ICD-10-CM Alphabetic Index · FY 2027 141 Entries
Encephalitis in the ICD-10-CM Index ICD-10-CM
The main term Encephalitis (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute) carries 141 index entries pointing to 64 ICD-10-CM codes. The default entry is G04.90, the code the bare main term maps to; every indented line below refines the term by site, cause, or type. Verify any candidate code in the Tabular List before using it.
✓ Built from the official CMS FY 2027 index fileEffective Oct 1, 2026 – Sep 30, 2027
141
Index Entries
64
Codes Referenced
G04.90
Default Code
E
Letter
141 of 141 shown
ICD-10-CM
Index Entries Under Encephalitis 141 entries · 64 codes
Encephalitis (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute) G04.90
acute A86 see also Encephalitis, viral
disseminated G04.00
infectious G04.01
noninfectious G04.81
postimmunization (postvaccination) G04.02
postinfectious G04.01
inclusion body A85.8
necrotizing hemorrhagic G04.30
postimmunization G04.32
postinfectious G04.31
specified NEC G04.39
arboviral, arbovirus NEC A85.2
arthropod-borne NEC (viral) A85.2
Australian A83.4
California (virus) A83.5
Central European (tick-borne) A84.1
Czechoslovakian A84.1
Dawson's (inclusion body) A81.1
diffuse sclerosing A81.1
disseminated, acute G04.00
due to
cat scratch disease A28.1
malaria see Malaria
rickettsiosis see Rickettsiosis
smallpox inoculation G04.02
typhus see Typhus
Eastern equine A83.2
endemic (viral) A86
epidemic NEC (viral) A86
equine (acute) (infectious) (viral) A83.9
Eastern A83.2
Venezuelan A92.2
Western A83.1
Far Eastern (tick-borne) A84.0
following vaccination or other immunization procedure G04.02
herpes zoster B02.0
herpesviral B00.4
due to herpesvirus 6 B10.01
due to herpesvirus 7 B10.09
specified NEC B10.09
Ilheus (virus) A83.8
inclusion body A81.1
in (due to)
actinomycosis A42.82
adenovirus A85.1
Chagas' disease (chronic) B57.42
cytomegalovirus B25.8
enterovirus A85.0
herpes (simplex) virus B00.4
due to herpesvirus 6 B10.01
due to herpesvirus 7 B10.09
specified NEC B10.09
influenza see Influenza, with, encephalopathy
listeriosis A32.12
measles B05.0
mumps B26.2
naegleriasis B60.2
rubella B06.01
syphilis
congenital A50.42
late A52.14
toxoplasmosis (acquired) B58.2
congenital P37.1
tuberculosis A17.82
zoster B02.0
infectious (acute) (virus) NEC A86
Japanese (B type) A83.0
La Crosse A83.5
lead see Poisoning, lead
lethargica (acute) (infectious) A85.8
louping ill A84.89
lymphatica A87.2
Mengo A85.8
meningococcal A39.81
Murray Valley A83.4
parasitic NOS B71.9
periaxial G37.0
periaxialis (concentrica) (diffuse) G37.5
postchickenpox B01.11
postexanthematous NEC B09
postimmunization G04.02
postinfectious NEC G04.01
postmeasles B05.0
postvaccinal G04.02
postvaricella B01.11
postviral NEC A86
Powassan A84.81
Rasmussen G04.81
Rio Bravo A85.8
Russian
autumnal A83.0
spring-summer (taiga) A84.0
saturnine see Poisoning, lead
specified NEC G04.81
St. Louis A83.3
subacute sclerosing A81.1
summer A83.0
suppurative G04.81
tick-borne A84.9
Torula, torular (cryptococcal) B45.1
toxic NEC G92.8
type
B A83.0
C A83.3
van Bogaert's A81.1
Venezuelan equine A92.2
Vienna A85.8
viral, virus A86
arthropod-borne NEC A85.2
mosquito-borne A83.9
Australian X disease A83.4
California virus A83.5
Eastern equine A83.2
Japanese (B type) A83.0
Murray Valley A83.4
specified NEC A83.8
St. Louis A83.3
type B A83.0
type C A83.3
Western equine A83.1
tick-borne A84.9
biundulant A84.1
central European A84.1
Czechoslovakian A84.1
diphasic meningoencephalitis A84.1
Far Eastern A84.0
Russian spring-summer (taiga) A84.0
specified NEC A84.89
specified type NEC A85.8
tick-borne, specified NEC A84.89
Western equine A83.1
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Related Index Terms
Source: Centers for Medicare & Medicaid Services, FY 2027 ICD-10-CM Index to Diseases and Injuries release files, effective October 1, 2026 through September 30, 2027.
