Encephalitis, myelitis and encephalomyelitis in diseases classified elsewhere (G05) ICD-10-CM
The G05 code range covers encephalitis, myelitis and encephalomyelitis in diseases classified elsewhere with 3 ICD-10-CM diagnosis codes. 2 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Code First
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
- underlying disease, such as:
- congenital toxoplasmosis encephalitis, myelitis and encephalomyelitis P37.1
- cytomegaloviral encephalitis, myelitis and encephalomyelitis B25.8
- encephalitis, myelitis and encephalomyelitis in systemic lupus erythematosus M32.19
- eosinophilic meningoencephalitis B83.2
- human immunodeficiency virus [HIV] disease B20
- poliovirus A80
- suppurative otitis media H66.01 H66.4
- systemic lupus erythematosus M32.19
- trichinellosis B75
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- adenoviral encephalitis, myelitis and encephalomyelitis A85.1
- encephalitis, myelitis and encephalomyelitis in measles B05.0
- enteroviral encephalitis, myelitis and encephalomyelitis A85.0
- herpesviral [herpes simplex] encephalitis, myelitis and encephalomyelitis B00.4
- listerial encephalitis, myelitis and encephalomyelitis A32.12
- meningococcal encephalitis, myelitis and encephalomyelitis A39.81
- mumps encephalitis, myelitis and encephalomyelitis B26.2
- postchickenpox encephalitis, myelitis and encephalomyelitis B01.1
- rubella encephalitis, myelitis and encephalomyelitis B06.01
- toxoplasmosis encephalitis, myelitis and encephalomyelitis B58.2
- zoster encephalitis, myelitis and encephalomyelitis B02.0
Codes in the G05 Range 3 codes · 2 billable
About the G05 Code Range
These conditions involve inflammation of the brain, spinal cord, or both in diseases classified elsewhere.
Within G05, G05.3 covers inflammation of the brain or of both the brain and spinal cord. G05.4 covers inflammation of the spinal cord.
Questions About This Page
How many billable codes are in the G05 range?
Of the 3 codes in this range, 2 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the G05 range classify?
The range classifies encephalitis, myelitis and encephalomyelitis in diseases classified elsewhere. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
