ICD10
ICD-10 Code G04.8: Other encephalitis, myelitis and encephalomyelitis
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Diseases of the nervous system (G00-G99).
When is it used?
- May be used when a clinician documents other encephalitis, myelitis and encephalomyelitis in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
- This entry may represent a broader category rather than the most specific billable code.
Code hierarchy
chapter
6Diseases of the nervous system (G00-G99)
block
G00-G09Inflammatory diseases of the central nervous system
category
G04Encephalitis, myelitis and encephalomyelitis
currentG04
Official coding notes
Code also
- any associated seizure (G40.-, R56.9)
Where you may see this code
You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.
Related specialists
NeurologistGeneral Physician
Related codes
Sibling codes
G04.0Acute disseminated encephalitis and encephalomyelitis (ADEM)G04.1Tropical spastic paraplegiabillableG04.2Bacterial meningoencephalitis and meningomyelitis, not elsewhere classifiedbillableG04.3Acute necrotizing hemorrhagic encephalopathyG04.9Encephalitis, myelitis and encephalomyelitis, unspecified
Mapped diagnoses and classifications
SNOMED_CT 70884002high
Allergic encephalitis
Source: SNOMED International ICD-10 map
SNOMED_CT 50776006high
Allergic encephalomyelitis
Source: SNOMED International ICD-10 map
SNOMED_CT 230185008high
Amoebic encephalitis
Source: SNOMED International ICD-10 map
SNOMED_CT 1259089005high
Autoimmune acquired autonomic encephalomyelitis
Source: SNOMED International ICD-10 map
SNOMED_CT 1259086003high
Autoimmune cerebellar inflammation
Source: SNOMED International ICD-10 map
SNOMED_CT 1259087007high
Autoimmune encephalitis caused by N-methyl-D-aspartate receptor antibody
Source: SNOMED International ICD-10 map
Coding guidelines
Compatibility
Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.
Legacy codes
G04.8
Replacement codes
G04.81 — Other encephalitis and encephalomyelitisG04.82 — Acute flaccid myelitisG04.89 — Other myelitis
Common synonyms
Other encephalitis, myelitis and encephalomyelitis
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.