E76.219
BillableMorquio mucopolysaccharidoses, unspecified
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is E76.219 an HCC code?
Yes. E76.219 maps to Lysosomal Storage 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 E76.219
For E76.219 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 E76.219 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
E76.219 is the ICD-10-CM diagnosis code for morquio mucopolysaccharidoses, unspecified. Morquio mucopolysaccharidosis, unspecified type, is a rare inherited metabolic disorder causing skeletal deformities and progressive physical problems when the specific type (A or B) is not documented. E76.219 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, E76.219 maps to Lysosomal Storage Disorders (HCC 49) with a community, non-dual, aged base RAF weight of 0.226. Under the older CMS-HCC V24 model, E76.219 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.
Use this code only when the specific Morquio type (A or B) cannot be determined from the medical record. Because E76.219 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 E76.219 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 Morquio type (A or B) cannot be determined from the medical record
- •Query the provider to determine the specific type if possible, as this affects treatment options and genetic counseling
Clinical Significance
Morquio mucopolysaccharidoses, unspecified is used when MPS IV is diagnosed but the subtype (A vs. B) has not been determined or documented. This code indicates a need for further diagnostic workup since treatment options differ between subtypes, particularly with elosulfase alfa being specific to Morquio A.
Documentation Requirements
- ✓Provider diagnosis of Morquio syndrome or MPS IV without specification of A or B subtype
- ✓Clinical findings consistent with MPS IV: skeletal dysplasia, short trunk dwarfism, joint laxity, corneal clouding
- ✓Reason subtype is not specified (testing pending, unavailable, or not yet ordered)
- ✓Current symptom management and care plan
- ✓Referral for enzyme assay or genetic testing if not yet performed