D59.11
BillableWarm autoimmune hemolytic anemia
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D59.11 an HCC code?
Yes. D59.11 maps to Hemolytic and Aplastic 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 D59.11
For D59.11 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 D59.11 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D59.11 is the ICD-10-CM diagnosis code for warm autoimmune hemolytic anemia. Anemia caused by antibodies that attack red blood cells at normal body temperature, leading to their destruction and resulting in low red blood cell counts. D59.11 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 hemolytic anemias (d55-d59).
Under the CMS-HCC V28 risk adjustment model, D59.11 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, D59.11 maps to Severe Hematological Disorders (HCC 46) with a community, non-dual, aged base RAF weight of 0.666. 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 presence of positive direct antiglobulin test (Coombs test) when available. Because D59.11 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 D59.11 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Document the presence of positive direct antiglobulin test (Coombs test) when available
- •Note any underlying conditions like lupus or lymphoma that may be associated
Clinical Significance
Warm autoimmune hemolytic anemia is the most common form of autoimmune hemolytic anemia, accounting for approximately 70-80% of cases, where immunoglobulin G autoantibodies bind to red blood cells at body temperature (37 degrees Celsius) and cause their destruction primarily in the spleen. It may be primary (idiopathic) or secondary to systemic lupus erythematosus, chronic lymphocytic leukemia, non-Hodgkin lymphoma, or other autoimmune disorders. First-line treatment includes corticosteroids, with rituximab and splenectomy reserved for refractory cases.
Documentation Requirements
- ✓Document the positive direct antiglobulin test showing immunoglobulin G antibody specificity.
- ✓Record hemoglobin levels, reticulocyte count, peripheral blood smear findings (spherocytes, polychromasia), and hemolysis markers.
- ✓Document whether the condition is primary (idiopathic) or secondary to an underlying disease, and code the underlying condition when present.
- ✓Include treatment history and response to corticosteroids or other immunosuppressive agents.
Commonly Confused Codes
- •D59.12 (Cold autoimmune hemolytic anemia) involves immunoglobulin M antibodies reactive at cold temperatures.
- •D59.10 (Autoimmune hemolytic anemia, unspecified) should not be used when warm type is confirmed.
- •D59.13 (Mixed type) applies when both warm and cold antibodies coexist.
- •D58.0 (Hereditary spherocytosis) produces similar spherocyte findings but has a negative Coombs test and hereditary pattern.