G61.0
BillableGuillain-Barre syndrome
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is G61.0 an HCC code?
Yes. G61.0 maps to Myasthenia Gravis/Myoneural Conditions and Guillain-Barre Syndrome 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 G61.0
For G61.0to 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 G61.0 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
G61.0 is the ICD-10-CM diagnosis code for guillain-barre syndrome. An acute autoimmune condition where the body's immune system attacks nerve cells, causing rapid muscle weakness and potentially paralysis that typically develops over days to weeks. G61.0 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering polyneuropathies and other disorders of the peripheral nervous system (g60-g65).
Under the older CMS-HCC V24 model, G61.0 maps to Myasthenia Gravis/Myoneural Conditions and Guillain-Barre Syndrome (HCC 75) with a community, non-dual, aged base RAF weight of 0.425. 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.
This is an acute condition; ensure documentation supports the diagnosis with clinical presentation and diagnostic findings. Because G61.0 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 G61.0 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This is an acute condition; ensure documentation supports the diagnosis with clinical presentation and diagnostic findings
- •Consider sequencing this as a principal diagnosis if it is the primary reason for admission
Clinical Significance
Guillain-Barre syndrome is a rapidly progressive autoimmune polyneuropathy that can lead to respiratory failure and death if untreated. It is critical for risk adjustment because it reflects high-acuity neurological disease requiring intensive monitoring, immunotherapy, and often prolonged rehabilitation. Accurate capture ensures appropriate resource allocation for these complex patients.
Documentation Requirements
- ✓Clinical presentation: acute ascending weakness, areflexia, sensory changes
- ✓Diagnostic confirmation: nerve conduction studies/electromyography findings, cerebrospinal fluid analysis showing albuminocytologic dissociation
- ✓Temporal course: onset over days to weeks with progressive pattern
- ✓Treatment plan: intravenous immunoglobulin or plasmapheresis
- ✓Functional status: respiratory function monitoring, degree of paralysis
- ✓Provider's explicit diagnosis of Guillain-Barre syndrome
Commonly Confused Codes
- •G61.81 — Chronic inflammatory demyelinating polyneuritis (CIDP) is the chronic form lasting >8 weeks; Guillain-Barre syndrome is acute
- •G61.89 — Other inflammatory polyneuropathies is a catch-all for inflammatory neuropathies that do not meet Guillain-Barre syndrome criteria
- •G65.0 — Sequelae of Guillain-Barre syndrome is for residual effects after the acute phase has resolved, not the active disease
- •G62.81 — Critical illness polyneuropathy develops in ICU patients from sepsis/critical illness, not autoimmune etiology