FY2027 ICD-10-CM reference
G05.4: Myelitis in diseases classified elsewhere
By the HCC Buddy Coding Team
The official ICD-10-CM descriptor is Myelitis in diseases classified elsewhere. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Billable code. Verified against the official FY2027 order file.
FY2027 Tabular instructions
Instructions below include applicable chapter, section and parent-code notes. Each note identifies where it appears in the official source.
Excludes2
certain conditions originating in the perinatal period (P04-P96)
Source: G00-G99 (chapter, inherited).
Excludes2
certain infectious and parasitic diseases (A00-B99)
Source: G00-G99 (chapter, inherited).
Excludes2
complications of pregnancy, childbirth and the puerperium (O00-O9A)
Source: G00-G99 (chapter, inherited).
Excludes2
congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
Source: G00-G99 (chapter, inherited).
Excludes2
endocrine, nutritional and metabolic diseases (E00-E88)
Source: G00-G99 (chapter, inherited).
Excludes2
injury, poisoning and certain other consequences of external causes (S00-T88)
Source: G00-G99 (chapter, inherited).
Excludes2
neoplasms (C00-D49)
Source: G00-G99 (chapter, inherited).
Excludes2
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Source: G00-G99 (chapter, inherited).
Code first
underlying disease, such as:
Source: G05 (category, inherited).
Code first
congenital toxoplasmosis encephalitis, myelitis and encephalomyelitis (P37.1)
Source: G05 (category, inherited).
Code first
cytomegaloviral encephalitis, myelitis and encephalomyelitis (B25.8)
Source: G05 (category, inherited).
Code first
encephalitis, myelitis and encephalomyelitis (in) systemic lupus erythematosus (M32.19)
Source: G05 (category, inherited).
Code first
eosinophilic meningoencephalitis (B83.2)
Source: G05 (category, inherited).
Code first
human immunodeficiency virus [HIV] disease (B20)
Source: G05 (category, inherited).
Code first
poliovirus (A80.-)
Source: G05 (category, inherited).
Code first
suppurative otitis media (H66.01-H66.4)
Source: G05 (category, inherited).
Code first
systemic lupus erythematosus (M32.19)
Source: G05 (category, inherited).
Code first
trichinellosis (B75)
Source: G05 (category, inherited).
Excludes1
adenoviral encephalitis, myelitis and encephalomyelitis (A85.1)
Source: G05 (category, inherited).
Excludes1
encephalitis, myelitis and encephalomyelitis (in) measles (B05.0)
Source: G05 (category, inherited).
Excludes1
enteroviral encephalitis, myelitis and encephalomyelitis (A85.0)
Source: G05 (category, inherited).
Excludes1
herpesviral [herpes simplex] encephalitis, myelitis and encephalomyelitis (B00.4)
Source: G05 (category, inherited).
Excludes1
listerial encephalitis, myelitis and encephalomyelitis (A32.12)
Source: G05 (category, inherited).
Excludes1
meningococcal encephalitis, myelitis and encephalomyelitis (A39.81)
Source: G05 (category, inherited).
Excludes1
mumps encephalitis, myelitis and encephalomyelitis (B26.2)
Source: G05 (category, inherited).
Excludes1
postchickenpox encephalitis, myelitis and encephalomyelitis (B01.1-)
Source: G05 (category, inherited).
Excludes1
rubella encephalitis, myelitis and encephalomyelitis (B06.01)
Source: G05 (category, inherited).
Excludes1
toxoplasmosis encephalitis, myelitis and encephalomyelitis (B58.2)
Source: G05 (category, inherited).
Excludes1
zoster encephalitis, myelitis and encephalomyelitis (B02.0)
Source: G05 (category, inherited).
Instructional note
Meningomyelitis in diseases classified elsewhere
Source: G05.4 (self, direct).
Compare the FY2027 additions, removals and billable-status changes
What does G05.4 mean in FY2027?
The official ICD-10-CM descriptor is Myelitis in diseases classified elsewhere. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Is G05.4 billable in FY2027?
The FY2027 order file marks G05.4 as billable. Check the complete Tabular instructions and documentation before assigning it.
Does G05.4 map to an HCC?
In the CMS 2027 Initial ICD-10-CM Mappings (payment year 2027, 2026 dates of service), G05.4 maps to CMS-HCC V28 HCC 182 (Spinal Cord Disorders/Injuries). For 2027 dates of service, CMS has not yet published the payment year 2028 mappings. ESRD, RxHCC, PACE and HHS-HCC mappings are still pending verification for FY2027.
Source: CMS FY2027 ICD-10-CM order file. Read the FY2027 Official Guidelines.
Review the FY2026 April edition