G37.0
BillableDiffuse sclerosis of central nervous system
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is G37.0 an HCC code?
Yes. G37.0 maps to Multiple Sclerosis under the CMS-HCC V28 risk adjustment model (and Multiple Sclerosis 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 G37.0
For G37.0 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 G37.0 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
G37.0 is the ICD-10-CM diagnosis code for diffuse sclerosis of central nervous system. A progressive disease affecting the brain and spinal cord where the protective coating of nerve fibers gradually deteriorates across widespread areas. G37.0 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering demyelinating diseases of the central nervous system (g35-g37).
Under the CMS-HCC V28 risk adjustment model, G37.0 maps to Multiple Sclerosis (HCC 198) with a community, non-dual, aged base RAF weight of 0.000. Under the older V24 model, G37.0 mapped to the same category but with a base RAF weight of 0.476 — V28 recalibrated weights across the entire model. 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.
Distinguish from multiple sclerosis by confirming diffuse rather than focal demyelination pattern. Because G37.0 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 G37.0 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Distinguish from multiple sclerosis by confirming diffuse rather than focal demyelination pattern
- •Document imaging findings showing widespread CNS involvement
Clinical Significance
Diffuse sclerosis of the central nervous system represents a progressive demyelinating condition affecting widespread areas of the brain and spinal cord. Unlike multiple sclerosis which typically has focal plaques, diffuse sclerosis involves large confluent areas of demyelination. Accurate identification differentiates this from other demyelinating conditions and ensures appropriate risk adjustment.
Documentation Requirements
- ✓Documentation specifically identifying diffuse sclerosis of the CNS (also known as Schilder disease)
- ✓Neuroimaging (MRI) showing large, symmetric, bilateral areas of white matter demyelination
- ✓Distinction from multiple sclerosis documented (diffuse vs. focal pattern)
- ✓Neurological examination findings documenting progressive deficits
- ✓Biopsy results if available confirming the pathological pattern
- ✓Current treatment plan and specialist involvement
Excludes 1 — Do NOT code together
- X linked adrenoleukodystrophy (E71.52-)
Commonly Confused Codes
- •G35 — Multiple sclerosis; has focal plaques rather than diffuse demyelination pattern
- •G37.5 — Concentric sclerosis (Balo); has characteristic concentric ring pattern on imaging
- •G37.9 — Demyelinating disease of CNS, unspecified; too nonspecific when diffuse sclerosis is documented
- •G31.80 — Leukodystrophy, unspecified; inherited white matter disease vs. acquired diffuse sclerosis
- •G36.9 — Acute disseminated demyelination; acute presentation rather than progressive diffuse pattern