D80.1
BillableNonfamilial hypogammaglobulinemia
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is D80.1 an HCC code?
Yes. D80.1 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 D80.1
For D80.1to 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 D80.1 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
D80.1 is the ICD-10-CM diagnosis code for nonfamilial hypogammaglobulinemia. A condition where the body produces abnormally low levels of antibodies that is not inherited or familial. D80.1 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, D80.1 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 when hypogammaglobulinemia is acquired rather than genetic. Because D80.1 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 D80.1 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code when hypogammaglobulinemia is acquired rather than genetic
- •Document the underlying cause if known (e.g., medication-related, secondary to other disease)
Clinical Significance
Nonfamilial hypogammaglobulinemia is an acquired form of antibody deficiency where immunoglobulin levels are abnormally low without a hereditary or genetic basis. This condition may result from medications, protein-losing conditions, or unknown causes, and predisposes patients to recurrent sinopulmonary and gastrointestinal infections requiring immunoglobulin replacement therapy.
Documentation Requirements
- ✓Documentation should include quantitative immunoglobulin levels demonstrating low Immunoglobulin G (and potentially Immunoglobulin A and Immunoglobulin M), absence of family history suggesting hereditary cause, potential causative factors (medications, underlying disease), frequency and types of infections, and current treatment including immunoglobulin replacement dosing and schedule.
- ✓Document that the condition is acquired, not inherited.
Commonly Confused Codes
- •D80.0 (hereditary hypogammaglobulinemia, which requires genetic/familial etiology), D83.9 (common variable immunodeficiency, a distinct diagnostic entity with specific criteria), D80.9 (unspecified antibody deficiency when the nonfamilial nature is not documented), D89.9 (unspecified immune disorder, far less specific).