E88.01
BillableAlpha-1-antitrypsin deficiency
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is E88.01 an HCC code?
Yes. E88.01 maps to Glycogen/Amino-Acid/Other Metabolic Disorders under the CMS-HCC V28 risk adjustment model (and Other Significant Endocrine and Metabolic 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 E88.01
For E88.01 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 E88.01 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
E88.01 is the ICD-10-CM diagnosis code for alpha-1-antitrypsin deficiency. A genetic condition where the body doesn't produce enough alpha-1-antitrypsin, a protein that protects the lungs and liver from damage. E88.01 sits in the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89), within the section covering metabolic disorders (e70-e88).
Under the CMS-HCC V28 risk adjustment model, E88.01 maps to Glycogen/Amino-Acid/Other Metabolic Disorders (HCC 50) with a community, non-dual, aged base RAF weight of 0.289. Under the older CMS-HCC V24 model, E88.01 maps to Other Significant Endocrine and Metabolic Disorders (HCC 23) with a community, non-dual, aged base RAF weight of 0.230. 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 if this is the primary diagnosis or secondary to lung/liver disease; document any associated COPD or emphysema separately. Because E88.01 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 E88.01 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Verify if this is the primary diagnosis or secondary to lung/liver disease; document any associated COPD or emphysema separately
- •Check for family history documentation and whether genetic testing was performed to confirm the deficiency
Clinical Significance
Alpha-1-antitrypsin deficiency is a genetic condition predisposing patients to early-onset emphysema and liver disease. It is significantly underdiagnosed, with many patients coded only for COPD without recognition of the underlying genetic cause. Capturing this code ensures appropriate augmentation therapy consideration and genetic counseling.
Documentation Requirements
- ✓Confirmed alpha-1-antitrypsin deficiency diagnosis
- ✓Alpha-1-antitrypsin serum level (typically < 11 micromol/L)
- ✓Genotype/phenotype documented (ZZ, SZ, MZ, etc.)
- ✓Associated conditions documented (emphysema, liver disease, panniculitis)
- ✓Current treatment (augmentation therapy with IV alpha-1 proteinase inhibitor)
- ✓Pulmonary function testing and liver function assessment