D57.212
BillableSickle-cell/Hb-C disease with splenic sequestration
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D57.212 an HCC code?
Yes. D57.212 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 D57.212
For D57.212 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 D57.212 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D57.212 is the ICD-10-CM diagnosis code for sickle-cell/hb-c disease with splenic sequestration. A blood disorder combining sickle cell disease and hemoglobin C disease where red blood cells become trapped in the spleen, causing it to enlarge and leading to severe anemia and organ dysfunction. D57.212 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, D57.212 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, D57.212 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.
Splenic sequestration is a medical emergency; verify documentation confirms acute sequestration event rather than chronic splenomegaly. Because D57.212 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 D57.212 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Splenic sequestration is a medical emergency; verify documentation confirms acute sequestration event rather than chronic splenomegaly
- •This complication typically requires urgent medical intervention; ensure crisis status is clearly documented
Clinical Significance
Splenic sequestration in sickle-cell/Hemoglobin C disease is an important clinical distinction because Hemoglobin SC patients typically retain splenic function into adulthood (unlike Hemoglobin SS patients who undergo autosplenectomy in childhood). This means Hemoglobin SC patients are at risk for splenic sequestration crises throughout their lifetime, with sudden trapping of blood in the spleen causing acute anemia and potentially hypovolemic shock.
Documentation Requirements
- ✓Documentation must confirm the Hemoglobin SC genotype and the diagnosis of acute splenic sequestration with evidence of rapid splenic enlargement, significant hemoglobin decline from baseline, and clinical signs of acute anemia.
- ✓Record splenic size on exam or imaging, hemoglobin trend, reticulocyte count, platelet count (often decreased due to splenic pooling), treatment including transfusion, and whether splenectomy is recommended.
Commonly Confused Codes
- •D57.212 vs. D57.02 (Hemoglobin SS with splenic sequestration) -
- •different sickle cell genotype. D57.212 vs. D57.219 (Sickle-cell/Hemoglobin C with crisis, unspecified) -
- •use D57.212 when splenic sequestration is specifically documented. D57.212 vs. D73.5 (Infarction of spleen) -
- •splenic infarction and sequestration are different pathologic processes with different clinical presentations.