D64.3
BillableOther sideroblastic anemias
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D64.3 an HCC code?
Yes. D64.3 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 D64.3
For D64.3 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 D64.3 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D64.3 is the ICD-10-CM diagnosis code for other sideroblastic anemias. A group of anemias characterized by abnormal iron accumulation in red blood cells that are not caused by drugs, toxins, or genetic factors. D64.3 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, D64.3 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, D64.3 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.
This is a catch-all code for sideroblastic anemias not classified elsewhere. Because D64.3 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 D64.3 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This is a catch-all code for sideroblastic anemias not classified elsewhere
- •Ensure the anemia is not secondary to drugs, toxins, or congenital conditions before assigning this code
Clinical Significance
Other sideroblastic anemias captures sideroblastic anemia cases that do not fit into hereditary (D64.0), disease-related secondary (D64.1), or drug/toxin-related secondary (D64.2) categories. This includes idiopathic acquired sideroblastic anemia without meeting full criteria for myelodysplastic syndrome, pyridoxine-responsive sideroblastic anemia of unclear etiology, and sideroblastic anemia associated with mitochondrial disorders not otherwise classified. The common feature is impaired heme synthesis with ring sideroblast formation on bone marrow examination.
Documentation Requirements
- ✓Document bone marrow biopsy findings showing ring sideroblasts with percentage quantification.
- ✓Record the evaluation performed to exclude hereditary, drug-induced, and disease-related causes.
- ✓Include hemoglobin level, mean corpuscular volume, reticulocyte count, serum iron studies, and ferritin level.
- ✓Document any pyridoxine trial results to assess responsiveness.
- ✓Note whether myelodysplastic syndrome has been considered and excluded through cytogenetic analysis and morphological review.