use the more specific codes D57.43x or D57.45x
Clinical Significance
This code captures sickle-cell thalassemia (unspecified type) crises with specified complications not classified under acute chest syndrome, splenic sequestration, cerebral vascular involvement, or dactylitis. These may include priapism, hepatic sequestration, aplastic crisis, renal crisis, or other organ-specific vaso-occlusive events in patients whose thalassemia subtype (beta-zero vs. beta-plus) is undocumented.
Documentation Requirements
- ✓Documentation must confirm the sickle-cell thalassemia genotype, identify the specific crisis complication, and query for beta-zero vs.
- ✓beta-plus specification.
- ✓The provider should describe the complication type, clinical presentation, diagnostic findings, treatment, and outcome.
- ✓Document why the complication does not fit D57.411-D57.414 categories.
Commonly Confused Codes
- •D57.418 vs. D57.438 (Beta zero with other specified complication) -
- •use when beta-zero is confirmed. D57.418 vs. D57.458 (Beta plus with other specified complication) -
- •use when beta-plus is confirmed. D57.418 vs. D57.419 (Sickle-cell thalassemia with crisis, unspecified) -
- •use D57.418 when a specific complication is identified. D57.418 vs. D57.09 (Hemoglobin SS with other specified complication) -
- •different genotype.