D64.2
BillableSecondary sideroblastic anemia due to drugs and toxins
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D64.2 an HCC code?
Yes. D64.2 maps to Coagulation Defects and Other Specified Hematological Disorders under the V24 model but is not retained in V28.
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 D64.2
For D64.2to 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 D64.2 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D64.2 is the ICD-10-CM diagnosis code for secondary sideroblastic anemia due to drugs and toxins. A type of anemia where the bone marrow produces abnormal red blood cells due to exposure to certain medications or toxic substances. D64.2 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 older CMS-HCC V24 model, D64.2 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.
Always identify and document the specific drug or toxin causing the condition. Because D64.2 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 D64.2 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Always identify and document the specific drug or toxin causing the condition
- •Use an additional code to specify the drug or toxin using the Table of Drugs and Chemicals
Clinical Significance
Secondary sideroblastic anemia due to drugs and toxins occurs when medications or toxic exposures impair mitochondrial heme synthesis, causing ring sideroblast formation in the bone marrow. The most common causative agents include isoniazid (which depletes pyridoxine, a cofactor in heme synthesis), chloramphenicol, cycloserine, linezolid, lead exposure, ethanol (chronic alcoholism is a leading cause), and zinc excess. The condition is typically reversible upon discontinuation of the offending agent and supplementation with pyridoxine when appropriate.
Documentation Requirements
- ✓Document the specific causative drug or toxin by name with temporal relationship to anemia onset.
- ✓Record bone marrow biopsy findings showing ring sideroblasts.
- ✓Include hemoglobin level, mean corpuscular volume, serum iron studies, and pyridoxine level when relevant.
- ✓Use external cause codes to identify the responsible agent.
- ✓Document whether the offending agent has been discontinued and whether pyridoxine supplementation has been initiated.
- ✓Record response to treatment and hemoglobin recovery timeline.
Use Additional Code
Commonly Confused Codes
- •D64.0 (Hereditary sideroblastic anemia) is for inherited genetic forms.
- •D64.1 (Secondary sideroblastic anemia due to disease) is caused by underlying medical conditions rather than drugs.
- •D59.2 (Drug-induced nonautoimmune hemolytic anemia) involves red blood cell destruction rather than production defects.
- •D61.1 (Drug-induced aplastic anemia) affects all cell lines, not just erythropoiesis.
- •D64.3 (Other sideroblastic anemias) is a less specific alternative.