D61.2
BillableAplastic anemia due to other external agents
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D61.2 an HCC code?
Yes. D61.2 maps to Acquired Hemolytic, Aplastic, and Sideroblastic Anemias 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 D61.2
For D61.2to 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 D61.2 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D61.2 is the ICD-10-CM diagnosis code for aplastic anemia due to other external agents. A serious condition where exposure to external agents (such as chemicals, radiation, or toxins) causes the bone marrow to stop producing blood cells. D61.2 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 CMS-HCC V28 risk adjustment model, D61.2 maps to Acquired Hemolytic, Aplastic, and Sideroblastic Anemias (HCC 109) with a community, non-dual, aged base RAF weight of 1.144. Under the older CMS-HCC V24 model, D61.2 maps to Severe Hematological Disorders (HCC 46) with a community, non-dual, aged base RAF weight of 1.372. 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 the specific external agent responsible (e.g., benzene, pesticides, radiation); include details about exposure duration and intensity. Because D61.2 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 D61.2 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
Clinical Significance
Aplastic anemia due to other external agents encompasses bone marrow failure caused by non-drug environmental exposures including ionizing radiation (accidental or occupational), benzene and other industrial chemicals, pesticides, and certain toxins. Radiation-induced aplastic anemia severity depends on dose, with whole-body exposures above 2 Gray causing clinically significant marrow suppression. Chronic benzene exposure is a well-established cause of aplastic anemia and can also progress to myelodysplastic syndrome or acute leukemia due to its mutagenic properties.
Documentation Requirements
- ✓Document the specific external agent responsible (radiation type and dose, chemical name, toxin identity) with exposure duration and intensity.
- ✓Include occupational history and environmental exposure assessment.
- ✓Record complete blood count, bone marrow biopsy showing hypocellularity, and disease severity classification.
- ✓Document treatment approach and response.
- ✓Use Chapter 20 external cause codes (V00-Y99) to capture the source and circumstances of exposure.
- ✓Include any regulatory reporting requirements for occupational exposures.
Commonly Confused Codes
- •D61.1 (Drug-induced aplastic anemia) is specifically for medication-related causes.
- •D61.3 (Idiopathic aplastic anemia) is used when no external cause is identified.
- •D61.9 (Aplastic anemia, unspecified) does not specify the etiology.
- •D61.810 (Antineoplastic chemotherapy induced pancytopenia) is for intentional chemotherapy effects.
- •T66 (Radiation sickness, unspecified) may be an additional code for radiation exposure cases.