D47.3
BillableEssential (hemorrhagic) thrombocythemia
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D47.3 an HCC code?
Yes. D47.3 maps to Melanoma and Other Skin Cancers 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 D47.3
For D47.3 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 D47.3 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D47.3 is the ICD-10-CM diagnosis code for essential (hemorrhagic) thrombocythemia. Essential thrombocythemia is a blood disorder where the bone marrow produces too many platelets, which can lead to abnormal bleeding or clotting. This is a chronic condition that requires ongoing monitoring and management. D47.3 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes (d37-d48).
Under the CMS-HCC V28 risk adjustment model, D47.3 maps to Melanoma and Other Skin Cancers (HCC 23) with a community, non-dual, aged base RAF weight of 0.251. Under the older CMS-HCC V24 model, D47.3 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.
Verify documentation specifies 'essential' or 'primary' thrombocythemia to distinguish from secondary causes of high platelet counts. Because D47.3 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 D47.3 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify documentation specifies 'essential' or 'primary' thrombocythemia to distinguish from secondary causes of high platelet counts
- •Look for associated complications (thrombosis, hemorrhage) that may require additional codes, and confirm whether the patient is on antiplatelet or anticoagulant therapy
Clinical Significance
Essential thrombocythemia is a chronic myeloproliferative neoplasm characterized by persistent thrombocytosis (platelet count above 450,000/microL) due to clonal megakaryocyte proliferation. Despite being considered the most indolent of the myeloproliferative neoplasms, it carries risks of both thrombotic events (stroke, deep vein thrombosis) and paradoxical hemorrhagic complications from acquired von Willebrand disease.
Documentation Requirements
- ✓Documentation should include persistently elevated platelet counts, bone marrow biopsy showing megakaryocyte hyperplasia, and molecular testing (JAK2, CALR, or MPL mutations).
- ✓World Health Organization diagnostic criteria should be met.
- ✓Document cardiovascular risk factors, prior thrombotic events, and current therapy (aspirin, hydroxyurea, anagrelide).
- ✓Rule out reactive thrombocytosis.