ICD-10 · PDGM grouping
G04 Encephalitis, myelitis and encephalomyelitis
All 14 codes in the G04 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
14
Can lead a claim
14
Cannot lead a claim
0
What CMS assigns to G04
All 14 codes group to Neuro Rehabilitation (13) and MMTA - Other (1). 1 of the 14 counts toward the Paraplegia, Hemiplegia and Quadriplegia comorbidity subgroup; 13 are assigned none. Every code can lead a claim.
- Paraplegia, Hemiplegia and Quadriplegia: can award the low comorbidity tier as a secondary diagnosis.
Every code in G04
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| G04.0 Acute disseminated encephalitis and encephalomyelitis (ADEM) | ||||
| G04.00 | Acute disseminated encephalitis and encephalomyelitis, unspecifiedCMS: Acute disseminated encephalitis and encephalomyelitis, unsp | Can lead a claim | B | None |
| G04.01 | Postinfectious acute disseminated encephalitis and encephalomyelitis (postinfectious ADEM)CMS: Postinfect acute dissem encephalitis and encephalomyelitis | Can lead a claim | B | None |
| G04.02 | Postimmunization acute disseminated encephalitis, myelitis and encephalomyelitisCMS: Postimmun ac dissem encphlts, myelitis and encephalomyelitis | Can lead a claim | B | None |
| G04.1 | Tropical spastic paraplegia | Can lead a claim | B | Paraplegia, Hemiplegia and Quadriplegia |
| G04.2 | Bacterial meningoencephalitis and meningomyelitis, not elsewhere classifiedCMS: Bacterial meningoencephalitis and meningomyelitis, NEC | Can lead a claim | B | None |
| G04.3 Acute necrotizing hemorrhagic encephalopathy | ||||
| G04.30 | Acute necrotizing hemorrhagic encephalopathy, unspecified | Can lead a claim | B | None |
| G04.31 | Postinfectious acute necrotizing hemorrhagic encephalopathy | Can lead a claim | B | None |
| G04.32 | Postimmunization acute necrotizing hemorrhagic encephalopathyCMS: Postimmun acute necrotizing hemorrhagic encephalopathy | Can lead a claim | A | None |
| G04.39 | Other acute necrotizing hemorrhagic encephalopathy | Can lead a claim | B | None |
| G04.8 Other encephalitis, myelitis and encephalomyelitis | ||||
| G04.81 | Other encephalitis and encephalomyelitis | Can lead a claim | B | None |
| G04.82 | Acute flaccid myelitis | Can lead a claim | B | None |
| G04.89 | Other myelitis | Can lead a claim | B | None |
| G04.9 Encephalitis, myelitis and encephalomyelitis, unspecified | ||||
| G04.90 | Encephalitis and encephalomyelitis, unspecified | Can lead a claim | B | None |
| G04.91 | Myelitis, unspecified | Can lead a claim | B | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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