D80.8
BillableOther immunodeficiencies with predominantly antibody defects
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D80.8 an HCC code?
Yes. D80.8 maps to Disorders of Immunity 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 D80.8
For D80.8to 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 D80.8 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D80.8 is the ICD-10-CM diagnosis code for other immunodeficiencies with predominantly antibody defects. Various other immune system disorders characterized primarily by the body's inability to produce adequate antibodies to fight infections. D80.8 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 certain disorders involving the immune mechanism (d80-d89).
Under the older CMS-HCC V24 model, D80.8 maps to Disorders of Immunity (HCC 47) with a community, non-dual, aged base RAF weight of 0.472. 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.
Use this code only when the specific antibody deficiency does not fit into other D80 categories. Because D80.8 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 D80.8 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code only when the specific antibody deficiency does not fit into other D80 categories
- •Document the specific type of antibody defect identified in clinical evaluation
Clinical Significance
Other immunodeficiencies with predominantly antibody defects encompasses antibody-mediated immunodeficiencies that do not fit into the specifically defined categories of Immunoglobulin A, Immunoglobulin G subclass, or Immunoglobulin M deficiencies. These conditions share the common feature of impaired humoral immunity leading to recurrent infections, but with unique immunological profiles requiring specialized workup.
Documentation Requirements
- ✓Documentation must specify the particular antibody defect identified through immunological testing, explain why it does not fit other D80 subcategories, include quantitative immunoglobulin levels and specific antibody titers, and describe clinical manifestations.
- ✓Document the treatment approach including whether immunoglobulin replacement therapy is required.
Commonly Confused Codes
- •D80.2 through D80.5 (specific immunoglobulin deficiencies that should be used when a specific class or subclass is identified), D80.9 (unspecified antibody deficiency when the specific defect is unknown), D80.6 (antibody deficiency with near-normal immunoglobulins), D83.8 (other common variable immunodeficiency which has distinct diagnostic criteria).