D64.0
BillableHereditary sideroblastic anemia
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D64.0 an HCC code?
Yes. D64.0 maps to Hemolytic and Aplastic Anemias under the CMS-HCC V28 risk adjustment model (and Coagulation Defects and Other Specified 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 D64.0
For D64.0 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 D64.0 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D64.0 is the ICD-10-CM diagnosis code for hereditary sideroblastic anemia. An inherited genetic disorder where the body cannot properly use iron to make hemoglobin, resulting in abnormal red blood cells and anemia. D64.0 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 aplastic and other anemias and other bone marrow failure syndromes (d60-d64).
Under the CMS-HCC V28 risk adjustment model, D64.0 maps to Hemolytic and Aplastic Anemias (HCC 109) with a community, non-dual, aged base RAF weight of 0.291. Under the older CMS-HCC V24 model, D64.0 maps to Coagulation Defects and Other Specified Hematological Disorders (HCC 48) with a community, non-dual, aged base RAF weight of 0.209. 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.
Document family history when available to support the hereditary nature of the condition. Because D64.0 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 D64.0 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Document family history when available to support the hereditary nature of the condition
- •Specify the type of hereditary sideroblastic anemia if documented (X-linked, autosomal, etc.)
Clinical Significance
Hereditary sideroblastic anemia is a group of inherited disorders affecting mitochondrial heme biosynthesis, most commonly caused by mutations in the ALAS2 gene (X-linked sideroblastic anemia), resulting in defective hemoglobin production and characteristic ring sideroblasts visible on bone marrow iron staining. Despite having anemia, patients accumulate excess iron in their tissues because the body cannot properly incorporate iron into hemoglobin. The combination of ineffective erythropoiesis and transfusion-dependent anemia can lead to severe iron overload affecting the liver, heart, and endocrine organs.
Documentation Requirements
- ✓Document bone marrow biopsy showing ring sideroblasts (at least 15% of erythroid precursors).
- ✓Record the hereditary nature through family history, inheritance pattern, or genetic testing results identifying the specific mutation.
- ✓Include hemoglobin level, mean corpuscular volume (often microcytic in X-linked forms), serum iron studies (ferritin, transferrin saturation typically elevated), and evidence of iron overload.
- ✓Document treatment with pyridoxine (vitamin B6) supplementation (responsive in some X-linked forms), phlebotomy or chelation therapy for iron overload, and transfusion requirements.